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Overview
Comment:Align the os_unix.c source file with the version found on trunk.
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Timelines: family | ancestors | descendants | both | apple-osx
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SHA1:fa0f6c140e8ff9a5eed1d8a339fb6d55ecdca688
User & Date: drh 2010-01-20 13:20:23
Context
2010-01-26
01:14
Updated open mask to include SQLITE_OPEN_AUTOPROXY check-in: 7c3bede3 user: adam tags: apple-osx
2010-01-20
13:20
Align the os_unix.c source file with the version found on trunk. check-in: fa0f6c14 user: drh tags: apple-osx
13:07
Move the Apple OS-X VFS changes into the trunk. check-in: 571594bf user: drh tags: trunk
01:26
Update the Apple OS-X branch to include all of the latest changes in trunk. check-in: 96499b1d user: drh tags: apple-osx
Changes
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Changes to src/os_unix.c.

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# else
#  include <sys/file.h>
#  include <sys/param.h>
#  include <sys/mount.h>
# endif
#endif /* SQLITE_ENABLE_LOCKING_STYLE */

#define SQLITE_FSFLAGS_IS_READONLY  0x1
#define SQLITE_FSFLAGS_IS_LOCAL     0x2
#define SQLITE_FSFLAGS_IS_HFSPLUS   0x4
#define SQLITE_FSFLAGS_IS_MSDOS     0x8
#define SQLITE_FSFLAGS_INITIALIZED     0x10000


/*
** If we are to be thread-safe, include the pthreads header and define
** the SQLITE_UNIX_THREADS macro.
*/
#if SQLITE_THREADSAFE
# include <pthread.h>
................................................................................
  ** 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 ) && (0 != (pFile->fsFlags & SQLITE_FSFLAGS_IS_MSDOS))) {
      rc = write(fd, "S", 1);
      if( rc!=1 ){
        pFile->lastErrno = errno;
        return SQLITE_IOERR;
      }
      rc = fstat(fd, &statbuf);
      if( rc!=0 ){
        pFile->lastErrno = errno;
        return SQLITE_IOERR;
      }
    }
#endif

  memset(&lockKey, 0, sizeof(lockKey));
  lockKey.fid.dev = statbuf.st_dev;
#if OS_VXWORKS
  lockKey.fid.pId = pFile->pId;
#else
................................................................................
  unixLeaveMutex();
  OSTRACE4("TEST WR-LOCK %d %d %d (unix)\n", pFile->h, rc, reserved);

  *pResOut = reserved;
  return rc;
}

#ifdef SQLITE_ENABLE_NFS_RANGELOCK
/*
** Perform a file locking operation on a range of bytes in a file.
** The "op" parameter should be one of F_RDLCK, F_WRLCK, or F_UNLCK.
** Return 0 on success or -1 for failure.  On failure, write the error
** code into *pErrcode.
**
** If the SQLITE_WHOLE_FILE_LOCKING bit is clear, then only lock
** the range of bytes on the locking page between SHARED_FIRST and
** SHARED_SIZE.  If SQLITE_WHOLE_FILE_LOCKING is set, then lock all
** bytes from 0 up to but not including PENDING_BYTE, and all bytes
** that follow SHARED_FIRST.
**
** In other words, of SQLITE_WHOLE_FILE_LOCKING if false (the historical
** default case) then only lock a small range of bytes from SHARED_FIRST
** through SHARED_FIRST+SHARED_SIZE-1.  But if SQLITE_WHOLE_FILE_LOCKING is
** true then lock every byte in the file except for PENDING_BYTE and
** RESERVED_BYTE.
**
** SQLITE_WHOLE_FILE_LOCKING=true overlaps SQLITE_WHOLE_FILE_LOCKING=false
** and so the locking schemes are compatible.  One type of lock will
** effectively exclude the other type.  The reason for using the
** SQLITE_WHOLE_FILE_LOCKING=true is that by indicating the full range
** of bytes to be read or written, we give hints to NFS to help it
** maintain cache coherency.  On the other hand, whole file locking
** is slower, so we don't want to use it except for NFS.
*/
static int rangeLock(unixFile *pFile, int op, int *pErrcode){
  struct flock lock;
  int rc;
  lock.l_type = op;
  lock.l_start = SHARED_FIRST;
  lock.l_whence = SEEK_SET;
  if( (pFile->fileFlags & SQLITE_WHOLE_FILE_LOCKING)==0 ){
    lock.l_len = SHARED_SIZE;
    rc = fcntl(pFile->h, F_SETLK, &lock);
    *pErrcode = errno;
  }else{
    lock.l_len = 0;
    rc = fcntl(pFile->h, F_SETLK, &lock);
    *pErrcode = errno;
    if( NEVER(op==F_UNLCK) || rc!=(-1) ){
      lock.l_start = 0;
      lock.l_len = PENDING_BYTE;
      rc = fcntl(pFile->h, F_SETLK, &lock);
      if( ALWAYS(op!=F_UNLCK) && rc==(-1) ){
        *pErrcode = errno;
        lock.l_type = F_UNLCK;
        lock.l_start = SHARED_FIRST;
        lock.l_len = 0;
        fcntl(pFile->h, F_SETLK, &lock);
      }
    }
  }
  return rc;
}

#endif /* SQLITE_ENABLE_NFS_RANGELOCK */
/*
** Lock the file with the lock specified by parameter locktype - one
** of the following:
**
**     (1) SHARED_LOCK
**     (2) RESERVED_LOCK
**     (3) PENDING_LOCK
................................................................................
    assert( pFile->inNormalWrite==0
         || pFile->dbUpdate==0
         || pFile->transCntrChng==1 );
    pFile->inNormalWrite = 0;
#endif

    /* downgrading to a shared lock on NFS involves clearing the write lock
     ** before establishing the readlock - to avoid a race condition we downgrade
     ** the lock in 2 blocks, so that part of the range will be covered by a 
     ** write lock until the rest is covered by a read lock:
     **  1:   [WWWWW]
     **  2:   [....W]
     **  3:   [RRRRW]
     **  4:   [RRRR.]
     */
    if( locktype==SHARED_LOCK ){
      if( handleNFSUnlock ){
        off_t divSize = SHARED_SIZE - 1;
        
        lock.l_type = F_UNLCK;
        lock.l_whence = SEEK_SET;
        lock.l_start = SHARED_FIRST;
................................................................................
    assert( pLock->locktype==pFile->locktype );
    SimulateIOErrorBenign(1);
    SimulateIOError( h=(-1) )
    SimulateIOErrorBenign(0);
    
#ifndef NDEBUG
    /* When reducing a lock such that other processes can start
     ** reading the database file again, make sure that the
     ** transaction counter was updated if any part of the database
     ** file changed.  If the transaction counter is not updated,
     ** other connections to the same file might not realize that
     ** the file has changed and hence might not know to flush their
     ** cache.  The use of a stale cache can lead to database corruption.
     */
    assert( pFile->inNormalWrite==0
           || pFile->dbUpdate==0
           || pFile->transCntrChng==1 );
    pFile->inNormalWrite = 0;
#endif
    
    if( pFile->locktype==EXCLUSIVE_LOCK ){
................................................................................
    if( rc==SQLITE_OK && (locktype==SHARED_LOCK || pLock->cnt>1)){
      pLock->locktype = SHARED_LOCK;
    }
  }
  if( rc==SQLITE_OK && locktype==NO_LOCK ){

    /* Decrement the shared lock counter.  Release the lock using an
     ** OS call only when all threads in this same process have released
     ** the lock.
     */
    unsigned long long sharedLockByte = SHARED_FIRST+pLock->sharedByte;
    pLock->cnt--;
    if( pLock->cnt==0 ){
      SimulateIOErrorBenign(1);
      SimulateIOError( h=(-1) )
      SimulateIOErrorBenign(0);
      if( !skipShared ){
................................................................................
  ** and (for now) ignore the overhead of a superfluous fcntl call.  
  ** It'd be better to detect fullfsync support once and avoid 
  ** the fcntl call every time sync is called.
  */
  if( rc ) rc = fsync(fd);

#elif defined(__APPLE__)
  // fdatasync() on HFS+ doesn't yet flush the file size if it changed correctly
	// so currently we default to the macro that redefines fdatasync to fsync

  rc = fsync(fd);
#else 
  rc = fdatasync(fd);
#if OS_VXWORKS
  if( rc==-1 && errno==ENOTSUP ){
    rc = fsync(fd);
  }
................................................................................
  int rc = SQLITE_OK;            /* Function Return Code */

  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);

  int isAutoProxy  = (flags & SQLITE_OPEN_AUTOPROXY);


  /* If creating a master or main-file journal, this function will open
  ** a file-descriptor on the directory too. The first time unixSync()
  ** is called the directory file descriptor will be fsync()ed and close()d.
  */
  int isOpenDirectory = (isCreate && 
      (eType==SQLITE_OPEN_MASTER_JOURNAL || eType==SQLITE_OPEN_MAIN_JOURNAL)
................................................................................

#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
  isAutoProxy = 1;
#endif
  
#if defined(__APPLE__) || SQLITE_ENABLE_LOCKING_STYLE

  struct statfs fsInfo;
  if( fstatfs(fd, &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;
  }
  
  ((unixFile*)pFile)->fsFlags = SQLITE_FSFLAGS_INITIALIZED;
  
  if (fsInfo.f_flags & MNT_RDONLY) {
    ((unixFile*)pFile)->fsFlags |= SQLITE_FSFLAGS_IS_READONLY;
  }
  if (fsInfo.f_flags & MNT_LOCAL) {
    ((unixFile*)pFile)->fsFlags |= SQLITE_FSFLAGS_IS_LOCAL;
  }
  if (0 == strncmp("hfs", fsInfo.f_fstypename, 3)) {
    ((unixFile*)pFile)->fsFlags |= SQLITE_FSFLAGS_IS_HFSPLUS;
  } else if (0 == strncmp("msdos", fsInfo.f_fstypename, 5)) {
    ((unixFile*)pFile)->fsFlags |= SQLITE_FSFLAGS_IS_MSDOS;
  }
#endif
  
#if SQLITE_ENABLE_LOCKING_STYLE



  if( isAutoProxy && (zPath!=NULL) && (!noLock) && pVfs->xOpen ){
    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 ){
................................................................................

#ifdef LOCKPROXYDIR
  len = strlcpy(lPath, LOCKPROXYDIR, maxLen);
#else
# ifdef _CS_DARWIN_USER_TEMP_DIR
  {
    if( !confstr(_CS_DARWIN_USER_TEMP_DIR, lPath, maxLen) ){
      OSTRACE4("GETLOCKPATH  failed %s errno=%d pid=%d\n", lPath, errno, getpid());

      return SQLITE_IOERR_LOCK;
    }
    len = strlcat(lPath, "sqliteplocks", maxLen);    
  }
# else
  len = strlcpy(lPath, "/tmp/", maxLen);
# endif
................................................................................
      /* only mkdir if leaf dir != "." or "/" or ".." */
      if( i-start>2 || (i-start==1 && buf[start] != '.' && buf[start] != '/') 
         || (i-start==2 && buf[start] != '.' && buf[start+1] != '.') ){
        buf[i]='\0';
        if( mkdir(buf, SQLITE_DEFAULT_PROXYDIR_PERMISSIONS) ){
          int err=errno;
          if( err!=EEXIST ) {
            OSTRACE5("CREATELOCKPATH  FAILED creating %s, '%s' proxy lock path=%s pid=%d\n", buf, strerror(err), lockPath, getpid());


            return err;
          }
        }
      }
      start=i+1;
    }
    buf[i] = lockPath[i];
................................................................................
            memcpy(lockPath, &readBuf[PROXY_PATHINDEX], pathLen);
            lockPath[pathLen] = 0;
            tempLockPath = lockPath;
            tryOldLockPath = 1;
            /* create a copy of the lock path if the conch is taken */
            goto end_takeconch;
          }

        }else if( hostIdMatch && !strncmp(pCtx->lockProxyPath, 
                                          &readBuf[PROXY_PATHINDEX], readLen-PROXY_PATHINDEX) ){

          /* conch host and lock path match */
          goto end_takeconch; 
        }
      }
      
      /* if the conch isn't writable and doesn't match, we can't take it */
      if( (conchFile->openFlags&O_RDWR) == 0 ){







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# else
#  include <sys/file.h>
#  include <sys/param.h>
#  include <sys/mount.h>
# endif
#endif /* SQLITE_ENABLE_LOCKING_STYLE */

/*
** Allowed values of unixFile.fsFlags
*/
#define SQLITE_FSFLAGS_IS_MSDOS     0x1



/*
** If we are to be thread-safe, include the pthreads header and define
** the SQLITE_UNIX_THREADS macro.
*/
#if SQLITE_THREADSAFE
# include <pthread.h>
................................................................................
  ** 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 && (pFile->fsFlags & SQLITE_FSFLAGS_IS_MSDOS)!=0 ){
    rc = write(fd, "S", 1);
    if( rc!=1 ){
      pFile->lastErrno = errno;
      return SQLITE_IOERR;
    }
    rc = fstat(fd, &statbuf);
    if( rc!=0 ){
      pFile->lastErrno = errno;
      return SQLITE_IOERR;
    }
  }
#endif

  memset(&lockKey, 0, sizeof(lockKey));
  lockKey.fid.dev = statbuf.st_dev;
#if OS_VXWORKS
  lockKey.fid.pId = pFile->pId;
#else
................................................................................
  unixLeaveMutex();
  OSTRACE4("TEST WR-LOCK %d %d %d (unix)\n", pFile->h, rc, reserved);

  *pResOut = reserved;
  return rc;
}



























































/*
** Lock the file with the lock specified by parameter locktype - one
** of the following:
**
**     (1) SHARED_LOCK
**     (2) RESERVED_LOCK
**     (3) PENDING_LOCK
................................................................................
    assert( pFile->inNormalWrite==0
         || pFile->dbUpdate==0
         || pFile->transCntrChng==1 );
    pFile->inNormalWrite = 0;
#endif

    /* downgrading to a shared lock on NFS involves clearing the write lock
    ** before establishing the readlock - to avoid a race condition we downgrade
    ** the lock in 2 blocks, so that part of the range will be covered by a 
    ** write lock until the rest is covered by a read lock:
    **  1:   [WWWWW]
    **  2:   [....W]
    **  3:   [RRRRW]
    **  4:   [RRRR.]
    */
    if( locktype==SHARED_LOCK ){
      if( handleNFSUnlock ){
        off_t divSize = SHARED_SIZE - 1;
        
        lock.l_type = F_UNLCK;
        lock.l_whence = SEEK_SET;
        lock.l_start = SHARED_FIRST;
................................................................................
    assert( pLock->locktype==pFile->locktype );
    SimulateIOErrorBenign(1);
    SimulateIOError( h=(-1) )
    SimulateIOErrorBenign(0);
    
#ifndef NDEBUG
    /* When reducing a lock such that other processes can start
    ** reading the database file again, make sure that the
    ** transaction counter was updated if any part of the database
    ** file changed.  If the transaction counter is not updated,
    ** other connections to the same file might not realize that
    ** the file has changed and hence might not know to flush their
    ** cache.  The use of a stale cache can lead to database corruption.
    */
    assert( pFile->inNormalWrite==0
           || pFile->dbUpdate==0
           || pFile->transCntrChng==1 );
    pFile->inNormalWrite = 0;
#endif
    
    if( pFile->locktype==EXCLUSIVE_LOCK ){
................................................................................
    if( rc==SQLITE_OK && (locktype==SHARED_LOCK || pLock->cnt>1)){
      pLock->locktype = SHARED_LOCK;
    }
  }
  if( rc==SQLITE_OK && locktype==NO_LOCK ){

    /* Decrement the shared lock counter.  Release the lock using an
    ** OS call only when all threads in this same process have released
    ** the lock.
    */
    unsigned long long sharedLockByte = SHARED_FIRST+pLock->sharedByte;
    pLock->cnt--;
    if( pLock->cnt==0 ){
      SimulateIOErrorBenign(1);
      SimulateIOError( h=(-1) )
      SimulateIOErrorBenign(0);
      if( !skipShared ){
................................................................................
  ** and (for now) ignore the overhead of a superfluous fcntl call.  
  ** It'd be better to detect fullfsync support once and avoid 
  ** the fcntl call every time sync is called.
  */
  if( rc ) rc = fsync(fd);

#elif defined(__APPLE__)
  /* fdatasync() on HFS+ doesn't yet flush the file size if it changed correctly
  ** so currently we default to the macro that redefines fdatasync to fsync
  */
  rc = fsync(fd);
#else 
  rc = fdatasync(fd);
#if OS_VXWORKS
  if( rc==-1 && errno==ENOTSUP ){
    rc = fsync(fd);
  }
................................................................................
  int rc = SQLITE_OK;            /* Function Return Code */

  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);
#if SQLITE_ENABLE_LOCKING_STYLE
  int isAutoProxy  = (flags & SQLITE_OPEN_AUTOPROXY);
#endif

  /* If creating a master or main-file journal, this function will open
  ** a file-descriptor on the directory too. The first time unixSync()
  ** is called the directory file descriptor will be fsync()ed and close()d.
  */
  int isOpenDirectory = (isCreate && 
      (eType==SQLITE_OPEN_MASTER_JOURNAL || eType==SQLITE_OPEN_MAIN_JOURNAL)
................................................................................

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

  noLock = eType!=SQLITE_OPEN_MAIN_DB;




  
#if defined(__APPLE__) || SQLITE_ENABLE_LOCKING_STYLE

  struct statfs fsInfo;
  if( fstatfs(fd, &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;
  }











  if (0 == strncmp("msdos", fsInfo.f_fstypename, 5)) {
    ((unixFile*)pFile)->fsFlags |= SQLITE_FSFLAGS_IS_MSDOS;
  }
#endif
  
#if SQLITE_ENABLE_LOCKING_STYLE
#if SQLITE_PREFER_PROXY_LOCKING
  isAutoProxy = 1;
#endif
  if( isAutoProxy && (zPath!=NULL) && (!noLock) && pVfs->xOpen ){
    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 ){
................................................................................

#ifdef LOCKPROXYDIR
  len = strlcpy(lPath, LOCKPROXYDIR, maxLen);
#else
# ifdef _CS_DARWIN_USER_TEMP_DIR
  {
    if( !confstr(_CS_DARWIN_USER_TEMP_DIR, lPath, maxLen) ){
      OSTRACE4("GETLOCKPATH  failed %s errno=%d pid=%d\n",
               lPath, errno, getpid());
      return SQLITE_IOERR_LOCK;
    }
    len = strlcat(lPath, "sqliteplocks", maxLen);    
  }
# else
  len = strlcpy(lPath, "/tmp/", maxLen);
# endif
................................................................................
      /* only mkdir if leaf dir != "." or "/" or ".." */
      if( i-start>2 || (i-start==1 && buf[start] != '.' && buf[start] != '/') 
         || (i-start==2 && buf[start] != '.' && buf[start+1] != '.') ){
        buf[i]='\0';
        if( mkdir(buf, SQLITE_DEFAULT_PROXYDIR_PERMISSIONS) ){
          int err=errno;
          if( err!=EEXIST ) {
            OSTRACE5("CREATELOCKPATH  FAILED creating %s, "
                     "'%s' proxy lock path=%s pid=%d\n",
                     buf, strerror(err), lockPath, getpid());
            return err;
          }
        }
      }
      start=i+1;
    }
    buf[i] = lockPath[i];
................................................................................
            memcpy(lockPath, &readBuf[PROXY_PATHINDEX], pathLen);
            lockPath[pathLen] = 0;
            tempLockPath = lockPath;
            tryOldLockPath = 1;
            /* create a copy of the lock path if the conch is taken */
            goto end_takeconch;
          }
        }else if( hostIdMatch
               && !strncmp(pCtx->lockProxyPath, &readBuf[PROXY_PATHINDEX],
                           readLen-PROXY_PATHINDEX)
        ){
          /* conch host and lock path match */
          goto end_takeconch; 
        }
      }
      
      /* if the conch isn't writable and doesn't match, we can't take it */
      if( (conchFile->openFlags&O_RDWR) == 0 ){