SQLite

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
******************************************************************************
**
** This file contains code that is specific to Unix systems.
**
** $Id: os_unix.c,v 1.217 2008/11/21 00:10:35 aswift Exp $
*/
#include "sqliteInt.h"
#if SQLITE_OS_UNIX              /* This file is used on unix only */

/*
** If SQLITE_ENABLE_LOCKING_STYLE is defined and is non-zero, then several
** alternative locking implementations are provided:
**
**   * POSIX locking (the default),
**   * No locking,
**   * Dot-file locking,
**   * flock() locking,
**   * AFP locking (OSX only),
**   * Named POSIX semaphores (VXWorks only),
**   * proxy locking.
**
** SQLITE_ENABLE_LOCKING_STYLE only works on a Mac. It is turned on by
** default on a Mac and disabled on all other posix platforms.
*/
#if !defined(SQLITE_ENABLE_LOCKING_STYLE)
#  if defined(__DARWIN__)
#    define SQLITE_ENABLE_LOCKING_STYLE 1

/*
** Default permissions when creating a new file
*/
#ifndef SQLITE_DEFAULT_FILE_PERMISSIONS
# define SQLITE_DEFAULT_FILE_PERMISSIONS 0644
#endif

/*
 ** Default permissions when creating auto proxy dir
 */
#ifndef SQLITE_DEFAULT_PROXYDIR_PERMISSIONS
# define SQLITE_DEFAULT_PROXYDIR_PERMISSIONS 0755
#endif

/*
** Maximum supported path-length.
*/
#define MAX_PATHNAME 512


/*

  pthread_t tid;            /* The thread that "owns" this unixFile */
#endif
  int lastErrno;            /* The unix errno from the last I/O error */
#if IS_VXWORKS
  int isDelete;             /* Delete on close if true */
  char *zRealpath;
#endif
#if SQLITE_ENABLE_LOCKING_STYLE
  int oflags;               /* The flags specified at open */
#endif
};

/*
** Include code that is common to all os_*.c files
*/
#include "os_common.h"

**
** POSIX locking style fully supports shared and exclusive byte-range locks 
** AFP locking only supports exclusive byte-range locks
** FLOCK only supports a single file-global exclusive lock
** DOTLOCK isn't a true locking style, it refers to the use of a special
**   file named the same as the database file with a '.lock' extension, this
**   can be used on file systems that do not offer any reliable file locking
** NONE locking means that no locking will be attempted, this is only used for
**   read-only file systems currently
** NAMEDSEM is similar to DOTLOCK but uses a named semaphore instead of an
**   indicator file.
** PROXY uses a second file to represent the lock state of the database file
**   which is never actually locked, a third file controls access to the proxy
** UNSUPPORTED means that no locking will be attempted, this is only used for
**   file systems that are known to be unsupported
*/
#define LOCKING_STYLE_POSIX        1
#define LOCKING_STYLE_NONE         2
#define LOCKING_STYLE_DOTFILE      3
#define LOCKING_STYLE_FLOCK        4
#define LOCKING_STYLE_AFP          5
#define LOCKING_STYLE_NAMEDSEM     6
#define LOCKING_STYLE_PROXY        7

/*
** Only set the lastErrno if the error code is a real error and not 
** a normal expected return code of SQLITE_BUSY or SQLITE_OK
*/
#define IS_LOCK_ERROR(x)  ((x != SQLITE_OK) && (x != SQLITE_BUSY))

  }
  strcpy(result, workpath);
  return result;
}
#endif

#if SQLITE_ENABLE_LOCKING_STYLE
/*
** The proxyLockingContext has the path and file structures for the remote 
** and local proxy files in it
*/
typedef struct proxyLockingContext proxyLockingContext;
struct proxyLockingContext {
  unixFile *conchFile;
  char *conchFilePath;
  unixFile *lockProxy;
  char *lockProxyPath;
  char *dbPath;
  int conchHeld;
  void *oldLockingContext; /* preserve the original locking context for close */
  sqlite3_io_methods const *pOldMethod; /* ditto pMethod */
};

static int getDbPathForUnixFile(unixFile *pFile, char *dbPath);
static int getLockPath(const char *dbPath, char *lPath, size_t maxLen);
static sqlite3_io_methods *ioMethodForLockingStyle(int style);
static int createProxyUnixFile(const char *path, unixFile **ppFile);
static int fillInUnixFile(sqlite3_vfs *pVfs, int h, int dirfd, sqlite3_file *pId, const char *zFilename, int noLock, int isDelete);
static int takeConch(unixFile *pFile);
static int releaseConch(unixFile *pFile);
static int unixRandomness(sqlite3_vfs *pVfs, int nBuf, char *zBuf);

/*
** Tests a byte-range locking query to see if byte range locks are 
** supported, if not we fall back to dotlockLockingStyle.
** On vxWorks we fall back to namedsemLockingStyle.
*/
static int testLockingStyle(int fd){
  struct flock lockInfo;

    { "ufs",    LOCKING_STYLE_POSIX },
    { "afpfs",  LOCKING_STYLE_AFP },
#ifdef SQLITE_ENABLE_AFP_LOCKING_SMB
    { "smbfs",  LOCKING_STYLE_AFP },
#else
    { "smbfs",  LOCKING_STYLE_FLOCK },
#endif

    { "webdav", LOCKING_STYLE_NONE },
    { 0, 0 }
  };
  int i;
  struct statfs fsInfo;

  if( !filePath ){
    return LOCKING_STYLE_NONE;
  }
  if( pVfs && pVfs->pAppData ){
    return SQLITE_PTR_TO_INT(pVfs->pAppData);
  }

  if( statfs(filePath, &fsInfo) != -1 ){
    if( fsInfo.f_flags & MNT_RDONLY ){
      return LOCKING_STYLE_NONE;
    }

  /* Default case. Handles, amongst others, "nfs". */
  return testLockingStyle(fd);  
#endif /* if IS_VXWORKS */
  return LOCKING_STYLE_POSIX;
}
#else
  #define detectLockingStyle(x,y,z) LOCKING_STYLE_POSIX
#endif /* if SQLITE_ENABLE_LOCKING_STYLE */

/*
** Given a file descriptor, locate lockInfo and openCnt structures that
** describes that file descriptor.  Create new ones if necessary.  The
** return values might be uninitialized if an error occurs.
**
** Return an appropriate error code.
*/
static int findLockInfo(
  unixFile *pFile,             /* Unix file with file desc used in the key */
#if IS_VXWORKS
  void *rnam,                  /* vxWorks realname */
#endif
  struct lockInfo **ppLock,    /* Return the lockInfo structure here */
  struct openCnt **ppOpen      /* Return the openCnt structure here */
){
  int rc;
  int fd;
  struct lockKey key1;
  struct openKey key2;
  struct stat statbuf;
  struct lockInfo *pLock;
  struct openCnt *pOpen;
  fd = pFile->h;
  rc = fstat(fd, &statbuf);
  if( rc!=0 ){
    pFile->lastErrno = errno;
#ifdef EOVERFLOW
    if( pFile->lastErrno==EOVERFLOW ) return SQLITE_NOLFS;
#endif
    return SQLITE_IOERR;
  }

  /* On OS X on an msdos filesystem, the inode number is reported
  ** incorrectly for zero-size files.  See ticket #3260.  To work
  ** around this problem (we consider it a bug in OS X, not SQLite)
  ** we always increase the file size to 1 by writing a single byte
  ** prior to accessing the inode number.  The one byte written is
  ** an ASCII 'S' character which also happens to be the first byte
  ** in the header of every SQLite database.  In this way, if there
  ** is a race condition such that another thread has already populated
  ** the first page of the database, no damage is done.
  */
  if( statbuf.st_size==0 ){
    write(fd, "S", 1);
    rc = fstat(fd, &statbuf);
    if( rc!=0 ){
      pFile->lastErrno = errno;
      return SQLITE_IOERR;
    }
  }

  memset(&key1, 0, sizeof(key1));
  key1.dev = statbuf.st_dev;
#if IS_VXWORKS

  memset(&key2, 0, sizeof(key2));
  key2.dev = statbuf.st_dev;
#if IS_VXWORKS
  key2.rnam = rnam;
#else
  key2.ino = statbuf.st_ino;
#endif
  if( ppLock!=0 ){
    pLock = lockList;
    while( pLock && memcmp(&key1, &pLock->key, sizeof(key1)) ){
      pLock = pLock->pNext;
    }
    if( pLock==0 ){
      pLock = sqlite3_malloc( sizeof(*pLock) );
      if( pLock==0 ){
        rc = SQLITE_NOMEM;
        goto exit_findlockinfo;
      }
      pLock->key = key1;
      pLock->nRef = 1;
      pLock->cnt = 0;
      pLock->locktype = 0;
      pLock->pNext = lockList;
      pLock->pPrev = 0;
      if( lockList ) lockList->pPrev = pLock;
      lockList = pLock;
    }else{
      pLock->nRef++;
    }
    *ppLock = pLock;
  }
  if( ppOpen!=0 ){
    pOpen = openList;
    while( pOpen && memcmp(&key2, &pOpen->key, sizeof(key2)) ){
      pOpen = pOpen->pNext;
    }
    if( pOpen==0 ){
      pOpen = sqlite3_malloc( sizeof(*pOpen) );

  }
  OSTRACE4("Transfer ownership of %d from %d to %d\n",
            pFile->h, pFile->tid, hSelf);
  pFile->tid = hSelf;
  if (pFile->pLock != NULL) {
    releaseLockInfo(pFile->pLock);
#if IS_VXWORKS
    rc = findLockInfo(pFile, pFile->zRealpath, &pFile->pLock, 0);
#else
    rc = findLockInfo(pFile, &pFile->pLock, 0);
#endif
    OSTRACE5("LOCK    %d is now %s(%s,%d)\n", pFile->h,
           locktypeName(pFile->locktype),
           locktypeName(pFile->pLock->locktype), pFile->pLock->cnt);
    return rc;
  } else {
    return SQLITE_OK;

** bytes into pBuf. Return the number of bytes actually read.
**
** NB:  If you define USE_PREAD or USE_PREAD64, then it might also
** be necessary to define _XOPEN_SOURCE to be 500.  This varies from
** one system to another.  Since SQLite does not define USE_PREAD
** any any form by default, we will not attempt to define _XOPEN_SOURCE.
** See tickets #2741 and #2681.
**
** To avoid stomping the errno value on a failed read the lastErrno value
** is set before returning.
*/
static int seekAndRead(unixFile *id, sqlite3_int64 offset, void *pBuf, int cnt){
  int got;
  i64 newOffset;
  TIMER_START;
#if defined(USE_PREAD)
  got = pread(id->h, pBuf, cnt, offset);
  SimulateIOError( got = -1 );
#elif defined(USE_PREAD64)
  got = pread64(id->h, pBuf, cnt, offset);
  SimulateIOError( got = -1 );
#else
  newOffset = lseek(id->h, offset, SEEK_SET);
  SimulateIOError( newOffset-- );
  if( newOffset!=offset ){
    if( newOffet == -1 ){
      ((unixFile*)id)->lastErrno = errno;
    }else{
      ((unixFile*)id)->lastErrno = 0;			
    }
    return -1;
  }
  got = read(id->h, pBuf, cnt);
#endif
  TIMER_END;
  if( got<0 ){
    ((unixFile*)id)->lastErrno = errno;
  }
  OSTRACE5("READ    %-3d %5d %7lld %llu\n", id->h, got, offset, TIMER_ELAPSED);
  return got;
}

/*
** Read data from a file into a buffer.  Return SQLITE_OK if all
** bytes were read successfully and SQLITE_IOERR if anything goes

){
  int got;
  assert( id );
  got = seekAndRead((unixFile*)id, offset, pBuf, amt);
  if( got==amt ){
    return SQLITE_OK;
  }else if( got<0 ){
    /* lastErrno set by seekAndRead */
    return SQLITE_IOERR_READ;
  }else{
    ((unixFile*)id)->lastErrno = 0; /* not a system error */
    /* Unread parts of the buffer must be zero-filled */
    memset(&((char*)pBuf)[got], 0, amt-got);
    return SQLITE_IOERR_SHORT_READ;
  }
}

/*
** Seek to the offset in id->offset then read cnt bytes into pBuf.
** Return the number of bytes actually read.  Update the offset.
**
** To avoid stomping the errno value on a failed write the lastErrno value
** is set before returning.
*/
static int seekAndWrite(unixFile *id, i64 offset, const void *pBuf, int cnt){
  int got;
  i64 newOffset;
  TIMER_START;
#if defined(USE_PREAD)
  got = pwrite(id->h, pBuf, cnt, offset);
#elif defined(USE_PREAD64)
  got = pwrite64(id->h, pBuf, cnt, offset);
#else
  newOffset = lseek(id->h, offset, SEEK_SET);
  if( newOffset!=offset ){
    if( newOffet == -1 ){
      ((unixFile*)id)->lastErrno = errno;
    }else{
      ((unixFile*)id)->lastErrno = 0;			
    }
    return -1;
  }
  got = write(id->h, pBuf, cnt);
#endif
  TIMER_END;
  if( got<0 ){
    ((unixFile*)id)->lastErrno = errno;
  }

  OSTRACE5("WRITE   %-3d %5d %7lld %llu\n", id->h, got, offset, TIMER_ELAPSED);
  return got;
}


/*
** Write data from a buffer into a file.  Return SQLITE_OK on success

    offset += wrote;
    pBuf = &((char*)pBuf)[wrote];
  }
  SimulateIOError(( wrote=(-1), amt=1 ));
  SimulateDiskfullError(( wrote=0, amt=1 ));
  if( amt>0 ){
    if( wrote<0 ){
      /* lastErrno set by seekAndWrite */
      return SQLITE_IOERR_WRITE;
    }else{
      ((unixFile*)id)->lastErrno = 0; /* not a system error */
      return SQLITE_FULL;
    }
  }
  return SQLITE_OK;
}

#ifdef SQLITE_TEST

  SimulateDiskfullError( return SQLITE_FULL );

  assert( pFile );
  OSTRACE2("SYNC    %-3d\n", pFile->h);
  rc = full_fsync(pFile->h, isFullsync, isDataOnly);
  SimulateIOError( rc=1 );
  if( rc ){
    pFile->lastErrno = errno;
    return SQLITE_IOERR_FSYNC;
  }
  if( pFile->dirfd>=0 ){
    int err;
    OSTRACE4("DIRSYNC %-3d (have_fullfsync=%d fullsync=%d)\n", pFile->dirfd,
            HAVE_FULLFSYNC, isFullsync);
#ifndef SQLITE_DISABLE_DIRSYNC
    /* The directory sync is only attempted if full_fsync is
    ** turned off or unavailable.  If a full_fsync occurred above,
    ** then the directory sync is superfluous.
    */
    if( (!HAVE_FULLFSYNC || !isFullsync) && full_fsync(pFile->dirfd,0,0) ){
       /*
       ** We have received multiple reports of fsync() returning
       ** errors when applied to directories on certain file systems.
       ** A failed directory sync is not a big deal.  So it seems
       ** better to ignore the error.  Ticket #1657
       */
       /* pFile->lastErrno = errno; */
       /* return SQLITE_IOERR; */
    }
#endif
    err = close(pFile->dirfd); /* Only need to sync once, so close the */
    if( err==0 ){              /* directory when we are done */
      pFile->dirfd = -1;
    }else{
      pFile->lastErrno = errno;
      rc = SQLITE_IOERR_DIR_CLOSE;
    }
  }
  return rc;
}

/*
** Truncate an open file to a specified size
*/
static int unixTruncate(sqlite3_file *id, i64 nByte){
  int rc;
  assert( id );
  SimulateIOError( return SQLITE_IOERR_TRUNCATE );
  rc = ftruncate(((unixFile*)id)->h, (off_t)nByte);
  if( rc ){
    ((unixFile*)id)->lastErrno = errno;
    return SQLITE_IOERR_TRUNCATE;
  }else{
    return SQLITE_OK;
  }
}

/*
** Determine the current size of a file in bytes
*/
static int unixFileSize(sqlite3_file *id, i64 *pSize){
  int rc;
  struct stat buf;
  assert( id );
  rc = fstat(((unixFile*)id)->h, &buf);
  SimulateIOError( rc=1 );
  if( rc!=0 ){
    ((unixFile*)id)->lastErrno = errno;
    return SQLITE_IOERR_FSTAT;
  }
  *pSize = buf.st_size;

  /* When opening a zero-size database, the findLockInfo() procedure
  ** writes a single byte into that file in order to work around a bug
  ** in the OS-X msdos filesystem.  In order to avoid problems with upper

    if( rc==SQLITE_OK ){
      pOpen = pFile->pOpen;
      pOpen->nLock--;
      assert( pOpen->nLock>=0 );
      if( pOpen->nLock==0 && pOpen->nPending>0 ){
        int i;
        for(i=0; i<pOpen->nPending; i++){
          /* close pending fds, but if closing fails don't free the array
          ** assign -1 to the successfully closed descriptors and record the
          ** error.  The next attempt to unlock will try again. */
          if( pOpen->aPending[i] < 0 ) continue;
          if( close(pOpen->aPending[i]) ){
            pFile->lastErrno = errno;
            rc = SQLITE_IOERR_CLOSE;
          }else{
            pOpen->aPending[i] = -1;
          }
        }
        if( rc==SQLITE_OK ){
          sqlite3_free(pOpen->aPending);
          pOpen->nPending = 0;
          pOpen->aPending = 0;
        }
      }
    }
  }
	
end_unlock:
  leaveMutex();
  if( rc==SQLITE_OK ) pFile->locktype = locktype;
  return rc;
}

/*
** This function performs the parts of the "close file" operation 
** common to all locking schemes. It closes the directory and file
** handles, if they are valid, and sets all fields of the unixFile
** structure to 0.
*/
static int closeUnixFile(sqlite3_file *id){
  unixFile *pFile = (unixFile*)id;
  if( pFile ){
    if( pFile->dirfd>=0 ){
      int err = close(pFile->dirfd);
      if( err ){
        pFile->lastErrno = errno;
        return SQLITE_IOERR_DIR_CLOSE;
      }else{
        pFile->dirfd=-1;
      }
    }
    if( pFile->h>=0 ){
      int err = close(pFile->h);
      if( err ){
        pFile->lastErrno = errno;
        return SQLITE_IOERR_CLOSE;
      }
    }
#if IS_VXWORKS
    if( pFile->isDelete && pFile->zRealpath ){
      unlink(pFile->zRealpath);
    }
    if( pFile->zRealpath ){
      HashElem *pElem;

  return SQLITE_OK;
}

/*
** Close a file.
*/
static int unixClose(sqlite3_file *id){
  int rc = SQLITE_OK;
  if( id ){
    unixFile *pFile = (unixFile *)id;
    unixUnlock(id, NO_LOCK);
    enterMutex();
    if( pFile->pOpen && pFile->pOpen->nLock ){
      /* If there are outstanding locks, do not actually close the file just
      ** yet because that would clear those locks.  Instead, add the file

        pOpen->aPending[pOpen->nPending] = pFile->h;
        pOpen->nPending++;
        pFile->h = -1;
      }
    }
    releaseLockInfo(pFile->pLock);
    releaseOpenCnt(pFile->pOpen);
    rc = closeUnixFile(id);
    leaveMutex();
  }
  return rc;
}


#if SQLITE_ENABLE_LOCKING_STYLE

#if !IS_VXWORKS
#pragma mark AFP support

/*
 ** The afpLockingContext structure contains all afp lock specific state
 */
typedef struct afpLockingContext afpLockingContext;
struct afpLockingContext {
  unsigned long long sharedByte;
  const char *dbPath;
};

struct ByteRangeLockPB2
{
  unsigned long long offset;        /* offset to first byte to lock */
  unsigned long long length;        /* nbr of bytes to lock */
  unsigned long long retRangeStart; /* nbr of 1st byte locked if successful */

  int                     err;
  
  pb.unLockFlag = setLockFlag ? 0 : 1;
  pb.startEndFlag = 0;
  pb.offset = offset;
  pb.length = length; 
  pb.fd = pFile->h;
  //SimulateIOErrorBenign(1);
  //SimulateIOError( pb.fd=(-1) )
  //SimulateIOErrorBenign(0);
  
  OSTRACE6("AFPSETLOCK [%s] for %d%s in range %llx:%llx\n", 
    (setLockFlag?"ON":"OFF"), pFile->h, (pb.fd==-1?"[testval-1]":""), offset, length);
  err = fsctl(path, afpfsByteRangeLock2FSCTL, &pb, 0);
  if ( err==-1 ) {
    int rc;
    int tErrno = errno;
    OSTRACE4("AFPSETLOCK failed to fsctl() '%s' %d %s\n", path, tErrno, strerror(tErrno));
#ifdef SQLITE_IGNORE_AFP_LOCK_ERRORS
    rc = SQLITE_BUSY;
#else
    rc = sqliteErrorFromPosixError(tErrno, setLockFlag ? SQLITE_IOERR_LOCK : SQLITE_IOERR_UNLOCK);
#endif /* SQLITE_IGNORE_AFP_LOCK_ERRORS */
    if( IS_LOCK_ERROR(rc) ){
      pFile->lastErrno = tErrno;
    }
    return rc;
  } else {
    return SQLITE_OK;
  }

    reserved = 1;
  }
  
  /* Otherwise see if some other process holds it.
   */
  if( !reserved ){
    /* lock the RESERVED byte */
    int lrc = _AFPFSSetLock(context->dbPath, pFile, RESERVED_BYTE, 1,1);  
    if( SQLITE_OK==lrc ){
      /* if we succeeded in taking the reserved lock, unlock it to restore
      ** the original state */
      lrc = _AFPFSSetLock(context->dbPath, pFile, RESERVED_BYTE, 1, 0);
    } else {
      /* if we failed to get the lock then someone else must have it */
      reserved = 1;
    }
    if( IS_LOCK_ERROR(lrc) ){
      rc=lrc;
    }

  ** acquiring an EXCLUSIVE lock.  For the SHARED lock, the PENDING will
  ** be released.
  */
  if( locktype==SHARED_LOCK 
      || (locktype==EXCLUSIVE_LOCK && pFile->locktype<PENDING_LOCK)
  ){
    int failed;
    failed = _AFPFSSetLock(context->dbPath, pFile, PENDING_BYTE, 1, 1);
    if (failed) {
      rc = failed;
      goto afp_end_lock;
    }
  }
  
  /* If control gets to this point, then actually go ahead and make
  ** operating system calls for the specified lock.
  */
  if( locktype==SHARED_LOCK ){
    int lk, lrc1, lrc2, lrc1Errno;
    
    /* Now get the read-lock SHARED_LOCK */
    /* note that the quality of the randomness doesn't matter that much */
    lk = random(); 
    context->sharedByte = (lk & 0x7fffffff)%(SHARED_SIZE - 1);
    lrc1 = _AFPFSSetLock(context->dbPath, pFile, 
          SHARED_FIRST+context->sharedByte, 1, 1);
    if( IS_LOCK_ERROR(lrc1) ){
      lrc1Errno = pFile->lastErrno;
    }
    /* Drop the temporary PENDING lock */
    lrc2 = _AFPFSSetLock(context->dbPath, pFile, PENDING_BYTE, 1, 0);
    
    if( IS_LOCK_ERROR(lrc1) ) {
      pFile->lastErrno = lrc1Errno;
      rc = lrc1;
      goto afp_end_lock;
    } else if( IS_LOCK_ERROR(lrc2) ){
      rc = lrc2;
      goto afp_end_lock;
    } else if( lrc1 != SQLITE_OK ) {
      rc = lrc1;
    } else {
      pFile->locktype = SHARED_LOCK;
      pFile->pOpen->nLock++;
    }
  }else{
    /* The request was for a RESERVED or EXCLUSIVE lock.  It is
    ** assumed that there is a SHARED or greater lock on the file
    ** already.
    */
    int failed = 0;
    assert( 0!=pFile->locktype );
    if (locktype >= RESERVED_LOCK && pFile->locktype < RESERVED_LOCK) {
        /* Acquire a RESERVED lock */
        failed = _AFPFSSetLock(context->dbPath, pFile, RESERVED_BYTE, 1,1);
    }
    if (!failed && locktype == EXCLUSIVE_LOCK) {
      /* Acquire an EXCLUSIVE lock */
        
      /* Remove the shared lock before trying the range.  we'll need to 
      ** reestablish the shared lock if we can't get the  afpUnlock
      */
      if( !(failed = _AFPFSSetLock(context->dbPath, pFile, SHARED_FIRST +
                         context->sharedByte, 1, 0)) ){
        int failed2 = SQLITE_OK;
        /* now attemmpt to get the exclusive lock range */
        failed = _AFPFSSetLock(context->dbPath, pFile, SHARED_FIRST, 
                               SHARED_SIZE, 1);
        if( failed && (failed2 = _AFPFSSetLock(context->dbPath, pFile, 
                       SHARED_FIRST + context->sharedByte, 1, 1)) ){
          /* Can't reestablish the shared lock.  Sqlite can't deal, this is
          ** a critical I/O error
          */
          rc = ((failed & SQLITE_IOERR) == SQLITE_IOERR) ? failed2 : 
               SQLITE_IOERR_LOCK;
          goto afp_end_lock;
        } 
      }else{
        rc = failed; 
      }
    }
    if( failed ){
      rc = failed;
    }
  }

**
** If the locking level of the file descriptor is already at or below
** the requested locking level, this routine is a no-op.
*/
static int afpUnlock(sqlite3_file *id, int locktype) {
  int rc = SQLITE_OK;
  unixFile *pFile = (unixFile*)id;
  afpLockingContext *pCtx = (afpLockingContext *) pFile->lockingContext;

  assert( pFile );
  OSTRACE5("UNLOCK  %d %d was %d pid=%d\n", pFile->h, locktype,
         pFile->locktype, getpid());

  assert( locktype<=SHARED_LOCK );
  if( pFile->locktype<=locktype ){
    return SQLITE_OK;
  }
  if( CHECK_THREADID(pFile) ){
    return SQLITE_MISUSE;
  }
  enterMutex();

  if( pFile->locktype>SHARED_LOCK ){

    

    if( pFile->locktype==EXCLUSIVE_LOCK ){
      rc = _AFPFSSetLock(pCtx->dbPath, pFile, SHARED_FIRST, SHARED_SIZE, 0);
      if( rc==SQLITE_OK && locktype==SHARED_LOCK ){

        /* only re-establish the shared lock if necessary */
        int sharedLockByte = SHARED_FIRST+pCtx->sharedByte;
        rc = _AFPFSSetLock(pCtx->dbPath, pFile, sharedLockByte, 1, 1);

      }
    }
    if( rc==SQLITE_OK && pFile->locktype>=PENDING_LOCK ){
      rc = _AFPFSSetLock(pCtx->dbPath, pFile, PENDING_BYTE, 1, 0);
    } 

    if( rc==SQLITE_OK && pFile->locktype>=RESERVED_LOCK ){
      rc = _AFPFSSetLock(pCtx->dbPath, pFile, RESERVED_BYTE, 1, 0);
    }
  }else if( locktype==NO_LOCK ){
    /* clear the shared lock */
    int sharedLockByte = SHARED_FIRST+pCtx->sharedByte;
    rc = _AFPFSSetLock(pCtx->dbPath, pFile, sharedLockByte, 1, 0);
  }

  if( rc==SQLITE_OK ){
    if( locktype==NO_LOCK ){
      struct openCnt *pOpen = pFile->pOpen;
      pOpen->nLock--;
      assert( pOpen->nLock>=0 );
      if( pOpen->nLock==0 && pOpen->nPending>0 ){
        int i;
        for(i=0; i<pOpen->nPending; i++){
          if( pOpen->aPending[i] < 0 ) continue;
          if( close(pOpen->aPending[i]) ){
            pFile->lastErrno = errno;
            rc = SQLITE_IOERR_CLOSE;
          }else{
            pOpen->aPending[i] = -1;
          }
        }
        if( rc==SQLITE_OK ){



          sqlite3_free(pOpen->aPending);
          pOpen->nPending = 0;
          pOpen->aPending = 0;
        }
      }
    }





  }


end_afpunlock:
  leaveMutex();
  if( rc==SQLITE_OK ) pFile->locktype = locktype;
  return rc;
}

/*
** Close a file & cleanup AFP specific locking context 
*/
static int afpClose(sqlite3_file *id) {
  if( id ){
    unixFile *pFile = (unixFile*)id;
    afpUnlock(id, NO_LOCK);
    enterMutex();
    if( pFile->pOpen && pFile->pOpen->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 pOpen->aPending.  It will be automatically closed when
       ** the last lock is cleared.
       */
      int *aNew;
      struct openCnt *pOpen = pFile->pOpen;
      aNew = sqlite3_realloc(pOpen->aPending, (pOpen->nPending+1)*sizeof(int) );
      if( aNew==0 ){
        /* If a malloc fails, just leak the file descriptor */
      }else{
        pOpen->aPending = aNew;
        pOpen->aPending[pOpen->nPending] = pFile->h;
        pOpen->nPending++;
        pFile->h = -1;
      }
    }
    releaseOpenCnt(pFile->pOpen);
    sqlite3_free(pFile->lockingContext);
    closeUnixFile(id);
    leaveMutex();
  }
  return SQLITE_OK;
}


#pragma mark flock() style locking

/*
** The flockLockingContext is not used

        pFile->lastErrno = tErrno;
        rc = lrc;
      }
    }
  }
  OSTRACE4("TEST WR-LOCK %d %d %d\n", pFile->h, rc, reserved);

#ifdef SQLITE_IGNORE_FLOCK_LOCK_ERRORS
  if( (rc & SQLITE_IOERR) == SQLITE_IOERR ){
    rc = SQLITE_OK;
    reserved=1;
  }
#endif /* SQLITE_IGNORE_FLOCK_LOCK_ERRORS */
  *pResOut = reserved;
  return rc;
}

static int flockLock(sqlite3_file *id, int locktype) {
  int rc = SQLITE_OK;
  int lrc;
  unixFile *pFile = (unixFile*)id;

  assert( pFile );

  /* if we already have a lock, it is exclusive.  
  ** Just adjust level and punt on outta here. */
  if (pFile->locktype > NO_LOCK) {

    }
  } else {
    /* got it, set the type and return ok */
    pFile->locktype = locktype;
  }
  OSTRACE4("LOCK    %d %s %s\n", pFile->h, locktypeName(locktype), 
           rc==SQLITE_OK ? "ok" : "failed");
#ifdef SQLITE_IGNORE_FLOCK_LOCK_ERRORS
  if( (rc & SQLITE_IOERR) == SQLITE_IOERR ){
    rc = SQLITE_BUSY;
  }
#endif /* SQLITE_IGNORE_FLOCK_LOCK_ERRORS */
  return rc;
}

static int flockUnlock(sqlite3_file *id, int locktype) {
  unixFile *pFile = (unixFile*)id;
  
  assert( pFile );

  int rc = flock(pFile->h, LOCK_UN);
  if (rc) {
    int r, tErrno = errno;
    r = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_UNLOCK);
    if( IS_LOCK_ERROR(r) ){
      pFile->lastErrno = tErrno;
    }
#ifdef SQLITE_IGNORE_FLOCK_LOCK_ERRORS
    if( (r & SQLITE_IOERR) == SQLITE_IOERR ){
      r = SQLITE_BUSY;
    }
#endif /* SQLITE_IGNORE_FLOCK_LOCK_ERRORS */
    
    return r;
  } else {
    pFile->locktype = NO_LOCK;
    return SQLITE_OK;
  }
}

/*
** Close a file.
*/
static int flockClose(sqlite3_file *id) {
  if( id ){
    flockUnlock(id, NO_LOCK);
  }
  return closeUnixFile(id);
}

#endif /* !IS_VXWORKS */

#pragma mark Old-School .lock file based locking
#define DOTLOCK_SUFFIX ".lock"

/* Dotlock-style reserved lock checking following the behavior of 
** unixCheckReservedLock, see the unixCheckReservedLock function comments */
static int dotlockCheckReservedLock(sqlite3_file *id, int *pResOut) {
  int rc = SQLITE_OK;
  int reserved = 0;
  unixFile *pFile = (unixFile*)id;

    /* failed to open/create the file, someone else may have stolen the lock */
    int tErrno = errno;
    if( EEXIST == tErrno ){
      rc = SQLITE_BUSY;
    } else {
      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
      if( IS_LOCK_ERROR(rc) ){
        pFile->lastErrno = tErrno;
      }
    }
    goto dotlock_end_lock;
  } 
  if( close(fd) ){
    pFile->lastErrno = errno;
    rc = SQLITE_IOERR_CLOSE;
  }
  
  /* got it, set the type and return ok */
  pFile->locktype = locktype;

 dotlock_end_lock:
  return rc;
}

    if( sem_trywait(pSem)==-1 ){
      int tErrno = errno;
      if( EAGAIN != tErrno ){
        rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_CHECKRESERVEDLOCK);
        pFile->lastErrno = tErrno;
      } else {
        /* someone else has the lock when we are in NO_LOCK */
        reserved = (pFile->locktype < SHARED_LOCK);
      }
    }else{
      /* we could have it if we want it */
      sem_post(pSem);
    }
  }
  OSTRACE4("TEST WR-LOCK %d %d %d\n", pFile->h, rc, reserved);

    closeUnixFile(id);
    leaveMutex();
  }
  return SQLITE_OK;
}

#endif /* IS_VXWORKS */

#pragma mark Proxy locking support

static int proxyCheckReservedLock(sqlite3_file *id, int *pResOut) {
  unixFile *pFile = (unixFile*)id;
  int rc = takeConch(pFile);
  if( rc==SQLITE_OK ){
    proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
    unixFile *proxy = pCtx->lockProxy;
    return proxy->pMethod->xCheckReservedLock((sqlite3_file*)proxy, pResOut);
  }
  return rc;
}

static int proxyLock(sqlite3_file *id, int locktype) {
  unixFile *pFile = (unixFile*)id;
  int rc = takeConch(pFile);
  if( rc==SQLITE_OK ){
    proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
    unixFile *proxy = pCtx->lockProxy;
    rc = proxy->pMethod->xLock((sqlite3_file*)proxy, locktype);
    pFile->locktype = proxy->locktype;
  }
  return rc;
}

static int proxyUnlock(sqlite3_file *id, int locktype) {
  unixFile *pFile = (unixFile*)id;
  int rc = takeConch(pFile);
  if( rc==SQLITE_OK ){
    proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
    unixFile *proxy = pCtx->lockProxy;
    rc = proxy->pMethod->xUnlock((sqlite3_file*)proxy, locktype);
    pFile->locktype = proxy->locktype;
  }
  return rc;
}

/*
 ** Close a file.
 */
static int proxyClose(sqlite3_file *id) {
  if( id ){
    unixFile *pFile = (unixFile*)id;
    proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
    unixFile *lockProxy = pCtx->lockProxy;
    unixFile *conchFile = pCtx->conchFile;
    int rc = SQLITE_OK;
    
    if( lockProxy ){
      rc = lockProxy->pMethod->xUnlock((sqlite3_file*)lockProxy, NO_LOCK);
      if( rc ) return rc;
      rc = lockProxy->pMethod->xClose((sqlite3_file*)lockProxy);
      if( rc ) return rc;
      sqlite3_free(lockProxy);
    }
    if( conchFile ){
      if( pCtx->conchHeld ){
        rc = releaseConch(pFile);
        if( rc ) return rc;
      }
      rc = conchFile->pMethod->xClose((sqlite3_file*)conchFile);
      if( rc ) return rc;
      sqlite3_free(conchFile);
    }
    sqlite3_free(pCtx->lockProxyPath);
    sqlite3_free(pCtx->conchFilePath);
    sqlite3_free(pCtx->dbPath);
    /* restore the original locking context and pMethod then close it */
    pFile->lockingContext = pCtx->oldLockingContext;
    pFile->pMethod = pCtx->pOldMethod;
    sqlite3_free(pCtx);
    return pFile->pMethod->xClose(id);
  }
  return SQLITE_OK;
}

/* HOSTIDLEN and CONCHLEN both include space for the string 
** terminating nul 
*/
#define HOSTIDLEN         128
#define CONCHLEN          (MAXPATHLEN+HOSTIDLEN+1)
#ifndef HOSTIDPATH
# define HOSTIDPATH       "/Library/Caches/.com.apple.sqliteConchHostId"
#endif

/* basically a copy of unixRandomness with different
** test behavior built in */
static int genHostID(char *pHostID){
  int pid, fd, i, len;
  unsigned char *key = (unsigned char *)pHostID;
  
  memset(key, 0, HOSTIDLEN);
  len = 0;
  fd = open("/dev/urandom", O_RDONLY);
  if( fd>=0 ){
    len = read(fd, key, HOSTIDLEN);
    close(fd); /* silently leak the fd if it fails */
  }
  if( len < HOSTIDLEN ){
    time_t t;
    time(&t);
    memcpy(key, &t, sizeof(t));
    pid = getpid();
    memcpy(&key[sizeof(t)], &pid, sizeof(pid));
  }
  
#ifdef MAKE_PRETTY_HOSTID
  /* filter the bytes into printable ascii characters and NUL terminate */
  key[(HOSTIDLEN-1)] = 0x00;
  for( i=0; i<(HOSTIDLEN-1); i++ ){
    unsigned char pa = key[i]&0x7F;
    if( pa<0x20 ){
      key[i] = (key[i]&0x80 == 0x80) ? pa+0x40 : pa+0x20;
    }else if( pa==0x7F ){
      key[i] = (key[i]&0x80 == 0x80) ? pa=0x20 : pa+0x7E;
    }
  }
#endif
  return SQLITE_OK;
}

#ifdef SQLITE_TEST
/* simulate multiple hosts by creating unique hostid file paths */
int sqlite3_hostid_num = 0;
#endif

/* writes the host id path to path, path should be an pre-allocated buffer
** with enough space for a path */
static int getHostIDPath(char *path, size_t len){
  strlcpy(path, HOSTIDPATH, len);
#ifdef SQLITE_TEST
  if( sqlite3_hostid_num>0 ){
    char suffix[2] = "1";
    suffix[0] = suffix[0] + sqlite3_hostid_num;
    strlcat(path, suffix, len);
  }
#endif
  OSTRACE3("GETHOSTIDPATH  %s pid=%d\n", path, getpid());
}

/* get the host ID from a sqlite hostid file stored in the 
** user-specific tmp directory, create the ID if it's not there already 
*/
static int getHostID(char *pHostID, int *pError){
  int fd;
  char path[MAXPATHLEN]; 
  size_t len;
	int rc=SQLITE_OK;

  getHostIDPath(path, MAXPATHLEN);
  /* try to create the host ID file, if it already exists read the contents */
  fd = open(path, O_CREAT|O_WRONLY|O_EXCL, 0644);
  if( fd<0 ){
    int err=errno;
		
    if( err!=EEXIST ){
#ifdef SQLITE_PROXY_DEBUG /* set the sqlite error message instead */
      fprintf(stderr, "sqlite error creating host ID file %s: %s\n", path, strerror(err));
#endif
      return SQLITE_PERM;
    }
    /* couldn't create the file, read it instead */
    fd = open(path, O_RDONLY|O_EXCL);
    if( fd<0 ){
      int err = errno;
#ifdef SQLITE_PROXY_DEBUG /* set the sqlite error message instead */
      fprintf(stderr, "sqlite error opening host ID file %s: %s\n", path, strerror(err));
#endif
      return SQLITE_PERM;
    }
    len = pread(fd, pHostID, HOSTIDLEN, 0);
		if( len<0 ){
			*pError = errno;
			rc = SQLITE_IOERR_READ;
		}else if( len<HOSTIDLEN ){
			*pError = 0;
			rc = SQLITE_IOERR_SHORT_READ;
		}
    close(fd); /* silently leak the fd if it fails */
    OSTRACE3("GETHOSTID  read %s pid=%d\n", pHostID, getpid());
    return rc;
  }else{
    int i;
    /* we're creating the host ID file (use a random string of bytes) */
    genHostID(pHostID);
    len = pwrite(fd, pHostID, HOSTIDLEN, 0);
		if( len<0 ){
			*pError = errno;
			rc = SQLITE_IOERR_WRITE;
		}else if( len<HOSTIDLEN ){
			*pError = 0;
			rc = SQLITE_IOERR_WRITE;
		}
    close(fd); /* silently leak the fd if it fails */
    OSTRACE3("GETHOSTID  wrote %s pid=%d\n", pHostID, getpid());
    return rc;
  }
}

/* takes the conch by taking a shared lock and read the contents conch, if 
** lockPath is non-NULL, the host ID and lock file path must match.  A NULL 
** lockPath means that the lockPath in the conch file will be used if the 
** host IDs match, or a new lock path will be generated automatically 
** and written to the conch file.
*/
static int takeConch(unixFile *pFile){
  proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext; 
  
  if( pCtx->conchHeld>0 ){
    return SQLITE_OK;
  }else{
    unixFile *conchFile = pCtx->conchFile;
    char testValue[CONCHLEN];
    char conchValue[CONCHLEN];
    char lockPath[MAXPATHLEN];
    char *tLockPath = NULL;
    int rc = SQLITE_OK;
    int readRc = SQLITE_OK;
    int syncPerms = 0;

    OSTRACE4("TAKECONCH  %d for %s pid=%d\n", conchFile->h,
             (pCtx->lockProxyPath ? pCtx->lockProxyPath : ":auto:"), getpid());

    rc = conchFile->pMethod->xLock((sqlite3_file*)conchFile, SHARED_LOCK);
    if( rc==SQLITE_OK ){
			int pError = 0;
      memset(testValue, 0, CONCHLEN); // conch is fixed size
      rc = getHostID(testValue, &pError);
			if( rc&SQLITE_IOERR==SQLITE_IOERR ){
				pFile->lastErrno = pError;
			}
      if( pCtx->lockProxyPath ){
        strlcpy(&testValue[HOSTIDLEN], pCtx->lockProxyPath, MAXPATHLEN);
      }
    }
    if( rc!=SQLITE_OK ){
      goto end_takeconch;
    }
    
    readRc = unixRead((sqlite3_file *)conchFile, conchValue, CONCHLEN, 0);
    if( readRc!=SQLITE_IOERR_SHORT_READ ){
      int match = 0;
      if( readRc!=SQLITE_OK ){
				if( rc&SQLITE_IOERR==SQLITE_IOERR ){
					pFile->lastErrno = conchFile->lastErrno;
				}
        rc = readRc;
        goto end_takeconch;
      }
      /* if the conch has data compare the contents */
      if( !pCtx->lockProxyPath ){
        /* for auto-named local lock file, just check the host ID and we'll
         ** use the local lock file path that's already in there */
        if( !memcmp(testValue, conchValue, HOSTIDLEN) ){
          tLockPath = (char *)&conchValue[HOSTIDLEN];
          goto end_takeconch;
        }
      }else{
        /* we've got the conch if conchValue matches our path and host ID */
        if( !memcmp(testValue, conchValue, CONCHLEN) ){
          goto end_takeconch;
        }
      }
    }else{
      /* a short read means we're "creating" the conch (even though it could 
      ** have been user-intervention), if we acquire the exclusive lock,
      ** we'll try to match the current on-disk permissions of the database
      */
      syncPerms = 1;
    }
    
    /* either conch was emtpy or didn't match */
    if( !pCtx->lockProxyPath ){
      getLockPath(pCtx->dbPath, lockPath, MAXPATHLEN);
      tLockPath = lockPath;
      strlcpy(&testValue[HOSTIDLEN], lockPath, MAXPATHLEN);
    }
    
    /* update conch with host and path (this will fail if other process
     ** has a shared lock already) */
    rc = conchFile->pMethod->xLock((sqlite3_file*)conchFile, EXCLUSIVE_LOCK);
    if( rc==SQLITE_OK ){
      rc = unixWrite((sqlite3_file *)conchFile, testValue, CONCHLEN, 0);
      if( rc==SQLITE_OK && syncPerms ){
        struct stat buf;
        int err = fstat(pFile->h, &buf);
        if( err==0 ){
          mode_t mode = buf.st_mode & 0100666;
          /* try to match the database file permissions, ignore failure */
#ifndef SQLITE_PROXY_DEBUG
          fchmod(conchFile->h, buf.st_mode);
#else
          if( fchmod(conchFile->h, buf.st_mode)!=0 ){
            int code = errno;
            fprintf(stderr, "fchmod %o FAILED with %d %s\n",buf.st_mode, code, strerror(code));
          } else {
            fprintf(stderr, "fchmod %o SUCCEDED\n",buf.st_mode);
          }
        }else{
          int code = errno;
          fprintf(stderr, "STAT FAILED[%d] with %d %s\n", err, code, strerror(code));
#endif
        }
      }
    }
    conchFile->pMethod->xUnlock((sqlite3_file*)conchFile, SHARED_LOCK);
  
end_takeconch:
    OSTRACE2("TRANSPROXY: CLOSE  %d\n", pFile->h);
    if( rc==SQLITE_OK && pFile->oflags ){
      if( pFile->h>=0 ){
#ifdef STRICT_CLOSE_ERROR
        if( close(pFile->h) ){
          pFile->lastErrno = errno;
          return SQLITE_IOERR_CLOSE;
        }
#else
        close(pFile->h); /* silently leak fd if fail */
#endif
      }
      pFile->h = -1;
      int fd = open(pCtx->dbPath, pFile->oflags, SQLITE_DEFAULT_FILE_PERMISSIONS);
      OSTRACE2("TRANSPROXY: OPEN  %d\n", fd);
      if( fd>=0 ){
        pFile->h = fd;
      }else{
        rc=SQLITE_CANTOPEN; // SQLITE_BUSY? takeConch called during locking
      }
    }
    if( rc==SQLITE_OK && !pCtx->lockProxy ){
      char *path = tLockPath ? tLockPath : pCtx->lockProxyPath;
      // ACS: Need to make a copy of path sometimes
      rc = createProxyUnixFile(path, &pCtx->lockProxy);
    }
    if( rc==SQLITE_OK ){
      pCtx->conchHeld = 1;

      if( tLockPath ){
        pCtx->lockProxyPath = sqlite3DbStrDup(0, tLockPath);
        if( pCtx->lockProxy->pMethod == ioMethodForLockingStyle(LOCKING_STYLE_AFP) ){
          ((afpLockingContext *)pCtx->lockProxy->lockingContext)->dbPath = pCtx->lockProxyPath;
        }
      }
    } else {
      conchFile->pMethod->xUnlock((sqlite3_file*)conchFile, NO_LOCK);
    }
    OSTRACE3("TAKECONCH  %d %s\n", conchFile->h, rc==SQLITE_OK ? "ok" : "failed");
    return rc;
  }
}
  
static int releaseConch(unixFile *pFile){
  proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
  int rc;
  unixFile *conchFile = pCtx->conchFile;

  OSTRACE4("RELEASECONCH  %d for %s pid=%d\n", conchFile->h,
           (pCtx->lockProxyPath ? pCtx->lockProxyPath : ":auto:"), 
           getpid());
  pCtx->conchHeld = 0;
  rc = conchFile->pMethod->xUnlock((sqlite3_file*)conchFile, NO_LOCK);
  OSTRACE3("RELEASECONCH  %d %s\n", conchFile->h,
           (rc==SQLITE_OK ? "ok" : "failed"));
  return rc;
}

static int getConchPathFromDBPath(char *dbPath, char **pConchPath){
  int i;
  int len = strlen(dbPath);
  char *conchPath;
  
  conchPath = (char *)sqlite3_malloc(len + 8);
  if( conchPath==0 ){
    return SQLITE_NOMEM;
  }
  strlcpy(conchPath, dbPath, len+1);
  
  /* now insert a "." before the last / character */
  for( i=(len-1); i>=0; i-- ){
    if( conchPath[i]=='/' ){
      i++;
      break;
    }
  }
  conchPath[i]='.';
  while ( i<len ){
    conchPath[i+1]=dbPath[i];
    i++;
  }
  conchPath[i+1]='\0';
  strlcat(conchPath, "-conch", len + 8);
  *pConchPath = conchPath;
  return SQLITE_OK;
}

static int getLockPath(const char *dbPath, char *lPath, size_t maxLen){
  int len;
  int dbLen;
  int i;

#ifdef LOCKPROXYDIR
  len = strlcpy(lPath, LOCKPROXYDIR, maxLen);
#else
# ifdef _CS_DARWIN_USER_TEMP_DIR
  {
    char utdir[MAXPATHLEN];
    
    confstr(_CS_DARWIN_USER_TEMP_DIR, lPath, maxLen);
    len = strlcat(lPath, "sqliteplocks", maxLen);
    if( mkdir(lPath, SQLITE_DEFAULT_PROXYDIR_PERMISSIONS) ){
      /* if mkdir fails, handle as lock file creation failure */
      int err = errno;
#  ifdef SQLITE_DEBUG
      if( err!=EEXIST ){
        fprintf(stderr, "getLockPath: mkdir(%s,0%o) error %d %s\n", lPath,
                SQLITE_DEFAULT_PROXYDIR_PERMISSIONS, err, strerror(err));
      }
#  endif
    }else{
      OSTRACE3("GETLOCKPATH  mkdir %s pid=%d\n", lPath, getpid());
    }
    
  }
# else
  len = strlcpy(lPath, "/tmp/", maxLen);
# endif
#endif

  if( lPath[len-1]!='/' ){
    len = strlcat(lPath, "/", maxLen);
  }
  
  /* transform the db path to a unique cache name */
  dbLen = strlen(dbPath);
  for( i=0; i<dbLen && (i+len+7)<maxLen; i++){
    char c = dbPath[i];
    lPath[i+len] = (c=='/')?'_':c;
  }
  lPath[i+len]='\0';
  strlcat(lPath, ":auto:", maxLen);
  return SQLITE_OK;
}

/* Takes a fully configured proxy locking-style unix file and switches
** the local lock file path 
*/
static int switchLockProxyPath(unixFile *pFile, const char *path) {
  proxyLockingContext *pCtx = (proxyLockingContext*)pFile->lockingContext;
  char *oldPath = pCtx->lockProxyPath;
  int taken = 0;
  int rc = SQLITE_OK;

  if( pFile->locktype!=NO_LOCK ){
    return SQLITE_BUSY;
  }  

  /* nothing to do if the path is NULL, :auto: or matches the existing path */
  if( !path || path[0]=='\0' || !strcmp(path, ":auto:") ||
    (oldPath && !strncmp(oldPath, path, MAXPATHLEN)) ){
    return SQLITE_OK;
  }else{
    unixFile *lockProxy = pCtx->lockProxy;
    pCtx->lockProxy=NULL;
    pCtx->conchHeld = 0;
    if( lockProxy!=NULL ){
      rc=lockProxy->pMethod->xClose((sqlite3_file *)lockProxy);
      if( rc ) return rc;
      sqlite3_free(lockProxy);
    }
    sqlite3_free(oldPath);
    pCtx->lockProxyPath = sqlite3DbStrDup(0, path);
  }
  
  return rc;
}

/*
** Takes an already filled in unix file and alters it so all file locking 
** will be performed on the local proxy lock file.  The following fields
** are preserved in the locking context so that they can be restored and 
** the unix structure properly cleaned up at close time:
**  ->lockingContext
**  ->pMethod
*/
static int transformUnixFileForLockProxy(unixFile *pFile, const char *path) {
  proxyLockingContext *pCtx;
  char dbPath[MAXPATHLEN];
  char *lockPath=NULL;
  int rc = SQLITE_OK;
  
  if( pFile->locktype!=NO_LOCK ){
    return SQLITE_BUSY;
  }
  getDbPathForUnixFile(pFile, dbPath);
  if( !path || path[0]=='\0' || !strcmp(path, ":auto:") ){
    lockPath=NULL;
  }else{
    lockPath=(char *)path;
  }
  
  OSTRACE4("TRANSPROXY  %d for %s pid=%d\n", pFile->h,
           (lockPath ? lockPath : ":auto:"), getpid());

  pCtx = sqlite3_malloc( sizeof(*pCtx) );
  if( pCtx==0 ){
    return SQLITE_NOMEM;
  }
  memset(pCtx, 0, sizeof(*pCtx));

  rc = getConchPathFromDBPath(dbPath, &pCtx->conchFilePath);
  if( rc==SQLITE_OK ){
    rc = createProxyUnixFile(pCtx->conchFilePath, &pCtx->conchFile);
  }  
  if( rc==SQLITE_OK && lockPath ){
    pCtx->lockProxyPath = sqlite3DbStrDup(0, lockPath);
  }

end_transform_file:
  if( rc==SQLITE_OK ){
    /* all memory is allocated, proxys are created and assigned, 
    ** switch the locking context and pMethod then return.
    */
    pCtx->dbPath = sqlite3DbStrDup(0, dbPath);
    pCtx->oldLockingContext = pFile->lockingContext;
    pFile->lockingContext = pCtx;
    pCtx->pOldMethod = pFile->pMethod;
    pFile->pMethod = ioMethodForLockingStyle(LOCKING_STYLE_PROXY);
  }else{
    if( pCtx->conchFile ){ 
      rc = pCtx->conchFile->pMethod->xClose((sqlite3_file *)pCtx->conchFile);
      if( rc ) return rc;
      sqlite3_free(pCtx->conchFile);
    }
    sqlite3_free(pCtx->conchFilePath); 
    sqlite3_free(pCtx);
  }
  OSTRACE3("TRANSPROXY  %d %s\n", pFile->h,
           (rc==SQLITE_OK ? "ok" : "failed"));
  return rc;
} 

static int createProxyUnixFile(const char *path, unixFile **ppFile) {
  int fd;
  int dirfd = -1;
  unixFile *pNew;
  int rc = SQLITE_OK;

  fd = open(path, O_RDWR | O_CREAT, SQLITE_DEFAULT_FILE_PERMISSIONS);
  if( fd<0 ){
    return SQLITE_CANTOPEN;
  }
  
  pNew = (unixFile *)sqlite3_malloc(sizeof(unixFile));
  if( pNew==NULL ){
    rc = SQLITE_NOMEM;
    goto end_create_proxy;
  }
  memset(pNew, 0, sizeof(unixFile));
  
  rc = fillInUnixFile(NULL, fd, dirfd, (sqlite3_file*)pNew, path, 0, 0);
  if( rc==SQLITE_OK ){
    *ppFile = pNew;
    return SQLITE_OK;
  }
end_create_proxy:    
  close(fd); /* silently leak fd if error, we're already in error */
  sqlite3_free(pNew);
  return rc;
}


#endif /* SQLITE_ENABLE_LOCKING_STYLE */

/*
** The nolockLockingContext is void
*/
typedef void nolockLockingContext;

*/
static int unixFileControl(sqlite3_file *id, int op, void *pArg){
  switch( op ){
    case SQLITE_FCNTL_LOCKSTATE: {
      *(int*)pArg = ((unixFile*)id)->locktype;
      return SQLITE_OK;
    }
    case SQLITE_GET_LOCKPROXYFILE: {
#if SQLITE_ENABLE_LOCKING_STYLE
      unixFile *pFile = (unixFile*)id;
      if( pFile->pMethod == ioMethodForLockingStyle(LOCKING_STYLE_PROXY) ){
        proxyLockingContext *pCtx = (proxyLockingContext*)pFile->lockingContext;
        takeConch(pFile);
        if( pCtx->lockProxyPath ){
          *(const char **)pArg = pCtx->lockProxyPath;
        }else{
          *(const char **)pArg = ":auto: (not held)";
        }
      } else {
        *(const char **)pArg = NULL;
      }
#else
      *(void*)pArg = NULL;
#endif
      return SQLITE_OK;
    }
    case SQLITE_SET_LOCKPROXYFILE: {
#if SQLITE_ENABLE_LOCKING_STYLE
      unixFile *pFile = (unixFile*)id;
      int rc = SQLITE_OK;
      int isProxyStyle = (pFile->pMethod == ioMethodForLockingStyle(LOCKING_STYLE_PROXY));
      if( pArg==NULL || (const char *)pArg==0 ){
        if( isProxyStyle ){
          // turn off proxy locking - not supported
          rc = SQLITE_ERROR /*SQLITE_PROTOCOL? SQLITE_MISUSE?*/;
        }else{
          // turn off proxy locking - already off - NOOP
          rc = SQLITE_OK;
        }
      }else{
        const char *proxyPath = (const char *)pArg;
        if( isProxyStyle ){
          proxyLockingContext *pCtx = 
            (proxyLockingContext*)pFile->lockingContext;
          if( !strcmp(pArg, ":auto:") || (pCtx->lockProxyPath && !strncmp(pCtx->lockProxyPath, proxyPath, MAXPATHLEN)) ){
            rc = SQLITE_OK;
          }else{
            rc = switchLockProxyPath(pFile, proxyPath);
          }
        }else{
          // turn on proxy file locking 
          rc = transformUnixFileForLockProxy(pFile, proxyPath);
        }
      }
      return rc;
#else
      return SQLITE_ERROR /*SQLITE_PROTOCOL? SQLITE_MISUSE?*/;
#endif
    }
    case SQLITE_LAST_ERRNO: {
      *(int*)pArg = ((unixFile*)id)->lastErrno;
      return SQLITE_OK;
    }
      
  }
  return SQLITE_ERROR;
}

/*
** Return the sector size in bytes of the underlying block device for
** the specified file. This is almost always 512 bytes, but may be

** Return the device characteristics for the file. This is always 0 for unix.
*/
static int unixDeviceCharacteristics(sqlite3_file *NotUsed){
  UNUSED_PARAMETER(NotUsed);
  return 0;
}

#define IOMETHODS(xClose, xLock, xUnlock, xCheckReservedLock) {    \
1,                          /* iVersion */                           \
xClose,                     /* xClose */                             \
unixRead,                   /* xRead */                              \
unixWrite,                  /* xWrite */                             \
unixTruncate,               /* xTruncate */                          \
unixSync,                   /* xSync */                              \
unixFileSize,               /* xFileSize */                          \
xLock,                      /* xLock */                              \
xUnlock,                    /* xUnlock */                            \
xCheckReservedLock,         /* xCheckReservedLock */                 \
unixFileControl,            /* xFileControl */                       \
unixSectorSize,             /* xSectorSize */                        \
unixDeviceCharacteristics   /* xDeviceCapabilities */                \
}
static sqlite3_io_methods aIoMethod[] = {
IOMETHODS(unixClose, unixLock, unixUnlock, unixCheckReservedLock) 
,IOMETHODS(nolockClose, nolockLock, nolockUnlock, nolockCheckReservedLock)
#if SQLITE_ENABLE_LOCKING_STYLE
,IOMETHODS(dotlockClose, dotlockLock, dotlockUnlock,dotlockCheckReservedLock)
#if IS_VXWORKS
  ,IOMETHODS(nolockClose, nolockLock, nolockUnlock, nolockCheckReservedLock)
  ,IOMETHODS(nolockClose, nolockLock, nolockUnlock, nolockCheckReservedLock)
  ,IOMETHODS(namedsemClose, namedsemLock, namedsemUnlock, namedsemCheckReservedLock)
  ,IOMETHODS(nolockClose, nolockLock, nolockUnlock, nolockCheckReservedLock)
#else
  ,IOMETHODS(flockClose, flockLock, flockUnlock, flockCheckReservedLock)
  ,IOMETHODS(afpClose, afpLock, afpUnlock, afpCheckReservedLock)
  ,IOMETHODS(nolockClose, nolockLock, nolockUnlock, nolockCheckReservedLock)
  ,IOMETHODS(proxyClose, proxyLock, proxyUnlock, proxyCheckReservedLock)
#endif
#endif
/* The order of the IOMETHODS macros above is important.  It must be the
 ** same order as the LOCKING_STYLE numbers
 */
};

/*
** Initialize the contents of the unixFile structure pointed to by pId.
**
** When locking extensions are enabled, the filepath and locking style 
** are needed to determine the unixFile pMethod to use for locking operations.
** The locking-style specific lockingContext data structure is created 
** and assigned here also.

  int noLock,             /* Omit locking if true */
  int isDelete            /* Delete on close if true */
){
  int eLockingStyle;
  unixFile *pNew = (unixFile *)pId;
  int rc = SQLITE_OK;















































  assert( pNew->pLock==NULL );
  assert( pNew->pOpen==NULL );

  /* Parameter isDelete is only used on vxworks. Parameter pVfs is only
  ** used if ENABLE_LOCKING_STYLE is defined. Express this explicitly 
  ** here to prevent compiler warnings about unused parameters.
  */

  }
#endif

  if( noLock ){
    eLockingStyle = LOCKING_STYLE_NONE;
  }else{
    eLockingStyle = detectLockingStyle(pVfs, zFilename, h);
#if SQLITE_ENABLE_LOCKING_STYLE
    /* Cache zFilename in the locking context (AFP and dotlock override) for
    ** proxyLock activation is possible (remote proxy is based on db name)
    ** zFilename remains valid until file is closed, to support */
    pNew->lockingContext = (void*)zFilename;
#endif
  }

  /* Macro to define the static contents of an sqlite3_io_methods 
  ** structure for a unix backend file. Different locking methods
  ** require different functions for the xClose, xLock, xUnlock and
  ** xCheckReservedLock methods.
  */
  assert(LOCKING_STYLE_POSIX==1);
  assert(LOCKING_STYLE_NONE==2);
  assert(LOCKING_STYLE_DOTFILE==3);
  assert(LOCKING_STYLE_FLOCK==4);
  assert(LOCKING_STYLE_AFP==5);
  assert(LOCKING_STYLE_NAMEDSEM==6);
  assert(LOCKING_STYLE_PROXY==7);
    
  switch( eLockingStyle ){

    case LOCKING_STYLE_POSIX: {
      enterMutex();
#if IS_VXWORKS
      rc = findLockInfo(pNew, pNew->zRealpath, &pNew->pLock, &pNew->pOpen);
#else
      rc = findLockInfo(pNew, &pNew->pLock, &pNew->pOpen);
#endif
      leaveMutex();
      break;
    }

#if SQLITE_ENABLE_LOCKING_STYLE

#if !IS_VXWORKS
    case LOCKING_STYLE_AFP: {
      /* AFP locking uses the file path so it needs to be included in
      ** the afpLockingContext.
      */
      afpLockingContext *pCtx;
      pNew->lockingContext = pCtx = sqlite3_malloc( sizeof(*pCtx) );
      if( pCtx==0 ){
        rc = SQLITE_NOMEM;
      }else{
        /* NB: zFilename exists and remains valid until the file is closed
        ** according to requirement F11141.  So we do not need to make a
        ** copy of the filename. */
        pCtx->dbPath = zFilename;
        srandomdev();
        enterMutex();
        rc = findLockInfo(pNew, NULL, &pNew->pOpen);
        leaveMutex();        
      }
      break;
    }
#endif

    case LOCKING_STYLE_DOTFILE: {
      /* Dotfile locking uses the file path so it needs to be included in
      ** the dotlockLockingContext 
      */
      char *zLockFile;
      int nFilename;
      nFilename = strlen(zFilename) + 6;
      zLockFile = (char *)sqlite3_malloc(nFilename);
      if( zLockFile==0 ){
        rc = SQLITE_NOMEM;
      }else{
        sqlite3_snprintf(nFilename, zLockFile, "%s" DOTLOCK_SUFFIX, zFilename);
      }
      pNew->lockingContext = zLockFile;
      break;
    }

#if IS_VXWORKS
    case LOCKING_STYLE_NAMEDSEM: {
      /* Named semaphore locking uses the file path so it needs to be
       ** included in the namedsemLockingContext
       */
      enterMutex();
      rc = findLockInfo(h, pNew->zRealpath, &pNew->pLock, &pNew->pOpen);
      if( (rc==SQLITE_OK) && (pNew->pOpen->pSem==NULL) ){
        char *zSemName = pNew->pOpen->aSemName;
        int n;
        sqlite3_snprintf(MAX_PATHNAME, zSemName, "%s.sem", pNew->zRealpath);
        for( n=0; zSemName[n]; n++ )

  if( rc!=SQLITE_OK ){
    unlink(zFilename);
    isDelete = 0;
  }
  pNew->isDelete = isDelete;
#endif
  if( rc!=SQLITE_OK ){
    if( dirfd>=0 ) close(dirfd); /* silent leak if fail, already in error */
    close(h);
  }else{
    pNew->pMethod = &aIoMethod[eLockingStyle-1];
    OpenCounter(+1);
  }
  return rc;
}

#if SQLITE_ENABLE_LOCKING_STYLE
static sqlite3_io_methods *ioMethodForLockingStyle(int style){
  return &aIoMethod[style-1];
}

static int getDbPathForUnixFile(unixFile *pFile, char *dbPath){
  if( pFile->pMethod==ioMethodForLockingStyle(LOCKING_STYLE_AFP) ){
    /* afp style keeps a reference to the db path in the filePath field of the struct */
    strlcpy(dbPath, ((afpLockingContext *)pFile->lockingContext)->dbPath, MAXPATHLEN);
    return SQLITE_OK;
  }
  if( pFile->pMethod==ioMethodForLockingStyle(LOCKING_STYLE_DOTFILE) ){
    /* dot lock style uses the locking context to store the dot lock file path */
    int len = strlen((char *)pFile->lockingContext) - strlen(DOTLOCK_SUFFIX);
    strlcpy(dbPath, (char *)pFile->lockingContext, len + 1);
    return SQLITE_OK;
  }
  /* all other styles use the locking context to store the db file path */
  strlcpy(dbPath, (char *)pFile->lockingContext, MAXPATHLEN);
  return SQLITE_OK;
}
#endif

/*
** Open a file descriptor to the directory containing file zFilename.
** If successful, *pFd is set to the opened file descriptor and
** SQLITE_OK is returned. If an error occurs, either SQLITE_NOMEM
** or SQLITE_CANTOPEN is returned and *pFd is set to an undefined
** value.

/*
** Create a temporary file name in zBuf.  zBuf must be allocated
** by the calling process and must be big enough to hold at least
** pVfs->mxPathname bytes.
*/
static int getTempname(int nBuf, char *zBuf){
  static const char *azDirs[] = {
     0,
     0,
     "/var/tmp",
     "/usr/tmp",
     "/tmp",
     ".",
  };
  static const unsigned char zChars[] =

  /* It's odd to simulate an io-error here, but really this is just
  ** using the io-error infrastructure to test that SQLite handles this
  ** function failing. 
  */
  SimulateIOError( return SQLITE_IOERR );

  azDirs[0] = sqlite3_temp_directory;
  if (NULL == azDirs[1]) {
    azDirs[1] = getenv("TMPDIR");
  }
  
  for(i=0; i<sizeof(azDirs)/sizeof(azDirs[0]); i++){
    if( azDirs[i]==0 ) continue;
    if( stat(azDirs[i], &buf) ) continue;
    if( !S_ISDIR(buf.st_mode) ) continue;
    if( access(azDirs[i], 07) ) continue;
    zDir = azDirs[i];
    break;
  }

  int *pOutFlags
){
  int fd = 0;                    /* File descriptor returned by open() */
  int dirfd = -1;                /* Directory file descriptor */
  int oflags = 0;                /* Flags to pass to open() */
  int eType = flags&0xFFFFFF00;  /* Type of file to open */
  int noLock;                    /* True to omit locking primitives */
  int rc = SQLITE_OK;

  int isExclusive  = (flags & SQLITE_OPEN_EXCLUSIVE);
  int isDelete     = (flags & SQLITE_OPEN_DELETEONCLOSE);
  int isCreate     = (flags & SQLITE_OPEN_CREATE);
  int isReadonly   = (flags & SQLITE_OPEN_READONLY);
  int isReadWrite  = (flags & SQLITE_OPEN_READWRITE);

       || eType==SQLITE_OPEN_SUBJOURNAL   || eType==SQLITE_OPEN_MASTER_JOURNAL 
       || eType==SQLITE_OPEN_TRANSIENT_DB
  );

  memset(pFile, 0, sizeof(unixFile));

  if( !zName ){

    assert(isDelete && !isOpenDirectory);
    rc = getTempname(MAX_PATHNAME+1, zTmpname);
    if( rc!=SQLITE_OK ){
      return rc;
    }
    zName = zTmpname;
  }

  }
  if( isDelete ){
#if IS_VXWORKS
    zPath = zName;
#else
    unlink(zName);
#endif
  }else{
    ((unixFile *)pFile)->oflags = oflags;
  }
  if( pOutFlags ){
    *pOutFlags = flags;
  }

  assert(fd!=0);
  if( isOpenDirectory ){
    rc = openDirectory(zPath, &dirfd);
    if( rc!=SQLITE_OK ){
      close(fd); /* silently leak if fail, already in error */
      return rc;
    }
  }

#ifdef FD_CLOEXEC
  fcntl(fd, F_SETFD, fcntl(fd, F_GETFD, 0) | FD_CLOEXEC);
#endif

  noLock = eType!=SQLITE_OPEN_MAIN_DB;

#if SQLITE_PREFER_PROXY_LOCKING
  if( zPath!=NULL && !noLock ){
    char *envforce = getenv("SQLITE_FORCE_PROXY_LOCKING");
    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{
      struct statfs fsInfo;

      if( statfs(zPath, &fsInfo) == -1 ){
				((unixFile*)pFile)->lastErrno = errno;
        if( dirfd>=0 ) close(dirfd); /* silently leak if fail, in error */
        close(fd); /* silently leak if fail, in error */
        return SQLITE_IOERR_ACCESS;
      }
      useProxy = !(fsInfo.f_flags&MNT_LOCAL);
    }
    if( useProxy ){
      rc = fillInUnixFile(pVfs, fd, dirfd, pFile, zPath, noLock, isDelete);
      if( rc==SQLITE_OK ){
        rc = transformUnixFileForLockProxy((unixFile*)pFile, ":auto:");
      }
      return rc;
    }
  }
#endif
  
  return fillInUnixFile(pVfs, fd, dirfd, pFile, zPath, noLock, isDelete);
}

/*
** Delete the file at zPath. If the dirSync argument is true, fsync()
** the directory after deleting the file.
*/

      if( fsync(fd)==-1 )
#else
      if( fsync(fd) )
#endif
      {
        rc = SQLITE_IOERR_DIR_FSYNC;
      }
      if( close(fd)&&!rc ){
        rc = SQLITE_IOERR_DIR_CLOSE;
      }
    }
  }
#endif
  return rc;
}

/*

        }
      }
      zFull[j++] = zFull[i];
    }
    zFull[j] = 0;
  }
#endif
#endif /* #if IS_VXWORKS */
}


#ifndef SQLITE_OMIT_LOAD_EXTENSION
/*
** Interfaces for opening a shared library, finding entry points
** within the shared library, and closing the shared library.

  static sqlite3_vfs aVfs[] = {
    UNIXVFS("unix-posix",   LOCKING_STYLE_POSIX), 
    UNIXVFS("unix-afp",     LOCKING_STYLE_AFP), 
    UNIXVFS("unix-flock",   LOCKING_STYLE_FLOCK), 
    UNIXVFS("unix-dotfile", LOCKING_STYLE_DOTFILE), 
    UNIXVFS("unix-none",    LOCKING_STYLE_NONE),
    UNIXVFS("unix-namedsem",LOCKING_STYLE_NAMEDSEM),
    UNIXVFS("unix-proxy",   LOCKING_STYLE_PROXY)
  };
  for(i=0; i<(sizeof(aVfs)/sizeof(sqlite3_vfs)); i++){
    sqlite3_vfs_register(&aVfs[i], 0);
  }
#endif
#if IS_VXWORKS
  sqlite3HashInit(&nameHash, 1);

/*
** 2003 April 6
**
** 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 contains code used to implement the PRAGMA command.
**
** $Id: pragma.c,v 1.195 2008/11/21 00:10:35 aswift Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/* Ignore this whole file if pragmas are disabled
*/
#if !defined(SQLITE_OMIT_PRAGMA) && !defined(SQLITE_OMIT_PARSER)

      }else{
        sqlite3_temp_directory = 0;
      }
#endif /* SQLITE_OMIT_WSD */
    }
  }else

  /*
   **   PRAGMA [database.]lock_proxy_file
   **   PRAGMA [database.]lock_proxy_file = ":auto:"|"lock_file_path"
   **
   ** Return or set the value of the lock_proxy_file flag.  Changing
   ** the value sets a specific file to be used for database access locks.
   **
   */
  if( sqlite3StrICmp(zLeft, "lock_proxy_file")==0 ){
    if( !zRight ){
      Pager *pPager = sqlite3BtreePager(pDb->pBt);
      char *proxy_file_path = NULL;
      sqlite3_file *pFile = sqlite3PagerFile(pPager);
      sqlite3OsFileControl(pFile, SQLITE_GET_LOCKPROXYFILE, 
                           &proxy_file_path);
      
      if( proxy_file_path ){
        sqlite3VdbeSetNumCols(v, 1);
        sqlite3VdbeSetColName(v, 0, COLNAME_NAME, 
                              "lock_proxy_file", SQLITE_STATIC);
        sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, proxy_file_path, 0);
        sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
      }
    }else{
      Pager *pPager = sqlite3BtreePager(pDb->pBt);
      sqlite3_file *pFile = sqlite3PagerFile(pPager);
      int res;
      if( zRight[0] ){
        res=sqlite3OsFileControl(pFile, SQLITE_SET_LOCKPROXYFILE, 
                                     zRight);
      } else {
        res=sqlite3OsFileControl(pFile, SQLITE_SET_LOCKPROXYFILE, 
                                     NULL);
      }
      if( res!=SQLITE_OK ){
        sqlite3ErrorMsg(pParse, "failed to set lock proxy file");
        goto pragma_out;
      }
    }
  }else
      
    
  /*
  **   PRAGMA [database.]synchronous
  **   PRAGMA [database.]synchronous=OFF|ON|NORMAL|FULL
  **
  ** Return or set the local value of the synchronous flag.  Changing
  ** the local value does not make changes to the disk file and the
  ** default value will be restored the next time the database is

** on how SQLite interfaces are suppose to operate.
**
** The name of this file under configuration management is "sqlite.h.in".
** The makefile makes some minor changes to this file (such as inserting
** the version number) and changes its name to "sqlite3.h" as
** part of the build process.
**
** @(#) $Id: sqlite.h.in,v 1.416 2008/11/21 00:10:35 aswift Exp $
*/
#ifndef _SQLITE3_H_
#define _SQLITE3_H_
#include <stdarg.h>     /* Needed for the definition of va_list */

/*
** Make sure we can call this stuff from C++.

#define SQLITE_IOERR_RDLOCK            (SQLITE_IOERR | (9<<8))
#define SQLITE_IOERR_DELETE            (SQLITE_IOERR | (10<<8))
#define SQLITE_IOERR_BLOCKED           (SQLITE_IOERR | (11<<8))
#define SQLITE_IOERR_NOMEM             (SQLITE_IOERR | (12<<8))
#define SQLITE_IOERR_ACCESS            (SQLITE_IOERR | (13<<8))
#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
#define SQLITE_IOERR_LOCK              (SQLITE_IOERR | (15<<8))
#define SQLITE_IOERR_CLOSE             (SQLITE_IOERR | (16<<8))
#define SQLITE_IOERR_DIR_CLOSE         (SQLITE_IOERR | (17<<8))

/*
** CAPI3REF: Flags For File Open Operations {H10230} <H11120> <H12700>
**
** These bit values are intended for use in the
** 3rd parameter to the [sqlite3_open_v2()] interface and
** in the 4th parameter to the xOpen method of the

** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
** into an integer that the pArg argument points to. This capability
** is used during testing and only needs to be supported when SQLITE_TEST
** is defined.
*/
#define SQLITE_FCNTL_LOCKSTATE        1
#define SQLITE_GET_LOCKPROXYFILE      2
#define SQLITE_SET_LOCKPROXYFILE      3
#define SQLITE_LAST_ERRNO             4

/*
** CAPI3REF: Mutex Handle {H17110} <S20130>
**
** 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

**    May you share freely, never taking more than you give.
**
*************************************************************************
** Code for testing all sorts of SQLite interfaces.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library.
**
** $Id: test1.c,v 1.330 2008/11/21 00:10:35 aswift Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include <stdlib.h>
#include <string.h>

/*

  assert( rc==SQLITE_ERROR );
  rc = sqlite3_file_control(db, "notadatabase", SQLITE_FCNTL_LOCKSTATE, &iArg);
  assert( rc==SQLITE_ERROR );
  rc = sqlite3_file_control(db, "main", -1, &iArg);
  assert( rc==SQLITE_ERROR );
  rc = sqlite3_file_control(db, "temp", -1, &iArg);
  assert( rc==SQLITE_ERROR );

  return TCL_OK;
}


/*
** tclcmd:   file_control_lasterrno_test DB
**
** This TCL command runs the sqlite3_file_control interface and
** verifies correct operation of the SQLITE_LAST_ERRNO verb.
*/
static int file_control_lasterrno_test(
  ClientData clientData, /* Pointer to sqlite3_enable_XXX function */
  Tcl_Interp *interp,    /* The TCL interpreter that invoked this command */
  int objc,              /* Number of arguments */
  Tcl_Obj *CONST objv[]  /* Command arguments */
){
  int iArg = 0;
  sqlite3 *db;
  int rc;

  if( objc!=2 ){
    Tcl_AppendResult(interp, "wrong # args: should be \"",
        Tcl_GetStringFromObj(objv[0], 0), " DB", 0);
    return TCL_ERROR;
  }
  if( getDbPointer(interp, Tcl_GetString(objv[1]), &db) ) return TCL_ERROR;
  rc = sqlite3_file_control(db, NULL, SQLITE_LAST_ERRNO, &iArg);
  if( rc ) { Tcl_SetObjResult(interp, Tcl_NewIntObj(rc)); return TCL_ERROR; }
  if( iArg!=0 ) {
    Tcl_AppendResult(interp, "Unexpected non-zero errno: ",
                     Tcl_GetStringFromObj(Tcl_NewIntObj(iArg), 0), " ", 0);
    return TCL_ERROR;
  }
  return TCL_OK;  
}

/*
** tclcmd:   file_control_lockproxy_test DB
**
** This TCL command runs the sqlite3_file_control interface and
** verifies correct operation of the SQLITE_GET_LOCKPROXYFILE and
** SQLITE_SET_LOCKPROXYFILE verbs.
*/
static int file_control_lockproxy_test(
  ClientData clientData, /* Pointer to sqlite3_enable_XXX function */
  Tcl_Interp *interp,    /* The TCL interpreter that invoked this command */
  int objc,              /* Number of arguments */
  Tcl_Obj *CONST objv[]  /* Command arguments */
){
  int iArg = 0;
  sqlite3 *db;
  int rc;
  
  if( objc!=2 ){
    Tcl_AppendResult(interp, "wrong # args: should be \"",
                     Tcl_GetStringFromObj(objv[0], 0), " DB", 0);
    return TCL_ERROR;
  }
  if( getDbPointer(interp, Tcl_GetString(objv[1]), &db) ) return TCL_ERROR;
  
#ifdef SQLITE_ENABLE_LOCKING_STYLE
	{
    char *proxyPath = "test.proxy";
    char *testPath;
		rc = sqlite3_file_control(db, NULL, SQLITE_SET_LOCKPROXYFILE, proxyPath);
    if( rc ) { Tcl_SetObjResult(interp, Tcl_NewIntObj(rc)); return TCL_ERROR; }
    rc = sqlite3_file_control(db, NULL, SQLITE_GET_LOCKPROXYFILE, &testPath);
    if( strncmp(proxyPath,testPath,11) ) {
      Tcl_AppendResult(interp, "Lock proxy file did not match the previously assigned value", 0);
      return TCL_ERROR;
    }
    if( rc ) { Tcl_SetObjResult(interp, Tcl_NewIntObj(rc)); return TCL_ERROR; }
		rc = sqlite3_file_control(db, NULL, SQLITE_SET_LOCKPROXYFILE, proxyPath);
    if( rc ) { Tcl_SetObjResult(interp, Tcl_NewIntObj(rc)); return TCL_ERROR; }
  }
#endif
  return TCL_OK;  
}


/*
** tclcmd:   sqlite3_vfs_list
**
**   Return a tcl list containing the names of all registered vfs's.
*/
static int vfs_list(

*/
int Sqlitetest1_Init(Tcl_Interp *interp){
  extern int sqlite3_search_count;
  extern int sqlite3_interrupt_count;
  extern int sqlite3_open_file_count;
  extern int sqlite3_sort_count;
  extern int sqlite3_current_time;
  extern int sqlite3_hostid_num;
  extern int sqlite3_max_blobsize;
  extern int sqlite3BtreeSharedCacheReport(void*,
                                          Tcl_Interp*,int,Tcl_Obj*CONST*);
  static struct {
     char *zName;
     Tcl_CmdProc *xProc;
  } aCmd[] = {

     { "sqlite3_global_recover",     test_global_recover, 0   },
     { "working_64bit_int",          working_64bit_int,   0   },
     { "vfs_unlink_test",            vfs_unlink_test,     0   },
     { "vfs_initfail_test",          vfs_initfail_test,   0   },
     { "vfs_unregister_all",         vfs_unregister_all,  0   },
     { "vfs_reregister_all",         vfs_reregister_all,  0   },
     { "file_control_test",          file_control_test,   0   },
     { "file_control_lasterrno_test", file_control_lasterrno_test,  0   },
     { "file_control_lockproxy_test", file_control_lockproxy_test,  0   },
     { "sqlite3_vfs_list",           vfs_list,     0   },

     /* Functions from os.h */
#ifndef SQLITE_OMIT_UTF16
     { "add_test_collate",        test_collate, 0            },
     { "add_test_collate_needed", test_collate_needed, 0     },
     { "add_test_function",       test_function, 0           },

      (char*)&sqlite3_like_count, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite_interrupt_count", 
      (char*)&sqlite3_interrupt_count, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite_open_file_count", 
      (char*)&sqlite3_open_file_count, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite_current_time", 
      (char*)&sqlite3_current_time, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite_hostid_num", 
      (char*)&sqlite3_hostid_num, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite3_xferopt_count",
      (char*)&sqlite3_xferopt_count, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite3_pager_readdb_count",
      (char*)&sqlite3_pager_readdb_count, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite3_pager_writedb_count",
      (char*)&sqlite3_pager_writedb_count, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite3_pager_writej_count",

** 
** This file contains code used for testing the SQLite system.
** None of the code in this file goes into a deliverable build.
** 
** The focus of this file is providing the TCL testing layer
** access to compile-time constants.
**
** $Id: test_config.c,v 1.43 2008/11/21 00:10:35 aswift Exp $
*/

#include "sqliteLimit.h"

#include "sqliteInt.h"
#include "tcl.h"
#include <stdlib.h>

#ifdef SQLITE_OMIT_SCHEMA_VERSION_PRAGMAS
  Tcl_SetVar2(interp, "sqlite_options", "schema_version", "0", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "schema_version", "1", TCL_GLOBAL_ONLY);
#endif

#ifdef SQLITE_ENABLE_LOCKING_STYLE
    Tcl_SetVar2(interp, "sqlite_options", "lock_proxy_pragmas", "1", TCL_GLOBAL_ONLY);
#else
    Tcl_SetVar2(interp, "sqlite_options", "lock_proxy_pragmas", "0", TCL_GLOBAL_ONLY);
#endif
    
    
#ifdef SQLITE_OMIT_SHARED_CACHE
  Tcl_SetVar2(interp, "sqlite_options", "shared_cache", "0", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "shared_cache", "1", TCL_GLOBAL_ONLY);
#endif

#ifdef SQLITE_OMIT_SUBQUERY

#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library. The focus
# of these tests is exclusive access mode (i.e. the thing activated by 
# "PRAGMA locking_mode = EXCLUSIVE").
#
# $Id: exclusive.test,v 1.10 2008/11/21 00:10:35 aswift Exp $

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

ifcapable {!pager_pragmas} {
  finish_test
  return

# Close and reopen the database so that the temp database is no
# longer active.
#
db close
sqlite db test.db

# if we're using proxy locks, we use 3 filedescriptors for a db
# that is open but NOT writing changes, normally
# sqlite uses 1 (proxy locking adds the conch and the local lock)
set using_proxy 0
foreach {name value} [array get env SQLITE_FORCE_PROXY_LOCKING] {
  set using_proxy $value
}
set extrafds 0
if {$using_proxy!=0} {
  set extrafds 2
} 

do_test exclusive-5.0 {
  execsql {
    CREATE TABLE abc(a UNIQUE, b UNIQUE, c UNIQUE);
    BEGIN;
    INSERT INTO abc VALUES(1, 2, 3);
    INSERT INTO abc SELECT a+1, b+1, c+1 FROM abc;
  }
} {}
do_test exclusive-5.1 {
  # Three files are open: The db, journal and statement-journal.
  set sqlite_open_file_count
  expr $sqlite_open_file_count-$extrafds
} {3}
do_test exclusive-5.2 {
  execsql {
    COMMIT;
  }
  # One file open: the db.
  set sqlite_open_file_count
  expr $sqlite_open_file_count-$extrafds
} {1}
do_test exclusive-5.3 {
  execsql {
    PRAGMA locking_mode = exclusive;
    BEGIN;
    INSERT INTO abc VALUES(5, 6, 7);
  }
  # Two files open: the db and journal.
  set sqlite_open_file_count
  expr $sqlite_open_file_count-$extrafds
} {2}
do_test exclusive-5.4 {
  execsql {
    INSERT INTO abc SELECT a+10, b+10, c+10 FROM abc;
  }
  # Three files are open: The db, journal and statement-journal.
  set sqlite_open_file_count
  expr $sqlite_open_file_count-$extrafds
} {3}
do_test exclusive-5.5 {
  execsql {
    COMMIT;
  }
  # Three files are still open: The db, journal and statement-journal.
  set sqlite_open_file_count
  expr $sqlite_open_file_count-$extrafds
} {3}
do_test exclusive-5.6 {
  execsql {
    PRAGMA locking_mode = normal;
    SELECT * FROM abc;
  }
} {normal 1 2 3 2 3 4 5 6 7 11 12 13 12 13 14 15 16 17}
do_test exclusive-5.7 {
  # Just the db open.
  set sqlite_open_file_count
  expr $sqlite_open_file_count-$extrafds
} {1}

finish_test

# 2008 Jan 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.
#
#***********************************************************************
#
# $Id: filectrl.test,v 1.2 2008/11/21 00:10:35 aswift Exp $

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


do_test filectrl-1.1 {
  file_control_test db
} {}
do_test filectrl-1.2 {
  db eval {CREATE TEMP TABLE x(y);}
  file_control_test db
} {}
do_test filectrl-1.3 {
  db close
  sqlite3 db :memory:
  file_control_test db
} {}
do_test filectrl-1.4 {
  sqlite3 db test.db
  file_control_lasterrno_test db
} {}
do_test filectrl-1.5 {
  db close
  sqlite3 db test_control_lockproxy.db
  file_control_lockproxy_test db
} {}
db close
file delete -force .test_control_lockproxy.db-conch test.proxy
finish_test

# 2008 June 28
#
# 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 regression tests for SQLite library.  The
# focus of this script is database locks.
#
# $Id: lock5.test,v 1.4 2008/11/21 00:10:35 aswift Exp $

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

# This file is only run if using the unix backend compiled with the
# SQLITE_ENABLE_LOCKING_STYLE macro.
db close
if {[catch {sqlite3 db test.db -vfs unix-none} msg]} {
  finish_test
  return
}
db close

ifcapable lock_proxy_pragmas {
  set ::using_proxy 0
  foreach {name value} [array get env SQLITE_FORCE_PROXY_LOCKING] {
    set ::using_proxy $value
  }
  # Disable the proxy locking for these tests
  set env(SQLITE_FORCE_PROXY_LOCKING) "0"
}


do_test lock5-dotfile.1 {
  sqlite3 db test.db -vfs unix-dotfile
  execsql {
    BEGIN;
    CREATE TABLE t1(a, b);
  }

  } {1 2 3 4}
}

do_test lock5-flock.X {
  db close
  db2 close
} {}

ifcapable lock_proxy_pragmas {
  set env(SQLITE_FORCE_PROXY_LOCKING) $::using_proxy
}

finish_test

# 2008 October 6
#
# 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 regression tests for SQLite library.  The
# focus of this script is database locks.
#
# $Id: lock6.test,v 1.1 2008/11/21 00:10:35 aswift Exp $


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

# Launch another testfixture process to be controlled by this one. A
# channel name is returned that may be passed as the first argument to proc
# 'testfixture' to execute a command. The child testfixture process is shut
# down by closing the channel.
proc launch_testfixture {} {
  set prg [info nameofexec]
  if {$prg eq ""} {
    set prg [file join . testfixture]
  }
  set chan [open "|$prg tf_main2.tcl" r+]
  fconfigure $chan -buffering line
  return $chan
}

# Execute a command in a child testfixture process, connected by two-way
# channel $chan. Return the result of the command, or an error message.
proc testfixture {chan cmd} {
  puts $chan $cmd
  puts $chan OVER
  set r ""
  while { 1 } {
    set line [gets $chan]
    if { $line == "OVER" } { 
      return $r
    }
    append r $line
  }
}

# Write the main loop for the child testfixture processes into file
# tf_main2.tcl. The parent (this script) interacts with the child processes
# via a two way pipe. The parent writes a script to the stdin of the child
# process, followed by the word "OVER" on a line of its own. The child
# process evaluates the script and writes the results to stdout, followed
# by an "OVER" of its own.
set f [open tf_main2.tcl w]
puts $f {
  set l [open log w]
  set script ""
  while {![eof stdin]} {
    flush stdout
    set line [gets stdin]
    puts $l "READ $line"
    if { $line == "OVER" } {
      catch {eval $script} result
      puts $result
      puts $l "WRITE $result"
      puts OVER
      puts $l "WRITE OVER"
      flush stdout
      set script ""
    } else {
      append script $line
      append script " ; "
    }
  }
  close $l
}
close $f


ifcapable lock_proxy_pragmas {
  set sqlite_hostid_num 1

  set using_proxy 0
  foreach {name value} [array get env SQLITE_FORCE_PROXY_LOCKING] {
    set using_proxy $value
  }

  # Test the lock_proxy_file pragmas.
  #
  set env(SQLITE_FORCE_PROXY_LOCKING) "1"

  do_test lock6-1.1 {
    set ::tf1 [launch_testfixture]
    testfixture $::tf1 "set sqlite_pending_byte $::sqlite_pending_byte"
    testfixture $::tf1 {
      set sqlite_hostid_num 2    
      sqlite3 db test.db -key xyzzy
      set lockpath [db eval {
        PRAGMA lock_proxy_file=":auto:";
        select * from sqlite_master;
        PRAGMA lock_proxy_file;
      }]
      string match "*test.db:auto:" $lockpath
    }
  } {1}
  
  set sqlite_hostid_num 3   
  do_test lock6-1.2 {
    execsql {pragma lock_status}
  } {main unlocked temp closed}

  sqlite3_soft_heap_limit 0
  do_test lock6-1.3 {
    sqlite3 db test.db
    catchsql {
      select * from sqlite_master;
    } 
  } {1 {database is locked}}

  do_test lock6-1.4 {
    set lockpath [execsql {
      PRAGMA lock_proxy_file=":auto:";
      PRAGMA lock_proxy_file;
    } db]
    set lockpath
  } {{:auto: (not held)}}

  do_test lock6-1.4.1 {
    catchsql {
      PRAGMA lock_proxy_file="notmine";
      select * from sqlite_master;
    } db
  } {1 {database is locked}}

  do_test lock6-1.4.2 {
    execsql {
      PRAGMA lock_proxy_file;
    } db
  } {notmine}
    
  do_test lock6-1.5 {
    testfixture $::tf1 {
      db eval {
        BEGIN;
        SELECT * FROM sqlite_master;
      }
    }
  } {}

  catch {testfixture $::tf1 {db close}}

  do_test lock6-1.6 {
    execsql {
      PRAGMA lock_proxy_file="mine";
      select * from sqlite_master;
    } db
  } {}
  
  catch {close $::tf1}
  set env(SQLITE_FORCE_PROXY_LOCKING) $using_proxy
  set sqlite_hostid_num 0

  sqlite3_soft_heap_limit $soft_limit

}
      
finish_test

#
#***********************************************************************
# This file implements regression tests for SQLite library.
#
# This file implements tests the ability of the library to open
# many different databases at the same time without leaking memory.
#
# $Id: manydb.test,v 1.4 2008/11/21 00:10:35 aswift Exp $

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

set N 300
# if we're using proxy locks, we use 5 filedescriptors for a db
# that is open and in the middle of writing changes, normally
# sqlite uses 3 (proxy locking adds the conch and the local lock)
set using_proxy 0
foreach {name value} [array get env SQLITE_FORCE_PROXY_LOCKING] {
  set using_proxy value
}
set num_fd_per_openwrite_db 3
if {$using_proxy>0} {
  set num_fd_per_openwrite_db 5
} 

# First test how many file descriptors are available for use. To open a
# database for writing SQLite requires 3 file descriptors (the database, the
# journal and the directory).
set filehandles {}
catch {
  for {set i 0} {$i<($N * 3)} {incr i} {
    lappend filehandles [open testfile.1 w]
  }
}
foreach fd $filehandles {
  close $fd
}
catch {
  file delete -force testfile.1
}
set N [expr $i / $num_fd_per_openwrite_db]

# Create a bunch of random database names
#
unset -nocomplain dbname
unset -nocomplain used
for {set i 0} {$i<$N} {incr i} {
  while 1 {

#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.
#
# This file implements tests for the PRAGMA command.
#
# $Id: pragma.test,v 1.70 2008/11/21 00:10:35 aswift Exp $

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

# Test organization:
#
# pragma-1.*: Test cache_size, default_cache_size and synchronous on main db.

# pragma-8.*: Test user_version and schema_version pragmas.
# pragma-9.*: Test temp_store and temp_store_directory.
# pragma-10.*: Test the count_changes pragma in the presence of triggers.
# pragma-11.*: Test the collation_list pragma.
# pragma-14.*: Test the page_count pragma.
# pragma-15.*: Test that the value set using the cache_size pragma is not
#              reset when the schema is reloaded.
# pragma-16.*: Test proxy locking
#

ifcapable !pragma {
  finish_test
  return
}

}

# Reset the sqlite3_temp_directory variable for the next run of tests:
sqlite3 dbX :memory:
dbX eval {PRAGMA temp_store_directory = ""}
dbX close

ifcapable lock_proxy_pragmas {
  set sqlite_hostid_num 1

  set using_proxy 0
  foreach {name value} [array get env SQLITE_FORCE_PROXY_LOCKING] {
    set using_proxy $value
  }

  # Test the lock_proxy_file pragmas.
  #
  db close
  set env(SQLITE_FORCE_PROXY_LOCKING) "0"

  sqlite3 db test.db
  do_test pragma-16.1 {
    execsql {
      PRAGMA lock_proxy_file="mylittleproxy";
      select * from sqlite_master;
    }
    execsql {
      PRAGMA lock_proxy_file;
    } 
  } {mylittleproxy}

  do_test pragma-16.2 {
    sqlite3 db2 test.db
    execsql {
      PRAGMA lock_proxy_file="mylittleproxy";
    } db2
  } {}

  db2 close
  do_test pragma-16.2.1 {
    sqlite3 db2 test.db
    execsql {
      PRAGMA lock_proxy_file=":auto:";
      select * from sqlite_master;
    } db2
    execsql {
      PRAGMA lock_proxy_file;
    } db2
  } {mylittleproxy}

  db2 close
  do_test pragma-16.3 {
    sqlite3 db2 test.db
    execsql {
      PRAGMA lock_proxy_file="myotherproxy";
    } db2
    catchsql {
      select * from sqlite_master;
    } db2
  } {1 {database is locked}}

  do_test pragma-16.4 {
    db2 close
    db close
    sqlite3 db2 test.db
    execsql {
      PRAGMA lock_proxy_file="myoriginalproxy";
      PRAGMA lock_proxy_file="myotherproxy";
      PRAGMA lock_proxy_file;
    } db2
  } {myotherproxy}

  db2 close
  set env(SQLITE_FORCE_PROXY_LOCKING) "1"
  do_test pragma-16.5 {
    sqlite3 db2 test.db
    execsql {
      PRAGMA lock_proxy_file=":auto:";
      PRAGMA lock_proxy_file;
    } db2
  } {myotherproxy}
  
  do_test pragma-16.6 {
    db2 close
    sqlite3 db2 test2.db
    set lockpath [execsql {
      PRAGMA lock_proxy_file=":auto:";
      PRAGMA lock_proxy_file;
    } db2]
    string match "*test2.db:auto:" $lockpath
  } {1}
  
  set sqlite_hostid_num 2
  do_test pragma-16.7 {
    sqlite3 db test2.db
    execsql {
      PRAGMA lock_proxy_file=":auto:";
    } 
    catchsql {
      select * from sqlite_master;
    }
  } {1 {database is locked}}
  db close
  
  do_test pragma-16.8 {
    sqlite3 db test2.db
    catchsql {
      select * from sqlite_master;
    } 
  } {1 {database is locked}}

  db2 close
  do_test pragma-16.8.1 {
    execsql {
      PRAGMA lock_proxy_file="yetanotherproxy";
      PRAGMA lock_proxy_file;
    } 
  } {yetanotherproxy}
  do_test pragma-16.8.2 {
    execsql {
      create table mine(x);
    } 
  } {}

  db close
  do_test pragma-16.9 {
    sqlite3 db proxytest.db
    set lockpath2 [execsql {
      PRAGMA lock_proxy_file=":auto:";
      PRAGMA lock_proxy_file;
    } db]
    string match "*proxytest.db:auto:" $lockpath2
  } {1}

  set env(SQLITE_FORCE_PROXY_LOCKING) $using_proxy
  set sqlite_hostid_num 0
}
finish_test

# 2005 December 30
#
# 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.
#
#***********************************************************************
#
# $Id: shared.test,v 1.35 2008/11/21 00:10:35 aswift Exp $

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

# These tests cannot be run without the ATTACH command.
#

  } "$av"
} else {
  if {$av} {
    db close
    break
  }
}

# if we're using proxy locks, we use 2 filedescriptors for a db
# that is open but NOT yet locked, after a lock is taken we'll have 3, 
# normally sqlite uses 1 (proxy locking adds the conch and the local lock)
set using_proxy 0
foreach {name value} [array get env SQLITE_FORCE_PROXY_LOCKING] {
  set using_proxy $value
}
set extrafds_prelock 0
set extrafds_postlock 0
if {$using_proxy>0} {
  set extrafds_prelock 1
  set extrafds_postlock 2
} 

# $av is currently 0 if this loop iteration is to test with auto-vacuum turned
# off, and 1 if it is turned on. Increment it so that (1 -> no auto-vacuum) 
# and (2 -> auto-vacuum). The sole reason for this is so that it looks nicer
# when we use this variable as part of test-case names.
#
incr av

do_test shared-$av.1.1 {
  # Open a second database on the file test.db. It should use the same pager
  # cache and schema as the original connection. Verify that only 1 file is 
  # opened.
  sqlite3 db2 test.db
  set ::sqlite_open_file_count
  expr $sqlite_open_file_count-$extrafds_postlock
} {1}
do_test shared-$av.1.2 {
  # Add a table and a single row of data via the first connection. 
  # Ensure that the second connection can see them.
  execsql {
    CREATE TABLE abc(a, b, c);
    INSERT INTO abc VALUES(1, 2, 3);

  # (there should be two open file handles).
  if {$::tcl_platform(platform)=="unix"} {
    sqlite3 db3 ./test.db
  } else {
    sqlite3 db3 TEST.DB
  }
  set ::sqlite_open_file_count
  expr $sqlite_open_file_count-($extrafds_prelock+$extrafds_postlock)
} {2}
do_test shared-$av.2.2 {
  # Start read transactions on db and db2 (the shared pager cache). Ensure
  # db3 cannot write to the database.
  execsql {
    BEGIN;
    SELECT * FROM abc;

file delete -force test.db
file delete -force test2.db
file delete -force test2.db-journal
sqlite3 db  test.db
sqlite3 db2 test2.db
do_test shared-$av.4.1.1 {
  set sqlite_open_file_count
  expr $sqlite_open_file_count-($extrafds_prelock*2)
} {2}
do_test shared-$av.4.1.2 {
  execsql {ATTACH 'test2.db' AS test2}
  set sqlite_open_file_count
  expr $sqlite_open_file_count-($extrafds_postlock*2)
} {2}
do_test shared-$av.4.1.3 {
  execsql {ATTACH 'test.db' AS test} db2
  set sqlite_open_file_count
  expr $sqlite_open_file_count-($extrafds_postlock*2)
} {2}

# Sanity check: Create a table in ./test.db via handle db, and test that handle
# db2 can "see" the new table immediately. A handle using a seperate pager
# cache would have to reload the database schema before this were possible.
#
do_test shared-$av.4.2.1 {

# 2001 September 15
#
# 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 some common TCL routines used for regression
# testing the SQLite library
#
# $Id: tester.tcl,v 1.135 2008/11/21 00:10:35 aswift Exp $

#
# What for user input before continuing.  This gives an opportunity
# to connect profiling tools to the process.
#
for {set i 0} {$i<[llength $argv]} {incr i} {
  if {[regexp {^-+pause$} [lindex $argv $i] all value]} {

    }

    # Delete the files test.db and test2.db, then execute the TCL and 
    # SQL (in that order) to prepare for the test case.
    do_test $testname.$n.1 {
      set ::sqlite_io_error_pending 0
      catch {db close}
      catch {db2 close}
      catch {file delete -force test.db}
      catch {file delete -force test.db-journal}
      catch {file delete -force test2.db}
      catch {file delete -force test2.db-journal}
      set ::DB [sqlite3 db test.db; sqlite3_connection_pointer db]
      sqlite3_extended_result_codes $::DB $::ioerropts(-erc)
      if {[info exists ::ioerropts(-tclprep)]} {