diff options
Diffstat (limited to 'src/os_unix.c')
| -rw-r--r-- | src/os_unix.c | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/src/os_unix.c b/src/os_unix.c index b2cf9be76..d603caa0d 100644 --- a/src/os_unix.c +++ b/src/os_unix.c @@ -4647,8 +4647,13 @@ shm_open_err: ** Query and/or changes the size of a shared-memory segment. ** The reqSize parameter is the new size of the segment, or -1 to ** do just a query. The size of the segment after resizing is -** written into pNewSize. The start of the shared memory buffer -** is stored in **ppBuffer. +** written into pNewSize. A writer lock is held on the shared memory +** segment while resizing it. +** +** If ppBuffer is not NULL, the a reader lock is acquired no the shared +** memory segment and *ppBuffer is made to point to the start of the +** shared memory segment. xShmRelease() must be called to release the +** lock. */ static int unixShmSize( sqlite3_shm *pSharedMem, /* Pointer returned by unixShmOpen() */ @@ -4680,6 +4685,14 @@ static int unixShmSize( } /* +** Release the lock held on the shared memory segment to that other +** threads are free to resize it if necessary. +*/ +static int unixShmRelease(sqlite3_shm *pSharedMem){ + return SQLITE_OK; +} + +/* ** Create or release a lock on shared memory. */ static int unixShmLock( @@ -5934,6 +5947,7 @@ int sqlite3_os_init(void){ unixGetLastError, /* xGetLastError */ \ unixShmOpen, /* xShmOpen */ \ unixShmSize, /* xShmSize */ \ + unixShmRelease, /* xShmRelease */ \ 0, /* xShmPush */ \ 0, /* xShmPull */ \ unixShmLock, /* xShmLock */ \ |