SQLite

** If successful, SQLITE_OK is returned. Otherwise, an SQLite error code.
*/
static int fts3PendingTermsAdd(
  Fts3Table *p,                   /* Table into which text will be inserted */
  int iLangid,                    /* Language id to use */
  const char *zText,              /* Text of document to be inserted */
  int iCol,                       /* Column into which text is being inserted */
  u32 *pnWord                     /* IN/OUT: Incr. by number tokens inserted */
){
  int rc;
  int iStart = 0;
  int iEnd = 0;
  int iPos = 0;
  int nWord = 0;

      rc = fts3PendingTermsAddOne(
          p, iCol, iPos, &pIndex->hPending, zToken, pIndex->nPrefix
      );
    }
  }

  pModule->xClose(pCsr);
  *pnWord += nWord;
  return (rc==SQLITE_DONE ? SQLITE_OK : rc);
}

/* 
** Calling this function indicates that subsequent calls to 
** fts3PendingTermsAdd() are to add term/position-list pairs for the
** contents of the document with docid iDocid.

** (an integer) of a row about to be deleted. Remove all terms from the
** full-text index.
*/
static void fts3DeleteTerms( 
  int *pRC,               /* Result code */
  Fts3Table *p,           /* The FTS table to delete from */
  sqlite3_value *pRowid,  /* The docid to be deleted */
  u32 *aSz,               /* Sizes of deleted document written here */
  int *pbFound            /* OUT: Set to true if row really does exist */
){
  int rc;
  sqlite3_stmt *pSelect;

  assert( *pbFound==0 );
  if( *pRC ) return;
  rc = fts3SqlStmt(p, SQL_SELECT_CONTENT_BY_ROWID, &pSelect, &pRowid);
  if( rc==SQLITE_OK ){
    if( SQLITE_ROW==sqlite3_step(pSelect) ){
      int i;
      int iLangid = langidFromSelect(p, pSelect);
      rc = fts3PendingTermsDocid(p, iLangid, sqlite3_column_int64(pSelect, 0));
      for(i=1; rc==SQLITE_OK && i<=p->nColumn; i++){
        const char *zText = (const char *)sqlite3_column_text(pSelect, i);
        rc = fts3PendingTermsAdd(p, iLangid, zText, -1, &aSz[i-1]);
        aSz[p->nColumn] += sqlite3_column_bytes(pSelect, i);
      }
      if( rc!=SQLITE_OK ){
        sqlite3_reset(pSelect);
        *pRC = rc;
        return;
      }
      *pbFound = 1;
    }
    rc = sqlite3_reset(pSelect);
  }else{
    sqlite3_reset(pSelect);
  }
  *pRC = rc;
}

      }
    }

    while( rc==SQLITE_OK && SQLITE_ROW==sqlite3_step(pStmt) ){
      int iCol;
      int iLangid = langidFromSelect(p, pStmt);
      rc = fts3PendingTermsDocid(p, iLangid, sqlite3_column_int64(pStmt, 0));
      memset(aSz, 0, sizeof(aSz[0]) * (p->nColumn+1));
      for(iCol=0; rc==SQLITE_OK && iCol<p->nColumn; iCol++){
        const char *z = (const char *) sqlite3_column_text(pStmt, iCol+1);
        rc = fts3PendingTermsAdd(p, iLangid, z, iCol, &aSz[iCol]);
        aSz[p->nColumn] += sqlite3_column_bytes(pStmt, iCol+1);
      }
      if( p->bHasDocsize ){
        fts3InsertDocsize(&rc, p, aSz);

** SQLite value pRowid contains the rowid of a row that may or may not be
** present in the FTS3 table. If it is, delete it and adjust the contents
** of subsiduary data structures accordingly.
*/
static int fts3DeleteByRowid(
  Fts3Table *p, 
  sqlite3_value *pRowid, 
  int *pnChng,                    /* IN/OUT: Decrement if row is deleted */
  u32 *aSzDel
){
  int rc = SQLITE_OK;             /* Return code */
  int bFound = 0;                 /* True if *pRowid really is in the table */

  fts3DeleteTerms(&rc, p, pRowid, aSzDel, &bFound);
  if( bFound && rc==SQLITE_OK ){
    int isEmpty = 0;              /* Deleting *pRowid leaves the table empty */
    rc = fts3IsEmpty(p, pRowid, &isEmpty);
    if( rc==SQLITE_OK ){
      if( isEmpty ){
        /* Deleting this row means the whole table is empty. In this case
        ** delete the contents of all three tables and throw away any
        ** data in the pendingTerms hash table.  */
        rc = fts3DeleteAll(p, 1);
        *pnChng = 0;
        memset(aSzDel, 0, sizeof(u32) * (p->nColumn+1) * 2);
      }else{

        *pnChng = *pnChng - 1;
        if( p->zContentTbl==0 ){
          fts3SqlExec(&rc, p, SQL_DELETE_CONTENT, &pRowid);



        }
        if( p->bHasDocsize ){
          fts3SqlExec(&rc, p, SQL_DELETE_DOCSIZE, &pRowid);
        }
      }
    }
  }

  return rc;
}

  if( nArg>1 && sqlite3_value_int(apVal[2 + p->nColumn + 2])<0 ){
    rc = SQLITE_CONSTRAINT;
    goto update_out;
  }

  /* Allocate space to hold the change in document sizes */
  aSzDel = sqlite3_malloc( sizeof(aSzDel[0])*(p->nColumn+1)*2 );
  if( aSzDel==0 ){
    rc = SQLITE_NOMEM;
    goto update_out;
  }
  aSzIns = &aSzDel[p->nColumn+1];
  memset(aSzDel, 0, sizeof(aSzDel[0])*(p->nColumn+1)*2);

  /* If this is an INSERT operation, or an UPDATE that modifies the rowid
  ** value, then this operation requires constraint handling.
  **
  ** If the on-conflict mode is REPLACE, this means that the existing row
  ** should be deleted from the database before inserting the new row. Or,
  ** if the on-conflict mode is other than REPLACE, then this method must

  }

  if( p->bFts4 ){
    fts3UpdateDocTotals(&rc, p, aSzIns, aSzDel, nChng);
  }

 update_out:
  sqlite3_free(aSzDel);
  sqlite3Fts3SegmentsClose(p);
  return rc;
}

/* 
** Flush any data in the pending-terms hash table to disk. If successful,
** merge all segments in the database (including the new segment, if 

  $(TOP)/src/test_osinst.c \
  $(TOP)/src/test_pcache.c \
  $(TOP)/src/test_quota.c \
  $(TOP)/src/test_rtree.c \
  $(TOP)/src/test_schema.c \
  $(TOP)/src/test_server.c \
  $(TOP)/src/test_stat.c \
  $(TOP)/src/test_sqllog.c \
  $(TOP)/src/test_superlock.c \
  $(TOP)/src/test_syscall.c \
  $(TOP)/src/test_tclvar.c \
  $(TOP)/src/test_thread.c \
  $(TOP)/src/test_vfs.c \
  $(TOP)/src/test_wholenumber.c \
  $(TOP)/src/test_wsd.c

   0,                         /* isMallocInit */
   0,                         /* isPCacheInit */
   0,                         /* pInitMutex */
   0,                         /* nRefInitMutex */
   0,                         /* xLog */
   0,                         /* pLogArg */
   0,                         /* bLocaltimeFault */
#ifdef SQLITE_ENABLE_SQLLOG
   0,                         /* xSqllog */
   0                          /* pSqllogArg */
#endif
};


/*
** Hash table for global functions - functions common to all
** database connections.  After initialization, this table is
** read-only.

  /* If SQLite is already completely initialized, then this call
  ** to sqlite3_initialize() should be a no-op.  But the initialization
  ** must be complete.  So isInit must not be set until the very end
  ** of this routine.
  */
  if( sqlite3GlobalConfig.isInit ) return SQLITE_OK;

#ifdef SQLITE_ENABLE_SQLLOG
  {
    extern void sqlite3_init_sqllog(void);
    sqlite3_init_sqllog();
  }
#endif

  /* Make sure the mutex subsystem is initialized.  If unable to 
  ** initialize the mutex subsystem, return early with the error.
  ** If the system is so sick that we are unable to allocate a mutex,
  ** there is not much SQLite is going to be able to do.
  **
  ** The mutex subsystem must take care of serializing its own

      break;
    }

    case SQLITE_CONFIG_COVERING_INDEX_SCAN: {
      sqlite3GlobalConfig.bUseCis = va_arg(ap, int);
      break;
    }

#ifdef SQLITE_ENABLE_SQLLOG
    case SQLITE_CONFIG_SQLLOG: {
      typedef void(*SQLLOGFUNC_t)(void*, sqlite3*, const char*, int);
      sqlite3GlobalConfig.xSqllog = va_arg(ap, SQLLOGFUNC_t);
      sqlite3GlobalConfig.pSqllogArg = va_arg(ap, void *);
      break;
    }
#endif

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

  */
  if( !forceZombie && connectionIsBusy(db) ){
    sqlite3Error(db, SQLITE_BUSY, "unable to close due to unfinalized "
       "statements or unfinished backups");
    sqlite3_mutex_leave(db->mutex);
    return SQLITE_BUSY;
  }

#ifdef SQLITE_ENABLE_SQLLOG
  if( sqlite3GlobalConfig.xSqllog ){
    /* Closing the handle. Fourth parameter is passed the value 2. */
    sqlite3GlobalConfig.xSqllog(sqlite3GlobalConfig.pSqllogArg, db, 0, 2);
  }
#endif

  /* Convert the connection into a zombie and then close it.
  */
  db->magic = SQLITE_MAGIC_ZOMBIE;
  sqlite3LeaveMutexAndCloseZombie(db);
  return SQLITE_OK;
}

  if( rc==SQLITE_NOMEM ){
    sqlite3_close(db);
    db = 0;
  }else if( rc!=SQLITE_OK ){
    db->magic = SQLITE_MAGIC_SICK;
  }
  *ppDb = db;
#ifdef SQLITE_ENABLE_SQLLOG
  if( sqlite3GlobalConfig.xSqllog ){
    /* Opening a db handle. Fourth parameter is passed 0. */
    void *pArg = sqlite3GlobalConfig.pSqllogArg;
    sqlite3GlobalConfig.xSqllog(pArg, db, zFilename, 0);
  }
#endif
  return sqlite3ApiExit(0, rc);
}

/*
** Open a new database handle.
*/
int sqlite3_open(

**   *  Locking primitives for the proxy uber-locking-method. (MacOSX only)
**   *  Definitions of sqlite3_vfs objects for all locking methods
**      plus implementations of sqlite3_os_init() and sqlite3_os_end().
*/
#include "sqliteInt.h"
#if SQLITE_OS_UNIX              /* This file is used on unix only */

/* Use posix_fallocate() if it is available
*/
#if !defined(HAVE_POSIX_FALLOCATE) \
      && (_XOPEN_SOURCE >= 600 || _POSIX_C_SOURCE >= 200112L)
# define HAVE_POSIX_FALLOCATE 1
#endif

/*
** There are various methods for file locking used for concurrency
** control:
**
**   1. POSIX locking (the default),
**   2. No locking,
**   3. Dot-file locking,

        /* The requested memory region does not exist. If bExtend is set to
        ** false, exit early. *pp will be set to NULL and SQLITE_OK returned.
        **
        ** Alternatively, if bExtend is true, use ftruncate() to allocate
        ** the requested memory region.
        */
        if( !bExtend ) goto shmpage_out;
#if defined(HAVE_POSIX_FALLOCATE) && HAVE_POSIX_FALLOCATE
        if( osFallocate(pShmNode->h, sStat.st_size, nByte)!=0 ){
          rc = unixLogError(SQLITE_IOERR_SHMSIZE, "fallocate",
                            pShmNode->zFilename);
          goto shmpage_out;
        }
#else
        if( robust_ftruncate(pShmNode->h, nByte) ){
          rc = unixLogError(SQLITE_IOERR_SHMSIZE, "ftruncate",
                            pShmNode->zFilename);
          goto shmpage_out;
        }
#endif
      }
    }

    /* Map the requested memory region into this processes address space. */
    apNew = (char **)sqlite3_realloc(
        pShmNode->apRegion, (iRegion+1)*sizeof(char *)
    );

#if SQLITE_OS_WINRT
      WIN32_FILE_ATTRIBUTE_DATA sAttrData;
      memset(&sAttrData, 0, sizeof(sAttrData));
      if ( osGetFileAttributesExW(zConverted, GetFileExInfoStandard,
                                  &sAttrData) ){
        attr = sAttrData.dwFileAttributes;
      }else{
        lastErrno = osGetLastError();
        if( lastErrno==ERROR_FILE_NOT_FOUND || lastErrno==ERROR_PATH_NOT_FOUND ){
          rc = SQLITE_IOERR_DELETE_NOENT; /* Already gone? */
        }else{
          rc = SQLITE_ERROR;
        }
        break;
      }
#else
      attr = osGetFileAttributesW(zConverted);
#endif
      if ( attr==INVALID_FILE_ATTRIBUTES ){
        lastErrno = osGetLastError();
        if( lastErrno==ERROR_FILE_NOT_FOUND || lastErrno==ERROR_PATH_NOT_FOUND ){
          rc = SQLITE_IOERR_DELETE_NOENT; /* Already gone? */
        }else{
          rc = SQLITE_ERROR;
        }
        break;
      }
      if ( attr&FILE_ATTRIBUTE_DIRECTORY ){
        rc = SQLITE_ERROR; /* Files only. */
        break;
      }
      if ( osDeleteFileW(zConverted) ){

    } while(1);
  }
#ifdef SQLITE_WIN32_HAS_ANSI
  else{
    do {
      attr = osGetFileAttributesA(zConverted);
      if ( attr==INVALID_FILE_ATTRIBUTES ){
        lastErrno = osGetLastError();
        if( lastErrno==ERROR_FILE_NOT_FOUND || lastErrno==ERROR_PATH_NOT_FOUND ){
          rc = SQLITE_IOERR_DELETE_NOENT; /* Already gone? */
        }else{
          rc = SQLITE_ERROR;
        }
        break;
      }
      if ( attr&FILE_ATTRIBUTE_DIRECTORY ){
        rc = SQLITE_ERROR; /* Files only. */
        break;
      }
      if ( osDeleteFileA(zConverted) ){
        rc = SQLITE_OK; /* Deleted OK. */
        break;
      }
      if ( !retryIoerr(&cnt, &lastErrno) ){
        rc = SQLITE_ERROR; /* No more retries. */
        break;
      }
    } while(1);
  }
#endif
  if( rc && rc!=SQLITE_IOERR_DELETE_NOENT ){
    rc = winLogError(SQLITE_IOERR_DELETE, lastErrno,
             "winDelete", zFilename);
  }else{
    logIoerr(cnt);
  }
  sqlite3_free(zConverted);
  OSTRACE(("DELETE \"%s\" %s\n", zFilename, (rc ? "failed" : "ok" )));

** without change even with newer versions of SQLite.
**
** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE
** <dd> These options are obsolete and should not be used by new code.
** They are retained for backwards compatibility but are now no-ops.
** </dl>
**
** [[SQLITE_CONFIG_SQLLOG]]
** <dt>SQLITE_CONFIG_SQLLOG
** <dd>This option is only available if sqlite is compiled with the
** SQLITE_ENABLE_SQLLOG pre-processor macro defined. The first argument should
** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int).
** The second should be of type (void*). The callback is invoked by the library
** in three separate circumstances, identified by the value passed as the
** fourth parameter. If the fourth parameter is 0, then the database connection
** passed as the second argument has just been opened. The third argument
** points to a buffer containing the name of the main database file. If the
** fourth parameter is 1, then the SQL statement that the third parameter
** points to has just been executed. Or, if the fourth parameter is 2, then
** the connection being passed as the second parameter is being closed. The
** third parameter is passed NULL In this case.
** </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_SCRATCH       6  /* void*, int sz, int N */

#define SQLITE_CONFIG_PCACHE       14  /* no-op */
#define SQLITE_CONFIG_GETPCACHE    15  /* no-op */
#define SQLITE_CONFIG_LOG          16  /* xFunc, void* */
#define SQLITE_CONFIG_URI          17  /* int */
#define SQLITE_CONFIG_PCACHE2      18  /* sqlite3_pcache_methods2* */
#define SQLITE_CONFIG_GETPCACHE2   19  /* sqlite3_pcache_methods2* */
#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20  /* int */
#define SQLITE_CONFIG_SQLLOG       21  /* xSqllog, void* */

/*
** 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 isMallocInit;                 /* True after malloc is initialized */
  int isPCacheInit;                 /* True after malloc is initialized */
  sqlite3_mutex *pInitMutex;        /* Mutex used by sqlite3_initialize() */
  int nRefInitMutex;                /* Number of users of pInitMutex */
  void (*xLog)(void*,int,const char*); /* Function for logging */
  void *pLogArg;                       /* First argument to xLog() */
  int bLocaltimeFault;              /* True to fail localtime() calls */
#ifdef SQLITE_ENABLE_SQLLOG
  void(*xSqllog)(void*,sqlite3*,const char*, int);
  void *pSqllogArg;
#endif
};

/*
** Context pointer passed down through the tree-walk.
*/
struct Walker {
  int (*xExprCallback)(Walker*, Expr*);     /* Callback for expressions */

/*
** 2012 November 26
**
** 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.
**
*************************************************************************
**
** OVERVIEW
**
**   This file contains experimental code used to record data from live
**   SQLite applications that may be useful for offline analysis. Specifically:
**
**     1) The initial contents of all database files opened by the 
**        application, and
**
**     2) All SQL statements executed by the application.
**
** USAGE
**
**   To use this module, SQLite must be compiled with the SQLITE_ENABLE_SQLLOG
**   pre-processor symbol defined and this file linked into the application
**   somehow.
**
**   At runtime, logging is enabled by setting environment variable
**   SQLITE_SQLLOG_DIR to the name of a directory in which to store logged 
**   data. The directory must already exist.
**
**   Usually, if the application opens the same database file more than once
**   (either by attaching it or by using more than one database handle), only
**   a single copy is made. This behaviour may be overridden (so that a 
**   separate copy is taken each time the database file is opened or attached)
**   by setting the environment variable SQLITE_SQLLOG_REUSE_FILES to 0.
**
** OUTPUT:
**
**   The SQLITE_SQLLOG_DIR is populated with three types of files:
**
**      sqllog_N.db   - Copies of database files. N may be any integer.
**
**      sqllog_N.sql  - A list of SQL statements executed by a single
**                      connection. N may be any integer.
**
**      sqllog.idx    - An index mapping from integer N to a database
**                      file name - indicating the full path of the
**                      database from which sqllog_N.db was copied.
**
** ERROR HANDLING:
**
**   This module attempts to make a best effort to continue logging if an
**   IO or other error is encountered. For example, if a log file cannot 
**   be opened logs are not collected for that connection, but other
**   logging proceeds as expected. Errors are logged by calling sqlite3_log().
*/

#include "sqlite3.h"
#include "stdio.h"
#include "stdlib.h"
#include "string.h"
#include "assert.h"

#include "sys/types.h"
#include "unistd.h"
static int getProcessId(void){
#if SQLITE_OS_WIN
  return (int)_getpid();
#else
  return (int)getpid();
#endif
}


#define ENVIRONMENT_VARIABLE1_NAME "SQLITE_SQLLOG_DIR"
#define ENVIRONMENT_VARIABLE2_NAME "SQLITE_SQLLOG_REUSE_FILES"

/* Assume that all database and database file names are shorted than this. */
#define SQLLOG_NAMESZ 512

/* Maximum number of simultaneous database connections the process may
** open (if any more are opened an error is logged using sqlite3_log()
** and processing is halted).
*/
#define MAX_CONNECTIONS 256

struct SLConn {
  int isErr;                      /* True if an error has occurred */
  sqlite3 *db;                    /* Connection handle */
  int iLog;                       /* First integer value used in file names */
  FILE *fd;                       /* File descriptor for log file */
};

struct SLGlobal {
  /* Protected by MUTEX_STATIC_MASTER */
  sqlite3_mutex *mutex;           /* Recursive mutex */
  int nConn;                      /* Size of aConn[] array */

  /* Protected by SLGlobal.mutex */
  int bReuse;                     /* True to avoid extra copies of db files */
  char zPrefix[SQLLOG_NAMESZ];    /* Prefix for all created files */
  char zIdx[SQLLOG_NAMESZ];       /* Full path to *.idx file */
  int iNextLog;                   /* Used to allocate file names */
  int iNextDb;                    /* Used to allocate database file names */
  int bRec;                       /* True if testSqllog() is called rec. */
  int iClock;                     /* Clock value */
  struct SLConn aConn[MAX_CONNECTIONS];
} sqllogglobal;

/*
** Return true if c is an ASCII whitespace character.
*/
static int sqllog_isspace(char c){
  return (c==' ' || c=='\t' || c=='\n' || c=='\v' || c=='\f' || c=='\r');
}

/*
** The first argument points to a nul-terminated string containing an SQL
** command. Before returning, this function sets *pz to point to the start
** of the first token in this command, and *pn to the number of bytes in 
** the token. This is used to check if the SQL command is an "ATTACH" or 
** not.
*/
static void sqllogTokenize(const char *z, const char **pz, int *pn){
  const char *p = z;
  int n;

  /* Skip past any whitespace */
  while( sqllog_isspace(*p) ){
    p++;
  }

  /* Figure out how long the first token is */
  *pz = p;
  n = 0;
  while( (p[n]>='a' && p[n]<='z') || (p[n]>='A' && p[n]<='Z') ) n++;
  *pn = n;
}

/*
** Check if the logs directory already contains a copy of database file 
** zFile. If so, return a pointer to the full path of the copy. Otherwise,
** return NULL.
**
** If a non-NULL value is returned, then the caller must arrange to 
** eventually free it using sqlite3_free().
*/
static char *sqllogFindFile(const char *zFile){
  char *zRet = 0;
  FILE *fd = 0;

  /* Open the index file for reading */
  fd = fopen(sqllogglobal.zIdx, "r");
  if( fd==0 ){
    sqlite3_log(SQLITE_IOERR, "sqllogFindFile(): error in fopen()");
    return 0;
  }

  /* Loop through each entry in the index file. If zFile is not NULL and the
  ** entry is a match, then set zRet to point to the filename of the existing
  ** copy and break out of the loop.  */
  while( feof(fd)==0 ){
    char zLine[SQLLOG_NAMESZ*2+5];
    if( fgets(zLine, sizeof(zLine), fd) ){
      int n;
      char *z;

      zLine[sizeof(zLine)-1] = '\0';
      z = zLine;
      while( *z>='0' && *z<='9' ) z++;
      while( *z==' ' ) z++;

      n = strlen(z);
      while( n>0 && sqllog_isspace(z[n-1]) ) n--;

      if( n==strlen(zFile) && 0==memcmp(zFile, z, n) ){
        char zBuf[16];
        memset(zBuf, 0, sizeof(zBuf));
        z = zLine;
        while( *z>='0' && *z<='9' ){
          zBuf[z-zLine] = *z;
          z++;
        }
        zRet = sqlite3_mprintf("%s_%s.db", sqllogglobal.zPrefix, zBuf);
        break;
      }
    }
  }

  if( ferror(fd) ){
    sqlite3_log(SQLITE_IOERR, "sqllogFindFile(): error reading index file");
  }

  fclose(fd);
  return zRet;
}

static int sqllogFindAttached(
  struct SLConn *p,               /* Database connection */
  const char *zSearch,            /* Name to search for (or NULL) */
  char *zName,                    /* OUT: Name of attached database */
  char *zFile                     /* OUT: Name of attached file */
){
  sqlite3_stmt *pStmt;
  int rc;

  /* The "PRAGMA database_list" command returns a list of databases in the
  ** order that they were attached. So a newly attached database is 
  ** described by the last row returned.  */
  assert( sqllogglobal.bRec==0 );
  sqllogglobal.bRec = 1;
  rc = sqlite3_prepare_v2(p->db, "PRAGMA database_list", -1, &pStmt, 0);
  if( rc==SQLITE_OK ){
    while( SQLITE_ROW==sqlite3_step(pStmt) ){
      const char *zVal1; int nVal1;
      const char *zVal2; int nVal2;

      zVal1 = (const char*)sqlite3_column_text(pStmt, 1);
      nVal1 = sqlite3_column_bytes(pStmt, 1);
      memcpy(zName, zVal1, nVal1+1);

      zVal2 = (const char*)sqlite3_column_text(pStmt, 2);
      nVal2 = sqlite3_column_bytes(pStmt, 2);
      memcpy(zFile, zVal2, nVal2+1);

      if( zSearch && strlen(zSearch)==nVal1 
       && 0==sqlite3_strnicmp(zSearch, zVal1, nVal1)
      ){
        break;
      }
    }
    rc = sqlite3_finalize(pStmt);
  }
  sqllogglobal.bRec = 0;

  if( rc!=SQLITE_OK ){
    sqlite3_log(rc, "sqllogFindAttached(): error in \"PRAGMA database_list\"");
  }
  return rc;
}


/*
** Parameter zSearch is the name of a database attached to the database 
** connection associated with the first argument. This function creates
** a backup of this database in the logs directory.
**
** The name used for the backup file is automatically generated. Call
** it zFile.
**
** If the bLog parameter is true, then a statement of the following form
** is written to the log file associated with *p:
**
**    ATTACH 'zFile' AS 'zName';
**
** Otherwise, if bLog is false, a comment is added to the log file:
**
**    -- Main database file is 'zFile'
**
** The SLGlobal.mutex mutex is always held when this function is called.
*/
static void sqllogCopydb(struct SLConn *p, const char *zSearch, int bLog){
  char zName[SQLLOG_NAMESZ];      /* Attached database name */
  char zFile[SQLLOG_NAMESZ];      /* Database file name */
  char *zFree;
  char *zInit = 0;
  int rc;

  rc = sqllogFindAttached(p, zSearch, zName, zFile);
  if( rc!=SQLITE_OK ) return;

  if( zFile[0]=='\0' ){
    zInit = sqlite3_mprintf("");
  }else{
    if( sqllogglobal.bReuse ){
      zInit = sqllogFindFile(zFile);
    }else{
      zInit = 0;
    }
    if( zInit==0 ){
      int rc;
      sqlite3 *copy = 0;
      int iDb;

      /* Generate a file-name to use for the copy of this database */
      iDb = sqllogglobal.iNextDb++;
      zInit = sqlite3_mprintf("%s_%d.db", sqllogglobal.zPrefix, iDb);

      /* Create the backup */
      assert( sqllogglobal.bRec==0 );
      sqllogglobal.bRec = 1;
      rc = sqlite3_open(zInit, &copy);
      if( rc==SQLITE_OK ){
        sqlite3_backup *pBak;
        sqlite3_exec(copy, "PRAGMA synchronous = 0", 0, 0, 0);
        pBak = sqlite3_backup_init(copy, "main", p->db, zName);
        if( pBak ){
          sqlite3_backup_step(pBak, -1);
          rc = sqlite3_backup_finish(pBak);
        }else{
          rc = sqlite3_errcode(copy);
        }
        sqlite3_close(copy);
      }
      sqllogglobal.bRec = 0;

      if( rc==SQLITE_OK ){
        /* Write an entry into the database index file */
        FILE *fd = fopen(sqllogglobal.zIdx, "a");
        if( fd ){
          fprintf(fd, "%d %s\n", iDb, zFile);
          fclose(fd);
        }
      }else{
        sqlite3_log(rc, "sqllogCopydb(): error backing up database");
      }
    }
  }

  if( bLog ){
    zFree = sqlite3_mprintf("ATTACH '%q' AS '%q'; -- clock=%d\n", 
        zInit, zName, sqllogglobal.iClock++
    );
  }else{
    zFree = sqlite3_mprintf("-- Main database is '%q'\n", zInit);
  }
  fprintf(p->fd, "%s", zFree);
  sqlite3_free(zFree);

  sqlite3_free(zInit);
}

/*
** If it is not already open, open the log file for connection *p. 
**
** The SLGlobal.mutex mutex is always held when this function is called.
*/
static void sqllogOpenlog(struct SLConn *p){
  /* If the log file has not yet been opened, open it now. */
  if( p->fd==0 ){
    char *zLog;

    /* If it is still NULL, have global.zPrefix point to a copy of 
    ** environment variable $ENVIRONMENT_VARIABLE1_NAME.  */
    if( sqllogglobal.zPrefix[0]==0 ){
      FILE *fd;
      char *zVar = getenv(ENVIRONMENT_VARIABLE1_NAME);
      if( zVar==0 || strlen(zVar)+10>=(sizeof(sqllogglobal.zPrefix)) ) return;
      sprintf(sqllogglobal.zPrefix, "%s/sqllog_%d", zVar, getProcessId());
      sprintf(sqllogglobal.zIdx, "%s.idx", sqllogglobal.zPrefix);
      if( getenv(ENVIRONMENT_VARIABLE2_NAME) ){
        sqllogglobal.bReuse = atoi(getenv(ENVIRONMENT_VARIABLE2_NAME));
      }
      fd = fopen(sqllogglobal.zIdx, "w");
      if( fd ) fclose(fd);
    }

    /* Open the log file */
    zLog = sqlite3_mprintf("%s_%d.sql", sqllogglobal.zPrefix, p->iLog);
    p->fd = fopen(zLog, "w");
    sqlite3_free(zLog);
    if( p->fd==0 ){
      sqlite3_log(SQLITE_IOERR, "sqllogOpenlog(): Failed to open log file");
    }
  }
}

/*
** This function is called if the SQLLOG callback is invoked to report
** execution of an SQL statement. Parameter p is the connection the statement
** was executed by and parameter zSql is the text of the statement itself.
*/
static void testSqllogStmt(struct SLConn *p, const char *zSql){
  const char *zFirst;             /* Pointer to first token in zSql */
  int nFirst;                     /* Size of token zFirst in bytes */

  sqllogTokenize(zSql, &zFirst, &nFirst);
  if( nFirst!=6 || 0!=sqlite3_strnicmp("ATTACH", zFirst, 6) ){
    /* Not an ATTACH statement. Write this directly to the log. */
    fprintf(p->fd, "%s; -- clock=%d\n", zSql, sqllogglobal.iClock++);
  }else{
    /* This is an ATTACH statement. Copy the database. */
    sqllogCopydb(p, 0, 1);
  }
}

/*
** The SQLITE_CONFIG_SQLLOG callback registered by sqlite3_init_sqllog().
*/
static void testSqllog(void *pCtx, sqlite3 *db, const char *zSql, int eType){
  struct SLConn *p;
  sqlite3_mutex *master = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER);

  assert( eType==0 || eType==1 || eType==2 );
  assert( (eType==2)==(zSql==0) );

  /* This is a database open command. */
  if( eType==0 ){
    sqlite3_mutex_enter(master);
    if( sqllogglobal.mutex==0 ){
      sqllogglobal.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_RECURSIVE);
    }
    p = &sqllogglobal.aConn[sqllogglobal.nConn++];
    p->fd = 0;
    p->db = db;
    p->iLog = sqllogglobal.iNextLog++;
    sqlite3_mutex_leave(master);

    /* Open the log and take a copy of the main database file */
    sqlite3_mutex_enter(sqllogglobal.mutex);
    if( sqllogglobal.bRec==0 ){
      sqllogOpenlog(p);
      if( p->fd ) sqllogCopydb(p, "main", 0);
    }
    sqlite3_mutex_leave(sqllogglobal.mutex);
  }

  else{

    int i;
    for(i=0; i<sqllogglobal.nConn; i++){
      p = &sqllogglobal.aConn[i];
      if( p->db==db ) break;
    }
    if( i==sqllogglobal.nConn ) return;

    /* A database handle close command */
    if( eType==2 ){
      sqlite3_mutex_enter(master);
      if( p->fd ) fclose(p->fd);
      p->db = 0;
      p->fd = 0;

      sqllogglobal.nConn--;
      if( sqllogglobal.nConn==0 ){
        sqlite3_mutex_free(sqllogglobal.mutex);
        sqllogglobal.mutex = 0;
      }else{
        int nShift = &sqllogglobal.aConn[sqllogglobal.nConn] - p;
        if( nShift>0 ){
          memmove(p, &p[1], nShift*sizeof(struct SLConn));
        }
      }
      sqlite3_mutex_leave(master);

    /* An ordinary SQL command. */
    }else if( p->fd ){
      sqlite3_mutex_enter(sqllogglobal.mutex);
      if( sqllogglobal.bRec==0 ){
        testSqllogStmt(p, zSql);
      }
      sqlite3_mutex_leave(sqllogglobal.mutex);
    }
  }
}

/*
** This function is called either before sqlite3_initialized() or by it.
** It checks if the SQLITE_SQLLOG_DIR variable is defined, and if so 
** registers an SQLITE_CONFIG_SQLLOG callback to record the applications
** database activity.
*/
void sqlite3_init_sqllog(void){
  if( getenv(ENVIRONMENT_VARIABLE1_NAME) ){
    if( SQLITE_OK==sqlite3_config(SQLITE_CONFIG_SQLLOG, testSqllog, 0) ){
      memset(&sqllogglobal, 0, sizeof(sqllogglobal));
      sqllogglobal.bReuse = 1;
    }
  }
}

/*
** Remember the SQL string for a prepared statement.
*/
void sqlite3VdbeSetSql(Vdbe *p, const char *z, int n, int isPrepareV2){
  assert( isPrepareV2==1 || isPrepareV2==0 );
  if( p==0 ) return;
#if defined(SQLITE_OMIT_TRACE) && !defined(SQLITE_ENABLE_SQLLOG)
  if( !isPrepareV2 ) return;
#endif
  assert( p->zSql==0 );
  p->zSql = sqlite3DbStrNDup(p->db, z, n);
  p->isPrepareV2 = (u8)isPrepareV2;
}

    db->errCode = rc;
  }else{
    sqlite3Error(db, rc, 0);
  }
  return rc;
}

#ifdef SQLITE_ENABLE_SQLLOG
/*
** If an SQLITE_CONFIG_SQLLOG hook is registered and the VM has been run, 
** invoke it.
*/
static void vdbeInvokeSqllog(Vdbe *v){
  if( sqlite3GlobalConfig.xSqllog && v->rc==SQLITE_OK && v->zSql && v->pc>=0 ){
    char *zExpanded = sqlite3VdbeExpandSql(v, v->zSql);
    assert( v->db->init.busy==0 );
    if( zExpanded ){
      sqlite3GlobalConfig.xSqllog(
          sqlite3GlobalConfig.pSqllogArg, v->db, zExpanded, 1
      );
      sqlite3DbFree(v->db, zExpanded);
    }
  }
}
#else
# define vdbeInvokeSqllog(x)
#endif

/*
** Clean up a VDBE after execution but do not delete the VDBE just yet.
** Write any error messages into *pzErrMsg.  Return the result code.
**
** After this routine is run, the VDBE should be ready to be executed
** again.
**

  /* If the VDBE has be run even partially, then transfer the error code
  ** and error message from the VDBE into the main database structure.  But
  ** if the VDBE has just been set to run but has not actually executed any
  ** instructions yet, leave the main database error information unchanged.
  */
  if( p->pc>=0 ){
    vdbeInvokeSqllog(p);
    sqlite3VdbeTransferError(p);
    sqlite3DbFree(db, p->zErrMsg);
    p->zErrMsg = 0;
    if( p->runOnlyOnce ) p->expired = 1;
  }else if( p->rc && p->expired ){
    /* The expired flag was set on the VDBE before the first call
    ** to sqlite3_step(). For consistency (since sqlite3_step() was

    INSERT INTO t1(docid, x) VALUES(1, 'a b c');
    REPLACE INTO t1(docid, x) VALUES('zero', 'd e f');
} {1 {datatype mismatch}}
do_execsql_test 2.2.2 { COMMIT }
do_execsql_test 2.2.3 { SELECT * FROM t1 } {{a b c} {a b c}}
fts3_integrity 2.2.4 db t1

do_execsql_test 3.1 {
  CREATE VIRTUAL TABLE t3 USING fts4;
  REPLACE INTO t3(docid, content) VALUES (1, 'one two');
  SELECT quote(matchinfo(t3, 'na')) FROM t3 WHERE t3 MATCH 'one'
} {X'0100000002000000'}

do_execsql_test 3.2 {
  REPLACE INTO t3(docid, content) VALUES (2, 'one two three four');
  SELECT quote(matchinfo(t3, 'na')) FROM t3 WHERE t3 MATCH 'four'
} {X'0200000003000000'}

do_execsql_test 3.3 {
  REPLACE INTO t3(docid, content) VALUES (1, 'one two three four five six');
  SELECT quote(matchinfo(t3, 'na')) FROM t3 WHERE t3 MATCH 'six'
} {X'0200000005000000'}

do_execsql_test 3.4 {
  UPDATE OR REPLACE t3 SET docid = 2 WHERE docid=1;
  SELECT quote(matchinfo(t3, 'na')) FROM t3 WHERE t3 MATCH 'six'
} {X'0100000006000000'}

do_execsql_test 3.5 {
  UPDATE OR REPLACE t3 SET docid = 3 WHERE docid=2;
  SELECT quote(matchinfo(t3, 'na')) FROM t3 WHERE t3 MATCH 'six'
} {X'0100000006000000'}

do_execsql_test 3.6 {
  REPLACE INTO t3(docid, content) VALUES (3, 'one two');
  SELECT quote(matchinfo(t3, 'na')) FROM t3 WHERE t3 MATCH 'one'
} {X'0100000002000000'}

do_execsql_test 3.7 {
  REPLACE INTO t3(docid, content) VALUES (NULL, 'one two three four');
  REPLACE INTO t3(docid, content) VALUES (NULL, 'one two three four five six');
  SELECT docid FROM t3;
} {3 4 5}

do_execsql_test 3.8 {
  UPDATE OR REPLACE t3 SET docid = 5, content='three four' WHERE docid = 4;
  SELECT quote(matchinfo(t3, 'na')) FROM t3 WHERE t3 MATCH 'one'
} {X'0200000002000000'}

finish_test

  COMMIT;
} {}

# Check file sizes are as expected. The real requirement here is that 
# the *shm file is now more than one chunk (>32KiB).
do_test 1.3 { file size test.db     } {1024}
do_test 1.4 { file size test.db-wal } {15421352}
do_test 1.5 { expr {[file size test.db-shm]>32768} } {1}

do_execsql_test 1.6 { PRAGMA wal_checkpoint } {0 14715 14715}

# At this point connection [db2] has mapped the first 32KB of the *shm file
# only. Because the entire WAL file has been checkpointed, it is not 
# necessary to map any more of the *-shm file to read or write the database
# (since all data will be read directly from the db file). 

      INSERT INTO t VALUES('hello');
    ROLLBACK;
  } db2
} {}
db2 close

finish_test