SQLite

      newLimit = aHardLimit[limitId];  /* IMP: R-51463-25634 */
    }
    db->aLimit[limitId] = newLimit;
  }
  return oldLimit;                     /* IMP: R-53341-35419 */
}
#if defined(SQLITE_ENABLE_AUTO_PROFILE)
/* stderr logging */
void _sqlite_auto_profile(void *aux, const char *sql, u64 ns);
void _sqlite_auto_trace(void *aux, const char *sql);
void _sqlite_auto_profile(void *aux, const char *sql, u64 ns) {
#pragma unused(aux)
	fprintf(stderr, "Query: %s\n Execution Time: %llu ms\n", sql, ns / 1000000);
}
void _sqlite_auto_trace(void *aux, const char *sql) {
	fprintf(stderr, "TraceSQL(%p): %s\n", aux, sql);
}

/* syslog logging */
#include <asl.h>
static aslclient autolog_client = NULL;
static void _close_asl_log() {
  if( NULL!=autolog_client ){
    asl_close(autolog_client);
    autolog_client = NULL;
  }
}
static void _open_asl_log() {
  if( NULL==autolog_client ){
    autolog_client = asl_open("SQLite", NULL, 0);
    atexit(_close_asl_log);
  }
}

void _sqlite_auto_profile_syslog(void *aux, const char *sql, u64 ns);
void _sqlite_auto_trace_syslog(void *aux, const char *sql);
void _sqlite_auto_profile_syslog(void *aux, const char *sql, u64 ns) {
#pragma unused(aux)
	asl_log(autolog_client, NULL, ASL_LEVEL_NOTICE, "Query: %s\n Execution Time: %llu ms\n", sql, ns / 1000000);
}
void _sqlite_auto_trace_syslog(void *aux, const char *sql) {
	asl_log(autolog_client, NULL, ASL_LEVEL_NOTICE, "TraceSQL(%p): %s\n", aux, sql);
}
#endif

/*
** This function is used to parse both URIs and non-URI filenames passed by the
** user to API functions sqlite3_open() or sqlite3_open_v2(), and for database
** URIs specified as part of ATTACH statements.
**

    zFile = 0;
  }
  *pFlags = flags;
  *pzFile = zFile;
  return rc;
}

#if defined(SQLITE_ENABLE_AUTO_PROFILE)
#define SQLITE_AUTOLOGGING_STDERR 1
#define SQLITE_AUTOLOGGING_SYSLOG 2
static void enableAutoLogging(
  sqlite3 *db
){
  char *envprofile = getenv("SQLITE_AUTO_PROFILE");
  
  if( envprofile!=NULL ){
    int where = 0;
    if( !strncasecmp("1", envprofile, 1) ){
      if( isatty(STDERR_FILENO) ){
        where = SQLITE_AUTOLOGGING_STDERR;
      }else{
        where = SQLITE_AUTOLOGGING_SYSLOG;
      }
    } else if( !strncasecmp("stderr", envprofile, 6) ){
      where = SQLITE_AUTOLOGGING_STDERR;
    } else if( !strncasecmp("syslog", envprofile, 6) ){
      where = SQLITE_AUTOLOGGING_SYSLOG;
    }
    if( where==SQLITE_AUTOLOGGING_STDERR ){
      sqlite3_profile(db, _sqlite_auto_profile, db);
    }else if( where==SQLITE_AUTOLOGGING_SYSLOG ){
      _open_asl_log();
      sqlite3_profile(db, _sqlite_auto_profile_syslog, db);
    }
  }
  char *envtrace = getenv("SQLITE_AUTO_TRACE");
  if( envtrace!=NULL ){
    int where = 0;
    if( !strncasecmp("1", envtrace, 1) ){
      if( isatty(STDERR_FILENO) ){
        where = SQLITE_AUTOLOGGING_STDERR;
      }else{
        where = SQLITE_AUTOLOGGING_SYSLOG;
      }
    } else if( !strncasecmp("stderr", envtrace, 6) ){
      where = SQLITE_AUTOLOGGING_STDERR;
    } else if( !strncasecmp("syslog", envtrace, 6) ){
      where = SQLITE_AUTOLOGGING_SYSLOG;
    }
    if( where==SQLITE_AUTOLOGGING_STDERR ){
      sqlite3_trace(db, _sqlite_auto_trace, db);
    }else if( where==SQLITE_AUTOLOGGING_SYSLOG ){
      _open_asl_log();
      sqlite3_trace(db, _sqlite_auto_trace_syslog, db);
    }
  }
}
#endif

/*
** This routine does the work of opening a database on behalf of
** sqlite3_open() and sqlite3_open16(). The database filename "zFilename"  
** is UTF-8 encoded.
*/
static int openDatabase(

  assert( db!=0 || rc==SQLITE_NOMEM );
  if( rc==SQLITE_NOMEM ){
    sqlite3_close(db);
    db = 0;
  }else if( rc!=SQLITE_OK ){
    db->magic = SQLITE_MAGIC_SICK;
  }
#if defined(__APPLE__) && ENABLE_FORCE_WAL
  if( db && !rc ){
    if ((0 == access("/var/db/enableForceWAL", R_OK))) {
#ifdef SQLITE_DEBUG
      fprintf(stderr, "SQLite WAL journal_mode ENABLED by default.\n");
#endif
      

      sqlite3_exec(db, "pragma journal_mode=wal", NULL, NULL, NULL);
#ifdef SQLITE_DEBUG
//    } else {
//      fprintf(stderr, "SQLite WAL journal_mode NOT ENABLED by default.\n");
#endif
    }


  }
#endif
#if defined(SQLITE_ENABLE_AUTO_PROFILE)
  if( db && !rc ){
    enableAutoLogging(db);
  }
#endif
  *ppDb = db;
#ifdef SQLITE_ENABLE_SQLRR
  SRRecOpen(db, zFilename, flags);
#endif
  return sqlite3ApiExit(0, rc);

  if( sqlite3_open_v2(path, &db, SQLITE_OPEN_READONLY, NULL) == SQLITE_OK ){
    LockstatePID lockstate = {pid, -1};
    sqlite3_file_control(db, NULL, SQLITE_FCNTL_LOCKSTATE_PID, &lockstate);
    sqlite3_close(db);
    int state = lockstate.state;
    return state;
  }
  if( NULL!=db ){ 
    sqlite3_close(db); /* need to close even if open returns an error */
  }
  return SQLITE_LOCKSTATE_ERROR;
}

#endif /* SQLITE_ENABLE_APPLE_SPI */

        }
        lock.l_type = F_RDLCK;
        lock.l_whence = SEEK_SET;
        lock.l_start = SHARED_FIRST;
        lock.l_len = divSize;
        if( unixFileLock(pFile, &lock, 10)==(-1) ){
          tErrno = errno;
#if OSLOCKING_CHECK_BUSY_IOERR
          rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_RDLOCK);
#else
          rc = SQLITE_IOERR_UNLOCK;
#endif
          if( IS_LOCK_ERROR(rc) ){
            pFile->lastErrno = tErrno;
          }
          goto end_unlock;
        }
        lock.l_type = F_UNLCK;
        lock.l_whence = SEEK_SET;

  return SQLITE_OK;
}

/*
** Close the file.
*/
static int nolockClose(sqlite3_file *id) {
  int rc = SQLITE_OK;
  unixFile *pFile = (unixFile *)id;
  unixEnterMutex();
  
  /* unixFile.pInode is always valid here. Otherwise, a different close
   ** routine (e.g. nolockClose()) would be called instead.
   */
  assert( pFile->pInode->nLock>0 || pFile->pInode->bProcessLock==0 );
  if( ALWAYS(pFile->pInode) && pFile->pInode->nLock ){
    /* If there are outstanding locks, do not actually close the file just
     ** yet because that would clear those locks.  Instead, add the file
     ** descriptor to pInode->pUnused list.  It will be automatically closed 
     ** when the last lock is cleared.
     */
    setPendingFd(pFile);
  }
  releaseInodeInfo(pFile);
  rc = closeUnixFile(id);
  unixLeaveMutex();
  return rc;
}

/******************* End of the no-op lock implementation *********************
******************************************************************************/

/******************************************************************************
************************* Begin dot-file Locking ******************************

      }
#endif
    }
  }

  return SQLITE_OK;
}


#if (SQLITE_ENABLE_APPLE_SPI>0) && defined(__APPLE__)
#include "sqlite3_private.h"
#include <copyfile.h>
static int getDbPathForUnixFile(unixFile *pFile, char *dbPath);
#endif
static int isProxyLockingMode(unixFile *);

#if (SQLITE_ENABLE_APPLE_SPI>0) && defined(__APPLE__)
static int unixTruncateDatabase(unixFile *, int);









































static int unixInvalidateSupportFiles(unixFile *, int);

























































static int unixReplaceDatabase(unixFile *pFile, sqlite3 *srcdb) {
  sqlite3_file *id = (sqlite3_file *)pFile;
  Btree *pSrcBtree = NULL;
  sqlite3_file *src_file = NULL;
  unixFile *pSrcFile = NULL;
  char srcWalPath[MAXPATHLEN+5];

    fprintf(stderr, "%s lock held by %d\n", zType, (int)lk.l_pid);
#endif
    return 1;
  } 
  return 0;
}





static int unixLockstatePid(unixFile *, pid_t, int *);
















































































#endif /* (SQLITE_ENABLE_APPLE_SPI>0) && defined(__APPLE__) */


/*
** If *pArg is inititially negative then this is a query.  Set *pArg to
** 1 or 0 depending on whether or not bit mask of pFile->ctrlFlags is set.

static int unixFileControl(sqlite3_file *id, int op, void *pArg){
  unixFile *pFile = (unixFile*)id;
  switch( op ){
    case SQLITE_FCNTL_LOCKSTATE: {
      *(int*)pArg = pFile->eFileLock;
      return SQLITE_OK;
    }
    case SQLITE_FCNTL_LAST_ERRNO: {
      *(int*)pArg = pFile->lastErrno;
      return SQLITE_OK;
    }
    case SQLITE_FCNTL_CHUNK_SIZE: {
      pFile->szChunk = *(int *)pArg;
      return SQLITE_OK;
    }

    */
    case SQLITE_FCNTL_DB_UNCHANGED: {
      ((unixFile*)id)->dbUpdate = 0;
      return SQLITE_OK;
    }
#endif
#if SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__)
    case SQLITE_FCNTL_SET_LOCKPROXYFILE:
    case SQLITE_FCNTL_GET_LOCKPROXYFILE: {
      return proxyFileControl(id,op,pArg);
    }
#endif /* SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__) */
#if (SQLITE_ENABLE_APPLE_SPI>0) && defined(__APPLE__)
    case SQLITE_FCNTL_TRUNCATE_DATABASE: {
      return unixTruncateDatabase(pFile, (pArg ? (*(int *)pArg) : 0));
    }

  /* If pShmNode->nRef has reached 0, then close the underlying
  ** shared-memory file, too */
  unixEnterMutex();
  assert( pShmNode->nRef>0 );
  pShmNode->nRef--;
  if( pShmNode->nRef==0 ){
    if( deleteFlag && pShmNode->h>=0 ) {
      if (deleteFlag == 1) { 
        unlink(pShmNode->zFilename);
      } else if (deleteFlag == 2) {
        //ftruncate(pShmNode->h, 32 * 1024);
      }
    }
    
    unixShmPurge(pDbFd);
  }
  unixLeaveMutex();

  return SQLITE_OK;
}


#else
# define unixShmMap     0
# define unixShmLock    0
# define unixShmBarrier 0
# define unixShmUnmap   0
#endif /* #ifndef SQLITE_OMIT_WAL */

#if (SQLITE_ENABLE_APPLE_SPI>0) && defined(__APPLE__)
static const char *unixTempFileDir(void);

static int unixInvalidateSupportFiles(unixFile *pFile, int skipWAL) {
  char jPath[MAXPATHLEN+9];
  int zLen = strlcpy(jPath, pFile->zPath, MAXPATHLEN+9);
  if( zLen<MAXPATHLEN ){
    size_t jLen;
    const char extensions[3][9] = { "-wal", "-journal", "-shm" };
    int j = (skipWAL ? 1 : 0);
    for( ; j<3; j++ ){
      
      /* Check to see if the shm file is already opened for this pFile */
      if( j==2 ){
        unixEnterMutex(); /* Because pFile->pInode is shared across threads */
        unixShmNode *pShmNode = pFile->pInode->pShmNode;
        if( pShmNode && !pShmNode->isReadonly ){
          struct stat sStat;
          sqlite3_mutex_enter(pShmNode->mutex);
          
          if( pShmNode->h>=0 && !osFstat(pShmNode->h, &sStat) ){
            unsigned long size = (sStat.st_size<4) ? sStat.st_size : 4;
            if( size>0 ){
              bzero(pShmNode->apRegion[0], size);
              sqlite3_mutex_leave(pShmNode->mutex);
              unixLeaveMutex();
              continue;
            }
          }
          sqlite3_mutex_leave(pShmNode->mutex);
        }
        unixLeaveMutex();
      }
      jLen = strlcpy(&jPath[zLen], extensions[j], 9);
      if( jLen < 9 ){
        int jflags = (j<2) ? O_TRUNC : O_RDWR;
        int jfd = open(jPath, jflags);
        if( jfd==(-1) ){
          if( errno!=ENOENT ){
            perror(jPath);
          }
        } else {
          if( j==2 ){
            struct stat sStat;
            if( !osFstat(jfd, &sStat) ){
              unsigned long size = (sStat.st_size<4) ? sStat.st_size : 4;
              if( size>0 ){
                uint32_t zero = 0;
                pwrite(jfd, &zero, (size_t)size, 0);
              }
            }
          }
          fsync(jfd);
          close(jfd);
        }
      }
    }
  }
  return SQLITE_OK;
}

static int unixTruncateDatabase(unixFile *pFile, int bFlags) {
  sqlite3_file *id = (sqlite3_file *)pFile;
  int rc = SQLITE_OK;
  void *pLock = NULL;
  int flags = 0;
  int corruptFileLock = 0;
  int isCorrupt = 0;
    
#if SQLITE_ENABLE_DATA_PROTECTION
  flags |= pFile->protFlags;
#endif
#if SQLITE_ENABLE_LOCKING_STYLE
  if( isProxyLockingMode(pFile) ){
    flags |= SQLITE_OPEN_AUTOPROXY;
  }
#endif
  
  rc = sqlite3demo_superlock(pFile->zPath, 0, flags, 0, 0, &pLock);
  if( rc ){
    if( rc==SQLITE_CORRUPT || rc==SQLITE_NOTADB ){
      isCorrupt = 1;
      rc = sqlite3demo_superlock_corrupt(id, SQLITE_LOCK_EXCLUSIVE, &corruptFileLock);
    }
    if( rc ){
      return rc;
    }
  }
  if( bFlags!=0 ){
    /* initialize a new database in TMPDIR and copy the contents over */
    const char *tDir = unixTempFileDir();
    int tLen = sizeof(char) * (strlen(tDir) + 11);
    char *tDbPath = (char *)malloc(tLen);
    int tFd = -1;
    
    strlcpy(tDbPath, tDir, tLen);
    strlcat(tDbPath, "tmpdbXXXXX", tLen);
    tFd = mkstemp(tDbPath);
    if( tFd==-1 ){
      pFile->lastErrno=errno;
      rc = SQLITE_IOERR;
    }else{
      sqlite3 *tDb = NULL;
      copyfile_state_t s;
      int trc = sqlite3_open_v2(tDbPath, &tDb, SQLITE_OPEN_CREATE | SQLITE_OPEN_READWRITE | SQLITE_OPEN_AUTOPROXY, NULL);
      char *errmsg = NULL;
      const char *sql = "";
      if( !trc && (bFlags&SQLITE_TRUNCATE_PAGESIZE_MASK) ){
        const char pagesize_sql[4][22] = { "pragma page_size=1024", "pragma page_size=2048", "pragma page_size=4096", "pragma page_size=8192" };
        int iPagesize = (((bFlags&SQLITE_TRUNCATE_PAGESIZE_MASK) >> 4) - 1);
        assert( iPagesize>=0 && iPagesize<=4 );
        sql = pagesize_sql[iPagesize];
        trc = sqlite3_exec(tDb, sql, 0, 0, &errmsg);
      }
      if( !trc ){
        const char autovacuum_sql[3][21] = { "pragma auto_vacuum=0", "pragma auto_vacuum=1", "pragma auto_vacuum=2" };
        int iAutovacuum = 2; /* default to incremental */
        if( (bFlags&SQLITE_TRUNCATE_AUTOVACUUM_MASK) ){
          iAutovacuum = (((bFlags&SQLITE_TRUNCATE_AUTOVACUUM_MASK) >> 2) - 1);
        }
        assert( iAutovacuum>=0 && iAutovacuum<=2 );
        sql = autovacuum_sql[iAutovacuum];
        trc = sqlite3_exec(tDb, sql, 0, 0, &errmsg);
      }
      if( !trc && (bFlags&SQLITE_TRUNCATE_JOURNALMODE_WAL) ){
        sql = "pragma journal_mode=wal";
        trc = sqlite3_exec(tDb, sql, 0, 0, &errmsg);
      }
      if( trc ){
        if( !tDb ){
          fprintf(stderr, "failed to open temp database '%s' to reset truncated database %s with flags %x: %d\n", tDbPath, pFile->zPath, bFlags, trc);
        }else{
          fprintf(stderr, "failed to set '%s' on truncated database %s, %d: %s\n", sql, pFile->zPath, trc, errmsg);
        }
      }
      if( tDb ){
        sqlite3_close(tDb);
      }
      s = copyfile_state_alloc();
      lseek(tFd, 0, SEEK_SET);
      lseek(pFile->h, 0, SEEK_SET);
      if( fcopyfile(tFd, pFile->h, s, COPYFILE_ALL) ){
        int err=errno;
        switch(err) {
          case ENOMEM:
            rc = SQLITE_NOMEM;
            break;
          default:
            pFile->lastErrno = err;
            rc = SQLITE_IOERR;
        }
      }
      copyfile_state_free(s);
      fsync(pFile->h);
      close(tFd);
      unlink(tDbPath);
    }
    free(tDbPath);
  } else {
    rc = pFile->pMethod->xTruncate(id, ((pFile->fsFlags & SQLITE_FSFLAGS_IS_MSDOS) != 0) ? 1L : 0L);
  }
  if( rc==SQLITE_OK ){
    unixInvalidateSupportFiles(pFile, 0);
  }
  pFile->pMethod->xSync(id, SQLITE_SYNC_FULL);


  if( isCorrupt ){
    sqlite3demo_superunlock_corrupt(id, corruptFileLock);
  }else{
    sqlite3demo_superunlock(pLock);
  }
  return rc;
}

/*
 ** Lock locations for shared-memory locks used by WAL mode.
 */
#ifndef SHM_BASE
# define SHM_BASE          120
# define SHM_WRITE         SHM_BASE
# define SHM_CHECKPOINT    (SHM_BASE+1)
# define SHM_RECOVER       (SHM_BASE+2)
# define SHM_READ_FIRST    (SHM_BASE+3)
# define SHM_READ_SIZE     5
#endif /* SHM_BASE */

/*
** This test only works for lock testing on unix/posix VFS.
** Adapted from tool/getlock.c f4c39b651370156cae979501a7b156bdba50e7ce
*/
static int unixLockstatePid(unixFile *pFile, pid_t pid, int *pLockstate){
  int hDb;        /* File descriptor for the open database file */
  int hShm = -1;  /* File descriptor for WAL shared-memory file */
  ssize_t got;    /* Bytes read from header */
  int isWal;                 /* True if in WAL mode */
  int nLock = 0;             /* Number of locks held */
  unsigned char aHdr[100];   /* Database header */
  
  assert(pLockstate);
  
  /* make sure we are dealing with a database file */
  hDb = pFile->h;
  if( hDb<0 ){
    *pLockstate = SQLITE_LOCKSTATE_ERROR;
    return SQLITE_ERROR;
  }
  assert( (strlen(SQLITE_FILE_HEADER)+1)==SQLITE_FILE_HEADER_LEN );
  got = pread(hDb, aHdr, 100, 0);
  if( got<0 ){
    *pLockstate = SQLITE_LOCKSTATE_ERROR;
    return SQLITE_ERROR;
  }
  if( got!=100 || memcmp(aHdr, SQLITE_FILE_HEADER, SQLITE_FILE_HEADER_LEN)!=0 ){
    *pLockstate = SQLITE_LOCKSTATE_NOTADB;
    return SQLITE_NOTADB;
  }
  
  /* First check for an exclusive lock */
  nLock += unixIsLocked(pid, hDb, F_RDLCK, SHARED_FIRST, SHARED_SIZE, "EXCLUSIVE");
  isWal = aHdr[18]==2;
  if( nLock==0 && isWal==0 ){
    /* Rollback mode */
    nLock += unixIsLocked(pid, hDb, F_WRLCK, PENDING_BYTE, SHARED_SIZE+2, "PENDING|RESERVED|SHARED");
  }
  if( nLock==0 && isWal!=0 ){
    /* lookup the file descriptor for the shared memory file if we have it open in this process */
    unixEnterMutex(); /* Because pFile->pInode is shared across threads */
    unixShmNode *pShmNode = pFile->pInode->pShmNode;
    if( pShmNode ){
      sqlite3_mutex_enter(pShmNode->mutex);
      
      hShm = pShmNode->h;
      if( hShm >= 0){
        if( unixIsLocked(pid, hShm, F_RDLCK, SHM_RECOVER, 1, "WAL-RECOVERY") ||
           unixIsLocked(pid, hShm, F_RDLCK, SHM_WRITE, 1, "WAL-WRITE") ){
          nLock = 1;
        }
      }
      
      sqlite3_mutex_leave(pShmNode->mutex);
    } 
    
    if( hShm<0 ){
      /* the shared memory file isn't open in this process space, open our own FD */
      char zShm[MAXPATHLEN];
      
      /* WAL mode */
      strlcpy(zShm, pFile->zPath, MAXPATHLEN);
      strlcat(zShm, "-shm", MAXPATHLEN);
      hShm = open(zShm, O_RDONLY, 0);
      if( hShm<0 ){
        *pLockstate = SQLITE_LOCKSTATE_OFF;
        unixLeaveMutex();
        return SQLITE_OK;
      }
      if( unixIsLocked(pid, hShm, F_RDLCK, SHM_RECOVER, 1, "WAL-RECOVERY") ||
         unixIsLocked(pid, hShm, F_RDLCK, SHM_WRITE, 1, "WAL-WRITE") ){
        nLock = 1;
      }
      close(hShm);
    }
    unixLeaveMutex();
  }
  if( nLock>0 ){
    *pLockstate = SQLITE_LOCKSTATE_ON;
  } else {
    *pLockstate = SQLITE_LOCKSTATE_OFF;
  }
  return SQLITE_OK;
}

#endif /* (SQLITE_ENABLE_APPLE_SPI>0) && defined(__APPLE__) */



/*
** Here ends the implementation of all sqlite3_file methods.
**
********************** End sqlite3_file Methods *******************************
******************************************************************************/

  unixLock,                 /* xLock method */
  unixUnlock,               /* xUnlock method */
  unixCheckReservedLock     /* xCheckReservedLock method */
)
IOMETHODS(
  nolockIoFinder,           /* Finder function name */
  nolockIoMethods,          /* sqlite3_io_methods object name */
  2,                        /* shared memory is enabled */
  nolockClose,              /* xClose method */
  nolockLock,               /* xLock method */
  nolockUnlock,             /* xUnlock method */
  nolockCheckReservedLock   /* xCheckReservedLock method */
)
IOMETHODS(
  dotlockIoFinder,          /* Finder function name */

#endif
  }

  if( pLockingStyle == &posixIoMethods
#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
    || pLockingStyle == &nfsIoMethods
#endif
     /* support WAL mode on read only mounted filesystem */
    || pLockingStyle == &nolockIoMethods 
  ){
    unixEnterMutex();
    rc = findInodeInfo(pNew, &pNew->pInode);
    if( rc!=SQLITE_OK ){
      /* If an error occured in findInodeInfo(), close the file descriptor
      ** immediately, before releasing the mutex. findInodeInfo() may fail
      ** in two scenarios:

    int useProxy = 0;

    /* SQLITE_FORCE_PROXY_LOCKING==1 means force always use proxy, 0 means 
    ** never use proxy, NULL means use proxy for non-local files only.  */
    if( envforce!=NULL ){
      useProxy = atoi(envforce)>0;
    }else{













      useProxy = !(fsInfo.f_flags&MNT_LOCAL);
    }
    if( useProxy ){
      rc = fillInUnixFile(pVfs, fd, pFile, zPath, ctrlFlags);
      if( rc==SQLITE_OK ){
        /* cache the pMethod in case the transform fails */
        const struct sqlite3_io_methods *pMethod = pFile->pMethods;

** that the VFS encountered an error while handling the [PRAGMA] and the
** compilation of the PRAGMA fails with an error.  ^The [SQLITE_FCNTL_PRAGMA]
** file control occurs at the beginning of pragma statement analysis and so
** it is able to override built-in [PRAGMA] statements.
** </ul>
*/
#define SQLITE_FCNTL_LOCKSTATE               1
#define SQLITE_FCNTL_GET_LOCKPROXYFILE       2
#define SQLITE_FCNTL_SET_LOCKPROXYFILE       3
#define SQLITE_FCNTL_LAST_ERRNO              4
#define SQLITE_FCNTL_SIZE_HINT               5
#define SQLITE_FCNTL_CHUNK_SIZE              6
#define SQLITE_FCNTL_FILE_POINTER            7
#define SQLITE_FCNTL_SYNC_OMITTED            8
#define SQLITE_FCNTL_WIN32_AV_RETRY          9
#define SQLITE_FCNTL_PERSIST_WAL            10
#define SQLITE_FCNTL_OVERWRITE              11
#define SQLITE_FCNTL_VFSNAME                12
#define SQLITE_FCNTL_POWERSAFE_OVERWRITE    13
#define SQLITE_FCNTL_PRAGMA                 14
/* deprecated names */
#define SQLITE_GET_LOCKPROXYFILE      SQLITE_FCNTL_GET_LOCKPROXYFILE
#define SQLITE_SET_LOCKPROXYFILE      SQLITE_FCNTL_SET_LOCKPROXYFILE
#define SQLITE_LAST_ERRNO             SQLITE_FCNTL_LAST_ERRNO

/*
** CAPI3REF: Mutex Handle
**
** The mutex module within SQLite defines [sqlite3_mutex] to be an
** abstract type for a mutex object.  The SQLite core never looks
** at the internal representation of an [sqlite3_mutex].  It only

** locks by re-using open file descriptors for the database file and support
** files (-shm)
*/
#define SQLITE_FCNTL_LOCKSTATE_PID          103

/*
** Pass the SQLITE_TRUNCATE_DATABASE operation code to sqlite3_file_control() 
** to truncate a database and its associated journal file to zero length.  The 
** SQLITE_TRUNCATE_* flags represent optional flags to safely initialize an
** empty database in the place of the truncated database, the flags are passed 
** into sqlite3_file_control via the fourth argument using a pointer to an integer
** configured with the ORed flags.  If the fourth argument is NULL, the default 
** behavior is applied and the database file is truncated to zero bytes, a rollback 
** journal (if present) is unlinked, a WAL journal (if present) is truncated to zero 
** bytes and the first few bytes of the -shm file is scrambled to trigger existing
** connections to rebuild the index from the database file contents.
*/
#define SQLITE_FCNTL_TRUNCATE_DATABASE      101
#define SQLITE_TRUNCATE_DATABASE            SQLITE_FCNTL_TRUNCATE_DATABASE
#define SQLITE_TRUNCATE_JOURNALMODE_WAL           (0x1<<0)
#define SQLITE_TRUNCATE_AUTOVACUUM_MASK           (0x3<<2)
#define SQLITE_TRUNCATE_AUTOVACUUM_OFF            (0x1<<2)
#define SQLITE_TRUNCATE_AUTOVACUUM_FULL           (0x2<<2)
#define SQLITE_TRUNCATE_AUTOVACUUM_INCREMENTAL    (0x3<<2)
#define SQLITE_TRUNCATE_PAGESIZE_MASK             (0x7<<4)
#define SQLITE_TRUNCATE_PAGESIZE_1024             (0x1<<4)
#define SQLITE_TRUNCATE_PAGESIZE_2048             (0x2<<4)
#define SQLITE_TRUNCATE_PAGESIZE_4096             (0x3<<4)
#define SQLITE_TRUNCATE_PAGESIZE_8192             (0x4<<4)

/*
** Pass the SQLITE_REPLACE_DATABASE operation code to sqlite3_file_control() 
** and a sqlite3 pointer to another open database file to safely copy the 
** contents of that database file into the receiving database.
*/
#define SQLITE_FCNTL_REPLACE_DATABASE       102

  return TCL_OK;  
}

#ifdef __APPLE__
/* From sqlite3_priavet.h */
# ifndef SQLITE_TRUNCATE_DATABASE
# define SQLITE_TRUNCATE_DATABASE      101
# define SQLITE_TRUNCATE_JOURNALMODE_WAL           (0x1<<0)
# define SQLITE_TRUNCATE_AUTOVACUUM_MASK           (0x3<<2)
# define SQLITE_TRUNCATE_AUTOVACUUM_OFF            (0x1<<2)
# define SQLITE_TRUNCATE_AUTOVACUUM_FULL           (0x2<<2)
# define SQLITE_TRUNCATE_AUTOVACUUM_INCREMENTAL    (0x3<<2)
# define SQLITE_TRUNCATE_PAGESIZE_MASK             (0x7<<4)
# define SQLITE_TRUNCATE_PAGESIZE_1024             (0x1<<4)
# define SQLITE_TRUNCATE_PAGESIZE_2048             (0x2<<4)
# define SQLITE_TRUNCATE_PAGESIZE_4096             (0x3<<4)
# define SQLITE_TRUNCATE_PAGESIZE_8192             (0x4<<4)
# endif
# ifndef SQLITE_REPLACE_DATABASE
# define SQLITE_REPLACE_DATABASE       102
# endif

/*
** tclcmd:   file_control_truncate_test DB

*/
typedef struct WalWriter {
  Wal *pWal;                   /* The complete WAL information */
  sqlite3_file *pFd;           /* The WAL file to which we write */
  sqlite3_int64 iSyncPoint;    /* Fsync at this offset */
  int syncFlags;               /* Flags for the fsync */
  int szPage;                  /* Size of one page */
#if defined(SQLITE_WRITE_WALFRAME_PREBUFFERED)
  void *aFrameBuf;             /* Frame buffer */
  size_t szFrameBuf;           /* Size of frame buffer */
#endif
} WalWriter;

/*
** Write iAmt bytes of content into the WAL file beginning at iOffset.
** Do a sync when crossing the p->iSyncPoint boundary.
**
** In other words, if iSyncPoint is in between iOffset and iOffset+iAmt,

  WalWriter *p,               /* Where to write the frame */
  PgHdr *pPage,               /* The page of the frame to be written */
  int nTruncate,              /* The commit flag.  Usually 0.  >0 for commit */
  sqlite3_int64 iOffset       /* Byte offset at which to write */
){
  int rc;                         /* Result code from subfunctions */
  void *pData;                    /* Data actually written */
#if defined(SQLITE_WRITE_WALFRAME_PREBUFFERED)
  void *aFrame;

  assert(sizeof(p->aFrameBuf) == (p->szPage + WAL_FRAME_HDRSIZE));
  aFrame = p->aFrameBuf;
#else
  u8 aFrame[WAL_FRAME_HDRSIZE];   /* Buffer to assemble frame-header in */
#endif
  
#if defined(SQLITE_HAS_CODEC)
  if( (pData = sqlite3PagerCodec(pPage))==0 ) return SQLITE_NOMEM;
#else
  pData = pPage->pData;
#endif

  walEncodeFrame(p->pWal, pPage->pgno, nTruncate, pData, aFrame);
  
#if defined(SQLITE_WRITE_WALFRAME_PREBUFFERED)
  memcpy(&aFrame[WAL_FRAME_HDRSIZE], pData, p->szPage);
  rc = walWriteToLog(p, aFrame, (p->szPage + WAL_FRAME_HDRSIZE), iOffset);
#else
  rc = walWriteToLog(p, aFrame, sizeof(aFrame), iOffset);
  if( rc ) return rc;
  /* Write the page data */
  rc = walWriteToLog(p, pData, p->szPage, iOffset+sizeof(aFrame));
#endif
  return rc;
}

/* 
** Write a set of frames to the log. The caller must hold the write-lock
** on the log file (obtained using sqlite3WalBeginWriteTransaction()).
*/

  w.pWal = pWal;
  w.pFd = pWal->pWalFd;
  w.iSyncPoint = 0;
  w.syncFlags = sync_flags;
  w.szPage = szPage;
  iOffset = walFrameOffset(iFrame+1, szPage);
  szFrame = szPage + WAL_FRAME_HDRSIZE;
#if defined(SQLITE_WRITE_WALFRAME_PREBUFFERED)
  w.aFrameBuf = (void *)malloc(szFrame);
  if( NULL==w.aFrameBuf ){
    return SQLITE_NOMEM;
  }
#endif


  /* Write all frames into the log file exactly once */
  for(p=pList; p; p=p->pDirty){
    int nDbSize;   /* 0 normally.  Positive == commit flag */
    iFrame++;
    assert( iOffset==walFrameOffset(iFrame, szPage) );
    nDbSize = (isCommit && p->pDirty==0) ? nTruncate : 0;

        nExtra++;
      }
    }else{
      rc = sqlite3OsSync(w.pFd, sync_flags & SQLITE_SYNC_MASK);
    }
  }

#if defined(SQLITE_WRITE_WALFRAME_PREBUFFERED)
  free(w.aFrameBuf);
#endif
  /* If this frame set completes the first transaction in the WAL and
  ** if PRAGMA journal_size_limit is set, then truncate the WAL to the
  ** journal size limit, if possible.
  */
  if( isCommit && pWal->truncateOnCommit && pWal->mxWalSize>=0 ){
    i64 sz = pWal->mxWalSize;
    if( walFrameOffset(iFrame+nExtra+1, szPage)>pWal->mxWalSize ){

##########################################################################
# WAL mode.
#
ifcapable !wal {
  finish_test
  return
}
if ![wal_is_ok] { finish_test; return }

db close
forcedelete test.db
do_test 8_3_names-5.0 {
  sqlite3 db file:./test.db?8_3_names=1
  register_wholenumber_module db
  db eval {
    PRAGMA journal_mode=WAL;

foreach {name f} $files {
  if {[permutation] == "journaltest"} {
    set mode delete
  } else {
    set mode wal
  }
  ifcapable !wal { set mode delete }
  if ![wal_is_ok] { set mode delete }
  lappend L $mode
  append S "
    PRAGMA $name.journal_mode = WAL;
    UPDATE $name.tbl SET x = '$name';
  "
}
do_execsql_test 1.5 $S $L

} {0 {}}
do_test capi3-11.9.3 {
  sqlite3_get_autocommit $DB
} 1
do_test capi3-11.10 {
  sqlite3_step $STMT
} {SQLITE_ERROR}
ifcapable {autoreset} {
  do_test capi3-11.11 {
    sqlite3_step $STMT
  } {SQLITE_ROW}
  do_test capi3-11.12 {
    sqlite3_step $STMT
    sqlite3_step $STMT
  } {SQLITE_DONE}
  do_test capi3-11.13 {
    sqlite3_finalize $STMT
  } {SQLITE_OK}
}
do_test capi3-11.14 {
  execsql {
    SELECT a FROM t2;
  }
} {1 2}
do_test capi3-11.14.1 {
  sqlite3_get_autocommit $DB

} {0 {}}
do_test capi3c-11.9.3 {
  sqlite3_get_autocommit $DB
} 1
do_test capi3c-11.10 {
  sqlite3_step $STMT
} {SQLITE_ABORT}
ifcapable {autoreset} {
  do_test capi3c-11.11 {
    sqlite3_step $STMT
  } {SQLITE_ROW}
  do_test capi3c-11.12 {
    sqlite3_step $STMT
    sqlite3_step $STMT
  } {SQLITE_DONE}
  do_test capi3c-11.13 {
    sqlite3_finalize $STMT
  } {SQLITE_OK}
}
do_test capi3c-11.14 {
  execsql {
    SELECT a FROM t2;
  }
} {1 2}
do_test capi3c-11.14.1 {
  sqlite3_get_autocommit $DB

    DELETE FROM abc;
    PRAGMA incremental_vacuum;
    COMMIT;
  }
} {}

integrity_check incrvacuum2-3.3

if ![wal_is_ok] { finish_test; return }

ifcapable wal {
  # At one point, when a specific page was being extracted from the b-tree
  # free-list (e.g. during an incremental-vacuum), all trunk pages that
  # occurred before the specific page in the free-list trunk were being
  # written to the journal or wal file. This is not necessary. Only the 
  # extracted page and the page that contains the pointer to it need to

#   $sql: SQL to execute.
#   $res: Expected result of executing $sql.
#   $js:  The expected size of the journal file, in bytes, after executing
#         the SQL script. Or -1 if the journal is not expected to exist.
#   $ws:  The expected size of the WAL file, in bytes, after executing
#         the SQL script. Or -1 if the WAL is not expected to exist.
#
if {$::sqlite_options(wal) && [wal_is_ok]} {
  faultsim_delete_and_reopen
  foreach {tn sql res js ws} [subst {
  
    1  {
      CREATE TABLE t1(a, b);
      PRAGMA auto_vacuum=OFF;
      PRAGMA synchronous=NORMAL;

do_test pager1-20.2.2 {
  execsql {
    BEGIN EXCLUSIVE;
    COMMIT;
  }
} {}

if {$::sqlite_options(wal) && [wal_is_ok]} {
  do_test pager1-20.3.1 {
    faultsim_delete_and_reopen
    db func a_string a_string
    execsql {
      PRAGMA cache_size = 10;
      PRAGMA journal_mode = wal;
      BEGIN;

#-------------------------------------------------------------------------
# Test that a WAL database may not be opened if:
#
#   pager1-21.1.*: The VFS has an iVersion less than 2, or
#   pager1-21.2.*: The VFS does not provide xShmXXX() methods.
#
if {$::sqlite_options(wal) && [wal_is_ok]} {
  do_test pager1-21.0 {
    faultsim_delete_and_reopen
    execsql {
      PRAGMA journal_mode = WAL;
      CREATE TABLE ko(c DEFAULT 'abc', b DEFAULT 'def');
      INSERT INTO ko DEFAULT VALUES;
    }

#-------------------------------------------------------------------------
# Test that attempting to open a write-transaction with 
# locking_mode=exclusive in WAL mode fails if there are other clients on 
# the same database.
#
catch { db close }
if {$::sqlite_options(wal) && [wal_is_ok]} {
  do_multiclient_test tn {
    do_test pager1-28.$tn.1 {
      sql1 { 
        PRAGMA journal_mode = WAL;
        CREATE TABLE t1(a, b);
        INSERT INTO t1 VALUES('a', 'b');
      }

register_dbstat_vtab db
do_execsql_test stat-0.0 {
  PRAGMA auto_vacuum = OFF;
  CREATE VIRTUAL TABLE temp.stat USING dbstat;
  SELECT * FROM stat;
} {}

if {$::sqlite_options(wal) && [wal_is_ok]} {
  do_execsql_test stat-0.1 {
    PRAGMA journal_mode = WAL;
    PRAGMA journal_mode = delete;
    SELECT name, path, pageno, pagetype, ncell, payload, unused, mx_payload
      FROM stat;
  } {wal delete sqlite_master / 1 leaf 0 0 916 0}
}

#        handler returns 0 before said clients relinquish their locks.
#
#   6.*: Test that if a superlocked WAL database is overwritten, existing
#        clients run the recovery to build the new wal-index after the 
#        superlock is released.
#        
#

if {[forced_proxy_locking]} {
  finish_test 
  return 
}

do_execsql_test 1.1 {
  CREATE TABLE t1(a, b);
  INSERT INTO t1 VALUES(1, 2);
  PRAGMA journal_mode = DELETE;
} {delete}

#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix tkt-2d1a5c67d

ifcapable {!wal || !vtab} {finish_test; return}
if {![wal_is_ok]} {finish_test; return}

for {set ii 1} {$ii<=10} {incr ii} {
  do_test tkt-2d1a5c67d.1.$ii {
    db close
    forcedelete test.db test.db-wal
    sqlite3 db test.db
    db eval "PRAGMA cache_size=$::ii"

#

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

ifcapable !wal { finish_test ; return }
if ![wal_is_ok] { finish_test; return }

do_execsql_test tkt-313723c356.1 {
  PRAGMA page_size = 1024;
  PRAGMA journal_mode = WAL;
  CREATE TABLE t1(a, b);
  CREATE INDEX i1 ON t1(a, b);
  INSERT INTO t1 VALUES(randomblob(400), randomblob(400));

# This file implements tests to verify that ticket [5d863f876e] has been
# fixed.  
#

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

ifcapable !wal { finish_test; return }
if ![wal_is_ok] { finish_test; return }


do_multiclient_test tn {
  do_test $tn.1 {
    sql1 {
      CREATE TABLE t1(a, b);
      CREATE INDEX i1 ON t1(a, b);
      INSERT INTO t1 VALUES(1, 2);

source $testdir/lock_common.tcl
source $testdir/malloc_common.tcl
source $testdir/wal_common.tcl

set testprefix wal2

ifcapable !wal {finish_test ; return }
if ![wal_is_ok] {finish_test ; return }

set sqlite_sync_count 0
proc cond_incr_sync_count {adj} {
  global sqlite_sync_count
  if {$::tcl_platform(platform) == "windows"} {
    incr sqlite_sync_count $adj
  } {

proc incr_tvfs_hdr {file idx incrval} {
  set ints [set_tvfs_hdr $file]
  set v [lindex $ints $idx]
  incr v $incrval
  lset ints $idx $v
  set_tvfs_hdr $file $ints
}

set shmpath test.db-shm
if {[forced_proxy_locking]} {
  sqlite3 db test.db
  set shmpath [execsql { pragma lock_proxy_file }]-shm
  db close
}


#-------------------------------------------------------------------------
# Test case wal2-1.*:
#
# Set up a small database containing a single table. The database is not
# checkpointed during the test - all content resides in the log file.

  execsql {
    PRAGMA journal_mode = WAL;
    CREATE TABLE t1(a, b);
    PRAGMA wal_checkpoint;
    INSERT INTO t1 VALUES(1, 2);
    INSERT INTO t1 VALUES(3, 4);
  }
  if {[forced_proxy_locking]} {
    forcecopy $shmpath sv_test.db-shm
  }
  faultsim_save_and_close
} {}
do_test wal2-10.1.2 {
  faultsim_restore_and_reopen
  execsql { SELECT * FROM t1 }
} {1 2 3 4}
do_test wal2-10.1.3 {

#-------------------------------------------------------------------------
# If a connection is required to create a WAL or SHM file, it creates 
# the new files with the same file-system permissions as the database 
# file itself. Test this.
#
if {$::tcl_platform(platform) == "unix"} {
  if {[forced_proxy_locking]} {
    # faultsim_delete_and_reopen doesn't know about the shm file redirect...
    forcedelete $shmpath
  }
  
  faultsim_delete_and_reopen
  # Changed on 2012-02-13: umask is deliberately ignored for -wal files.
  #set umask [exec /bin/sh -c umask]
  set umask 0
  

  do_test wal2-12.1 {
    sqlite3 db test.db
    execsql { 
      CREATE TABLE tx(y, z);
      PRAGMA journal_mode = WAL;
    }
    db close
    list [file exists test.db-wal] [file exists $shmpath]
  } {0 0}
  
  foreach {tn permissions} {
   1 00644
   2 00666
   3 00600
   4 00755
  } {
    set effective [format %.5o [expr $permissions & ~$umask]]
    do_test wal2-12.2.$tn.1 {
      file attributes test.db -permissions $permissions
      file attributes test.db -permissions
    } $permissions
    do_test wal2-12.2.$tn.2 {
      list [file exists test.db-wal] [file exists $shmpath]
    } {0 0}
    do_test wal2-12.2.$tn.3 {
      sqlite3 db test.db
      execsql { INSERT INTO tx DEFAULT VALUES }
      list [file exists test.db-wal] [file exists $shmpath]
    } {1 1}
    do_test wal2-12.2.$tn.4 {
      list [file attr test.db-wal -perm] [file attr $shmpath -perm]
    } [list $effective $effective]
    do_test wal2-12.2.$tn.5 {
      db close
      list [file exists test.db-wal] [file exists $shmpath]
    } {0 0}
  }
}

#-------------------------------------------------------------------------
# Test the libraries response to discovering that one or more of the
# database, wal or shm files cannot be opened, or can only be opened
# read-only.
#
if {$::tcl_platform(platform) == "unix"} {
  proc perm {} {
    set L [list]
    foreach f {test.db test.db-wal $shmpath} {
      if {[file exists $f]} {
        lappend L [file attr $f -perm]
      } else {
        lappend L {}
      }
    }
    set L
  }

  if {[forced_proxy_locking]} {
    # faultsim_delete_and_reopen doesn't know about the shm file redirect...
    forcedelete $shmpath
  }
  faultsim_delete_and_reopen
  execsql {
    PRAGMA journal_mode = WAL;
    CREATE TABLE t1(a, b);
    PRAGMA wal_checkpoint;
    INSERT INTO t1 VALUES('3.14', '2.72');
  }
  do_test wal2-13.1.1 {
    list [file exists $shmpath] [file exists test.db-wal]
  } {1 1}
  if {[forced_proxy_locking]} {
    forcecopy $shmpath proxysv_test.db-shm 
  }
  faultsim_save_and_close

  foreach {tn db_perm wal_perm shm_perm can_open can_read can_write} {
    2   00644   00644   00644   1   1   1
    3   00644   00400   00644   1   1   0
    4   00644   00644   00400   1   0   0
    5   00400   00644   00644   1   1   0

    7   00644   00000   00644   1   0   0
    8   00644   00644   00000   1   0   0
    9   00000   00644   00644   0   0   0
  } {
    faultsim_restore
    if {[forced_proxy_locking]} {
      forcecopy proxysv_test.db-shm $shmpath  
    }
    do_test wal2-13.$tn.1 {
      file attr test.db     -perm $db_perm
      file attr test.db-wal -perm $wal_perm
      file attr $shmpath -perm $shm_perm

      set     L [file attr test.db -perm]
      lappend L [file attr test.db-wal -perm]
      lappend L [file attr $shmpath -perm]
    } [list $db_perm $wal_perm $shm_perm]

    # If $can_open is true, then it should be possible to open a database
    # handle. Otherwise, if $can_open is 0, attempting to open the db
    # handle throws an "unable to open database file" exception.
    #
    set r(1) {0 ok}

    catch { db close }
  }
}

#-------------------------------------------------------------------------
# Test that "PRAGMA checkpoint_fullsync" appears to be working.
#
foreach {tn sql reslist altreslist} {
  1 { }                                 {10 0 4 0 6 0} {7 4 3 2 3 2}
  2 { PRAGMA checkpoint_fullfsync = 1 } {10 4 4 2 6 2} {7 4 3 2 3 2}
  3 { PRAGMA checkpoint_fullfsync = 0 } {10 0 4 0 6 0} {7 0 3 0 3 0}
} {
  faultsim_delete_and_reopen

  execsql {PRAGMA auto_vacuum = 0}
  execsql $sql
  do_execsql_test wal2-14.$tn.0 { PRAGMA page_size = 4096 }   {}
  do_execsql_test wal2-14.$tn.1 { PRAGMA journal_mode = WAL } {wal}

  set sqlite_sync_count 0
  set sqlite_fullsync_count 0

  set useres $reslist
  if $::sqlite_options(default_wal_safetylevel) {
    set useres $altreslist
  }

  do_execsql_test wal2-14.$tn.2 {
    PRAGMA wal_autocheckpoint = 10;
    CREATE TABLE t1(a, b);                -- 2 wal syncs
    INSERT INTO t1 VALUES(1, 2);          -- 2 wal sync
    PRAGMA wal_checkpoint;                -- 1 wal sync, 1 db sync
    BEGIN;
      INSERT INTO t1 VALUES(3, 4);
      INSERT INTO t1 VALUES(5, 6);
    COMMIT;                               -- 2 wal sync
    PRAGMA wal_checkpoint;                -- 1 wal sync, 1 db sync
  } {10 0 3 3 0 1 1}

  do_test wal2-14.$tn.3 {
    cond_incr_sync_count 1
    list $sqlite_sync_count $sqlite_fullsync_count
  } [lrange $useres 0 1]

  set sqlite_sync_count 0
  set sqlite_fullsync_count 0

  do_test wal2-14.$tn.4 {
    execsql { INSERT INTO t1 VALUES(7, zeroblob(12*4096)) }
    list $sqlite_sync_count $sqlite_fullsync_count
  } [lrange $useres 2 3]

  set sqlite_sync_count 0
  set sqlite_fullsync_count 0

  do_test wal2-14.$tn.5 {
    execsql { PRAGMA wal_autocheckpoint = 1000 }
    execsql { INSERT INTO t1 VALUES(9, 10) }
    execsql { INSERT INTO t1 VALUES(11, 12) }
    execsql { INSERT INTO t1 VALUES(13, 14) }
    db close
    list $sqlite_sync_count $sqlite_fullsync_count
  } [lrange $useres 4 5]
}

catch { db close }

# PRAGMA checkpoint_fullsync
# PRAGMA fullfsync
# PRAGMA synchronous

set testdir [file dirname $argv0]
source $testdir/tester.tcl
source $testdir/lock_common.tcl
source $testdir/wal_common.tcl
source $testdir/malloc_common.tcl
ifcapable !wal {finish_test ; return }
if ![wal_is_ok] {finish_test ; return }

set a_string_counter 1
proc a_string {n} {
  global a_string_counter
  incr a_string_counter
  string range [string repeat "${a_string_counter}." $n] 1 $n
}

#   CREATE TABLE x(y);
#   INSERT INTO x VALUES('z');
#   PRAGMA wal_checkpoint;
#
# in WAL mode the xSync method is invoked as expected for each of
# synchronous=off, synchronous=normal and synchronous=full.
#
foreach {tn syncmode synccount altsynccount} {
  1 off     
    {}
    {}
  2 normal  
    {test.db-wal normal test.db normal}
    {test.db-wal full test.db full}
  3 full    
    {test.db-wal normal test.db-wal normal test.db-wal normal test.db normal}
    {test.db-wal normal test.db-wal normal test.db-wal full test.db full}
} {

  proc sync_counter {args} { 
    foreach {method filename id flags} $args break
    lappend ::syncs [file tail $filename] $flags
  }
  set usecount $synccount
  if $::sqlite_options(default_wal_safetylevel) {
    set usecount $altsynccount
  }

  do_test wal3-3.$tn {
    forcedelete test.db test.db-wal test.db-journal
  
    testvfs T
    T filter {} 
    T script sync_counter
    sqlite3 db test.db -vfs T

    execsql {
      CREATE TABLE x(y);
      INSERT INTO x VALUES('z');
      PRAGMA wal_checkpoint;
    }
    T filter {}
    set ::syncs
  } $usecount

  db close
  T delete
}

#-------------------------------------------------------------------------
# When recovering the contents of a WAL file, a process obtains the WRITER

#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
source $testdir/lock_common.tcl
source $testdir/wal_common.tcl
ifcapable !wal {finish_test ; return }
if ![wal_is_ok] { finish_test; return }

set testprefix wal5

proc db_page_count  {{file test.db}} { expr [file size $file] / 1024 }
proc wal_page_count {{file test.db}} { wal_frame_count ${file}-wal 1024 }

# focus of this file is testing the PRAGMA journal_size_limit when
# in WAL mode.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
ifcapable !wal {finish_test ; return }
if ![wal_is_ok] { finish_test; return }

# Case 1:  No size limit.  Journal can get large.
#
do_test wal7-1.0 {
  db close
  forcedelete test.db
  sqlite3 db test.db

# size from the database file as soon as it is opened (even before the
# first read transaction is executed), and the "PRAGMA page_size = XXX"
# is a no-op.
#
set testdir [file dirname $argv0]
source $testdir/tester.tcl
set ::testprefix wal8
ifcapable !wal {finish_test ; return }
if ![wal_is_ok] { finish_test; return }

db close
forcedelete test.db test.db-wal

sqlite3 db test.db
sqlite3 db2 test.db

source $testdir/tester.tcl
source $testdir/wal_common.tcl
source $testdir/malloc_common.tcl

do_not_use_codec

ifcapable !wal {finish_test ; return }
if { ![wal_is_ok] } { finish_test ; return }





# Test organization:
# 
#   walback-1.*: Simple tests.
#
#   walback-2.*: Test backups when the source db is modified mid-backup.

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

ifcapable !wal {
  finish_test
  return
}
if ![wal_is_ok] { finish_test; return }

# Do not use a codec for this file, as the database is manipulated using
# external methods (the [fake_big_file] and [hexio_write] commands).
#
do_not_use_codec

# If SQLITE_DISABLE_LFS is defined, omit this file.

set testdir [file dirname $argv0]
source $testdir/tester.tcl
source $testdir/lock_common.tcl
source $testdir/wal_common.tcl

ifcapable !wal {finish_test ; return }
if ![wal_is_ok] { finish_test; return }




# Read and return the contents of file $filename. Treat the content as
# binary data.
#
proc readfile {filename} {
  set fd [open $filename]
  fconfigure $fd -encoding binary

# walcrash-3.*: Recover multiple databases where the failed transaction 
#               was a multi-file transaction.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
ifcapable !wal {finish_test ; return }
if ![wal_is_ok] { finish_test; return }




db close

set seed 0
set REPEATS 100

# walcrash-1.*

# truncates the WAL file if "PRAGMA journal_size_limit" is configured.
#

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

ifcapable !wal {finish_test ; return }
if ![wal_is_ok] { finish_test; return }

set testprefix walcrash3

db close
testvfs tvfs
tvfs filter {xTruncate xWrite}
tvfs script tvfs_callback
proc tvfs_callback {args} {}

set testdir [file dirname $argv0]
source $testdir/tester.tcl
source $testdir/malloc_common.tcl
source $testdir/lock_common.tcl

ifcapable !wal {finish_test ; return }
if ![wal_is_ok] { finish_test; return }




#-------------------------------------------------------------------------
# This test case, walfault-1-*, simulates faults while executing a
#
#   PRAGMA journal_mode = WAL;
#
# statement immediately after creating a new database.

#

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

ifcapable !wal {finish_test ; return }
if ![wal_is_ok] { finish_test; return }




set ::wal_hook [list]
proc wal_hook {zDb nEntry} {
  lappend ::wal_hook $zDb $nEntry
  return 0
}
db wal_hook wal_hook

# using the xShm primitives if the connection is in exclusive-mode.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix walnoshm
ifcapable !wal {finish_test ; return }
if ![wal_is_ok] { finish_test; return }

db close
testvfs tvfsshm
testvfs tvfs -default 1 -iversion 1 
sqlite3 db test.db

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

source $testdir/lock_common.tcl
set ::testprefix walpersist

ifcapable !wal {
  finish_test
  return
}
if ![wal_is_ok] { finish_test; return }

set shmpath test.db-shm
if {[forced_proxy_locking]} {
  set shmpath [execsql { pragma lock_proxy_file }]-shm
}

do_test walpersist-1.0 {
  db eval {
    PRAGMA journal_mode=WAL;
    CREATE TABLE t1(a);
    INSERT INTO t1 VALUES(randomblob(5000));
  }
  file exists test.db-wal
} {1}
do_test walpersist-1.1 {
  file exists $shmpath
} {1}
do_test walpersist-1.2 {
  db close
  list [file exists test.db] [file exists test.db-wal] [file exists $shmpath]
} {1 0 0}
do_test walpersist-1.3 {
  sqlite3 db test.db
  db eval {SELECT length(a) FROM t1}
} {5000}
do_test walpersist-1.4 {
  list [file exists test.db] [file exists test.db-wal] [file exists $shmpath]
} {1 1 1}
do_test walpersist-1.5 {
  file_control_persist_wal db -1
} {0 0}
do_test walpersist-1.6 {
  file_control_persist_wal db 1
} {0 1}

  file_control_persist_wal db -1
} {0 0}
do_test walpersist-1.10 {
  file_control_persist_wal db 1
} {0 1}
do_test walpersist-1.11 {
  db close
  list [file exists test.db] [file exists test.db-wal] [file exists $shmpath]
} {1 1 1}

# Make sure the journal_size_limit works to limit the size of the
# persisted wal file.  In persistent-wal mode, any non-negative
# journal_size_limit causes the WAL file to be truncated to zero bytes
# when closing.
#
forcedelete test.db $shmpath test.db-wal
do_test walpersist-2.1 {
  sqlite3 db test.db
  db eval {
    PRAGMA journal_mode=WAL;
    PRAGMA wal_autocheckpoint=OFF;
    PRAGMA journal_size_limit=12000;
    CREATE TABLE t1(x);

do_test walpersist-2.3 {
  sqlite3 db test.db
  execsql { PRAGMA integrity_check }
} {ok}

do_test 3.1 {
  catch {db close}
  forcedelete test.db $shmpath test.db-wal
  sqlite3 db test.db
  execsql {
    PRAGMA page_size = 1024;
    PRAGMA journal_mode = WAL;
    PRAGMA wal_autocheckpoint=128;
    PRAGMA journal_size_limit=16384;
    CREATE TABLE t1(a, b, PRIMARY KEY(a, b));

# And only if the build is WAL-capable.
#
ifcapable !wal {
  finish_test
  return
}
if ![wal_is_ok] { finish_test; return }

set shmpath test.db-shm
if {[forced_proxy_locking]} {
  sqlite3 db test.db
  set shmpath [execsql { pragma lock_proxy_file }]-shm
  db close
}

do_multiclient_test tn {
  # Do not run tests with the connections in the same process.
  #
  if {$tn==2} continue
  
  # Close all connections and delete the database.

  do_test 1.1.1 {
    code2 { sqlite3 db2 test.db }
    sql2 { 
      PRAGMA journal_mode = WAL;
      CREATE TABLE t1(x, y);
      INSERT INTO t1 VALUES('a', 'b');
    }
    file exists $shmpath
  } {1}

  do_test 1.1.2 {
    file attributes $shmpath -permissions r--r--r--
    code1 { sqlite3 db file:test.db?readonly_shm=1 }
  } {}

  do_test 1.1.3 { sql1 "SELECT * FROM t1" }                {a b}
  do_test 1.1.4 { sql2 "INSERT INTO t1 VALUES('c', 'd')" } {}
  do_test 1.1.5 { sql1 "SELECT * FROM t1" }                {a b c d}

  } {}
  do_test 1.1.12 { sql1 "SELECT * FROM t1" }                {a b c d e f g h}
  do_test 1.1.13  { sql2 "INSERT INTO t1 VALUES('i', 'j')" } {}

  do_test 1.2.1 {
    code2 { db2 close }
    code1 { db close }
    list [file exists test.db-wal] [file exists $shmpath]
  } {1 1}
  do_test 1.2.2 {
    code1 { sqlite3 db file:test.db?readonly_shm=1 }
    sql1 { SELECT * FROM t1 }
  } {a b c d e f g h i j}

  do_test 1.2.3 {
    code1 { db close }
    file attributes $shmpath -permissions rw-r--r--
    hexio_write $shmpath 0 01020304
    file attributes $shmpath -permissions r--r--r--
    code1 { sqlite3 db file:test.db?readonly_shm=1 }
    csql1 { SELECT * FROM t1 }
  } {1 {attempt to write a readonly database}}
  do_test 1.2.4 {
    code1 { sqlite3_extended_errcode db } 
  } {SQLITE_READONLY_RECOVERY}

  do_test 1.2.5 {
    file attributes $shmpath -permissions rw-r--r--
    code2 { sqlite3 db2 test.db }
    sql2 "SELECT * FROM t1" 
  } {a b c d e f g h i j}
  file attributes $shmpath -permissions r--r--r--
  do_test 1.2.6 { sql1 "SELECT * FROM t1" } {a b c d e f g h i j}

  do_test 1.2.7 { 
    sql2 {
      PRAGMA wal_checkpoint;
      INSERT INTO t1 VALUES('k', 'l');
    }

  } {1 {unable to open database file}}

  # Also test that if the -shm file can be opened for read/write access,
  # it is not if readonly_shm=1 is present in the URI.
  do_test 1.3.2.1 {
    code1 { db close }
    code2 { db2 close }
    file exists $shmpath
  } {0}
  do_test 1.3.2.2 {
    code1 { sqlite3 db file:test.db?readonly_shm=1 }
    csql1 { SELECT * FROM sqlite_master }
  } {1 {unable to open database file}}
  do_test 1.3.2.3 {
    code1 { db close }
    close [open $shmpath w]
    file attributes $shmpath -permissions r--r--r--
    code1 { sqlite3 db file:test.db?readonly_shm=1 }
    csql1 { SELECT * FROM t1 }
  } {1 {attempt to write a readonly database}}
  do_test 1.3.2.4 {
    code1 { sqlite3_extended_errcode db } 
  } {SQLITE_READONLY_RECOVERY}
}

forcedelete $shmpath

finish_test

# "PRAGMA journal_mode=WAL" mode with shared-cache turned on.
#

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

ifcapable !wal {finish_test ; return }
if ![wal_is_ok] { finish_test; return }

db close
set ::enable_shared_cache [sqlite3_enable_shared_cache 1]

sqlite3 db  test.db
sqlite3 db2 test.db

# brute force methods, so may take a while to run.
#

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

ifcapable !wal {finish_test ; return }
if ![wal_is_ok] { finish_test; return }




proc reopen_db {} {
  catch { db close }
  forcedelete test.db test.db-wal
  sqlite3 db test.db
  execsql { PRAGMA journal_mode = wal }
}

set testdir [file dirname $argv0]

source $testdir/tester.tcl
source $testdir/lock_common.tcl
if {[run_thread_tests]==0} { finish_test ; return }
ifcapable !wal             { finish_test ; return }
if ![wal_is_ok] { finish_test; return }




set sqlite_walsummary_mmap_incr 64

# How long, in seconds, to run each test for. If a test is set to run for
# 0 seconds, it is omitted entirely.
#
unset -nocomplain seconds