/ Check-in [725c1c14]
Login

Many hyperlinks are disabled.
Use anonymous login to enable hyperlinks.

Overview
Comment:Take out the special handling of nolock=true in os_win.c and add it to pager.c, so that it works for all VFSes. Add the pPager->noLock boolean for clarity.
Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | win32-none
Files: files | file ages | folders
SHA1:725c1c14be331bce9bf074960dbfa7b6d4c1ba87
User & Date: drh 2014-05-01 01:49:22
Context
2014-05-07
15:09
Add test cases and documentation for the nolock and immutable query parameters. check-in: 19d56cba user: drh tags: win32-none
2014-05-01
01:49
Take out the special handling of nolock=true in os_win.c and add it to pager.c, so that it works for all VFSes. Add the pPager->noLock boolean for clarity. check-in: 725c1c14 user: drh tags: win32-none
01:20
Avoid unnecessary xUnlock operations on temp file. check-in: 1829c38c user: drh tags: win32-none
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to src/os_win.c.

271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
....
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
....
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
....
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
....
4700
4701
4702
4703
4704
4705
4706
4707
4708
4709
4710
4711
4712
4713
4714
4715
4716

/*
** Allowed values for winFile.ctrlFlags
*/
#define WINFILE_RDONLY          0x02   /* Connection is read only */
#define WINFILE_PERSIST_WAL     0x04   /* Persistent WAL mode */
#define WINFILE_PSOW            0x10   /* SQLITE_IOCAP_POWERSAFE_OVERWRITE */
#define WINFILE_NOLOCK          0x20   /* Never do any real locking */

/*
 * The size of the buffer used by sqlite3_win32_write_debug().
 */
#ifndef SQLITE_WIN32_DBG_BUF_SIZE
#  define SQLITE_WIN32_DBG_BUF_SIZE   ((int)(4096-sizeof(DWORD)))
#endif
................................................................................
  int gotPendingLock = 0;/* True if we acquired a PENDING lock this time */
  winFile *pFile = (winFile*)id;
  DWORD lastErrno = NO_ERROR;

  assert( id!=0 );
  OSTRACE(("LOCK file=%p, oldLock=%d(%d), newLock=%d\n",
           pFile->h, pFile->locktype, pFile->sharedLockByte, locktype));
  if( pFile->ctrlFlags & WINFILE_NOLOCK ){
    OSTRACE(("LOCK-NOP file=%p, rc=SQLITE_OK\n", pFile->h));
    return SQLITE_OK;
  }

  /* If there is already a lock of this type or more restrictive on the
  ** OsFile, do nothing. Don't use the end_lock: exit path, as
  ** sqlite3OsEnterMutex() hasn't been called yet.
  */
  if( pFile->locktype>=locktype ){
    OSTRACE(("LOCK-HELD file=%p, rc=SQLITE_OK\n", pFile->h));
................................................................................
  int rc;
  winFile *pFile = (winFile*)id;

  SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
  OSTRACE(("TEST-WR-LOCK file=%p, pResOut=%p\n", pFile->h, pResOut));

  assert( id!=0 );
  if( pFile->ctrlFlags & WINFILE_NOLOCK ){
    rc = 0;
    OSTRACE(("TEST-WR-LOCK file=%p, rc=%d (nop)\n", pFile->h, rc));
  }else if( pFile->locktype>=RESERVED_LOCK ){
    rc = 1;
    OSTRACE(("TEST-WR-LOCK file=%p, rc=%d (local)\n", pFile->h, rc));
  }else{
    rc = winLockFile(&pFile->h, SQLITE_LOCKFILEEX_FLAGS,RESERVED_BYTE, 0, 1, 0);
    if( rc ){
      winUnlockFile(&pFile->h, RESERVED_BYTE, 0, 1, 0);
    }
................................................................................
  int type;
  winFile *pFile = (winFile*)id;
  int rc = SQLITE_OK;
  assert( pFile!=0 );
  assert( locktype<=SHARED_LOCK );
  OSTRACE(("UNLOCK file=%p, oldLock=%d(%d), newLock=%d\n",
           pFile->h, pFile->locktype, pFile->sharedLockByte, locktype));
  if( pFile->ctrlFlags & WINFILE_NOLOCK ){
    OSTRACE(("UNLOCK-NOP file=%p, rc=SQLITE_OK\n", pFile->h));
    return SQLITE_OK;
  }
  type = pFile->locktype;
  if( type>=EXCLUSIVE_LOCK ){
    winUnlockFile(&pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
    if( locktype==SHARED_LOCK && !winGetReadLock(pFile) ){
      /* This should never happen.  We should always be able to
      ** reacquire the read lock */
      rc = winLogError(SQLITE_IOERR_UNLOCK, osGetLastError(),
................................................................................
  pFile->h = h;
  if( isReadonly ){
    pFile->ctrlFlags |= WINFILE_RDONLY;
  }
  if( sqlite3_uri_boolean(zName, "psow", SQLITE_POWERSAFE_OVERWRITE) ){
    pFile->ctrlFlags |= WINFILE_PSOW;
  }
  if( sqlite3_uri_boolean(zName, "nolock", 0) ){
    pFile->ctrlFlags |= WINFILE_NOLOCK;
  }
  pFile->lastErrno = NO_ERROR;
  pFile->zPath = zName;
#if SQLITE_MAX_MMAP_SIZE>0
  pFile->hMap = NULL;
  pFile->pMapRegion = 0;
  pFile->mmapSize = 0;
  pFile->mmapSizeActual = 0;







<







 







<
<
<
<







 







<
<
<
|







 







<
<
<
<







 







<
<
<







271
272
273
274
275
276
277

278
279
280
281
282
283
284
....
2855
2856
2857
2858
2859
2860
2861




2862
2863
2864
2865
2866
2867
2868
....
2982
2983
2984
2985
2986
2987
2988



2989
2990
2991
2992
2993
2994
2995
2996
....
3018
3019
3020
3021
3022
3023
3024




3025
3026
3027
3028
3029
3030
3031
....
4688
4689
4690
4691
4692
4693
4694



4695
4696
4697
4698
4699
4700
4701

/*
** Allowed values for winFile.ctrlFlags
*/
#define WINFILE_RDONLY          0x02   /* Connection is read only */
#define WINFILE_PERSIST_WAL     0x04   /* Persistent WAL mode */
#define WINFILE_PSOW            0x10   /* SQLITE_IOCAP_POWERSAFE_OVERWRITE */


/*
 * The size of the buffer used by sqlite3_win32_write_debug().
 */
#ifndef SQLITE_WIN32_DBG_BUF_SIZE
#  define SQLITE_WIN32_DBG_BUF_SIZE   ((int)(4096-sizeof(DWORD)))
#endif
................................................................................
  int gotPendingLock = 0;/* True if we acquired a PENDING lock this time */
  winFile *pFile = (winFile*)id;
  DWORD lastErrno = NO_ERROR;

  assert( id!=0 );
  OSTRACE(("LOCK file=%p, oldLock=%d(%d), newLock=%d\n",
           pFile->h, pFile->locktype, pFile->sharedLockByte, locktype));





  /* If there is already a lock of this type or more restrictive on the
  ** OsFile, do nothing. Don't use the end_lock: exit path, as
  ** sqlite3OsEnterMutex() hasn't been called yet.
  */
  if( pFile->locktype>=locktype ){
    OSTRACE(("LOCK-HELD file=%p, rc=SQLITE_OK\n", pFile->h));
................................................................................
  int rc;
  winFile *pFile = (winFile*)id;

  SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
  OSTRACE(("TEST-WR-LOCK file=%p, pResOut=%p\n", pFile->h, pResOut));

  assert( id!=0 );



  if( pFile->locktype>=RESERVED_LOCK ){
    rc = 1;
    OSTRACE(("TEST-WR-LOCK file=%p, rc=%d (local)\n", pFile->h, rc));
  }else{
    rc = winLockFile(&pFile->h, SQLITE_LOCKFILEEX_FLAGS,RESERVED_BYTE, 0, 1, 0);
    if( rc ){
      winUnlockFile(&pFile->h, RESERVED_BYTE, 0, 1, 0);
    }
................................................................................
  int type;
  winFile *pFile = (winFile*)id;
  int rc = SQLITE_OK;
  assert( pFile!=0 );
  assert( locktype<=SHARED_LOCK );
  OSTRACE(("UNLOCK file=%p, oldLock=%d(%d), newLock=%d\n",
           pFile->h, pFile->locktype, pFile->sharedLockByte, locktype));




  type = pFile->locktype;
  if( type>=EXCLUSIVE_LOCK ){
    winUnlockFile(&pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
    if( locktype==SHARED_LOCK && !winGetReadLock(pFile) ){
      /* This should never happen.  We should always be able to
      ** reacquire the read lock */
      rc = winLogError(SQLITE_IOERR_UNLOCK, osGetLastError(),
................................................................................
  pFile->h = h;
  if( isReadonly ){
    pFile->ctrlFlags |= WINFILE_RDONLY;
  }
  if( sqlite3_uri_boolean(zName, "psow", SQLITE_POWERSAFE_OVERWRITE) ){
    pFile->ctrlFlags |= WINFILE_PSOW;
  }



  pFile->lastErrno = NO_ERROR;
  pFile->zPath = zName;
#if SQLITE_MAX_MMAP_SIZE>0
  pFile->hMap = NULL;
  pFile->pMapRegion = 0;
  pFile->mmapSize = 0;
  pFile->mmapSizeActual = 0;

Changes to src/pager.c.

622
623
624
625
626
627
628
629

630
631
632
633
634
635
636
....
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
....
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
....
4695
4696
4697
4698
4699
4700
4701

4702
4703
4704
4705
4706
4707
4708
....
4710
4711
4712
4713
4714
4715
4716


4717
4718
4719
4720
4721

4722
4723
4724
4725
4726
4727
4728
  u8 journalMode;             /* One of the PAGER_JOURNALMODE_* values */
  u8 useJournal;              /* Use a rollback journal on this file */
  u8 noSync;                  /* Do not sync the journal if true */
  u8 fullSync;                /* Do extra syncs of the journal for robustness */
  u8 ckptSyncFlags;           /* SYNC_NORMAL or SYNC_FULL for checkpoint */
  u8 walSyncFlags;            /* SYNC_NORMAL or SYNC_FULL for wal writes */
  u8 syncFlags;               /* SYNC_NORMAL or SYNC_FULL otherwise */
  u8 tempFile;                /* zFilename is a temporary file */

  u8 readOnly;                /* True for a read-only database */
  u8 memDb;                   /* True to inhibit all file I/O */

  /**************************************************************************
  ** The following block contains those class members that change during
  ** routine opertion.  Class members not in this block are either fixed
  ** when the pager is first created or else only change when there is a
................................................................................
*/
static int pagerUnlockDb(Pager *pPager, int eLock){
  int rc = SQLITE_OK;

  assert( !pPager->exclusiveMode || pPager->eLock==eLock );
  assert( eLock==NO_LOCK || eLock==SHARED_LOCK );
  assert( eLock!=NO_LOCK || pagerUseWal(pPager)==0 );
  if( isOpen(pPager->fd) && !pPager->tempFile ){
    assert( pPager->eLock>=eLock );
    rc = sqlite3OsUnlock(pPager->fd, eLock);
    if( pPager->eLock!=UNKNOWN_LOCK ){
      pPager->eLock = (u8)eLock;
    }
    IOTRACE(("UNLOCK %p %d\n", pPager, eLock))
  }
  return rc;
}
................................................................................
** of this.
*/
static int pagerLockDb(Pager *pPager, int eLock){
  int rc = SQLITE_OK;

  assert( eLock==SHARED_LOCK || eLock==RESERVED_LOCK || eLock==EXCLUSIVE_LOCK );
  if( pPager->eLock<eLock || pPager->eLock==UNKNOWN_LOCK ){
    rc = sqlite3OsLock(pPager->fd, eLock);
    if( rc==SQLITE_OK && (pPager->eLock!=UNKNOWN_LOCK||eLock==EXCLUSIVE_LOCK) ){
      pPager->eLock = (u8)eLock;
      IOTRACE(("LOCK %p %d\n", pPager, eLock))
    }
  }
  return rc;
}
................................................................................
          for(ii=szPageDflt; ii<=SQLITE_MAX_DEFAULT_PAGE_SIZE; ii=ii*2){
            if( iDc&(SQLITE_IOCAP_ATOMIC|(ii>>8)) ){
              szPageDflt = ii;
            }
          }
        }
#endif

        if( (iDc & SQLITE_IOCAP_IMMUTABLE)!=0
         || sqlite3_uri_boolean(zFilename, "immutable", 0) ){
            vfsFlags |= SQLITE_OPEN_READONLY;
            goto act_like_temp_file;
        }
      }
    }
................................................................................
    /* If a temporary file is requested, it is not opened immediately.
    ** In this case we accept the default page size and delay actually
    ** opening the file until the first call to OsWrite().
    **
    ** This branch is also run for an in-memory database. An in-memory
    ** database is the same as a temp-file that is never written out to
    ** disk and uses an in-memory rollback journal.


    */ 
act_like_temp_file:
    tempFile = 1;
    pPager->eState = PAGER_READER;
    pPager->eLock = EXCLUSIVE_LOCK;

    readOnly = (vfsFlags&SQLITE_OPEN_READONLY);
  }

  /* The following call to PagerSetPagesize() serves to set the value of 
  ** Pager.pageSize and to allocate the Pager.pTmpSpace buffer.
  */
  if( rc==SQLITE_OK ){







|
>







 







|

|







 







|







 







>







 







>
>



|
|
>







622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
....
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
....
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
....
4696
4697
4698
4699
4700
4701
4702
4703
4704
4705
4706
4707
4708
4709
4710
....
4712
4713
4714
4715
4716
4717
4718
4719
4720
4721
4722
4723
4724
4725
4726
4727
4728
4729
4730
4731
4732
4733
  u8 journalMode;             /* One of the PAGER_JOURNALMODE_* values */
  u8 useJournal;              /* Use a rollback journal on this file */
  u8 noSync;                  /* Do not sync the journal if true */
  u8 fullSync;                /* Do extra syncs of the journal for robustness */
  u8 ckptSyncFlags;           /* SYNC_NORMAL or SYNC_FULL for checkpoint */
  u8 walSyncFlags;            /* SYNC_NORMAL or SYNC_FULL for wal writes */
  u8 syncFlags;               /* SYNC_NORMAL or SYNC_FULL otherwise */
  u8 tempFile;                /* zFilename is a temporary or immutable file */
  u8 noLock;                  /* Do not lock (except in WAL mode) */
  u8 readOnly;                /* True for a read-only database */
  u8 memDb;                   /* True to inhibit all file I/O */

  /**************************************************************************
  ** The following block contains those class members that change during
  ** routine opertion.  Class members not in this block are either fixed
  ** when the pager is first created or else only change when there is a
................................................................................
*/
static int pagerUnlockDb(Pager *pPager, int eLock){
  int rc = SQLITE_OK;

  assert( !pPager->exclusiveMode || pPager->eLock==eLock );
  assert( eLock==NO_LOCK || eLock==SHARED_LOCK );
  assert( eLock!=NO_LOCK || pagerUseWal(pPager)==0 );
  if( isOpen(pPager->fd) ){
    assert( pPager->eLock>=eLock );
    rc = pPager->noLock ? SQLITE_OK : sqlite3OsUnlock(pPager->fd, eLock);
    if( pPager->eLock!=UNKNOWN_LOCK ){
      pPager->eLock = (u8)eLock;
    }
    IOTRACE(("UNLOCK %p %d\n", pPager, eLock))
  }
  return rc;
}
................................................................................
** of this.
*/
static int pagerLockDb(Pager *pPager, int eLock){
  int rc = SQLITE_OK;

  assert( eLock==SHARED_LOCK || eLock==RESERVED_LOCK || eLock==EXCLUSIVE_LOCK );
  if( pPager->eLock<eLock || pPager->eLock==UNKNOWN_LOCK ){
    rc = pPager->noLock ? SQLITE_OK : sqlite3OsLock(pPager->fd, eLock);
    if( rc==SQLITE_OK && (pPager->eLock!=UNKNOWN_LOCK||eLock==EXCLUSIVE_LOCK) ){
      pPager->eLock = (u8)eLock;
      IOTRACE(("LOCK %p %d\n", pPager, eLock))
    }
  }
  return rc;
}
................................................................................
          for(ii=szPageDflt; ii<=SQLITE_MAX_DEFAULT_PAGE_SIZE; ii=ii*2){
            if( iDc&(SQLITE_IOCAP_ATOMIC|(ii>>8)) ){
              szPageDflt = ii;
            }
          }
        }
#endif
        pPager->noLock = sqlite3_uri_boolean(zFilename, "nolock", 0);
        if( (iDc & SQLITE_IOCAP_IMMUTABLE)!=0
         || sqlite3_uri_boolean(zFilename, "immutable", 0) ){
            vfsFlags |= SQLITE_OPEN_READONLY;
            goto act_like_temp_file;
        }
      }
    }
................................................................................
    /* If a temporary file is requested, it is not opened immediately.
    ** In this case we accept the default page size and delay actually
    ** opening the file until the first call to OsWrite().
    **
    ** This branch is also run for an in-memory database. An in-memory
    ** database is the same as a temp-file that is never written out to
    ** disk and uses an in-memory rollback journal.
    **
    ** This branch also runs for files marked as immutable.
    */ 
act_like_temp_file:
    tempFile = 1;
    pPager->eState = PAGER_READER;     /* Pretend we already have a lock */
    pPager->eLock = EXCLUSIVE_LOCK;    /* Pretend we are in EXCLUSIVE locking mode */
    pPager->noLock = 1;                /* Do no locking */
    readOnly = (vfsFlags&SQLITE_OPEN_READONLY);
  }

  /* The following call to PagerSetPagesize() serves to set the value of 
  ** Pager.pageSize and to allocate the Pager.pTmpSpace buffer.
  */
  if( rc==SQLITE_OK ){