expr.lo fault.lo fkey.lo \
         fts3.lo fts3_aux.lo fts3_expr.lo fts3_hash.lo fts3_icu.lo \
         fts3_porter.lo fts3_snippet.lo fts3_tokenizer.lo fts3_tokenizer1.lo \
         fts3_tokenize_vtab.lo \
         fts3_unicode.lo fts3_unicode2.lo fts3_write.lo \
	 fts5.lo \
         func.lo global.lo hash.lo \
         icu.lo insert.lo journal.lo json1.lo legacy.lo loadext.lo \
         main.lo malloc.lo mem0.lo mem1.lo mem2.lo mem3.lo mem5.lo \
         memjournal.lo \
         mutex.lo mutex_noop.lo mutex_unix.lo mutex_w32.lo \
         notify.lo opcodes.lo os.lo os_unix.lo os_win.lo \
         pager.lo parse.lo pcache.lo pcache1.lo pragma.lo prepare.lo printf.lo \
         random.lo resolve.lo rowset.lo rtree.lo select.lo sqlite3rbu.lo status.lo \
         table.lo threads.lo tokenize.lo treeview.lo trigger.lo \
................................................................................
  $(TOP)/src/fkey.c \
  $(TOP)/src/func.c \
  $(TOP)/src/global.c \
  $(TOP)/src/hash.c \
  $(TOP)/src/hash.h \
  $(TOP)/src/hwtime.h \
  $(TOP)/src/insert.c \
  $(TOP)/src/journal.c \
  $(TOP)/src/legacy.c \
  $(TOP)/src/loadext.c \
  $(TOP)/src/main.c \
  $(TOP)/src/malloc.c \
  $(TOP)/src/mem0.c \
  $(TOP)/src/mem1.c \
  $(TOP)/src/mem2.c \
................................................................................

hash.lo:	$(TOP)/src/hash.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/hash.c

insert.lo:	$(TOP)/src/insert.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/insert.c

journal.lo:	$(TOP)/src/journal.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/journal.c

legacy.lo:	$(TOP)/src/legacy.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/legacy.c

loadext.lo:	$(TOP)/src/loadext.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/loadext.c

main.lo:	$(TOP)/src/main.c $(HDR)

         expr.lo fault.lo fkey.lo \
         fts3.lo fts3_aux.lo fts3_expr.lo fts3_hash.lo fts3_icu.lo \
         fts3_porter.lo fts3_snippet.lo fts3_tokenizer.lo fts3_tokenizer1.lo \
         fts3_tokenize_vtab.lo \
         fts3_unicode.lo fts3_unicode2.lo fts3_write.lo \
	 fts5.lo \
         func.lo global.lo hash.lo \
         icu.lo insert.lo json1.lo legacy.lo loadext.lo \
         main.lo malloc.lo mem0.lo mem1.lo mem2.lo mem3.lo mem5.lo \
         memjournal.lo \
         mutex.lo mutex_noop.lo mutex_unix.lo mutex_w32.lo \
         notify.lo opcodes.lo os.lo os_unix.lo os_win.lo \
         pager.lo parse.lo pcache.lo pcache1.lo pragma.lo prepare.lo printf.lo \
         random.lo resolve.lo rowset.lo rtree.lo select.lo sqlite3rbu.lo status.lo \
         table.lo threads.lo tokenize.lo treeview.lo trigger.lo \
................................................................................
  $(TOP)/src/fkey.c \
  $(TOP)/src/func.c \
  $(TOP)/src/global.c \
  $(TOP)/src/hash.c \
  $(TOP)/src/hash.h \
  $(TOP)/src/hwtime.h \
  $(TOP)/src/insert.c \

  $(TOP)/src/legacy.c \
  $(TOP)/src/loadext.c \
  $(TOP)/src/main.c \
  $(TOP)/src/malloc.c \
  $(TOP)/src/mem0.c \
  $(TOP)/src/mem1.c \
  $(TOP)/src/mem2.c \
................................................................................

hash.lo:	$(TOP)/src/hash.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/hash.c

insert.lo:	$(TOP)/src/insert.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/insert.c




legacy.lo:	$(TOP)/src/legacy.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/legacy.c

loadext.lo:	$(TOP)/src/loadext.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/loadext.c

main.lo:	$(TOP)/src/main.c $(HDR)

         callback.lo complete.lo ctime.lo date.lo dbstat.lo delete.lo \
         expr.lo fault.lo fkey.lo \
         fts3.lo fts3_aux.lo fts3_expr.lo fts3_hash.lo fts3_icu.lo \
         fts3_porter.lo fts3_snippet.lo fts3_tokenizer.lo fts3_tokenizer1.lo \
         fts3_tokenize_vtab.lo fts3_unicode.lo fts3_unicode2.lo fts3_write.lo \
         fts5.lo \
         func.lo global.lo hash.lo \
         icu.lo insert.lo journal.lo legacy.lo loadext.lo \
         main.lo malloc.lo mem0.lo mem1.lo mem2.lo mem3.lo mem5.lo \
         memjournal.lo \
         mutex.lo mutex_noop.lo mutex_unix.lo mutex_w32.lo \
         notify.lo opcodes.lo os.lo os_unix.lo os_win.lo \
         pager.lo pcache.lo pcache1.lo pragma.lo prepare.lo printf.lo \
         random.lo resolve.lo rowset.lo rtree.lo select.lo sqlite3rbu.lo status.lo \
         table.lo threads.lo tokenize.lo treeview.lo trigger.lo \
................................................................................
  $(TOP)\src\expr.c \
  $(TOP)\src\fault.c \
  $(TOP)\src\fkey.c \
  $(TOP)\src\func.c \
  $(TOP)\src\global.c \
  $(TOP)\src\hash.c \
  $(TOP)\src\insert.c \
  $(TOP)\src\journal.c \
  $(TOP)\src\legacy.c \
  $(TOP)\src\loadext.c \
  $(TOP)\src\main.c \
  $(TOP)\src\malloc.c \
  $(TOP)\src\mem0.c \
  $(TOP)\src\mem1.c \
  $(TOP)\src\mem2.c \
................................................................................

hash.lo:	$(TOP)\src\hash.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\hash.c

insert.lo:	$(TOP)\src\insert.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\insert.c

journal.lo:	$(TOP)\src\journal.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\journal.c

legacy.lo:	$(TOP)\src\legacy.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\legacy.c

loadext.lo:	$(TOP)\src\loadext.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\loadext.c

main.lo:	$(TOP)\src\main.c $(HDR)

         callback.lo complete.lo ctime.lo date.lo dbstat.lo delete.lo \
         expr.lo fault.lo fkey.lo \
         fts3.lo fts3_aux.lo fts3_expr.lo fts3_hash.lo fts3_icu.lo \
         fts3_porter.lo fts3_snippet.lo fts3_tokenizer.lo fts3_tokenizer1.lo \
         fts3_tokenize_vtab.lo fts3_unicode.lo fts3_unicode2.lo fts3_write.lo \
         fts5.lo \
         func.lo global.lo hash.lo \
         icu.lo insert.lo legacy.lo loadext.lo \
         main.lo malloc.lo mem0.lo mem1.lo mem2.lo mem3.lo mem5.lo \
         memjournal.lo \
         mutex.lo mutex_noop.lo mutex_unix.lo mutex_w32.lo \
         notify.lo opcodes.lo os.lo os_unix.lo os_win.lo \
         pager.lo pcache.lo pcache1.lo pragma.lo prepare.lo printf.lo \
         random.lo resolve.lo rowset.lo rtree.lo select.lo sqlite3rbu.lo status.lo \
         table.lo threads.lo tokenize.lo treeview.lo trigger.lo \
................................................................................
  $(TOP)\src\expr.c \
  $(TOP)\src\fault.c \
  $(TOP)\src\fkey.c \
  $(TOP)\src\func.c \
  $(TOP)\src\global.c \
  $(TOP)\src\hash.c \
  $(TOP)\src\insert.c \

  $(TOP)\src\legacy.c \
  $(TOP)\src\loadext.c \
  $(TOP)\src\main.c \
  $(TOP)\src\malloc.c \
  $(TOP)\src\mem0.c \
  $(TOP)\src\mem1.c \
  $(TOP)\src\mem2.c \
................................................................................

hash.lo:	$(TOP)\src\hash.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\hash.c

insert.lo:	$(TOP)\src\insert.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\insert.c




legacy.lo:	$(TOP)\src\legacy.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\legacy.c

loadext.lo:	$(TOP)\src\loadext.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\loadext.c

main.lo:	$(TOP)\src\main.c $(HDR)

/* 27 */ "SELECT ? UNION SELECT level / (1024 * ?) FROM %Q.'%q_segdir'",

/* This statement is used to determine which level to read the input from
** when performing an incremental merge. It returns the absolute level number
** of the oldest level in the db that contains at least ? segments. Or,
** if no level in the FTS index contains more than ? segments, the statement
** returns zero rows.  */

/* 28 */ "SELECT level FROM %Q.'%q_segdir' GROUP BY level HAVING count(*)>=?"
         "  ORDER BY (level %% 1024) ASC LIMIT 1",

/* Estimate the upper limit on the number of leaf nodes in a new segment
** created by merging the oldest :2 segments from absolute level :1. See 
** function sqlite3Fts3Incrmerge() for details.  */
/* 29 */ "SELECT 2 * total(1 + leaves_end_block - start_block) "
         "  FROM %Q.'%q_segdir' WHERE level = ? AND idx < ?",
................................................................................
    /* Search the %_segdir table for the absolute level with the smallest
    ** relative level number that contains at least nMin segments, if any.
    ** If one is found, set iAbsLevel to the absolute level number and
    ** nSeg to nMin. If no level with at least nMin segments can be found, 
    ** set nSeg to -1.
    */
    rc = fts3SqlStmt(p, SQL_FIND_MERGE_LEVEL, &pFindLevel, 0);
    sqlite3_bind_int(pFindLevel, 1, nMin);
    if( sqlite3_step(pFindLevel)==SQLITE_ROW ){
      iAbsLevel = sqlite3_column_int64(pFindLevel, 0);



      nSeg = nMin;

    }else{
      nSeg = -1;
    }
    rc = sqlite3_reset(pFindLevel);

    /* If the hint read from the %_stat table is not empty, check if the
    ** last entry in it specifies a relative level smaller than or equal
................................................................................
  /* If the first integer value is followed by a ',',  read the second
  ** integer value. */
  if( z[0]==',' && z[1]!='\0' ){
    z++;
    nMin = fts3Getint(&z);
  }

  if( z[0]!='\0' || nMin<2 ){
    rc = SQLITE_ERROR;
  }else{
    rc = SQLITE_OK;
    if( !p->bHasStat ){
      assert( p->bFts4==0 );
      sqlite3Fts3CreateStatTable(&rc, p);
    }

/* 27 */ "SELECT ? UNION SELECT level / (1024 * ?) FROM %Q.'%q_segdir'",

/* This statement is used to determine which level to read the input from
** when performing an incremental merge. It returns the absolute level number
** of the oldest level in the db that contains at least ? segments. Or,
** if no level in the FTS index contains more than ? segments, the statement
** returns zero rows.  */
/* 28 */ "SELECT level, count(*) AS cnt FROM %Q.'%q_segdir' "
         "  GROUP BY level HAVING cnt>=?"
         "  ORDER BY (level %% 1024) ASC LIMIT 1",

/* Estimate the upper limit on the number of leaf nodes in a new segment
** created by merging the oldest :2 segments from absolute level :1. See 
** function sqlite3Fts3Incrmerge() for details.  */
/* 29 */ "SELECT 2 * total(1 + leaves_end_block - start_block) "
         "  FROM %Q.'%q_segdir' WHERE level = ? AND idx < ?",
................................................................................
    /* Search the %_segdir table for the absolute level with the smallest
    ** relative level number that contains at least nMin segments, if any.
    ** If one is found, set iAbsLevel to the absolute level number and
    ** nSeg to nMin. If no level with at least nMin segments can be found, 
    ** set nSeg to -1.
    */
    rc = fts3SqlStmt(p, SQL_FIND_MERGE_LEVEL, &pFindLevel, 0);
    sqlite3_bind_int(pFindLevel, 1, MAX(2, nMin));
    if( sqlite3_step(pFindLevel)==SQLITE_ROW ){
      iAbsLevel = sqlite3_column_int64(pFindLevel, 0);
      if( nMin<2 ){
        nSeg = sqlite3_column_int(pFindLevel, 1);
      }else{
        nSeg = nMin;
      }
    }else{
      nSeg = -1;
    }
    rc = sqlite3_reset(pFindLevel);

    /* If the hint read from the %_stat table is not empty, check if the
    ** last entry in it specifies a relative level smaller than or equal
................................................................................
  /* If the first integer value is followed by a ',',  read the second
  ** integer value. */
  if( z[0]==',' && z[1]!='\0' ){
    z++;
    nMin = fts3Getint(&z);
  }

  if( z[0]!='\0' || nMin<0 || nMin==1 ){
    rc = SQLITE_ERROR;
  }else{
    rc = SQLITE_OK;
    if( !p->bHasStat ){
      assert( p->bFts4==0 );
      sqlite3Fts3CreateStatTable(&rc, p);
    }

  pIdxInfo->idxNum = 2;
  pIdxInfo->needToFreeIdxStr = 1;
  if( iIdx>0 && 0==(pIdxInfo->idxStr = sqlite3_mprintf("%s", zIdxStr)) ){
    return SQLITE_NOMEM;
  }

  nRow = pRtree->nRowEst / (iIdx + 1);
  pIdxInfo->estimatedCost = (double)6.0 * (double)nRow;
  setEstimatedRows(pIdxInfo, nRow);

  return rc;
}

/*

  pIdxInfo->idxNum = 2;
  pIdxInfo->needToFreeIdxStr = 1;
  if( iIdx>0 && 0==(pIdxInfo->idxStr = sqlite3_mprintf("%s", zIdxStr)) ){
    return SQLITE_NOMEM;
  }

  nRow = pRtree->nRowEst >> (iIdx/2);
  pIdxInfo->estimatedCost = (double)6.0 * (double)nRow;
  setEstimatedRows(pIdxInfo, nRow);

  return rc;
}

/*

         callback.o complete.o ctime.o date.o dbstat.o delete.o expr.o \
	 fault.o fkey.o \
         fts3.o fts3_aux.o fts3_expr.o fts3_hash.o fts3_icu.o fts3_porter.o \
         fts3_snippet.o fts3_tokenizer.o fts3_tokenizer1.o \
         fts3_tokenize_vtab.o \
	 fts3_unicode.o fts3_unicode2.o \
         fts3_write.o fts5.o func.o global.o hash.o \
         icu.o insert.o journal.o json1.o legacy.o loadext.o \
         main.o malloc.o mem0.o mem1.o mem2.o mem3.o mem5.o \
         memjournal.o \
         mutex.o mutex_noop.o mutex_unix.o mutex_w32.o \
         notify.o opcodes.o os.o os_unix.o os_win.o \
         pager.o pcache.o pcache1.o pragma.o prepare.o printf.o \
         random.o resolve.o rowset.o rtree.o select.o sqlite3rbu.o status.o \
         table.o threads.o tokenize.o treeview.o trigger.o \
................................................................................
  $(TOP)/src/fkey.c \
  $(TOP)/src/func.c \
  $(TOP)/src/global.c \
  $(TOP)/src/hash.c \
  $(TOP)/src/hash.h \
  $(TOP)/src/hwtime.h \
  $(TOP)/src/insert.c \
  $(TOP)/src/journal.c \
  $(TOP)/src/legacy.c \
  $(TOP)/src/loadext.c \
  $(TOP)/src/main.c \
  $(TOP)/src/malloc.c \
  $(TOP)/src/mem0.c \
  $(TOP)/src/mem1.c \
  $(TOP)/src/mem2.c \

         callback.o complete.o ctime.o date.o dbstat.o delete.o expr.o \
	 fault.o fkey.o \
         fts3.o fts3_aux.o fts3_expr.o fts3_hash.o fts3_icu.o fts3_porter.o \
         fts3_snippet.o fts3_tokenizer.o fts3_tokenizer1.o \
         fts3_tokenize_vtab.o \
	 fts3_unicode.o fts3_unicode2.o \
         fts3_write.o fts5.o func.o global.o hash.o \
         icu.o insert.o json1.o legacy.o loadext.o \
         main.o malloc.o mem0.o mem1.o mem2.o mem3.o mem5.o \
         memjournal.o \
         mutex.o mutex_noop.o mutex_unix.o mutex_w32.o \
         notify.o opcodes.o os.o os_unix.o os_win.o \
         pager.o pcache.o pcache1.o pragma.o prepare.o printf.o \
         random.o resolve.o rowset.o rtree.o select.o sqlite3rbu.o status.o \
         table.o threads.o tokenize.o treeview.o trigger.o \
................................................................................
  $(TOP)/src/fkey.c \
  $(TOP)/src/func.c \
  $(TOP)/src/global.c \
  $(TOP)/src/hash.c \
  $(TOP)/src/hash.h \
  $(TOP)/src/hwtime.h \
  $(TOP)/src/insert.c \

  $(TOP)/src/legacy.c \
  $(TOP)/src/loadext.c \
  $(TOP)/src/main.c \
  $(TOP)/src/malloc.c \
  $(TOP)/src/mem0.c \
  $(TOP)/src/mem1.c \
  $(TOP)/src/mem2.c \

/* The minimum PMA size is set to this value multiplied by the database
** page size in bytes.
*/
#ifndef SQLITE_SORTER_PMASZ
# define SQLITE_SORTER_PMASZ 250
#endif













/*
** The following singleton contains the global configuration for
** the SQLite library.
*/
SQLITE_WSD struct Sqlite3Config sqlite3Config = {
   SQLITE_DEFAULT_MEMSTATUS,  /* bMemstat */
   1,                         /* bCoreMutex */
................................................................................
   SQLITE_THREADSAFE==1,      /* bFullMutex */
   SQLITE_USE_URI,            /* bOpenUri */
   SQLITE_ALLOW_COVERING_INDEX_SCAN,   /* bUseCis */
   0x7ffffffe,                /* mxStrlen */
   0,                         /* neverCorrupt */
   128,                       /* szLookaside */
   500,                       /* nLookaside */

   {0,0,0,0,0,0,0,0},         /* m */
   {0,0,0,0,0,0,0,0,0},       /* mutex */
   {0,0,0,0,0,0,0,0,0,0,0,0,0},/* pcache2 */
   (void*)0,                  /* pHeap */
   0,                         /* nHeap */
   0, 0,                      /* mnHeap, mxHeap */
   SQLITE_DEFAULT_MMAP_SIZE,  /* szMmap */

/* The minimum PMA size is set to this value multiplied by the database
** page size in bytes.
*/
#ifndef SQLITE_SORTER_PMASZ
# define SQLITE_SORTER_PMASZ 250
#endif

/* Statement journals spill to disk when their size exceeds the following
** threashold (in bytes). 0 means that statement journals are created and
** written to disk immediately (the default behavior for SQLite versions
** before 3.12.0).  -1 means always keep the entire statement journal in
** memory.  (The statement journal is also always held entirely in memory
** if journal_mode=MEMORY or if temp_store=MEMORY, regardless of this
** setting.)
*/
#ifndef SQLITE_STMTJRNL_SPILL 
# define SQLITE_STMTJRNL_SPILL (64*1024)
#endif

/*
** The following singleton contains the global configuration for
** the SQLite library.
*/
SQLITE_WSD struct Sqlite3Config sqlite3Config = {
   SQLITE_DEFAULT_MEMSTATUS,  /* bMemstat */
   1,                         /* bCoreMutex */
................................................................................
   SQLITE_THREADSAFE==1,      /* bFullMutex */
   SQLITE_USE_URI,            /* bOpenUri */
   SQLITE_ALLOW_COVERING_INDEX_SCAN,   /* bUseCis */
   0x7ffffffe,                /* mxStrlen */
   0,                         /* neverCorrupt */
   128,                       /* szLookaside */
   500,                       /* nLookaside */
   SQLITE_STMTJRNL_SPILL,     /* nStmtSpill */
   {0,0,0,0,0,0,0,0},         /* m */
   {0,0,0,0,0,0,0,0,0},       /* mutex */
   {0,0,0,0,0,0,0,0,0,0,0,0,0},/* pcache2 */
   (void*)0,                  /* pHeap */
   0,                         /* nHeap */
   0, 0,                      /* mnHeap, mxHeap */
   SQLITE_DEFAULT_MMAP_SIZE,  /* szMmap */

/*
** 2007 August 22
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This file implements a special kind of sqlite3_file object used
** by SQLite to create journal files if the atomic-write optimization
** is enabled.
**
** The distinctive characteristic of this sqlite3_file is that the
** actual on disk file is created lazily. When the file is created,
** the caller specifies a buffer size for an in-memory buffer to
** be used to service read() and write() requests. The actual file
** on disk is not created or populated until either:
**
**   1) The in-memory representation grows too large for the allocated 
**      buffer, or
**   2) The sqlite3JournalCreate() function is called.
*/
#if 0 
#ifdef SQLITE_ENABLE_ATOMIC_WRITE
#include "sqliteInt.h"


/*
** A JournalFile object is a subclass of sqlite3_file used by
** as an open file handle for journal files.
*/
struct JournalFile {
  sqlite3_io_methods *pMethod;    /* I/O methods on journal files */
  int nBuf;                       /* Size of zBuf[] in bytes */
  char *zBuf;                     /* Space to buffer journal writes */
  int iSize;                      /* Amount of zBuf[] currently used */
  int flags;                      /* xOpen flags */
  sqlite3_vfs *pVfs;              /* The "real" underlying VFS */
  sqlite3_file *pReal;            /* The "real" underlying file descriptor */
  const char *zJournal;           /* Name of the journal file */
};
typedef struct JournalFile JournalFile;

/*
** If it does not already exists, create and populate the on-disk file 
** for JournalFile p.
*/
static int createFile(JournalFile *p){
  int rc = SQLITE_OK;
  if( !p->pReal ){
    sqlite3_file *pReal = (sqlite3_file *)&p[1];
    rc = sqlite3OsOpen(p->pVfs, p->zJournal, pReal, p->flags, 0);
    if( rc==SQLITE_OK ){
      p->pReal = pReal;
      if( p->iSize>0 ){
        assert(p->iSize<=p->nBuf);
        rc = sqlite3OsWrite(p->pReal, p->zBuf, p->iSize, 0);
      }
      if( rc!=SQLITE_OK ){
        /* If an error occurred while writing to the file, close it before
        ** returning. This way, SQLite uses the in-memory journal data to 
        ** roll back changes made to the internal page-cache before this
        ** function was called.  */
        sqlite3OsClose(pReal);
        p->pReal = 0;
      }
    }
  }
  return rc;
}

/*
** Close the file.
*/
static int jrnlClose(sqlite3_file *pJfd){
  JournalFile *p = (JournalFile *)pJfd;
  if( p->pReal ){
    sqlite3OsClose(p->pReal);
  }
  sqlite3_free(p->zBuf);
  return SQLITE_OK;
}

/*
** Read data from the file.
*/
static int jrnlRead(
  sqlite3_file *pJfd,    /* The journal file from which to read */
  void *zBuf,            /* Put the results here */
  int iAmt,              /* Number of bytes to read */
  sqlite_int64 iOfst     /* Begin reading at this offset */
){
  int rc = SQLITE_OK;
  JournalFile *p = (JournalFile *)pJfd;
  if( p->pReal ){
    rc = sqlite3OsRead(p->pReal, zBuf, iAmt, iOfst);
  }else if( (iAmt+iOfst)>p->iSize ){
    rc = SQLITE_IOERR_SHORT_READ;
  }else{
    memcpy(zBuf, &p->zBuf[iOfst], iAmt);
  }
  return rc;
}

/*
** Write data to the file.
*/
static int jrnlWrite(
  sqlite3_file *pJfd,    /* The journal file into which to write */
  const void *zBuf,      /* Take data to be written from here */
  int iAmt,              /* Number of bytes to write */
  sqlite_int64 iOfst     /* Begin writing at this offset into the file */
){
  int rc = SQLITE_OK;
  JournalFile *p = (JournalFile *)pJfd;
  if( !p->pReal && (iOfst+iAmt)>p->nBuf ){
    rc = createFile(p);
  }
  if( rc==SQLITE_OK ){
    if( p->pReal ){
      rc = sqlite3OsWrite(p->pReal, zBuf, iAmt, iOfst);
    }else{
      memcpy(&p->zBuf[iOfst], zBuf, iAmt);
      if( p->iSize<(iOfst+iAmt) ){
        p->iSize = (iOfst+iAmt);
      }
    }
  }
  return rc;
}

/*
** Truncate the file.
*/
static int jrnlTruncate(sqlite3_file *pJfd, sqlite_int64 size){
  int rc = SQLITE_OK;
  JournalFile *p = (JournalFile *)pJfd;
  if( p->pReal ){
    rc = sqlite3OsTruncate(p->pReal, size);
  }else if( size<p->iSize ){
    p->iSize = size;
  }
  return rc;
}

/*
** Sync the file.
*/
static int jrnlSync(sqlite3_file *pJfd, int flags){
  int rc;
  JournalFile *p = (JournalFile *)pJfd;
  if( p->pReal ){
    rc = sqlite3OsSync(p->pReal, flags);
  }else{
    rc = SQLITE_OK;
  }
  return rc;
}

/*
** Query the size of the file in bytes.
*/
static int jrnlFileSize(sqlite3_file *pJfd, sqlite_int64 *pSize){
  int rc = SQLITE_OK;
  JournalFile *p = (JournalFile *)pJfd;
  if( p->pReal ){
    rc = sqlite3OsFileSize(p->pReal, pSize);
  }else{
    *pSize = (sqlite_int64) p->iSize;
  }
  return rc;
}

/*
** Table of methods for JournalFile sqlite3_file object.
*/
static struct sqlite3_io_methods JournalFileMethods = {
  1,             /* iVersion */
  jrnlClose,     /* xClose */
  jrnlRead,      /* xRead */
  jrnlWrite,     /* xWrite */
  jrnlTruncate,  /* xTruncate */
  jrnlSync,      /* xSync */
  jrnlFileSize,  /* xFileSize */
  0,             /* xLock */
  0,             /* xUnlock */
  0,             /* xCheckReservedLock */
  0,             /* xFileControl */
  0,             /* xSectorSize */
  0,             /* xDeviceCharacteristics */
  0,             /* xShmMap */
  0,             /* xShmLock */
  0,             /* xShmBarrier */
  0              /* xShmUnmap */
};

/* 
** Open a journal file.
*/
int sqlite3JournalOpen(
  sqlite3_vfs *pVfs,         /* The VFS to use for actual file I/O */
  const char *zName,         /* Name of the journal file */
  sqlite3_file *pJfd,        /* Preallocated, blank file handle */
  int flags,                 /* Opening flags */
  int nBuf                   /* Bytes buffered before opening the file */
){
  JournalFile *p = (JournalFile *)pJfd;
  memset(p, 0, sqlite3JournalSize(pVfs));
  if( nBuf>0 ){
    p->zBuf = sqlite3MallocZero(nBuf);
    if( !p->zBuf ){
      return SQLITE_NOMEM_BKPT;
    }
  }else{
    return sqlite3OsOpen(pVfs, zName, pJfd, flags, 0);
  }
  p->pMethod = &JournalFileMethods;
  p->nBuf = nBuf;
  p->flags = flags;
  p->zJournal = zName;
  p->pVfs = pVfs;
  return SQLITE_OK;
}

/*
** If the argument p points to a JournalFile structure, and the underlying
** file has not yet been created, create it now.
*/
int sqlite3JournalCreate(sqlite3_file *p){
  if( p->pMethods!=&JournalFileMethods ){
    return SQLITE_OK;
  }
  return createFile((JournalFile *)p);
}

/*
** The file-handle passed as the only argument is guaranteed to be an open
** file. It may or may not be of class JournalFile. If the file is a
** JournalFile, and the underlying file on disk has not yet been opened,
** return 0. Otherwise, return 1.
*/
int sqlite3JournalExists(sqlite3_file *p){
  return (p->pMethods!=&JournalFileMethods || ((JournalFile *)p)->pReal!=0);
}

/* 
** Return the number of bytes required to store a JournalFile that uses vfs
** pVfs to create the underlying on-disk files.
*/
int sqlite3JournalSize(sqlite3_vfs *pVfs){
  return (pVfs->szOsFile+sizeof(JournalFile));
}
#endif
#endif

    }
#endif

    case SQLITE_CONFIG_PMASZ: {
      sqlite3GlobalConfig.szPma = va_arg(ap, unsigned int);
      break;
    }






    default: {
      rc = SQLITE_ERROR;
      break;
    }
  }
  va_end(ap);

    }
#endif

    case SQLITE_CONFIG_PMASZ: {
      sqlite3GlobalConfig.szPma = va_arg(ap, unsigned int);
      break;
    }

    case SQLITE_CONFIG_STMTJRNL_SPILL: {
      sqlite3GlobalConfig.nStmtSpill = va_arg(ap, int);
      break;
    }

    default: {
      rc = SQLITE_ERROR;
      break;
    }
  }
  va_end(ap);

** This structure is a subclass of sqlite3_file. Each open memory-journal
** is an instance of this class.
*/
struct MemJournal {
  const sqlite3_io_methods *pMethod; /* Parent class. MUST BE FIRST */
  int nChunkSize;                 /* In-memory chunk-size */

  int nBuf;                       /* Bytes of data before flushing */
  int nSize;                      /* Bytes of data currently in memory */
  FileChunk *pFirst;              /* Head of in-memory chunk-list */
  FilePoint endpoint;             /* Pointer to the end of the file */
  FilePoint readpoint;            /* Pointer to the end of the last xRead() */

  int flags;                      /* xOpen flags */
  sqlite3_vfs *pVfs;              /* The "real" underlying VFS */
................................................................................
      pChunk = p->readpoint.pChunk;
    }

    iChunkOffset = (int)(iOfst%p->nChunkSize);
    do {
      int iSpace = p->nChunkSize - iChunkOffset;
      int nCopy = MIN(nRead, (p->nChunkSize - iChunkOffset));
      memcpy(zOut, &pChunk->zChunk[iChunkOffset], nCopy);
      zOut += nCopy;
      nRead -= iSpace;
      iChunkOffset = 0;
    } while( nRead>=0 && (pChunk=pChunk->pNext)!=0 && nRead>0 );
    p->readpoint.iOffset = iOfst+iAmt;
    p->readpoint.pChunk = pChunk;
  }
................................................................................
  } 
  p->pFirst = 0;
}

/*
** Flush the contents of memory to a real file on disk.
*/
static int createFile(MemJournal *p){
  int rc = SQLITE_OK;
  if( !p->pReal ){
    sqlite3_file *pReal = (sqlite3_file *)&p[1];
    rc = sqlite3OsOpen(p->pVfs, p->zJournal, pReal, p->flags, 0);
    if( rc==SQLITE_OK ){
      int nChunk = p->nChunkSize;
      i64 iOff = 0;
................................................................................
      p->pReal = pReal;
      for(pIter=p->pFirst; pIter && rc==SQLITE_OK; pIter=pIter->pNext){
        int nWrite = nChunk;
        if( pIter==p->endpoint.pChunk ){
          nWrite = p->endpoint.iOffset % p->nChunkSize;
          if( nWrite==0 ) nWrite = p->nChunkSize;
        }
        rc = sqlite3OsWrite(pReal, pIter->zChunk, nWrite, iOff);
        iOff += nWrite;
      }
      if( rc!=SQLITE_OK ){
        /* If an error occurred while writing to the file, close it before
        ** returning. This way, SQLite uses the in-memory journal data to 
        ** roll back changes made to the internal page-cache before this
        ** function was called.  */
................................................................................

  /* If the file has already been created on disk. */
  if( p->pReal ){
    return sqlite3OsWrite(p->pReal, zBuf, iAmt, iOfst);
  }

  /* If the file should be created now. */
  else if( p->nBuf>0 && (iAmt+iOfst)>p->nBuf ){
    int rc = createFile(p);
    if( rc==SQLITE_OK ){
      rc = memjrnlWrite(pJfd, zBuf, iAmt, iOfst);
    }
    return rc;
  }

  /* If the contents of this write should be stored in memory */
................................................................................
    ** access writes are not required. The only exception to this is when
    ** the in-memory journal is being used by a connection using the
    ** atomic-write optimization. In this case the first 28 bytes of the
    ** journal file may be written as part of committing the transaction. */ 
    assert( iOfst==p->endpoint.iOffset || iOfst==0 );
    if( iOfst==0 && p->pFirst ){
      assert( p->nChunkSize>iAmt );
      memcpy(p->pFirst->zChunk, zBuf, iAmt);
    }else{
      while( nWrite>0 ){
        FileChunk *pChunk = p->endpoint.pChunk;
        int iChunkOffset = (int)(p->endpoint.iOffset%p->nChunkSize);
        int iSpace = MIN(nWrite, p->nChunkSize - iChunkOffset);

        if( iChunkOffset==0 ){
................................................................................
          }else{
            assert( !p->pFirst );
            p->pFirst = pNew;
          }
          p->endpoint.pChunk = pNew;
        }

        memcpy(&p->endpoint.pChunk->zChunk[iChunkOffset], zWrite, iSpace);
        zWrite += iSpace;
        nWrite -= iSpace;
        p->endpoint.iOffset += iSpace;
      }
      p->nSize = iAmt + iOfst;
    }
  }
................................................................................
  0                 /* xUnfetch */
};

/* 
** Open a journal file. 
**
** The behaviour of the journal file depends on the value of parameter 
** nBuf. If nBuf is 0, then the journal file is always create and 
** accessed using the underlying VFS. If nBuf is less than zero, then
** all content is always stored in main-memory. Finally, if nBuf is a
** positive value, then the journal file is initially created in-memory
** but may be flushed to disk later on. In this case the journal file is
** flushed to disk either when it grows larger than nBuf bytes in size,
** or when sqlite3JournalCreate() is called.
*/
int sqlite3JournalOpen(
  sqlite3_vfs *pVfs,         /* The VFS to use for actual file I/O */
  const char *zName,         /* Name of the journal file */
  sqlite3_file *pJfd,        /* Preallocated, blank file handle */
  int flags,                 /* Opening flags */
  int nBuf                   /* Bytes buffered before opening the file */
){
  MemJournal *p = (MemJournal*)pJfd;

  /* Zero the file-handle object. If nBuf was passed zero, initialize
  ** it using the sqlite3OsOpen() function of the underlying VFS. In this
  ** case none of the code in this module is executed as a result of calls
  ** made on the journal file-handle.  */
  memset(p, 0, sizeof(MemJournal) + (pVfs ? pVfs->szOsFile : 0));
  if( nBuf==0 ){
    return sqlite3OsOpen(pVfs, zName, pJfd, flags, 0);
  }

  if( nBuf>0 ){
    p->nChunkSize = nBuf;
  }else{
    p->nChunkSize = 8 + MEMJOURNAL_DFLT_FILECHUNKSIZE - sizeof(FileChunk);
    assert( MEMJOURNAL_DFLT_FILECHUNKSIZE==fileChunkSize(p->nChunkSize) );
  }

  p->pMethod = (const sqlite3_io_methods*)&MemJournalMethods;
  p->nBuf = nBuf;
  p->flags = flags;
  p->zJournal = zName;
  p->pVfs = pVfs;
  return SQLITE_OK;
}

/*
................................................................................
  sqlite3JournalOpen(0, 0, pJfd, 0, -1);
}

#ifdef SQLITE_ENABLE_ATOMIC_WRITE
/*
** If the argument p points to a MemJournal structure that is not an 
** in-memory-only journal file (i.e. is one that was opened with a +ve
** nBuf parameter), and the underlying file has not yet been created, 
** create it now.
*/
int sqlite3JournalCreate(sqlite3_file *p){
  int rc = SQLITE_OK;
  if( p->pMethods==&MemJournalMethods && ((MemJournal*)p)->nBuf>0 ){
    rc = createFile((MemJournal*)p);
  }
  return rc;
}
#endif

/*
** The file-handle passed as the only argument is open on a journal file.

** This structure is a subclass of sqlite3_file. Each open memory-journal
** is an instance of this class.
*/
struct MemJournal {
  const sqlite3_io_methods *pMethod; /* Parent class. MUST BE FIRST */
  int nChunkSize;                 /* In-memory chunk-size */

  int nSpill;                     /* Bytes of data before flushing */
  int nSize;                      /* Bytes of data currently in memory */
  FileChunk *pFirst;              /* Head of in-memory chunk-list */
  FilePoint endpoint;             /* Pointer to the end of the file */
  FilePoint readpoint;            /* Pointer to the end of the last xRead() */

  int flags;                      /* xOpen flags */
  sqlite3_vfs *pVfs;              /* The "real" underlying VFS */
................................................................................
      pChunk = p->readpoint.pChunk;
    }

    iChunkOffset = (int)(iOfst%p->nChunkSize);
    do {
      int iSpace = p->nChunkSize - iChunkOffset;
      int nCopy = MIN(nRead, (p->nChunkSize - iChunkOffset));
      memcpy(zOut, (u8*)pChunk->zChunk + iChunkOffset, nCopy);
      zOut += nCopy;
      nRead -= iSpace;
      iChunkOffset = 0;
    } while( nRead>=0 && (pChunk=pChunk->pNext)!=0 && nRead>0 );
    p->readpoint.iOffset = iOfst+iAmt;
    p->readpoint.pChunk = pChunk;
  }
................................................................................
  } 
  p->pFirst = 0;
}

/*
** Flush the contents of memory to a real file on disk.
*/
static int memjrnlCreateFile(MemJournal *p){
  int rc = SQLITE_OK;
  if( !p->pReal ){
    sqlite3_file *pReal = (sqlite3_file *)&p[1];
    rc = sqlite3OsOpen(p->pVfs, p->zJournal, pReal, p->flags, 0);
    if( rc==SQLITE_OK ){
      int nChunk = p->nChunkSize;
      i64 iOff = 0;
................................................................................
      p->pReal = pReal;
      for(pIter=p->pFirst; pIter && rc==SQLITE_OK; pIter=pIter->pNext){
        int nWrite = nChunk;
        if( pIter==p->endpoint.pChunk ){
          nWrite = p->endpoint.iOffset % p->nChunkSize;
          if( nWrite==0 ) nWrite = p->nChunkSize;
        }
        rc = sqlite3OsWrite(pReal, (u8*)pIter->zChunk, nWrite, iOff);
        iOff += nWrite;
      }
      if( rc!=SQLITE_OK ){
        /* If an error occurred while writing to the file, close it before
        ** returning. This way, SQLite uses the in-memory journal data to 
        ** roll back changes made to the internal page-cache before this
        ** function was called.  */
................................................................................

  /* If the file has already been created on disk. */
  if( p->pReal ){
    return sqlite3OsWrite(p->pReal, zBuf, iAmt, iOfst);
  }

  /* If the file should be created now. */
  else if( p->nSpill>0 && (iAmt+iOfst)>p->nSpill ){
    int rc = memjrnlCreateFile(p);
    if( rc==SQLITE_OK ){
      rc = memjrnlWrite(pJfd, zBuf, iAmt, iOfst);
    }
    return rc;
  }

  /* If the contents of this write should be stored in memory */
................................................................................
    ** access writes are not required. The only exception to this is when
    ** the in-memory journal is being used by a connection using the
    ** atomic-write optimization. In this case the first 28 bytes of the
    ** journal file may be written as part of committing the transaction. */ 
    assert( iOfst==p->endpoint.iOffset || iOfst==0 );
    if( iOfst==0 && p->pFirst ){
      assert( p->nChunkSize>iAmt );
      memcpy((u8*)p->pFirst->zChunk, zBuf, iAmt);
    }else{
      while( nWrite>0 ){
        FileChunk *pChunk = p->endpoint.pChunk;
        int iChunkOffset = (int)(p->endpoint.iOffset%p->nChunkSize);
        int iSpace = MIN(nWrite, p->nChunkSize - iChunkOffset);

        if( iChunkOffset==0 ){
................................................................................
          }else{
            assert( !p->pFirst );
            p->pFirst = pNew;
          }
          p->endpoint.pChunk = pNew;
        }

        memcpy((u8*)p->endpoint.pChunk->zChunk + iChunkOffset, zWrite, iSpace);
        zWrite += iSpace;
        nWrite -= iSpace;
        p->endpoint.iOffset += iSpace;
      }
      p->nSize = iAmt + iOfst;
    }
  }
................................................................................
  0                 /* xUnfetch */
};

/* 
** Open a journal file. 
**
** The behaviour of the journal file depends on the value of parameter 
** nSpill. If nSpill is 0, then the journal file is always create and 
** accessed using the underlying VFS. If nSpill is less than zero, then
** all content is always stored in main-memory. Finally, if nSpill is a
** positive value, then the journal file is initially created in-memory
** but may be flushed to disk later on. In this case the journal file is
** flushed to disk either when it grows larger than nSpill bytes in size,
** or when sqlite3JournalCreate() is called.
*/
int sqlite3JournalOpen(
  sqlite3_vfs *pVfs,         /* The VFS to use for actual file I/O */
  const char *zName,         /* Name of the journal file */
  sqlite3_file *pJfd,        /* Preallocated, blank file handle */
  int flags,                 /* Opening flags */
  int nSpill                 /* Bytes buffered before opening the file */
){
  MemJournal *p = (MemJournal*)pJfd;

  /* Zero the file-handle object. If nSpill was passed zero, initialize
  ** it using the sqlite3OsOpen() function of the underlying VFS. In this
  ** case none of the code in this module is executed as a result of calls
  ** made on the journal file-handle.  */
  memset(p, 0, sizeof(MemJournal) + (pVfs ? pVfs->szOsFile : 0));
  if( nSpill==0 ){
    return sqlite3OsOpen(pVfs, zName, pJfd, flags, 0);
  }

  if( nSpill>0 ){
    p->nChunkSize = nSpill;
  }else{
    p->nChunkSize = 8 + MEMJOURNAL_DFLT_FILECHUNKSIZE - sizeof(FileChunk);
    assert( MEMJOURNAL_DFLT_FILECHUNKSIZE==fileChunkSize(p->nChunkSize) );
  }

  p->pMethod = (const sqlite3_io_methods*)&MemJournalMethods;
  p->nSpill = nSpill;
  p->flags = flags;
  p->zJournal = zName;
  p->pVfs = pVfs;
  return SQLITE_OK;
}

/*
................................................................................
  sqlite3JournalOpen(0, 0, pJfd, 0, -1);
}

#ifdef SQLITE_ENABLE_ATOMIC_WRITE
/*
** If the argument p points to a MemJournal structure that is not an 
** in-memory-only journal file (i.e. is one that was opened with a +ve
** nSpill parameter), and the underlying file has not yet been created, 
** create it now.
*/
int sqlite3JournalCreate(sqlite3_file *p){
  int rc = SQLITE_OK;
  if( p->pMethods==&MemJournalMethods && ((MemJournal*)p)->nSpill>0 ){
    rc = memjrnlCreateFile((MemJournal*)p);
  }
  return rc;
}
#endif

/*
** The file-handle passed as the only argument is open on a journal file.

*/
static int openSubJournal(Pager *pPager){
  int rc = SQLITE_OK;
  if( !isOpen(pPager->sjfd) ){
    const int flags =  SQLITE_OPEN_SUBJOURNAL | SQLITE_OPEN_READWRITE 
      | SQLITE_OPEN_CREATE | SQLITE_OPEN_EXCLUSIVE 
      | SQLITE_OPEN_DELETEONCLOSE;
    int nBuf = 64*1024;
    if( pPager->journalMode==PAGER_JOURNALMODE_MEMORY || pPager->subjInMemory ){
      nBuf = -1;
    }
    rc = sqlite3JournalOpen(pPager->pVfs, 0, pPager->sjfd, flags, nBuf);
  }
  return rc;
}

/*
** Append a record of the current state of page pPg to the sub-journal. 
**

*/
static int openSubJournal(Pager *pPager){
  int rc = SQLITE_OK;
  if( !isOpen(pPager->sjfd) ){
    const int flags =  SQLITE_OPEN_SUBJOURNAL | SQLITE_OPEN_READWRITE 
      | SQLITE_OPEN_CREATE | SQLITE_OPEN_EXCLUSIVE 
      | SQLITE_OPEN_DELETEONCLOSE;
    int nStmtSpill = sqlite3Config.nStmtSpill;
    if( pPager->journalMode==PAGER_JOURNALMODE_MEMORY || pPager->subjInMemory ){
      nStmtSpill = -1;
    }
    rc = sqlite3JournalOpen(pPager->pVfs, 0, pPager->sjfd, flags, nStmtSpill);
  }
  return rc;
}

/*
** Append a record of the current state of page pPg to the sub-journal. 
**

** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded
** sorter to that integer.  The default minimum PMA Size is set by the
** [SQLITE_SORTER_PMASZ] compile-time option.  New threads are launched
** to help with sort operations when multithreaded sorting
** is enabled (using the [PRAGMA threads] command) and the amount of content
** to be sorted exceeds the page size times the minimum of the
** [PRAGMA cache_size] setting and this value.














** </dl>
*/
#define SQLITE_CONFIG_SINGLETHREAD  1  /* nil */
#define SQLITE_CONFIG_MULTITHREAD   2  /* nil */
#define SQLITE_CONFIG_SERIALIZED    3  /* nil */
#define SQLITE_CONFIG_MALLOC        4  /* sqlite3_mem_methods* */
#define SQLITE_CONFIG_GETMALLOC     5  /* sqlite3_mem_methods* */
................................................................................
#define SQLITE_CONFIG_GETPCACHE2   19  /* sqlite3_pcache_methods2* */
#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20  /* int */
#define SQLITE_CONFIG_SQLLOG       21  /* xSqllog, void* */
#define SQLITE_CONFIG_MMAP_SIZE    22  /* sqlite3_int64, sqlite3_int64 */
#define SQLITE_CONFIG_WIN32_HEAPSIZE      23  /* int nByte */
#define SQLITE_CONFIG_PCACHE_HDRSZ        24  /* int *psz */
#define SQLITE_CONFIG_PMASZ               25  /* unsigned int szPma */


/*
** CAPI3REF: Database Connection Configuration Options
**
** These constants are the available integer configuration options that
** can be passed as the second argument to the [sqlite3_db_config()] interface.
**

** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded
** sorter to that integer.  The default minimum PMA Size is set by the
** [SQLITE_SORTER_PMASZ] compile-time option.  New threads are launched
** to help with sort operations when multithreaded sorting
** is enabled (using the [PRAGMA threads] command) and the amount of content
** to be sorted exceeds the page size times the minimum of the
** [PRAGMA cache_size] setting and this value.
**
** [[SQLITE_CONFIG_STMTJRNL_SPILL]]
** <dt>SQLITE_CONFIG_STMTJRNL_SPILL
** <dd>^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which
** becomes the [statement journal] spill-to-disk threshold.  
** [Statement journals] are held in memory until their size (in bytes)
** exceeds this threshold, at which point they are written to disk.
** Or if the threshold is -1, statement journals are always held
** exclusively in memory.
** Since many statement journals never become large, setting the spill
** threshold to a value such as 64KiB can greatly reduce the amount of
** I/O required to support statement rollback.
** The default value for this setting is controlled by the
** [SQLITE_STMTJRNL_SPILL] compile-time option.
** </dl>
*/
#define SQLITE_CONFIG_SINGLETHREAD  1  /* nil */
#define SQLITE_CONFIG_MULTITHREAD   2  /* nil */
#define SQLITE_CONFIG_SERIALIZED    3  /* nil */
#define SQLITE_CONFIG_MALLOC        4  /* sqlite3_mem_methods* */
#define SQLITE_CONFIG_GETMALLOC     5  /* sqlite3_mem_methods* */
................................................................................
#define SQLITE_CONFIG_GETPCACHE2   19  /* sqlite3_pcache_methods2* */
#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20  /* int */
#define SQLITE_CONFIG_SQLLOG       21  /* xSqllog, void* */
#define SQLITE_CONFIG_MMAP_SIZE    22  /* sqlite3_int64, sqlite3_int64 */
#define SQLITE_CONFIG_WIN32_HEAPSIZE      23  /* int nByte */
#define SQLITE_CONFIG_PCACHE_HDRSZ        24  /* int *psz */
#define SQLITE_CONFIG_PMASZ               25  /* unsigned int szPma */
#define SQLITE_CONFIG_STMTJRNL_SPILL      26  /* int nByte */

/*
** CAPI3REF: Database Connection Configuration Options
**
** These constants are the available integer configuration options that
** can be passed as the second argument to the [sqlite3_db_config()] interface.
**

  int bFullMutex;                   /* True to enable full mutexing */
  int bOpenUri;                     /* True to interpret filenames as URIs */
  int bUseCis;                      /* Use covering indices for full-scans */
  int mxStrlen;                     /* Maximum string length */
  int neverCorrupt;                 /* Database is always well-formed */
  int szLookaside;                  /* Default lookaside buffer size */
  int nLookaside;                   /* Default lookaside buffer count */

  sqlite3_mem_methods m;            /* Low-level memory allocation interface */
  sqlite3_mutex_methods mutex;      /* Low-level mutex interface */
  sqlite3_pcache_methods2 pcache2;  /* Low-level page-cache interface */
  void *pHeap;                      /* Heap storage space */
  int nHeap;                        /* Size of pHeap[] */
  int mnReq, mxReq;                 /* Min and max heap requests sizes */
  sqlite3_int64 szMmap;             /* mmap() space per open file */
................................................................................
int sqlite3Utf8CharLen(const char *pData, int nByte);
u32 sqlite3Utf8Read(const u8**);
LogEst sqlite3LogEst(u64);
LogEst sqlite3LogEstAdd(LogEst,LogEst);
#ifndef SQLITE_OMIT_VIRTUALTABLE
LogEst sqlite3LogEstFromDouble(double);
#endif
#if defined(SQLITE_ENABLE_STMT_SCANSTAT) || \
    defined(SQLITE_ENABLE_STAT3_OR_STAT4) || \
    defined(SQLITE_EXPLAIN_ESTIMATED_ROWS)
u64 sqlite3LogEstToInt(LogEst);
#endif

/*
** Routines to read and write variable-length integers.  These used to

  int bFullMutex;                   /* True to enable full mutexing */
  int bOpenUri;                     /* True to interpret filenames as URIs */
  int bUseCis;                      /* Use covering indices for full-scans */
  int mxStrlen;                     /* Maximum string length */
  int neverCorrupt;                 /* Database is always well-formed */
  int szLookaside;                  /* Default lookaside buffer size */
  int nLookaside;                   /* Default lookaside buffer count */
  int nStmtSpill;                   /* Stmt-journal spill-to-disk threshold */
  sqlite3_mem_methods m;            /* Low-level memory allocation interface */
  sqlite3_mutex_methods mutex;      /* Low-level mutex interface */
  sqlite3_pcache_methods2 pcache2;  /* Low-level page-cache interface */
  void *pHeap;                      /* Heap storage space */
  int nHeap;                        /* Size of pHeap[] */
  int mnReq, mxReq;                 /* Min and max heap requests sizes */
  sqlite3_int64 szMmap;             /* mmap() space per open file */
................................................................................
int sqlite3Utf8CharLen(const char *pData, int nByte);
u32 sqlite3Utf8Read(const u8**);
LogEst sqlite3LogEst(u64);
LogEst sqlite3LogEstAdd(LogEst,LogEst);
#ifndef SQLITE_OMIT_VIRTUALTABLE
LogEst sqlite3LogEstFromDouble(double);
#endif
#if defined(SQLITE_ENABLE_STMT_SCANSTATUS) || \
    defined(SQLITE_ENABLE_STAT3_OR_STAT4) || \
    defined(SQLITE_EXPLAIN_ESTIMATED_ROWS)
u64 sqlite3LogEstToInt(LogEst);
#endif

/*
** Routines to read and write variable-length integers.  These used to

};

/* A tcl cursor object */
struct tcl_cursor {
  sqlite3_vtab_cursor base;
  sqlite3_stmt *pStmt;            /* Read data from here */
};



































/*
** This function is the implementation of both the xConnect and xCreate
** methods of the fs virtual table.
**
** The argv[] array contains the following:
**
................................................................................
  sqlite3 *db,
  void *pAux,
  int argc, const char *const*argv,
  sqlite3_vtab **ppVtab,
  char **pzErr
){
  Tcl_Interp *interp = (Tcl_Interp*)pAux;
  tcl_vtab *pTab;
  const char *zCmd;
  Tcl_Obj *pScript = 0;
  int rc;

  if( argc!=4 ){
    *pzErr = sqlite3_mprintf("wrong number of arguments");
    return SQLITE_ERROR;
  }
  zCmd = argv[3];


  pTab = (tcl_vtab*)sqlite3_malloc(sizeof(tcl_vtab));
  if( pTab==0 ) return SQLITE_NOMEM;


  memset(pTab, 0, sizeof(tcl_vtab));

  pTab->pCmd = Tcl_NewStringObj(zCmd, -1);
  pTab->interp = interp;
  pTab->db = db;
  Tcl_IncrRefCount(pTab->pCmd);

  pScript = Tcl_DuplicateObj(pTab->pCmd);
  Tcl_IncrRefCount(pScript);
  Tcl_ListObjAppendElement(interp, pScript, Tcl_NewStringObj("xConnect", -1));

  rc = Tcl_EvalObjEx(interp, pScript, TCL_EVAL_GLOBAL);
  if( rc!=TCL_OK ){
    *pzErr = sqlite3_mprintf("%s", Tcl_GetStringResult(interp));
    rc = SQLITE_ERROR;
  }else{
    rc = sqlite3_declare_vtab(db, Tcl_GetStringResult(interp));
  }

  if( rc!=SQLITE_OK ){
    sqlite3_free(pTab);
    pTab = 0;
  }





  *ppVtab = &pTab->base;
  return rc;
}

/* The xDisconnect and xDestroy methods are also the same */
static int tclDisconnect(sqlite3_vtab *pVtab){
  tcl_vtab *pTab = (tcl_vtab*)pVtab;
................................................................................
        }else
        if( sqlite3_stricmp("idxstr", zCmd)==0 ){
          sqlite3_free(pIdxInfo->idxStr);
          pIdxInfo->idxStr = sqlite3_mprintf("%s", Tcl_GetString(p));
          pIdxInfo->needToFreeIdxStr = 1;
        }else
        if( sqlite3_stricmp("rows", zCmd)==0 ){

          rc = Tcl_GetWideIntFromObj(interp, p, &pIdxInfo->estimatedRows);

        }else
        if( sqlite3_stricmp("use", zCmd)==0 
         || sqlite3_stricmp("omit", zCmd)==0 
        ){
          int iCons;
          rc = Tcl_GetIntFromObj(interp, p, &iCons);
          if( rc==SQLITE_OK ){

};

/* A tcl cursor object */
struct tcl_cursor {
  sqlite3_vtab_cursor base;
  sqlite3_stmt *pStmt;            /* Read data from here */
};

/*
** Dequote string z in place.
*/
static void tclDequote(char *z){
  char q = z[0];

  /* Set stack variable q to the close-quote character */
  if( q=='[' || q=='\'' || q=='"' || q=='`' ){
    int iIn = 1;
    int iOut = 0;
    if( q=='[' ) q = ']';  

    while( ALWAYS(z[iIn]) ){
      if( z[iIn]==q ){
        if( z[iIn+1]!=q ){
          /* Character iIn was the close quote. */
          iIn++;
          break;
        }else{
          /* Character iIn and iIn+1 form an escaped quote character. Skip
          ** the input cursor past both and copy a single quote character 
          ** to the output buffer. */
          iIn += 2;
          z[iOut++] = q;
        }
      }else{
        z[iOut++] = z[iIn++];
      }
    }

    z[iOut] = '\0';
  }
}

/*
** This function is the implementation of both the xConnect and xCreate
** methods of the fs virtual table.
**
** The argv[] array contains the following:
**
................................................................................
  sqlite3 *db,
  void *pAux,
  int argc, const char *const*argv,
  sqlite3_vtab **ppVtab,
  char **pzErr
){
  Tcl_Interp *interp = (Tcl_Interp*)pAux;
  tcl_vtab *pTab = 0;
  char *zCmd = 0;
  Tcl_Obj *pScript = 0;
  int rc = SQLITE_OK;

  if( argc!=4 ){
    *pzErr = sqlite3_mprintf("wrong number of arguments");
    return SQLITE_ERROR;
  }


  zCmd = sqlite3_malloc(strlen(argv[3])+1);
  pTab = (tcl_vtab*)sqlite3_malloc(sizeof(tcl_vtab));
  if( zCmd && pTab ){
    memcpy(zCmd, argv[3], strlen(argv[3])+1);
    tclDequote(zCmd);
    memset(pTab, 0, sizeof(tcl_vtab));

    pTab->pCmd = Tcl_NewStringObj(zCmd, -1);
    pTab->interp = interp;
    pTab->db = db;
    Tcl_IncrRefCount(pTab->pCmd);

    pScript = Tcl_DuplicateObj(pTab->pCmd);
    Tcl_IncrRefCount(pScript);
    Tcl_ListObjAppendElement(interp, pScript, Tcl_NewStringObj("xConnect", -1));

    rc = Tcl_EvalObjEx(interp, pScript, TCL_EVAL_GLOBAL);
    if( rc!=TCL_OK ){
      *pzErr = sqlite3_mprintf("%s", Tcl_GetStringResult(interp));
      rc = SQLITE_ERROR;
    }else{
      rc = sqlite3_declare_vtab(db, Tcl_GetStringResult(interp));
    }

    if( rc!=SQLITE_OK ){
      sqlite3_free(pTab);
      pTab = 0;
    }
  }else{
    rc = SQLITE_NOMEM;
  }

  sqlite3_free(zCmd);
  *ppVtab = &pTab->base;
  return rc;
}

/* The xDisconnect and xDestroy methods are also the same */
static int tclDisconnect(sqlite3_vtab *pVtab){
  tcl_vtab *pTab = (tcl_vtab*)pVtab;
................................................................................
        }else
        if( sqlite3_stricmp("idxstr", zCmd)==0 ){
          sqlite3_free(pIdxInfo->idxStr);
          pIdxInfo->idxStr = sqlite3_mprintf("%s", Tcl_GetString(p));
          pIdxInfo->needToFreeIdxStr = 1;
        }else
        if( sqlite3_stricmp("rows", zCmd)==0 ){
          Tcl_WideInt x = 0;
          rc = Tcl_GetWideIntFromObj(interp, p, &x);
          pIdxInfo->estimatedRows = (tRowcnt)x;
        }else
        if( sqlite3_stricmp("use", zCmd)==0 
         || sqlite3_stricmp("omit", zCmd)==0 
        ){
          int iCons;
          rc = Tcl_GetIntFromObj(interp, p, &iCons);
          if( rc==SQLITE_OK ){

/*
** Return the number of bytes that will be needed to store the given
** 64-bit integer.
*/
int sqlite3VarintLen(u64 v){
  int i;
  for(i=1; (v >>= 7)!=0; i++){ assert( i<9 ); }
  return i;
}


/*
** Read or write a four-byte big-endian integer value.
*/
................................................................................
  if( x<=2000000000 ) return sqlite3LogEst((u64)x);
  memcpy(&a, &x, 8);
  e = (a>>52) - 1022;
  return e*10;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */

#if defined(SQLITE_ENABLE_STMT_SCANSTAT) || \
    defined(SQLITE_ENABLE_STAT3_OR_STAT4) || \
    defined(SQLITE_EXPLAIN_ESTIMATED_ROWS)
/*
** Convert a LogEst into an integer.
**
** Note that this routine is only used when one or more of various
** non-standard compile-time options is enabled.

/*
** Return the number of bytes that will be needed to store the given
** 64-bit integer.
*/
int sqlite3VarintLen(u64 v){
  int i;
  for(i=1; (v >>= 7)!=0; i++){ assert( i<10 ); }
  return i;
}


/*
** Read or write a four-byte big-endian integer value.
*/
................................................................................
  if( x<=2000000000 ) return sqlite3LogEst((u64)x);
  memcpy(&a, &x, 8);
  e = (a>>52) - 1022;
  return e*10;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */

#if defined(SQLITE_ENABLE_STMT_SCANSTATUS) || \
    defined(SQLITE_ENABLE_STAT3_OR_STAT4) || \
    defined(SQLITE_EXPLAIN_ESTIMATED_ROWS)
/*
** Convert a LogEst into an integer.
**
** Note that this routine is only used when one or more of various
** non-standard compile-time options is enabled.

    ** considered. */
    if( pSrc->pIBIndex ) break;
  }
  return rc;
}

#ifndef SQLITE_OMIT_VIRTUALTABLE

















































































































































/*
** Add all WhereLoop objects for a table of the join identified by
** pBuilder->pNew->iTab.  That table is guaranteed to be a virtual table.
**
** If there are no LEFT or CROSS JOIN joins in the query, both mExtra and
** mUnusable are set to 0. Otherwise, mExtra is a mask of all FROM clause
** entries that occur before the virtual table in the FROM clause and are
................................................................................
** mUnusable should always be configured as "not-usable" for xBestIndex.
*/
static int whereLoopAddVirtual(
  WhereLoopBuilder *pBuilder,  /* WHERE clause information */
  Bitmask mExtra,              /* Tables that must be scanned before this one */
  Bitmask mUnusable            /* Tables that must be scanned after this one */
){

  WhereInfo *pWInfo;           /* WHERE analysis context */
  Parse *pParse;               /* The parsing context */
  WhereClause *pWC;            /* The WHERE clause */
  struct SrcList_item *pSrc;   /* The FROM clause term to search */
  Table *pTab;
  sqlite3 *db;
  sqlite3_index_info *pIdxInfo;
  struct sqlite3_index_constraint *pIdxCons;
  struct sqlite3_index_constraint_usage *pUsage;
  WhereTerm *pTerm;
  int i, j;
  int iTerm, mxTerm;
  int nConstraint;
  int seenIn = 0;              /* True if an IN operator is seen */
  int seenVar = 0;             /* True if a non-constant constraint is seen */
  int iPhase;                  /* 0: const w/o IN, 1: const, 2: no IN,  2: IN */

  WhereLoop *pNew;
  int rc = SQLITE_OK;


  assert( (mExtra & mUnusable)==0 );
  pWInfo = pBuilder->pWInfo;
  pParse = pWInfo->pParse;
  db = pParse->db;
  pWC = pBuilder->pWC;
  pNew = pBuilder->pNew;
  pSrc = &pWInfo->pTabList->a[pNew->iTab];
  pTab = pSrc->pTab;
  assert( IsVirtual(pTab) );
  pIdxInfo = allocateIndexInfo(pParse, pWC, mUnusable, pSrc,pBuilder->pOrderBy);
  if( pIdxInfo==0 ) return SQLITE_NOMEM_BKPT;
  pNew->prereq = 0;
  pNew->rSetup = 0;
  pNew->wsFlags = WHERE_VIRTUALTABLE;
  pNew->nLTerm = 0;
  pNew->u.vtab.needFree = 0;
  pUsage = pIdxInfo->aConstraintUsage;
  nConstraint = pIdxInfo->nConstraint;
  if( whereLoopResize(db, pNew, nConstraint) ){
    sqlite3DbFree(db, pIdxInfo);
    return SQLITE_NOMEM_BKPT;
  }

  for(iPhase=0; iPhase<=3; iPhase++){
    if( !seenIn && (iPhase&1)!=0 ){
      iPhase++;
      if( iPhase>3 ) break;
    }
    if( !seenVar && iPhase>1 ) break;
    pIdxCons = *(struct sqlite3_index_constraint**)&pIdxInfo->aConstraint;
    for(i=0; i<pIdxInfo->nConstraint; i++, pIdxCons++){
      j = pIdxCons->iTermOffset;
      pTerm = &pWC->a[j];
      switch( iPhase ){
        case 0:    /* Constants without IN operator */
          pIdxCons->usable = 0;
          if( (pTerm->eOperator & WO_IN)!=0 ){
            seenIn = 1;
          }
          if( (pTerm->prereqRight & ~mExtra)!=0 ){
            seenVar = 1;
          }else if( (pTerm->eOperator & WO_IN)==0 ){
            pIdxCons->usable = 1;
          }
          break;
        case 1:    /* Constants with IN operators */
          assert( seenIn );
          pIdxCons->usable = (pTerm->prereqRight & ~mExtra)==0;
          break;
        case 2:    /* Variables without IN */
          assert( seenVar );
          pIdxCons->usable = (pTerm->eOperator & WO_IN)==0;
          break;
        default:   /* Variables with IN */
          assert( seenVar && seenIn );
          pIdxCons->usable = 1;
          break;
      }
    }
    memset(pUsage, 0, sizeof(pUsage[0])*pIdxInfo->nConstraint);
    if( pIdxInfo->needToFreeIdxStr ) sqlite3_free(pIdxInfo->idxStr);
    pIdxInfo->idxStr = 0;
    pIdxInfo->idxNum = 0;
    pIdxInfo->needToFreeIdxStr = 0;
    pIdxInfo->orderByConsumed = 0;
    pIdxInfo->estimatedCost = SQLITE_BIG_DBL / (double)2;
    pIdxInfo->estimatedRows = 25;
    pIdxInfo->idxFlags = 0;
    pIdxInfo->colUsed = (sqlite3_int64)pSrc->colUsed;
    rc = vtabBestIndex(pParse, pTab, pIdxInfo);
    if( rc ) goto whereLoopAddVtab_exit;
    pIdxCons = *(struct sqlite3_index_constraint**)&pIdxInfo->aConstraint;
    pNew->prereq = mExtra;
    mxTerm = -1;
    assert( pNew->nLSlot>=nConstraint );
    for(i=0; i<nConstraint; i++) pNew->aLTerm[i] = 0;
    pNew->u.vtab.omitMask = 0;
    for(i=0; i<nConstraint; i++, pIdxCons++){
      if( (iTerm = pUsage[i].argvIndex - 1)>=0 ){
        j = pIdxCons->iTermOffset;
        if( iTerm>=nConstraint
         || j<0
         || j>=pWC->nTerm
         || pNew->aLTerm[iTerm]!=0
        ){
          rc = SQLITE_ERROR;
          sqlite3ErrorMsg(pParse, "%s.xBestIndex() malfunction", pTab->zName);
          goto whereLoopAddVtab_exit;
        }
        testcase( iTerm==nConstraint-1 );
        testcase( j==0 );
        testcase( j==pWC->nTerm-1 );
        pTerm = &pWC->a[j];
        pNew->prereq |= pTerm->prereqRight;
        assert( iTerm<pNew->nLSlot );
        pNew->aLTerm[iTerm] = pTerm;
        if( iTerm>mxTerm ) mxTerm = iTerm;
        testcase( iTerm==15 );
        testcase( iTerm==16 );
        if( iTerm<16 && pUsage[i].omit ) pNew->u.vtab.omitMask |= 1<<iTerm;
        if( (pTerm->eOperator & WO_IN)!=0 ){
          /* A virtual table that is constrained by an IN clause may not
          ** consume the ORDER BY clause because (1) the order of IN terms
          ** is not necessarily related to the order of output terms and
          ** (2) Multiple outputs from a single IN value will not merge
          ** together.  */
          pIdxInfo->orderByConsumed = 0;
          pIdxInfo->idxFlags &= ~SQLITE_INDEX_SCAN_UNIQUE;
        }
      }
    }
    if( i>=nConstraint ){
      pNew->nLTerm = mxTerm+1;
      assert( pNew->nLTerm<=pNew->nLSlot );
      pNew->u.vtab.idxNum = pIdxInfo->idxNum;
      pNew->u.vtab.needFree = pIdxInfo->needToFreeIdxStr;
      pIdxInfo->needToFreeIdxStr = 0;
      pNew->u.vtab.idxStr = pIdxInfo->idxStr;
      pNew->u.vtab.isOrdered = (i8)(pIdxInfo->orderByConsumed ?
                                      pIdxInfo->nOrderBy : 0);
      pNew->rSetup = 0;
      pNew->rRun = sqlite3LogEstFromDouble(pIdxInfo->estimatedCost);
      pNew->nOut = sqlite3LogEst(pIdxInfo->estimatedRows);

      /* Set the WHERE_ONEROW flag if the xBestIndex() method indicated
      ** that the scan will visit at most one row. Clear it otherwise. */
      if( pIdxInfo->idxFlags & SQLITE_INDEX_SCAN_UNIQUE ){
        pNew->wsFlags |= WHERE_ONEROW;
      }else{
        pNew->wsFlags &= ~WHERE_ONEROW;
      }
      whereLoopInsert(pBuilder, pNew);
      if( pNew->u.vtab.needFree ){
        sqlite3_free(pNew->u.vtab.idxStr);
        pNew->u.vtab.needFree = 0;
      }
    }
  }  

whereLoopAddVtab_exit:
  if( pIdxInfo->needToFreeIdxStr ) sqlite3_free(pIdxInfo->idxStr);
  sqlite3DbFree(db, pIdxInfo);
  return rc;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */

/*
** Add WhereLoop entries to handle OR terms.  This works for either
** btrees or virtual tables.

    ** considered. */
    if( pSrc->pIBIndex ) break;
  }
  return rc;
}

#ifndef SQLITE_OMIT_VIRTUALTABLE

/*
** Argument pIdxInfo is already populated with all constraints that may
** be used by the virtual table identified by pBuilder->pNew->iTab. This
** function marks a subset of those constraints usable, invokes the
** xBestIndex method and adds the returned plan to pBuilder.
**
** A constraint is marked usable if:
**
**   * Argument mUsable indicates that its prerequisites are available, and
**
**   * It is not one of the operators specified in the mExclude mask passed
**     as the fourth argument (which in practice is either WO_IN or 0).
**
** Argument mExtra is a mask of tables that must be scanned before the
** virtual table in question. These are added to the plans prerequisites
** before it is added to pBuilder.
**
** Output parameter *pbIn is set to true if the plan added to pBuilder
** uses one or more WO_IN terms, or false otherwise.
*/
static int whereLoopAddVirtualOne(
  WhereLoopBuilder *pBuilder,
  Bitmask mExtra,                 /* Mask of tables that must be used. */
  Bitmask mUsable,                /* Mask of usable prereqs */
  u16 mExclude,                   /* Exclude terms for this operator */
  sqlite3_index_info *pIdxInfo,   /* Populated object for xBestIndex */
  int *pbIn                       /* OUT: True if plan uses an IN(...) op */
){
  WhereClause *pWC = pBuilder->pWC;
  struct sqlite3_index_constraint *pIdxCons;
  struct sqlite3_index_constraint_usage *pUsage = pIdxInfo->aConstraintUsage;
  int i;
  int mxTerm;
  int rc = SQLITE_OK;
  WhereLoop *pNew = pBuilder->pNew;
  Parse *pParse = pBuilder->pWInfo->pParse;
  struct SrcList_item *pSrc = &pBuilder->pWInfo->pTabList->a[pNew->iTab];
  int nConstraint = pIdxInfo->nConstraint;

  assert( (mUsable & mExtra)==mExtra );
  *pbIn = 0;
  pNew->prereq = mExtra;

  /* Set the usable flag on the subset of constraints identified by 
  ** arguments mUsable and mExclude. */
  pIdxCons = *(struct sqlite3_index_constraint**)&pIdxInfo->aConstraint;
  for(i=0; i<nConstraint; i++, pIdxCons++){
    WhereTerm *pTerm = &pWC->a[pIdxCons->iTermOffset];
    pIdxCons->usable = 0;
    if( (pTerm->prereqRight & mUsable)==pTerm->prereqRight 
     && (pTerm->eOperator & mExclude)==0
    ){
      pIdxCons->usable = 1;
    }
  }

  /* Initialize the output fields of the sqlite3_index_info structure */
  memset(pUsage, 0, sizeof(pUsage[0])*nConstraint);
  if( pIdxInfo->needToFreeIdxStr ) sqlite3_free(pIdxInfo->idxStr);
  pIdxInfo->idxStr = 0;
  pIdxInfo->idxNum = 0;
  pIdxInfo->needToFreeIdxStr = 0;
  pIdxInfo->orderByConsumed = 0;
  pIdxInfo->estimatedCost = SQLITE_BIG_DBL / (double)2;
  pIdxInfo->estimatedRows = 25;
  pIdxInfo->idxFlags = 0;
  pIdxInfo->colUsed = (sqlite3_int64)pSrc->colUsed;

  /* Invoke the virtual table xBestIndex() method */
  rc = vtabBestIndex(pParse, pSrc->pTab, pIdxInfo);
  if( rc ) return rc;

  mxTerm = -1;
  assert( pNew->nLSlot>=nConstraint );
  for(i=0; i<nConstraint; i++) pNew->aLTerm[i] = 0;
  pNew->u.vtab.omitMask = 0;
  pIdxCons = *(struct sqlite3_index_constraint**)&pIdxInfo->aConstraint;
  for(i=0; i<nConstraint; i++, pIdxCons++){
    int iTerm;
    if( (iTerm = pUsage[i].argvIndex - 1)>=0 ){
      WhereTerm *pTerm;
      int j = pIdxCons->iTermOffset;
      if( iTerm>=nConstraint
       || j<0
       || j>=pWC->nTerm
       || pNew->aLTerm[iTerm]!=0
      ){
        rc = SQLITE_ERROR;
        sqlite3ErrorMsg(pParse,"%s.xBestIndex() malfunction",pSrc->pTab->zName);
        return rc;
      }
      testcase( iTerm==nConstraint-1 );
      testcase( j==0 );
      testcase( j==pWC->nTerm-1 );
      pTerm = &pWC->a[j];
      pNew->prereq |= pTerm->prereqRight;
      assert( iTerm<pNew->nLSlot );
      pNew->aLTerm[iTerm] = pTerm;
      if( iTerm>mxTerm ) mxTerm = iTerm;
      testcase( iTerm==15 );
      testcase( iTerm==16 );
      if( iTerm<16 && pUsage[i].omit ) pNew->u.vtab.omitMask |= 1<<iTerm;
      if( (pTerm->eOperator & WO_IN)!=0 ){
        /* A virtual table that is constrained by an IN clause may not
        ** consume the ORDER BY clause because (1) the order of IN terms
        ** is not necessarily related to the order of output terms and
        ** (2) Multiple outputs from a single IN value will not merge
        ** together.  */
        pIdxInfo->orderByConsumed = 0;
        pIdxInfo->idxFlags &= ~SQLITE_INDEX_SCAN_UNIQUE;
        *pbIn = 1;
      }
    }
  }

  pNew->nLTerm = mxTerm+1;
  assert( pNew->nLTerm<=pNew->nLSlot );
  pNew->u.vtab.idxNum = pIdxInfo->idxNum;
  pNew->u.vtab.needFree = pIdxInfo->needToFreeIdxStr;
  pIdxInfo->needToFreeIdxStr = 0;
  pNew->u.vtab.idxStr = pIdxInfo->idxStr;
  pNew->u.vtab.isOrdered = (i8)(pIdxInfo->orderByConsumed ?
      pIdxInfo->nOrderBy : 0);
  pNew->rSetup = 0;
  pNew->rRun = sqlite3LogEstFromDouble(pIdxInfo->estimatedCost);
  pNew->nOut = sqlite3LogEst(pIdxInfo->estimatedRows);

  /* Set the WHERE_ONEROW flag if the xBestIndex() method indicated
  ** that the scan will visit at most one row. Clear it otherwise. */
  if( pIdxInfo->idxFlags & SQLITE_INDEX_SCAN_UNIQUE ){
    pNew->wsFlags |= WHERE_ONEROW;
  }else{
    pNew->wsFlags &= ~WHERE_ONEROW;
  }
  whereLoopInsert(pBuilder, pNew);
  if( pNew->u.vtab.needFree ){
    sqlite3_free(pNew->u.vtab.idxStr);
    pNew->u.vtab.needFree = 0;
  }

  return SQLITE_OK;
}


/*
** Add all WhereLoop objects for a table of the join identified by
** pBuilder->pNew->iTab.  That table is guaranteed to be a virtual table.
**
** If there are no LEFT or CROSS JOIN joins in the query, both mExtra and
** mUnusable are set to 0. Otherwise, mExtra is a mask of all FROM clause
** entries that occur before the virtual table in the FROM clause and are
................................................................................
** mUnusable should always be configured as "not-usable" for xBestIndex.
*/
static int whereLoopAddVirtual(
  WhereLoopBuilder *pBuilder,  /* WHERE clause information */
  Bitmask mExtra,              /* Tables that must be scanned before this one */
  Bitmask mUnusable            /* Tables that must be scanned after this one */
){
  int rc = SQLITE_OK;          /* Return code */
  WhereInfo *pWInfo;           /* WHERE analysis context */
  Parse *pParse;               /* The parsing context */
  WhereClause *pWC;            /* The WHERE clause */
  struct SrcList_item *pSrc;   /* The FROM clause term to search */


  sqlite3_index_info *p;       /* Object to pass to xBestIndex() */





  int nConstraint;             /* Number of constraints in p */



  int bIn;                     /* True if plan uses IN(...) operator */
  WhereLoop *pNew;

  Bitmask mBest;               /* Tables used by best possible plan */

  assert( (mExtra & mUnusable)==0 );
  pWInfo = pBuilder->pWInfo;
  pParse = pWInfo->pParse;

  pWC = pBuilder->pWC;
  pNew = pBuilder->pNew;
  pSrc = &pWInfo->pTabList->a[pNew->iTab];

  assert( IsVirtual(pSrc->pTab) );
  p = allocateIndexInfo(pParse, pWC, mUnusable, pSrc,pBuilder->pOrderBy);
  if( p==0 ) return SQLITE_NOMEM_BKPT;

  pNew->rSetup = 0;
  pNew->wsFlags = WHERE_VIRTUALTABLE;
  pNew->nLTerm = 0;
  pNew->u.vtab.needFree = 0;
  nConstraint = p->nConstraint;
  if( whereLoopResize(pParse->db, pNew, nConstraint) ){
    sqlite3DbFree(pParse->db, p);
    return SQLITE_NOMEM_BKPT;
  }

  /* First call xBestIndex() with all constraints usable. */
  rc = whereLoopAddVirtualOne(pBuilder, mExtra, (Bitmask)(-1), 0, p, &bIn);
  mBest = pNew->prereq & ~mExtra;

  /* If the call to xBestIndex() with all terms enabled produced a plan
  ** that does not require any source tables, there is no point in making
  ** any further calls - if the xBestIndex() method is sane they will all
  ** return the same plan anyway.
  */
  if( mBest ){
    int seenZero = 0;             /* True if a plan with no prereqs seen */
    int seenZeroNoIN = 0;         /* Plan with no prereqs and no IN(...) seen */
    Bitmask mPrev = 0;
    Bitmask mBestNoIn = 0;

    /* If the plan produced by the earlier call uses an IN(...) term, call
    ** xBestIndex again, this time with IN(...) terms disabled. */
    if( rc==SQLITE_OK && bIn ){
      rc = whereLoopAddVirtualOne(pBuilder, mExtra, (Bitmask)-1, WO_IN, p,&bIn);
      mBestNoIn = pNew->prereq & ~mExtra;
      if( mBestNoIn==0 ){
        seenZero = 1;
        if( bIn==0 ) seenZeroNoIN = 1;
      }
    }

    /* Call xBestIndex once for each distinct value of (prereqRight & ~mExtra) 
    ** in the set of terms that apply to the current virtual table.  */
    while( rc==SQLITE_OK ){
      int i;
      Bitmask mNext = (Bitmask)(-1);
      assert( mNext>0 );
      for(i=0; i<nConstraint; i++){
        Bitmask mThis = (
            pWC->a[p->aConstraint[i].iTermOffset].prereqRight & ~mExtra
        );
        if( mThis>mPrev && mThis<mNext ) mNext = mThis;
      }
      mPrev = mNext;
      if( mNext==(Bitmask)(-1) ) break;
      if( mNext==mBest || mNext==mBestNoIn ) continue;
      rc = whereLoopAddVirtualOne(pBuilder, mExtra, mNext|mExtra, 0, p, &bIn);
      if( pNew->prereq==mExtra ){
        seenZero = 1;
        if( bIn==0 ) seenZeroNoIN = 1;
      }
    }

    /* If the calls to xBestIndex() in the above loop did not find a plan
    ** that requires no source tables at all (i.e. one guaranteed to be
    ** usable), make a call here with all source tables disabled */
    if( rc==SQLITE_OK && seenZero==0 ){
      rc = whereLoopAddVirtualOne(pBuilder, mExtra, mExtra, 0, p, &bIn);
      if( bIn==0 ) seenZeroNoIN = 1;
    }

    /* If the calls to xBestIndex() have so far failed to find a plan
    ** that requires no source tables at all and does not use an IN(...)
    ** operator, make a final call to obtain one here.  */
    if( rc==SQLITE_OK && seenZeroNoIN==0 ){
      rc = whereLoopAddVirtualOne(pBuilder, mExtra, mExtra, WO_IN, p, &bIn);
    }
  }

  if( p->needToFreeIdxStr ) sqlite3_free(p->idxStr);
  sqlite3DbFree(pParse->db, p);






















































  return rc;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */

/*
** Add WhereLoop entries to handle OR terms.  This works for either
** btrees or virtual tables.

        /* Generate code that will continue to the next row if 
        ** the IN constraint is not satisfied */
        pCompare = sqlite3PExpr(pParse, TK_EQ, 0, 0, 0);
        assert( pCompare!=0 || db->mallocFailed );
        if( pCompare ){
          pCompare->pLeft = pTerm->pExpr->pLeft;
          pCompare->pRight = pRight = sqlite3Expr(db, TK_REGISTER, 0);

          if( pRight ) pRight->iTable = iReg+j+2;
          sqlite3ExprIfFalse(pParse, pCompare, pLevel->addrCont, 0);

          pCompare->pLeft = 0;
          sqlite3ExprDelete(db, pCompare);
        }
      }
    }
    sqlite3ReleaseTempRange(pParse, iReg, nConstraint+2);
    sqlite3ExprCachePop(pParse);

        /* Generate code that will continue to the next row if 
        ** the IN constraint is not satisfied */
        pCompare = sqlite3PExpr(pParse, TK_EQ, 0, 0, 0);
        assert( pCompare!=0 || db->mallocFailed );
        if( pCompare ){
          pCompare->pLeft = pTerm->pExpr->pLeft;
          pCompare->pRight = pRight = sqlite3Expr(db, TK_REGISTER, 0);
          if( pRight ){
            pRight->iTable = iReg+j+2;
            sqlite3ExprIfFalse(pParse, pCompare, pLevel->addrCont, 0);
          }
          pCompare->pLeft = 0;
          sqlite3ExprDelete(db, pCompare);
        }
      }
    }
    sqlite3ReleaseTempRange(pParse, iReg, nConstraint+2);
    sqlite3ExprCachePop(pParse);

# 2016 March 3
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix bestindex2


#-------------------------------------------------------------------------
# Virtual table callback for table named $tbl, with the columns specified
# by list argument $cols. e.g. if the function is invoked as:
#
#   vtab_cmd t1 {a b c} ...
#
# The table created is:
#
#      "CREATE TABLE t1 (a, b, c)"
#
# The tables xBestIndex method behaves as if all possible combinations of
# "=" constraints (but no others) may be optimized. The cost of a full table
# scan is:
#
#      "WHERE 1"                "cost 1000000 rows 1000000"
#
# If one or more "=" constraints are in use, the cost and estimated number
# of rows returned are both is (11 - nCons)*1000, where nCons is the number
# of constraints used. e.g.
#
#   "WHERE a=? AND b=?"    ->   "cost  900 rows  900"
#   "WHERE c=? AND b<?"    ->   "cost 1000 rows 1000"
#  
proc vtab_cmd {tbl cols method args} {
  switch -- $method {
    xConnect {
      return "CREATE TABLE $tbl ([join $cols ,])"
    }
    xBestIndex {
      foreach {clist orderby mask} $args {}

      set cons [list]
      set used [list]

      for {set i 0} {$i < [llength $clist]} {incr i} {
        array unset C
        array set C [lindex $clist $i]
        if {$C(op)=="eq" && $C(usable) && [lsearch $cons $C(column)]<0} {
          lappend used use $i
          lappend cons $C(column)
        }
      }

      set nCons [llength $cons]
      if {$nCons==0} {
        return "cost 1000000 rows 1000000"
      } else {
        set cost [expr (11-$nCons) * 1000]
        set ret [concat $used "cost $cost rows $cost"]

        set txt [list]
        foreach c $cons { lappend txt "[lindex $cols $c]=?" }
        lappend ret idxstr "indexed([join $txt { AND }])"

        return $ret
      }
    }
  }
  return ""
}

register_tcl_module db

do_execsql_test 1.0 {
  CREATE VIRTUAL TABLE t1 USING tcl("vtab_cmd t1 {a b}");
  CREATE VIRTUAL TABLE t2 USING tcl("vtab_cmd t2 {c d}");
  CREATE VIRTUAL TABLE t3 USING tcl("vtab_cmd t3 {e f}");
}

do_eqp_test 1.1 {
  SELECT * FROM t1 WHERE a='abc'
} {
  0 0 0 {SCAN TABLE t1 VIRTUAL TABLE INDEX 0:indexed(a=?)}
}
do_eqp_test 1.2 {
  SELECT * FROM t1 WHERE a='abc' AND b='def'
} {
  0 0 0 {SCAN TABLE t1 VIRTUAL TABLE INDEX 0:indexed(a=? AND b=?)}
}
do_eqp_test 1.3 {
  SELECT * FROM t1 WHERE a='abc' AND a='def'
} {
  0 0 0 {SCAN TABLE t1 VIRTUAL TABLE INDEX 0:indexed(a=?)}
}
do_eqp_test 1.4 {
  SELECT * FROM t1,t2 WHERE c=a
} {
  0 0 0 {SCAN TABLE t1 VIRTUAL TABLE INDEX 0:} 
  0 1 1 {SCAN TABLE t2 VIRTUAL TABLE INDEX 0:indexed(c=?)}
}

do_eqp_test 1.5 {
  SELECT * FROM t1, t2 CROSS JOIN t3 WHERE t2.c = +t1.b AND t3.e=t2.d
} {
  0 0 0 {SCAN TABLE t1 VIRTUAL TABLE INDEX 0:} 
  0 1 1 {SCAN TABLE t2 VIRTUAL TABLE INDEX 0:indexed(c=?)} 
  0 2 2 {SCAN TABLE t3 VIRTUAL TABLE INDEX 0:indexed(e=?)}
}

do_eqp_test 1.6 {
  SELECT * FROM t1, t2, t3 WHERE t2.c = +t1.b AND t3.e = t2.d
} {
  0 0 0 {SCAN TABLE t1 VIRTUAL TABLE INDEX 0:} 
  0 1 1 {SCAN TABLE t2 VIRTUAL TABLE INDEX 0:indexed(c=?)} 
  0 2 2 {SCAN TABLE t3 VIRTUAL TABLE INDEX 0:indexed(e=?)}
}

do_execsql_test 1.7.1 {
  CREATE TABLE x1(a, b);
}
do_eqp_test 1.7.2 {
  SELECT * FROM x1 CROSS JOIN t1, t2, t3 
    WHERE t1.a = t2.c AND t1.b = t3.e
} {
  0 0 0 {SCAN TABLE x1} 
  0 1 1 {SCAN TABLE t1 VIRTUAL TABLE INDEX 0:}
  0 2 2 {SCAN TABLE t2 VIRTUAL TABLE INDEX 0:indexed(c=?)} 
  0 3 3 {SCAN TABLE t3 VIRTUAL TABLE INDEX 0:indexed(e=?)}
}

finish_test

    1   {merge=abc}
    2   {merge=%%%}
    3   {merge=,}
    4   {merge=5,}
    5   {merge=6,%}
    6   {merge=6,six}
    7   {merge=6,1}
    8   {merge=6,0}
  } {
    do_catchsql_test 2.$tn { 
      INSERT INTO t2(t2) VALUES($arg);
    } {1 {SQL logic error or missing database}}
  }
  
  #-------------------------------------------------------------------------

    1   {merge=abc}
    2   {merge=%%%}
    3   {merge=,}
    4   {merge=5,}
    5   {merge=6,%}
    6   {merge=6,six}
    7   {merge=6,1}

  } {
    do_catchsql_test 2.$tn { 
      INSERT INTO t2(t2) VALUES($arg);
    } {1 {SQL logic error or missing database}}
  }
  
  #-------------------------------------------------------------------------

# 2016 March 8
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#*************************************************************************
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
source $testdir/fts3_common.tcl
set ::testprefix fts4opt

# If SQLITE_ENABLE_FTS3 is defined, omit this file.
ifcapable !fts3 {
  finish_test
  return
}

# Create the fts_kjv_genesis procedure which fills and FTS3/4 table 
# with the complete text of the Book of Genesis.
#
source $testdir/genesis.tcl

do_execsql_test 1.0 { CREATE TABLE t1(docid, words) }
fts_kjv_genesis

#-------------------------------------------------------------------------
# Argument $db is an open database handle. $tbl is the name of an FTS3/4
# table with the database. This command rearranges the contents of the
# %_segdir table so that all segments within each index are on the same
# level. This means that the 'merge' command can then be used for an
# incremental optimize routine.
#
proc prepare_for_optimize {db tbl} {
  $db eval [string map [list % $tbl] {
    BEGIN;
      CREATE TEMP TABLE tmp_segdir(
        level, idx, start_block, leaves_end_block, end_block, root
      );

      INSERT INTO temp.tmp_segdir 
        SELECT 
        1024*(o.level / 1024) + 32,                                -- level
        sum(o.level<i.level OR (o.level=i.level AND o.idx>i.idx)), -- idx
        o.start_block, o.leaves_end_block, o.end_block, o.root     -- other
        FROM %_segdir o, %_segdir i 
        WHERE (o.level / 1024) = (i.level / 1024)
        GROUP BY o.level, o.idx;
  
      DELETE FROM %_segdir;
      INSERT INTO %_segdir SELECT * FROM temp.tmp_segdir;
      DROP TABLE temp.tmp_segdir;
  
    COMMIT;
  }]
}

do_test 1.1 {
  execsql { CREATE VIRTUAL TABLE t2 USING fts4(words, prefix="1,2,3") }
  foreach {docid words} [db eval { SELECT * FROM t1 }] {
    execsql { INSERT INTO t2(docid, words) VALUES($docid, $words) }
  }
} {}

do_execsql_test 1.2 {
  SELECT level, count(*) FROM t2_segdir GROUP BY level
} {
  0    13    1 15    2 5 
  1024 13 1025 15 1026 5 
  2048 13 2049 15 2050 5 
  3072 13 3073 15 3074 5
}

do_execsql_test 1.3 { INSERT INTO t2(t2) VALUES('integrity-check') }
prepare_for_optimize db t2
do_execsql_test 1.4 { INSERT INTO t2(t2) VALUES('integrity-check') }

do_execsql_test 1.5 {
  SELECT level, count(*) FROM t2_segdir GROUP BY level
} {
  32   33 
  1056 33 
  2080 33 
  3104 33
}

do_test 1.6 {
  while 1 {
    set tc1 [db total_changes]
    execsql { INSERT INTO t2(t2) VALUES('merge=5,0') }
    set tc2 [db total_changes]
    if {($tc2 - $tc1) < 2} break
  }
  execsql { SELECT level, count(*) FROM t2_segdir GROUP BY level }
} {33 1 1057 1 2081 1 3105 1}
do_execsql_test 1.7 { INSERT INTO t2(t2) VALUES('integrity-check') }

do_execsql_test 1.8 {
  INSERT INTO t2(words) SELECT words FROM t1;
  SELECT level, count(*) FROM t2_segdir GROUP BY level;
} {0 2 1024 2 2048 2 3072 2}

#-------------------------------------------------------------------------

do_execsql_test 2.0 {
  DELETE FROM t2;
}
do_test 2.1 {
  foreach {docid words} [db eval { SELECT * FROM t1 }] {
    execsql { INSERT INTO t2(docid, words) VALUES($docid, $words) }
  }

  set i 0
  foreach {docid words} [db eval { SELECT * FROM t1 }] {
    if {[incr i] % 2} { execsql { DELETE FROM t2 WHERE docid = $docid } }
  }

  set i 0
  foreach {docid words} [db eval { SELECT * FROM t1 }] {
    if {[incr i] % 3} {
      execsql { INSERT OR REPLACE INTO t2(docid, words) VALUES($docid, $words) }
    }
  }
} {}

do_execsql_test 2.2 {
  SELECT level, count(*) FROM t2_segdir GROUP BY level
} {
  0    10    1 15    2 12 
  1024 10 1025 15 1026 12 
  2048 10 2049 15 2050 12 
  3072 10 3073 15 3074 12
}

do_execsql_test 2.3 { INSERT INTO t2(t2) VALUES('integrity-check') }
prepare_for_optimize db t2
do_execsql_test 2.4 { INSERT INTO t2(t2) VALUES('integrity-check') }

do_execsql_test 2.5 {
  SELECT level, count(*) FROM t2_segdir GROUP BY level
} {
    32 37 
  1056 37 
  2080 37 
  3104 37
}

do_test 2.6 {
  while 1 {
    set tc1 [db total_changes]
    execsql { INSERT INTO t2(t2) VALUES('merge=5,0') }
    set tc2 [db total_changes]
    if {($tc2 - $tc1) < 2} break
  }
  execsql { SELECT level, count(*) FROM t2_segdir GROUP BY level }
} {33 1 1057 1 2081 1 3105 1}
do_execsql_test 2.7 { INSERT INTO t2(t2) VALUES('integrity-check') }

do_execsql_test 2.8 {
  INSERT INTO t2(words) SELECT words FROM t1;
  SELECT level, count(*) FROM t2_segdir GROUP BY level;
} {0 2 1024 2 2048 2 3072 2}

finish_test

   vdbemem.c
   vdbeaux.c
   vdbeapi.c
   vdbetrace.c
   vdbe.c
   vdbeblob.c
   vdbesort.c
   journal.c
   memjournal.c

   walker.c
   resolve.c
   expr.c
   alter.c
   analyze.c

   vdbemem.c
   vdbeaux.c
   vdbeapi.c
   vdbetrace.c
   vdbe.c
   vdbeblob.c
   vdbesort.c

   memjournal.c

   walker.c
   resolve.c
   expr.c
   alter.c
   analyze.c