Index: src/os_unix.c ================================================================== --- src/os_unix.c +++ src/os_unix.c @@ -3571,11 +3571,11 @@ ** If the shared-memory region has already been allocated or is allocated by ** this call as described above, then it is mapped into this processes ** address space (if it is not already), *pp is set to point to the mapped ** memory and SQLITE_OK returned. */ -static int unixShmPage( +static int unixShmMap( sqlite3_file *fd, /* Handle open on database file */ int iRegion, /* Region to retrieve */ int szRegion, /* Size of regions */ int isWrite, /* True to extend file if necessary */ void volatile **pp /* OUT: Mapped memory */ @@ -3653,11 +3653,11 @@ #else # define unixShmOpen 0 # define unixShmLock 0 # define unixShmBarrier 0 # define unixShmClose 0 -# define unixShmPage 0 +# define unixShmMap 0 #endif /* #ifndef SQLITE_OMIT_WAL */ /* ** Here ends the implementation of all sqlite3_file methods. ** @@ -3715,11 +3715,11 @@ unixDeviceCharacteristics, /* xDeviceCapabilities */ \ unixShmOpen, /* xShmOpen */ \ unixShmLock, /* xShmLock */ \ unixShmBarrier, /* xShmBarrier */ \ unixShmClose, /* xShmClose */ \ - unixShmPage /* xShmPage */ \ + unixShmMap /* xShmMap */ \ }; \ static const sqlite3_io_methods *FINDER##Impl(const char *z, unixFile *p){ \ UNUSED_PARAMETER(z); UNUSED_PARAMETER(p); \ return &METHOD; \ } \ Index: src/os_win.c ================================================================== --- src/os_win.c +++ src/os_win.c @@ -1214,17 +1214,21 @@ ** sqlite3_mutex_notheld() on mutex whenever mutexBuf is acquired or ** released. */ struct winShmNode { sqlite3_mutex *mutex; /* Mutex to access this object */ - sqlite3_mutex *mutexBuf; /* Mutex to access zBuf[] */ char *zFilename; /* Name of the file */ winFile hFile; /* File handle from winOpen */ - HANDLE hMap; /* File handle from CreateFileMapping */ + + int szRegion; /* Size of shared-memory regions */ + int nRegion; /* Size of array apRegion */ + struct ShmRegion { + HANDLE hMap; /* File handle from CreateFileMapping */ + void *pMap; + } *aRegion; DWORD lastErrno; /* The Windows errno from the last I/O error */ - int szMap; /* Size of the mapping of file into memory */ - char *pMMapBuf; /* Where currently mmapped(). NULL if unmapped */ + int nRef; /* Number of winShm objects pointing to this */ winShm *pFirst; /* All winShm objects pointing to this */ winShmNode *pNext; /* Next in list of all winShmNode objects */ #ifdef SQLITE_DEBUG u8 nextShmId; /* Next available winShm.id value */ @@ -1323,23 +1327,22 @@ winShmNode *p; assert( winShmMutexHeld() ); pp = &winShmNodeList; while( (p = *pp)!=0 ){ if( p->nRef==0 ){ + int i; if( p->mutex ) sqlite3_mutex_free(p->mutex); - if( p->mutexBuf ) sqlite3_mutex_free(p->mutexBuf); - if( p->pMMapBuf ){ - UnmapViewOfFile(p->pMMapBuf); - } - if( INVALID_HANDLE_VALUE != p->hMap ){ - CloseHandle(p->hMap); + for(i=0; inRegion; i++){ + UnmapViewOfFile(p->aRegion[i].pMap); + CloseHandle(p->aRegion[i].hMap); } if( p->hFile.h != INVALID_HANDLE_VALUE ) { winClose((sqlite3_file *)&p->hFile); } if( deleteFlag ) winDelete(pVfs, p->zFilename, 0); *pp = p->pNext; + sqlite3_free(p->aRegion); sqlite3_free(p); }else{ pp = &p->pNext; } } @@ -1402,24 +1405,17 @@ if( pShmNode ){ sqlite3_free(pNew); }else{ pShmNode = pNew; pNew = 0; - pShmNode->pMMapBuf = NULL; - pShmNode->hMap = INVALID_HANDLE_VALUE; ((winFile*)(&pShmNode->hFile))->h = INVALID_HANDLE_VALUE; pShmNode->pNext = winShmNodeList; winShmNodeList = pShmNode; pShmNode->mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_FAST); if( pShmNode->mutex==0 ){ rc = SQLITE_NOMEM; - goto shm_open_err; - } - pShmNode->mutexBuf = sqlite3_mutex_alloc(SQLITE_MUTEX_FAST); - if( pShmNode->mutexBuf==0 ){ - rc = SQLITE_NOMEM; goto shm_open_err; } rc = winOpen(pDbFd->pVfs, pShmNode->zFilename, /* Name of the file (UTF-8) */ (sqlite3_file*)&pShmNode->hFile, /* File handle here */ @@ -1505,177 +1501,119 @@ return SQLITE_OK; } /* -** Increase the size of the underlying storage for a shared-memory segment. +** This function is called to obtain a pointer to region iRegion of the +** shared-memory associated with the database file fd. Shared-memory regions +** are numbered starting from zero. Each shared-memory region is szRegion +** bytes in size. +** +** If an error occurs, an error code is returned and *pp is set to NULL. ** -** The reqSize parameter is the new requested minimum size of the underlying -** shared memory. This routine may choose to make the shared memory larger -** than this value (for example to round the shared memory size up to an -** operating-system dependent page size.) +** Otherwise, if the isWrite parameter is 0 and the requested shared-memory +** region has not been allocated (by any client, including one running in a +** separate process), then *pp is set to NULL and SQLITE_OK returned. If +** isWrite is non-zero and the requested shared-memory region has not yet +** been allocated, it is allocated by this function. ** -** This routine will only grow the size of shared memory. A request for -** a smaller size is a no-op. -*/ -static int winShmSize( - sqlite3_file *fd, /* Database holding the shared memory */ - int reqSize, /* Requested size. -1 for query only */ - int *pNewSize /* Write new size here */ -){ - winFile *pDbFd = (winFile*)fd; - winShm *p = pDbFd->pShm; - winShmNode *pShmNode = p->pShmNode; - int rc = SQLITE_OK; - - *pNewSize = 0; - if( reqSize>=0 ){ - sqlite3_int64 sz; - rc = winFileSize((sqlite3_file *)&pShmNode->hFile, &sz); - if( SQLITE_OK==rc && reqSize>sz ){ - rc = winTruncate((sqlite3_file *)&pShmNode->hFile, reqSize); - } - } - if( SQLITE_OK==rc ){ - sqlite3_int64 sz; - rc = winFileSize((sqlite3_file *)&pShmNode->hFile, &sz); - if( SQLITE_OK==rc ){ - *pNewSize = (int)sz; - }else{ - rc = SQLITE_IOERR; - } - } - return rc; -} - - -/* -** Map the shared storage into memory. The minimum size of the -** mapping should be reqMapSize if reqMapSize is positive. If -** reqMapSize is zero or negative, the implementation can choose -** whatever mapping size is convenient. -** -** *ppBuf is made to point to the memory which is a mapping of the -** underlying storage. A mutex is acquired to prevent other threads -** from running while *ppBuf is in use in order to prevent other threads -** remapping *ppBuf out from under this thread. The winShmRelease() -** call will release the mutex. However, if the lock state is CHECKPOINT, -** the mutex is not acquired because CHECKPOINT will never remap the -** buffer. RECOVER might remap, though, so CHECKPOINT will acquire -** the mutex if and when it promotes to RECOVER. -** -** RECOVER needs to be atomic. The same mutex that prevents *ppBuf from -** being remapped also prevents more than one thread from being in -** RECOVER at a time. But, RECOVER sometimes wants to remap itself. -** To prevent RECOVER from losing its lock while remapping, the -** mutex is not released by winShmRelease() when in RECOVER. -** -** *pNewMapSize is set to the size of the mapping. -** -** *ppBuf and *pNewMapSize might be NULL and zero if no space has -** yet been allocated to the underlying storage. -*/ -static int winShmGet( - sqlite3_file *fd, /* The database file holding the shared memory */ - int reqMapSize, /* Requested size of mapping. -1 means don't care */ - int *pNewMapSize, /* Write new size of mapping here */ - void volatile **ppBuf /* Write mapping buffer origin here */ +** If the shared-memory region has already been allocated or is allocated by +** this call as described above, then it is mapped into this processes +** address space (if it is not already), *pp is set to point to the mapped +** memory and SQLITE_OK returned. +*/ +static int winShmMap( + sqlite3_file *fd, /* Handle open on database file */ + int iRegion, /* Region to retrieve */ + int szRegion, /* Size of regions */ + int isWrite, /* True to extend file if necessary */ + void volatile **pp /* OUT: Mapped memory */ ){ winFile *pDbFd = (winFile*)fd; winShm *p = pDbFd->pShm; winShmNode *pShmNode = p->pShmNode; int rc = SQLITE_OK; - if( p->hasMutexBuf==0 ){ - assert( sqlite3_mutex_notheld(pShmNode->mutex) ); - sqlite3_mutex_enter(pShmNode->mutexBuf); - p->hasMutexBuf = 1; - } sqlite3_mutex_enter(pShmNode->mutex); - if( pShmNode->szMap==0 || reqMapSize>pShmNode->szMap ){ - int actualSize; - if( winShmSize(fd, -1, &actualSize)==SQLITE_OK - && reqMapSizepMMapBuf ){ - if( !UnmapViewOfFile(pShmNode->pMMapBuf) ){ + assert( szRegion==pShmNode->szRegion || pShmNode->nRegion==0 ); + + if( pShmNode->nRegion<=iRegion ){ + struct ShmRegion *apNew; /* New aRegion[] array */ + int nByte = (iRegion+1)*szRegion; /* Minimum required file size */ + sqlite3_int64 sz; /* Current size of wal-index file */ + + pShmNode->szRegion = szRegion; + + /* The requested region is not mapped into this processes address space. + ** Check to see if it has been allocated (i.e. if the wal-index file is + ** large enough to contain the requested region). + */ + rc = winFileSize((sqlite3_file *)&pShmNode->hFile, &sz); + if( rc!=SQLITE_OK ){ + goto shmpage_out; + } + + if( szhFile, nByte); + if( rc!=SQLITE_OK ){ + goto shmpage_out; + } + } + + /* Map the requested memory region into this processes address space. */ + apNew = (struct ShmRegion *)sqlite3_realloc( + pShmNode->aRegion, (iRegion+1)*sizeof(apNew[0]) + ); + if( !apNew ){ + rc = SQLITE_IOERR_NOMEM; + goto shmpage_out; + } + pShmNode->aRegion = apNew; + + while( pShmNode->nRegion<=iRegion ){ + HANDLE hMap; /* file-mapping handle */ + void *pMap = 0; /* Mapped memory region */ + + hMap = CreateFileMapping(pShmNode->hFile.h, + NULL, PAGE_READWRITE, 0, nByte, NULL + ); + if( hMap ){ + pMap = MapViewOfFile(hMap, FILE_MAP_WRITE | FILE_MAP_READ, + 0, 0, nByte + ); + } + if( !pMap ){ pShmNode->lastErrno = GetLastError(); rc = SQLITE_IOERR; + if( hMap ) CloseHandle(hMap); + goto shmpage_out; } - CloseHandle(pShmNode->hMap); - pShmNode->hMap = INVALID_HANDLE_VALUE; - } - if( SQLITE_OK == rc ){ - pShmNode->pMMapBuf = 0; - if( reqMapSize == 0 ){ - /* can't create 0 byte file mapping in Windows */ - pShmNode->szMap = 0; - }else{ - /* create the file mapping object */ - if( INVALID_HANDLE_VALUE == pShmNode->hMap ){ - /* TBD provide an object name to each file - ** mapping so it can be re-used across processes. - */ - pShmNode->hMap = CreateFileMapping(pShmNode->hFile.h, - NULL, - PAGE_READWRITE, - 0, - reqMapSize, - NULL); - } - if( NULL==pShmNode->hMap ){ - pShmNode->lastErrno = GetLastError(); - rc = SQLITE_IOERR; - pShmNode->szMap = 0; - pShmNode->hMap = INVALID_HANDLE_VALUE; - }else{ - pShmNode->pMMapBuf = MapViewOfFile(pShmNode->hMap, - FILE_MAP_WRITE | FILE_MAP_READ, - 0, - 0, - reqMapSize); - if( !pShmNode->pMMapBuf ){ - pShmNode->lastErrno = GetLastError(); - rc = SQLITE_IOERR; - pShmNode->szMap = 0; - }else{ - pShmNode->szMap = reqMapSize; - } - } - } - } - } - *pNewMapSize = pShmNode->szMap; - *ppBuf = pShmNode->pMMapBuf; + + pShmNode->aRegion[pShmNode->nRegion].pMap = pMap; + pShmNode->aRegion[pShmNode->nRegion].hMap = hMap; + pShmNode->nRegion++; + } + } + +shmpage_out: + if( pShmNode->nRegion>iRegion ){ + char *p = (char *)pShmNode->aRegion[iRegion].pMap; + *pp = (void *)&p[iRegion*szRegion]; + }else{ + *pp = 0; + } sqlite3_mutex_leave(pShmNode->mutex); return rc; } -/* -** Release the lock held on the shared memory segment so that other -** threads are free to resize it if necessary. -** -** If the lock is not currently held, this routine is a harmless no-op. -** -** If the shared-memory object is in lock state RECOVER, then we do not -** really want to release the lock, so in that case too, this routine -** is a no-op. -*/ -static int winShmRelease(sqlite3_file *fd){ - winFile *pDbFd = (winFile*)fd; - winShm *p = pDbFd->pShm; - if( p->hasMutexBuf ){ - winShmNode *pShmNode = p->pShmNode; - assert( sqlite3_mutex_notheld(pShmNode->mutex) ); - sqlite3_mutex_leave(pShmNode->mutexBuf); - p->hasMutexBuf = 0; - } - return SQLITE_OK; -} - /* ** Change the lock state for a shared-memory segment. */ static int winShmLock( sqlite3_file *fd, /* Database file holding the shared memory */ @@ -1754,16 +1692,14 @@ winCheckReservedLock, winFileControl, winSectorSize, winDeviceCharacteristics, winShmOpen, /* xShmOpen */ - winShmSize, /* xShmSize */ - winShmGet, /* xShmGet */ - winShmRelease, /* xShmRelease */ winShmLock, /* xShmLock */ winShmBarrier, /* xShmBarrier */ - winShmClose /* xShmClose */ + winShmClose, /* xShmClose */ + winShmMap /* xShmMap */ }; /*************************************************************************** ** Here ends the I/O methods that form the sqlite3_io_methods object. **