Fossil

#!/usr/bin/make
#
#### The toplevel directory of the source tree.  Fossil can be built
#    in a directory that is separate from the source tree.  Just change
#    the following to point from the build directory to the src/ folder.
#
SRCDIR = ./src

#### The directory into which object code files should be written.
#
#
OBJDIR = ./bld
OBJDIR = ./obj

#### C Compiler and options for use in building executables that
#    will run on the platform that is doing the build.  This is used
#    to compile code-generator programs as part of the build process.
#    See TCC below for the C compiler for building the finished binary.
#
BCC = gcc -g -O2

   || strcmp(zPath, "_FOSSIL_-journal")==0
   || strcmp(zPath, "_FOSSIL_-wal")==0
   || strcmp(zPath, "_FOSSIL_-shm")==0
   || strcmp(zPath, ".fos")==0
   || strcmp(zPath, ".fos-journal")==0
   || strcmp(zPath, ".fos-wal")==0
   || strcmp(zPath, ".fos-shm")==0
   || (pOmit && blob_compare(&pathname, pOmit)==0)
   || blob_compare(&pathname, pOmit)==0
  ){
    fossil_warning("cannot add %s", zPath);
  }else{
    if( !file_is_simple_pathname(zPath) ){
      fossil_fatal("filename contains illegal characters: %s", zPath);
    }
#if defined(_WIN32)

      blob_reset(&pathname);
    }
    free(zName);
  }
  db_multi_exec("DELETE FROM vfile WHERE deleted AND rid=0");
  db_end_transaction(0);
}

/*
** COMMAND: addremove
**
** Usage: %fossil addremove ?--dotfiles? ?--ignore GLOBPATTERN? ?--test?
**
** Do all necessary "add" and "rm" commands to synchronize the repository
** with the content of the working checkout
**
**  *  All files in the checkout but not in the repository (that is,
**     all files displayed using the "extra" command) are added as
**     if by the "add" command.
**
**  *  All files in the repository but missing from the checkout (that is,
**     all files that show as MISSING with the "status" command) are
**     removed as if by the "rm" command.
**
** The command does not "commit".  You must run the "commit" separately
** as a separate step.
**
** Files and directories whose names begin with "." are ignored unless
** the --dotfiles option is used.
**
** The --ignore option overrides the "ignore-glob" setting.  See
** documentation on the "setting" command for further information.
**
** The --test option shows what would happen without actually doing anything.
**
** This command can be used to track third party software.
*/
void import_cmd(void){
  Blob path;
  const char *zIgnoreFlag = find_option("ignore",0,1);
  int allFlag = find_option("dotfiles",0,0)!=0;
  int isTest = find_option("test",0,0)!=0;
  int n;
  Stmt q;
  int vid;
  Blob repo;
  int nAdd = 0;
  int nDelete = 0;

  if( zIgnoreFlag==0 ){
    zIgnoreFlag = db_get("ignore-glob", 0);
  }
  db_must_be_within_tree();
  vid = db_lget_int("checkout",0);
  if( vid==0 ){
    fossil_panic("no checkout to add to");
  }
  db_begin_transaction();
  db_multi_exec("CREATE TEMP TABLE sfile(x TEXT PRIMARY KEY)");
  n = strlen(g.zLocalRoot);
  blob_init(&path, g.zLocalRoot, n-1);
  /* now we read the complete file structure into a temp table */
  vfile_scan(0, &path, blob_size(&path), allFlag);
  if( file_tree_name(g.zRepositoryName, &repo, 0) ){
    db_multi_exec("DELETE FROM sfile WHERE x=%B", &repo);
  }

  /* step 1: search for extra files */
  db_prepare(&q, 
      "SELECT x, %Q || x FROM sfile"
      " WHERE x NOT IN ('manifest','manifest.uuid','_FOSSIL_',"
                       "'_FOSSIL_-journal','.fos','.fos-journal',"
                       "'_FOSSIL_-wal','_FOSSIL_-shm','.fos-wal',"
                       "'.fos-shm')"
      "   AND NOT %s"
      " ORDER BY 1",
      g.zLocalRoot,
      glob_expr("x", zIgnoreFlag)
  );
  while( db_step(&q)==SQLITE_ROW ){
    add_one_file(db_column_text(&q, 1), vid, 0);
    nAdd++;
  }
  db_finalize(&q);
  /* step 2: search for missing files */
  db_prepare(&q, 
      "SELECT pathname,%Q || pathname,deleted FROM vfile"
      " WHERE deleted!=1"
      " ORDER BY 1",
      g.zLocalRoot
  );
  while( db_step(&q)==SQLITE_ROW ){
    const char * zFile;
    const char * zPath;

    zFile = db_column_text(&q, 0);
    zPath = db_column_text(&q, 1);
    if( !file_isfile(zPath) ){
      if( !isTest ){
        db_multi_exec("UPDATE vfile SET deleted=1 WHERE pathname=%Q", zFile);
      }
      printf("DELETED  %s\n", zFile);
      nDelete++;
    }
  }
  db_finalize(&q);
  /* show cmmand summary */
  printf("added %d files, deleted %d files\n", nAdd, nDelete);

  db_end_transaction(isTest);
}


/*
** Rename a single file.
**
** The original name of the file is zOrig.  The new filename is zNew.
*/
static void mv_one_file(int vid, const char *zOrig, const char *zNew){

** that can be useful before or after a period of disconnected operation.
**
** On Win32 systems, the file is named "_fossil" and is located in
** %LOCALAPPDATA%, %APPDATA% or %HOMEPATH%.
**
** Available operations are:
**
**    ignore     Arguments are repositories that should be ignored
**               by subsequent list, pull, push, rebuild, and sync.
**
**    list | ls  Display the location of all repositories
**
**    pull       Run a "pull" operation on all repositories
**
**    push       Run a "push" on all repositories
**
**    rebuild    Rebuild on all repositories
**
**    sync       Run a "sync" on all repositories
**
** Respositories are automatically added to the set of known repositories
** when one of the following commands against the repository: clone, info,
** pull, push, or sync.  Even previously ignored repositories are added back
** pull, push, or sync
** to the list of repositories by these commands.
*/
void all_cmd(void){
  int n;
  Stmt q;
  const char *zCmd;
  char *zSyscmd;
  char *zFossil;

    zCmd = "push -autourl -R";
  }else if( strncmp(zCmd, "pull", n)==0 ){
    zCmd = "pull -autourl -R";
  }else if( strncmp(zCmd, "rebuild", n)==0 ){
    zCmd = "rebuild";
  }else if( strncmp(zCmd, "sync", n)==0 ){
    zCmd = "sync -autourl -R";
  }else if( strncmp(zCmd, "ignore", n)==0 ){
    int j;
    db_begin_transaction();
    for(j=3; j<g.argc; j++){
      db_multi_exec("DELETE FROM global_config WHERE name GLOB 'repo:%q'",
         g.argv[j]);
    }
    db_end_transaction(0);
    return;
  }else{
    fossil_fatal("\"all\" subcommand should be one of: "
                 "ignore list ls push pull rebuild sync");
                 "list ls push pull rebuild sync");
  }
  zFossil = quoteFilename(fossil_nameofexe());
  zFossil = quoteFilename(g.argv[0]);
  nMissing = 0;
  db_prepare(&q,
     "SELECT DISTINCT substr(name, 6) COLLATE nocase"
     "  FROM global_config"
     " WHERE substr(name, 1, 5)=='repo:' ORDER BY 1"
  );
  while( db_step(&q)==SQLITE_ROW ){

      printf("%s\n", zFilename);
      continue;
    }
    zQFilename = quoteFilename(zFilename);
    zSyscmd = mprintf("%s %s %s", zFossil, zCmd, zQFilename);
    printf("%s\n", zSyscmd);
    fflush(stdout);
    fossil_system(zSyscmd);
    portable_system(zSyscmd);
    free(zSyscmd);
    free(zQFilename);
  }
  
  /* If any repositories whose names appear in the ~/.fossil file could not
  ** be found, remove those names from the ~/.fossil file.
  */

  if( g.argc==3 ){
    printf(
      "\n"
      "Note: the local check-out has not been updated to the new\n"
      "      branch.  To begin working on the new branch, do this:\n"
      "\n"
      "      %s update %s\n",
      fossil_nameofexe(), zBranch
      g.argv[0], zBranch
    );
  }


  /* Commit */
  db_end_transaction(0);
  

**    %fossil branch list
**
**        List all branches
**
*/
void branch_cmd(void){
  int n;
  const char *zCmd = "list";
  db_find_and_open_repository(1);
  if( g.argc<2 ){
  if( g.argc<3 ){
    usage("new|list ...");
  }
  if( g.argc>=3 ) zCmd = g.argv[2];
  n = strlen(zCmd);
  if( strncmp(zCmd,"new",n)==0 ){
  n = strlen(g.argv[2]);
  if( n>=2 && strncmp(g.argv[2],"new",n)==0 ){
    branch_new();
  }else if( strncmp(zCmd,"list",n)==0 ){
  }else if( n>=2 && strncmp(g.argv[2],"list",n)==0 ){
    Stmt q;
    int vid;
    char *zCurrent = 0;

    if( g.localOpen ){
      vid = db_lget_int("checkout", 0);
      zCurrent = db_text(0, "SELECT value FROM tagxref"
                            " WHERE rid=%d AND tagid=%d", vid, TAG_BRANCH);
    }
    compute_leaves(0, 1);
    db_prepare(&q,
      "%s"
      "SELECT DISTINCT value FROM tagxref"
      " WHERE tagid=%d AND value NOT NULL AND rid IN leaves"
      " ORDER BY value /*sort*/",
      TAG_BRANCH
      "   AND blob.rid IN (SELECT rid FROM tagxref"
      "                     WHERE tagid=%d AND tagtype==2 AND srcid!=0)"
      " ORDER BY event.mtime DESC",
      timeline_query_for_tty(), TAG_BRANCH
    );
    while( db_step(&q)==SQLITE_ROW ){
      const char *zBr = db_column_text(&q, 0);
    print_timeline(&q, 2000);
      int isCur = zCurrent!=0 && strcmp(zCurrent,zBr)==0;
      printf("%s%s\n", (isCur ? "* " : "  "), zBr);
    }
    db_finalize(&q);
  }else{
    fossil_panic("branch subcommand should be one of: "
                 "new list");
  }
}

  db_must_be_within_tree();
       /* 012345678901234 */
  printf("repository:   %s\n", db_lget("repository",""));
  printf("local-root:   %s\n", g.zLocalRoot);
  printf("server-code:  %s\n", db_get("server-code", ""));
  vid = db_lget_int("checkout", 0);
  if( vid ){
    show_common_info(vid, "checkout:", 1, 1);
    show_common_info(vid, "checkout:", 0);
  }
  changes_cmd();
}

/*
** COMMAND: ls
**

                   g.zLocalRoot);
#if defined(_WIN32)
  blob_add_cr(&text);
#endif
  blob_write_to_file(&text, zFile);
  zCmd = mprintf("%s \"%s\"", zEditor, zFile);
  printf("%s\n", zCmd);
  if( fossil_system(zCmd) ){
  if( portable_system(zCmd) ){
    fossil_panic("editor aborted");
  }
  blob_reset(&text);
  blob_read_from_file(&text, zFile);
  blob_remove_cr(&text);
  unlink(zFile);
  free(zFile);

** COMMAND: ci
** COMMAND: commit
**
** Usage: %fossil commit ?OPTIONS? ?FILE...?
**
** Create a new version containing all of the changes in the current
** checkout.  You will be prompted to enter a check-in comment unless
** the comment has been specified on the command-line using "-m" or a 
** the comment has been specified on the command-line using "-m".
** file containing the comment using -M.  The editor defined in the
** "editor" fossil option (see %fossil help set) will be used, or from
** the "VISUAL" or "EDITOR" environment variables (in that order) if
** no editor is set.
** The editor defined in the "editor" fossil option (see %fossil help set)
** will be used, or from the "VISUAL" or "EDITOR" environment variables
** (in that order) if no editor is set.
**
** You will be prompted for your GPG passphrase in order to sign the
** new manifest unless the "--nosign" option is used.  All files that
** All files that have changed will be committed unless some subset of
** files is specified on the command line.
** have changed will be committed unless some subset of files is
** specified on the command line.
**
** The --branch option followed by a branch name causes the new check-in
** The --branch option followed by a branch name cases the new check-in
** to be placed in the named branch.  The --bgcolor option can be followed
** by a color name (ex:  '#ffc0c0') to specify the background color of
** entries in the new branch when shown in the web timeline interface.
**
** A check-in is not permitted to fork unless the --force or -f
** option appears.  A check-in is not allowed against a closed check-in.
**
** The --private option creates a private check-in that is never synced.
** Children of private check-ins are automatically private.
**
** Options:
**
**    --comment|-m COMMENT-TEXT
**    --message-file|-M COMMENT-FILE
**    --branch NEW-BRANCH-NAME
**    --bgcolor COLOR
**    --nosign
**    --force|-f
**    --private
**    --baseline
**    --delta

    g.markPrivate = 1;
  }

  /*
  ** Autosync if autosync is enabled and this is not a private check-in.
  */
  if( !g.markPrivate ){
    if( autosync(AUTOSYNC_PULL) ){
    autosync(AUTOSYNC_PULL);
      Blob ans;
      blob_zero(&ans);
      prompt_user("continue in spite of sync failure (y/N)? ", &ans);
      if( blob_str(&ans)[0]!='y' ){
        fossil_exit(1);
      }
    }
  }

  /* Require confirmation to continue with the check-in if there is
  ** clock skew
  */
  if( g.clockSkewSeen ){
    Blob ans;

  if( useCksum ){
    /* Verify that the repository checksum matches the expected checksum
    ** calculated before the checkin started (and stored as the R record
    ** of the manifest file).
    */
    vfile_aggregate_checksum_repository(nvid, &cksum2);
    if( blob_compare(&cksum1, &cksum2) ){
      vfile_compare_repository_to_disk(nvid);
      fossil_panic("tree checksum does not match repository after commit");
    }
  
    /* Verify that the manifest checksum matches the expected checksum */
    vfile_aggregate_checksum_manifest(nvid, &cksum2, &cksum1b);
    if( blob_compare(&cksum1, &cksum1b) ){
      fossil_panic("manifest checksum does not agree with manifest: "

    return 0;
  }
  zRand = db_text(0, "SELECT hex(randomblob(10))");
  zOut = mprintf("out-%s", zRand);
  zIn = mprintf("in-%z", zRand);
  blob_write_to_file(pIn, zOut);
  zCmd = mprintf("%s %s %s", zBase, zIn, zOut);
  rc = fossil_system(zCmd);
  rc = portable_system(zCmd);
  free(zCmd);
  if( rc==0 ){
    if( pOut==pIn ){
      blob_reset(pIn);
    }
    blob_zero(pOut);
    blob_read_from_file(pOut, zIn);

      }else if( strcmp(zName,"@reportfmt")==0 ){
        db_multi_exec("DELETE FROM reportfmt");
      }
    }
    db_end_transaction(0);
    printf("Configuration reset to factory defaults.\n");
    printf("To recover, use:  %s %s import %s\n", 
            fossil_nameofexe(), g.argv[1], zBackup);
            g.argv[0], g.argv[1], zBackup);
  }else
  {
    fossil_fatal("METHOD should be one of:"
                 " export import merge pull push reset");
  }
}

  }
  if( g.cgiOutput ){
    g.cgiOutput = 0;
    cgi_printf("<h1>Database Error</h1>\n"
               "<pre>%h</pre><p>%s</p>", z, zRebuildMsg);
    cgi_reply();
  }else{
    fprintf(stderr, "%s: %s\n\n%s", fossil_nameofexe(), z, zRebuildMsg);
    fprintf(stderr, "%s: %s\n\n%s", g.argv[0], z, zRebuildMsg);
  }
  db_force_rollback();
  fossil_exit(1);
}

static int nBegin = 0;      /* Nesting depth of BEGIN */
static int isNewRepo = 0;   /* True if the repository is newly created */

  if( useAttach ){
    db_open_or_attach(zDbName, "configdb");
    g.dbConfig = 0;
  }else{
    g.dbConfig = openDatabase(zDbName);
  }
  g.configOpen = 1;
  free(zDbName);
}

/*
** If zDbName is a valid local database file, open it and return
** true.  If it is not a valid local database file, return 0.
*/
static int isValidLocalDb(const char *zDbName){

    rid = content_put(&manifest, 0, 0);
    manifest_crosslink(rid, &manifest);
  }
}

/*
** COMMAND: new
** COMMAND: init
**
** Usage: %fossil new ?OPTIONS? FILENAME
**    Or: %fossil init ?OPTIONS? FILENAME
**
** Create a repository for a new project in the file named FILENAME.
** This command is distinct from "clone".  The "clone" command makes
** a copy of an existing project.  This command starts a new project.
**
** By default, your current login name is used to create the default
** admin user. This can be overridden using the -A|--admin-user

  { "dont-push",     0,                0, "off"                 },
  { "editor",        0,               16, ""                    },
  { "gdiff-command", 0,               16, "gdiff"               },
  { "ignore-glob",   0,               40, ""                    },
  { "http-port",     0,               16, "8080"                },
  { "localauth",     0,                0, "off"                 },
  { "manifest",      0,                0, "off"                 },
  { "mtime-changes", 0,                0, "on"                  },
  { "mtime-changes", 0,                0, "off"                 },
  { "pgp-command",   0,               32, "gpg --clearsign -o " },
  { "proxy",         0,               32, "off"                 },
  { "repo-cksum",    0,                0, "on"                  },
  { "ssh-command",   0,               32, ""                    },
  { "web-browser",   0,               32, ""                    },
  { 0,0,0,0 }
};

**
** Given two input files, create and output a delta that carries
** the first file into the second.
*/
void delta_create_cmd(void){
  Blob orig, target, delta;
  if( g.argc!=5 ){
    usage("ORIGIN TARGET DELTA");
    fprintf(stderr,"Usage: %s %s ORIGIN TARGET DELTA\n", g.argv[0], g.argv[1]);
    fossil_exit(1);
  }
  if( blob_read_from_file(&orig, g.argv[2])<0 ){
    fprintf(stderr,"cannot read %s\n", g.argv[2]);
    fossil_exit(1);
  }
  if( blob_read_from_file(&target, g.argv[3])<0 ){
    fprintf(stderr,"cannot read %s\n", g.argv[3]);

**
** Given an input files and a delta, apply the delta to the input file
** and write the result.
*/
void delta_apply_cmd(void){
  Blob orig, target, delta;
  if( g.argc!=5 ){
    usage("ORIGIN DELTA TARGET");
    fprintf(stderr,"Usage: %s %s ORIGIN DELTA TARGET\n", g.argv[0], g.argv[1]);
    fossil_exit(1);
  }
  if( blob_read_from_file(&orig, g.argv[2])<0 ){
    fprintf(stderr,"cannot read %s\n", g.argv[2]);
    fossil_exit(1);
  }
  if( blob_read_from_file(&delta, g.argv[3])<0 ){
    fprintf(stderr,"cannot read %s\n", g.argv[3]);

#include <assert.h>

/*
** Diff option flags
*/
#define DIFF_NEWFILE  0x01    /* Treat non-existing fails as empty files */
#define DIFF_NOEOLWS  0x02    /* Ignore whitespace at the end of lines */

/*
** This function implements a cross-platform "system()" interface.
*/
int portable_system(const char *zOrigCmd){
  int rc;
#if defined(_WIN32)
  /* On windows, we have to put double-quotes around the entire command.
  ** Who knows why - this is just the way windows works.
  */
  char *zNewCmd = mprintf("\"%s\"", zOrigCmd);
  rc = system(zNewCmd);
  free(zNewCmd);
#else
  /* On unix, evaluate the command directly.
  */
  rc = system(zOrigCmd);
#endif 
  return rc; 
}

/*
** Show the difference between two files, one in memory and one on disk.
**
** The difference is the set of edits needed to transform pFile1 into
** zFile2.  The content of pFile1 is in memory.  zFile2 exists on disk.
**

    blob_zero(&cmd);
    blob_appendf(&cmd, "%s ", zDiffCmd);
    shell_escape(&cmd, blob_str(&nameFile1));
    blob_append(&cmd, " ", 1);
    shell_escape(&cmd, zFile2);

    /* Run the external diff command */
    fossil_system(blob_str(&cmd));
    portable_system(blob_str(&cmd));

    /* Delete the temporary file and clean up memory used */
    unlink(blob_str(&nameFile1));
    blob_reset(&nameFile1);
    blob_reset(&cmd);
  }
}

    blob_zero(&cmd);
    blob_appendf(&cmd, "%s ", zDiffCmd);
    shell_escape(&cmd, zTemp1);
    blob_append(&cmd, " ", 1);
    shell_escape(&cmd, zTemp2);

    /* Run the external diff command */
    fossil_system(blob_str(&cmd));
    portable_system(blob_str(&cmd));

    /* Delete the temporary file and clean up memory used */
    unlink(zTemp1);
    unlink(zTemp2);
    blob_reset(&cmd);
  }
}

** no "--to" option then the (possibly edited) files in the current check-out
** are used.
**
** The "-i" command-line option forces the use of the internal diff logic
** rather than any external diff program that might be configured using
** the "setting" command.  If no external diff program is configured, then
** the "-i" option is a no-op.  The "-i" option converts "gdiff" into "diff".
**
** The "-N" or "--new-file" option causes the complete text of added or
** deleted files to be displayed.
*/
void diff_cmd(void){
  int isGDiff;               /* True for gdiff.  False for normal diff */
  int isInternDiff;          /* True for internal diff */
  int hasNFlag;              /* True if -N or --new-file flag is used */
  const char *zFrom;         /* Source version number */
  const char *zTo;           /* Target version number */

    { "spl",        3, "application/x-futuresplash"        },
    { "src",        3, "application/x-wais-source"         },
    { "step",       4, "application/STEP"                  },
    { "stl",        3, "application/SLA"                   },
    { "stp",        3, "application/STEP"                  },
    { "sv4cpio",    7, "application/x-sv4cpio"             },
    { "sv4crc",     6, "application/x-sv4crc"              },
    { "svg",        3, "image/svg+xml"                     },
    { "swf",        3, "application/x-shockwave-flash"     },
    { "t",          1, "application/x-troff"               },
    { "tar",        3, "application/x-tar"                 },
    { "tcl",        3, "application/x-tcl"                 },
    { "tex",        3, "application/x-tex"                 },
    { "texi",       4, "application/x-texinfo"             },
    { "texinfo",    7, "application/x-texinfo"             },

/*
** Copyright (c) 2010 D. Richard Hipp
**
** This program is free software; you can redistribute it and/or
** modify it under the terms of the Simplified BSD License (also
** known as the "2-Clause License" or "FreeBSD License".)

** This program is distributed in the hope that it will be useful,
** but without any warranty; without even the implied warranty of
** merchantability or fitness for a particular purpose.
**
** Author contact information:
**   drh@sqlite.org
**
*******************************************************************************
**
** This file contains code used to export the content of a Fossil
** repository in the git-fast-import format.
*/
#include "config.h"
#include "export.h"
#include <assert.h>

/*
** Output a "committer" record for the given user.
*/
static void print_person(const char *zUser){
  static Stmt q;
  const char *zContact;
  char *zName;
  char *zEmail;
  int i, j;

  if( zUser==0 ){
    printf(" <unknown>");
    return;
  }
  db_static_prepare(&q, "SELECT info FROM user WHERE login=:user");
  db_bind_text(&q, ":user", zUser);
  if( db_step(&q)!=SQLITE_ROW ){
    db_reset(&q);
    for(i=0; zUser[i] && zUser[i]!='>' && zUser[i]!='<'; i++){}
    if( zUser[i]==0 ){
      printf(" <%s>", zUser);
      return;
    }
    zName = mprintf("%s", zUser);
    for(i=j=0; zName[i]; i++){
      if( zName[i]!='<' && zName[i]!='>' ){
        zName[j++] = zName[i];
      }
    }
    zName[j] = 0;
    printf(" %s <%s>", zName, zUser);
    free(zName);
    return;
  }
  zContact = db_column_text(&q, 0);
  for(i=0; zContact[i] && zContact[i]!='>' && zContact[i]!='<'; i++){}
  if( zContact[i]==0 ){
    printf(" %s <%s>", zContact, zUser);
    db_reset(&q);
    return;
  }
  if( zContact[i]=='<' ){
    zEmail = mprintf("%s", &zContact[i]);
    for(i=0; zEmail[i] && zEmail[i]!='>'; i++){}
    if( zEmail[i]=='>' ) zEmail[i+1] = 0;
  }else{
    zEmail = mprintf("<%s>", zUser);
  }
  zName = mprintf("%.*s", i, zContact);
  for(i=j=0; zName[i]; i++){
    if( zName[i]!='"' ) zName[j++] = zName[i];
  }
  zName[j] = 0;
  printf(" %s %s", zName, zEmail);
  free(zName);
  free(zEmail);
  db_reset(&q);
}


/*
** COMMAND: export
**
** Usage: %fossil export
**
** Write an export of all check-ins to standard output.  The export is
** written in the Git "fast-import" format.
**
** Run this command within a checkout.  Or use the -R or --repository
** option to specify a Fossil repository to be exported.
**
** Only check-ins are exported.  Git does not support tickets or wiki
** or events or attachments, so none of that is exported.
*/
void export_cmd(void){
  Stmt q;
  int i;
  Bag blobs, vers;
  bag_init(&blobs);
  bag_init(&vers);

  db_find_and_open_repository(1);

  /* Step 1:  Generate "blob" records for every artifact that is part
  ** of a check-in 
  */
  fossil_binary_mode(stdout);
  db_prepare(&q, "SELECT DISTINCT fid FROM mlink WHERE fid>0");
  while( db_step(&q)==SQLITE_ROW ){
    int rid = db_column_int(&q, 0);
    Blob content;
    content_get(rid, &content);
    printf("blob\nmark :%d\ndata %d\n", rid, blob_size(&content));
    bag_insert(&blobs, rid);
    fwrite(blob_buffer(&content), 1, blob_size(&content), stdout);
    printf("\n");
    blob_reset(&content);
  }
  db_finalize(&q);

  /* Output the commit records.
  */
  db_prepare(&q,
    "SELECT strftime('%%s',mtime), objid, coalesce(comment,ecomment),"
    "       coalesce(user,euser),"
    "       (SELECT value FROM tagxref WHERE rid=objid AND tagid=%d)"
    "  FROM event"
    " WHERE type='ci'"
    " ORDER BY mtime ASC",
    TAG_BRANCH
  );
  while( db_step(&q)==SQLITE_ROW ){
    sqlite3_int64 secondsSince1970 = db_column_int64(&q, 0);
    int ckinId = db_column_int(&q, 1);
    const char *zComment = db_column_text(&q, 2);
    const char *zUser = db_column_text(&q, 3);
    const char *zBranch = db_column_text(&q, 4);
    char *zBr;
    Manifest *p;
    ManifestFile *pFile;
    const char *zFromType;

    bag_insert(&vers, ckinId);
    if( zBranch==0 ) zBranch = "trunk";
    zBr = mprintf("%s", zBranch);
    for(i=0; zBr[i]; i++){
      if( !fossil_isalnum(zBr[i]) ) zBr[i] = '_';
    }
    printf("commit refs/heads/%s\nmark :%d\n", zBr, ckinId);
    free(zBr);
    printf("committer");
    print_person(zUser);
    printf(" %lld +0000\n", secondsSince1970);
    if( zComment==0 ) zComment = "null comment";
    printf("data %d\n%s\n", (int)strlen(zComment), zComment);
    p = manifest_get(ckinId, CFTYPE_ANY);
    zFromType = "from";
    for(i=0; i<p->nParent; i++){
      int pid = fast_uuid_to_rid(p->azParent[i]);
      if( pid==0 || !bag_find(&vers, pid) ) continue;
      printf("%s :%d\n", zFromType, fast_uuid_to_rid(p->azParent[i]));
      zFromType = "merge";
    }
    printf("deleteall\n");
    manifest_file_rewind(p);
    while( (pFile=manifest_file_next(p, 0))!=0 ){
      int fid = fast_uuid_to_rid(pFile->zUuid);
      const char *zPerm = "100644";
      if( fid==0 ) continue;
      if( pFile->zPerm && strstr(pFile->zPerm,"x") ) zPerm = "100755";
      if( !bag_find(&blobs, fid) ) continue;
      printf("M %s :%d %s\n", zPerm, fid, pFile->zName);
    }
    manifest_destroy(p);
    printf("\n");
  }
  db_finalize(&q);
  bag_clear(&blobs);


  /* Output tags */
  db_prepare(&q,
     "SELECT tagname, rid, strftime('%%s',mtime)"
     "  FROM tagxref JOIN tag USING(tagid)"
     " WHERE tagtype=1 AND tagname GLOB 'sym-*'"
  );
  while( db_step(&q)==SQLITE_ROW ){
    const char *zTagname = db_column_text(&q, 0);
    int rid = db_column_int(&q, 1);
    sqlite3_int64 secSince1970 = db_column_int64(&q, 2);
    if( rid==0 || !bag_find(&vers, rid) ) continue;
    zTagname += 4;
    printf("tag %s\n", zTagname);
    printf("from :%d\n", rid);
    printf("tagger <tagger> %lld +0000\n", secSince1970);
    printf("data 0\n");
  }
  db_finalize(&q);
  bag_clear(&vers);
}

** Also test Fossil's ability to measure attributes of a file.
*/
void cmd_test_canonical_name(void){
  int i;
  Blob x;
  blob_zero(&x);
  for(i=2; i<g.argc; i++){
    char zBuf[100];
    const char *zName = g.argv[i];
    file_canonical_name(zName, &x);
    printf("%s\n", blob_buffer(&x));
    blob_reset(&x);
    sqlite3_snprintf(sizeof(zBuf), zBuf, "%lld", file_size(zName));
    printf("  file_size   = %s\n", zBuf);
    printf("  file_size   = %lld\n", file_size(zName));
    sqlite3_snprintf(sizeof(zBuf), zBuf, "%lld", file_mtime(zName));
    printf("  file_mtime  = %s\n", zBuf);
    printf("  file_mtime  = %lld\n", file_mtime(zName));
    printf("  file_isfile = %d\n", file_isfile(zName));
    printf("  file_isexe  = %d\n", file_isexe(zName));
    printf("  file_isdir  = %d\n", file_isdir(zName));
  }
}

/*

** false, then simply return 0.
**
** The root of the tree is defined by the g.zLocalRoot variable.
*/
int file_tree_name(const char *zOrigName, Blob *pOut, int errFatal){
  int n;
  Blob full;
  int nFull;
  char *zFull;

  blob_zero(pOut);
  db_must_be_within_tree();
  file_canonical_name(zOrigName, &full);
  n = strlen(g.zLocalRoot);
  assert( n>0 && g.zLocalRoot[n-1]=='/' );
  nFull = blob_size(&full);
  zFull = blob_buffer(&full);

  /* Special case.  zOrigName refers to g.zLocalRoot directory. */
  if( nFull==n-1 && memcmp(g.zLocalRoot, zFull, nFull)==0 ){
    blob_append(pOut, ".", 1);
    return 1;
  }

  if( nFull<=n || memcmp(g.zLocalRoot, zFull, n) ){
  if( blob_size(&full)<=n || memcmp(g.zLocalRoot, blob_buffer(&full), n) ){
    blob_reset(&full);
    if( errFatal ){
      fossil_fatal("file outside of checkout tree: %s", zOrigName);
    }
    return 0;
  }
  blob_zero(pOut);
  blob_append(pOut, &zFull[n], nFull-n);
  blob_append(pOut, blob_buffer(&full)+n, blob_size(&full)-n);
  return 1;
}

/*
** COMMAND:  test-tree-name
**
** Test the operation of the tree name generator.

*/
#include "config.h"
#include "finfo.h"

/*
** COMMAND: finfo
** 
** Usage: %fossil finfo {?-l|--log? / -s|--status / --p|--print} FILENAME
** Usage: %fossil finfo FILENAME
**
** Print the complete change history for a single file going backwards
** Print the change history for a single file.
** in time.  The default is -l.
**
** For the -l|--log option: If "-b|--brief" is specified one line per revision
** is printed, otherwise the full comment is printed.  The "--limit N"
** and "--offset P" options limits the output to the first N changes
** after skipping P changes.
** The "--limit N" and "--offset P" options limit the output to the first
** N changes after skipping P changes.
**
** In the -s form prints the status as <status> <revision>.  This is
** a quick status and does not check for up-to-date-ness of the file.
**
** The -p form, there's an optional flag "-r|--revision REVISION".  The
** specified version (or the latest checked out version) is printed to
** stdout.
*/
void finfo_cmd(void){
  Stmt q;
  int vid;
  Blob dest;
  const char *zFilename;
  const char *zLimit;
  const char *zOffset;
  int iLimit, iOffset;

  db_must_be_within_tree();
  vid = db_lget_int("checkout", 0);
  if( vid==0 ){
    fossil_panic("no checkout to finfo files in");
  }
  vfile_check_signature(vid, 1);
  if (find_option("status","s",0)) {
    Stmt q;
    Blob line;
    Blob fname;

  zLimit = find_option("limit",0,1);
  iLimit = zLimit ? atoi(zLimit) : -1;
  zOffset = find_option("offset",0,1);
  iOffset = zOffset ? atoi(zOffset) : 0;
  if (g.argc<3) {
    usage("FILENAME");
  }
    if( g.argc!=3 ) usage("-s|--status FILENAME");
    file_tree_name(g.argv[2], &fname, 1);
  file_tree_name(g.argv[2], &dest, 1);
    db_prepare(&q,
        "SELECT pathname, deleted, rid, chnged, coalesce(origname!=pathname,0)"
        "  FROM vfile WHERE vfile.pathname=%B", &fname);
    blob_zero(&line);
    if ( db_step(&q)==SQLITE_ROW ) {
      Blob uuid;
      int isDeleted = db_column_int(&q, 1);
      int isNew = db_column_int(&q,2) == 0;
      int chnged = db_column_int(&q,3);
      int renamed = db_column_int(&q,4);

      blob_zero(&uuid);
      db_blob(&uuid,
           "SELECT uuid FROM blob, mlink, vfile WHERE "
           "blob.rid = mlink.mid AND mlink.fid = vfile.rid AND "
           "vfile.pathname=%B",
           &fname
      );
      if( isNew ){
        blob_appendf(&line, "new");
      }else if( isDeleted ){
        blob_appendf(&line, "deleted");
      }else if( renamed ){
        blob_appendf(&line, "renamed");
      }else if( chnged ){
        blob_appendf(&line, "edited");
      }else{
        blob_appendf(&line, "unchanged");
      }
      blob_appendf(&line, " ");
      blob_appendf(&line, " %10.10s", blob_str(&uuid));
      blob_reset(&uuid);
    }else{
      blob_appendf(&line, "unknown 0000000000");
    }
    db_finalize(&q);
    printf("%s\n", blob_str(&line));
    blob_reset(&fname);
  zFilename = blob_str(&dest);
  db_prepare(&q,
    blob_reset(&line);
  }else if( find_option("print","p",0) ){
    Blob record;
    Blob fname;
    "SELECT "
    "       (SELECT uuid FROM blob WHERE rid=mlink.fid),"  /* New file */
    const char *zRevision = find_option("revision", "r", 1);

    "       (SELECT uuid FROM blob WHERE rid=mlink.mid),"  /* The check-in */
    file_tree_name(g.argv[2], &fname, 1);
    if( zRevision ){
    "       date(event.mtime,'localtime'),"
    "       coalesce(event.ecomment, event.comment),"
    "       coalesce(event.euser, event.user)"
    "  FROM mlink, event"
      historical_version_of_file(zRevision, blob_str(&fname), &record, 0);
    }else{
      int rid = db_int(0, "SELECT rid FROM vfile WHERE pathname=%B", &fname);
      if( rid==0 ){
    " WHERE mlink.fnid=(SELECT fnid FROM filename WHERE name=%Q)"
    "   AND event.objid=mlink.mid"
        fossil_fatal("no history for file: %b", &fname);
      }
      content_get(rid, &record);
    }
    blob_write_to_file(&record, "-");
    blob_reset(&record);
    blob_reset(&fname);
    " ORDER BY event.mtime DESC LIMIT %d OFFSET %d /*sort*/",
    zFilename, iLimit, iOffset
  );
  }else{
    Blob line;
    Stmt q;
    Blob fname;
    int rid;
    const char *zFilename;
    const char *zLimit;
    const char *zOffset;
    int iLimit, iOffset, iBrief;

    if( find_option("log","l",0) ){
      /* this is the default, no-op */
    }
    zLimit = find_option("limit",0,1);
    iLimit = zLimit ? atoi(zLimit) : -1;
    zOffset = find_option("offset",0,1);
    iOffset = zOffset ? atoi(zOffset) : 0;
    iBrief = (find_option("brief","b",0) == 0);
    if( g.argc!=3 ){
      usage("?-l|--log? ?-b|--brief? FILENAME");
    }
    file_tree_name(g.argv[2], &fname, 1);
    rid = db_int(0, "SELECT rid FROM vfile WHERE pathname=%B", &fname);
    if( rid==0 ){
      fossil_fatal("no history for file: %b", &fname);
    }
    zFilename = blob_str(&fname);
    db_prepare(&q,
        "SELECT b.uuid, ci.uuid, date(event.mtime,'localtime'),"
        "       coalesce(event.ecomment, event.comment),"
        "       coalesce(event.euser, event.user)"
        "  FROM mlink, blob b, event, blob ci"
        " WHERE mlink.fnid=(SELECT fnid FROM filename WHERE name=%Q)"
        "   AND b.rid=mlink.fid"
        "   AND event.objid=mlink.mid"
 
        "   AND event.objid=ci.rid"
        " ORDER BY event.mtime DESC LIMIT %d OFFSET %d",
        zFilename, iLimit, iOffset
    );
    blob_zero(&line);
    if( iBrief ){
      printf("History of %s\n", blob_str(&fname));
  printf("History of %s\n", zFilename);
    }
    while( db_step(&q)==SQLITE_ROW ){
      const char *zFileUuid = db_column_text(&q, 0);
      const char *zCiUuid = db_column_text(&q,1);
      const char *zDate = db_column_text(&q, 2);
      const char *zCom = db_column_text(&q, 3);
      const char *zUser = db_column_text(&q, 4);
      char *zOut;
  while( db_step(&q)==SQLITE_ROW ){
    const char *zFileUuid = db_column_text(&q, 0);
    const char *zCiUuid = db_column_text(&q, 1);
    const char *zDate = db_column_text(&q, 2);
    const char *zCom = db_column_text(&q, 3);
    const char *zUser = db_column_text(&q, 4);
    char *zOut;
      if( iBrief ){
        printf("%s ", zDate);
        zOut = sqlite3_mprintf("[%.10s] %s (user: %s, artifact: [%.10s])",
                               zCiUuid, zCom, zUser, zFileUuid);
        comment_print(zOut, 11, 79);
        sqlite3_free(zOut);
    printf("%s ", zDate);
    if( zFileUuid==0 ){
      zOut = sqlite3_mprintf("[%.10s] DELETED %s (user: %s)",
                              zCiUuid, zCom, zUser);
    }else{
      zOut = sqlite3_mprintf("[%.10s] %s (user: %s, artifact: [%.10s])",
                              zCiUuid, zCom, zUser, zFileUuid);
    }
    comment_print(zOut, 11, 79);
    sqlite3_free(zOut);
      }else{
        blob_reset(&line);
        blob_appendf(&line, "%.10s ", zCiUuid);
        blob_appendf(&line, "%.10s ", zDate);
        blob_appendf(&line, "%8.8s ", zUser);
        blob_appendf(&line,"%-40.40s\n", zCom );
        comment_print(blob_str(&line), 0, 79);
      }
  }
    }
    db_finalize(&q);
    blob_reset(&fname);
  db_finalize(&q);
  blob_reset(&dest);
  }
}


/*
** WEBPAGE: finfo
** URL: /finfo?name=FILENAME
**

  blob_zero(&title);
  blob_appendf(&title, "History of ");
  hyperlinked_path(zFilename, &title, 0);
  @ <h2>%b(&title)</h2>
  blob_reset(&title);
  pGraph = graph_init();
  @ <div id="canvas" style="position:relative;width:1px;height:1px;"></div>
  @ <table id="timelineTable" class="timelineTable">
  @ <table class="timelineTable">
  while( db_step(&q)==SQLITE_ROW ){
    const char *zDate = db_column_text(&q, 0);
    const char *zCom = db_column_text(&q, 1);
    const char *zUser = db_column_text(&q, 2);
    int fpid = db_column_int(&q, 3);
    int frid = db_column_int(&q, 4);
    const char *zPUuid = db_column_text(&q, 5);

        i--;
      }
    }
  }

  /* Find the pChild pointer for each node. 
  **
  ** The pChild points to the node directly above on the same rail.
  ** The pChild points to node directly above on the same rail.
  ** The pChild must be in the same branch.  Leaf nodes have a NULL
  ** pChild.
  **
  ** In the case of a fork, choose the pChild that results in the
  ** longest rail.
  */
  for(pRow=p->pFirst; pRow; pRow=pRow->pNext){

        pRow->railInUse = 1<<pRow->iRail;
        continue;
      }
      pRow->iRail = findFreeRail(p, 0, pParent->idx, inUse, pParent->iRail);
      pParent->aiRaiser[pRow->iRail] = pRow->idx;
    }
    mask = 1<<pRow->iRail;
/*    if( pRow->pPrev ) pRow->pPrev->railInUse |= mask; */
    if( pRow->pPrev ) pRow->pPrev->railInUse |= mask;
    if( pRow->pNext ) pRow->pNext->railInUse |= mask;
    if( pRow->pChild==0 ){
      inUse &= ~mask;
    }else{
      inUse |= mask;
      assignChildrenToRail(pRow);
    }

  blob_zero(pHdr);
  i = strlen(g.urlPath);
  if( i>0 && g.urlPath[i-1]=='/' ){
    zSep = "";
  }else{
    zSep = "/";
  }
  blob_appendf(pHdr, "POST %s%sxfer/xfer HTTP/1.0\r\n", g.urlPath, zSep);
  blob_appendf(pHdr, "POST %s%sxfer HTTP/1.0\r\n", g.urlPath, zSep);
  if( g.urlProxyAuth ){
    blob_appendf(pHdr, "Proxy-Authorization: %s\n", g.urlProxyAuth);
  }
  blob_appendf(pHdr, "Host: %s\r\n", g.urlHostname);
  blob_appendf(pHdr, "User-Agent: Fossil/" MANIFEST_VERSION "\r\n");
  if( g.fHttpTrace ){
    blob_appendf(pHdr, "Content-Type: application/x-fossil-debug\r\n");

** in pRecv.  pRecv is assumed to be uninitialized when
** this routine is called - this routine will initialize it.
**
** The server address is contain in the "g" global structure.  The
** url_parse() routine should have been called prior to this routine
** in order to fill this structure appropriately.
*/
int http_exchange(Blob *pSend, Blob *pReply, int useLogin){
void http_exchange(Blob *pSend, Blob *pReply, int useLogin){
  Blob login;           /* The login card */
  Blob payload;         /* The complete payload including login card */
  Blob hdr;             /* The HTTP request header */
  int closeConnection;  /* True to close the connection when done */
  int iLength;          /* Length of the reply payload */
  int rc;               /* Result code */
  int iHttpVersion;     /* Which version of HTTP protocol server uses */
  char *zLine;          /* A single line of the reply header */
  int i;                /* Loop counter */
  int isError = 0;      /* True if the reply is an error message */

  if( transport_open() ){
    fossil_warning(transport_errmsg());
    fossil_fatal(transport_errmsg());
    return 1;
  }

  /* Construct the login card and prepare the complete payload */
  blob_zero(&login);
  if( useLogin ) http_build_login_card(pSend, &login);
  if( g.fHttpTrace ){
    payload = login;

    /* printf("[%s]\n", zLine); fflush(stdout); */
    if( strncasecmp(zLine, "http/1.", 7)==0 ){
      if( sscanf(zLine, "HTTP/1.%d %d", &iHttpVersion, &rc)!=2 ) goto write_err;
      if( rc!=200 && rc!=302 ){
        int ii;
        for(ii=7; zLine[ii] && zLine[ii]!=' '; ii++){}
        while( zLine[ii]==' ' ) ii++;
        fossil_warning("server says: %s", &zLine[ii]);
        fossil_fatal("server says: %s\n", &zLine[ii]);
        goto write_err;
      }
      if( iHttpVersion==0 ){
        closeConnection = 1;
      }else{
        closeConnection = 0;
      }

        closeConnection = 0;
      }
    }else if( rc==302 && strncasecmp(zLine, "location:", 9)==0 ){
      int i, j;
      for(i=9; zLine[i] && zLine[i]==' '; i++){}
      if( zLine[i]==0 ) fossil_fatal("malformed redirect: %s", zLine);
      j = strlen(zLine) - 1; 
      while( j>4 && strcmp(&zLine[j-4],"/xfer")==0 ){
      if( j>4 && strcmp(&zLine[j-4],"/xfer")==0 ) zLine[j-4] = 0;
         j -= 4;
         zLine[j] = 0;
      }
      fossil_print("redirect to %s\n", &zLine[i]);
      url_parse(&zLine[i]);
      transport_close();
      return http_exchange(pSend, pReply, useLogin);
      http_exchange(pSend, pReply, useLogin);
      return;
    }else if( strncasecmp(zLine, "content-type: text/html", 23)==0 ){
      isError = 1;
    }
  }
  if( rc!=200 ){
    fossil_warning("\"location:\" missing from 302 redirect reply");
    fossil_fatal("\"location:\" missing from 302 redirect reply");
    goto write_err;
  }

  /*
  ** Extract the reply payload that follows the header
  */
  if( iLength<0 ){

  */
  closeConnection = 1; /* FIX ME */
  if( closeConnection ){
    transport_close();
  }else{
    transport_rewind();
  }
  return 0;
  return;

  /* 
  ** Jump to here if an error is seen.
  */
write_err:
  transport_close();
  return 1;  
  return;  
}

      struct hostent *pHost;
      pHost = gethostbyname(g.urlName);
      if( pHost!=0 ){
        memcpy(&addr.sin_addr,pHost->h_addr_list[0],pHost->h_length);
      }else
#endif
      {
        socket_set_errmsg("can't resolve host name: %s", g.urlName);
        socket_set_errmsg("can't resolve host name: %s\n", g.urlName);
        return 1;
      }
    }
    addrIsInit = 1;

    /* Set the Global.zIpAddr variable to the server we are talking to.
    ** This is used to populate the ipaddr column of the rcvfrom table,

void transport_flip(void){
  if( g.urlIsSsh ){
    fprintf(sshOut, "\n\n");
  }else if( g.urlIsFile ){
    char *zCmd;
    fclose(transport.pFile);
    zCmd = mprintf("\"%s\" http \"%s\" \"%s\" \"%s\" 127.0.0.1",
       fossil_nameofexe(), g.urlName, transport.zOutFile, transport.zInFile
       g.argv[0], g.urlName, transport.zOutFile, transport.zInFile
    );
    fossil_system(zCmd);
    portable_system(zCmd);
    free(zCmd);
    transport.pFile = fopen(transport.zInFile, "rb");
  }
}

/*
** This routine is called when the inbound message has been received

/*
** Copyright (c) 2010 D. Richard Hipp
**
** This program is free software; you can redistribute it and/or
** modify it under the terms of the Simplified BSD License (also
** known as the "2-Clause License" or "FreeBSD License".)

** This program is distributed in the hope that it will be useful,
** but without any warranty; without even the implied warranty of
** merchantability or fitness for a particular purpose.
**
** Author contact information:
**   drh@sqlite.org
**
*******************************************************************************
**
** This file contains code used to import the content of a Git 
** repository in the git-fast-import format as a new Fossil
** repository.
*/
#include "config.h"
#include "import.h"
#include <assert.h>

#if INTERFACE
/*
** A single file change record.
*/
struct ImportFile { 
  char *zName;           /* Name of a file */
  char *zUuid;           /* UUID of the file */
  char *zPrior;          /* Prior name if the name was changed */
  char isFrom;           /* True if obtained from the parent */
  char isExe;            /* True if executable */
};
#endif


/*
** State information about an on-going fast-import parse.
*/
static struct {
  void (*xFinish)(void);      /* Function to finish a prior record */
  int nData;                  /* Bytes of data */
  char *zTag;                 /* Name of a tag */
  char *zBranch;              /* Name of a branch for a commit */
  char *aData;                /* Data content */
  char *zMark;                /* The current mark */
  char *zDate;                /* Date/time stamp */
  char *zUser;                /* User name */
  char *zComment;             /* Comment of a commit */
  char *zFrom;                /* from value as a UUID */
  char *zFromMark;            /* The mark of the "from" field */
  int nMerge;                 /* Number of merge values */
  int nMergeAlloc;            /* Number of slots in azMerge[] */
  char **azMerge;             /* Merge values */
  int nFile;                  /* Number of aFile values */
  int nFileAlloc;             /* Number of slots in aFile[] */
  ImportFile *aFile;          /* Information about files in a commit */
  int fromLoaded;             /* True zFrom content loaded into aFile[] */
} gg;

/*
** A no-op "xFinish" method
*/
static void finish_noop(void){}
   
/*
** Deallocate the state information.
**
** The azMerge[] and aFile[] arrays are zeroed by allocated space is
** retained unless the freeAll flag is set.
*/
static void import_reset(int freeAll){
  int i;
  gg.xFinish = 0;
  fossil_free(gg.zTag); gg.zTag = 0;
  fossil_free(gg.zBranch); gg.zBranch = 0;
  fossil_free(gg.aData); gg.aData = 0;
  fossil_free(gg.zMark); gg.zMark = 0;
  fossil_free(gg.zDate); gg.zDate = 0;
  fossil_free(gg.zUser); gg.zUser = 0;
  fossil_free(gg.zComment); gg.zComment = 0;
  fossil_free(gg.zFrom); gg.zFrom = 0;
  fossil_free(gg.zFromMark); gg.zFromMark = 0;
  for(i=0; i<gg.nMerge; i++){
    fossil_free(gg.azMerge[i]); gg.azMerge[i] = 0;
  }
  gg.nMerge = 0;
  for(i=0; i<gg.nFile; i++){
    fossil_free(gg.aFile[i].zName);
    fossil_free(gg.aFile[i].zUuid);
    fossil_free(gg.aFile[i].zPrior);
  }
  memset(gg.aFile, 0, gg.nFile*sizeof(gg.aFile[0]));
  gg.nFile = 0;
  if( freeAll ){
    fossil_free(gg.azMerge);
    fossil_free(gg.aFile);
    memset(&gg, 0, sizeof(gg));
  }
  gg.xFinish = finish_noop;
}

/*
** Insert an artifact into the BLOB table if it isn't there already.
** If zMark is not zero, create a cross-reference from that mark back
** to the newly inserted artifact.
*/
static int fast_insert_content(Blob *pContent, const char *zMark){
  Blob hash;
  Blob cmpr;
  int rid;

  sha1sum_blob(pContent, &hash);
  rid = db_int(0, "SELECT rid FROM blob WHERE uuid=%B", &hash);
  if( rid==0 ){
    static Stmt ins;
    db_static_prepare(&ins,
        "INSERT INTO blob(uuid, size, content) VALUES(:uuid, :size, :content)"
    );
    db_bind_text(&ins, ":uuid", blob_str(&hash));
    db_bind_int(&ins, ":size", gg.nData);
    blob_compress(pContent, &cmpr);
    db_bind_blob(&ins, ":content", &cmpr);
    db_step(&ins);
    db_reset(&ins);
    blob_reset(&cmpr);
    rid = db_last_insert_rowid();
  }
  if( zMark ){
    db_multi_exec(
        "INSERT INTO xtag(tname, trid, tuuid)"
        "VALUES(%Q,%d,%B)", 
        zMark, rid, &hash
    );
    db_multi_exec(
        "INSERT INTO xtag(tname, trid, tuuid)"
        "VALUES(%B,%d,%B)", 
        &hash, rid, &hash
    );
  }
  blob_reset(&hash);
  return rid;
}

/*
** Use data accumulated in gg from a "blob" record to add a new file
** to the BLOB table.
*/
static void finish_blob(void){
  Blob content;
  blob_init(&content, gg.aData, gg.nData);
  fast_insert_content(&content, gg.zMark);
  blob_reset(&content);
  import_reset(0);
}

/*
** Use data accumulated in gg from a "tag" record to add a new 
** control artifact to the BLOB table.
*/
static void finish_tag(void){
  Blob record, cksum;
  if( gg.zDate && gg.zTag && gg.zFrom && gg.zUser ){
    blob_zero(&record);
    blob_appendf(&record, "D %s\n", gg.zDate);
    blob_appendf(&record, "T +%F %s\n", gg.zTag, gg.zFrom);
    blob_appendf(&record, "U %F\n", gg.zUser);
    md5sum_blob(&record, &cksum);
    blob_appendf(&record, "Z %b\n", &cksum);
    fast_insert_content(&record, 0);
    blob_reset(&record);
    blob_reset(&cksum);
  }
  import_reset(0);
}

/*
** Compare two ImportFile objects for sorting
*/
static int mfile_cmp(const void *pLeft, const void *pRight){
  const ImportFile *pA = (const ImportFile*)pLeft;
  const ImportFile *pB = (const ImportFile*)pRight;
  return strcmp(pA->zName, pB->zName);
}

/* Forward reference */
static void import_prior_files(void);

/*
** Use data accumulated in gg from a "commit" record to add a new 
** manifest artifact to the BLOB table.
*/
static void finish_commit(void){
  int i;
  char *zFromBranch;
  Blob record, cksum;
  import_prior_files();
  qsort(gg.aFile, gg.nFile, sizeof(gg.aFile[0]), mfile_cmp);
  blob_zero(&record);
  blob_appendf(&record, "C %F\n", gg.zComment);
  blob_appendf(&record, "D %s\n", gg.zDate);
  for(i=0; i<gg.nFile; i++){
    const char *zUuid = gg.aFile[i].zUuid;
    if( zUuid==0 ) continue;
    blob_appendf(&record, "F %F %s", gg.aFile[i].zName, zUuid);
    if( gg.aFile[i].isExe ){
      blob_append(&record, " x\n", 3);
    }else{
      blob_append(&record, "\n", 1);
    }
  }
  if( gg.zFrom ){
    blob_appendf(&record, "P %s", gg.zFrom);
    for(i=0; i<gg.nMerge; i++){
      blob_appendf(&record, " %s", gg.azMerge[i]);
    }
    blob_append(&record, "\n", 1);
    zFromBranch = db_text(0, "SELECT brnm FROM xbranch WHERE tname=%Q",
                              gg.zFromMark);
  }else{
    zFromBranch = 0;
  }
  if( zFromBranch==0 || strcmp(zFromBranch, gg.zBranch)!=0 ){
    blob_appendf(&record, "T *branch * %F\n", gg.zBranch);
    blob_appendf(&record, "T *sym-%F *\n", gg.zBranch);
    if( zFromBranch ){
      blob_appendf(&record, "T -sym-%F *\n", zFromBranch);
    }
  }
  free(zFromBranch);
  if( gg.zFrom==0 ){
    blob_appendf(&record, "T +sym-trunk *\n");
  }
  db_multi_exec("INSERT INTO xbranch(tname, brnm) VALUES(%Q,%Q)",
                gg.zMark, gg.zBranch);
  blob_appendf(&record, "U %F\n", gg.zUser);
  md5sum_blob(&record, &cksum);
  blob_appendf(&record, "Z %b\n", &cksum);
  fast_insert_content(&record, gg.zMark);
  blob_reset(&record);
  blob_reset(&cksum);
  import_reset(0);  
  import_reset(0);
}

/*
** Turn the first \n in the input string into a \000
*/
static void trim_newline(char *z){
  while( z[0] && z[0]!='\n' ){ z++; }
  z[0] = 0;
}

/*
** Duplicate a string.
*/
static char *import_strdup(const char *zOrig){
  char *z = 0;
  if( zOrig ){
    int n = strlen(zOrig);
    z = fossil_malloc( n+1 );
    memcpy(z, zOrig, n+1);
  }
  return z;
}

/*
** Get a token from a line of text.  Return a pointer to the first
** character of the token and zero-terminate the token.  Make
** *pzIn point to the first character past the end of the zero
** terminator, or at the zero-terminator at EOL.
*/
static char *next_token(char **pzIn){
  char *z = *pzIn;
  int i;
  if( z[0]==0 ) return z;
  for(i=0; z[i] && z[i]!=' ' && z[i]!='\n'; i++){}
  if( z[i] ){
    z[i] = 0;
    *pzIn = &z[i+1];
  }else{
    *pzIn = &z[i];
  }
  return z;
}

/*
** Convert a "mark" or "committish" into the UUID.
*/
static char *resolve_committish(const char *zCommittish){
  char *zRes;

  zRes = db_text(0, "SELECT tuuid FROM xtag WHERE tname=%Q", zCommittish);
  return zRes;
}

/*
** Create a new entry in the gg.aFile[] array
*/
static ImportFile *import_add_file(void){
  ImportFile *pFile;
  if( gg.nFile>=gg.nFileAlloc ){
    gg.nFileAlloc = gg.nFileAlloc*2 + 100;
    gg.aFile = fossil_realloc(gg.aFile, gg.nFileAlloc*sizeof(gg.aFile[0]));
  }
  pFile = &gg.aFile[gg.nFile++];
  memset(pFile, 0, sizeof(*pFile));
  return pFile;
}


/*
** Load all file information out of the gg.zFrom check-in
*/
static void import_prior_files(void){
  Manifest *p;
  int rid;
  ManifestFile *pOld;
  ImportFile *pNew;
  if( gg.fromLoaded ) return;
  gg.fromLoaded = 1;
  if( gg.zFrom==0 ) return;
  rid = fast_uuid_to_rid(gg.zFrom);
  if( rid==0 ) return;
  p = manifest_get(rid, CFTYPE_MANIFEST);
  if( p==0 ) return;
  manifest_file_rewind(p);
  while( (pOld = manifest_file_next(p, 0))!=0 ){
    pNew = import_add_file();
    pNew->zName = import_strdup(pOld->zName);
    pNew->isExe = pOld->zPerm && strstr(pOld->zPerm, "x")!=0;
    pNew->zUuid = import_strdup(pOld->zUuid);
    pNew->isFrom = 1;
  }
  manifest_destroy(p);
}

/*
** Locate a file in the gg.aFile[] array by its name.  Begin the search
** with the *pI-th file.  Update *pI to be one past the file found.
** Do not search past the mx-th file.
*/
static ImportFile *import_find_file(const char *zName, int *pI, int mx){
  int i = *pI;
  int nName = strlen(zName);
  while( i<mx ){
    const char *z = gg.aFile[i].zName;
    if( memcmp(zName, z, nName)==0 && (z[nName]==0 || z[nName]=='/') ){
      *pI = i+1;
      return &gg.aFile[i];
    }
    i++;
  }
  return 0;
}


/*
** Read the git-fast-import format from pIn and insert the corresponding
** content into the database.
*/
static void git_fast_import(FILE *pIn){
  ImportFile *pFile, *pNew;
  int i, mx;
  char *z;
  char *zUuid;
  char *zName;
  char *zPerm;
  char *zFrom;
  char *zTo;
  char zLine[1000];

  gg.xFinish = finish_noop;
  while( fgets(zLine, sizeof(zLine), pIn) ){
    if( zLine[0]=='\n' || zLine[0]=='#' ) continue;
    if( memcmp(zLine, "blob", 4)==0 ){
      gg.xFinish();
      gg.xFinish = finish_blob;
    }else
    if( memcmp(zLine, "commit ", 7)==0 ){
      gg.xFinish();
      gg.xFinish = finish_commit;
      trim_newline(&zLine[7]);
      z = &zLine[7];
      for(i=strlen(z)-1; i>=0 && z[i]!='/'; i--){}
      if( z[i+1]!=0 ) z += i+1;
      gg.zBranch = import_strdup(z);
      gg.fromLoaded = 0;
    }else
    if( memcmp(zLine, "tag ", 4)==0 ){
      gg.xFinish();
      gg.xFinish = finish_tag;
      trim_newline(&zLine[4]);
      gg.zTag = import_strdup(&zLine[4]);
    }else
    if( memcmp(zLine, "reset ", 4)==0 ){
      gg.xFinish();
    }else
    if( memcmp(zLine, "checkpoint", 10)==0 ){
      gg.xFinish();
    }else
    if( memcmp(zLine, "feature", 7)==0 ){
      gg.xFinish();
    }else
    if( memcmp(zLine, "option", 6)==0 ){
      gg.xFinish();
    }else
    if( memcmp(zLine, "progress ", 9)==0 ){
      gg.xFinish();
      trim_newline(&zLine[9]);
      printf("%s\n", &zLine[9]);
      fflush(stdout);
    }else
    if( memcmp(zLine, "data ", 5)==0 ){
      fossil_free(gg.aData); gg.aData = 0;
      gg.nData = atoi(&zLine[5]);
      if( gg.nData ){
        int got;
        gg.aData = fossil_malloc( gg.nData+1 );
        got = fread(gg.aData, 1, gg.nData, pIn);
        if( got!=gg.nData ){
          fossil_fatal("short read: got %d of %d bytes", got, gg.nData);
        }
        gg.aData[got] = 0;
        if( gg.zComment==0 && gg.xFinish==finish_commit ){
          gg.zComment = gg.aData;
          gg.aData = 0;
          gg.nData = 0;
        }
      }
    }else
    if( memcmp(zLine, "author ", 7)==0 ){
      /* No-op */
    }else
    if( memcmp(zLine, "mark ", 5)==0 ){
      trim_newline(&zLine[5]);
      fossil_free(gg.zMark);
      gg.zMark = import_strdup(&zLine[5]);
    }else
    if( memcmp(zLine, "tagger ", 7)==0 || memcmp(zLine, "committer ",10)==0 ){
      sqlite3_int64 secSince1970;
      for(i=0; zLine[i] && zLine[i]!='<'; i++){}
      if( zLine[i]==0 ) goto malformed_line;
      z = &zLine[i+1];
      for(i=i+1; zLine[i] && zLine[i]!='>'; i++){}
      if( zLine[i]==0 ) goto malformed_line;
      zLine[i] = 0;
      fossil_free(gg.zUser);
      gg.zUser = import_strdup(z);
      secSince1970 = 0;
      for(i=i+2; fossil_isdigit(zLine[i]); i++){
        secSince1970 = secSince1970*10 + zLine[i] - '0';
      }
      fossil_free(gg.zDate);
      gg.zDate = db_text(0, "SELECT datetime(%lld, 'unixepoch')", secSince1970);
      gg.zDate[10] = 'T';
    }else
    if( memcmp(zLine, "from ", 5)==0 ){
      trim_newline(&zLine[5]);
      fossil_free(gg.zFromMark);
      gg.zFromMark = import_strdup(&zLine[5]);
      fossil_free(gg.zFrom);
      gg.zFrom = resolve_committish(&zLine[5]);
    }else
    if( memcmp(zLine, "merge ", 6)==0 ){
      trim_newline(&zLine[6]);
      if( gg.nMerge>=gg.nMergeAlloc ){
        gg.nMergeAlloc = gg.nMergeAlloc*2 + 10;
        gg.azMerge = fossil_realloc(gg.azMerge, gg.nMergeAlloc*sizeof(char*));
      }
      gg.azMerge[gg.nMerge] = resolve_committish(&zLine[6]);
      if( gg.azMerge[gg.nMerge] ) gg.nMerge++;
    }else
    if( memcmp(zLine, "M ", 2)==0 ){
      import_prior_files();
      z = &zLine[2];
      zPerm = next_token(&z);
      zUuid = next_token(&z);
      zName = next_token(&z);
      i = 0;
      pFile = import_find_file(zName, &i, gg.nFile);
      if( pFile==0 ){
        pFile = import_add_file();
        pFile->zName = import_strdup(zName);
      }
      pFile->isExe = (strcmp(zPerm, "100755")==0);
      fossil_free(pFile->zUuid);
      pFile->zUuid = resolve_committish(zUuid);
      pFile->isFrom = 0;
    }else
    if( memcmp(zLine, "D ", 2)==0 ){
      import_prior_files();
      z = &zLine[2];
      zName = next_token(&z);
      i = 0;
      while( (pFile = import_find_file(zName, &i, gg.nFile))!=0 ){
        if( pFile->isFrom==0 ) continue;
        fossil_free(pFile->zName);
        fossil_free(pFile->zPrior);
        fossil_free(pFile->zUuid);
        *pFile = gg.aFile[--gg.nFile];
        i--;
      }
    }else
    if( memcmp(zLine, "C ", 2)==0 ){
      int nFrom;
      import_prior_files();
      z = &zLine[2];
      zFrom = next_token(&z);
      zTo = next_token(&z);
      i = 0;
      mx = gg.nFile;
      nFrom = strlen(zFrom);
      while( (pFile = import_find_file(zFrom, &i, mx))!=0 ){
        if( pFile->isFrom==0 ) continue;
        pNew = import_add_file();
        pFile = &gg.aFile[i-1];
        if( strlen(pFile->zName)>nFrom ){
          pNew->zName = mprintf("%s%s", zTo, pFile->zName[nFrom]);
        }else{
          pNew->zName = import_strdup(pFile->zName);
        }
        pNew->isExe = pFile->isExe;
        pNew->zUuid = import_strdup(pFile->zUuid);
        pNew->isFrom = 0;
      }
    }else
    if( memcmp(zLine, "R ", 2)==0 ){
      int nFrom;
      import_prior_files();
      z = &zLine[2];
      zFrom = next_token(&z);
      zTo = next_token(&z);
      i = 0;
      nFrom = strlen(zFrom);
      while( (pFile = import_find_file(zFrom, &i, gg.nFile))!=0 ){
        if( pFile->isFrom==0 ) continue;
        pNew = import_add_file();
        pFile = &gg.aFile[i-1];
        if( strlen(pFile->zName)>nFrom ){
          pNew->zName = mprintf("%s%s", zTo, pFile->zName[nFrom]);
        }else{
          pNew->zName = import_strdup(pFile->zName);
        }
        pNew->zPrior = pFile->zName;
        pNew->isExe = pFile->isExe;
        pNew->zUuid = pFile->zUuid;
        pNew->isFrom = 0;
        gg.nFile--;
        *pFile = *pNew;
        memset(pNew, 0, sizeof(*pNew));
      }
      fossil_fatal("cannot handle R records, use --full-tree");
    }else
    if( memcmp(zLine, "deleteall", 9)==0 ){
      gg.fromLoaded = 1;
    }else
    if( memcmp(zLine, "N ", 2)==0 ){
      /* No-op */
    }else

    {
      goto malformed_line;
    }
  }
  gg.xFinish();
  import_reset(1);
  return;

malformed_line:
  trim_newline(zLine);
  fossil_fatal("bad fast-import line: [%s]", zLine);
  return;
}

/*
** COMMAND: import
**
** Usage: %fossil import NEW-REPOSITORY
**
** Read text generated by the git-fast-export command and use it to
** construct a new Fossil repository named by the NEW-REPOSITORY
** argument.  The get-fast-export text is read from standard input.
*/
void git_import_cmd(void){
  char *zPassword;
  FILE *pIn;
  int forceFlag = find_option("force", "f", 0)!=0;
  if( g.argc!=3  && g.argc!=4 ){
    usage("REPOSITORY-NAME");
  }
  if( g.argc==4 ){
    pIn = fopen(g.argv[3], "rb");
  }else{
    pIn = stdin;
    fossil_binary_mode(pIn);
  }
  if( forceFlag ) unlink(g.argv[2]);
  db_create_repository(g.argv[2]);
  db_open_repository(g.argv[2]);
  db_open_config(0);
  db_multi_exec(
     "CREATE TEMP TABLE xtag(tname TEXT UNIQUE, trid INT, tuuid TEXT);"
     "CREATE TEMP TABLE xbranch(tname TEXT UNIQUE, brnm TEXT);"
  );
  db_begin_transaction();
  db_initial_setup(0, 0, 1);
  git_fast_import(pIn);
  db_end_transaction(0);
  db_begin_transaction();
  printf("Rebuilding repository meta-data...\n");
  rebuild_db(0, 1);
  verify_cancel();
  db_end_transaction(0);
  printf("Vacuuming..."); fflush(stdout);
  db_multi_exec("VACUUM");
  printf(" ok\n");
  printf("project-id: %s\n", db_get("project-code", 0));
  printf("server-id:  %s\n", db_get("server-code", 0));
  zPassword = db_text(0, "SELECT pw FROM user WHERE login=%Q", g.zLogin);
  printf("admin-user: %s (password is \"%s\")\n", g.zLogin, zPassword);
}

** Print common information about a particular record.
**
**     *  The UUID
**     *  The record ID
**     *  mtime and ctime
**     *  who signed it
*/
void show_common_info(
void show_common_info(int rid, const char *zUuidName, int showComment){
  int rid,                   /* The rid for the check-in to display info for */
  const char *zUuidName,     /* Name of the UUID */
  int showComment,           /* True to show the check-in comment */
  int showFamily             /* True to show parents and children */
){
  Stmt q;
  char *zComment = 0;
  char *zTags;
  char *zDate;
  char *zUuid;
  zUuid = db_text(0, "SELECT uuid FROM blob WHERE rid=%d", rid);
  if( zUuid ){
    zDate = db_text(0, 
      "SELECT datetime(mtime) || ' UTC' FROM event WHERE objid=%d",
      rid
    );
         /* 01234567890123 */
    printf("%-13s %s %s\n", zUuidName, zUuid, zDate ? zDate : "");
    free(zUuid);
    free(zDate);
  }
  if( zUuid && showComment ){
    zComment = db_text(0, 
      "SELECT coalesce(ecomment,comment) || "
      "SELECT coalesce(ecomment,comment) || ' (user: ' || coalesce(euser,user,'?') || ')' FROM event WHERE objid=%d",
      "       ' (user: ' || coalesce(euser,user,'?') || ')' "
      "  FROM event WHERE objid=%d",
      rid
    );
  }
  if( showFamily ){
    db_prepare(&q, "SELECT uuid, pid FROM plink JOIN blob ON pid=rid "
                   " WHERE cid=%d", rid);
    while( db_step(&q)==SQLITE_ROW ){
      const char *zUuid = db_column_text(&q, 0);
      zDate = db_text("", 
        "SELECT datetime(mtime) || ' UTC' FROM event WHERE objid=%d",
        db_column_int(&q, 1)
      );
      printf("parent:       %s %s\n", zUuid, zDate);
      free(zDate);
    }
    db_finalize(&q);
    db_prepare(&q, "SELECT uuid, cid FROM plink JOIN blob ON cid=rid "
                   " WHERE pid=%d", rid);
    while( db_step(&q)==SQLITE_ROW ){
      const char *zUuid = db_column_text(&q, 0);
      zDate = db_text("", 
        "SELECT datetime(mtime) || ' UTC' FROM event WHERE objid=%d",
        db_column_int(&q, 1)
      );
      printf("child:        %s %s\n", zUuid, zDate);
      free(zDate);
    }
    db_finalize(&q);
  db_prepare(&q, "SELECT uuid, pid FROM plink JOIN blob ON pid=rid "
                 " WHERE cid=%d", rid);
  while( db_step(&q)==SQLITE_ROW ){
    const char *zUuid = db_column_text(&q, 0);
    zDate = db_text("", 
      "SELECT datetime(mtime) || ' UTC' FROM event WHERE objid=%d",
      db_column_int(&q, 1)
    );
    printf("parent:       %s %s\n", zUuid, zDate);
    free(zDate);
  }
  db_finalize(&q);
  db_prepare(&q, "SELECT uuid, cid FROM plink JOIN blob ON cid=rid "
                 " WHERE pid=%d", rid);
  while( db_step(&q)==SQLITE_ROW ){
    const char *zUuid = db_column_text(&q, 0);
    zDate = db_text("", 
      "SELECT datetime(mtime) || ' UTC' FROM event WHERE objid=%d",
      db_column_int(&q, 1)
    );
    printf("child:        %s %s\n", zUuid, zDate);
    free(zDate);
  }
  db_finalize(&q);
  }
  zTags = info_tags_of_checkin(rid, 0);
  if( zTags && zTags[0] ){
    printf("tags:         %s\n", zTags);
  }
  free(zTags);
  if( zComment ){
    printf("comment:      ");

#endif
    printf("project-code: %s\n", db_get("project-code", ""));
    printf("server-code:  %s\n", db_get("server-code", ""));
    vid = db_lget_int("checkout", 0);
    if( vid==0 ){
      printf("checkout:     nil\n");
    }else{
      show_common_info(vid, "checkout:", 1, 1);
      show_common_info(vid, "checkout:", 1);
    }
  }else{
    int rid;
    rid = name_to_rid(g.argv[2]);
    if( rid==0 ){
      fossil_panic("no such object: %s\n", g.argv[2]);
    }
    show_common_info(rid, "uuid:", 1, 1);
    show_common_info(rid, "uuid:", 1);
  }
}

/*
** Show information about all tags on a given node.
*/
static void showTags(int rid, const char *zNotGlob){

/*
** Return the name of the login cookie
*/
static char *login_cookie_name(void){
  static char *zCookieName = 0;
  if( zCookieName==0 ){
    unsigned int h = 0;
    const char *z = g.zBaseURL;
    while( *z ){ h = (h<<3) ^ (h>>26) ^ *(z++); }
    zCookieName = mprintf("fossil_login_%08x", h);
    int n = strlen(g.zTop);
    zCookieName = fossil_malloc( n*2+16 );
                      /* 0123456789 12345 */
    strcpy(zCookieName, "fossil_login_");
    encode16((unsigned char*)g.zTop, (unsigned char*)&zCookieName[13], n);
  }
  return zCookieName;
}

/*
** Redirect to the page specified by the "g" query parameter.
** Or if there is no "g" query parameter, redirect to the homepage.

void login_set_anon_nobody_capabilities(void){
  static int once = 1;
  if( g.zLogin && once ){
    const char *zCap;
    /* All logged-in users inherit privileges from "nobody" */
    zCap = db_text("", "SELECT cap FROM user WHERE login = 'nobody'");
    login_set_capabilities(zCap);
    if( strcmp(g.zLogin, "nobody")!=0 ){
    if( strcmp(g.zLogin, "anonymous")!=0 ){
      /* All logged-in users inherit privileges from "anonymous" */
      zCap = db_text("", "SELECT cap FROM user WHERE login = 'anonymous'");
      login_set_capabilities(zCap);
    }
    once = 0;
  }
}

  int idx;
  int rc;

  sqlite3_config(SQLITE_CONFIG_LOG, fossil_sqlite_log, 0);
  g.now = time(0);
  g.argc = argc;
  g.argv = argv;
  if( getenv("GATEWAY_INTERFACE")!=0 && !find_option("nocgi", 0, 0)){
  if( getenv("GATEWAY_INTERFACE")!=0 ){
    zCmdName = "cgi";
  }else if( argc<2 ){
    fprintf(stderr, "Usage: %s COMMAND ...\n"
                    "\"%s help\" for a list of available commands\n"
                    "\"%s help COMMAND\" for specific details\n",
                    argv[0], argv[0], argv[0]);
    fossil_exit(1);

/*
** The following variable becomes true while processing a fatal error
** or a panic.  If additional "recursive-fatal" errors occur while
** shutting down, the recursive errors are silently ignored.
*/
static int mainInFatalError = 0;

/*
** Return the name of the current executable.
*/
const char *fossil_nameofexe(void){
#ifdef _WIN32
  return _pgmptr;
#else
  return g.argv[0];
#endif
}

/*
** Exit.  Take care to close the database first.
*/
void fossil_exit(int rc){
  db_close();
  exit(rc);
}

  z = vmprintf(zFormat, ap);
  va_end(ap);
  if( g.cgiOutput && once ){
    once = 0;
    cgi_printf("<p class=\"generalError\">%h</p>", z);
    cgi_reply();
  }else{
    fprintf(stderr, "%s: %s\n", fossil_nameofexe(), z);
    fprintf(stderr, "%s: %s\n", g.argv[0], z);
  }
  db_force_rollback();
  fossil_exit(1);
}
void fossil_fatal(const char *zFormat, ...){
  char *z;
  va_list ap;
  mainInFatalError = 1;
  va_start(ap, zFormat);
  z = vmprintf(zFormat, ap);
  va_end(ap);
  if( g.cgiOutput ){
    g.cgiOutput = 0;
    cgi_printf("<p class=\"generalError\">%h</p>", z);
    cgi_reply();
  }else{
    fprintf(stderr, "\r%s: %s\n", fossil_nameofexe(), z);
    fprintf(stderr, "%s: %s\n", g.argv[0], z);
  }
  db_force_rollback();
  fossil_exit(1);
}

/* This routine works like fossil_fatal() except that if called
** recursively, the recursive call is a no-op.

  z = vmprintf(zFormat, ap);
  va_end(ap);
  if( g.cgiOutput ){
    g.cgiOutput = 0;
    cgi_printf("<p class=\"generalError\">%h</p>", z);
    cgi_reply();
  }else{
    fprintf(stderr, "\r%s: %s\n", fossil_nameofexe(), z);
    fprintf(stderr, "%s: %s\n", g.argv[0], z);
  }
  db_force_rollback();
  fossil_exit(1);
}


/* Print a warning message */
void fossil_warning(const char *zFormat, ...){
  char *z;
  va_list ap;
  va_start(ap, zFormat);
  z = vmprintf(zFormat, ap);
  va_end(ap);
  if( g.cgiOutput ){
    cgi_printf("<p class=\"generalError\">%h</p>", z);
  }else{
    fprintf(stderr, "\r%s: %s\n", fossil_nameofexe(), z);
    fprintf(stderr, "%s: %s\n", g.argv[0], z);
  }
}

/*
** Malloc and free routines that cannot fail
*/
void *fossil_malloc(size_t n){
  void *p = malloc(n);
  if( p==0 ) fossil_panic("out of memory");
  return p;
}
void fossil_free(void *p){
  free(p);
}
void *fossil_realloc(void *p, size_t n){
  p = realloc(p, n);
  if( p==0 ) fossil_panic("out of memory");
  return p;
}

/*
** This function implements a cross-platform "system()" interface.
*/
int fossil_system(const char *zOrigCmd){
  int rc;
#if defined(_WIN32)
  /* On windows, we have to put double-quotes around the entire command.
  ** Who knows why - this is just the way windows works.
  */
  char *zNewCmd = mprintf("\"%s\"", zOrigCmd);
  rc = system(zNewCmd);
  free(zNewCmd);
#else
  /* On unix, evaluate the command directly.
  */
  rc = system(zOrigCmd);
#endif 
  return rc; 
}

/*
** Turn off any NL to CRNL translation on the stream given as an
** argument.  This is a no-op on unix but is necessary on windows.
*/
void fossil_binary_mode(FILE *p){
#if defined(_WIN32)
  _setmode(_fileno(p), _O_BINARY);
#endif
}



/*
** Return a name for an SQLite error code
*/
static const char *sqlite_error_code_name(int iCode){
  static char zCode[30];

  fossil_warning("%s: %s", sqlite_error_code_name(iCode), zErrmsg);
}

/*
** Print a usage comment and quit
*/
void usage(const char *zFormat){
  fprintf(stderr, "Usage: %s %s %s\n", fossil_nameofexe(), g.argv[1], zFormat);
  fprintf(stderr, "Usage: %s %s %s\n", g.argv[0], g.argv[1], zFormat);
  fossil_exit(1);
}

/*
** Remove n elements from g.argv beginning with the i-th element.
*/
void remove_from_argv(int i, int n){

**
** Display information on how to use COMMAND
*/
void help_cmd(void){
  int rc, idx;
  const char *z;
  if( g.argc!=3 ){
    printf("Usage: %s help COMMAND.\nAvailable COMMANDs:\n",
    printf("Usage: %s help COMMAND.\nAvailable COMMANDs:\n", g.argv[0]);
           fossil_nameofexe());
    cmd_cmd_list();
    version_cmd();
    return;
  }
  rc = name_search(g.argv[2], aCommand, count(aCommand), &idx);
  if( rc==1 ){
    fossil_fatal("unknown command: %s", g.argv[2]);
  }else if( rc==2 ){
    fossil_fatal("ambiguous command prefix: %s", g.argv[2]);
  }
  z = aCmdHelp[idx];
  if( z==0 ){
    fossil_fatal("no help available for the %s command",
       aCommand[idx].zName);
  }
  while( *z ){
    if( *z=='%' && strncmp(z, "%fossil", 7)==0 ){
      printf("%s", fossil_nameofexe());
      printf("%s", g.argv[0]);
      z += 7;
    }else{
      putchar(*z);
      z++;
    }
  }
  putchar('\n');

  $(SRCDIR)/deltacmd.c \
  $(SRCDIR)/descendants.c \
  $(SRCDIR)/diff.c \
  $(SRCDIR)/diffcmd.c \
  $(SRCDIR)/doc.c \
  $(SRCDIR)/encode.c \
  $(SRCDIR)/event.c \
  $(SRCDIR)/export.c \
  $(SRCDIR)/file.c \
  $(SRCDIR)/finfo.c \
  $(SRCDIR)/graph.c \
  $(SRCDIR)/http.c \
  $(SRCDIR)/http_socket.c \
  $(SRCDIR)/http_ssl.c \
  $(SRCDIR)/http_transport.c \
  $(SRCDIR)/import.c \
  $(SRCDIR)/info.c \
  $(SRCDIR)/login.c \
  $(SRCDIR)/main.c \
  $(SRCDIR)/manifest.c \
  $(SRCDIR)/md5.c \
  $(SRCDIR)/merge.c \
  $(SRCDIR)/merge3.c \

  deltacmd_.c \
  descendants_.c \
  diff_.c \
  diffcmd_.c \
  doc_.c \
  encode_.c \
  event_.c \
  export_.c \
  file_.c \
  finfo_.c \
  graph_.c \
  http_.c \
  http_socket_.c \
  http_ssl_.c \
  http_transport_.c \
  import_.c \
  info_.c \
  login_.c \
  main_.c \
  manifest_.c \
  md5_.c \
  merge_.c \
  merge3_.c \

 $(OBJDIR)/deltacmd.o \
 $(OBJDIR)/descendants.o \
 $(OBJDIR)/diff.o \
 $(OBJDIR)/diffcmd.o \
 $(OBJDIR)/doc.o \
 $(OBJDIR)/encode.o \
 $(OBJDIR)/event.o \
 $(OBJDIR)/export.o \
 $(OBJDIR)/file.o \
 $(OBJDIR)/finfo.o \
 $(OBJDIR)/graph.o \
 $(OBJDIR)/http.o \
 $(OBJDIR)/http_socket.o \
 $(OBJDIR)/http_ssl.o \
 $(OBJDIR)/http_transport.o \
 $(OBJDIR)/import.o \
 $(OBJDIR)/info.o \
 $(OBJDIR)/login.o \
 $(OBJDIR)/main.o \
 $(OBJDIR)/manifest.o \
 $(OBJDIR)/md5.o \
 $(OBJDIR)/merge.o \
 $(OBJDIR)/merge3.o \

#
$(SRCDIR)/../manifest:	
	# noop

clean:	
	rm -f $(OBJDIR)/*.o *_.c $(APPNAME) VERSION.h
	rm -f translate makeheaders mkindex page_index.h headers
	rm -f add.h allrepo.h attach.h bag.h blob.h branch.h browse.h captcha.h cgi.h checkin.h checkout.h clearsign.h clone.h comformat.h configure.h content.h db.h delta.h deltacmd.h descendants.h diff.h diffcmd.h doc.h encode.h event.h export.h file.h finfo.h graph.h http.h http_socket.h http_ssl.h http_transport.h import.h info.h login.h main.h manifest.h md5.h merge.h merge3.h name.h pivot.h popen.h pqueue.h printf.h rebuild.h report.h rss.h schema.h search.h setup.h sha1.h shun.h skins.h stat.h style.h sync.h tag.h th_main.h timeline.h tkt.h tktsetup.h undo.h update.h url.h user.h verify.h vfile.h wiki.h wikiformat.h winhttp.h xfer.h zip.h
	rm -f add.h allrepo.h attach.h bag.h blob.h branch.h browse.h captcha.h cgi.h checkin.h checkout.h clearsign.h clone.h comformat.h configure.h content.h db.h delta.h deltacmd.h descendants.h diff.h diffcmd.h doc.h encode.h event.h file.h finfo.h graph.h http.h http_socket.h http_ssl.h http_transport.h info.h login.h main.h manifest.h md5.h merge.h merge3.h name.h pivot.h popen.h pqueue.h printf.h rebuild.h report.h rss.h schema.h search.h setup.h sha1.h shun.h skins.h stat.h style.h sync.h tag.h th_main.h timeline.h tkt.h tktsetup.h undo.h update.h url.h user.h verify.h vfile.h wiki.h wikiformat.h winhttp.h xfer.h zip.h

page_index.h: $(TRANS_SRC) mkindex
	./mkindex $(TRANS_SRC) >$@
headers:	page_index.h makeheaders VERSION.h
	./makeheaders  add_.c:add.h allrepo_.c:allrepo.h attach_.c:attach.h bag_.c:bag.h blob_.c:blob.h branch_.c:branch.h browse_.c:browse.h captcha_.c:captcha.h cgi_.c:cgi.h checkin_.c:checkin.h checkout_.c:checkout.h clearsign_.c:clearsign.h clone_.c:clone.h comformat_.c:comformat.h configure_.c:configure.h content_.c:content.h db_.c:db.h delta_.c:delta.h deltacmd_.c:deltacmd.h descendants_.c:descendants.h diff_.c:diff.h diffcmd_.c:diffcmd.h doc_.c:doc.h encode_.c:encode.h event_.c:event.h export_.c:export.h file_.c:file.h finfo_.c:finfo.h graph_.c:graph.h http_.c:http.h http_socket_.c:http_socket.h http_ssl_.c:http_ssl.h http_transport_.c:http_transport.h import_.c:import.h info_.c:info.h login_.c:login.h main_.c:main.h manifest_.c:manifest.h md5_.c:md5.h merge_.c:merge.h merge3_.c:merge3.h name_.c:name.h pivot_.c:pivot.h popen_.c:popen.h pqueue_.c:pqueue.h printf_.c:printf.h rebuild_.c:rebuild.h report_.c:report.h rss_.c:rss.h schema_.c:schema.h search_.c:search.h setup_.c:setup.h sha1_.c:sha1.h shun_.c:shun.h skins_.c:skins.h stat_.c:stat.h style_.c:style.h sync_.c:sync.h tag_.c:tag.h th_main_.c:th_main.h timeline_.c:timeline.h tkt_.c:tkt.h tktsetup_.c:tktsetup.h undo_.c:undo.h update_.c:update.h url_.c:url.h user_.c:user.h verify_.c:verify.h vfile_.c:vfile.h wiki_.c:wiki.h wikiformat_.c:wikiformat.h winhttp_.c:winhttp.h xfer_.c:xfer.h zip_.c:zip.h $(SRCDIR)/sqlite3.h $(SRCDIR)/th.h VERSION.h
	./makeheaders  add_.c:add.h allrepo_.c:allrepo.h attach_.c:attach.h bag_.c:bag.h blob_.c:blob.h branch_.c:branch.h browse_.c:browse.h captcha_.c:captcha.h cgi_.c:cgi.h checkin_.c:checkin.h checkout_.c:checkout.h clearsign_.c:clearsign.h clone_.c:clone.h comformat_.c:comformat.h configure_.c:configure.h content_.c:content.h db_.c:db.h delta_.c:delta.h deltacmd_.c:deltacmd.h descendants_.c:descendants.h diff_.c:diff.h diffcmd_.c:diffcmd.h doc_.c:doc.h encode_.c:encode.h event_.c:event.h file_.c:file.h finfo_.c:finfo.h graph_.c:graph.h http_.c:http.h http_socket_.c:http_socket.h http_ssl_.c:http_ssl.h http_transport_.c:http_transport.h info_.c:info.h login_.c:login.h main_.c:main.h manifest_.c:manifest.h md5_.c:md5.h merge_.c:merge.h merge3_.c:merge3.h name_.c:name.h pivot_.c:pivot.h popen_.c:popen.h pqueue_.c:pqueue.h printf_.c:printf.h rebuild_.c:rebuild.h report_.c:report.h rss_.c:rss.h schema_.c:schema.h search_.c:search.h setup_.c:setup.h sha1_.c:sha1.h shun_.c:shun.h skins_.c:skins.h stat_.c:stat.h style_.c:style.h sync_.c:sync.h tag_.c:tag.h th_main_.c:th_main.h timeline_.c:timeline.h tkt_.c:tkt.h tktsetup_.c:tktsetup.h undo_.c:undo.h update_.c:update.h url_.c:url.h user_.c:user.h verify_.c:verify.h vfile_.c:vfile.h wiki_.c:wiki.h wikiformat_.c:wikiformat.h winhttp_.c:winhttp.h xfer_.c:xfer.h zip_.c:zip.h $(SRCDIR)/sqlite3.h $(SRCDIR)/th.h VERSION.h
	touch headers
headers: Makefile
Makefile:
add_.c:	$(SRCDIR)/add.c translate
	./translate $(SRCDIR)/add.c >add_.c

$(OBJDIR)/add.o:	add_.c add.h  $(SRCDIR)/config.h

event_.c:	$(SRCDIR)/event.c translate
	./translate $(SRCDIR)/event.c >event_.c

$(OBJDIR)/event.o:	event_.c event.h  $(SRCDIR)/config.h
	$(XTCC) -o $(OBJDIR)/event.o -c event_.c

event.h:	headers
export_.c:	$(SRCDIR)/export.c translate
	./translate $(SRCDIR)/export.c >export_.c

$(OBJDIR)/export.o:	export_.c export.h  $(SRCDIR)/config.h
	$(XTCC) -o $(OBJDIR)/export.o -c export_.c

export.h:	headers
file_.c:	$(SRCDIR)/file.c translate
	./translate $(SRCDIR)/file.c >file_.c

$(OBJDIR)/file.o:	file_.c file.h  $(SRCDIR)/config.h
	$(XTCC) -o $(OBJDIR)/file.o -c file_.c

file.h:	headers

http_transport_.c:	$(SRCDIR)/http_transport.c translate
	./translate $(SRCDIR)/http_transport.c >http_transport_.c

$(OBJDIR)/http_transport.o:	http_transport_.c http_transport.h  $(SRCDIR)/config.h
	$(XTCC) -o $(OBJDIR)/http_transport.o -c http_transport_.c

http_transport.h:	headers
import_.c:	$(SRCDIR)/import.c translate
	./translate $(SRCDIR)/import.c >import_.c

$(OBJDIR)/import.o:	import_.c import.h  $(SRCDIR)/config.h
	$(XTCC) -o $(OBJDIR)/import.o -c import_.c

import.h:	headers
info_.c:	$(SRCDIR)/info.c translate
	./translate $(SRCDIR)/info.c >info_.c

$(OBJDIR)/info.o:	info_.c info.h  $(SRCDIR)/config.h
	$(XTCC) -o $(OBJDIR)/info.o -c info_.c

info.h:	headers

  deltacmd
  descendants
  diff
  diffcmd
  doc
  encode
  event
  export
  file
  finfo
  graph
  http
  http_socket
  http_transport
  import
  info
  login
  main
  manifest
  md5
  merge
  merge3

#define MX_MANIFEST_CACHE 6
static struct {
  int nxAge;
  int aAge[MX_MANIFEST_CACHE];
  Manifest *apManifest[MX_MANIFEST_CACHE];
} manifestCache;

/*
** True if manifest_crosslink_begin() has been called but
** manifest_crosslink_end() is still pending.
*/
static int manifest_crosslink_busy = 0;

/*
** Clear the memory allocated in a manifest object
*/
void manifest_destroy(Manifest *p){
  if( p ){
    blob_reset(&p->content);

}

#ifdef FOSSIL_DONT_VERIFY_MANIFEST_MD5SUM
# define md5sum_init(X)
# define md5sum_step_text(X,Y)
#endif

/*
** Return true if z points to the first character after a blank line.
** Tolerate either \r\n or \n line endings.
*/
static int after_blank_line(const char *z){
  if( z[-1]!='\n' ) return 0;
  if( z[-2]=='\n' ) return 1;
  if( z[-2]=='\r' && z[-3]=='\n' ) return 1;
  return 0;
}

/*
** Remove the PGP signature from the artifact, if there is one.
*/
static void remove_pgp_signature(char **pz, int *pn){
  char *z = *pz;
  int n = *pn;
  int i;
  if( memcmp(z, "-----BEGIN PGP SIGNED MESSAGE-----", 34)!=0 ) return;
  for(i=34; i<n && !after_blank_line(z+i); i++){}
  for(i=34; i<n && (z[i-1]!='\n' || z[i-2]!='\n'); i++){}
  if( i>=n ) return;
  z += i;
  n -= i;
  *pz = z;
  for(i=n-1; i>=0; i--){
    if( z[i]=='\n' && memcmp(&z[i],"\n-----BEGIN PGP SIGNATURE-", 25)==0 ){
      n = i+1;

    if( p->zTicketUuid ) goto manifest_syntax_error;
    if( p->zWikiTitle ) goto manifest_syntax_error;
    if( !seenZ ) goto manifest_syntax_error;
    p->type = CFTYPE_ATTACHMENT;
  }else{
    if( p->nCChild>0 ) goto manifest_syntax_error;
    if( p->rDate<=0.0 ) goto manifest_syntax_error;
    if( p->nParent>0 ) goto manifest_syntax_error;
    if( p->nField>0 ) goto manifest_syntax_error;
    if( p->zTicketUuid ) goto manifest_syntax_error;
    if( p->zWikiTitle ) goto manifest_syntax_error;
    if( p->zTicketUuid ) goto manifest_syntax_error;
    p->type = CFTYPE_MANIFEST;
  }
  md5sum_init();

    return;
  }
  if( (pParent->zBaseline==0)==(pChild->zBaseline==0) ){
    content_deltify(pid, cid, 0); 
  }else if( pChild->zBaseline==0 && pParent->zBaseline!=0 ){
    content_deltify(pParent->pBaseline->rid, cid, 0);
  }

  /* Remember all children less than 2 seconds younger than their parent,
  ** as we might want to fudge the times for those children.
  */
  if( pChild->rDate<pParent->rDate+2.3e-5 && manifest_crosslink_busy ){
    db_multi_exec(
       "INSERT OR REPLACE INTO time_fudge VALUES(%d, %.17g, %d, %.17g);",
       pParent->rid, pParent->rDate, pChild->rid, pChild->rDate
    );
  }
  
  for(i=0, pChildFile=pChild->aFile; i<pChild->nFile; i++, pChildFile++){
    if( pChildFile->zPrior ){
       pParentFile = manifest_file_seek(pParent, pChildFile->zPrior);
       if( pParentFile ){
         add_one_mlink(cid, pParentFile->zUuid, pChildFile->zUuid,
                       pChildFile->zName, pChildFile->zPrior);

    for(i=0, pParentFile=pParent->aFile; i<pParent->nFile; i++, pParentFile++){
      if( pParentFile->zUuid ) continue;
      pChildFile = manifest_file_seek(pChild, pParentFile->zName);
      if( pChildFile ){
        add_one_mlink(cid, 0, pChildFile->zUuid, pChildFile->zName, 0);
      }
    }
  }else if( pChild->zBaseline==0 ){
    manifest_file_rewind(pParent);
    while( (pParentFile = manifest_file_next(pParent,0))!=0 ){
      pChildFile = manifest_file_seek(pChild, pParentFile->zName);
      if( pChildFile==0 ){
        add_one_mlink(cid, pParentFile->zUuid, 0, pParentFile->zName, 0);
      }
    }
  }
  manifest_cache_insert(*ppOther);
}

/*
** True if manifest_crosslink_begin() has been called but
** manifest_crosslink_end() is still pending.
*/
static int manifest_crosslink_busy = 0;

/*
** Setup to do multiple manifest_crosslink() calls.
** This is only required if processing ticket changes.
*/
void manifest_crosslink_begin(void){
  assert( manifest_crosslink_busy==0 );
  manifest_crosslink_busy = 1;
  db_begin_transaction();
  db_multi_exec(
     "CREATE TEMP TABLE pending_tkt(uuid TEXT UNIQUE);"
  db_multi_exec("CREATE TEMP TABLE pending_tkt(uuid TEXT UNIQUE)");
     "CREATE TEMP TABLE time_fudge("
     "  mid INTEGER PRIMARY KEY,"
     "  m1 REAL,"
     "  cid INTEGER,"
     "  m2 REAL"
     ");"
  );
}

/*
** Finish up a sequence of manifest_crosslink calls.
*/
void manifest_crosslink_end(void){
  Stmt q, u;
  Stmt q;
  int i;
  assert( manifest_crosslink_busy==1 );
  db_prepare(&q, "SELECT uuid FROM pending_tkt");
  while( db_step(&q)==SQLITE_ROW ){
    const char *zUuid = db_column_text(&q, 0);
    ticket_rebuild_entry(zUuid);
  }
  db_finalize(&q);
  db_multi_exec("DROP TABLE pending_tkt");

  db_prepare(&q, "UPDATE time_fudge SET m1=m2-2.8935e-7 WHERE m1>=m2");
  db_prepare(&u, "UPDATE time_fudge SET m2="
        "(SELECT x.m1 FROM time_fudge AS x WHERE x.mid=time_fudge.cid)");
  for(i=0; i<30; i++){
    db_step(&q);
    db_reset(&q);
    if( sqlite3_changes(g.db)==0 ) break;
    db_step(&u);
    db_reset(&u);
  }
  db_finalize(&q);
  db_finalize(&u);
  db_multi_exec(
    "UPDATE event SET mtime=(SELECT m1 FROM time_fudge WHERE mid=objid)"
    " WHERE objid IN (SELECT mid FROM time_fudge);"
    "DROP TABLE time_fudge;"
  );

  db_end_transaction(0);
  manifest_crosslink_busy = 0;
}

/*
** Make an entry in the event table for a ticket change artifact.
*/

      }
      db_prepare(&q, "SELECT cid FROM plink WHERE pid=%d AND isprim", rid);
      while( db_step(&q)==SQLITE_ROW ){
        int cid = db_column_int(&q, 0);
        add_mlink(rid, p, cid, 0);
      }
      db_finalize(&q);
      if( p->nParent==0 ){
        for(i=0; i<p->nFile; i++){
          add_one_mlink(rid, 0, p->aFile[i].zUuid, p->aFile[i].zName, 0);
        }
      }
      db_multi_exec(
        "REPLACE INTO event(type,mtime,objid,user,comment,"
                           "bgcolor,euser,ecomment)"
        "VALUES('ci',"
        "  coalesce("
        "    (SELECT julianday(value) FROM tagxref WHERE tagid=%d AND rid=%d),"
        "    %.17g"

  if( vid==0 ){
    fossil_fatal("nothing is checked out");
  }
  mid = name_to_rid(g.argv[2]);
  if( mid==0 ){
    fossil_fatal("not a version: %s", g.argv[2]);
  }
  if( !is_a_version(mid) ){
  if( mid>1 && !db_exists("SELECT 1 FROM plink WHERE cid=%d", mid) ){
    fossil_fatal("not a version: %s", g.argv[2]);
  }
  if( pickFlag || backoutFlag ){
    pid = db_int(0, "SELECT pid FROM plink WHERE cid=%d AND isprim", mid);
    if( pid<=0 ){
      fossil_fatal("cannot find an ancestor for %s", g.argv[2]);
    }

    db_prepare(&q, "SELECT merge FROM vmerge WHERE id=0");
    while( db_step(&q)==SQLITE_ROW ){
      pivot_set_secondary(db_column_int(&q,0));
    }
    db_finalize(&q);
    pid = pivot_find();
    if( pid<=0 ){
      fossil_fatal("cannot find a common ancestor between the current "
      fossil_fatal("cannot find a common ancestor between the current"
                   "checkout and %s", g.argv[2]);
    }
  }
  if( !is_a_version(pid) ){
    fossil_fatal("not a version: record #%d", pid);
  if( pid>1 && !db_exists("SELECT 1 FROM plink WHERE cid=%d", pid) ){
    fossil_fatal("not a version: record #%d", mid);
  }
  vfile_check_signature(vid, 1);
  db_begin_transaction();
  undo_begin();
  load_vfile_from_rid(mid);
  load_vfile_from_rid(pid);

**
** Combine change in going from PIVOT->VERSION1 with the change going
** from PIVOT->VERSION2 and write the combined changes into MERGED.
*/
void delta_3waymerge_cmd(void){
  Blob pivot, v1, v2, merged;
  if( g.argc!=6 ){
    usage("PIVOT V1 V2 MERGED");
    fprintf(stderr,"Usage: %s %s PIVOT V1 V2 MERGED\n", g.argv[0], g.argv[1]);
    fossil_exit(1);
  }
  if( blob_read_from_file(&pivot, g.argv[2])<0 ){
    fprintf(stderr,"cannot read %s\n", g.argv[2]);
    fossil_exit(1);
  }
  if( blob_read_from_file(&v1, g.argv[3])<0 ){
    fprintf(stderr,"cannot read %s\n", g.argv[3]);

**
** An input of "tip" returns the most recent check-in.
**
** Memory to hold the returned string comes from malloc() and needs to
** be freed by the caller.
*/
char *tag_to_uuid(const char *zTag){
  int vid;
  char *zUuid = 
    db_text(0,
       "SELECT blob.uuid"
       "  FROM tag, tagxref, event, blob"
       " WHERE tag.tagname='sym-'||%Q "
       "   AND tagxref.tagid=tag.tagid AND tagxref.tagtype>0 "
       "   AND event.objid=tagxref.rid "

        "SELECT blob.uuid"
        "  FROM event, blob"
        " WHERE event.type='ci'"
        "   AND blob.rid=event.objid"
        " ORDER BY event.mtime DESC"
      );
    }
    if( zUuid==0 && g.localOpen && (vid=db_lget_int("checkout",0))!=0 ){
      if( strcmp(zTag, "current")==0 ){
        zUuid = db_text(0, "SELECT uuid FROM blob WHERE rid=%d", vid);
      }else if( strcmp(zTag, "prev")==0 || strcmp(zTag, "previous")==0 ){
        zUuid = db_text(0, "SELECT uuid FROM blob WHERE rid="
                           "(SELECT pid FROM plink WHERE cid=%d AND isprim)",
                           vid);
      }else if( strcmp(zTag, "next")==0 ){
        zUuid = db_text(0, "SELECT uuid FROM blob WHERE rid="
                           "(SELECT cid FROM plink WHERE pid=%d AND isprim"
                           "  ORDER BY mtime DESC)",
                           vid);
      }
    }
  }
  return zUuid;
}

/*
** Convert a date/time string into a UUID.
**

    "DELETE FROM aqueue;"
    "CREATE INDEX IF NOT EXISTS aqueue_idx1 ON aqueue(pending, mtime);"
  );

  /* Insert the primary record */
  db_multi_exec( 
    "INSERT INTO aqueue(rid, mtime, pending, src)"
    "  SELECT %d, mtime, 1, 1 FROM event WHERE objid=%d AND type='ci' LIMIT 1",
    "  SELECT %d, mtime, 1, 1 FROM plink WHERE cid=%d LIMIT 1",
    rid, rid
  );
}

/*
** Set a secondary file.  The primary file must be set first.  There
** must be at least one secondary but there can be more than one if
** desired.
*/
void pivot_set_secondary(int rid){
  /* Insert the primary record */
  db_multi_exec( 
    "INSERT OR IGNORE INTO aqueue(rid, mtime, pending, src)"
    "  SELECT %d, mtime, 1, 0 FROM event WHERE objid=%d AND type='ci'",
    "  SELECT %d, mtime, 1, 0 FROM plink WHERE cid=%d",
    rid, rid
  );
}

/*
** Find the most recent common ancestor of the primary and one of
** the secondaries.  Return its rid.  Return 0 if no common ancestor

** records.  Run this command after updating the fossil
** executable in a way that changes the database schema.
*/
void rebuild_database(void){
  int forceFlag;
  int randomizeFlag;
  int errCnt;
  int omitVerify;

  omitVerify = find_option("noverify",0,0)!=0;
  forceFlag = find_option("force","f",0)!=0;
  randomizeFlag = find_option("randomize", 0, 0)!=0;
  if( g.argc==3 ){
    db_open_repository(g.argv[2]);
  }else{
    db_find_and_open_repository(1);
    if( g.argc!=2 ){
      usage("?REPOSITORY-FILENAME?");
    }
    db_close();
    db_open_repository(g.zRepositoryName);
  }
  db_begin_transaction();
  ttyOutput = 1;
  errCnt = rebuild_db(randomizeFlag, 1);
  if( errCnt && !forceFlag ){
    printf("%d errors. Rolling back changes. Use --force to force a commit.\n",
            errCnt);
    db_end_transaction(1);
  }else{
    if( omitVerify ) verify_cancel();
    db_end_transaction(0);
  }
}

/*
** COMMAND:  test-detach
**

}

/*
** COMMAND: deconstruct
**
** Usage %fossil deconstruct ?-R|--repository REPOSITORY? ?-L|--prefixlength N? DESTINATION
**
** This command exports all artifacts of a given repository and
** This command exports all artifacts of o given repository and
** writes all artifacts to the file system. The DESTINATION directory
** will be populated with subdirectories AA and files AA/BBBBBBBBB.., where
** AABBBBBBBBB.. is the 40 character artifact ID, AA the first 2 characters.
** If -L|--prefixlength is given, the length (default 2) of the directory
** prefix can be set to 0,1,..,9 characters.
*/
void deconstruct_cmd(void){

  
  /* Compile the statement and check for illegal accesses or syntax errors. */
  sqlite3_set_authorizer(g.db, report_query_authorizer, (void*)&zErr);
  rc = sqlite3_prepare(g.db, zSql, -1, &pStmt, &zTail);
  if( rc!=SQLITE_OK ){
    zErr = mprintf("Syntax error: %s", sqlite3_errmsg(g.db));
  }
  if( !sqlite3_stmt_readonly(pStmt) ){
    zErr = mprintf("SQL must not modify the database");
  }
  if( pStmt ){
    sqlite3_finalize(pStmt);
  }
  sqlite3_set_authorizer(g.db, 0, 0);
  return zErr;
}

  free(zToFree);
  if( horiz ){
    @ </tr>
  }
  @ </table>
}

/*
** Execute a single read-only SQL statement.  Invoke xCallback() on each
** row.
*/
int sqlite3_exec_readonly(
  sqlite3 *db,                /* The database on which the SQL executes */
  const char *zSql,           /* The SQL to be executed */
  sqlite3_callback xCallback, /* Invoke this callback routine */
  void *pArg,                 /* First argument to xCallback() */
  char **pzErrMsg             /* Write error messages here */
){
  int rc = SQLITE_OK;         /* Return code */
  const char *zLeftover;      /* Tail of unprocessed SQL */
  sqlite3_stmt *pStmt = 0;    /* The current SQL statement */
  char **azCols = 0;          /* Names of result columns */
  int nCol;                   /* Number of columns of output */
  char **azVals = 0;          /* Text of all output columns */
  int i;                      /* Loop counter */

  pStmt = 0;
  rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, &zLeftover);
  assert( rc==SQLITE_OK || pStmt==0 );
  if( rc!=SQLITE_OK ){
    return rc;
  }
  if( !pStmt ){
    /* this happens for a comment or white-space */
    return SQLITE_OK;
  }
  if( !sqlite3_stmt_readonly(pStmt) ){
    sqlite3_finalize(pStmt);
    return SQLITE_ERROR;
  }

  nCol = sqlite3_column_count(pStmt);
  azVals = fossil_malloc(2*nCol*sizeof(const char*) + 1);
  while( (rc = sqlite3_step(pStmt))==SQLITE_ROW ){
    if( azCols==0 ){
      azCols = &azVals[nCol];
      for(i=0; i<nCol; i++){
        azCols[i] = (char *)sqlite3_column_name(pStmt, i);
      }
    }
    for(i=0; i<nCol; i++){
      azVals[i] = (char *)sqlite3_column_text(pStmt, i);
    }
    if( xCallback(pArg, nCol, azVals, azCols) ){
      break;
    }
  }
  rc = sqlite3_finalize(pStmt);
  fossil_free(azVals);
  return rc;
}


/*
** WEBPAGE: /rptview
**
** Generate a report.  The rn query parameter is the report number
** corresponding to REPORTFMT.RN.  If the tablist query parameter exists,
** then the output consists of lines of tab-separated fields instead of

    style_header(zTitle);
    output_color_key(zClrKey, 1, 
        "border=\"0\" cellpadding=\"3\" cellspacing=\"0\" class=\"report\"");
    @ <table border="1" cellpadding="2" cellspacing="0" class="report">
    sState.rn = rn;
    sState.nCount = 0;
    sqlite3_set_authorizer(g.db, report_query_authorizer, (void*)&zErr1);
    sqlite3_exec_readonly(g.db, zSql, generate_html, &sState, &zErr2);
    sqlite3_exec(g.db, zSql, generate_html, &sState, &zErr2);
    sqlite3_set_authorizer(g.db, 0, 0);
    @ </table>
    if( zErr1 ){
      @ <p class="reportError">Error: %h(zErr1)</p>
    }else if( zErr2 ){
      @ <p class="reportError">Error: %h(zErr2)</p>
    }
    style_footer();
  }else{
    sqlite3_set_authorizer(g.db, report_query_authorizer, (void*)&zErr1);
    sqlite3_exec_readonly(g.db, zSql, output_tab_separated, &count, &zErr2);
    sqlite3_exec(g.db, zSql, output_tab_separated, &count, &zErr2);
    sqlite3_set_authorizer(g.db, 0, 0);
    cgi_set_content_type("text/plain");
  }
}

/*
** report number for full table ticket export

  if( zFilter ){
    zSql = mprintf("SELECT * FROM (%s) WHERE %s",zSql,zFilter);
  }
  count = 0;
  tktEncode = enc;
  zSep = zSepIn;
  sqlite3_set_authorizer(g.db, report_query_authorizer, (void*)&zErr1);
  sqlite3_exec_readonly(g.db, zSql, output_separated_file, &count, &zErr2);
  sqlite3_exec(g.db, zSql, output_separated_file, &count, &zErr2);
  sqlite3_set_authorizer(g.db, 0, 0);
  if( zFilter ){
    free(zSql);
  }
}

      iVal = iQ;
    }
  }
  if( iVal ){
    @ <input type="checkbox" name="%s(zQParm)" checked="checked" />
    @ <b>%s(zLabel)</b>
  }else{
    @ <input type="checkbox" name="%s(zQParm)" /> <b>%s(zLabel)</b>
    @ <input type="checkbox" name="%s(zQParm)" /><b>%s(zLabel)</b>
  }
}

/*
** Generate an entry box for an attribute.
*/
void entry_attribute(

  @ <form action="%s(g.zBaseURL)/setup_settings" method="post"><div>
  @ <table border="0"><tr><td valign="top">
  login_insert_csrf_secret();
  for(pSet=ctrlSettings; pSet->name!=0; pSet++){
    if( pSet->width==0 ){
      onoff_attribute(pSet->name, pSet->name,
                      pSet->var!=0 ? pSet->var : pSet->name,
                      is_truth(pSet->def));
                      pSet->def[0]=='1');
      @ <br />
    }
  }
  @ </td><td style="width: 30;"></td><td valign="top">
  for(pSet=ctrlSettings; pSet->name!=0; pSet++){
    if( pSet->width!=0 ){
      entry_attribute(pSet->name, /*pSet->width*/ 40, pSet->name,

  db_end_transaction(0);
}

/*
** WEBPAGE: setup_logo
*/
void setup_logo(void){
  const char *zMime = db_get("logo-mimetype","image/gif");
  const char *zMime = "image/gif";
  const char *aImg = P("im");
  int szImg = atoi(PD("im:bytes","0"));
  if( szImg>0 ){
    zMime = PD("im:mimetype","image/gif");
  }
  login_check_credentials();
  if( !g.okSetup ){

/******************************************************************************
** This file is an amalgamation of many separate C source files from SQLite
** version 3.7.4.  By combining all the individual C code files into this 
** version 3.7.3.  By combining all the individual C code files into this 
** single large file, the entire code can be compiled as a one translation
** unit.  This allows many compilers to do optimizations that would not be
** possible if the files were compiled separately.  Performance improvements
** of 5% or more are commonly seen when SQLite is compiled as a single
** of 5% are more are commonly seen when SQLite is compiled as a single
** translation unit.
**
** This file is all you need to compile SQLite.  To use SQLite in other
** programs, you need this file and the "sqlite3.h" header file that defines
** the programming interface to the SQLite library.  (If you do not have 
** the "sqlite3.h" header file at hand, you will find a copy embedded within
** the text of this file.  Search for "Begin file sqlite3.h" to find the start

** string contains the date and time of the check-in (UTC) and an SHA1
** hash of the entire source tree.
**
** See also: [sqlite3_libversion()],
** [sqlite3_libversion_number()], [sqlite3_sourceid()],
** [sqlite_version()] and [sqlite_source_id()].
*/
#define SQLITE_VERSION        "3.7.4"
#define SQLITE_VERSION_NUMBER 3007004
#define SQLITE_SOURCE_ID      "2010-11-16 23:10:26 fd5b2f23dd5111d2f0934dd828bae36b755024c1"
#define SQLITE_VERSION        "3.7.3"
#define SQLITE_VERSION_NUMBER 3007003
#define SQLITE_SOURCE_ID      "2010-10-07 13:29:13 e55ada89246d4cc5f476891c70572dc7c1c3643e"

/*
** CAPI3REF: Run-Time Library Version Numbers
** KEYWORDS: sqlite3_version, sqlite3_sourceid
**
** These interfaces provide the same information as the [SQLITE_VERSION],
** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros

**
** ^This interface can be used to retrieve a saved copy of the original
** SQL text used to create a [prepared statement] if that statement was
** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
*/
SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);

/*
** CAPI3REF: Determine If An SQL Statement Writes The Database
**
** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if
** the [prepared statement] X is guaranteed to leave the database file
** unmodified.  ^If the sqlite3_stmt_readonly(X) interface returns false (zero)
** then evaluating the statement might change the database file, but this
** is not guaranteed as the write operation might be conditional and the
** condition might not be met.  ^If X is a NULL pointer then
** sqlite3_stmt_readonly(X) returns true.  If X is a non-NULL pointer but
** is not a pointer to a valid, unfinalized prepared statement, then the
** behavior is undefined and probably harmful.
*/
SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt);

/*
** CAPI3REF: Dynamically Typed Value Object
** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
**
** SQLite uses the sqlite3_value object to represent all values
** that can be stored in a database table. SQLite uses dynamic typing
** for the values it stores.  ^Values stored in sqlite3_value objects

** number of bytes in the parameter.  To be clear: the value is the
** number of <u>bytes</u> in the value, not the number of characters.)^
** ^If the fourth parameter is negative, the length of the string is
** the number of bytes up to the first zero terminator.
**
** ^The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and
** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
** string after SQLite has finished with it.  ^The destructor is called
** string after SQLite has finished with it. ^If the fifth argument is
** to dispose of the BLOB or string even if the call to sqlite3_bind_blob(),
** sqlite3_bind_text(), or sqlite3_bind_text16() fails.  
** ^If the fifth argument is
** the special value [SQLITE_STATIC], then SQLite assumes that the
** information is in static, unmanaged space and does not need to be freed.
** ^If the fifth argument has the value [SQLITE_TRANSIENT], then
** SQLite makes its own private copy of the data immediately, before
** the sqlite3_bind_*() routine returns.
**
** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that

** aggregate. ^A scalar SQL function requires an implementation of the xFunc
** callback only; NULL pointers must be passed as the xStep and xFinal
** parameters. ^An aggregate SQL function requires an implementation of xStep
** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
** SQL function or aggregate, pass NULL poiners for all three function
** callbacks.
**
** ^(If the tenth parameter to sqlite3_create_function_v2() is not NULL,
** ^If the tenth parameter to sqlite3_create_function_v2() is not NULL,
** then it is destructor for the application data pointer. 
** The destructor is invoked when the function is deleted, either by being
** overloaded or when the database connection closes.)^
** then it is invoked when the function is deleted, either by being
** overloaded or when the database connection closes.
** ^The destructor is also invoked if the call to
** sqlite3_create_function_v2() fails.
** ^When the destructor callback of the tenth parameter is invoked, it
** is passed a single argument which is a copy of the application data 
** pointer which was the fifth parameter to sqlite3_create_function_v2().
** ^When the destructure callback of the tenth parameter is invoked, it
** is passed a single argument which is a copy of the pointer which was
** the fifth parameter to sqlite3_create_function_v2().
**
** ^It is permitted to register multiple implementations of the same
** functions with the same name but with either differing numbers of
** arguments or differing preferred text encodings.  ^SQLite will use
** the implementation that most closely matches the way in which the
** SQL function is used.  ^A function implementation with a non-negative
** nArg parameter is a better match than a function implementation with

** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
** with the addition that the xDestroy callback is invoked on pArg when
** the collating function is deleted.
** ^Collating functions are deleted when they are overridden by later
** calls to the collation creation functions or when the
** [database connection] is closed using [sqlite3_close()].
**
** ^The xDestroy callback is <u>not</u> called if the 
** sqlite3_create_collation_v2() function fails.  Applications that invoke
** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should 
** check the return code and dispose of the application data pointer
** themselves rather than expecting SQLite to deal with it for them.
** This is different from every other SQLite interface.  The inconsistency 
** is unfortunate but cannot be changed without breaking backwards 
** compatibility.
**
** See also:  [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
*/
SQLITE_API int sqlite3_create_collation(
  sqlite3*, 
  const char *zName, 
  int eTextRep, 
  void *pArg,

** parameter is an arbitrary client data pointer that is passed through
** into the [xCreate] and [xConnect] methods of the virtual table module
** when a new virtual table is be being created or reinitialized.
**
** ^The sqlite3_create_module_v2() interface has a fifth parameter which
** is a pointer to a destructor for the pClientData.  ^SQLite will
** invoke the destructor function (if it is not NULL) when SQLite
** no longer needs the pClientData pointer.  ^The destructor will also
** no longer needs the pClientData pointer.  ^The sqlite3_create_module()
** be invoked if the call to sqlite3_create_module_v2() fails.
** ^The sqlite3_create_module()
** interface is equivalent to sqlite3_create_module_v2() with a NULL
** destructor.
*/
SQLITE_API int sqlite3_create_module(
  sqlite3 *db,               /* SQLite connection to register module with */
  const char *zName,         /* Name of the module */
  const sqlite3_module *p,   /* Methods for the module */

  const char *zTable,
  const char *zColumn,
  sqlite3_int64 iRow,
  int flags,
  sqlite3_blob **ppBlob
);

/*
** CAPI3REF: Move a BLOB Handle to a New Row
**
** ^This function is used to move an existing blob handle so that it points
** to a different row of the same database table. ^The new row is identified
** by the rowid value passed as the second argument. Only the row can be
** changed. ^The database, table and column on which the blob handle is open
** remain the same. Moving an existing blob handle to a new row can be
** faster than closing the existing handle and opening a new one.
**
** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] -
** it must exist and there must be either a blob or text value stored in
** the nominated column.)^ ^If the new row is not present in the table, or if
** it does not contain a blob or text value, or if another error occurs, an
** SQLite error code is returned and the blob handle is considered aborted.
** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or
** [sqlite3_blob_reopen()] on an aborted blob handle immediately return
** SQLITE_ABORT.
**
** ^This function sets the database handle error code and message.
*/
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64);

/*
** CAPI3REF: Close A BLOB Handle
**
** ^Closes an open [BLOB handle].
**
** ^Closing a BLOB shall cause the current transaction to commit
** if there are no other BLOBs, no pending prepared statements, and the

    u8 notIndexed;    /* True if there is a NOT INDEXED clause */
    int iCursor;      /* The VDBE cursor number used to access this table */
    Expr *pOn;        /* The ON clause of a join */
    IdList *pUsing;   /* The USING clause of a join */
    Bitmask colUsed;  /* Bit N (1<<N) set if column N of pTab is used */
    char *zIndex;     /* Identifier from "INDEXED BY <zIndex>" clause */
    Index *pIndex;    /* Index structure corresponding to zIndex, if any */
#ifndef SQLITE_OMIT_EXPLAIN
    int iSelectId;    /* If pSelect!=0, the id of the sub-select in EQP */
#endif
  } a[1];             /* One entry for each identifier on the list */
};

/*
** Permitted values of the SrcList.a.jointype field
*/
#define JT_INNER     0x0001    /* Any kind of inner or cross join */

** pTerm is only used when wsFlags&WHERE_MULTI_OR is true.  And pVtabIdx
** is only used when wsFlags&WHERE_VIRTUALTABLE is true.  It is never the
** case that more than one of these conditions is true.
*/
struct WherePlan {
  u32 wsFlags;                   /* WHERE_* flags that describe the strategy */
  u32 nEq;                       /* Number of == constraints */
  double nRow;                   /* Estimated number of rows (for EQP) */
  union {
    Index *pIdx;                   /* Index when WHERE_INDEXED is true */
    struct WhereTerm *pTerm;       /* WHERE clause term for OR-search */
    sqlite3_index_info *pVtabIdx;  /* Virtual table index to use */
  } u;
};

  SrcList *pTabList;             /* List of tables in the join */
  int iTop;                      /* The very beginning of the WHERE loop */
  int iContinue;                 /* Jump here to continue with next record */
  int iBreak;                    /* Jump here to break out of the loop */
  int nLevel;                    /* Number of nested loop */
  struct WhereClause *pWC;       /* Decomposition of the WHERE clause */
  double savedNQueryLoop;        /* pParse->nQueryLoop outside the WHERE loop */
  double nRowOut;                /* Estimated number of output rows */
  WhereLevel a[1];               /* Information about each nest loop in WHERE */
};

/*
** A NameContext defines a context in which to resolve table and column
** names.  The context consists of a list of tables (the pSrcList) field and
** a list of named expression (pEList).  The named expression list may

  Select *pPrior;        /* Prior select in a compound select statement */
  Select *pNext;         /* Next select to the left in a compound */
  Select *pRightmost;    /* Right-most select in a compound select statement */
  Expr *pLimit;          /* LIMIT expression. NULL means not used. */
  Expr *pOffset;         /* OFFSET expression. NULL means not used. */
  int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */
  int addrOpenEphm[3];   /* OP_OpenEphem opcodes related to this select */
  double nSelectRow;     /* Estimated number of result rows */
};

/*
** Allowed values for Select.selFlags.  The "SF" prefix stands for
** "Select Flag".
*/
#define SF_Distinct        0x0001  /* Output should be DISTINCT */

  u8 declareVtab;            /* True if inside sqlite3_declare_vtab() */
  int nVtabLock;             /* Number of virtual tables to lock */
  Table **apVtabLock;        /* Pointer to virtual tables needing locking */
#endif
  int nHeight;            /* Expression tree height of current sub-select */
  Table *pZombieTab;      /* List of Table objects to delete after code gen */
  TriggerPrg *pTriggerPrg;    /* Linked list of coded triggers */

#ifndef SQLITE_OMIT_EXPLAIN
  int iSelectId;
  int iNextSelectId;
#endif
};

#ifdef SQLITE_OMIT_VIRTUALTABLE
  #define IN_DECLARE_VTAB 0
#else
  #define IN_DECLARE_VTAB (pParse->declareVtab)
#endif

){
  int rc = SQLITE_OK;             /* Return Code */
  if( flags & (SQLITE_OPEN_WAL|SQLITE_OPEN_MAIN_JOURNAL) ){
    char zDb[MAX_PATHNAME+1];     /* Database file path */
    int nDb;                      /* Number of valid bytes in zDb */
    struct stat sStat;            /* Output of stat() on database file */

    /* zPath is a path to a WAL or journal file. The following block derives
    ** the path to the associated database file from zPath. This block handles
    ** the following naming conventions:
    **
    **   "<path to db>-journal"
    **   "<path to db>-wal"
    **   "<path to db>-journal-NNNN"
    **   "<path to db>-wal-NNNN"
    **
    ** where NNNN is a 4 digit decimal number. The NNNN naming schemes are 
    ** used by the test_multiplex.c module.
    */
    nDb = sqlite3Strlen30(zPath) - 1; 
    nDb = sqlite3Strlen30(zPath) - ((flags & SQLITE_OPEN_WAL) ? 4 : 8);
    while( nDb>0 && zPath[nDb]!='l' ) nDb--;
    nDb -= ((flags & SQLITE_OPEN_WAL) ? 3 : 7);
    memcpy(zDb, zPath, nDb);
    zDb[nDb] = '\0';

    if( 0==stat(zDb, &sStat) ){
      *pMode = sStat.st_mode & 0777;
    }else{
      rc = SQLITE_IOERR_FSTAT;
    }
  }else if( flags & SQLITE_OPEN_DELETEONCLOSE ){
    *pMode = 0600;

# define sqlite3WalUndo(x,y,z)                 0
# define sqlite3WalSavepoint(y,z)
# define sqlite3WalSavepointUndo(y,z)          0
# define sqlite3WalFrames(u,v,w,x,y,z)         0
# define sqlite3WalCheckpoint(u,v,w,x)         0
# define sqlite3WalCallback(z)                 0
# define sqlite3WalExclusiveMode(y,z)          0
# define sqlite3WalHeapMemory(z)               0
#else

#define WAL_SAVEPOINT_NDATA 4

/* Connection to a write-ahead log (WAL) file. 
** There is one object of this type for each pager. 
*/
typedef struct Wal Wal;

/* Open and close a connection to a write-ahead log. */
SQLITE_PRIVATE int sqlite3WalOpen(sqlite3_vfs*, sqlite3_file*, const char *zName, int, Wal**);
SQLITE_PRIVATE int sqlite3WalOpen(sqlite3_vfs*, sqlite3_file*, const char *zName, Wal**);
SQLITE_PRIVATE int sqlite3WalClose(Wal *pWal, int sync_flags, int, u8 *);

/* Used by readers to open (lock) and close (unlock) a snapshot.  A 
** snapshot is like a read-transaction.  It is the state of the database
** at an instant in time.  sqlite3WalOpenSnapshot gets a read lock and
** preserves the current state even if the other threads or processes
** write to or checkpoint the WAL.  sqlite3WalCloseSnapshot() closes the

SQLITE_PRIVATE int sqlite3WalCallback(Wal *pWal);

/* Tell the wal layer that an EXCLUSIVE lock has been obtained (or released)
** by the pager layer on the database file.
*/
SQLITE_PRIVATE int sqlite3WalExclusiveMode(Wal *pWal, int op);

/* Return true if the argument is non-NULL and the WAL module is using
** heap-memory for the wal-index. Otherwise, if the argument is NULL or the
** WAL module is using shared-memory, return false. 
*/
SQLITE_PRIVATE int sqlite3WalHeapMemory(Wal *pWal);

#endif /* ifndef SQLITE_OMIT_WAL */
#endif /* _WAL_H_ */

/************** End of wal.h *************************************************/
/************** Continuing where we left off in pager.c **********************/

      assert( pPager->errCode!=SQLITE_OK );
      assert( sqlite3PcacheRefCount(pPager->pPCache)>0 );
      break;
  }

  return 1;
}
#endif /* ifndef NDEBUG */

#ifdef SQLITE_DEBUG 
/*
** Return a pointer to a human readable string in a static buffer
** containing the state of the Pager object passed as an argument. This
** is intended to be used within debuggers. For example, as an alternative
** to "print *pPager" in gdb:
**
** (gdb) printf "%s", print_pager_state(pPager)

** Except, if Pager.eLock is set to UNKNOWN_LOCK when this function is
** called, do not modify it. See the comment above the #define of 
** UNKNOWN_LOCK for an explanation of this.
*/
static int pagerUnlockDb(Pager *pPager, int eLock){
  int rc = SQLITE_OK;

  assert( !pPager->exclusiveMode || pPager->eLock==eLock );
  assert( !pPager->exclusiveMode );
  assert( eLock==NO_LOCK || eLock==SHARED_LOCK );
  assert( eLock!=NO_LOCK || pagerUseWal(pPager)==0 );
  if( isOpen(pPager->fd) ){
    assert( pPager->eLock>=eLock );
    rc = sqlite3OsUnlock(pPager->fd, eLock);
    if( pPager->eLock!=UNKNOWN_LOCK ){
      pPager->eLock = (u8)eLock;

      */
      rc = pagerPagecount(pPager, &nPage);
      if( rc==SQLITE_OK ){
        if( nPage==0 ){
          sqlite3BeginBenignMalloc();
          if( pagerLockDb(pPager, RESERVED_LOCK)==SQLITE_OK ){
            sqlite3OsDelete(pVfs, pPager->zJournal, 0);
            if( !pPager->exclusiveMode ) pagerUnlockDb(pPager, SHARED_LOCK);
            pagerUnlockDb(pPager, SHARED_LOCK);
          }
          sqlite3EndBenignMalloc();
        }else{
          /* The journal file exists and no other connection has a reserved
          ** or greater lock on the database file. Now check that there is
          ** at least one non-zero bytes at the start of the journal file.
          ** If there is, then we consider this journal to be hot. If not, 

*/
SQLITE_PRIVATE int sqlite3PagerLockingMode(Pager *pPager, int eMode){
  assert( eMode==PAGER_LOCKINGMODE_QUERY
            || eMode==PAGER_LOCKINGMODE_NORMAL
            || eMode==PAGER_LOCKINGMODE_EXCLUSIVE );
  assert( PAGER_LOCKINGMODE_QUERY<0 );
  assert( PAGER_LOCKINGMODE_NORMAL>=0 && PAGER_LOCKINGMODE_EXCLUSIVE>=0 );
  assert( pPager->exclusiveMode || 0==sqlite3WalHeapMemory(pPager->pWal) );
  if( eMode>=0 && !pPager->tempFile && !sqlite3WalHeapMemory(pPager->pWal) ){
  if( eMode>=0 && !pPager->tempFile ){
    pPager->exclusiveMode = (u8)eMode;
  }
  return (int)pPager->exclusiveMode;
}

/*
** Set the journal-mode for this pager. Parameter eMode must be one of:

/*
** Return true if the underlying VFS for the given pager supports the
** primitives necessary for write-ahead logging.
*/
SQLITE_PRIVATE int sqlite3PagerWalSupported(Pager *pPager){
  const sqlite3_io_methods *pMethods = pPager->fd->pMethods;
  return pPager->exclusiveMode || (pMethods->iVersion>=2 && pMethods->xShmMap);
  return pMethods->iVersion>=2 && pMethods->xShmMap!=0;
}

/*
** Attempt to take an exclusive lock on the database file. If a PENDING lock
** is obtained instead, immediately release it.
*/
static int pagerExclusiveLock(Pager *pPager){
  int rc;                         /* Return code */

  assert( pPager->eLock==SHARED_LOCK || pPager->eLock==EXCLUSIVE_LOCK );
  rc = pagerLockDb(pPager, EXCLUSIVE_LOCK);
  if( rc!=SQLITE_OK ){
    /* If the attempt to grab the pending lock failed, release the 
    ** exclusive lock that may have been obtained instead.  */
    pagerUnlockDb(pPager, SHARED_LOCK);
  }

  return rc;
}

/*
** Call sqlite3WalOpen() to open the WAL handle. If the pager is in 
** exclusive-locking mode when this function is called, take an EXCLUSIVE
** lock on the database file and use heap-memory to store the wal-index
** in. Otherwise, use the normal shared-memory.
*/
static int pagerOpenWal(Pager *pPager){
  int rc = SQLITE_OK;

  assert( pPager->pWal==0 && pPager->tempFile==0 );
  assert( pPager->eLock==SHARED_LOCK || pPager->eLock==EXCLUSIVE_LOCK || pPager->noReadlock);

  /* If the pager is already in exclusive-mode, the WAL module will use 
  ** heap-memory for the wal-index instead of the VFS shared-memory 
  ** implementation. Take the exclusive lock now, before opening the WAL
  ** file, to make sure this is safe.
  */
  if( pPager->exclusiveMode ){
    rc = pagerExclusiveLock(pPager);
  }

  /* Open the connection to the log file. If this operation fails, 
  ** (e.g. due to malloc() failure), return an error code.
  */
  if( rc==SQLITE_OK ){
    rc = sqlite3WalOpen(pPager->pVfs, 
        pPager->fd, pPager->zWal, pPager->exclusiveMode, &pPager->pWal
    );
  }

  return rc;
}


/*
** The caller must be holding a SHARED lock on the database file to call
** this function.
**
** If the pager passed as the first argument is open on a real database
** file (not a temp file or an in-memory database), and the WAL file

  if( !pPager->tempFile && !pPager->pWal ){
    if( !sqlite3PagerWalSupported(pPager) ) return SQLITE_CANTOPEN;

    /* Close any rollback journal previously open */
    sqlite3OsClose(pPager->jfd);

    /* Open the connection to the log file. If this operation fails, 
    ** (e.g. due to malloc() failure), unlock the database file and 
    ** return an error code.
    */
    rc = pagerOpenWal(pPager);
    rc = sqlite3WalOpen(pPager->pVfs, pPager->fd, pPager->zWal, &pPager->pWal);
    if( rc==SQLITE_OK ){
      pPager->journalMode = PAGER_JOURNALMODE_WAL;
      pPager->eState = PAGER_OPEN;
    }
  }else{
    *pbOpen = 1;
  }

    rc = pagerLockDb(pPager, SHARED_LOCK);
    if( rc==SQLITE_OK ){
      rc = sqlite3OsAccess(
          pPager->pVfs, pPager->zWal, SQLITE_ACCESS_EXISTS, &logexists
      );
    }
    if( rc==SQLITE_OK && logexists ){
      rc = sqlite3WalOpen(pPager->pVfs, pPager->fd,
      rc = pagerOpenWal(pPager);
                          pPager->zWal, &pPager->pWal);
    }
  }
    
  /* Checkpoint and close the log. Because an EXCLUSIVE lock is held on
  ** the database file, the log and log-summary files will be deleted.
  */
  if( rc==SQLITE_OK && pPager->pWal ){
    rc = pagerExclusiveLock(pPager);
    rc = pagerLockDb(pPager, EXCLUSIVE_LOCK);
    if( rc==SQLITE_OK ){
      rc = sqlite3WalClose(pPager->pWal,
          (pPager->noSync ? 0 : pPager->sync_flags), 
          pPager->pageSize, (u8*)pPager->pTmpSpace
                           (pPager->noSync ? 0 : pPager->sync_flags), 
        pPager->pageSize, (u8*)pPager->pTmpSpace
      );
      pPager->pWal = 0;
    }else{
      /* If we cannot get an EXCLUSIVE lock, downgrade the PENDING lock
      ** that we did get back to SHARED. */
      pagerUnlockDb(pPager, SQLITE_LOCK_SHARED);
    }
  }
  return rc;
}

#ifdef SQLITE_HAS_CODEC
/*

  const char *zWalName;      /* Name of WAL file */
  u32 nCkpt;                 /* Checkpoint sequence counter in the wal-header */
#ifdef SQLITE_DEBUG
  u8 lockError;              /* True if a locking error has occurred */
#endif
};

/*
** Candidate values for Wal.exclusiveMode.
*/
#define WAL_NORMAL_MODE     0
#define WAL_EXCLUSIVE_MODE  1     
#define WAL_HEAPMEMORY_MODE 2

/*
** Each page of the wal-index mapping contains a hash-table made up of
** an array of HASHTABLE_NSLOT elements of the following type.
*/
typedef u16 ht_slot;

/*

           sizeof(u32*)*(iPage+1-pWal->nWiData));
    pWal->apWiData = apNew;
    pWal->nWiData = iPage+1;
  }

  /* Request a pointer to the required page from the VFS */
  if( pWal->apWiData[iPage]==0 ){
    if( pWal->exclusiveMode==WAL_HEAPMEMORY_MODE ){
      pWal->apWiData[iPage] = (u32 volatile *)sqlite3MallocZero(WALINDEX_PGSZ);
      if( !pWal->apWiData[iPage] ) rc = SQLITE_NOMEM;
    }else{
      rc = sqlite3OsShmMap(pWal->pDbFd, iPage, WALINDEX_PGSZ, 
          pWal->writeLock, (void volatile **)&pWal->apWiData[iPage]
      );
    rc = sqlite3OsShmMap(pWal->pDbFd, iPage, WALINDEX_PGSZ, 
        pWal->writeLock, (void volatile **)&pWal->apWiData[iPage]
    );
    }
  }

  *ppPage = pWal->apWiData[iPage];
  assert( iPage==0 || *ppPage || rc!=SQLITE_OK );
  return rc;
}

    }while( aData<aEnd );
  }

  aOut[0] = s1;
  aOut[1] = s2;
}

static void walShmBarrier(Wal *pWal){
  if( pWal->exclusiveMode!=WAL_HEAPMEMORY_MODE ){
    sqlite3OsShmBarrier(pWal->pDbFd);
  }
}

/*
** Write the header information in pWal->hdr into the wal-index.
**
** The checksum on pWal->hdr is updated before it is written.
*/
static void walIndexWriteHdr(Wal *pWal){
  volatile WalIndexHdr *aHdr = walIndexHdr(pWal);
  const int nCksum = offsetof(WalIndexHdr, aCksum);

  assert( pWal->writeLock );
  pWal->hdr.isInit = 1;
  pWal->hdr.iVersion = WALINDEX_MAX_VERSION;
  walChecksumBytes(1, (u8*)&pWal->hdr, nCksum, 0, pWal->hdr.aCksum);
  memcpy((void *)&aHdr[1], (void *)&pWal->hdr, sizeof(WalIndexHdr));
  walShmBarrier(pWal);
  sqlite3OsShmBarrier(pWal->pDbFd);
  memcpy((void *)&aHdr[0], (void *)&pWal->hdr, sizeof(WalIndexHdr));
}

/*
** This function encodes a single frame header and writes it to a buffer
** supplied by the caller. A frame-header is made up of a series of 
** 4-byte big-endian integers, as follows:

  return rc;
}

/*
** Close an open wal-index.
*/
static void walIndexClose(Wal *pWal, int isDelete){
  if( pWal->exclusiveMode==WAL_HEAPMEMORY_MODE ){
    int i;
    for(i=0; i<pWal->nWiData; i++){
      sqlite3_free((void *)pWal->apWiData[i]);
      pWal->apWiData[i] = 0;
    }
  }else{
    sqlite3OsShmUnmap(pWal->pDbFd, isDelete);
  sqlite3OsShmUnmap(pWal->pDbFd, isDelete);
  }
}

/* 
** Open a connection to the WAL file zWalName. The database file must 
** already be opened on connection pDbFd. The buffer that zWalName points
** to must remain valid for the lifetime of the returned Wal* handle.
**

** *ppWal is set to point to a new WAL handle. If an error occurs,
** an SQLite error code is returned and *ppWal is left unmodified.
*/
SQLITE_PRIVATE int sqlite3WalOpen(
  sqlite3_vfs *pVfs,              /* vfs module to open wal and wal-index */
  sqlite3_file *pDbFd,            /* The open database file */
  const char *zWalName,           /* Name of the WAL file */
  int bNoShm,                     /* True to run in heap-memory mode */
  Wal **ppWal                     /* OUT: Allocated Wal handle */
){
  int rc;                         /* Return Code */
  Wal *pRet;                      /* Object to allocate and return */
  int flags;                      /* Flags passed to OsOpen() */

  assert( zWalName && zWalName[0] );

  }

  pRet->pVfs = pVfs;
  pRet->pWalFd = (sqlite3_file *)&pRet[1];
  pRet->pDbFd = pDbFd;
  pRet->readLock = -1;
  pRet->zWalName = zWalName;
  pRet->exclusiveMode = (bNoShm ? WAL_HEAPMEMORY_MODE: WAL_NORMAL_MODE);

  /* Open file handle on the write-ahead log file. */
  flags = (SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE|SQLITE_OPEN_WAL);
  rc = sqlite3OsOpen(pVfs, zWalName, pRet->pWalFd, flags, &flags);
  if( rc==SQLITE_OK && flags&SQLITE_OPEN_READONLY ){
    pRet->readOnly = 1;
  }

    ** the database. In this case checkpoint the database and unlink both
    ** the wal and wal-index files.
    **
    ** The EXCLUSIVE lock is not released before returning.
    */
    rc = sqlite3OsLock(pWal->pDbFd, SQLITE_LOCK_EXCLUSIVE);
    if( rc==SQLITE_OK ){
      if( pWal->exclusiveMode==WAL_NORMAL_MODE ){
        pWal->exclusiveMode = WAL_EXCLUSIVE_MODE;
      pWal->exclusiveMode = 1;
      }
      rc = sqlite3WalCheckpoint(pWal, sync_flags, nBuf, zBuf);
      if( rc==SQLITE_OK ){
        isDelete = 1;
      }
    }

    walIndexClose(pWal, isDelete);

  ** There are two copies of the header at the beginning of the wal-index.
  ** When reading, read [0] first then [1].  Writes are in the reverse order.
  ** Memory barriers are used to prevent the compiler or the hardware from
  ** reordering the reads and writes.
  */
  aHdr = walIndexHdr(pWal);
  memcpy(&h1, (void *)&aHdr[0], sizeof(h1));
  walShmBarrier(pWal);
  sqlite3OsShmBarrier(pWal->pDbFd);
  memcpy(&h2, (void *)&aHdr[1], sizeof(h2));

  if( memcmp(&h1, &h2, sizeof(h1))!=0 ){
    return 1;   /* Dirty read */
  }  
  if( h1.isInit==0 ){
    return 1;   /* Malformed header - probably all zeros */

  pInfo = walCkptInfo(pWal);
  if( !useWal && pInfo->nBackfill==pWal->hdr.mxFrame ){
    /* The WAL has been completely backfilled (or it is empty).
    ** and can be safely ignored.
    */
    rc = walLockShared(pWal, WAL_READ_LOCK(0));
    walShmBarrier(pWal);
    sqlite3OsShmBarrier(pWal->pDbFd);
    if( rc==SQLITE_OK ){
      if( memcmp((void *)walIndexHdr(pWal), &pWal->hdr, sizeof(WalIndexHdr)) ){
        /* It is not safe to allow the reader to continue here if frames
        ** may have been appended to the log before READ_LOCK(0) was obtained.
        ** When holding READ_LOCK(0), the reader ignores the entire log file,
        ** which implies that the database file contains a trustworthy
        ** snapshoT. Since holding READ_LOCK(0) prevents a checkpoint from

    **
    ** This does not guarantee that the copy of the wal-index header is up to
    ** date before proceeding. That would not be possible without somehow
    ** blocking writers. It only guarantees that a dangerous checkpoint or 
    ** log-wrap (either of which would require an exclusive lock on
    ** WAL_READ_LOCK(mxI)) has not occurred since the snapshot was valid.
    */
    walShmBarrier(pWal);
    sqlite3OsShmBarrier(pWal->pDbFd);
    if( pInfo->aReadMark[mxI]!=mxReadMark
     || memcmp((void *)walIndexHdr(pWal), &pWal->hdr, sizeof(WalIndexHdr))
    ){
      walUnlockShared(pWal, WAL_READ_LOCK(mxI));
      return WAL_RETRY;
    }else{
      assert( mxReadMark<=pWal->hdr.mxFrame );

** locking_mode=EXCLUSIVE.  This means that the pWal->readLock must
** be released.  Return 1 if the transition is made and 0 if the
** WAL is already in exclusive-locking mode - meaning that this
** routine is a no-op.  The pager must already hold the exclusive lock
** on the main database file before invoking this operation.
**
** If op is negative, then do a dry-run of the op==1 case but do
** not actually change anything. The pager uses this to see if it
** not actually change anything.  The pager uses this to see if it
** should acquire the database exclusive lock prior to invoking
** the op==1 case.
*/
SQLITE_PRIVATE int sqlite3WalExclusiveMode(Wal *pWal, int op){
  int rc;
  assert( pWal->writeLock==0 );
  assert( pWal->exclusiveMode!=WAL_HEAPMEMORY_MODE || op==-1 );

  /* pWal->readLock is usually set, but might be -1 if there was a 
  ** prior error while attempting to acquire are read-lock. This cannot 
  ** happen if the connection is actually in exclusive mode (as no xShmLock
  ** locks are taken in this case). Nor should the pager attempt to
  ** upgrade to exclusive-mode following such an error.
  */

    rc = 1;
  }else{
    rc = pWal->exclusiveMode==0;
  }
  return rc;
}

/* 
** Return true if the argument is non-NULL and the WAL module is using
** heap-memory for the wal-index. Otherwise, if the argument is NULL or the
** WAL module is using shared-memory, return false. 
*/
SQLITE_PRIVATE int sqlite3WalHeapMemory(Wal *pWal){
  return (pWal && pWal->exclusiveMode==WAL_HEAPMEMORY_MODE );
}

#endif /* #ifndef SQLITE_OMIT_WAL */

/************** End of wal.c *************************************************/
/************** Begin file btmutex.c *****************************************/
/*
** 2007 August 27
**

** the rollback journal (which causes the transaction to commit) and
** drop locks.
**
** This will release the write lock on the database file.  If there
** are no active cursors, it also releases the read lock.
*/
SQLITE_PRIVATE int sqlite3BtreeCommitPhaseTwo(Btree *p){
  BtShared *pBt = p->pBt;

  if( p->inTrans==TRANS_NONE ) return SQLITE_OK;
  sqlite3BtreeEnter(p);
  btreeIntegrity(p);

  /* If the handle has a write-transaction open, commit the shared-btrees 
  ** transaction and set the shared state to TRANS_READ.
  */
  if( p->inTrans==TRANS_WRITE ){
    int rc;
    BtShared *pBt = p->pBt;
    assert( pBt->inTransaction==TRANS_WRITE );
    assert( pBt->nTransaction>0 );
    rc = sqlite3PagerCommitPhaseTwo(pBt->pPager);
    if( rc!=SQLITE_OK ){
      sqlite3BtreeLeave(p);
      return rc;
    }

** (stored in BtCursor.aOverflow[]) is allocated and used by function
** accessPayload() (the worker function for sqlite3BtreeData() and
** sqlite3BtreePutData()).
*/
SQLITE_PRIVATE void sqlite3BtreeCacheOverflow(BtCursor *pCur){
  assert( cursorHoldsMutex(pCur) );
  assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
  assert(!pCur->isIncrblobHandle);
  invalidateOverflowCache(pCur);
  assert(!pCur->aOverflow);
  pCur->isIncrblobHandle = 1;
}
#endif

/*
** Set both the "read version" (single byte at byte offset 18) and 
** "write version" (single byte at byte offset 19) fields in the database

    pMem++;

    pMem->flags = MEM_Int;
    pMem->u.i = pOp->p2;                          /* P2 */
    pMem->type = SQLITE_INTEGER;
    pMem++;

    if( p->explain==1 ){
    pMem->flags = MEM_Int;
    pMem->u.i = pOp->p3;                          /* P3 */
    pMem->type = SQLITE_INTEGER;
    pMem++;
      pMem->flags = MEM_Int;
      pMem->u.i = pOp->p3;                          /* P3 */
      pMem->type = SQLITE_INTEGER;
      pMem++;
    }

    if( sqlite3VdbeMemGrow(pMem, 32, 0) ){            /* P4 */
      assert( p->db->mallocFailed );
      return SQLITE_ERROR;
    }
    pMem->flags = MEM_Dyn|MEM_Str|MEM_Term;
    z = displayP4(pOp, pMem->z, 32);

#endif
      {
        pMem->flags = MEM_Null;                       /* Comment */
        pMem->type = SQLITE_NULL;
      }
    }

    p->nResColumn = 8 - 4*(p->explain-1);
    p->nResColumn = 8 - 5*(p->explain-1);
    p->rc = SQLITE_OK;
    rc = SQLITE_ROW;
  }
  return rc;
}
#endif /* SQLITE_OMIT_EXPLAIN */

      if( rc==SQLITE_OK && encoding!=0 ){
        rc = sqlite3VdbeChangeEncoding(pVar, ENC(p->db));
      }
      sqlite3Error(p->db, rc, 0);
      rc = sqlite3ApiExit(p->db, rc);
    }
    sqlite3_mutex_leave(p->db->mutex);
  }else if( xDel!=SQLITE_STATIC && xDel!=SQLITE_TRANSIENT ){
    xDel((void*)zData);
  }
  return rc;
}


/*
** Bind a blob value to an SQL statement variable.

** the first argument to the sqlite3_prepare() that was used to create
** the statement in the first place.
*/
SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt *pStmt){
  return pStmt ? ((Vdbe*)pStmt)->db : 0;
}

/*
** Return true if the prepared statement is guaranteed to not modify the
** database.
*/
SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt){
  return pStmt ? ((Vdbe*)pStmt)->readOnly : 1;
}

/*
** Return a pointer to the next prepared statement after pStmt associated
** with database connection pDb.  If pStmt is NULL, return the first
** prepared statement for the database connection.  Return NULL if there
** are no more.
*/
SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt){

** Valid sqlite3_blob* handles point to Incrblob structures.
*/
typedef struct Incrblob Incrblob;
struct Incrblob {
  int flags;              /* Copy of "flags" passed to sqlite3_blob_open() */
  int nByte;              /* Size of open blob, in bytes */
  int iOffset;            /* Byte offset of blob in cursor data */
  int iCol;               /* Table column this handle is open on */
  BtCursor *pCsr;         /* Cursor pointing at blob row */
  sqlite3_stmt *pStmt;    /* Statement holding cursor open */
  sqlite3 *db;            /* The associated database */
};


/*
** This function is used by both blob_open() and blob_reopen(). It seeks
** the b-tree cursor associated with blob handle p to point to row iRow.
** If successful, SQLITE_OK is returned and subsequent calls to
** sqlite3_blob_read() or sqlite3_blob_write() access the specified row.
**
** If an error occurs, or if the specified row does not exist or does not
** contain a value of type TEXT or BLOB in the column nominated when the
** blob handle was opened, then an error code is returned and *pzErr may
** be set to point to a buffer containing an error message. It is the
** responsibility of the caller to free the error message buffer using
** sqlite3DbFree().
**
** If an error does occur, then the b-tree cursor is closed. All subsequent
** calls to sqlite3_blob_read(), blob_write() or blob_reopen() will 
** immediately return SQLITE_ABORT.
*/
static int blobSeekToRow(Incrblob *p, sqlite3_int64 iRow, char **pzErr){
  int rc;                         /* Error code */
  char *zErr = 0;                 /* Error message */
  Vdbe *v = (Vdbe *)p->pStmt;

  /* Set the value of the SQL statements only variable to integer iRow. 
  ** This is done directly instead of using sqlite3_bind_int64() to avoid 
  ** triggering asserts related to mutexes.
  */
  assert( v->aVar[0].flags&MEM_Int );
  v->aVar[0].u.i = iRow;

  rc = sqlite3_step(p->pStmt);
  if( rc==SQLITE_ROW ){
    u32 type = v->apCsr[0]->aType[p->iCol];
    if( type<12 ){
      zErr = sqlite3MPrintf(p->db, "cannot open value of type %s",
          type==0?"null": type==7?"real": "integer"
      );
      rc = SQLITE_ERROR;
      sqlite3_finalize(p->pStmt);
      p->pStmt = 0;
    }else{
      p->iOffset = v->apCsr[0]->aOffset[p->iCol];
      p->nByte = sqlite3VdbeSerialTypeLen(type);
      p->pCsr =  v->apCsr[0]->pCursor;
      sqlite3BtreeEnterCursor(p->pCsr);
      sqlite3BtreeCacheOverflow(p->pCsr);
      sqlite3BtreeLeaveCursor(p->pCsr);
    }
  }

  if( rc==SQLITE_ROW ){
    rc = SQLITE_OK;
  }else if( p->pStmt ){
    rc = sqlite3_finalize(p->pStmt);
    p->pStmt = 0;
    if( rc==SQLITE_OK ){
      zErr = sqlite3MPrintf(p->db, "no such rowid: %lld", iRow);
      rc = SQLITE_ERROR;
    }else{
      zErr = sqlite3MPrintf(p->db, "%s", sqlite3_errmsg(p->db));
    }
  }

  assert( rc!=SQLITE_OK || zErr==0 );
  assert( rc!=SQLITE_ROW && rc!=SQLITE_DONE );

  *pzErr = zErr;
  return rc;
}

/*
** Open a blob handle.
*/
SQLITE_API int sqlite3_blob_open(
  sqlite3* db,            /* The database connection */
  const char *zDb,        /* The attached database containing the blob */
  const char *zTable,     /* The table containing the blob */

    {OP_TableLock, 0, 0, 0},       /* 2: Acquire a read or write lock */

    /* One of the following two instructions is replaced by an OP_Noop. */
    {OP_OpenRead, 0, 0, 0},        /* 3: Open cursor 0 for reading */
    {OP_OpenWrite, 0, 0, 0},       /* 4: Open cursor 0 for read/write */

    {OP_Variable, 1, 1, 1},        /* 5: Push the rowid to the stack */
    {OP_NotExists, 0, 10, 1},      /* 6: Seek the cursor */
    {OP_NotExists, 0, 9, 1},       /* 6: Seek the cursor */
    {OP_Column, 0, 0, 1},          /* 7  */
    {OP_ResultRow, 1, 0, 0},       /* 8  */
    {OP_Goto, 0, 5, 0},            /* 9  */
    {OP_Close, 0, 0, 0},           /* 10 */
    {OP_Halt, 0, 0, 0},            /* 11 */
    {OP_Close, 0, 0, 0},           /* 9  */
    {OP_Halt, 0, 0, 0},            /* 10 */
  };

  Vdbe *v = 0;
  int rc = SQLITE_OK;
  char *zErr = 0;
  Table *pTab;
  Parse *pParse = 0;
  Parse *pParse;
  Incrblob *pBlob = 0;

  flags = !!flags;                /* flags = (flags ? 1 : 0); */
  *ppBlob = 0;

  sqlite3_mutex_enter(db->mutex);

  pBlob = (Incrblob *)sqlite3DbMallocZero(db, sizeof(Incrblob));
  if( !pBlob ) goto blob_open_out;
  pParse = sqlite3StackAllocRaw(db, sizeof(*pParse));
  if( pParse==0 ){
    rc = SQLITE_NOMEM;
  if( !pParse ) goto blob_open_out;

    goto blob_open_out;
  }
  do {
    memset(pParse, 0, sizeof(Parse));
    pParse->db = db;
    sqlite3DbFree(db, zErr);
    zErr = 0;

    sqlite3BtreeEnterAll(db);
    pTab = sqlite3LocateTable(pParse, 0, zTable, zDb);
    if( pTab && IsVirtual(pTab) ){
      pTab = 0;
      sqlite3ErrorMsg(pParse, "cannot open virtual table: %s", zTable);
    }

      }
      rc = SQLITE_ERROR;
      sqlite3BtreeLeaveAll(db);
      goto blob_open_out;
    }

    /* Now search pTab for the exact column. */
    for(iCol=0; iCol<pTab->nCol; iCol++) {
    for(iCol=0; iCol < pTab->nCol; iCol++) {
      if( sqlite3StrICmp(pTab->aCol[iCol].zName, zColumn)==0 ){
        break;
      }
    }
    if( iCol==pTab->nCol ){
      sqlite3DbFree(db, zErr);
      zErr = sqlite3MPrintf(db, "no such column: \"%s\"", zColumn);

        zErr = sqlite3MPrintf(db, "cannot open %s column for writing", zFault);
        rc = SQLITE_ERROR;
        sqlite3BtreeLeaveAll(db);
        goto blob_open_out;
      }
    }

    pBlob->pStmt = (sqlite3_stmt *)sqlite3VdbeCreate(db);
    v = sqlite3VdbeCreate(db);
    assert( pBlob->pStmt || db->mallocFailed );
    if( pBlob->pStmt ){
    if( v ){
      Vdbe *v = (Vdbe *)pBlob->pStmt;
      int iDb = sqlite3SchemaToIndex(db, pTab->pSchema);

      sqlite3VdbeAddOpList(v, sizeof(openBlob)/sizeof(VdbeOpList), openBlob);

      flags = !!flags;                 /* flags = (flags ? 1 : 0); */

      /* Configure the OP_Transaction */
      sqlite3VdbeChangeP1(v, 0, iDb);
      sqlite3VdbeChangeP2(v, 0, flags);

      /* Configure the OP_VerifyCookie */
      sqlite3VdbeChangeP1(v, 1, iDb);

      sqlite3VdbeChangeP4(v, 3+flags, SQLITE_INT_TO_PTR(pTab->nCol+1),P4_INT32);
      sqlite3VdbeChangeP2(v, 7, pTab->nCol);
      if( !db->mallocFailed ){
        sqlite3VdbeMakeReady(v, 1, 1, 1, 0, 0, 0);
      }
    }
   
    pBlob->flags = flags;
    pBlob->iCol = iCol;
    pBlob->db = db;
    sqlite3BtreeLeaveAll(db);
    if( db->mallocFailed ){
      goto blob_open_out;
    }

    sqlite3_bind_int64(pBlob->pStmt, 1, iRow);
    rc = blobSeekToRow(pBlob, iRow, &zErr);
  } while( (++nAttempt)<5 && rc==SQLITE_SCHEMA );
    sqlite3_bind_int64((sqlite3_stmt *)v, 1, iRow);
    rc = sqlite3_step((sqlite3_stmt *)v);
    if( rc!=SQLITE_ROW ){
      nAttempt++;
      rc = sqlite3_finalize((sqlite3_stmt *)v);
      sqlite3DbFree(db, zErr);
      zErr = sqlite3MPrintf(db, sqlite3_errmsg(db));
      v = 0;
    }
  } while( nAttempt<5 && rc==SQLITE_SCHEMA );

  if( rc==SQLITE_ROW ){
    /* The row-record has been opened successfully. Check that the
    ** column in question contains text or a blob. If it contains
    ** text, it is up to the caller to get the encoding right.
    */
    Incrblob *pBlob;
    u32 type = v->apCsr[0]->aType[iCol];

    if( type<12 ){
      sqlite3DbFree(db, zErr);
      zErr = sqlite3MPrintf(db, "cannot open value of type %s",
          type==0?"null": type==7?"real": "integer"
      );
      rc = SQLITE_ERROR;
blob_open_out:
  if( rc==SQLITE_OK && db->mallocFailed==0 ){
      goto blob_open_out;
    }
    pBlob = (Incrblob *)sqlite3DbMallocZero(db, sizeof(Incrblob));
    if( db->mallocFailed ){
      sqlite3DbFree(db, pBlob);
      goto blob_open_out;
    }
    pBlob->flags = flags;
    pBlob->pCsr =  v->apCsr[0]->pCursor;
    sqlite3BtreeEnterCursor(pBlob->pCsr);
    sqlite3BtreeCacheOverflow(pBlob->pCsr);
    sqlite3BtreeLeaveCursor(pBlob->pCsr);
    pBlob->pStmt = (sqlite3_stmt *)v;
    pBlob->iOffset = v->apCsr[0]->aOffset[iCol];
    pBlob->nByte = sqlite3VdbeSerialTypeLen(type);
    pBlob->db = db;
    *ppBlob = (sqlite3_blob *)pBlob;
    rc = SQLITE_OK;
  }else{
  }else if( rc==SQLITE_OK ){
    if( pBlob && pBlob->pStmt ) sqlite3VdbeFinalize((Vdbe *)pBlob->pStmt);
    sqlite3DbFree(db, pBlob);
    sqlite3DbFree(db, zErr);
    zErr = sqlite3MPrintf(db, "no such rowid: %lld", iRow);
    rc = SQLITE_ERROR;
  }

blob_open_out:
  if( v && (rc!=SQLITE_OK || db->mallocFailed) ){
    sqlite3VdbeFinalize(v);
  }
  sqlite3Error(db, rc, (zErr ? "%s" : 0), zErr);
  sqlite3Error(db, rc, zErr);
  sqlite3DbFree(db, zErr);
  sqlite3StackFree(db, pParse);
  rc = sqlite3ApiExit(db, rc);
  sqlite3_mutex_leave(db->mutex);
  return rc;
}

  sqlite3_mutex_enter(db->mutex);
  v = (Vdbe*)p->pStmt;

  if( n<0 || iOffset<0 || (iOffset+n)>p->nByte ){
    /* Request is out of range. Return a transient error. */
    rc = SQLITE_ERROR;
    sqlite3Error(db, SQLITE_ERROR, 0);
  }else if( v==0 ){
  } else if( v==0 ){
    /* If there is no statement handle, then the blob-handle has
    ** already been invalidated. Return SQLITE_ABORT in this case.
    */
    rc = SQLITE_ABORT;
  }else{
    /* Call either BtreeData() or BtreePutData(). If SQLITE_ABORT is
    ** returned, clean-up the statement handle.

** so no mutex is required for access.
*/
SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *pBlob){
  Incrblob *p = (Incrblob *)pBlob;
  return p ? p->nByte : 0;
}

/*
** Move an existing blob handle to point to a different row of the same
** database table.
**
** If an error occurs, or if the specified row does not exist or does not
** contain a blob or text value, then an error code is returned and the
** database handle error code and message set. If this happens, then all 
** subsequent calls to sqlite3_blob_xxx() functions (except blob_close()) 
** immediately return SQLITE_ABORT.
*/
SQLITE_API int sqlite3_blob_reopen(sqlite3_blob *pBlob, sqlite3_int64 iRow){
  int rc;
  Incrblob *p = (Incrblob *)pBlob;
  sqlite3 *db;

  if( p==0 ) return SQLITE_MISUSE_BKPT;
  db = p->db;
  sqlite3_mutex_enter(db->mutex);

  if( p->pStmt==0 ){
    /* If there is no statement handle, then the blob-handle has
    ** already been invalidated. Return SQLITE_ABORT in this case.
    */
    rc = SQLITE_ABORT;
  }else{
    char *zErr;
    rc = blobSeekToRow(p, iRow, &zErr);
    if( rc!=SQLITE_OK ){
      sqlite3Error(db, rc, (zErr ? "%s" : 0), zErr);
      sqlite3DbFree(db, zErr);
    }
    assert( rc!=SQLITE_SCHEMA );
  }

  rc = sqlite3ApiExit(db, rc);
  sqlite3_mutex_leave(db->mutex);
  return rc;
}

#endif /* #ifndef SQLITE_OMIT_INCRBLOB */

/************** End of vdbeblob.c ********************************************/
/************** Begin file journal.c *****************************************/
/*
** 2007 August 22
**

  int op,                 /* Expression opcode */
  Expr *pLeft,            /* Left operand */
  Expr *pRight,           /* Right operand */
  const Token *pToken     /* Argument token */
){
  Expr *p = sqlite3ExprAlloc(pParse->db, op, pToken, 1);
  sqlite3ExprAttachSubtrees(pParse->db, p, pLeft, pRight);
  if( p ) {
    sqlite3ExprCheckHeight(pParse, p->nHeight);
  }
  return p;
}

/*
** Join two expressions using an AND operator.  If either expression is
** NULL, then just return the other expression.
*/

  if( !ExprHasAnyProperty(pExpr, EP_VarSelect) && !pParse->pTriggerTab ){
    int mem = ++pParse->nMem;
    sqlite3VdbeAddOp1(v, OP_If, mem);
    testAddr = sqlite3VdbeAddOp2(v, OP_Integer, 1, mem);
    assert( testAddr>0 || pParse->db->mallocFailed );
  }

#ifndef SQLITE_OMIT_EXPLAIN
  if( pParse->explain==2 ){
    char *zMsg = sqlite3MPrintf(
        pParse->db, "EXECUTE %s%s SUBQUERY %d", testAddr?"":"CORRELATED ",
        pExpr->op==TK_IN?"LIST":"SCALAR", pParse->iNextSelectId
    );
    sqlite3VdbeAddOp4(v, OP_Explain, pParse->iSelectId, 0, 0, zMsg, P4_DYNAMIC);
  }
#endif

  switch( pExpr->op ){
    case TK_IN: {
      char affinity;              /* Affinity of the LHS of the IN */
      KeyInfo keyInfo;            /* Keyinfo for the generated table */
      int addr;                   /* Address of OP_OpenEphemeral instruction */
      Expr *pLeft = pExpr->pLeft; /* the LHS of the IN operator */

  void (*randomness)(int,void*);
  sqlite3 *(*context_db_handle)(sqlite3_context*);
  int (*extended_result_codes)(sqlite3*,int);
  int (*limit)(sqlite3*,int,int);
  sqlite3_stmt *(*next_stmt)(sqlite3*,sqlite3_stmt*);
  const char *(*sql)(sqlite3_stmt*);
  int (*status)(int,int*,int*,int);
  int (*backup_finish)(sqlite3_backup*);
  sqlite3_backup *(*backup_init)(sqlite3*,const char*,sqlite3*,const char*);
  int (*backup_pagecount)(sqlite3_backup*);
  int (*backup_remaining)(sqlite3_backup*);
  int (*backup_step)(sqlite3_backup*,int);
  const char *(*compileoption_get)(int);
  int (*compileoption_used)(const char*);
  int (*create_function_v2)(sqlite3*,const char*,int,int,void*,void (*xFunc)(sqlite3_context*,int,sqlite3_value**),void (*xStep)(sqlite3_context*,int,sqlite3_value**),void (*xFinal)(sqlite3_context*),void(*xDestroy)(void*));
  int (*db_config)(sqlite3*,int,...);
  sqlite3_mutex *(*db_mutex)(sqlite3*);
  int (*db_status)(sqlite3*,int,int*,int*,int);
  int (*extended_errcode)(sqlite3*);
  void (*log)(int,const char*,...);
  sqlite3_int64 (*soft_heap_limit64)(sqlite3_int64);
  const char *(*sourceid)(void);
  int (*stmt_status)(sqlite3_stmt*,int,int);
  int (*strnicmp)(const char*,const char*,int);
  int (*unlock_notify)(sqlite3*,void(*)(void**,int),void*);
  int (*wal_autocheckpoint)(sqlite3*,int);
  int (*wal_checkpoint)(sqlite3*,const char*);
  void *(*wal_hook)(sqlite3*,int(*)(void*,sqlite3*,const char*,int),void*);
};

/*
** The following macros redefine the API routines so that they are
** redirected throught the global sqlite3_api structure.
**
** This header file is also used by the loadext.c source file

#define sqlite3_randomness             sqlite3_api->randomness
#define sqlite3_context_db_handle      sqlite3_api->context_db_handle
#define sqlite3_extended_result_codes  sqlite3_api->extended_result_codes
#define sqlite3_limit                  sqlite3_api->limit
#define sqlite3_next_stmt              sqlite3_api->next_stmt
#define sqlite3_sql                    sqlite3_api->sql
#define sqlite3_status                 sqlite3_api->status
#define sqlite3_backup_finish          sqlite3_api->backup_finish
#define sqlite3_backup_init            sqlite3_api->backup_init
#define sqlite3_backup_pagecount       sqlite3_api->backup_pagecount
#define sqlite3_backup_remaining       sqlite3_api->backup_remaining
#define sqlite3_backup_step            sqlite3_api->backup_step
#define sqlite3_compileoption_get      sqlite3_api->compileoption_get
#define sqlite3_compileoption_used     sqlite3_api->compileoption_used
#define sqlite3_create_function_v2     sqlite3_api->create_function_v2
#define sqlite3_db_config              sqlite3_api->db_config
#define sqlite3_db_mutex               sqlite3_api->db_mutex
#define sqlite3_db_status              sqlite3_api->db_status
#define sqlite3_extended_errcode       sqlite3_api->extended_errcode
#define sqlite3_log                    sqlite3_api->log
#define sqlite3_soft_heap_limit64      sqlite3_api->soft_heap_limit64
#define sqlite3_sourceid               sqlite3_api->sourceid
#define sqlite3_stmt_status            sqlite3_api->stmt_status
#define sqlite3_strnicmp               sqlite3_api->strnicmp
#define sqlite3_unlock_notify          sqlite3_api->unlock_notify
#define sqlite3_wal_autocheckpoint     sqlite3_api->wal_autocheckpoint
#define sqlite3_wal_checkpoint         sqlite3_api->wal_checkpoint
#define sqlite3_wal_hook               sqlite3_api->wal_hook
#endif /* SQLITE_CORE */

#define SQLITE_EXTENSION_INIT1     const sqlite3_api_routines *sqlite3_api = 0;
#define SQLITE_EXTENSION_INIT2(v)  sqlite3_api = v;

#endif /* _SQLITE3EXT_H_ */

  ** Added for 3.6.0
  */
  sqlite3_extended_result_codes,
  sqlite3_limit,
  sqlite3_next_stmt,
  sqlite3_sql,
  sqlite3_status,

  /*
  ** Added for 3.7.4
  */
  sqlite3_backup_finish,
  sqlite3_backup_init,
  sqlite3_backup_pagecount,
  sqlite3_backup_remaining,
  sqlite3_backup_step,
#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
  sqlite3_compileoption_get,
  sqlite3_compileoption_used,
#else
  0,
  0,
#endif
  sqlite3_create_function_v2,
  sqlite3_db_config,
  sqlite3_db_mutex,
  sqlite3_db_status,
  sqlite3_extended_errcode,
  sqlite3_log,
  sqlite3_soft_heap_limit64,
  sqlite3_sourceid,
  sqlite3_stmt_status,
  sqlite3_strnicmp,
#ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
  sqlite3_unlock_notify,
#else
  0,
#endif
#ifndef SQLITE_OMIT_WAL
  sqlite3_wal_autocheckpoint,
  sqlite3_wal_checkpoint,
  sqlite3_wal_hook,
#else
  0,
  0,
  0,
#endif
};

/*
** Attempt to load an SQLite extension library contained in the file
** zFile.  The entry point is zProc.  zProc may be 0 in which case a
** default entry point name (sqlite3_extension_init) is used.  Use
** of the default name is recommended.

  }
  rc = pParse->rc;

#ifndef SQLITE_OMIT_EXPLAIN
  if( rc==SQLITE_OK && pParse->pVdbe && pParse->explain ){
    static const char * const azColName[] = {
       "addr", "opcode", "p1", "p2", "p3", "p4", "p5", "comment",
       "selectid", "order", "from", "detail"
       "order", "from", "detail"
    };
    int iFirst, mx;
    if( pParse->explain==2 ){
      sqlite3VdbeSetNumCols(pParse->pVdbe, 4);
      sqlite3VdbeSetNumCols(pParse->pVdbe, 3);
      iFirst = 8;
      mx = 12;
      mx = 11;
    }else{
      sqlite3VdbeSetNumCols(pParse->pVdbe, 8);
      iFirst = 0;
      mx = 8;
    }
    for(i=iFirst; i<mx; i++){
      sqlite3VdbeSetColName(pParse->pVdbe, i-iFirst, COLNAME_NAME,

      pInfo->aColl[i] = pColl;
      pInfo->aSortOrder[i] = pItem->sortOrder;
    }
  }
  return pInfo;
}

#ifndef SQLITE_OMIT_COMPOUND_SELECT
/*
** Name of the connection operator, used for error messages.
*/
static const char *selectOpName(int id){
  char *z;
  switch( id ){
    case TK_ALL:       z = "UNION ALL";   break;
    case TK_INTERSECT: z = "INTERSECT";   break;
    case TK_EXCEPT:    z = "EXCEPT";      break;
    default:           z = "UNION";       break;
  }
  return z;
}
#endif /* SQLITE_OMIT_COMPOUND_SELECT */

#ifndef SQLITE_OMIT_EXPLAIN
/*
** Unless an "EXPLAIN QUERY PLAN" command is being processed, this function
** is a no-op. Otherwise, it adds a single row of output to the EQP result,
** where the caption is of the form:
**
**   "USE TEMP B-TREE FOR xxx"
**
** where xxx is one of "DISTINCT", "ORDER BY" or "GROUP BY". Exactly which
** is determined by the zUsage argument.
*/
static void explainTempTable(Parse *pParse, const char *zUsage){
  if( pParse->explain==2 ){
    Vdbe *v = pParse->pVdbe;
    char *zMsg = sqlite3MPrintf(pParse->db, "USE TEMP B-TREE FOR %s", zUsage);
    sqlite3VdbeAddOp4(v, OP_Explain, pParse->iSelectId, 0, 0, zMsg, P4_DYNAMIC);
  }
}

/*
** Unless an "EXPLAIN QUERY PLAN" command is being processed, this function
** is a no-op. Otherwise, it adds a single row of output to the EQP result,
** where the caption is of one of the two forms:
**
**   "COMPOSITE SUBQUERIES iSub1 and iSub2 (op)"
**   "COMPOSITE SUBQUERIES iSub1 and iSub2 USING TEMP B-TREE (op)"
**
** where iSub1 and iSub2 are the integers passed as the corresponding
** function parameters, and op is the text representation of the parameter
** of the same name. The parameter "op" must be one of TK_UNION, TK_EXCEPT,
** TK_INTERSECT or TK_ALL. The first form is used if argument bUseTmp is 
** false, or the second form if it is true.
*/
static void explainComposite(
  Parse *pParse,                  /* Parse context */
  int op,                         /* One of TK_UNION, TK_EXCEPT etc. */
  int iSub1,                      /* Subquery id 1 */
  int iSub2,                      /* Subquery id 2 */
  int bUseTmp                     /* True if a temp table was used */
){
  assert( op==TK_UNION || op==TK_EXCEPT || op==TK_INTERSECT || op==TK_ALL );
  if( pParse->explain==2 ){
    Vdbe *v = pParse->pVdbe;
    char *zMsg = sqlite3MPrintf(
        pParse->db, "COMPOUND SUBQUERIES %d AND %d %s(%s)", iSub1, iSub2,
        bUseTmp?"USING TEMP B-TREE ":"", selectOpName(op)
    );
    sqlite3VdbeAddOp4(v, OP_Explain, pParse->iSelectId, 0, 0, zMsg, P4_DYNAMIC);
  }
}

/*
** Assign expression b to lvalue a. A second, no-op, version of this macro
** is provided when SQLITE_OMIT_EXPLAIN is defined. This allows the code
** in sqlite3Select() to assign values to structure member variables that
** only exist if SQLITE_OMIT_EXPLAIN is not defined without polluting the
** code with #ifndef directives.
*/
# define explainSetInteger(a, b) a = b

#else
/* No-op versions of the explainXXX() functions and macros. */
# define explainTempTable(y,z)
# define explainComposite(v,w,x,y,z)
# define explainSetInteger(y,z)
#endif

/*
** If the inner loop was generated using a non-null pOrderBy argument,
** then the results were placed in a sorter.  After the loop is terminated
** we need to run the sorter and output the results.  The following
** routine generates the code needed to do that.
*/

      sqlite3VdbeSetColName(v, i, COLNAME_NAME, 
          sqlite3DbStrDup(db, pEList->a[i].zSpan), SQLITE_DYNAMIC);
    }
  }
  generateColumnTypes(pParse, pTabList, pEList);
}

#ifndef SQLITE_OMIT_COMPOUND_SELECT
/*
** Name of the connection operator, used for error messages.
*/
static const char *selectOpName(int id){
  char *z;
  switch( id ){
    case TK_ALL:       z = "UNION ALL";   break;
    case TK_INTERSECT: z = "INTERSECT";   break;
    case TK_EXCEPT:    z = "EXCEPT";      break;
    default:           z = "UNION";       break;
  }
  return z;
}
#endif /* SQLITE_OMIT_COMPOUND_SELECT */

/*
** Given a an expression list (which is really the list of expressions
** that form the result set of a SELECT statement) compute appropriate
** column names for a table that would hold the expression list.
**
** All column names will be unique.
**

    return 0;
  }
  /* The sqlite3ResultSetOfSelect() is only used n contexts where lookaside
  ** is disabled */
  assert( db->lookaside.bEnabled==0 );
  pTab->nRef = 1;
  pTab->zName = 0;
  pTab->nRowEst = 1000000;
  selectColumnsFromExprList(pParse, pSelect->pEList, &pTab->nCol, &pTab->aCol);
  selectAddColumnTypeAndCollation(pParse, pTab->nCol, pTab->aCol, pSelect);
  pTab->iPKey = -1;
  if( db->mallocFailed ){
    sqlite3DeleteTable(db, pTab);
    return 0;
  }

    v = sqlite3GetVdbe(pParse);
    if( NEVER(v==0) ) return;  /* VDBE should have already been allocated */
    if( sqlite3ExprIsInteger(p->pLimit, &n) ){
      sqlite3VdbeAddOp2(v, OP_Integer, n, iLimit);
      VdbeComment((v, "LIMIT counter"));
      if( n==0 ){
        sqlite3VdbeAddOp2(v, OP_Goto, 0, iBreak);
      }else{
        if( p->nSelectRow > (double)n ) p->nSelectRow = (double)n;
      }
    }else{
      sqlite3ExprCode(pParse, p->pLimit, iLimit);
      sqlite3VdbeAddOp1(v, OP_MustBeInt, iLimit);
      VdbeComment((v, "LIMIT counter"));
      sqlite3VdbeAddOp2(v, OP_IfZero, iLimit, iBreak);
    }

){
  int rc = SQLITE_OK;   /* Success code from a subroutine */
  Select *pPrior;       /* Another SELECT immediately to our left */
  Vdbe *v;              /* Generate code to this VDBE */
  SelectDest dest;      /* Alternative data destination */
  Select *pDelete = 0;  /* Chain of simple selects to delete */
  sqlite3 *db;          /* Database connection */
#ifndef SQLITE_OMIT_EXPLAIN
  int iSub1;            /* EQP id of left-hand query */
  int iSub2;            /* EQP id of right-hand query */
#endif

  /* Make sure there is no ORDER BY or LIMIT clause on prior SELECTs.  Only
  ** the last (right-most) SELECT in the series may have an ORDER BY or LIMIT.
  */
  assert( p && p->pPrior );  /* Calling function guarantees this much */
  db = pParse->db;
  pPrior = p->pPrior;

  }

  /* Generate code for the left and right SELECT statements.
  */
  switch( p->op ){
    case TK_ALL: {
      int addr = 0;
      int nLimit;
      assert( !pPrior->pLimit );
      pPrior->pLimit = p->pLimit;
      pPrior->pOffset = p->pOffset;
      explainSetInteger(iSub1, pParse->iNextSelectId);
      rc = sqlite3Select(pParse, pPrior, &dest);
      p->pLimit = 0;
      p->pOffset = 0;
      if( rc ){
        goto multi_select_end;
      }
      p->pPrior = 0;
      p->iLimit = pPrior->iLimit;
      p->iOffset = pPrior->iOffset;
      if( p->iLimit ){
        addr = sqlite3VdbeAddOp1(v, OP_IfZero, p->iLimit);
        VdbeComment((v, "Jump ahead if LIMIT reached"));
      }
      explainSetInteger(iSub2, pParse->iNextSelectId);
      rc = sqlite3Select(pParse, p, &dest);
      testcase( rc!=SQLITE_OK );
      pDelete = p->pPrior;
      p->pPrior = pPrior;
      p->nSelectRow += pPrior->nSelectRow;
      if( pPrior->pLimit
       && sqlite3ExprIsInteger(pPrior->pLimit, &nLimit)
       && p->nSelectRow > (double)nLimit 
      ){
        p->nSelectRow = (double)nLimit;
      }
      if( addr ){
        sqlite3VdbeJumpHere(v, addr);
      }
      break;
    }
    case TK_EXCEPT:
    case TK_UNION: {

        assert( p->pEList );
      }

      /* Code the SELECT statements to our left
      */
      assert( !pPrior->pOrderBy );
      sqlite3SelectDestInit(&uniondest, priorOp, unionTab);
      explainSetInteger(iSub1, pParse->iNextSelectId);
      rc = sqlite3Select(pParse, pPrior, &uniondest);
      if( rc ){
        goto multi_select_end;
      }

      /* Code the current SELECT statement
      */
      if( p->op==TK_EXCEPT ){
        op = SRT_Except;
      }else{
        assert( p->op==TK_UNION );
        op = SRT_Union;
      }
      p->pPrior = 0;
      pLimit = p->pLimit;
      p->pLimit = 0;
      pOffset = p->pOffset;
      p->pOffset = 0;
      uniondest.eDest = op;
      explainSetInteger(iSub2, pParse->iNextSelectId);
      rc = sqlite3Select(pParse, p, &uniondest);
      testcase( rc!=SQLITE_OK );
      /* Query flattening in sqlite3Select() might refill p->pOrderBy.
      ** Be sure to delete p->pOrderBy, therefore, to avoid a memory leak. */
      sqlite3ExprListDelete(db, p->pOrderBy);
      pDelete = p->pPrior;
      p->pPrior = pPrior;
      p->pOrderBy = 0;
      if( p->op==TK_UNION ) p->nSelectRow += pPrior->nSelectRow;
      sqlite3ExprDelete(db, p->pLimit);
      p->pLimit = pLimit;
      p->pOffset = pOffset;
      p->iLimit = 0;
      p->iOffset = 0;

      /* Convert the data in the temporary table into whatever form

      p->addrOpenEphm[0] = addr;
      p->pRightmost->selFlags |= SF_UsesEphemeral;
      assert( p->pEList );

      /* Code the SELECTs to our left into temporary table "tab1".
      */
      sqlite3SelectDestInit(&intersectdest, SRT_Union, tab1);
      explainSetInteger(iSub1, pParse->iNextSelectId);
      rc = sqlite3Select(pParse, pPrior, &intersectdest);
      if( rc ){
        goto multi_select_end;
      }

      /* Code the current SELECT into temporary table "tab2"
      */
      addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, tab2, 0);
      assert( p->addrOpenEphm[1] == -1 );
      p->addrOpenEphm[1] = addr;
      p->pPrior = 0;
      pLimit = p->pLimit;
      p->pLimit = 0;
      pOffset = p->pOffset;
      p->pOffset = 0;
      intersectdest.iParm = tab2;
      explainSetInteger(iSub2, pParse->iNextSelectId);
      rc = sqlite3Select(pParse, p, &intersectdest);
      testcase( rc!=SQLITE_OK );
      pDelete = p->pPrior;
      p->pPrior = pPrior;
      if( p->nSelectRow>pPrior->nSelectRow ) p->nSelectRow = pPrior->nSelectRow;
      sqlite3ExprDelete(db, p->pLimit);
      p->pLimit = pLimit;
      p->pOffset = pOffset;

      /* Generate code to take the intersection of the two temporary
      ** tables.
      */

      sqlite3VdbeResolveLabel(v, iBreak);
      sqlite3VdbeAddOp2(v, OP_Close, tab2, 0);
      sqlite3VdbeAddOp2(v, OP_Close, tab1, 0);
      break;
    }
  }

  explainComposite(pParse, p->op, iSub1, iSub2, p->op!=TK_ALL);

  /* Compute collating sequences used by 
  ** temporary tables needed to implement the compound select.
  ** Attach the KeyInfo structure to all temporary tables.
  **
  ** This section is run by the right-most SELECT statement only.
  ** SELECT statements to the left always skip this part.  The right-most
  ** SELECT might also skip this part if it has no ORDER BY clause and

  int op;               /* One of TK_ALL, TK_UNION, TK_EXCEPT, TK_INTERSECT */
  KeyInfo *pKeyDup = 0; /* Comparison information for duplicate removal */
  KeyInfo *pKeyMerge;   /* Comparison information for merging rows */
  sqlite3 *db;          /* Database connection */
  ExprList *pOrderBy;   /* The ORDER BY clause */
  int nOrderBy;         /* Number of terms in the ORDER BY clause */
  int *aPermute;        /* Mapping from ORDER BY terms to result set columns */
#ifndef SQLITE_OMIT_EXPLAIN
  int iSub1;            /* EQP id of left-hand query */
  int iSub2;            /* EQP id of right-hand query */
#endif

  assert( p->pOrderBy!=0 );
  assert( pKeyDup==0 ); /* "Managed" code needs this.  Ticket #3382. */
  db = pParse->db;
  v = pParse->pVdbe;
  assert( v!=0 );       /* Already thrown the error if VDBE alloc failed */
  labelEnd = sqlite3VdbeMakeLabel(v);

  /* Generate a coroutine to evaluate the SELECT statement to the
  ** left of the compound operator - the "A" select.
  */
  VdbeNoopComment((v, "Begin coroutine for left SELECT"));
  pPrior->iLimit = regLimitA;
  explainSetInteger(iSub1, pParse->iNextSelectId);
  sqlite3Select(pParse, pPrior, &destA);
  sqlite3VdbeAddOp2(v, OP_Integer, 1, regEofA);
  sqlite3VdbeAddOp1(v, OP_Yield, regAddrA);
  VdbeNoopComment((v, "End coroutine for left SELECT"));

  /* Generate a coroutine to evaluate the SELECT statement on 
  ** the right - the "B" select
  */
  addrSelectB = sqlite3VdbeCurrentAddr(v);
  VdbeNoopComment((v, "Begin coroutine for right SELECT"));
  savedLimit = p->iLimit;
  savedOffset = p->iOffset;
  p->iLimit = regLimitB;
  p->iOffset = 0;  
  explainSetInteger(iSub2, pParse->iNextSelectId);
  sqlite3Select(pParse, p, &destB);
  p->iLimit = savedLimit;
  p->iOffset = savedOffset;
  sqlite3VdbeAddOp2(v, OP_Integer, 1, regEofB);
  sqlite3VdbeAddOp1(v, OP_Yield, regAddrB);
  VdbeNoopComment((v, "End coroutine for right SELECT"));

  if( op==TK_EXCEPT || op==TK_INTERSECT ){
    addrEofA = sqlite3VdbeAddOp2(v, OP_Goto, 0, labelEnd);
  }else{  
    addrEofA = sqlite3VdbeAddOp2(v, OP_If, regEofB, labelEnd);
    sqlite3VdbeAddOp2(v, OP_Gosub, regOutB, addrOutB);
    sqlite3VdbeAddOp1(v, OP_Yield, regAddrB);
    sqlite3VdbeAddOp2(v, OP_Goto, 0, addrEofA);
    p->nSelectRow += pPrior->nSelectRow;
  }

  /* Generate a subroutine to run when the results from select B
  ** are exhausted and only data in select A remains.
  */
  if( op==TK_INTERSECT ){
    addrEofB = addrEofA;
    if( p->nSelectRow > pPrior->nSelectRow ) p->nSelectRow = pPrior->nSelectRow;
  }else{  
    VdbeNoopComment((v, "eof-B subroutine"));
    addrEofB = sqlite3VdbeAddOp2(v, OP_If, regEofA, labelEnd);
    sqlite3VdbeAddOp2(v, OP_Gosub, regOutA, addrOutA);
    sqlite3VdbeAddOp1(v, OP_Yield, regAddrA);
    sqlite3VdbeAddOp2(v, OP_Goto, 0, addrEofB);
  }

  if( p->pPrior ){
    sqlite3SelectDelete(db, p->pPrior);
  }
  p->pPrior = pPrior;

  /*** TBD:  Insert subroutine calls to close cursors on incomplete
  **** subqueries ****/
  explainComposite(pParse, p->op, iSub1, iSub2, 0);
  return SQLITE_OK;
}
#endif

#if !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW)
/* Forward Declarations */
static void substExprList(sqlite3*, ExprList*, int, ExprList*);

      pFrom->pTab = pTab = sqlite3DbMallocZero(db, sizeof(Table));
      if( pTab==0 ) return WRC_Abort;
      pTab->nRef = 1;
      pTab->zName = sqlite3MPrintf(db, "sqlite_subquery_%p_", (void*)pTab);
      while( pSel->pPrior ){ pSel = pSel->pPrior; }
      selectColumnsFromExprList(pParse, pSel->pEList, &pTab->nCol, &pTab->aCol);
      pTab->iPKey = -1;
      pTab->nRowEst = 1000000;
      pTab->tabFlags |= TF_Ephemeral;
#endif
    }else{
      /* An ordinary table or view name in the FROM clause */
      assert( pFrom->pTab==0 );
      pFrom->pTab = pTab = 
        sqlite3LocateTable(pParse,0,pFrom->zName,pFrom->zDatabase);

  int distinct;          /* Table to use for the distinct set */
  int rc = 1;            /* Value to return from this function */
  int addrSortIndex;     /* Address of an OP_OpenEphemeral instruction */
  AggInfo sAggInfo;      /* Information used by aggregate queries */
  int iEnd;              /* Address of the end of the query */
  sqlite3 *db;           /* The database connection */

#ifndef SQLITE_OMIT_EXPLAIN
  int iRestoreSelectId = pParse->iSelectId;
  pParse->iSelectId = pParse->iNextSelectId++;
#endif

  db = pParse->db;
  if( p==0 || db->mallocFailed || pParse->nErr ){
    return 1;
  }
  if( sqlite3AuthCheck(pParse, SQLITE_SELECT, 0, 0, 0) ) return 1;
  memset(&sAggInfo, 0, sizeof(sAggInfo));

        isAgg = 1;
        p->selFlags |= SF_Aggregate;
      }
      i = -1;
    }else{
      sqlite3SelectDestInit(&dest, SRT_EphemTab, pItem->iCursor);
      assert( pItem->isPopulated==0 );
      explainSetInteger(pItem->iSelectId, pParse->iNextSelectId);
      sqlite3Select(pParse, pSub, &dest);
      pItem->isPopulated = 1;
      pItem->pTab->nRowEst = (unsigned)pSub->nSelectRow;
    }
    if( /*pParse->nErr ||*/ db->mallocFailed ){
      goto select_end;
    }
    pParse->nHeight -= sqlite3SelectExprHeight(p);
    pTabList = p->pSrc;
    if( !IgnorableOrderby(pDest) ){

        pLoop->pRightmost = p;
        pLoop->pNext = pRight;
        pRight = pLoop;
      }
      mxSelect = db->aLimit[SQLITE_LIMIT_COMPOUND_SELECT];
      if( mxSelect && cnt>mxSelect ){
        sqlite3ErrorMsg(pParse, "too many terms in compound SELECT");
        goto select_end;
        return 1;
      }
    }
    rc = multiSelect(pParse, p, pDest);
    return multiSelect(pParse, p, pDest);
    explainSetInteger(pParse->iSelectId, iRestoreSelectId);
    return rc;
  }
#endif

  /* If possible, rewrite the query to use GROUP BY instead of DISTINCT.
  ** GROUP BY might use an index, DISTINCT never does.
  */
  assert( p->pGroupBy==0 || (p->selFlags & SF_Aggregate)!=0 );
  if( (p->selFlags & (SF_Distinct|SF_Aggregate))==SF_Distinct ){
    p->pGroupBy = sqlite3ExprListDup(db, p->pEList, 0);
    pGroupBy = p->pGroupBy;
    p->selFlags &= ~SF_Distinct;
    isDistinct = 0;
  }

  /* If there is both a GROUP BY and an ORDER BY clause and they are
  ** identical, then disable the ORDER BY clause since the GROUP BY
  ** will cause elements to come out in the correct order.  This is
  ** an optimization - the correct answer should result regardless.
  ** Use the SQLITE_GroupByOrder flag with SQLITE_TESTCTRL_OPTIMIZER

  if( pDest->eDest==SRT_EphemTab ){
    sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pDest->iParm, pEList->nExpr);
  }

  /* Set the limiter.
  */
  iEnd = sqlite3VdbeMakeLabel(v);
  p->nSelectRow = (double)LARGEST_INT64;
  computeLimitRegisters(pParse, p, iEnd);

  /* Open a virtual index to use for the distinct set.
  */
  if( p->selFlags & SF_Distinct ){
  if( isDistinct ){
    KeyInfo *pKeyInfo;
    assert( isAgg || pGroupBy );
    distinct = pParse->nTab++;
    pKeyInfo = keyInfoFromExprList(pParse, p->pEList);
    sqlite3VdbeAddOp4(v, OP_OpenEphemeral, distinct, 0, 0,
                        (char*)pKeyInfo, P4_KEYINFO_HANDOFF);
    sqlite3VdbeChangeP5(v, BTREE_UNORDERED);
  }else{
    distinct = -1;
  }

  /* Aggregate and non-aggregate queries are handled differently */
  if( !isAgg && pGroupBy==0 ){
    /* This case is for non-aggregate queries
    ** Begin the database scan
    */
    pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, &pOrderBy, 0);
    if( pWInfo==0 ) goto select_end;
    if( pWInfo->nRowOut < p->nSelectRow ) p->nSelectRow = pWInfo->nRowOut;

    /* If sorting index that was created by a prior OP_OpenEphemeral 
    ** instruction ended up not being needed, then change the OP_OpenEphemeral
    ** into an OP_Noop.
    */
    if( addrSortIndex>=0 && pOrderBy==0 ){
      sqlite3VdbeChangeToNoop(v, addrSortIndex, 1);

      for(k=p->pEList->nExpr, pItem=p->pEList->a; k>0; k--, pItem++){
        pItem->iAlias = 0;
      }
      for(k=pGroupBy->nExpr, pItem=pGroupBy->a; k>0; k--, pItem++){
        pItem->iAlias = 0;
      }
      if( p->nSelectRow>(double)100 ) p->nSelectRow = (double)100;
    }else{
      p->nSelectRow = (double)1;
    }

 
    /* Create a label to jump to when we want to abort the query */
    addrEnd = sqlite3VdbeMakeLabel(v);

    /* Convert TK_COLUMN nodes into TK_AGG_COLUMN and make entries in

        ** in sorted order
        */
        int regBase;
        int regRecord;
        int nCol;
        int nGroupBy;

        explainTempTable(pParse, 
            isDistinct && !(p->selFlags&SF_Distinct)?"DISTINCT":"GROUP BY");

        groupBySort = 1;
        nGroupBy = pGroupBy->nExpr;
        nCol = nGroupBy + 1;
        j = nGroupBy+1;
        for(i=0; i<sAggInfo.nColumn; i++){
          if( sAggInfo.aCol[i].iSorterColumn>=j ){
            nCol++;

                      pDest, addrEnd, addrEnd);
      sqlite3ExprListDelete(db, pDel);
    }
    sqlite3VdbeResolveLabel(v, addrEnd);
    
  } /* endif aggregate query */

  if( distinct>=0 ){
    explainTempTable(pParse, "DISTINCT");
  }

  /* If there is an ORDER BY clause, then we need to sort the results
  ** and send them to the callback one by one.
  */
  if( pOrderBy ){
    explainTempTable(pParse, "ORDER BY");
    generateSortTail(pParse, p, v, pEList->nExpr, pDest);
  }

  /* Jump here to skip this query
  */
  sqlite3VdbeResolveLabel(v, iEnd);

  /* The SELECT was successfully coded.   Set the return code to 0
  ** to indicate no errors.
  */
  rc = 0;

  /* Control jumps to here if an error is encountered above, or upon
  ** successful coding of the SELECT.
  */
select_end:
  explainSetInteger(pParse->iSelectId, iRestoreSelectId);

  /* Identify column names if results of the SELECT are to be output.
  */
  if( rc==SQLITE_OK && pDest->eDest==SRT_Output ){
    generateColumnNames(pParse, pTabList, pEList);
  }

        pTab->aCol = pParse->pNewTable->aCol;
        pTab->nCol = pParse->pNewTable->nCol;
        pParse->pNewTable->nCol = 0;
        pParse->pNewTable->aCol = 0;
      }
      db->pVTab = 0;
    }else{
      sqlite3Error(db, SQLITE_ERROR, (zErr ? "%s" : 0), zErr);
      sqlite3Error(db, SQLITE_ERROR, zErr);
      sqlite3DbFree(db, zErr);
      rc = SQLITE_ERROR;
    }
    pParse->declareVtab = 0;
  
    if( pParse->pVdbe ){
      sqlite3VdbeFinalize(pParse->pVdbe);

/*
** A WhereCost object records a lookup strategy and the estimated
** cost of pursuing that strategy.
*/
struct WhereCost {
  WherePlan plan;    /* The lookup strategy */
  double rCost;      /* Overall cost of pursuing this search strategy */
  double nRow;       /* Estimated number of output rows */
  Bitmask used;      /* Bitmask of cursors used by this plan */
};

/*
** Bitmasks for the operators that indices are able to exploit.  An
** OR-ed combination of these values can be used when searching for
** terms in the where clause.

#define WHERE_ROWID_EQ     0x00001000  /* rowid=EXPR or rowid IN (...) */
#define WHERE_ROWID_RANGE  0x00002000  /* rowid<EXPR and/or rowid>EXPR */
#define WHERE_COLUMN_EQ    0x00010000  /* x=EXPR or x IN (...) or x IS NULL */
#define WHERE_COLUMN_RANGE 0x00020000  /* x<EXPR and/or x>EXPR */
#define WHERE_COLUMN_IN    0x00040000  /* x IN (...) */
#define WHERE_COLUMN_NULL  0x00080000  /* x IS NULL */
#define WHERE_INDEXED      0x000f0000  /* Anything that uses an index */
#define WHERE_NOT_FULLSCAN 0x100f3000  /* Does not do a full table scan */
#define WHERE_NOT_FULLSCAN 0x000f3000  /* Does not do a full table scan */
#define WHERE_IN_ABLE      0x000f1000  /* Able to support an IN operator */
#define WHERE_TOP_LIMIT    0x00100000  /* x<EXPR or x<=EXPR constraint */
#define WHERE_BTM_LIMIT    0x00200000  /* x>EXPR or x>=EXPR constraint */
#define WHERE_BOTH_LIMIT   0x00300000  /* Both x>EXPR and x<EXPR */
#define WHERE_IDX_ONLY     0x00800000  /* Use index only - omit table */
#define WHERE_ORDERBY      0x01000000  /* Output will appear in correct order */
#define WHERE_REVERSE      0x02000000  /* Scan in reverse order */
#define WHERE_UNIQUE       0x04000000  /* Selects no more than one row */
#define WHERE_VIRTUALTABLE 0x08000000  /* Use virtual-table processing */
#define WHERE_MULTI_OR     0x10000000  /* OR using multiple indices */
#define WHERE_TEMP_INDEX   0x20000000  /* Uses an ephemeral index */

){
#ifndef SQLITE_OMIT_OR_OPTIMIZATION
  const int iCur = pSrc->iCursor;   /* The cursor of the table to be accessed */
  const Bitmask maskSrc = getMask(pWC->pMaskSet, iCur);  /* Bitmask for pSrc */
  WhereTerm * const pWCEnd = &pWC->a[pWC->nTerm];        /* End of pWC->a[] */
  WhereTerm *pTerm;                 /* A single term of the WHERE clause */

  /* No OR-clause optimization allowed if the INDEXED BY or NOT INDEXED clauses
  /* No OR-clause optimization allowed if the NOT INDEXED clause is used */
  ** are used */
  if( pSrc->notIndexed || pSrc->pIndex!=0 ){
  if( pSrc->notIndexed ){
    return;
  }

  /* Search the WHERE clause terms for a usable WO_OR term. */
  for(pTerm=pWC->a; pTerm<pWCEnd; pTerm++){
    if( pTerm->eOperator==WO_OR 
     && ((pTerm->prereqAll & ~maskSrc) & notReady)==0

          tempWC.a = pOrTerm;
          tempWC.nTerm = 1;
          bestIndex(pParse, &tempWC, pSrc, notReady, notValid, 0, &sTermCost);
        }else{
          continue;
        }
        rTotal += sTermCost.rCost;
        nRow += sTermCost.plan.nRow;
        nRow += sTermCost.nRow;
        used |= sTermCost.used;
        if( rTotal>=pCost->rCost ) break;
      }

      /* If there is an ORDER BY clause, increase the scan cost to account 
      ** for the cost of the sort. */
      if( pOrderBy!=0 ){
        WHERETRACE(("... sorting increases OR cost %.9g to %.9g\n",
                    rTotal, rTotal+nRow*estLog(nRow)));
        rTotal += nRow*estLog(nRow);
      }

      /* If the cost of scanning using this OR term for optimization is
      ** less than the current cost stored in pCost, replace the contents
      ** of pCost. */
      WHERETRACE(("... multi-index OR cost=%.9g nrow=%.9g\n", rTotal, nRow));
      if( rTotal<pCost->rCost ){
        pCost->rCost = rTotal;
        pCost->nRow = nRow;
        pCost->used = used;
        pCost->plan.nRow = nRow;
        pCost->plan.wsFlags = flags;
        pCost->plan.u.pTerm = pTerm;
      }
    }
  }
#endif /* SQLITE_OMIT_OR_OPTIMIZATION */
}

  /* Search for any equality comparison term */
  pWCEnd = &pWC->a[pWC->nTerm];
  for(pTerm=pWC->a; pTerm<pWCEnd; pTerm++){
    if( termCanDriveIndex(pTerm, pSrc, notReady) ){
      WHERETRACE(("auto-index reduces cost from %.2f to %.2f\n",
                    pCost->rCost, costTempIdx));
      pCost->rCost = costTempIdx;
      pCost->plan.nRow = logN + 1;
      pCost->nRow = logN + 1;
      pCost->plan.wsFlags = WHERE_TEMP_INDEX;
      pCost->used = pTerm->prereqRight;
      break;
    }
  }
}
#else

      notReady, nRow, cost, used
    ));

    /* If this index is the best we have seen so far, then record this
    ** index and its cost in the pCost structure.
    */
    if( (!pIdx || wsFlags)
     && (cost<pCost->rCost || (cost<=pCost->rCost && nRow<pCost->plan.nRow))
     && (cost<pCost->rCost || (cost<=pCost->rCost && nRow<pCost->nRow))
    ){
      pCost->rCost = cost;
      pCost->nRow = nRow;
      pCost->used = used;
      pCost->plan.nRow = nRow;
      pCost->plan.wsFlags = (wsFlags&wsFlagMask);
      pCost->plan.nEq = nEq;
      pCost->plan.u.pIdx = pIdx;
    }

    /* If there was an INDEXED BY clause, then only that one index is
    ** considered. */

        }
      }
    }
  }
  *pzAff = zAff;
  return regBase;
}

#ifndef SQLITE_OMIT_EXPLAIN
/*
** This routine is a helper for explainIndexRange() below
**
** pStr holds the text of an expression that we are building up one term
** at a time.  This routine adds a new term to the end of the expression.
** Terms are separated by AND so add the "AND" text for second and subsequent
** terms only.
*/
static void explainAppendTerm(
  StrAccum *pStr,             /* The text expression being built */
  int iTerm,                  /* Index of this term.  First is zero */
  const char *zColumn,        /* Name of the column */
  const char *zOp             /* Name of the operator */
){
  if( iTerm ) sqlite3StrAccumAppend(pStr, " AND ", 5);
  sqlite3StrAccumAppend(pStr, zColumn, -1);
  sqlite3StrAccumAppend(pStr, zOp, 1);
  sqlite3StrAccumAppend(pStr, "?", 1);
}

/*
** Argument pLevel describes a strategy for scanning table pTab. This 
** function returns a pointer to a string buffer containing a description
** of the subset of table rows scanned by the strategy in the form of an
** SQL expression. Or, if all rows are scanned, NULL is returned.
**
** For example, if the query:
**
**   SELECT * FROM t1 WHERE a=1 AND b>2;
**
** is run and there is an index on (a, b), then this function returns a
** string similar to:
**
**   "a=? AND b>?"
**
** The returned pointer points to memory obtained from sqlite3DbMalloc().
** It is the responsibility of the caller to free the buffer when it is
** no longer required.
*/
static char *explainIndexRange(sqlite3 *db, WhereLevel *pLevel, Table *pTab){
  WherePlan *pPlan = &pLevel->plan;
  Index *pIndex = pPlan->u.pIdx;
  int nEq = pPlan->nEq;
  int i, j;
  Column *aCol = pTab->aCol;
  int *aiColumn = pIndex->aiColumn;
  StrAccum txt;

  if( nEq==0 && (pPlan->wsFlags & (WHERE_BTM_LIMIT|WHERE_TOP_LIMIT))==0 ){
    return 0;
  }
  sqlite3StrAccumInit(&txt, 0, 0, SQLITE_MAX_LENGTH);
  txt.db = db;
  sqlite3StrAccumAppend(&txt, " (", 2);
  for(i=0; i<nEq; i++){
    explainAppendTerm(&txt, i, aCol[aiColumn[i]].zName, "=");
  }

  j = i;
  if( pPlan->wsFlags&WHERE_BTM_LIMIT ){
    explainAppendTerm(&txt, i++, aCol[aiColumn[j]].zName, ">");
  }
  if( pPlan->wsFlags&WHERE_TOP_LIMIT ){
    explainAppendTerm(&txt, i, aCol[aiColumn[j]].zName, "<");
  }
  sqlite3StrAccumAppend(&txt, ")", 1);
  return sqlite3StrAccumFinish(&txt);
}

/*
** This function is a no-op unless currently processing an EXPLAIN QUERY PLAN
** command. If the query being compiled is an EXPLAIN QUERY PLAN, a single
** record is added to the output to describe the table scan strategy in 
** pLevel.
*/
static void explainOneScan(
  Parse *pParse,                  /* Parse context */
  SrcList *pTabList,              /* Table list this loop refers to */
  WhereLevel *pLevel,             /* Scan to write OP_Explain opcode for */
  int iLevel,                     /* Value for "level" column of output */
  int iFrom,                      /* Value for "from" column of output */
  u16 wctrlFlags                  /* Flags passed to sqlite3WhereBegin() */
){
  if( pParse->explain==2 ){
    u32 flags = pLevel->plan.wsFlags;
    struct SrcList_item *pItem = &pTabList->a[pLevel->iFrom];
    Vdbe *v = pParse->pVdbe;      /* VM being constructed */
    sqlite3 *db = pParse->db;     /* Database handle */
    char *zMsg;                   /* Text to add to EQP output */
    sqlite3_int64 nRow;           /* Expected number of rows visited by scan */
    int iId = pParse->iSelectId;  /* Select id (left-most output column) */
    int isSearch;                 /* True for a SEARCH. False for SCAN. */

    if( (flags&WHERE_MULTI_OR) || (wctrlFlags&WHERE_ONETABLE_ONLY) ) return;

    isSearch = (pLevel->plan.nEq>0)
             || (flags&(WHERE_BTM_LIMIT|WHERE_TOP_LIMIT))!=0
             || (wctrlFlags&(WHERE_ORDERBY_MIN|WHERE_ORDERBY_MAX));

    zMsg = sqlite3MPrintf(db, "%s", isSearch?"SEARCH":"SCAN");
    if( pItem->pSelect ){
      zMsg = sqlite3MAppendf(db, zMsg, "%s SUBQUERY %d", zMsg,pItem->iSelectId);
    }else{
      zMsg = sqlite3MAppendf(db, zMsg, "%s TABLE %s", zMsg, pItem->zName);
    }

    if( pItem->zAlias ){
      zMsg = sqlite3MAppendf(db, zMsg, "%s AS %s", zMsg, pItem->zAlias);
    }
    if( (flags & WHERE_INDEXED)!=0 ){
      char *zWhere = explainIndexRange(db, pLevel, pItem->pTab);
      zMsg = sqlite3MAppendf(db, zMsg, "%s USING %s%sINDEX%s%s%s", zMsg, 
          ((flags & WHERE_TEMP_INDEX)?"AUTOMATIC ":""),
          ((flags & WHERE_IDX_ONLY)?"COVERING ":""),
          ((flags & WHERE_TEMP_INDEX)?"":" "),
          ((flags & WHERE_TEMP_INDEX)?"": pLevel->plan.u.pIdx->zName),
          zWhere
      );
      sqlite3DbFree(db, zWhere);
    }else if( flags & (WHERE_ROWID_EQ|WHERE_ROWID_RANGE) ){
      zMsg = sqlite3MAppendf(db, zMsg, "%s USING INTEGER PRIMARY KEY", zMsg);

      if( flags&WHERE_ROWID_EQ ){
        zMsg = sqlite3MAppendf(db, zMsg, "%s (rowid=?)", zMsg);
      }else if( (flags&WHERE_BOTH_LIMIT)==WHERE_BOTH_LIMIT ){
        zMsg = sqlite3MAppendf(db, zMsg, "%s (rowid>? AND rowid<?)", zMsg);
      }else if( flags&WHERE_BTM_LIMIT ){
        zMsg = sqlite3MAppendf(db, zMsg, "%s (rowid>?)", zMsg);
      }else if( flags&WHERE_TOP_LIMIT ){
        zMsg = sqlite3MAppendf(db, zMsg, "%s (rowid<?)", zMsg);
      }
    }
#ifndef SQLITE_OMIT_VIRTUALTABLE
    else if( (flags & WHERE_VIRTUALTABLE)!=0 ){
      sqlite3_index_info *pVtabIdx = pLevel->plan.u.pVtabIdx;
      zMsg = sqlite3MAppendf(db, zMsg, "%s VIRTUAL TABLE INDEX %d:%s", zMsg,
                  pVtabIdx->idxNum, pVtabIdx->idxStr);
    }
#endif
    if( wctrlFlags&(WHERE_ORDERBY_MIN|WHERE_ORDERBY_MAX) ){
      testcase( wctrlFlags & WHERE_ORDERBY_MIN );
      nRow = 1;
    }else{
      nRow = (sqlite3_int64)pLevel->plan.nRow;
    }
    zMsg = sqlite3MAppendf(db, zMsg, "%s (~%lld rows)", zMsg, nRow);
    sqlite3VdbeAddOp4(v, OP_Explain, iId, iLevel, iFrom, zMsg, P4_DYNAMIC);
  }
}
#else
# define explainOneScan(u,v,w,x,y,z)
#endif /* SQLITE_OMIT_EXPLAIN */


/*
** Generate code for the start of the iLevel-th loop in the WHERE clause
** implementation described by pWInfo.
*/
static Bitmask codeOneLoopStart(
  WhereInfo *pWInfo,   /* Complete information about the WHERE clause */

    /* If there are inequality constraints, check that the value
    ** of the table column that the inequality contrains is not NULL.
    ** If it is, jump to the next iteration of the loop.
    */
    r1 = sqlite3GetTempReg(pParse);
    testcase( pLevel->plan.wsFlags & WHERE_BTM_LIMIT );
    testcase( pLevel->plan.wsFlags & WHERE_TOP_LIMIT );
    if( (pLevel->plan.wsFlags & (WHERE_BTM_LIMIT|WHERE_TOP_LIMIT))!=0 ){
    if( pLevel->plan.wsFlags & (WHERE_BTM_LIMIT|WHERE_TOP_LIMIT) ){
      sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, nEq, r1);
      sqlite3VdbeAddOp2(v, OP_IsNull, r1, addrCont);
    }
    sqlite3ReleaseTempReg(pParse, r1);

    /* Seek the table cursor, if required */
    disableTerm(pLevel, pRangeStart);

      if( pOrTerm->leftCursor==iCur || pOrTerm->eOperator==WO_AND ){
        WhereInfo *pSubWInfo;          /* Info for single OR-term scan */
        /* Loop through table entries that match term pOrTerm. */
        pSubWInfo = sqlite3WhereBegin(pParse, pOrTab, pOrTerm->pExpr, 0,
                        WHERE_OMIT_OPEN | WHERE_OMIT_CLOSE |
                        WHERE_FORCE_TABLE | WHERE_ONETABLE_ONLY);
        if( pSubWInfo ){
          explainOneScan(
              pParse, pOrTab, &pSubWInfo->a[0], iLevel, pLevel->iFrom, 0
          );
          if( (wctrlFlags & WHERE_DUPLICATES_OK)==0 ){
            int iSet = ((ii==pOrWc->nTerm-1)?-1:ii);
            int r;
            r = sqlite3ExprCodeGetColumn(pParse, pTabItem->pTab, -1, iCur, 
                                         regRowid);
            sqlite3VdbeAddOp4Int(v, OP_RowSetTest, regRowset,
                                 sqlite3VdbeCurrentAddr(v)+2, r, iSet);

    Bitmask m;                  /* Bitmask value for j or bestJ */
    int isOptimal;              /* Iterator for optimal/non-optimal search */
    int nUnconstrained;         /* Number tables without INDEXED BY */
    Bitmask notIndexed;         /* Mask of tables that cannot use an index */

    memset(&bestPlan, 0, sizeof(bestPlan));
    bestPlan.rCost = SQLITE_BIG_DBL;
    WHERETRACE(("*** Begin search for loop %d ***\n", i));

    /* Loop through the remaining entries in the FROM clause to find the
    ** next nested loop. The loop tests all FROM clause entries
    ** either once or twice. 
    **
    ** The first test is always performed if there are two or more entries
    ** remaining and never performed if there is only one FROM clause entry

          if( j==iFrom ) iFrom++;
          continue;
        }
        mask = (isOptimal ? m : notReady);
        pOrderBy = ((i==0 && ppOrderBy )?*ppOrderBy:0);
        if( pTabItem->pIndex==0 ) nUnconstrained++;
  
        WHERETRACE(("=== trying table %d with isOptimal=%d ===\n",
                    j, isOptimal));
        assert( pTabItem->pTab );
#ifndef SQLITE_OMIT_VIRTUALTABLE
        if( IsVirtual(pTabItem->pTab) ){
          sqlite3_index_info **pp = &pWInfo->a[j].pIdxInfo;
          bestVirtualIndex(pParse, pWC, pTabItem, mask, notReady, pOrderBy,
                           &sCost, pp);
        }else 

        */
        if( (sCost.used&notReady)==0                       /* (1) */
            && (bestJ<0 || (notIndexed&m)!=0               /* (2) */
                || (sCost.plan.wsFlags & WHERE_NOT_FULLSCAN)!=0)
            && (nUnconstrained==0 || pTabItem->pIndex==0   /* (3) */
                || NEVER((sCost.plan.wsFlags & WHERE_NOT_FULLSCAN)!=0))
            && (bestJ<0 || sCost.rCost<bestPlan.rCost      /* (4) */
                || (sCost.rCost<=bestPlan.rCost 
                || (sCost.rCost<=bestPlan.rCost && sCost.nRow<bestPlan.nRow))
                 && sCost.plan.nRow<bestPlan.plan.nRow))
        ){
          WHERETRACE(("=== table %d is best so far"
                      " with cost=%g and nRow=%g\n",
                      j, sCost.rCost, sCost.plan.nRow));
          WHERETRACE(("... best so far with cost=%g and nRow=%g\n",
                      sCost.rCost, sCost.nRow));
          bestPlan = sCost;
          bestJ = j;
        }
        if( doNotReorder ) break;
      }
    }
    assert( bestJ>=0 );
    assert( notReady & getMask(pMaskSet, pTabList->a[bestJ].iCursor) );
    WHERETRACE(("*** Optimizer selects table %d for loop %d"
    WHERETRACE(("*** Optimizer selects table %d for loop %d\n", bestJ,
                " with cost=%g and nRow=%g\n",
                bestJ, pLevel-pWInfo->a, bestPlan.rCost, bestPlan.plan.nRow));
           pLevel-pWInfo->a));
    if( (bestPlan.plan.wsFlags & WHERE_ORDERBY)!=0 ){
      *ppOrderBy = 0;
    }
    andFlags &= bestPlan.plan.wsFlags;
    pLevel->plan = bestPlan.plan;
    testcase( bestPlan.plan.wsFlags & WHERE_INDEXED );
    testcase( bestPlan.plan.wsFlags & WHERE_TEMP_INDEX );
    if( bestPlan.plan.wsFlags & (WHERE_INDEXED|WHERE_TEMP_INDEX) ){
      pLevel->iIdxCur = pParse->nTab++;
    }else{
      pLevel->iIdxCur = -1;
    }
    notReady &= ~getMask(pMaskSet, pTabList->a[bestJ].iCursor);
    pLevel->iFrom = (u8)bestJ;
    if( bestPlan.plan.nRow>=(double)1 ){
      pParse->nQueryLoop *= bestPlan.plan.nRow;
    if( bestPlan.nRow>=(double)1 ) pParse->nQueryLoop *= bestPlan.nRow;
    }

    /* Check that if the table scanned by this loop iteration had an
    ** INDEXED BY clause attached to it, that the named index is being
    ** used for the scan. If not, then query compilation has failed.
    ** Return an error.
    */
    pIdx = pTabList->a[bestJ].pIndex;

  }

  /* Open all tables in the pTabList and any indices selected for
  ** searching those tables.
  */
  sqlite3CodeVerifySchema(pParse, -1); /* Insert the cookie verifier Goto */
  notReady = ~(Bitmask)0;
  pWInfo->nRowOut = (double)1;
  for(i=0, pLevel=pWInfo->a; i<nTabList; i++, pLevel++){
    Table *pTab;     /* Table to open */
    int iDb;         /* Index of database containing table/index */

#ifndef SQLITE_OMIT_EXPLAIN
    if( pParse->explain==2 ){
      char *zMsg;
      struct SrcList_item *pItem = &pTabList->a[pLevel->iFrom];
      zMsg = sqlite3MPrintf(db, "TABLE %s", pItem->zName);
      if( pItem->zAlias ){
        zMsg = sqlite3MAppendf(db, zMsg, "%s AS %s", zMsg, pItem->zAlias);
      }
      if( (pLevel->plan.wsFlags & WHERE_TEMP_INDEX)!=0 ){
        zMsg = sqlite3MAppendf(db, zMsg, "%s WITH AUTOMATIC INDEX", zMsg);
      }else if( (pLevel->plan.wsFlags & WHERE_INDEXED)!=0 ){
        zMsg = sqlite3MAppendf(db, zMsg, "%s WITH INDEX %s",
           zMsg, pLevel->plan.u.pIdx->zName);
      }else if( pLevel->plan.wsFlags & WHERE_MULTI_OR ){
        zMsg = sqlite3MAppendf(db, zMsg, "%s VIA MULTI-INDEX UNION", zMsg);
      }else if( pLevel->plan.wsFlags & (WHERE_ROWID_EQ|WHERE_ROWID_RANGE) ){
        zMsg = sqlite3MAppendf(db, zMsg, "%s USING PRIMARY KEY", zMsg);
      }
#ifndef SQLITE_OMIT_VIRTUALTABLE
      else if( (pLevel->plan.wsFlags & WHERE_VIRTUALTABLE)!=0 ){
        sqlite3_index_info *pVtabIdx = pLevel->plan.u.pVtabIdx;
        zMsg = sqlite3MAppendf(db, zMsg, "%s VIRTUAL TABLE INDEX %d:%s", zMsg,
                    pVtabIdx->idxNum, pVtabIdx->idxStr);
      }
#endif
      if( pLevel->plan.wsFlags & WHERE_ORDERBY ){
        zMsg = sqlite3MAppendf(db, zMsg, "%s ORDER BY", zMsg);
      }
      sqlite3VdbeAddOp4(v, OP_Explain, i, pLevel->iFrom, 0, zMsg, P4_DYNAMIC);
    }
#endif /* SQLITE_OMIT_EXPLAIN */
    pTabItem = &pTabList->a[pLevel->iFrom];
    pTab = pTabItem->pTab;
    pLevel->iTabCur = pTabItem->iCursor;
    pWInfo->nRowOut *= pLevel->plan.nRow;
    iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
    if( (pTab->tabFlags & TF_Ephemeral)!=0 || pTab->pSelect ){
      /* Do nothing */
    }else
#ifndef SQLITE_OMIT_VIRTUALTABLE
    if( (pLevel->plan.wsFlags & WHERE_VIRTUALTABLE)!=0 ){
      const char *pVTab = (const char *)sqlite3GetVTable(db, pTab);

  /* Generate the code to do the search.  Each iteration of the for
  ** loop below generates code for a single nested loop of the VM
  ** program.
  */
  notReady = ~(Bitmask)0;
  for(i=0; i<nTabList; i++){
    WhereLevel *pLevel = &pWInfo->a[i];
    explainOneScan(pParse, pTabList, pLevel, i, pLevel->iFrom, wctrlFlags);
    notReady = codeOneLoopStart(pWInfo, i, wctrlFlags, notReady);
    pWInfo->iContinue = pLevel->addrCont;
    pWInfo->iContinue = pWInfo->a[i].addrCont;
  }

#ifdef SQLITE_TEST  /* For testing and debugging use only */
  /* Record in the query plan information about the current table
  ** and the index used to access it (if any).  If the table itself
  ** is not used, its name is just '{}'.  If no index is used
  ** the index is listed as "{}".  If the primary key is used the

          p->xCmp = 0;
        }
      }
    }
  }

  pColl = sqlite3FindCollSeq(db, (u8)enc2, zName, 1);
  if( pColl==0 ) return SQLITE_NOMEM;
  pColl->xCmp = xCompare;
  pColl->pUser = pCtx;
  pColl->xDel = xDel;
  pColl->enc = (u8)(enc2 | (enc & SQLITE_UTF16_ALIGNED));
  pColl->type = collType;
  if( pColl ){
    pColl->xCmp = xCompare;
    pColl->pUser = pCtx;
    pColl->xDel = xDel;
    pColl->enc = (u8)(enc2 | (enc & SQLITE_UTF16_ALIGNED));
    pColl->type = collType;
  }
  sqlite3Error(db, SQLITE_OK, 0);
  return SQLITE_OK;
}


/*
** This array defines hard upper bounds on limit values.  The

** amalgamation.
*/
#ifndef SQLITE_AMALGAMATION
/*
** Macros indicating that conditional expressions are always true or
** false.
*/
#ifdef SQLITE_COVERAGE_TEST
# define ALWAYS(x) (1)
# define NEVER(X)  (0)
#else
# define ALWAYS(x) (x)
# define NEVER(X)  (x)
#endif

/*
** Internal types used by SQLite.
*/
typedef unsigned char u8;         /* 1-byte (or larger) unsigned integer */
typedef short int i16;            /* 2-byte (or larger) signed integer */
typedef unsigned int u32;         /* 4-byte unsigned integer */
typedef sqlite3_uint64 u64;       /* 8-byte unsigned integer */
/*
** Macro used to suppress compiler warnings for unused parameters.
*/
#define UNUSED_PARAMETER(x) (void)(x)
#endif

typedef struct Fts3Table Fts3Table;
typedef struct Fts3Cursor Fts3Cursor;
typedef struct Fts3Expr Fts3Expr;
typedef struct Fts3Phrase Fts3Phrase;
typedef struct Fts3PhraseToken Fts3PhraseToken;

typedef struct Fts3SegFilter Fts3SegFilter;
typedef struct Fts3DeferredToken Fts3DeferredToken;
typedef struct Fts3SegReader Fts3SegReader;
typedef struct Fts3SegReaderArray Fts3SegReaderArray;
typedef struct Fts3SegFilter Fts3SegFilter;

/*
** A connection to a fulltext index is an instance of the following
** structure. The xCreate and xConnect methods create an instance
** of this structure and xDestroy and xDisconnect free that instance.
** All other methods receive a pointer to the structure as one of their
** arguments.
*/
struct Fts3Table {
  sqlite3_vtab base;              /* Base class used by SQLite core */
  sqlite3 *db;                    /* The database connection */
  const char *zDb;                /* logical database name */
  const char *zName;              /* virtual table name */
  int nColumn;                    /* number of named columns in virtual table */
  char **azColumn;                /* column names.  malloced */
  sqlite3_tokenizer *pTokenizer;  /* tokenizer for inserts and queries */

  /* Precompiled statements used by the implementation. Each of these 
  ** statements is run and reset within a single virtual table API call. 
  */
  sqlite3_stmt *aStmt[24];
  sqlite3_stmt *aStmt[25];

  /* Pointer to string containing the SQL:
  **
  ** "SELECT block FROM %_segments WHERE blockid BETWEEN ? AND ? 
  **    ORDER BY blockid"
  */
  char *zSelectLeaves;
  int nLeavesStmt;                /* Valid statements in aLeavesStmt */
  int nLeavesTotal;               /* Total number of prepared leaves stmts */
  int nLeavesAlloc;               /* Allocated size of aLeavesStmt */
  sqlite3_stmt **aLeavesStmt;     /* Array of prepared zSelectLeaves stmts */

  int nNodeSize;                  /* Soft limit for node size */
  u8 bHasStat;                    /* True if %_stat table exists */
  u8 bHasContent;                 /* True if %_content table exists */
  u8 bHasDocsize;                 /* True if %_docsize table exists */
  int nPgsz;                      /* Page size for host database */
  char *zSegmentsTbl;             /* Name of %_segments table */
  sqlite3_blob *pSegments;        /* Blob handle open on %_segments table */

  /* The following hash table is used to buffer pending index updates during
  ** transactions. Variable nPendingData estimates the memory size of the 
  ** pending data, including hash table overhead, but not malloc overhead. 
  ** When nPendingData exceeds nMaxPendingData, the buffer is flushed 
  ** automatically. Variable iPrevDocid is the docid of the most recently
  ** inserted record.

struct Fts3Cursor {
  sqlite3_vtab_cursor base;       /* Base class used by SQLite core */
  i16 eSearch;                    /* Search strategy (see below) */
  u8 isEof;                       /* True if at End Of Results */
  u8 isRequireSeek;               /* True if must seek pStmt to %_content row */
  sqlite3_stmt *pStmt;            /* Prepared statement in use by the cursor */
  Fts3Expr *pExpr;                /* Parsed MATCH query string */
  Fts3DeferredToken *pDeferred;   /* Deferred search tokens, if any */
  sqlite3_int64 iPrevId;          /* Previous id read from aDoclist */
  char *pNextId;                  /* Pointer into the body of aDoclist */
  char *aDoclist;                 /* List of docids for full-text queries */
  int nDoclist;                   /* Size of buffer at aDoclist */
  int isMatchinfoNeeded;          /* True when aMatchinfo[] needs filling in */
  u32 *aMatchinfo;                /* Information about most recent match */
  int eEvalmode;                  /* An FTS3_EVAL_XX constant */
  int nRowAvg;                    /* Average size of database rows, in pages */
};

#define FTS3_EVAL_FILTER    0
#define FTS3_EVAL_NEXT      1
#define FTS3_EVAL_MATCHINFO 2

/*
** The Fts3Cursor.eSearch member is always set to one of the following.
** Actualy, Fts3Cursor.eSearch can be greater than or equal to
** FTS3_FULLTEXT_SEARCH.  If so, then Fts3Cursor.eSearch - 2 is the index
** of the column to be searched.  For example, in
**
**     CREATE VIRTUAL TABLE ex1 USING fts3(a,b,c,d);

#define FTS3_FULLSCAN_SEARCH 0    /* Linear scan of %_content table */
#define FTS3_DOCID_SEARCH    1    /* Lookup by rowid on %_content table */
#define FTS3_FULLTEXT_SEARCH 2    /* Full-text index search */

/*
** A "phrase" is a sequence of one or more tokens that must match in
** sequence.  A single token is the base case and the most common case.
** For a sequence of tokens contained in double-quotes (i.e. "one two three")
** nToken will be the number of tokens in the string.
** For a sequence of tokens contained in "...", nToken will be the number
** of tokens in the string.
**
** The nDocMatch and nMatch variables contain data that may be used by the
** matchinfo() function. They are populated when the full-text index is 
** queried for hits on the phrase. If one or more tokens in the phrase
** are deferred, the nDocMatch and nMatch variables are populated based
** on the assumption that the 
*/
struct Fts3PhraseToken {
  char *z;                        /* Text of the token */
  int n;                          /* Number of bytes in buffer z */
  int isPrefix;                   /* True if token ends with a "*" character */
  int bFulltext;                  /* True if full-text index was used */
  Fts3SegReaderArray *pArray;     /* Segment-reader for this token */
  Fts3DeferredToken *pDeferred;   /* Deferred token object for this token */
};

struct Fts3Phrase {
  /* Variables populated by fts3_expr.c when parsing a MATCH expression */
  int nToken;                /* Number of tokens in the phrase */
  int iColumn;               /* Index of column this phrase must match */
  int isNot;                 /* Phrase prefixed by unary not (-) operator */
  struct PhraseToken {
    char *z;                 /* Text of the token */
    int n;                   /* Number of bytes in buffer pointed to by z */
    int isPrefix;            /* True if token ends in with a "*" character */
  Fts3PhraseToken aToken[1]; /* One entry for each token in the phrase */
  } aToken[1];               /* One entry for each token in the phrase */
};

/*
** A tree of these objects forms the RHS of a MATCH operator.
**
** If Fts3Expr.eType is either FTSQUERY_NEAR or FTSQUERY_PHRASE and isLoaded
** is true, then aDoclist points to a malloced buffer, size nDoclist bytes, 

#define FTSQUERY_NEAR   1
#define FTSQUERY_NOT    2
#define FTSQUERY_AND    3
#define FTSQUERY_OR     4
#define FTSQUERY_PHRASE 5


/* fts3_init.c */
SQLITE_PRIVATE int sqlite3Fts3DeleteVtab(int, sqlite3_vtab *);
SQLITE_PRIVATE int sqlite3Fts3InitVtab(int, sqlite3*, void*, int, const char*const*, 
                        sqlite3_vtab **, char **);

/* fts3_write.c */
SQLITE_PRIVATE int sqlite3Fts3UpdateMethod(sqlite3_vtab*,int,sqlite3_value**,sqlite3_int64*);
SQLITE_PRIVATE int sqlite3Fts3PendingTermsFlush(Fts3Table *);
SQLITE_PRIVATE void sqlite3Fts3PendingTermsClear(Fts3Table *);
SQLITE_PRIVATE int sqlite3Fts3Optimize(Fts3Table *);
SQLITE_PRIVATE int sqlite3Fts3SegReaderNew(Fts3Table *,int, sqlite3_int64,
  sqlite3_int64, sqlite3_int64, const char *, int, Fts3SegReader**);
SQLITE_PRIVATE int sqlite3Fts3SegReaderPending(Fts3Table*,const char*,int,int,Fts3SegReader**);
SQLITE_PRIVATE void sqlite3Fts3SegReaderFree(Fts3Table *, Fts3SegReader *);
SQLITE_PRIVATE int sqlite3Fts3SegReaderIterate(
  Fts3Table *, Fts3SegReader **, int, Fts3SegFilter *,
  int (*)(Fts3Table *, void *, char *, int, char *, int),  void *
);
SQLITE_PRIVATE int sqlite3Fts3SegReaderCost(Fts3Cursor *, Fts3SegReader *, int *);
SQLITE_PRIVATE int sqlite3Fts3ReadBlock(Fts3Table*, sqlite3_int64, char const**, int*);
SQLITE_PRIVATE int sqlite3Fts3AllSegdirs(Fts3Table*, sqlite3_stmt **);
SQLITE_PRIVATE int sqlite3Fts3MatchinfoDocsizeLocal(Fts3Cursor*, u32*);
SQLITE_PRIVATE int sqlite3Fts3MatchinfoDocsizeGlobal(Fts3Cursor*, u32*);
SQLITE_PRIVATE int sqlite3Fts3ReadLock(Fts3Table *);
SQLITE_PRIVATE int sqlite3Fts3ReadBlock(Fts3Table*, sqlite3_int64, char **, int*);

SQLITE_PRIVATE void sqlite3Fts3FreeDeferredTokens(Fts3Cursor *);
SQLITE_PRIVATE int sqlite3Fts3DeferToken(Fts3Cursor *, Fts3PhraseToken *, int);
SQLITE_PRIVATE int sqlite3Fts3CacheDeferredDoclists(Fts3Cursor *);
SQLITE_PRIVATE void sqlite3Fts3FreeDeferredDoclists(Fts3Cursor *);
SQLITE_PRIVATE char *sqlite3Fts3DeferredDoclist(Fts3DeferredToken *, int *);

SQLITE_PRIVATE void sqlite3Fts3SegmentsClose(Fts3Table *);

/* Flags allowed as part of the 4th argument to SegmentReaderIterate() */
#define FTS3_SEGMENT_REQUIRE_POS   0x00000001
#define FTS3_SEGMENT_IGNORE_EMPTY  0x00000002
#define FTS3_SEGMENT_COLUMN_FILTER 0x00000004
#define FTS3_SEGMENT_PREFIX        0x00000008

SQLITE_PRIVATE int sqlite3Fts3PutVarint(char *, sqlite3_int64);
SQLITE_PRIVATE int sqlite3Fts3GetVarint(const char *, sqlite_int64 *);
SQLITE_PRIVATE int sqlite3Fts3GetVarint32(const char *, int *);
SQLITE_PRIVATE int sqlite3Fts3VarintLen(sqlite3_uint64);
SQLITE_PRIVATE void sqlite3Fts3Dequote(char *);

SQLITE_PRIVATE char *sqlite3Fts3FindPositions(Fts3Expr *, sqlite3_int64, int);
SQLITE_PRIVATE int sqlite3Fts3ExprLoadDoclist(Fts3Cursor *, Fts3Expr *);
SQLITE_PRIVATE int sqlite3Fts3ExprLoadDoclist(Fts3Table *, Fts3Expr *);
SQLITE_PRIVATE int sqlite3Fts3ExprLoadFtDoclist(Fts3Cursor *, Fts3Expr *, char **, int *);
SQLITE_PRIVATE int sqlite3Fts3ExprNearTrim(Fts3Expr *, Fts3Expr *, int);

/* fts3_tokenizer.c */
SQLITE_PRIVATE const char *sqlite3Fts3NextToken(const char *, int *);
SQLITE_PRIVATE int sqlite3Fts3InitHashTable(sqlite3 *, Fts3Hash *, const char *);
SQLITE_PRIVATE int sqlite3Fts3InitTokenizer(Fts3Hash *pHash, const char *, 
    sqlite3_tokenizer **, char **
SQLITE_PRIVATE int sqlite3Fts3InitTokenizer(Fts3Hash *pHash, 
  const char *, sqlite3_tokenizer **, const char **, char **
);
SQLITE_PRIVATE int sqlite3Fts3IsIdChar(char);

/* fts3_snippet.c */
SQLITE_PRIVATE void sqlite3Fts3Offsets(sqlite3_context*, Fts3Cursor*);
SQLITE_PRIVATE void sqlite3Fts3Snippet(sqlite3_context *, Fts3Cursor *, const char *,
  const char *, const char *, int, int
);
SQLITE_PRIVATE void sqlite3Fts3Matchinfo(sqlite3_context *, Fts3Cursor *);

** The xDisconnect() virtual table method.
*/
static int fts3DisconnectMethod(sqlite3_vtab *pVtab){
  Fts3Table *p = (Fts3Table *)pVtab;
  int i;

  assert( p->nPendingData==0 );
  assert( p->pSegments==0 );

  /* Free any prepared statements held */
  for(i=0; i<SizeofArray(p->aStmt); i++){
    sqlite3_finalize(p->aStmt[i]);
  }
  for(i=0; i<p->nLeavesStmt; i++){
    sqlite3_finalize(p->aLeavesStmt[i]);
  }
  sqlite3_free(p->zSegmentsTbl);
  sqlite3_free(p->zSelectLeaves);
  sqlite3_free(p->aLeavesStmt);

  /* Invoke the tokenizer destructor to free the tokenizer. */
  p->pTokenizer->pModule->xDestroy(p->pTokenizer);

  sqlite3_free(p);
  return SQLITE_OK;
}

/*
** Construct one or more SQL statements from the format string given
** and then evaluate those statements. The success code is written
** and then evaluate those statements.  The success code is writting
** into *pRc.
**
** If *pRc is initially non-zero then this routine is a no-op.
*/
static void fts3DbExec(
  int *pRc,              /* Success code */
  sqlite3 *db,           /* Database in which to run SQL */

}


/*
** Invoke sqlite3_declare_vtab() to declare the schema for the FTS3 table
** passed as the first argument. This is done as part of the xConnect()
** and xCreate() methods.
**
** If *pRc is non-zero when this function is called, it is a no-op. 
** Otherwise, if an error occurs, an SQLite error code is stored in *pRc
** before returning.
*/
static void fts3DeclareVtab(int *pRc, Fts3Table *p){
static int fts3DeclareVtab(Fts3Table *p){
  if( *pRc==SQLITE_OK ){
    int i;                        /* Iterator variable */
    int rc;                       /* Return code */
    char *zSql;                   /* SQL statement passed to declare_vtab() */
    char *zCols;                  /* List of user defined columns */
  int i;                          /* Iterator variable */
  int rc;                         /* Return code */
  char *zSql;                     /* SQL statement passed to declare_vtab() */
  char *zCols;                    /* List of user defined columns */

    /* Create a list of user columns for the virtual table */
    zCols = sqlite3_mprintf("%Q, ", p->azColumn[0]);
    for(i=1; zCols && i<p->nColumn; i++){
      zCols = sqlite3_mprintf("%z%Q, ", zCols, p->azColumn[i]);
    }
  /* Create a list of user columns for the virtual table */
  zCols = sqlite3_mprintf("%Q, ", p->azColumn[0]);
  for(i=1; zCols && i<p->nColumn; i++){
    zCols = sqlite3_mprintf("%z%Q, ", zCols, p->azColumn[i]);
  }

    /* Create the whole "CREATE TABLE" statement to pass to SQLite */
    zSql = sqlite3_mprintf(
        "CREATE TABLE x(%s %Q HIDDEN, docid HIDDEN)", zCols, p->zName
    );
    if( !zCols || !zSql ){
      rc = SQLITE_NOMEM;
    }else{
      rc = sqlite3_declare_vtab(p->db, zSql);
    }
  /* Create the whole "CREATE TABLE" statement to pass to SQLite */
  zSql = sqlite3_mprintf(
      "CREATE TABLE x(%s %Q HIDDEN, docid HIDDEN)", zCols, p->zName
  );

  if( !zCols || !zSql ){
    rc = SQLITE_NOMEM;
  }else{
    rc = sqlite3_declare_vtab(p->db, zSql);
  }

    sqlite3_free(zSql);
    sqlite3_free(zCols);
    *pRc = rc;
  sqlite3_free(zSql);
  sqlite3_free(zCols);
  return rc;
  }
}

/*
** Create the backing store tables (%_content, %_segments and %_segdir)
** required by the FTS3 table passed as the only argument. This is done
** as part of the vtab xCreate() method.
**
** If the p->bHasDocsize boolean is true (indicating that this is an
** FTS4 table, not an FTS3 table) then also create the %_docsize and
** %_stat tables required by FTS4.
*/
static int fts3CreateTables(Fts3Table *p){
  int rc = SQLITE_OK;             /* Return code */
  int i;                          /* Iterator variable */
  char *zContentCols;             /* Columns of %_content table */
  sqlite3 *db = p->db;            /* The database connection */

  /* Create a list of user columns for the content table */
  if( p->bHasContent ){
  zContentCols = sqlite3_mprintf("docid INTEGER PRIMARY KEY");
  for(i=0; zContentCols && i<p->nColumn; i++){
    char *z = p->azColumn[i];
    zContentCols = sqlite3_mprintf("%z, 'c%d%q'", zContentCols, i, z);
  }
  if( zContentCols==0 ) rc = SQLITE_NOMEM;
    zContentCols = sqlite3_mprintf("docid INTEGER PRIMARY KEY");
    for(i=0; zContentCols && i<p->nColumn; i++){
      char *z = p->azColumn[i];
      zContentCols = sqlite3_mprintf("%z, 'c%d%q'", zContentCols, i, z);
    }
    if( zContentCols==0 ) rc = SQLITE_NOMEM;

  /* Create the content table */
  fts3DbExec(&rc, db, 
     "CREATE TABLE %Q.'%q_content'(%s)",
     p->zDb, p->zName, zContentCols
  );
  sqlite3_free(zContentCols);
    /* Create the content table */
    fts3DbExec(&rc, db, 
       "CREATE TABLE %Q.'%q_content'(%s)",
       p->zDb, p->zName, zContentCols
    );
    sqlite3_free(zContentCols);
  }
  /* Create other tables */
  fts3DbExec(&rc, db, 
      "CREATE TABLE %Q.'%q_segments'(blockid INTEGER PRIMARY KEY, block BLOB);",
      p->zDb, p->zName
  );
  fts3DbExec(&rc, db, 
      "CREATE TABLE %Q.'%q_segdir'("

      p->zDb, p->zName
  );
  if( p->bHasDocsize ){
    fts3DbExec(&rc, db, 
        "CREATE TABLE %Q.'%q_docsize'(docid INTEGER PRIMARY KEY, size BLOB);",
        p->zDb, p->zName
    );
  }
  if( p->bHasStat ){
    fts3DbExec(&rc, db, 
        "CREATE TABLE %Q.'%q_stat'(id INTEGER PRIMARY KEY, value BLOB);",
        p->zDb, p->zName
    );
  }
  return rc;
}

  );    
  rc = sqlite3_exec(db, zSql, fts3TableExistsCallback, &res, 0);
  sqlite3_free(zSql);
  *pResult = (u8)(res & 0xff);
  if( rc!=SQLITE_ABORT ) *pRc = rc;
}

/*
** Store the current database page-size in bytes in p->nPgsz.
**
** If *pRc is non-zero when this function is called, it is a no-op. 
** Otherwise, if an error occurs, an SQLite error code is stored in *pRc
** before returning.
*/
static void fts3DatabasePageSize(int *pRc, Fts3Table *p){
  if( *pRc==SQLITE_OK ){
    int rc;                       /* Return code */
    char *zSql;                   /* SQL text "PRAGMA %Q.page_size" */
    sqlite3_stmt *pStmt;          /* Compiled "PRAGMA %Q.page_size" statement */
  
    zSql = sqlite3_mprintf("PRAGMA %Q.page_size", p->zDb);
    if( !zSql ){
      rc = SQLITE_NOMEM;
    }else{
      rc = sqlite3_prepare(p->db, zSql, -1, &pStmt, 0);
      if( rc==SQLITE_OK ){
        sqlite3_step(pStmt);
        p->nPgsz = sqlite3_column_int(pStmt, 0);
        rc = sqlite3_finalize(pStmt);
      }
    }
    assert( p->nPgsz>0 || rc!=SQLITE_OK );
    sqlite3_free(zSql);
    *pRc = rc;
  }
}

/*
** "Special" FTS4 arguments are column specifications of the following form:
**
**   <key> = <value>
**
** There may not be whitespace surrounding the "=" character. The <value> 
** term may be quoted, but the <key> may not.
*/
static int fts3IsSpecialColumn(
  const char *z, 
  int *pnKey,
  char **pzValue
){
  char *zValue;
  const char *zCsr = z;

  while( *zCsr!='=' ){
    if( *zCsr=='\0' ) return 0;
    zCsr++;
  }

  *pnKey = zCsr-z;
  zValue = sqlite3_mprintf("%s", &zCsr[1]);
  if( zValue ){
    sqlite3Fts3Dequote(zValue);
  }
  *pzValue = zValue;
  return 1;
}

/*
** This function is the implementation of both the xConnect and xCreate
** methods of the FTS3 virtual table.
**
** The argv[] array contains the following:
**
**   argv[0]   -> module name  ("fts3" or "fts4")

  void *pAux,                     /* Hash table containing tokenizers */
  int argc,                       /* Number of elements in argv array */
  const char * const *argv,       /* xCreate/xConnect argument array */
  sqlite3_vtab **ppVTab,          /* Write the resulting vtab structure here */
  char **pzErr                    /* Write any error message here */
){
  Fts3Hash *pHash = (Fts3Hash *)pAux;
  Fts3Table *p = 0;               /* Pointer to allocated vtab */
  int rc = SQLITE_OK;             /* Return code */
  Fts3Table *p;                   /* Pointer to allocated vtab */
  int rc;                         /* Return code */
  int i;                          /* Iterator variable */
  int nByte;                      /* Size of allocation used for *p */
  int iCol;                       /* Column index */
  int nString = 0;                /* Bytes required to hold all column names */
  int nCol = 0;                   /* Number of columns in the FTS table */
  char *zCsr;                     /* Space for holding column names */
  int nDb;                        /* Bytes required to hold database name */
  int nName;                      /* Bytes required to hold table name */
  int isFts4 = (argv[0][3]=='4'); /* True for FTS4, false for FTS3 */
  int bNoDocsize = 0;             /* True to omit %_docsize table */

  const char *zTokenizer = 0;               /* Name of tokenizer to use */
  const char **aCol;              /* Array of column names */
  sqlite3_tokenizer *pTokenizer = 0;        /* Tokenizer for this table */

  assert( strlen(argv[0])==4 );
  assert( (sqlite3_strnicmp(argv[0], "fts4", 4)==0 && isFts4)
       || (sqlite3_strnicmp(argv[0], "fts3", 4)==0 && !isFts4)
  );

  nDb = (int)strlen(argv[1]) + 1;
  nName = (int)strlen(argv[2]) + 1;

  aCol = (const char **)sqlite3_malloc(sizeof(const char *) * (argc-2) );
  if( !aCol ) return SQLITE_NOMEM;
  memset(aCol, 0, sizeof(const char *) * (argc-2));

  /* Loop through all of the arguments passed by the user to the FTS3/4
  ** module (i.e. all the column names and special arguments). This loop
  ** does the following:
  **
  **   + Figures out the number of columns the FTSX table will have, and
  **     the number of bytes of space that must be allocated to store copies
  **     of the column names.
  **
  **   + If there is a tokenizer specification included in the arguments,
  **     initializes the tokenizer pTokenizer.
  */
  for(i=3; rc==SQLITE_OK && i<argc; i++){
  for(i=3; i<argc; i++){
    char const *z = argv[i];
    int nKey;
    char *zVal;

    /* Check if this is a tokenizer specification */
    if( !pTokenizer 
     && strlen(z)>8
     && 0==sqlite3_strnicmp(z, "tokenize", 8) 
     && 0==sqlite3Fts3IsIdChar(z[8])
    ){
      rc = sqlite3Fts3InitTokenizer(pHash, &z[9], &pTokenizer, pzErr);
    rc = sqlite3Fts3InitTokenizer(pHash, z, &pTokenizer, &zTokenizer, pzErr);
    }

    /* Check if it is an FTS4 special argument. */
    else if( isFts4 && fts3IsSpecialColumn(z, &nKey, &zVal) ){
      if( !zVal ){
        rc = SQLITE_NOMEM;
    if( rc!=SQLITE_OK ){
        goto fts3_init_out;
      }
      if( nKey==9 && 0==sqlite3_strnicmp(z, "matchinfo", 9) ){
        if( strlen(zVal)==4 && 0==sqlite3_strnicmp(zVal, "fts3", 4) ){
          bNoDocsize = 1;
        }else{
          *pzErr = sqlite3_mprintf("unrecognized matchinfo: %s", zVal);
          rc = SQLITE_ERROR;
        }
      return rc;
    }
      }else{
        *pzErr = sqlite3_mprintf("unrecognized parameter: %s", z);
        rc = SQLITE_ERROR;
      }
      sqlite3_free(zVal);
    }

    if( z!=zTokenizer ){
    /* Otherwise, the argument is a column name. */
    else {
      nString += (int)(strlen(z) + 1);
      aCol[nCol++] = z;
    }
  }
  if( rc!=SQLITE_OK ) goto fts3_init_out;

  if( nCol==0 ){
    assert( nString==0 );
    aCol[0] = "content";
    nString = 8;
    nCol = 1;
  nCol = argc - 3 - (zTokenizer!=0);
  }

  if( pTokenizer==0 ){
    rc = sqlite3Fts3InitTokenizer(pHash, "simple", &pTokenizer, pzErr);
    if( rc!=SQLITE_OK ) goto fts3_init_out;
  }
  assert( pTokenizer );

  if( zTokenizer==0 ){
    rc = sqlite3Fts3InitTokenizer(pHash, 0, &pTokenizer, 0, pzErr);
    if( rc!=SQLITE_OK ){
      return rc;
    }
    assert( pTokenizer );
  }

  if( nCol==0 ){
    nCol = 1;
  }

  /* Allocate and populate the Fts3Table structure. */
  nByte = sizeof(Fts3Table) +              /* Fts3Table */
          nCol * sizeof(char *) +              /* azColumn */
          nName +                              /* zName */
          nDb +                                /* zDb */
          nString;                             /* Space for azColumn strings */
  p = (Fts3Table*)sqlite3_malloc(nByte);
  if( p==0 ){
    rc = SQLITE_NOMEM;
    goto fts3_init_out;
  }
  memset(p, 0, nByte);

  p->db = db;
  p->nColumn = nCol;
  p->nPendingData = 0;
  p->azColumn = (char **)&p[1];
  p->pTokenizer = pTokenizer;
  p->nNodeSize = 1000;
  p->nMaxPendingData = FTS3_MAX_PENDING_DATA;
  p->bHasDocsize = (isFts4 && bNoDocsize==0);
  p->bHasStat = isFts4;
  zCsr = (char *)&p->azColumn[nCol];

  fts3HashInit(&p->pendingTerms, FTS3_HASH_STRING, 1);

  /* Fill in the zName and zDb fields of the vtab structure. */
  zCsr = (char *)&p->azColumn[nCol];
  p->zName = zCsr;
  memcpy(zCsr, argv[2], nName);
  zCsr += nName;
  p->zDb = zCsr;
  memcpy(zCsr, argv[1], nDb);
  zCsr += nDb;

  /* Fill in the azColumn array */
  for(iCol=0; iCol<nCol; iCol++){
    char *z; 
    int n;
    z = (char *)sqlite3Fts3NextToken(aCol[iCol], &n);
    memcpy(zCsr, z, n);
    zCsr[n] = '\0';
    sqlite3Fts3Dequote(zCsr);
    p->azColumn[iCol] = zCsr;
    zCsr += n+1;
    assert( zCsr <= &((char *)p)[nByte] );
  iCol = 0;
  for(i=3; i<argc; i++){
    if( argv[i]!=zTokenizer ){
      char *z; 
      int n;
      z = (char *)sqlite3Fts3NextToken(argv[i], &n);
      memcpy(zCsr, z, n);
      zCsr[n] = '\0';
      sqlite3Fts3Dequote(zCsr);
      p->azColumn[iCol++] = zCsr;
      zCsr += n+1;
      assert( zCsr <= &((char *)p)[nByte] );
    }
  }
  if( iCol==0 ){
    assert( nCol==1 );
    p->azColumn[0] = "content";
  }

  /* If this is an xCreate call, create the underlying tables in the 
  ** database. TODO: For xConnect(), it could verify that said tables exist.
  */
  if( isCreate ){
    p->bHasContent = 1;
    p->bHasDocsize = argv[0][3]=='4';
    rc = fts3CreateTables(p);
  }else{
    rc = SQLITE_OK;
    fts3TableExists(&rc, db, argv[1], argv[2], "_content", &p->bHasContent);
    fts3TableExists(&rc, db, argv[1], argv[2], "_docsize", &p->bHasDocsize);
  }
  if( rc!=SQLITE_OK ) goto fts3_init_out;

  /* Figure out the page-size for the database. This is required in order to
  ** estimate the cost of loading large doclists from the database (see 
  ** function sqlite3Fts3SegReaderCost() for details).
  */
  fts3DatabasePageSize(&rc, p);
  rc = fts3DeclareVtab(p);
  if( rc!=SQLITE_OK ) goto fts3_init_out;

  /* Declare the table schema to SQLite. */
  fts3DeclareVtab(&rc, p);
  *ppVTab = &p->base;

fts3_init_out:

  assert( p || (pTokenizer && rc!=SQLITE_OK) );
  sqlite3_free(aCol);
  if( rc!=SQLITE_OK ){
    if( p ){
      fts3DisconnectMethod((sqlite3_vtab *)p);
    }else if( pTokenizer ){
    }else{
      pTokenizer->pModule->xDestroy(pTokenizer);
    }
  }else{
    *ppVTab = &p->base;
  }
  return rc;
}

/*
** The xConnect() and xCreate() methods for the virtual table. All the
** work is done in function fts3InitVtab().

  return SQLITE_OK;
}

/*
** Close the cursor.  For additional information see the documentation
** on the xClose method of the virtual table interface.
*/
static int fts3CloseMethod(sqlite3_vtab_cursor *pCursor){
static int fulltextClose(sqlite3_vtab_cursor *pCursor){
  Fts3Cursor *pCsr = (Fts3Cursor *)pCursor;
  assert( ((Fts3Table *)pCsr->base.pVtab)->pSegments==0 );
  sqlite3_finalize(pCsr->pStmt);
  sqlite3Fts3ExprFree(pCsr->pExpr);
  sqlite3Fts3FreeDeferredTokens(pCsr);
  sqlite3_free(pCsr->aDoclist);
  sqlite3_free(pCsr->aMatchinfo);
  sqlite3_free(pCsr);
  return SQLITE_OK;
}

/*

    }
  }else{
    return SQLITE_OK;
  }
}

/*
** This function is used to process a single interior node when searching
** a b-tree for a term or term prefix. The node data is passed to this 
** function via the zNode/nNode parameters. The term to search for is
** passed in zTerm/nTerm.
** Advance the cursor to the next row in the %_content table that
** matches the search criteria.  For a MATCH search, this will be
** the next row that matches.  For a full-table scan, this will be
** simply the next row in the %_content table.  For a docid lookup,
**
** If piFirst is not NULL, then this function sets *piFirst to the blockid
** of the child node that heads the sub-tree that may contain the term.
**
** If piLast is not NULL, then *piLast is set to the right-most child node
** that heads a sub-tree that may contain a term for which zTerm/nTerm is
** a prefix.
** this routine simply sets the EOF flag.
**
** If an OOM error occurs, SQLITE_NOMEM is returned. Otherwise, SQLITE_OK.
** Return SQLITE_OK if nothing goes wrong.  SQLITE_OK is returned
** even if we reach end-of-file.  The fts3EofMethod() will be called
** subsequently to determine whether or not an EOF was hit.
*/
static int fts3ScanInteriorNode(
static int fts3NextMethod(sqlite3_vtab_cursor *pCursor){
  Fts3Table *p,                   /* Virtual table handle */
  const char *zTerm,              /* Term to select leaves for */
  int nTerm,                      /* Size of term zTerm in bytes */
  const char *zNode,              /* Buffer containing segment interior node */
  int nNode,                      /* Size of buffer at zNode */
  sqlite3_int64 *piFirst,         /* OUT: Selected child node */
  sqlite3_int64 *piLast           /* OUT: Selected child node */
){
  int rc = SQLITE_OK;             /* Return code */
  const char *zCsr = zNode;       /* Cursor to iterate through node */
  const char *zEnd = &zCsr[nNode];/* End of interior node buffer */
  char *zBuffer = 0;              /* Buffer to load terms into */
  int nAlloc = 0;                 /* Size of allocated buffer */
  int isFirstTerm = 1;            /* True when processing first term on page */
  sqlite3_int64 iChild;           /* Block id of child node to descend to */

  Fts3Cursor *pCsr = (Fts3Cursor *)pCursor;
  /* Skip over the 'height' varint that occurs at the start of every 
  ** interior node. Then load the blockid of the left-child of the b-tree
  ** node into variable iChild.  
  **
  ** Even if the data structure on disk is corrupted, this (reading two
  ** varints from the buffer) does not risk an overread. If zNode is a
  ** root node, then the buffer comes from a SELECT statement. SQLite does
  ** not make this guarantee explicitly, but in practice there are always
  ** either more than 20 bytes of allocated space following the nNode bytes of
  ** contents, or two zero bytes. Or, if the node is read from the %_segments
  ** table, then there are always 20 bytes of zeroed padding following the
  ** nNode bytes of content (see sqlite3Fts3ReadBlock() for details).
  */
  zCsr += sqlite3Fts3GetVarint(zCsr, &iChild);
  zCsr += sqlite3Fts3GetVarint(zCsr, &iChild);
  if( zCsr>=zEnd ){
    return SQLITE_CORRUPT;
  }
  

  if( pCsr->aDoclist==0 ){
  while( zCsr<zEnd && (piFirst || piLast) ){
    int cmp;                      /* memcmp() result */
    int nSuffix;                  /* Size of term suffix */
    int nPrefix = 0;              /* Size of term prefix */
    int nBuffer;                  /* Total term size */
  
    if( SQLITE_ROW!=sqlite3_step(pCsr->pStmt) ){
    /* Load the next term on the node into zBuffer. Use realloc() to expand
    ** the size of zBuffer if required.  */
    if( !isFirstTerm ){
      zCsr += sqlite3Fts3GetVarint32(zCsr, &nPrefix);
    }
    isFirstTerm = 0;
    zCsr += sqlite3Fts3GetVarint32(zCsr, &nSuffix);
    
      pCsr->isEof = 1;
    if( nPrefix<0 || nSuffix<0 || &zCsr[nSuffix]>zEnd ){
      rc = SQLITE_CORRUPT;
      rc = sqlite3_reset(pCsr->pStmt);
      goto finish_scan;
    }
    if( nPrefix+nSuffix>nAlloc ){
      char *zNew;
      nAlloc = (nPrefix+nSuffix) * 2;
      zNew = (char *)sqlite3_realloc(zBuffer, nAlloc);
      if( !zNew ){
        rc = SQLITE_NOMEM;
        goto finish_scan;
      }
      zBuffer = zNew;
    }
    memcpy(&zBuffer[nPrefix], zCsr, nSuffix);
    nBuffer = nPrefix + nSuffix;
    zCsr += nSuffix;

  }else if( pCsr->pNextId>=&pCsr->aDoclist[pCsr->nDoclist] ){
    /* Compare the term we are searching for with the term just loaded from
    ** the interior node. If the specified term is greater than or equal
    ** to the term from the interior node, then all terms on the sub-tree 
    ** headed by node iChild are smaller than zTerm. No need to search 
    ** iChild.
    **
    ** If the interior node term is larger than the specified term, then
    ** the tree headed by iChild may contain the specified term.
    */
    cmp = memcmp(zTerm, zBuffer, (nBuffer>nTerm ? nTerm : nBuffer));
    if( piFirst && (cmp<0 || (cmp==0 && nBuffer>nTerm)) ){
      *piFirst = iChild;
      piFirst = 0;
    }

    pCsr->isEof = 1;
  }else{
    sqlite3_reset(pCsr->pStmt);
    if( piLast && cmp<0 ){
      *piLast = iChild;
      piLast = 0;
    }

    fts3GetDeltaVarint(&pCsr->pNextId, &pCsr->iPrevId);
    iChild++;
  };

  if( piFirst ) *piFirst = iChild;
    pCsr->isRequireSeek = 1;
    pCsr->isMatchinfoNeeded = 1;
  if( piLast ) *piLast = iChild;

  }
 finish_scan:
  sqlite3_free(zBuffer);
  return rc;
}


/*
** The buffer pointed to by argument zNode (size nNode bytes) contains an
** interior node of a b-tree segment. The zTerm buffer (size nTerm bytes)
** contains a term. This function searches the sub-tree headed by the zNode
** node for the range of leaf nodes that may contain the specified term
** or terms for which the specified term is a prefix.
**
** The buffer pointed to by argument zNode (size nNode bytes) contains the
** root node of a b-tree segment. The segment is guaranteed to be at least
** one level high (i.e. the root node is not also a leaf). If successful,
** this function locates the leaf node of the segment that may contain the 
** term specified by arguments zTerm and nTerm and writes its block number 
** to *piLeaf.
** If piLeaf is not NULL, then *piLeaf is set to the blockid of the 
** left-most leaf node in the tree that may contain the specified term.
** If piLeaf2 is not NULL, then *piLeaf2 is set to the blockid of the
** right-most leaf node that may contain a term for which the specified
** term is a prefix.
**
** It is possible that the range of returned leaf nodes does not contain 
** It is possible that the returned leaf node does not contain the specified
** the specified term or any terms for which it is a prefix. However, if the 
** segment does contain any such terms, they are stored within the identified
** range. Because this function only inspects interior segment nodes (and
** never loads leaf nodes into memory), it is not possible to be sure.
** term. However, if the segment does contain said term, it is stored on
** the identified leaf node. Because this function only inspects interior
** segment nodes (and never loads leaf nodes into memory), it is not possible
** to be sure.
**
** If an error occurs, an error code other than SQLITE_OK is returned.
*/ 
static int fts3SelectLeaf(
  Fts3Table *p,                   /* Virtual table handle */
  const char *zTerm,              /* Term to select leaves for */
  int nTerm,                      /* Size of term zTerm in bytes */
  const char *zNode,              /* Buffer containing segment interior node */
  int nNode,                      /* Size of buffer at zNode */
  sqlite3_int64 *piLeaf,          /* Selected leaf node */
  sqlite3_int64 *piLeaf           /* Selected leaf node */
  sqlite3_int64 *piLeaf2          /* Selected leaf node */
){
  int rc;                         /* Return code */
  int iHeight;                    /* Height of this node in tree */
  int rc = SQLITE_OK;             /* Return code */
  const char *zCsr = zNode;       /* Cursor to iterate through node */
  const char *zEnd = &zCsr[nNode];/* End of interior node buffer */
  char *zBuffer = 0;              /* Buffer to load terms into */
  int nAlloc = 0;                 /* Size of allocated buffer */

  assert( piLeaf || piLeaf2 );
  while( 1 ){
    int isFirstTerm = 1;          /* True when processing first term on page */
    int iHeight;                  /* Height of this node in tree */
    sqlite3_int64 iChild;         /* Block id of child node to descend to */
    int nBlock;                   /* Size of child node in bytes */

  sqlite3Fts3GetVarint32(zNode, &iHeight);
    zCsr += sqlite3Fts3GetVarint32(zCsr, &iHeight);
  rc = fts3ScanInteriorNode(p, zTerm, nTerm, zNode, nNode, piLeaf, piLeaf2);
  assert( !piLeaf2 || !piLeaf || rc!=SQLITE_OK || (*piLeaf<=*piLeaf2) );

    zCsr += sqlite3Fts3GetVarint(zCsr, &iChild);
  
  if( rc==SQLITE_OK && iHeight>1 ){
    char *zBlob = 0;              /* Blob read from %_segments table */
    int nBlob;                    /* Size of zBlob in bytes */

    if( piLeaf && piLeaf2 && (*piLeaf!=*piLeaf2) ){
      rc = sqlite3Fts3ReadBlock(p, *piLeaf, &zBlob, &nBlob);
      if( rc==SQLITE_OK ){
    while( zCsr<zEnd ){
      int cmp;                    /* memcmp() result */
      int nSuffix;                /* Size of term suffix */
      int nPrefix = 0;            /* Size of term prefix */
      int nBuffer;                /* Total term size */
  
      /* Load the next term on the node into zBuffer */
      if( !isFirstTerm ){
        zCsr += sqlite3Fts3GetVarint32(zCsr, &nPrefix);
      }
      isFirstTerm = 0;
      zCsr += sqlite3Fts3GetVarint32(zCsr, &nSuffix);
      if( nPrefix+nSuffix>nAlloc ){
        char *zNew;
        nAlloc = (nPrefix+nSuffix) * 2;
        zNew = (char *)sqlite3_realloc(zBuffer, nAlloc);
        if( !zNew ){
          sqlite3_free(zBuffer);
          return SQLITE_NOMEM;
        rc = fts3SelectLeaf(p, zTerm, nTerm, zBlob, nBlob, piLeaf, 0);
      }
        }
      sqlite3_free(zBlob);
      piLeaf = 0;
      zBlob = 0;
    }

    if( rc==SQLITE_OK ){
        zBuffer = zNew;
      }
      memcpy(&zBuffer[nPrefix], zCsr, nSuffix);
      nBuffer = nPrefix + nSuffix;
      zCsr += nSuffix;
  
      /* Compare the term we are searching for with the term just loaded from
      ** the interior node. If the specified term is greater than or equal
      ** to the term from the interior node, then all terms on the sub-tree 
      ** headed by node iChild are smaller than zTerm. No need to search 
      ** iChild.
      **
      ** If the interior node term is larger than the specified term, then
      ** the tree headed by iChild may contain the specified term.
      */
      cmp = memcmp(zTerm, zBuffer, (nBuffer>nTerm ? nTerm : nBuffer));
      if( cmp<0 || (cmp==0 && nBuffer>nTerm) ) break;
      rc = sqlite3Fts3ReadBlock(p, piLeaf ? *piLeaf : *piLeaf2, &zBlob, &nBlob);
    }
    if( rc==SQLITE_OK ){
      rc = fts3SelectLeaf(p, zTerm, nTerm, zBlob, nBlob, piLeaf, piLeaf2);
      iChild++;
    };

    /* If (iHeight==1), the children of this interior node are leaves. The
    ** specified term may be present on leaf node iChild.
    */
    if( iHeight==1 ){
      *piLeaf = iChild;
      break;
    }
    sqlite3_free(zBlob);
  }


    /* Descend to interior node iChild. */
    rc = sqlite3Fts3ReadBlock(p, iChild, &zCsr, &nBlock);
    if( rc!=SQLITE_OK ) break;
    zEnd = &zCsr[nBlock];
  }
  sqlite3_free(zBuffer);
  return rc;
}

/*
** This function is used to create delta-encoded serialized lists of FTS3 
** varints. Each call to this function appends a single varint to a list.
*/

  *pp = p;
  *pp1 = p1 + 1;
  *pp2 = p2 + 1;
}

/*
** nToken==1 searches for adjacent positions.
**
** This function is used to merge two position lists into one. When it is
** called, *pp1 and *pp2 must both point to position lists. A position-list is
** the part of a doclist that follows each document id. For example, if a row
** contains:
**
**     'a b c'|'x y z'|'a b b a'
**
** Then the position list for this row for token 'b' would consist of:
**
**     0x02 0x01 0x02 0x03 0x03 0x00
**
** When this function returns, both *pp1 and *pp2 are left pointing to the
** byte following the 0x00 terminator of their respective position lists.
**
** If isSaveLeft is 0, an entry is added to the output position list for 
** each position in *pp2 for which there exists one or more positions in
** *pp1 so that (pos(*pp2)>pos(*pp1) && pos(*pp2)-pos(*pp1)<=nToken). i.e.
** when the *pp1 token appears before the *pp2 token, but not more than nToken
** slots before it.
*/
static int fts3PoslistPhraseMerge(
  char **pp,                      /* IN/OUT: Preallocated output buffer */
  char **pp,                      /* Output buffer */
  int nToken,                     /* Maximum difference in token positions */
  int isSaveLeft,                 /* Save the left position */
  int isExact,                    /* If *pp1 is exactly nTokens before *pp2 */
  char **pp1,                     /* IN/OUT: Left input list */
  char **pp2                      /* IN/OUT: Right input list */
  char **pp1,                     /* Left input list */
  char **pp2                      /* Right input list */
){
  char *p = (pp ? *pp : 0);
  char *p1 = *pp1;
  char *p2 = *pp2;

  int iCol1 = 0;
  int iCol2 = 0;

  /* Never set both isSaveLeft and isExact for the same invocation. */
  assert( isSaveLeft==0 || isExact==0 );

  assert( *p1!=0 && *p2!=0 );
  if( *p1==POS_COLUMN ){ 
    p1++;
    p1 += sqlite3Fts3GetVarint32(p1, &iCol1);
  }
  if( *p2==POS_COLUMN ){ 
    p2++;

      assert( *p1!=POS_END && *p1!=POS_COLUMN );
      assert( *p2!=POS_END && *p2!=POS_COLUMN );
      fts3GetDeltaVarint(&p1, &iPos1); iPos1 -= 2;
      fts3GetDeltaVarint(&p2, &iPos2); iPos2 -= 2;

      while( 1 ){
        if( iPos2==iPos1+nToken 
         || (isExact==0 && iPos2>iPos1 && iPos2<=iPos1+nToken) 
        if( iPos2>iPos1 && iPos2<=iPos1+nToken ){
        ){
          sqlite3_int64 iSave;
          if( !pp ){
            fts3PoslistCopy(0, &p2);
            fts3PoslistCopy(0, &p1);
            *pp1 = p1;
            *pp2 = p2;
            return 1;

  char **pp1,                     /* IN/OUT: Left input list */
  char **pp2                      /* IN/OUT: Right input list */
){
  char *p1 = *pp1;
  char *p2 = *pp2;

  if( !pp ){
    if( fts3PoslistPhraseMerge(0, nRight, 0, 0, pp1, pp2) ) return 1;
    if( fts3PoslistPhraseMerge(0, nRight, 0, pp1, pp2) ) return 1;
    *pp1 = p1;
    *pp2 = p2;
    return fts3PoslistPhraseMerge(0, nLeft, 0, 0, pp2, pp1);
    return fts3PoslistPhraseMerge(0, nLeft, 0, pp2, pp1);
  }else{
    char *pTmp1 = aTmp;
    char *pTmp2;
    char *aTmp2;
    int res = 1;

    fts3PoslistPhraseMerge(&pTmp1, nRight, 0, 0, pp1, pp2);
    fts3PoslistPhraseMerge(&pTmp1, nRight, 0, pp1, pp2);
    aTmp2 = pTmp2 = pTmp1;
    *pp1 = p1;
    *pp2 = p2;
    fts3PoslistPhraseMerge(&pTmp2, nLeft, 1, 0, pp2, pp1);
    fts3PoslistPhraseMerge(&pTmp2, nLeft, 1, pp2, pp1);
    if( pTmp1!=aTmp && pTmp2!=aTmp2 ){
      fts3PoslistMerge(pp, &aTmp, &aTmp2);
    }else if( pTmp1!=aTmp ){
      fts3PoslistCopy(pp, &aTmp);
    }else if( pTmp2!=aTmp2 ){
      fts3PoslistCopy(pp, &aTmp2);
    }else{

  int nParam1,                    /* Used by MERGE_NEAR and MERGE_POS_NEAR */
  int nParam2,                    /* Used by MERGE_NEAR and MERGE_POS_NEAR */
  char *aBuffer,                  /* Pre-allocated output buffer */
  int *pnBuffer,                  /* OUT: Bytes written to aBuffer */
  char *a1,                       /* Buffer containing first doclist */
  int n1,                         /* Size of buffer a1 */
  char *a2,                       /* Buffer containing second doclist */
  int n2,                         /* Size of buffer a2 */
  int n2                          /* Size of buffer a2 */
  int *pnDoc                      /* OUT: Number of docids in output */
){
  sqlite3_int64 i1 = 0;
  sqlite3_int64 i2 = 0;
  sqlite3_int64 iPrev = 0;

  char *p = aBuffer;
  char *p1 = a1;
  char *p2 = a2;
  char *pEnd1 = &a1[n1];
  char *pEnd2 = &a2[n2];
  int nDoc = 0;

  assert( mergetype==MERGE_OR     || mergetype==MERGE_POS_OR 
       || mergetype==MERGE_AND    || mergetype==MERGE_NOT
       || mergetype==MERGE_PHRASE || mergetype==MERGE_POS_PHRASE
       || mergetype==MERGE_NEAR   || mergetype==MERGE_POS_NEAR
  );

    case MERGE_AND:
      while( p1 && p2 ){
        if( i1==i2 ){
          fts3PutDeltaVarint(&p, &iPrev, i1);
          fts3GetDeltaVarint2(&p1, pEnd1, &i1);
          fts3GetDeltaVarint2(&p2, pEnd2, &i2);
          nDoc++;
        }else if( i1<i2 ){
          fts3GetDeltaVarint2(&p1, pEnd1, &i1);
        }else{
          fts3GetDeltaVarint2(&p2, pEnd2, &i2);
        }
      }
      break;

    case MERGE_PHRASE: {
      char **ppPos = (mergetype==MERGE_PHRASE ? 0 : &p);
      while( p1 && p2 ){
        if( i1==i2 ){
          char *pSave = p;
          sqlite3_int64 iPrevSave = iPrev;
          fts3PutDeltaVarint(&p, &iPrev, i1);
          if( 0==fts3PoslistPhraseMerge(ppPos, nParam1, 0, 1, &p1, &p2) ){
          if( 0==fts3PoslistPhraseMerge(ppPos, 1, 0, &p1, &p2) ){
            p = pSave;
            iPrev = iPrevSave;
          }else{
            nDoc++;
          }
          fts3GetDeltaVarint2(&p1, pEnd1, &i1);
          fts3GetDeltaVarint2(&p2, pEnd2, &i2);
        }else if( i1<i2 ){
          fts3PoslistCopy(0, &p1);
          fts3GetDeltaVarint2(&p1, pEnd1, &i1);
        }else{

        }
      }
      sqlite3_free(aTmp);
      break;
    }
  }

  if( pnDoc ) *pnDoc = nDoc;
  *pnBuffer = (int)(p-aBuffer);
  return SQLITE_OK;
}

/* 
** A pointer to an instance of this structure is used as the context 
** argument to sqlite3Fts3SegReaderIterate()

  ** into a single doclist.
  */
  for(i=0; i<SizeofArray(pTS->aaOutput); i++){
    if( pTS->aaOutput[i] ){
      if( !aOut ){
        aOut = pTS->aaOutput[i];
        nOut = pTS->anOutput[i];
        pTS->aaOutput[i] = 0;
        pTS->aaOutput[0] = 0;
      }else{
        int nNew = nOut + pTS->anOutput[i];
        char *aNew = sqlite3_malloc(nNew);
        if( !aNew ){
          sqlite3_free(aOut);
          return SQLITE_NOMEM;
        }
        fts3DoclistMerge(mergetype, 0, 0,
            aNew, &nNew, pTS->aaOutput[i], pTS->anOutput[i], aOut, nOut, 0
            aNew, &nNew, pTS->aaOutput[i], pTS->anOutput[i], aOut, nOut
        );
        sqlite3_free(pTS->aaOutput[i]);
        sqlite3_free(aOut);
        pTS->aaOutput[i] = 0;
        aOut = aNew;
        nOut = nNew;
      }

      aNew = sqlite3_malloc(nNew);
      if( !aNew ){
        if( aMerge!=aDoclist ){
          sqlite3_free(aMerge);
        }
        return SQLITE_NOMEM;
      }
      fts3DoclistMerge(mergetype, 0, 0, aNew, &nNew, 
          pTS->aaOutput[iOut], pTS->anOutput[iOut], aMerge, nMerge, 0
      fts3DoclistMerge(mergetype, 0, 0,
          aNew, &nNew, pTS->aaOutput[iOut], pTS->anOutput[iOut], aMerge, nMerge
      );

      if( iOut>0 ) sqlite3_free(aMerge);
      sqlite3_free(pTS->aaOutput[iOut]);
      pTS->aaOutput[iOut] = 0;

      aMerge = aNew;
      nMerge = nNew;
      if( (iOut+1)==SizeofArray(pTS->aaOutput) ){
        pTS->aaOutput[iOut] = aMerge;
        pTS->anOutput[iOut] = nMerge;
      }
    }
  }
  return SQLITE_OK;
}

static int fts3DeferredTermSelect(
  Fts3DeferredToken *pToken,      /* Phrase token */
  int isTermPos,                  /* True to include positions */
  int *pnOut,                     /* OUT: Size of list */
  char **ppOut                    /* OUT: Body of list */
){
  char *aSource;
  int nSource;

  aSource = sqlite3Fts3DeferredDoclist(pToken, &nSource);
  if( !aSource ){
    *pnOut = 0;
    *ppOut = 0;
  }else if( isTermPos ){
    *ppOut = sqlite3_malloc(nSource);
    if( !*ppOut ) return SQLITE_NOMEM;
    memcpy(*ppOut, aSource, nSource);
    *pnOut = nSource;
  }else{
    sqlite3_int64 docid;
    *pnOut = sqlite3Fts3GetVarint(aSource, &docid);
    *ppOut = sqlite3_malloc(*pnOut);
    if( !*ppOut ) return SQLITE_NOMEM;
    sqlite3Fts3PutVarint(*ppOut, docid);
  }

  return SQLITE_OK;
}

/*
** An Fts3SegReaderArray is used to store an array of Fts3SegReader objects.
** Elements are added to the array using fts3SegReaderArrayAdd(). 
*/
struct Fts3SegReaderArray {
  int nSegment;                   /* Number of valid entries in apSegment[] */
  int nAlloc;                     /* Allocated size of apSegment[] */
  int nCost;                      /* The cost of executing SegReaderIterate() */
  Fts3SegReader *apSegment[1];    /* Array of seg-reader objects */
};


/*
** Free an Fts3SegReaderArray object. Also free all seg-readers in the
** array (using sqlite3Fts3SegReaderFree()).
*/
static void fts3SegReaderArrayFree(Fts3SegReaderArray *pArray){
  if( pArray ){
    int i;
    for(i=0; i<pArray->nSegment; i++){
      sqlite3Fts3SegReaderFree(0, pArray->apSegment[i]);
    }
    sqlite3_free(pArray);
  }
}

static int fts3SegReaderArrayAdd(
  Fts3SegReaderArray **ppArray, 
  Fts3SegReader *pNew
){
  Fts3SegReaderArray *pArray = *ppArray;

  if( !pArray || pArray->nAlloc==pArray->nSegment ){
    int nNew = (pArray ? pArray->nAlloc+16 : 16);
    pArray = (Fts3SegReaderArray *)sqlite3_realloc(pArray, 
        sizeof(Fts3SegReaderArray) + (nNew-1) * sizeof(Fts3SegReader*)
    );
    if( !pArray ){
      sqlite3Fts3SegReaderFree(0, pNew);
      return SQLITE_NOMEM;
    }
    if( nNew==16 ){
      pArray->nSegment = 0;
      pArray->nCost = 0;
    }
    pArray->nAlloc = nNew;
    *ppArray = pArray;
  }

  pArray->apSegment[pArray->nSegment++] = pNew;
  return SQLITE_OK;
}

static int fts3TermSegReaderArray(
  Fts3Cursor *pCsr,               /* Virtual table cursor handle */
  const char *zTerm,              /* Term to query for */
  int nTerm,                      /* Size of zTerm in bytes */
  int isPrefix,                   /* True for a prefix search */
  Fts3SegReaderArray **ppArray    /* OUT: Allocated seg-reader array */
){
  Fts3Table *p = (Fts3Table *)pCsr->base.pVtab;
  int rc;                         /* Return code */
  Fts3SegReaderArray *pArray = 0; /* Array object to build */
  Fts3SegReader *pReader = 0;     /* Seg-reader to add to pArray */ 
  sqlite3_stmt *pStmt = 0;        /* SQL statement to scan %_segdir table */
  int iAge = 0;                   /* Used to assign ages to segments */

  /* Allocate a seg-reader to scan the pending terms, if any. */
  rc = sqlite3Fts3SegReaderPending(p, zTerm, nTerm, isPrefix, &pReader);
  if( rc==SQLITE_OK && pReader ) {
    rc = fts3SegReaderArrayAdd(&pArray, pReader);
  }

  /* Loop through the entire %_segdir table. For each segment, create a
  ** Fts3SegReader to iterate through the subset of the segment leaves
  ** that may contain a term that matches zTerm/nTerm. For non-prefix
  ** searches, this is always a single leaf. For prefix searches, this
  ** may be a contiguous block of leaves.
  */
  if( rc==SQLITE_OK ){
    rc = sqlite3Fts3AllSegdirs(p, &pStmt);
  }
  while( rc==SQLITE_OK && SQLITE_ROW==(rc = sqlite3_step(pStmt)) ){
    Fts3SegReader *pNew = 0;
    int nRoot = sqlite3_column_bytes(pStmt, 4);
    char const *zRoot = sqlite3_column_blob(pStmt, 4);
    if( sqlite3_column_int64(pStmt, 1)==0 ){
      /* The entire segment is stored on the root node (which must be a
      ** leaf). Do not bother inspecting any data in this case, just
      ** create a Fts3SegReader to scan the single leaf. 
      */
      rc = sqlite3Fts3SegReaderNew(p, iAge, 0, 0, 0, zRoot, nRoot, &pNew);
    }else{
      sqlite3_int64 i1;           /* First leaf that may contain zTerm */
      sqlite3_int64 i2;           /* Final leaf that may contain zTerm */
      rc = fts3SelectLeaf(p, zTerm, nTerm, zRoot, nRoot, &i1, (isPrefix?&i2:0));
      if( isPrefix==0 ) i2 = i1;
      if( rc==SQLITE_OK ){
        rc = sqlite3Fts3SegReaderNew(p, iAge, i1, i2, 0, 0, 0, &pNew);
      }
    }
    assert( (pNew==0)==(rc!=SQLITE_OK) );

    /* If a new Fts3SegReader was allocated, add it to the array. */
    if( rc==SQLITE_OK ){
      rc = fts3SegReaderArrayAdd(&pArray, pNew);
    }
    if( rc==SQLITE_OK ){
      rc = sqlite3Fts3SegReaderCost(pCsr, pNew, &pArray->nCost);
    }
    iAge++;
  }

  if( rc==SQLITE_DONE ){
    rc = sqlite3_reset(pStmt);
  }else{
    sqlite3_reset(pStmt);
  }
  if( rc!=SQLITE_OK ){
    fts3SegReaderArrayFree(pArray);
    pArray = 0;
  }
  *ppArray = pArray;
  return rc;
}

/*
** This function retreives the doclist for the specified term (or term
** prefix) from the database. 
**
** The returned doclist may be in one of two formats, depending on the 
** value of parameter isReqPos. If isReqPos is zero, then the doclist is
** a sorted list of delta-compressed docids (a bare doclist). If isReqPos
** is non-zero, then the returned list is in the same format as is stored 
** in the database without the found length specifier at the start of on-disk
** doclists.
*/
static int fts3TermSelect(
  Fts3Table *p,                   /* Virtual table handle */
  Fts3PhraseToken *pTok,          /* Token to query for */
  int iColumn,                    /* Column to query (or -ve for all columns) */
  const char *zTerm,              /* Term to query for */
  int nTerm,                      /* Size of zTerm in bytes */
  int isPrefix,                   /* True for a prefix search */
  int isReqPos,                   /* True to include position lists in output */
  int *pnOut,                     /* OUT: Size of buffer at *ppOut */
  char **ppOut                    /* OUT: Malloced result buffer */
){
  int i;
  TermSelect tsc;
  Fts3SegFilter filter;           /* Segment term filter configuration */
  Fts3SegReader **apSegment;      /* Array of segments to read data from */
  int nSegment = 0;               /* Size of apSegment array */
  int nAlloc = 16;                /* Allocated size of segment array */
  int rc;                         /* Return code */
  sqlite3_stmt *pStmt = 0;        /* SQL statement to scan %_segdir table */
  int iAge = 0;                   /* Used to assign ages to segments */

  apSegment = (Fts3SegReader **)sqlite3_malloc(sizeof(Fts3SegReader*)*nAlloc);
  if( !apSegment ) return SQLITE_NOMEM;
  rc = sqlite3Fts3SegReaderPending(p, zTerm, nTerm, isPrefix, &apSegment[0]);
  if( rc!=SQLITE_OK ) goto finished;
  if( apSegment[0] ){
    nSegment = 1;
  }

  /* Loop through the entire %_segdir table. For each segment, create a
  ** Fts3SegReader to iterate through the subset of the segment leaves
  ** that may contain a term that matches zTerm/nTerm. For non-prefix
  ** searches, this is always a single leaf. For prefix searches, this
  ** may be a contiguous block of leaves.
  **
  ** The code in this loop does not actually load any leaves into memory
  ** (unless the root node happens to be a leaf). It simply examines the
  ** b-tree structure to determine which leaves need to be inspected.
  */
  rc = sqlite3Fts3AllSegdirs(p, &pStmt);
  while( rc==SQLITE_OK && SQLITE_ROW==(rc = sqlite3_step(pStmt)) ){
  Fts3SegReaderArray *pArray;     /* Seg-reader array for this term */
  TermSelect tsc;               /* Context object for fts3TermSelectCb() */
  Fts3SegFilter filter;         /* Segment term filter configuration */

  pArray = pTok->pArray;
    Fts3SegReader *pNew = 0;
    int nRoot = sqlite3_column_bytes(pStmt, 4);
    char const *zRoot = sqlite3_column_blob(pStmt, 4);
    if( sqlite3_column_int64(pStmt, 1)==0 ){
      /* The entire segment is stored on the root node (which must be a
      ** leaf). Do not bother inspecting any data in this case, just
      ** create a Fts3SegReader to scan the single leaf. 
      */
      rc = sqlite3Fts3SegReaderNew(p, iAge, 0, 0, 0, zRoot, nRoot, &pNew);
    }else{
      int rc2;                    /* Return value of sqlite3Fts3ReadBlock() */
      sqlite3_int64 i1;           /* Blockid of leaf that may contain zTerm */
      rc = fts3SelectLeaf(p, zTerm, nTerm, zRoot, nRoot, &i1);
      if( rc==SQLITE_OK ){
        sqlite3_int64 i2 = sqlite3_column_int64(pStmt, 2);
        rc = sqlite3Fts3SegReaderNew(p, iAge, i1, i2, 0, 0, 0, &pNew);
      }

      /* The following call to ReadBlock() serves to reset the SQL statement
      ** used to retrieve blocks of data from the %_segments table. If it is
      ** not reset here, then it may remain classified as an active statement 
      ** by SQLite, which may lead to "DROP TABLE" or "DETACH" commands 
      ** failing.
      */ 
      rc2 = sqlite3Fts3ReadBlock(p, 0, 0, 0);
      if( rc==SQLITE_OK ){
        rc = rc2;
      }
    }
    iAge++;

    /* If a new Fts3SegReader was allocated, add it to the apSegment array. */
    assert( pNew!=0 || rc!=SQLITE_OK );
    if( pNew ){
      if( nSegment==nAlloc ){
        Fts3SegReader **pArray;
        nAlloc += 16;
        pArray = (Fts3SegReader **)sqlite3_realloc(
            apSegment, nAlloc*sizeof(Fts3SegReader *)
        );
        if( !pArray ){
          sqlite3Fts3SegReaderFree(p, pNew);
          rc = SQLITE_NOMEM;
          goto finished;
        }
        apSegment = pArray;
      }
      apSegment[nSegment++] = pNew;
    }
  }
  if( rc!=SQLITE_DONE ){
    assert( rc!=SQLITE_OK );
    goto finished;
  }

  memset(&tsc, 0, sizeof(TermSelect));
  tsc.isReqPos = isReqPos;

  filter.flags = FTS3_SEGMENT_IGNORE_EMPTY 
        | (pTok->isPrefix ? FTS3_SEGMENT_PREFIX : 0)
        | (isPrefix ? FTS3_SEGMENT_PREFIX : 0)
        | (isReqPos ? FTS3_SEGMENT_REQUIRE_POS : 0)
        | (iColumn<p->nColumn ? FTS3_SEGMENT_COLUMN_FILTER : 0);
  filter.iCol = iColumn;
  filter.zTerm = pTok->z;
  filter.nTerm = pTok->n;
  filter.zTerm = zTerm;
  filter.nTerm = nTerm;

  rc = sqlite3Fts3SegReaderIterate(p, pArray->apSegment, pArray->nSegment, 
      &filter, fts3TermSelectCb, (void *)&tsc
  rc = sqlite3Fts3SegReaderIterate(p, apSegment, nSegment, &filter,
      fts3TermSelectCb, (void *)&tsc
  );
  if( rc==SQLITE_OK ){
    rc = fts3TermSelectMerge(&tsc);
  }

  if( rc==SQLITE_OK ){
    *ppOut = tsc.aaOutput[0];
    *pnOut = tsc.anOutput[0];
  }else{
    int i;
    for(i=0; i<SizeofArray(tsc.aaOutput); i++){
      sqlite3_free(tsc.aaOutput[i]);
    }
  }

  fts3SegReaderArrayFree(pArray);
  pTok->pArray = 0;
  return rc;
}

finished:
/*
** This function counts the total number of docids in the doclist stored
** in buffer aList[], size nList bytes.
**
** If the isPoslist argument is true, then it is assumed that the doclist
** contains a position-list following each docid. Otherwise, it is assumed
** that the doclist is simply a list of docids stored as delta encoded 
** varints.
*/
static int fts3DoclistCountDocids(int isPoslist, char *aList, int nList){
  int nDoc = 0;                   /* Return value */
  if( aList ){
    char *aEnd = &aList[nList];   /* Pointer to one byte after EOF */
    char *p = aList;              /* Cursor */
    if( !isPoslist ){
      /* The number of docids in the list is the same as the number of 
      ** varints. In FTS3 a varint consists of a single byte with the 0x80 
      ** bit cleared and zero or more bytes with the 0x80 bit set. So to
      ** count the varints in the buffer, just count the number of bytes
      ** with the 0x80 bit clear.  */
      while( p<aEnd ) nDoc += (((*p++)&0x80)==0);
    }else{
      while( p<aEnd ){
        nDoc++;
        while( (*p++)&0x80 );     /* Skip docid varint */
        fts3PoslistCopy(0, &p);   /* Skip over position list */
      }
    }
  }

  sqlite3_reset(pStmt);
  return nDoc;
}

  for(i=0; i<nSegment; i++){
/*
** Call sqlite3Fts3DeferToken() for each token in the expression pExpr.
    sqlite3Fts3SegReaderFree(p, apSegment[i]);
*/
static int fts3DeferExpression(Fts3Cursor *pCsr, Fts3Expr *pExpr){
  int rc = SQLITE_OK;
  if( pExpr ){
    rc = fts3DeferExpression(pCsr, pExpr->pLeft);
    if( rc==SQLITE_OK ){
      rc = fts3DeferExpression(pCsr, pExpr->pRight);
    }
  }
    if( pExpr->eType==FTSQUERY_PHRASE ){
      int iCol = pExpr->pPhrase->iColumn;
      int i;
      for(i=0; rc==SQLITE_OK && i<pExpr->pPhrase->nToken; i++){
        Fts3PhraseToken *pToken = &pExpr->pPhrase->aToken[i];
        if( pToken->pDeferred==0 ){
          rc = sqlite3Fts3DeferToken(pCsr, pToken, iCol);
  sqlite3_free(apSegment);
        }
      }
    }
  }
  return rc;
}

/*
** This function removes the position information from a doclist. When
** called, buffer aList (size *pnList bytes) contains a doclist that includes
** position information. This function removes the position information so
** that aList contains only docids, and adjusts *pnList to reflect the new
** (possibly reduced) size of the doclist.
*/
static void fts3DoclistStripPositions(
  char *aList,                    /* IN/OUT: Buffer containing doclist */
  int *pnList                     /* IN/OUT: Size of doclist in bytes */
){
  if( aList ){
    char *aEnd = &aList[*pnList]; /* Pointer to one byte after EOF */
    char *p = aList;              /* Input cursor */
    char *pOut = aList;           /* Output cursor */
  

    while( p<aEnd ){
      sqlite3_int64 delta;
      p += sqlite3Fts3GetVarint(p, &delta);
      fts3PoslistCopy(0, &p);
      pOut += sqlite3Fts3PutVarint(pOut, delta);
    }

    *pnList = (pOut - aList);
  }
}

/* 
** Return a DocList corresponding to the phrase *pPhrase.
**
** If this function returns SQLITE_OK, but *pnOut is set to a negative value,
** then no tokens in the phrase were looked up in the full-text index. This
** is only possible when this function is called from within xFilter(). The
** caller should assume that all documents match the phrase. The actual
** filtering will take place in xNext().
*/
static int fts3PhraseSelect(
  Fts3Cursor *pCsr,               /* Virtual table cursor handle */
  Fts3Table *p,                   /* Virtual table handle */
  Fts3Phrase *pPhrase,            /* Phrase to return a doclist for */
  int isReqPos,                   /* True if output should contain positions */
  char **paOut,                   /* OUT: Pointer to malloc'd result buffer */
  int *pnOut                      /* OUT: Size of buffer at *paOut */
){
  char *pOut = 0;
  int nOut = 0;
  int rc = SQLITE_OK;
  int ii;
  int iCol = pPhrase->iColumn;
  int isTermPos = (pPhrase->nToken>1 || isReqPos);
  Fts3Table *p = (Fts3Table *)pCsr->base.pVtab;
  int isFirst = 1;

  int iPrevTok = 0;
  int nDoc = 0;

  /* If this is an xFilter() evaluation, create a segment-reader for each
  ** phrase token. Or, if this is an xNext() or snippet/offsets/matchinfo
  ** evaluation, only create segment-readers if there are no Fts3DeferredToken
  ** objects attached to the phrase-tokens.
  */
  for(ii=0; ii<pPhrase->nToken; ii++){
    Fts3PhraseToken *pTok = &pPhrase->aToken[ii];
    if( pTok->pArray==0 ){
    struct PhraseToken *pTok = &pPhrase->aToken[ii];
    char *z = pTok->z;            /* Next token of the phrase */
      if( (pCsr->eEvalmode==FTS3_EVAL_FILTER)
       || (pCsr->eEvalmode==FTS3_EVAL_NEXT && pCsr->pDeferred==0) 
       || (pCsr->eEvalmode==FTS3_EVAL_MATCHINFO && pTok->bFulltext) 
      ){
        rc = fts3TermSegReaderArray(
            pCsr, pTok->z, pTok->n, pTok->isPrefix, &pTok->pArray
    int n = pTok->n;              /* Size of z in bytes */
        );
        if( rc!=SQLITE_OK ) return rc;
      }
    }
  }

    int isPrefix = pTok->isPrefix;/* True if token is a prefix */
  for(ii=0; ii<pPhrase->nToken; ii++){
    Fts3PhraseToken *pTok;        /* Token to find doclist for */
    int iTok;                     /* The token being queried this iteration */
    char *pList;                  /* Pointer to token doclist */
    int nList;                    /* Size of buffer at pList */

    /* Select a token to process. If this is an xFilter() call, then tokens 
    ** are processed in order from least to most costly. Otherwise, tokens 
    ** are processed in the order in which they occur in the phrase.
    */
    if( pCsr->eEvalmode==FTS3_EVAL_MATCHINFO ){
      assert( isReqPos );
      iTok = ii;
      pTok = &pPhrase->aToken[iTok];
      if( pTok->bFulltext==0 ) continue;
    }else if( pCsr->eEvalmode==FTS3_EVAL_NEXT || isReqPos ){
      iTok = ii;
      pTok = &pPhrase->aToken[iTok];
    }else{
      int nMinCost = 0x7FFFFFFF;
      int jj;

      /* Find the remaining token with the lowest cost. */
      for(jj=0; jj<pPhrase->nToken; jj++){
        Fts3SegReaderArray *pArray = pPhrase->aToken[jj].pArray;
        if( pArray && pArray->nCost<nMinCost ){
          iTok = jj;
          nMinCost = pArray->nCost;
        }
      }
      pTok = &pPhrase->aToken[iTok];

      /* This branch is taken if it is determined that loading the doclist
      ** for the next token would require more IO than loading all documents
      ** currently identified by doclist pOut/nOut. No further doclists will
      ** be loaded from the full-text index for this phrase.
      */
      if( nMinCost>nDoc && ii>0 ){
        rc = fts3DeferExpression(pCsr, pCsr->pExpr);
        break;
      }
    }

    if( pCsr->eEvalmode==FTS3_EVAL_NEXT && pTok->pDeferred ){
      rc = fts3DeferredTermSelect(pTok->pDeferred, isTermPos, &nList, &pList);
    }else{
      assert( pTok->pArray );
      rc = fts3TermSelect(p, pTok, iCol, isTermPos, &nList, &pList);
    rc = fts3TermSelect(p, iCol, z, n, isPrefix, isTermPos, &nList, &pList);
      pTok->bFulltext = 1;
    }
    assert( rc!=SQLITE_OK || pCsr->eEvalmode || pTok->pArray==0 );
    if( rc!=SQLITE_OK ) break;

    if( isFirst ){
    if( ii==0 ){
      pOut = pList;
      nOut = nList;
      if( pCsr->eEvalmode==FTS3_EVAL_FILTER && pPhrase->nToken>1 ){
        nDoc = fts3DoclistCountDocids(1, pOut, nOut);
      }
      isFirst = 0;
      iPrevTok = iTok;
    }else{
      /* Merge the new term list and the current output. */
      /* Merge the new term list and the current output. If this is the
      char *aLeft, *aRight;
      int nLeft, nRight;
      int nDist;
      int mt;

      /* If this is the final token of the phrase, and positions were not
      ** last term in the phrase, and positions are not required in the
      ** output of this function, the positions can be dropped as part
      ** requested by the caller, use MERGE_PHRASE instead of POS_PHRASE.
      ** This drops the position information from the output list.
      ** of this merge. Either way, the result of this merge will be
      ** smaller than nList bytes. The code in fts3DoclistMerge() is written
      ** so that it is safe to use pList as the output as well as an input
      ** in this case.
      */
      mt = MERGE_POS_PHRASE;
      if( ii==pPhrase->nToken-1 && !isReqPos ) mt = MERGE_PHRASE;

      int mergetype = MERGE_POS_PHRASE;
      if( ii==pPhrase->nToken-1 && !isReqPos ){
        mergetype = MERGE_PHRASE;
      assert( iPrevTok!=iTok );
      if( iPrevTok<iTok ){
        aLeft = pOut;
        nLeft = nOut;
        aRight = pList;
        nRight = nList;
        nDist = iTok-iPrevTok;
        iPrevTok = iTok;
      }else{
        aRight = pOut;
        nRight = nOut;
        aLeft = pList;
        nLeft = nList;
        nDist = iPrevTok-iTok;
      }
      pOut = aRight;
      fts3DoclistMerge(
      fts3DoclistMerge(mergetype, 0, 0, pList, &nOut, pOut, nOut, pList, nList);
          mt, nDist, 0, pOut, &nOut, aLeft, nLeft, aRight, nRight, &nDoc
      );
      sqlite3_free(aLeft);
      sqlite3_free(pOut);
      pOut = pList;
    }
    assert( nOut==0 || pOut!=0 );
  }

  if( rc==SQLITE_OK ){
    if( ii!=pPhrase->nToken ){
      assert( pCsr->eEvalmode==FTS3_EVAL_FILTER && isReqPos==0 );
      fts3DoclistStripPositions(pOut, &nOut);
    }
    *paOut = pOut;
    *pnOut = nOut;
  }else{
    sqlite3_free(pOut);
  }
  return rc;
}

/*
** This function merges two doclists according to the requirements of a
** NEAR operator.
**
** Both input doclists must include position information. The output doclist 
** includes position information if the first argument to this function
** is MERGE_POS_NEAR, or does not if it is MERGE_NEAR.
*/
static int fts3NearMerge(
  int mergetype,                  /* MERGE_POS_NEAR or MERGE_NEAR */
  int nNear,                      /* Parameter to NEAR operator */
  int nTokenLeft,                 /* Number of tokens in LHS phrase arg */
  char *aLeft,                    /* Doclist for LHS (incl. positions) */
  int nLeft,                      /* Size of LHS doclist in bytes */
  int nTokenRight,                /* As nTokenLeft */
  char *aRight,                   /* As aLeft */
  int nRight,                     /* As nRight */
  char **paOut,                   /* OUT: Results of merge (malloced) */
  int *pnOut                      /* OUT: Sized of output buffer */
){
  char *aOut;                     /* Buffer to write output doclist to */
  int rc;                         /* Return code */
  char *aOut;
  int rc;

  assert( mergetype==MERGE_POS_NEAR || MERGE_NEAR );

  aOut = sqlite3_malloc(nLeft+nRight+1);
  if( aOut==0 ){
    rc = SQLITE_NOMEM;
  }else{
    rc = fts3DoclistMerge(mergetype, nNear+nTokenRight, nNear+nTokenLeft, 
      aOut, pnOut, aLeft, nLeft, aRight, nRight, 0
      aOut, pnOut, aLeft, nLeft, aRight, nRight
    );
    if( rc!=SQLITE_OK ){
      sqlite3_free(aOut);
      aOut = 0;
    }
  }

  *paOut = aOut;
  return rc;
}

/*
** This function is used as part of the processing for the snippet() and
** offsets() functions.
**
** Both pLeft and pRight are expression nodes of type FTSQUERY_PHRASE. Both
** have their respective doclists (including position information) loaded
** in Fts3Expr.aDoclist/nDoclist. This function removes all entries from
** each doclist that are not within nNear tokens of a corresponding entry
** in the other doclist.
*/
SQLITE_PRIVATE int sqlite3Fts3ExprNearTrim(Fts3Expr *pLeft, Fts3Expr *pRight, int nNear){
  int rc;                         /* Return code */
  int rc;

  assert( pLeft->eType==FTSQUERY_PHRASE );
  assert( pRight->eType==FTSQUERY_PHRASE );
  assert( pLeft->isLoaded && pRight->isLoaded );

  if( pLeft->aDoclist==0 || pRight->aDoclist==0 ){
    sqlite3_free(pLeft->aDoclist);
    sqlite3_free(pRight->aDoclist);
    pRight->aDoclist = 0;
    pLeft->aDoclist = 0;
    rc = SQLITE_OK;
  }else{
    char *aOut;                   /* Buffer in which to assemble new doclist */
    int nOut;                     /* Size of buffer aOut in bytes */
    char *aOut;
    int nOut;

    rc = fts3NearMerge(MERGE_POS_NEAR, nNear, 
        pLeft->pPhrase->nToken, pLeft->aDoclist, pLeft->nDoclist,
        pRight->pPhrase->nToken, pRight->aDoclist, pRight->nDoclist,
        &aOut, &nOut
    );
    if( rc!=SQLITE_OK ) return rc;