/* ** 2004 May 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. ** ****************************************************************************** ** ** This file contains code that is specific to windows. */ #include "sqliteInt.h" #if SQLITE_OS_WIN /* This file is used for windows only */ /* ** A Note About Memory Allocation: ** ** This driver uses malloc()/free() directly rather than going through ** the SQLite-wrappers sqlite3_malloc()/sqlite3_free(). Those wrappers ** are designed for use on embedded systems where memory is scarce and ** malloc failures happen frequently. Win32 does not typically run on ** embedded systems, and when it does the developers normally have bigger ** problems to worry about than running out of memory. So there is not ** a compelling need to use the wrappers. ** ** But there is a good reason to not use the wrappers. If we use the ** wrappers then we will get simulated malloc() failures within this ** driver. And that causes all kinds of problems for our tests. We ** could enhance SQLite to deal with simulated malloc failures within ** the OS driver, but the code to deal with those failure would not ** be exercised on Linux (which does not need to malloc() in the driver) ** and so we would have difficulty writing coverage tests for that ** code. Better to leave the code out, we think. ** ** The point of this discussion is as follows: When creating a new ** OS layer for an embedded system, if you use this file as an example, ** avoid the use of malloc()/free(). Those routines work ok on windows ** desktops but not so well in embedded systems. */ #include #ifdef __CYGWIN__ # include #endif /* ** Macros used to determine whether or not to use threads. */ #if defined(THREADSAFE) && THREADSAFE # define SQLITE_W32_THREADS 1 #endif /* ** Include code that is common to all os_*.c files */ #include "os_common.h" /* ** Some microsoft compilers lack this definition. */ #ifndef INVALID_FILE_ATTRIBUTES # define INVALID_FILE_ATTRIBUTES ((DWORD)-1) #endif /* ** Determine if we are dealing with WindowsCE - which has a much ** reduced API. */ #if SQLITE_OS_WINCE # define AreFileApisANSI() 1 # define FormatMessageW(a,b,c,d,e,f,g) 0 #endif /* Forward references */ typedef struct winShm winShm; /* A connection to shared-memory */ typedef struct winShmNode winShmNode; /* A region of shared-memory */ /* ** WinCE lacks native support for file locking so we have to fake it ** with some code of our own. */ #if SQLITE_OS_WINCE typedef struct winceLock { int nReaders; /* Number of reader locks obtained */ BOOL bPending; /* Indicates a pending lock has been obtained */ BOOL bReserved; /* Indicates a reserved lock has been obtained */ BOOL bExclusive; /* Indicates an exclusive lock has been obtained */ } winceLock; #endif /* ** The winFile structure is a subclass of sqlite3_file* specific to the win32 ** portability layer. */ typedef struct winFile winFile; struct winFile { const sqlite3_io_methods *pMethod; /*** Must be first ***/ sqlite3_vfs *pVfs; /* The VFS used to open this file */ HANDLE h; /* Handle for accessing the file */ u8 locktype; /* Type of lock currently held on this file */ short sharedLockByte; /* Randomly chosen byte used as a shared lock */ u8 bPersistWal; /* True to persist WAL files */ DWORD lastErrno; /* The Windows errno from the last I/O error */ DWORD sectorSize; /* Sector size of the device file is on */ winShm *pShm; /* Instance of shared memory on this file */ const char *zPath; /* Full pathname of this file */ int szChunk; /* Chunk size configured by FCNTL_CHUNK_SIZE */ #if SQLITE_OS_WINCE WCHAR *zDeleteOnClose; /* Name of file to delete when closing */ HANDLE hMutex; /* Mutex used to control access to shared lock */ HANDLE hShared; /* Shared memory segment used for locking */ winceLock local; /* Locks obtained by this instance of winFile */ winceLock *shared; /* Global shared lock memory for the file */ #endif }; /* * If compiled with SQLITE_WIN32_MALLOC on Windows, we will use the * various Win32 API heap functions instead of our own. */ #ifdef SQLITE_WIN32_MALLOC /* * The initial size of the Win32-specific heap. This value may be zero. */ #ifndef SQLITE_WIN32_HEAP_INIT_SIZE # define SQLITE_WIN32_HEAP_INIT_SIZE ((SQLITE_DEFAULT_CACHE_SIZE) * \ (SQLITE_DEFAULT_PAGE_SIZE) + 4194304) #endif /* * The maximum size of the Win32-specific heap. This value may be zero. */ #ifndef SQLITE_WIN32_HEAP_MAX_SIZE # define SQLITE_WIN32_HEAP_MAX_SIZE (0) #endif /* ** The winMemData structure stores information required by the Win32-specific ** sqlite3_mem_methods implementation. */ typedef struct winMemData winMemData; struct winMemData { u32 magic; /* Magic number to detect structure corruption. */ HANDLE hHeap; /* The handle to our heap. */ BOOL bOwned; /* Do we own the heap (i.e. destroy it on shutdown)? */ }; #define WINMEM_MAGIC 0x42b2830b static struct winMemData win_mem_data = { WINMEM_MAGIC, NULL, FALSE }; #define winMemAssertMagic() assert( win_mem_data.magic==WINMEM_MAGIC ) #define winMemGetHeap() win_mem_data.hHeap static void *winMemMalloc(int nBytes); static void winMemFree(void *pPrior); static void *winMemRealloc(void *pPrior, int nBytes); static int winMemSize(void *p); static int winMemRoundup(int n); static int winMemInit(void *pAppData); static void winMemShutdown(void *pAppData); const sqlite3_mem_methods *sqlite3MemGetWin32(void); #endif /* SQLITE_WIN32_MALLOC */ /* ** Forward prototypes. */ static int getSectorSize( sqlite3_vfs *pVfs, const char *zRelative /* UTF-8 file name */ ); /* ** The following variable is (normally) set once and never changes ** thereafter. It records whether the operating system is Win95 ** or WinNT. ** ** 0: Operating system unknown. ** 1: Operating system is Win95. ** 2: Operating system is WinNT. ** ** In order to facilitate testing on a WinNT system, the test fixture ** can manually set this value to 1 to emulate Win98 behavior. */ #ifdef SQLITE_TEST int sqlite3_os_type = 0; #else static int sqlite3_os_type = 0; #endif /* ** Return true (non-zero) if we are running under WinNT, Win2K, WinXP, ** or WinCE. Return false (zero) for Win95, Win98, or WinME. ** ** Here is an interesting observation: Win95, Win98, and WinME lack ** the LockFileEx() API. But we can still statically link against that ** API as long as we don't call it when running Win95/98/ME. A call to ** this routine is used to determine if the host is Win95/98/ME or ** WinNT/2K/XP so that we will know whether or not we can safely call ** the LockFileEx() API. */ #if SQLITE_OS_WINCE # define isNT() (1) #else static int isNT(void){ if( sqlite3_os_type==0 ){ OSVERSIONINFO sInfo; sInfo.dwOSVersionInfoSize = sizeof(sInfo); GetVersionEx(&sInfo); sqlite3_os_type = sInfo.dwPlatformId==VER_PLATFORM_WIN32_NT ? 2 : 1; } return sqlite3_os_type==2; } #endif /* SQLITE_OS_WINCE */ #ifdef SQLITE_WIN32_MALLOC /* ** Allocate nBytes of memory. */ static void *winMemMalloc(int nBytes){ HANDLE hHeap; void *p; winMemAssertMagic(); hHeap = winMemGetHeap(); assert( hHeap!=0 ); assert( hHeap!=INVALID_HANDLE_VALUE ); #ifdef SQLITE_WIN32_MALLOC_VALIDATE assert ( HeapValidate(hHeap, 0, NULL) ); #endif assert( nBytes>=0 ); p = HeapAlloc(hHeap, 0, (SIZE_T)nBytes); if( !p ){ sqlite3_log(SQLITE_NOMEM, "failed to HeapAlloc %u bytes (%d), heap=%p", nBytes, GetLastError(), (void*)hHeap); } return p; } /* ** Free memory. */ static void winMemFree(void *pPrior){ HANDLE hHeap; winMemAssertMagic(); hHeap = winMemGetHeap(); assert( hHeap!=0 ); assert( hHeap!=INVALID_HANDLE_VALUE ); #ifdef SQLITE_WIN32_MALLOC_VALIDATE assert ( HeapValidate(hHeap, 0, pPrior) ); #endif if( !pPrior ) return; /* Passing NULL to HeapFree is undefined. */ if( !HeapFree(hHeap, 0, pPrior) ){ sqlite3_log(SQLITE_NOMEM, "failed to HeapFree block %p (%d), heap=%p", pPrior, GetLastError(), (void*)hHeap); } } /* ** Change the size of an existing memory allocation */ static void *winMemRealloc(void *pPrior, int nBytes){ HANDLE hHeap; void *p; winMemAssertMagic(); hHeap = winMemGetHeap(); assert( hHeap!=0 ); assert( hHeap!=INVALID_HANDLE_VALUE ); #ifdef SQLITE_WIN32_MALLOC_VALIDATE assert ( HeapValidate(hHeap, 0, pPrior) ); #endif assert( nBytes>=0 ); if( !pPrior ){ p = HeapAlloc(hHeap, 0, (SIZE_T)nBytes); }else{ p = HeapReAlloc(hHeap, 0, pPrior, (SIZE_T)nBytes); } if( !p ){ sqlite3_log(SQLITE_NOMEM, "failed to %s %u bytes (%d), heap=%p", pPrior ? "HeapReAlloc" : "HeapAlloc", nBytes, GetLastError(), (void*)hHeap); } return p; } /* ** Return the size of an outstanding allocation, in bytes. */ static int winMemSize(void *p){ HANDLE hHeap; SIZE_T n; winMemAssertMagic(); hHeap = winMemGetHeap(); assert( hHeap!=0 ); assert( hHeap!=INVALID_HANDLE_VALUE ); #ifdef SQLITE_WIN32_MALLOC_VALIDATE assert ( HeapValidate(hHeap, 0, NULL) ); #endif if( !p ) return 0; n = HeapSize(hHeap, 0, p); if( n==(SIZE_T)-1 ){ sqlite3_log(SQLITE_NOMEM, "failed to HeapSize block %p (%d), heap=%p", p, GetLastError(), (void*)hHeap); return 0; } return (int)n; } /* ** Round up a request size to the next valid allocation size. */ static int winMemRoundup(int n){ return n; } /* ** Initialize this module. */ static int winMemInit(void *pAppData){ winMemData *pWinMemData = (winMemData *)pAppData; if( !pWinMemData ) return SQLITE_ERROR; assert( pWinMemData->magic==WINMEM_MAGIC ); if( !pWinMemData->hHeap ){ pWinMemData->hHeap = HeapCreate(0, SQLITE_WIN32_HEAP_INIT_SIZE, SQLITE_WIN32_HEAP_MAX_SIZE); if( !pWinMemData->hHeap ){ sqlite3_log(SQLITE_NOMEM, "failed to HeapCreate (%d), initSize=%u, maxSize=%u", GetLastError(), SQLITE_WIN32_HEAP_INIT_SIZE, SQLITE_WIN32_HEAP_MAX_SIZE); return SQLITE_NOMEM; } pWinMemData->bOwned = TRUE; } assert( pWinMemData->hHeap!=0 ); assert( pWinMemData->hHeap!=INVALID_HANDLE_VALUE ); #ifdef SQLITE_WIN32_MALLOC_VALIDATE assert( HeapValidate(pWinMemData->hHeap, 0, NULL) ); #endif return SQLITE_OK; } /* ** Deinitialize this module. */ static void winMemShutdown(void *pAppData){ winMemData *pWinMemData = (winMemData *)pAppData; if( !pWinMemData ) return; if( pWinMemData->hHeap ){ assert( pWinMemData->hHeap!=INVALID_HANDLE_VALUE ); #ifdef SQLITE_WIN32_MALLOC_VALIDATE assert( HeapValidate(pWinMemData->hHeap, 0, NULL) ); #endif if( pWinMemData->bOwned ){ if( !HeapDestroy(pWinMemData->hHeap) ){ sqlite3_log(SQLITE_NOMEM, "failed to HeapDestroy (%d), heap=%p", GetLastError(), (void*)pWinMemData->hHeap); } pWinMemData->bOwned = FALSE; } pWinMemData->hHeap = NULL; } } /* ** Populate the low-level memory allocation function pointers in ** sqlite3GlobalConfig.m with pointers to the routines in this file. The ** arguments specify the block of memory to manage. ** ** This routine is only called by sqlite3_config(), and therefore ** is not required to be threadsafe (it is not). */ const sqlite3_mem_methods *sqlite3MemGetWin32(void){ static const sqlite3_mem_methods winMemMethods = { winMemMalloc, winMemFree, winMemRealloc, winMemSize, winMemRoundup, winMemInit, winMemShutdown, &win_mem_data }; return &winMemMethods; } void sqlite3MemSetDefault(void){ sqlite3_config(SQLITE_CONFIG_MALLOC, sqlite3MemGetWin32()); } #endif /* SQLITE_WIN32_MALLOC */ /* ** Convert a UTF-8 string to microsoft unicode (UTF-16?). ** ** Space to hold the returned string is obtained from malloc. */ static WCHAR *utf8ToUnicode(const char *zFilename){ int nChar; WCHAR *zWideFilename; nChar = MultiByteToWideChar(CP_UTF8, 0, zFilename, -1, NULL, 0); zWideFilename = malloc( nChar*sizeof(zWideFilename[0]) ); if( zWideFilename==0 ){ return 0; } nChar = MultiByteToWideChar(CP_UTF8, 0, zFilename, -1, zWideFilename, nChar); if( nChar==0 ){ free(zWideFilename); zWideFilename = 0; } return zWideFilename; } /* ** Convert microsoft unicode to UTF-8. Space to hold the returned string is ** obtained from malloc(). */ static char *unicodeToUtf8(const WCHAR *zWideFilename){ int nByte; char *zFilename; nByte = WideCharToMultiByte(CP_UTF8, 0, zWideFilename, -1, 0, 0, 0, 0); zFilename = malloc( nByte ); if( zFilename==0 ){ return 0; } nByte = WideCharToMultiByte(CP_UTF8, 0, zWideFilename, -1, zFilename, nByte, 0, 0); if( nByte == 0 ){ free(zFilename); zFilename = 0; } return zFilename; } /* ** Convert an ansi string to microsoft unicode, based on the ** current codepage settings for file apis. ** ** Space to hold the returned string is obtained ** from malloc. */ static WCHAR *mbcsToUnicode(const char *zFilename){ int nByte; WCHAR *zMbcsFilename; int codepage = AreFileApisANSI() ? CP_ACP : CP_OEMCP; nByte = MultiByteToWideChar(codepage, 0, zFilename, -1, NULL,0)*sizeof(WCHAR); zMbcsFilename = malloc( nByte*sizeof(zMbcsFilename[0]) ); if( zMbcsFilename==0 ){ return 0; } nByte = MultiByteToWideChar(codepage, 0, zFilename, -1, zMbcsFilename, nByte); if( nByte==0 ){ free(zMbcsFilename); zMbcsFilename = 0; } return zMbcsFilename; } /* ** Convert microsoft unicode to multibyte character string, based on the ** user's Ansi codepage. ** ** Space to hold the returned string is obtained from ** malloc(). */ static char *unicodeToMbcs(const WCHAR *zWideFilename){ int nByte; char *zFilename; int codepage = AreFileApisANSI() ? CP_ACP : CP_OEMCP; nByte = WideCharToMultiByte(codepage, 0, zWideFilename, -1, 0, 0, 0, 0); zFilename = malloc( nByte ); if( zFilename==0 ){ return 0; } nByte = WideCharToMultiByte(codepage, 0, zWideFilename, -1, zFilename, nByte, 0, 0); if( nByte == 0 ){ free(zFilename); zFilename = 0; } return zFilename; } /* ** Convert multibyte character string to UTF-8. Space to hold the ** returned string is obtained from malloc(). */ char *sqlite3_win32_mbcs_to_utf8(const char *zFilename){ char *zFilenameUtf8; WCHAR *zTmpWide; zTmpWide = mbcsToUnicode(zFilename); if( zTmpWide==0 ){ return 0; } zFilenameUtf8 = unicodeToUtf8(zTmpWide); free(zTmpWide); return zFilenameUtf8; } /* ** Convert UTF-8 to multibyte character string. Space to hold the ** returned string is obtained from malloc(). */ char *sqlite3_win32_utf8_to_mbcs(const char *zFilename){ char *zFilenameMbcs; WCHAR *zTmpWide; zTmpWide = utf8ToUnicode(zFilename); if( zTmpWide==0 ){ return 0; } zFilenameMbcs = unicodeToMbcs(zTmpWide); free(zTmpWide); return zFilenameMbcs; } /* ** The return value of getLastErrorMsg ** is zero if the error message fits in the buffer, or non-zero ** otherwise (if the message was truncated). */ static int getLastErrorMsg(int nBuf, char *zBuf){ /* FormatMessage returns 0 on failure. Otherwise it ** returns the number of TCHARs written to the output ** buffer, excluding the terminating null char. */ DWORD error = GetLastError(); DWORD dwLen = 0; char *zOut = 0; if( isNT() ){ WCHAR *zTempWide = NULL; dwLen = FormatMessageW(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, NULL, error, 0, (LPWSTR) &zTempWide, 0, 0); if( dwLen > 0 ){ /* allocate a buffer and convert to UTF8 */ zOut = unicodeToUtf8(zTempWide); /* free the system buffer allocated by FormatMessage */ LocalFree(zTempWide); } /* isNT() is 1 if SQLITE_OS_WINCE==1, so this else is never executed. ** Since the ASCII version of these Windows API do not exist for WINCE, ** it's important to not reference them for WINCE builds. */ #if SQLITE_OS_WINCE==0 }else{ char *zTemp = NULL; dwLen = FormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, NULL, error, 0, (LPSTR) &zTemp, 0, 0); if( dwLen > 0 ){ /* allocate a buffer and convert to UTF8 */ zOut = sqlite3_win32_mbcs_to_utf8(zTemp); /* free the system buffer allocated by FormatMessage */ LocalFree(zTemp); } #endif } if( 0 == dwLen ){ sqlite3_snprintf(nBuf, zBuf, "OsError 0x%x (%u)", error, error); }else{ /* copy a maximum of nBuf chars to output buffer */ sqlite3_snprintf(nBuf, zBuf, "%s", zOut); /* free the UTF8 buffer */ free(zOut); } return 0; } /* ** ** This function - winLogErrorAtLine() - is only ever called via the macro ** winLogError(). ** ** This routine is invoked after an error occurs in an OS function. ** It logs a message using sqlite3_log() containing the current value of ** error code and, if possible, the human-readable equivalent from ** FormatMessage. ** ** The first argument passed to the macro should be the error code that ** will be returned to SQLite (e.g. SQLITE_IOERR_DELETE, SQLITE_CANTOPEN). ** The two subsequent arguments should be the name of the OS function that ** failed and the the associated file-system path, if any. */ #define winLogError(a,b,c) winLogErrorAtLine(a,b,c,__LINE__) static int winLogErrorAtLine( int errcode, /* SQLite error code */ const char *zFunc, /* Name of OS function that failed */ const char *zPath, /* File path associated with error */ int iLine /* Source line number where error occurred */ ){ char zMsg[500]; /* Human readable error text */ int i; /* Loop counter */ DWORD iErrno = GetLastError(); /* Error code */ zMsg[0] = 0; getLastErrorMsg(sizeof(zMsg), zMsg); assert( errcode!=SQLITE_OK ); if( zPath==0 ) zPath = ""; for(i=0; zMsg[i] && zMsg[i]!='\r' && zMsg[i]!='\n'; i++){} zMsg[i] = 0; sqlite3_log(errcode, "os_win.c:%d: (%d) %s(%s) - %s", iLine, iErrno, zFunc, zPath, zMsg ); return errcode; } /* ** The number of times that a ReadFile(), WriteFile(), and DeleteFile() ** will be retried following a locking error - probably caused by ** antivirus software. Also the initial delay before the first retry. ** The delay increases linearly with each retry. */ #ifndef SQLITE_WIN32_IOERR_RETRY # define SQLITE_WIN32_IOERR_RETRY 10 #endif #ifndef SQLITE_WIN32_IOERR_RETRY_DELAY # define SQLITE_WIN32_IOERR_RETRY_DELAY 25 #endif static int win32IoerrRetry = SQLITE_WIN32_IOERR_RETRY; static int win32IoerrRetryDelay = SQLITE_WIN32_IOERR_RETRY_DELAY; /* ** If a ReadFile() or WriteFile() error occurs, invoke this routine ** to see if it should be retried. Return TRUE to retry. Return FALSE ** to give up with an error. */ static int retryIoerr(int *pnRetry){ DWORD e; if( *pnRetry>=win32IoerrRetry ){ return 0; } e = GetLastError(); if( e==ERROR_ACCESS_DENIED || e==ERROR_LOCK_VIOLATION || e==ERROR_SHARING_VIOLATION ){ Sleep(win32IoerrRetryDelay*(1+*pnRetry)); ++*pnRetry; return 1; } return 0; } /* ** Log a I/O error retry episode. */ static void logIoerr(int nRetry){ if( nRetry ){ sqlite3_log(SQLITE_IOERR, "delayed %dms for lock/sharing conflict", win32IoerrRetryDelay*nRetry*(nRetry+1)/2 ); } } #if SQLITE_OS_WINCE /************************************************************************* ** This section contains code for WinCE only. */ /* ** WindowsCE does not have a localtime() function. So create a ** substitute. */ #include struct tm *__cdecl localtime(const time_t *t) { static struct tm y; FILETIME uTm, lTm; SYSTEMTIME pTm; sqlite3_int64 t64; t64 = *t; t64 = (t64 + 11644473600)*10000000; uTm.dwLowDateTime = (DWORD)(t64 & 0xFFFFFFFF); uTm.dwHighDateTime= (DWORD)(t64 >> 32); FileTimeToLocalFileTime(&uTm,&lTm); FileTimeToSystemTime(&lTm,&pTm); y.tm_year = pTm.wYear - 1900; y.tm_mon = pTm.wMonth - 1; y.tm_wday = pTm.wDayOfWeek; y.tm_mday = pTm.wDay; y.tm_hour = pTm.wHour; y.tm_min = pTm.wMinute; y.tm_sec = pTm.wSecond; return &y; } /* This will never be called, but defined to make the code compile */ #define GetTempPathA(a,b) #define LockFile(a,b,c,d,e) winceLockFile(&a, b, c, d, e) #define UnlockFile(a,b,c,d,e) winceUnlockFile(&a, b, c, d, e) #define LockFileEx(a,b,c,d,e,f) winceLockFileEx(&a, b, c, d, e, f) #define HANDLE_TO_WINFILE(a) (winFile*)&((char*)a)[-(int)offsetof(winFile,h)] /* ** Acquire a lock on the handle h */ static void winceMutexAcquire(HANDLE h){ DWORD dwErr; do { dwErr = WaitForSingleObject(h, INFINITE); } while (dwErr != WAIT_OBJECT_0 && dwErr != WAIT_ABANDONED); } /* ** Release a lock acquired by winceMutexAcquire() */ #define winceMutexRelease(h) ReleaseMutex(h) /* ** Create the mutex and shared memory used for locking in the file ** descriptor pFile */ static BOOL winceCreateLock(const char *zFilename, winFile *pFile){ WCHAR *zTok; WCHAR *zName = utf8ToUnicode(zFilename); BOOL bInit = TRUE; /* Initialize the local lockdata */ ZeroMemory(&pFile->local, sizeof(pFile->local)); /* Replace the backslashes from the filename and lowercase it ** to derive a mutex name. */ zTok = CharLowerW(zName); for (;*zTok;zTok++){ if (*zTok == '\\') *zTok = '_'; } /* Create/open the named mutex */ pFile->hMutex = CreateMutexW(NULL, FALSE, zName); if (!pFile->hMutex){ pFile->lastErrno = GetLastError(); winLogError(SQLITE_ERROR, "winceCreateLock1", zFilename); free(zName); return FALSE; } /* Acquire the mutex before continuing */ winceMutexAcquire(pFile->hMutex); /* Since the names of named mutexes, semaphores, file mappings etc are ** case-sensitive, take advantage of that by uppercasing the mutex name ** and using that as the shared filemapping name. */ CharUpperW(zName); pFile->hShared = CreateFileMappingW(INVALID_HANDLE_VALUE, NULL, PAGE_READWRITE, 0, sizeof(winceLock), zName); /* Set a flag that indicates we're the first to create the memory so it ** must be zero-initialized */ if (GetLastError() == ERROR_ALREADY_EXISTS){ bInit = FALSE; } free(zName); /* If we succeeded in making the shared memory handle, map it. */ if (pFile->hShared){ pFile->shared = (winceLock*)MapViewOfFile(pFile->hShared, FILE_MAP_READ|FILE_MAP_WRITE, 0, 0, sizeof(winceLock)); /* If mapping failed, close the shared memory handle and erase it */ if (!pFile->shared){ pFile->lastErrno = GetLastError(); winLogError(SQLITE_ERROR, "winceCreateLock2", zFilename); CloseHandle(pFile->hShared); pFile->hShared = NULL; } } /* If shared memory could not be created, then close the mutex and fail */ if (pFile->hShared == NULL){ winceMutexRelease(pFile->hMutex); CloseHandle(pFile->hMutex); pFile->hMutex = NULL; return FALSE; } /* Initialize the shared memory if we're supposed to */ if (bInit) { ZeroMemory(pFile->shared, sizeof(winceLock)); } winceMutexRelease(pFile->hMutex); return TRUE; } /* ** Destroy the part of winFile that deals with wince locks */ static void winceDestroyLock(winFile *pFile){ if (pFile->hMutex){ /* Acquire the mutex */ winceMutexAcquire(pFile->hMutex); /* The following blocks should probably assert in debug mode, but they are to cleanup in case any locks remained open */ if (pFile->local.nReaders){ pFile->shared->nReaders --; } if (pFile->local.bReserved){ pFile->shared->bReserved = FALSE; } if (pFile->local.bPending){ pFile->shared->bPending = FALSE; } if (pFile->local.bExclusive){ pFile->shared->bExclusive = FALSE; } /* De-reference and close our copy of the shared memory handle */ UnmapViewOfFile(pFile->shared); CloseHandle(pFile->hShared); /* Done with the mutex */ winceMutexRelease(pFile->hMutex); CloseHandle(pFile->hMutex); pFile->hMutex = NULL; } } /* ** An implementation of the LockFile() API of windows for wince */ static BOOL winceLockFile( HANDLE *phFile, DWORD dwFileOffsetLow, DWORD dwFileOffsetHigh, DWORD nNumberOfBytesToLockLow, DWORD nNumberOfBytesToLockHigh ){ winFile *pFile = HANDLE_TO_WINFILE(phFile); BOOL bReturn = FALSE; UNUSED_PARAMETER(dwFileOffsetHigh); UNUSED_PARAMETER(nNumberOfBytesToLockHigh); if (!pFile->hMutex) return TRUE; winceMutexAcquire(pFile->hMutex); /* Wanting an exclusive lock? */ if (dwFileOffsetLow == (DWORD)SHARED_FIRST && nNumberOfBytesToLockLow == (DWORD)SHARED_SIZE){ if (pFile->shared->nReaders == 0 && pFile->shared->bExclusive == 0){ pFile->shared->bExclusive = TRUE; pFile->local.bExclusive = TRUE; bReturn = TRUE; } } /* Want a read-only lock? */ else if (dwFileOffsetLow == (DWORD)SHARED_FIRST && nNumberOfBytesToLockLow == 1){ if (pFile->shared->bExclusive == 0){ pFile->local.nReaders ++; if (pFile->local.nReaders == 1){ pFile->shared->nReaders ++; } bReturn = TRUE; } } /* Want a pending lock? */ else if (dwFileOffsetLow == (DWORD)PENDING_BYTE && nNumberOfBytesToLockLow == 1){ /* If no pending lock has been acquired, then acquire it */ if (pFile->shared->bPending == 0) { pFile->shared->bPending = TRUE; pFile->local.bPending = TRUE; bReturn = TRUE; } } /* Want a reserved lock? */ else if (dwFileOffsetLow == (DWORD)RESERVED_BYTE && nNumberOfBytesToLockLow == 1){ if (pFile->shared->bReserved == 0) { pFile->shared->bReserved = TRUE; pFile->local.bReserved = TRUE; bReturn = TRUE; } } winceMutexRelease(pFile->hMutex); return bReturn; } /* ** An implementation of the UnlockFile API of windows for wince */ static BOOL winceUnlockFile( HANDLE *phFile, DWORD dwFileOffsetLow, DWORD dwFileOffsetHigh, DWORD nNumberOfBytesToUnlockLow, DWORD nNumberOfBytesToUnlockHigh ){ winFile *pFile = HANDLE_TO_WINFILE(phFile); BOOL bReturn = FALSE; UNUSED_PARAMETER(dwFileOffsetHigh); UNUSED_PARAMETER(nNumberOfBytesToUnlockHigh); if (!pFile->hMutex) return TRUE; winceMutexAcquire(pFile->hMutex); /* Releasing a reader lock or an exclusive lock */ if (dwFileOffsetLow == (DWORD)SHARED_FIRST){ /* Did we have an exclusive lock? */ if (pFile->local.bExclusive){ assert(nNumberOfBytesToUnlockLow == (DWORD)SHARED_SIZE); pFile->local.bExclusive = FALSE; pFile->shared->bExclusive = FALSE; bReturn = TRUE; } /* Did we just have a reader lock? */ else if (pFile->local.nReaders){ assert(nNumberOfBytesToUnlockLow == (DWORD)SHARED_SIZE || nNumberOfBytesToUnlockLow == 1); pFile->local.nReaders --; if (pFile->local.nReaders == 0) { pFile->shared->nReaders --; } bReturn = TRUE; } } /* Releasing a pending lock */ else if (dwFileOffsetLow == (DWORD)PENDING_BYTE && nNumberOfBytesToUnlockLow == 1){ if (pFile->local.bPending){ pFile->local.bPending = FALSE; pFile->shared->bPending = FALSE; bReturn = TRUE; } } /* Releasing a reserved lock */ else if (dwFileOffsetLow == (DWORD)RESERVED_BYTE && nNumberOfBytesToUnlockLow == 1){ if (pFile->local.bReserved) { pFile->local.bReserved = FALSE; pFile->shared->bReserved = FALSE; bReturn = TRUE; } } winceMutexRelease(pFile->hMutex); return bReturn; } /* ** An implementation of the LockFileEx() API of windows for wince */ static BOOL winceLockFileEx( HANDLE *phFile, DWORD dwFlags, DWORD dwReserved, DWORD nNumberOfBytesToLockLow, DWORD nNumberOfBytesToLockHigh, LPOVERLAPPED lpOverlapped ){ UNUSED_PARAMETER(dwReserved); UNUSED_PARAMETER(nNumberOfBytesToLockHigh); /* If the caller wants a shared read lock, forward this call ** to winceLockFile */ if (lpOverlapped->Offset == (DWORD)SHARED_FIRST && dwFlags == 1 && nNumberOfBytesToLockLow == (DWORD)SHARED_SIZE){ return winceLockFile(phFile, SHARED_FIRST, 0, 1, 0); } return FALSE; } /* ** End of the special code for wince *****************************************************************************/ #endif /* SQLITE_OS_WINCE */ /***************************************************************************** ** The next group of routines implement the I/O methods specified ** by the sqlite3_io_methods object. ******************************************************************************/ /* ** Some microsoft compilers lack this definition. */ #ifndef INVALID_SET_FILE_POINTER # define INVALID_SET_FILE_POINTER ((DWORD)-1) #endif /* ** Move the current position of the file handle passed as the first ** argument to offset iOffset within the file. If successful, return 0. ** Otherwise, set pFile->lastErrno and return non-zero. */ static int seekWinFile(winFile *pFile, sqlite3_int64 iOffset){ LONG upperBits; /* Most sig. 32 bits of new offset */ LONG lowerBits; /* Least sig. 32 bits of new offset */ DWORD dwRet; /* Value returned by SetFilePointer() */ upperBits = (LONG)((iOffset>>32) & 0x7fffffff); lowerBits = (LONG)(iOffset & 0xffffffff); /* API oddity: If successful, SetFilePointer() returns a dword ** containing the lower 32-bits of the new file-offset. Or, if it fails, ** it returns INVALID_SET_FILE_POINTER. However according to MSDN, ** INVALID_SET_FILE_POINTER may also be a valid new offset. So to determine ** whether an error has actually occured, it is also necessary to call ** GetLastError(). */ dwRet = SetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN); if( (dwRet==INVALID_SET_FILE_POINTER && GetLastError()!=NO_ERROR) ){ pFile->lastErrno = GetLastError(); winLogError(SQLITE_IOERR_SEEK, "seekWinFile", pFile->zPath); return 1; } return 0; } /* ** Close a file. ** ** It is reported that an attempt to close a handle might sometimes ** fail. This is a very unreasonable result, but windows is notorious ** for being unreasonable so I do not doubt that it might happen. If ** the close fails, we pause for 100 milliseconds and try again. As ** many as MX_CLOSE_ATTEMPT attempts to close the handle are made before ** giving up and returning an error. */ #define MX_CLOSE_ATTEMPT 3 static int winClose(sqlite3_file *id){ int rc, cnt = 0; winFile *pFile = (winFile*)id; assert( id!=0 ); assert( pFile->pShm==0 ); OSTRACE(("CLOSE %d\n", pFile->h)); do{ rc = CloseHandle(pFile->h); /* SimulateIOError( rc=0; cnt=MX_CLOSE_ATTEMPT; ); */ }while( rc==0 && ++cnt < MX_CLOSE_ATTEMPT && (Sleep(100), 1) ); #if SQLITE_OS_WINCE #define WINCE_DELETION_ATTEMPTS 3 winceDestroyLock(pFile); if( pFile->zDeleteOnClose ){ int cnt = 0; while( DeleteFileW(pFile->zDeleteOnClose)==0 && GetFileAttributesW(pFile->zDeleteOnClose)!=0xffffffff && cnt++ < WINCE_DELETION_ATTEMPTS ){ Sleep(100); /* Wait a little before trying again */ } free(pFile->zDeleteOnClose); } #endif OSTRACE(("CLOSE %d %s\n", pFile->h, rc ? "ok" : "failed")); OpenCounter(-1); return rc ? SQLITE_OK : winLogError(SQLITE_IOERR_CLOSE, "winClose", pFile->zPath); } /* ** Read data from a file into a buffer. Return SQLITE_OK if all ** bytes were read successfully and SQLITE_IOERR if anything goes ** wrong. */ static int winRead( sqlite3_file *id, /* File to read from */ void *pBuf, /* Write content into this buffer */ int amt, /* Number of bytes to read */ sqlite3_int64 offset /* Begin reading at this offset */ ){ winFile *pFile = (winFile*)id; /* file handle */ DWORD nRead; /* Number of bytes actually read from file */ int nRetry = 0; /* Number of retrys */ assert( id!=0 ); SimulateIOError(return SQLITE_IOERR_READ); OSTRACE(("READ %d lock=%d\n", pFile->h, pFile->locktype)); if( seekWinFile(pFile, offset) ){ return SQLITE_FULL; } while( !ReadFile(pFile->h, pBuf, amt, &nRead, 0) ){ if( retryIoerr(&nRetry) ) continue; pFile->lastErrno = GetLastError(); return winLogError(SQLITE_IOERR_READ, "winRead", pFile->zPath); } logIoerr(nRetry); if( nRead<(DWORD)amt ){ /* Unread parts of the buffer must be zero-filled */ memset(&((char*)pBuf)[nRead], 0, amt-nRead); return SQLITE_IOERR_SHORT_READ; } return SQLITE_OK; } /* ** Write data from a buffer into a file. Return SQLITE_OK on success ** or some other error code on failure. */ static int winWrite( sqlite3_file *id, /* File to write into */ const void *pBuf, /* The bytes to be written */ int amt, /* Number of bytes to write */ sqlite3_int64 offset /* Offset into the file to begin writing at */ ){ int rc; /* True if error has occured, else false */ winFile *pFile = (winFile*)id; /* File handle */ int nRetry = 0; /* Number of retries */ assert( amt>0 ); assert( pFile ); SimulateIOError(return SQLITE_IOERR_WRITE); SimulateDiskfullError(return SQLITE_FULL); OSTRACE(("WRITE %d lock=%d\n", pFile->h, pFile->locktype)); rc = seekWinFile(pFile, offset); if( rc==0 ){ u8 *aRem = (u8 *)pBuf; /* Data yet to be written */ int nRem = amt; /* Number of bytes yet to be written */ DWORD nWrite; /* Bytes written by each WriteFile() call */ while( nRem>0 ){ if( !WriteFile(pFile->h, aRem, nRem, &nWrite, 0) ){ if( retryIoerr(&nRetry) ) continue; break; } if( nWrite<=0 ) break; aRem += nWrite; nRem -= nWrite; } if( nRem>0 ){ pFile->lastErrno = GetLastError(); rc = 1; } } if( rc ){ if( ( pFile->lastErrno==ERROR_HANDLE_DISK_FULL ) || ( pFile->lastErrno==ERROR_DISK_FULL )){ return SQLITE_FULL; } return winLogError(SQLITE_IOERR_WRITE, "winWrite", pFile->zPath); }else{ logIoerr(nRetry); } return SQLITE_OK; } /* ** Truncate an open file to a specified size */ static int winTruncate(sqlite3_file *id, sqlite3_int64 nByte){ winFile *pFile = (winFile*)id; /* File handle object */ int rc = SQLITE_OK; /* Return code for this function */ assert( pFile ); OSTRACE(("TRUNCATE %d %lld\n", pFile->h, nByte)); SimulateIOError(return SQLITE_IOERR_TRUNCATE); /* If the user has configured a chunk-size for this file, truncate the ** file so that it consists of an integer number of chunks (i.e. the ** actual file size after the operation may be larger than the requested ** size). */ if( pFile->szChunk ){ nByte = ((nByte + pFile->szChunk - 1)/pFile->szChunk) * pFile->szChunk; } /* SetEndOfFile() returns non-zero when successful, or zero when it fails. */ if( seekWinFile(pFile, nByte) ){ rc = winLogError(SQLITE_IOERR_TRUNCATE, "winTruncate1", pFile->zPath); }else if( 0==SetEndOfFile(pFile->h) ){ pFile->lastErrno = GetLastError(); rc = winLogError(SQLITE_IOERR_TRUNCATE, "winTruncate2", pFile->zPath); } OSTRACE(("TRUNCATE %d %lld %s\n", pFile->h, nByte, rc ? "failed" : "ok")); return rc; } #ifdef SQLITE_TEST /* ** Count the number of fullsyncs and normal syncs. This is used to test ** that syncs and fullsyncs are occuring at the right times. */ int sqlite3_sync_count = 0; int sqlite3_fullsync_count = 0; #endif /* ** Make sure all writes to a particular file are committed to disk. */ static int winSync(sqlite3_file *id, int flags){ #if !defined(NDEBUG) || !defined(SQLITE_NO_SYNC) || defined(SQLITE_DEBUG) winFile *pFile = (winFile*)id; BOOL rc; #else UNUSED_PARAMETER(id); #endif assert( pFile ); /* Check that one of SQLITE_SYNC_NORMAL or FULL was passed */ assert((flags&0x0F)==SQLITE_SYNC_NORMAL || (flags&0x0F)==SQLITE_SYNC_FULL ); OSTRACE(("SYNC %d lock=%d\n", pFile->h, pFile->locktype)); /* Unix cannot, but some systems may return SQLITE_FULL from here. This ** line is to test that doing so does not cause any problems. */ SimulateDiskfullError( return SQLITE_FULL ); #ifndef SQLITE_TEST UNUSED_PARAMETER(flags); #else if( (flags&0x0F)==SQLITE_SYNC_FULL ){ sqlite3_fullsync_count++; } sqlite3_sync_count++; #endif /* If we compiled with the SQLITE_NO_SYNC flag, then syncing is a ** no-op */ #ifdef SQLITE_NO_SYNC return SQLITE_OK; #else rc = FlushFileBuffers(pFile->h); SimulateIOError( rc=FALSE ); if( rc ){ return SQLITE_OK; }else{ pFile->lastErrno = GetLastError(); return winLogError(SQLITE_IOERR_FSYNC, "winSync", pFile->zPath); } #endif } /* ** Determine the current size of a file in bytes */ static int winFileSize(sqlite3_file *id, sqlite3_int64 *pSize){ DWORD upperBits; DWORD lowerBits; winFile *pFile = (winFile*)id; DWORD error; assert( id!=0 ); SimulateIOError(return SQLITE_IOERR_FSTAT); lowerBits = GetFileSize(pFile->h, &upperBits); if( (lowerBits == INVALID_FILE_SIZE) && ((error = GetLastError()) != NO_ERROR) ) { pFile->lastErrno = error; return winLogError(SQLITE_IOERR_FSTAT, "winFileSize", pFile->zPath); } *pSize = (((sqlite3_int64)upperBits)<<32) + lowerBits; return SQLITE_OK; } /* ** LOCKFILE_FAIL_IMMEDIATELY is undefined on some Windows systems. */ #ifndef LOCKFILE_FAIL_IMMEDIATELY # define LOCKFILE_FAIL_IMMEDIATELY 1 #endif /* ** Acquire a reader lock. ** Different API routines are called depending on whether or not this ** is Win95 or WinNT. */ static int getReadLock(winFile *pFile){ int res; if( isNT() ){ OVERLAPPED ovlp; ovlp.Offset = SHARED_FIRST; ovlp.OffsetHigh = 0; ovlp.hEvent = 0; res = LockFileEx(pFile->h, LOCKFILE_FAIL_IMMEDIATELY, 0, SHARED_SIZE, 0, &ovlp); /* isNT() is 1 if SQLITE_OS_WINCE==1, so this else is never executed. */ #if SQLITE_OS_WINCE==0 }else{ int lk; sqlite3_randomness(sizeof(lk), &lk); pFile->sharedLockByte = (short)((lk & 0x7fffffff)%(SHARED_SIZE - 1)); res = LockFile(pFile->h, SHARED_FIRST+pFile->sharedLockByte, 0, 1, 0); #endif } if( res == 0 ){ pFile->lastErrno = GetLastError(); /* No need to log a failure to lock */ } return res; } /* ** Undo a readlock */ static int unlockReadLock(winFile *pFile){ int res; if( isNT() ){ res = UnlockFile(pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0); /* isNT() is 1 if SQLITE_OS_WINCE==1, so this else is never executed. */ #if SQLITE_OS_WINCE==0 }else{ res = UnlockFile(pFile->h, SHARED_FIRST + pFile->sharedLockByte, 0, 1, 0); #endif } if( res==0 && GetLastError()!=ERROR_NOT_LOCKED ){ pFile->lastErrno = GetLastError(); winLogError(SQLITE_IOERR_UNLOCK, "unlockReadLock", pFile->zPath); } return res; } /* ** Lock the file with the lock specified by parameter locktype - one ** of the following: ** ** (1) SHARED_LOCK ** (2) RESERVED_LOCK ** (3) PENDING_LOCK ** (4) EXCLUSIVE_LOCK ** ** Sometimes when requesting one lock state, additional lock states ** are inserted in between. The locking might fail on one of the later ** transitions leaving the lock state different from what it started but ** still short of its goal. The following chart shows the allowed ** transitions and the inserted intermediate states: ** ** UNLOCKED -> SHARED ** SHARED -> RESERVED ** SHARED -> (PENDING) -> EXCLUSIVE ** RESERVED -> (PENDING) -> EXCLUSIVE ** PENDING -> EXCLUSIVE ** ** This routine will only increase a lock. The winUnlock() routine ** erases all locks at once and returns us immediately to locking level 0. ** It is not possible to lower the locking level one step at a time. You ** must go straight to locking level 0. */ static int winLock(sqlite3_file *id, int locktype){ int rc = SQLITE_OK; /* Return code from subroutines */ int res = 1; /* Result of a windows lock call */ int newLocktype; /* Set pFile->locktype to this value before exiting */ int gotPendingLock = 0;/* True if we acquired a PENDING lock this time */ winFile *pFile = (winFile*)id; DWORD error = NO_ERROR; assert( id!=0 ); OSTRACE(("LOCK %d %d was %d(%d)\n", pFile->h, locktype, pFile->locktype, pFile->sharedLockByte)); /* 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 ){ return SQLITE_OK; } /* Make sure the locking sequence is correct */ assert( pFile->locktype!=NO_LOCK || locktype==SHARED_LOCK ); assert( locktype!=PENDING_LOCK ); assert( locktype!=RESERVED_LOCK || pFile->locktype==SHARED_LOCK ); /* Lock the PENDING_LOCK byte if we need to acquire a PENDING lock or ** a SHARED lock. If we are acquiring a SHARED lock, the acquisition of ** the PENDING_LOCK byte is temporary. */ newLocktype = pFile->locktype; if( (pFile->locktype==NO_LOCK) || ( (locktype==EXCLUSIVE_LOCK) && (pFile->locktype==RESERVED_LOCK)) ){ int cnt = 3; while( cnt-->0 && (res = LockFile(pFile->h, PENDING_BYTE, 0, 1, 0))==0 ){ /* Try 3 times to get the pending lock. The pending lock might be ** held by another reader process who will release it momentarily. */ OSTRACE(("could not get a PENDING lock. cnt=%d\n", cnt)); Sleep(1); } gotPendingLock = res; if( !res ){ error = GetLastError(); } } /* Acquire a shared lock */ if( locktype==SHARED_LOCK && res ){ assert( pFile->locktype==NO_LOCK ); res = getReadLock(pFile); if( res ){ newLocktype = SHARED_LOCK; }else{ error = GetLastError(); } } /* Acquire a RESERVED lock */ if( locktype==RESERVED_LOCK && res ){ assert( pFile->locktype==SHARED_LOCK ); res = LockFile(pFile->h, RESERVED_BYTE, 0, 1, 0); if( res ){ newLocktype = RESERVED_LOCK; }else{ error = GetLastError(); } } /* Acquire a PENDING lock */ if( locktype==EXCLUSIVE_LOCK && res ){ newLocktype = PENDING_LOCK; gotPendingLock = 0; } /* Acquire an EXCLUSIVE lock */ if( locktype==EXCLUSIVE_LOCK && res ){ assert( pFile->locktype>=SHARED_LOCK ); res = unlockReadLock(pFile); OSTRACE(("unreadlock = %d\n", res)); res = LockFile(pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0); if( res ){ newLocktype = EXCLUSIVE_LOCK; }else{ error = GetLastError(); OSTRACE(("error-code = %d\n", error)); getReadLock(pFile); } } /* If we are holding a PENDING lock that ought to be released, then ** release it now. */ if( gotPendingLock && locktype==SHARED_LOCK ){ UnlockFile(pFile->h, PENDING_BYTE, 0, 1, 0); } /* Update the state of the lock has held in the file descriptor then ** return the appropriate result code. */ if( res ){ rc = SQLITE_OK; }else{ OSTRACE(("LOCK FAILED %d trying for %d but got %d\n", pFile->h, locktype, newLocktype)); pFile->lastErrno = error; rc = SQLITE_BUSY; } pFile->locktype = (u8)newLocktype; return rc; } /* ** This routine checks if there is a RESERVED lock held on the specified ** file by this or any other process. If such a lock is held, return ** non-zero, otherwise zero. */ static int winCheckReservedLock(sqlite3_file *id, int *pResOut){ int rc; winFile *pFile = (winFile*)id; SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; ); assert( id!=0 ); if( pFile->locktype>=RESERVED_LOCK ){ rc = 1; OSTRACE(("TEST WR-LOCK %d %d (local)\n", pFile->h, rc)); }else{ rc = LockFile(pFile->h, RESERVED_BYTE, 0, 1, 0); if( rc ){ UnlockFile(pFile->h, RESERVED_BYTE, 0, 1, 0); } rc = !rc; OSTRACE(("TEST WR-LOCK %d %d (remote)\n", pFile->h, rc)); } *pResOut = rc; return SQLITE_OK; } /* ** Lower the locking level on file descriptor id to locktype. locktype ** must be either NO_LOCK or SHARED_LOCK. ** ** If the locking level of the file descriptor is already at or below ** the requested locking level, this routine is a no-op. ** ** It is not possible for this routine to fail if the second argument ** is NO_LOCK. If the second argument is SHARED_LOCK then this routine ** might return SQLITE_IOERR; */ static int winUnlock(sqlite3_file *id, int locktype){ int type; winFile *pFile = (winFile*)id; int rc = SQLITE_OK; assert( pFile!=0 ); assert( locktype<=SHARED_LOCK ); OSTRACE(("UNLOCK %d to %d was %d(%d)\n", pFile->h, locktype, pFile->locktype, pFile->sharedLockByte)); type = pFile->locktype; if( type>=EXCLUSIVE_LOCK ){ UnlockFile(pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0); if( locktype==SHARED_LOCK && !getReadLock(pFile) ){ /* This should never happen. We should always be able to ** reacquire the read lock */ rc = winLogError(SQLITE_IOERR_UNLOCK, "winUnlock", pFile->zPath); } } if( type>=RESERVED_LOCK ){ UnlockFile(pFile->h, RESERVED_BYTE, 0, 1, 0); } if( locktype==NO_LOCK && type>=SHARED_LOCK ){ unlockReadLock(pFile); } if( type>=PENDING_LOCK ){ UnlockFile(pFile->h, PENDING_BYTE, 0, 1, 0); } pFile->locktype = (u8)locktype; return rc; } /* ** Control and query of the open file handle. */ static int winFileControl(sqlite3_file *id, int op, void *pArg){ winFile *pFile = (winFile*)id; switch( op ){ case SQLITE_FCNTL_LOCKSTATE: { *(int*)pArg = pFile->locktype; return SQLITE_OK; } case SQLITE_LAST_ERRNO: { *(int*)pArg = (int)pFile->lastErrno; return SQLITE_OK; } case SQLITE_FCNTL_CHUNK_SIZE: { pFile->szChunk = *(int *)pArg; return SQLITE_OK; } case SQLITE_FCNTL_SIZE_HINT: { sqlite3_int64 sz = *(sqlite3_int64*)pArg; SimulateIOErrorBenign(1); winTruncate(id, sz); SimulateIOErrorBenign(0); return SQLITE_OK; } case SQLITE_FCNTL_PERSIST_WAL: { int bPersist = *(int*)pArg; if( bPersist<0 ){ *(int*)pArg = pFile->bPersistWal; }else{ pFile->bPersistWal = bPersist!=0; } return SQLITE_OK; } case SQLITE_FCNTL_SYNC_OMITTED: { return SQLITE_OK; } case SQLITE_FCNTL_WIN32_AV_RETRY: { int *a = (int*)pArg; if( a[0]>0 ){ win32IoerrRetry = a[0]; }else{ a[0] = win32IoerrRetry; } if( a[1]>0 ){ win32IoerrRetryDelay = a[1]; }else{ a[1] = win32IoerrRetryDelay; } return SQLITE_OK; } } return SQLITE_NOTFOUND; } /* ** Return the sector size in bytes of the underlying block device for ** the specified file. This is almost always 512 bytes, but may be ** larger for some devices. ** ** SQLite code assumes this function cannot fail. It also assumes that ** if two files are created in the same file-system directory (i.e. ** a database and its journal file) that the sector size will be the ** same for both. */ static int winSectorSize(sqlite3_file *id){ assert( id!=0 ); return (int)(((winFile*)id)->sectorSize); } /* ** Return a vector of device characteristics. */ static int winDeviceCharacteristics(sqlite3_file *id){ UNUSED_PARAMETER(id); return SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN; } #ifndef SQLITE_OMIT_WAL /* ** Windows will only let you create file view mappings ** on allocation size granularity boundaries. ** During sqlite3_os_init() we do a GetSystemInfo() ** to get the granularity size. */ SYSTEM_INFO winSysInfo; /* ** Helper functions to obtain and relinquish the global mutex. The ** global mutex is used to protect the winLockInfo objects used by ** this file, all of which may be shared by multiple threads. ** ** Function winShmMutexHeld() is used to assert() that the global mutex ** is held when required. This function is only used as part of assert() ** statements. e.g. ** ** winShmEnterMutex() ** assert( winShmMutexHeld() ); ** winShmLeaveMutex() */ static void winShmEnterMutex(void){ sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER)); } static void winShmLeaveMutex(void){ sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER)); } #ifdef SQLITE_DEBUG static int winShmMutexHeld(void) { return sqlite3_mutex_held(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER)); } #endif /* ** Object used to represent a single file opened and mmapped to provide ** shared memory. When multiple threads all reference the same ** log-summary, each thread has its own winFile object, but they all ** point to a single instance of this object. In other words, each ** log-summary is opened only once per process. ** ** winShmMutexHeld() must be true when creating or destroying ** this object or while reading or writing the following fields: ** ** nRef ** pNext ** ** The following fields are read-only after the object is created: ** ** fid ** zFilename ** ** Either winShmNode.mutex must be held or winShmNode.nRef==0 and ** winShmMutexHeld() is true when reading or writing any other field ** in this structure. ** */ struct winShmNode { sqlite3_mutex *mutex; /* Mutex to access this object */ char *zFilename; /* Name of the file */ winFile hFile; /* File handle from winOpen */ 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 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 */ #endif }; /* ** A global array of all winShmNode objects. ** ** The winShmMutexHeld() must be true while reading or writing this list. */ static winShmNode *winShmNodeList = 0; /* ** Structure used internally by this VFS to record the state of an ** open shared memory connection. ** ** The following fields are initialized when this object is created and ** are read-only thereafter: ** ** winShm.pShmNode ** winShm.id ** ** All other fields are read/write. The winShm.pShmNode->mutex must be held ** while accessing any read/write fields. */ struct winShm { winShmNode *pShmNode; /* The underlying winShmNode object */ winShm *pNext; /* Next winShm with the same winShmNode */ u8 hasMutex; /* True if holding the winShmNode mutex */ u16 sharedMask; /* Mask of shared locks held */ u16 exclMask; /* Mask of exclusive locks held */ #ifdef SQLITE_DEBUG u8 id; /* Id of this connection with its winShmNode */ #endif }; /* ** Constants used for locking */ #define WIN_SHM_BASE ((22+SQLITE_SHM_NLOCK)*4) /* first lock byte */ #define WIN_SHM_DMS (WIN_SHM_BASE+SQLITE_SHM_NLOCK) /* deadman switch */ /* ** Apply advisory locks for all n bytes beginning at ofst. */ #define _SHM_UNLCK 1 #define _SHM_RDLCK 2 #define _SHM_WRLCK 3 static int winShmSystemLock( winShmNode *pFile, /* Apply locks to this open shared-memory segment */ int lockType, /* _SHM_UNLCK, _SHM_RDLCK, or _SHM_WRLCK */ int ofst, /* Offset to first byte to be locked/unlocked */ int nByte /* Number of bytes to lock or unlock */ ){ OVERLAPPED ovlp; DWORD dwFlags; int rc = 0; /* Result code form Lock/UnlockFileEx() */ /* Access to the winShmNode object is serialized by the caller */ assert( sqlite3_mutex_held(pFile->mutex) || pFile->nRef==0 ); /* Initialize the locking parameters */ dwFlags = LOCKFILE_FAIL_IMMEDIATELY; if( lockType == _SHM_WRLCK ) dwFlags |= LOCKFILE_EXCLUSIVE_LOCK; memset(&ovlp, 0, sizeof(OVERLAPPED)); ovlp.Offset = ofst; /* Release/Acquire the system-level lock */ if( lockType==_SHM_UNLCK ){ rc = UnlockFileEx(pFile->hFile.h, 0, nByte, 0, &ovlp); }else{ rc = LockFileEx(pFile->hFile.h, dwFlags, 0, nByte, 0, &ovlp); } if( rc!= 0 ){ rc = SQLITE_OK; }else{ pFile->lastErrno = GetLastError(); rc = SQLITE_BUSY; } OSTRACE(("SHM-LOCK %d %s %s 0x%08lx\n", pFile->hFile.h, rc==SQLITE_OK ? "ok" : "failed", lockType==_SHM_UNLCK ? "UnlockFileEx" : "LockFileEx", pFile->lastErrno)); return rc; } /* Forward references to VFS methods */ static int winOpen(sqlite3_vfs*,const char*,sqlite3_file*,int,int*); static int winDelete(sqlite3_vfs *,const char*,int); /* ** Purge the winShmNodeList list of all entries with winShmNode.nRef==0. ** ** This is not a VFS shared-memory method; it is a utility function called ** by VFS shared-memory methods. */ static void winShmPurge(sqlite3_vfs *pVfs, int deleteFlag){ winShmNode **pp; winShmNode *p; BOOL bRc; assert( winShmMutexHeld() ); pp = &winShmNodeList; while( (p = *pp)!=0 ){ if( p->nRef==0 ){ int i; if( p->mutex ) sqlite3_mutex_free(p->mutex); for(i=0; inRegion; i++){ bRc = UnmapViewOfFile(p->aRegion[i].pMap); OSTRACE(("SHM-PURGE pid-%d unmap region=%d %s\n", (int)GetCurrentProcessId(), i, bRc ? "ok" : "failed")); bRc = CloseHandle(p->aRegion[i].hMap); OSTRACE(("SHM-PURGE pid-%d close region=%d %s\n", (int)GetCurrentProcessId(), i, bRc ? "ok" : "failed")); } if( p->hFile.h != INVALID_HANDLE_VALUE ){ SimulateIOErrorBenign(1); winClose((sqlite3_file *)&p->hFile); SimulateIOErrorBenign(0); } if( deleteFlag ){ SimulateIOErrorBenign(1); winDelete(pVfs, p->zFilename, 0); SimulateIOErrorBenign(0); } *pp = p->pNext; sqlite3_free(p->aRegion); sqlite3_free(p); }else{ pp = &p->pNext; } } } /* ** Open the shared-memory area associated with database file pDbFd. ** ** When opening a new shared-memory file, if no other instances of that ** file are currently open, in this process or in other processes, then ** the file must be truncated to zero length or have its header cleared. */ static int winOpenSharedMemory(winFile *pDbFd){ struct winShm *p; /* The connection to be opened */ struct winShmNode *pShmNode = 0; /* The underlying mmapped file */ int rc; /* Result code */ struct winShmNode *pNew; /* Newly allocated winShmNode */ int nName; /* Size of zName in bytes */ assert( pDbFd->pShm==0 ); /* Not previously opened */ /* Allocate space for the new sqlite3_shm object. Also speculatively ** allocate space for a new winShmNode and filename. */ p = sqlite3_malloc( sizeof(*p) ); if( p==0 ) return SQLITE_NOMEM; memset(p, 0, sizeof(*p)); nName = sqlite3Strlen30(pDbFd->zPath); pNew = sqlite3_malloc( sizeof(*pShmNode) + nName + 15 ); if( pNew==0 ){ sqlite3_free(p); return SQLITE_NOMEM; } memset(pNew, 0, sizeof(*pNew)); pNew->zFilename = (char*)&pNew[1]; sqlite3_snprintf(nName+15, pNew->zFilename, "%s-shm", pDbFd->zPath); sqlite3FileSuffix3(pDbFd->zPath, pNew->zFilename); /* Look to see if there is an existing winShmNode that can be used. ** If no matching winShmNode currently exists, create a new one. */ winShmEnterMutex(); for(pShmNode = winShmNodeList; pShmNode; pShmNode=pShmNode->pNext){ /* TBD need to come up with better match here. Perhaps ** use FILE_ID_BOTH_DIR_INFO Structure. */ if( sqlite3StrICmp(pShmNode->zFilename, pNew->zFilename)==0 ) break; } if( pShmNode ){ sqlite3_free(pNew); }else{ pShmNode = pNew; pNew = 0; ((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; } rc = winOpen(pDbFd->pVfs, pShmNode->zFilename, /* Name of the file (UTF-8) */ (sqlite3_file*)&pShmNode->hFile, /* File handle here */ SQLITE_OPEN_WAL | SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE, /* Mode flags */ 0); if( SQLITE_OK!=rc ){ rc = SQLITE_CANTOPEN_BKPT; goto shm_open_err; } /* Check to see if another process is holding the dead-man switch. ** If not, truncate the file to zero length. */ if( winShmSystemLock(pShmNode, _SHM_WRLCK, WIN_SHM_DMS, 1)==SQLITE_OK ){ rc = winTruncate((sqlite3_file *)&pShmNode->hFile, 0); if( rc!=SQLITE_OK ){ rc = winLogError(SQLITE_IOERR_SHMOPEN, "winOpenShm", pDbFd->zPath); } } if( rc==SQLITE_OK ){ winShmSystemLock(pShmNode, _SHM_UNLCK, WIN_SHM_DMS, 1); rc = winShmSystemLock(pShmNode, _SHM_RDLCK, WIN_SHM_DMS, 1); } if( rc ) goto shm_open_err; } /* Make the new connection a child of the winShmNode */ p->pShmNode = pShmNode; #ifdef SQLITE_DEBUG p->id = pShmNode->nextShmId++; #endif pShmNode->nRef++; pDbFd->pShm = p; winShmLeaveMutex(); /* The reference count on pShmNode has already been incremented under ** the cover of the winShmEnterMutex() mutex and the pointer from the ** new (struct winShm) object to the pShmNode has been set. All that is ** left to do is to link the new object into the linked list starting ** at pShmNode->pFirst. This must be done while holding the pShmNode->mutex ** mutex. */ sqlite3_mutex_enter(pShmNode->mutex); p->pNext = pShmNode->pFirst; pShmNode->pFirst = p; sqlite3_mutex_leave(pShmNode->mutex); return SQLITE_OK; /* Jump here on any error */ shm_open_err: winShmSystemLock(pShmNode, _SHM_UNLCK, WIN_SHM_DMS, 1); winShmPurge(pDbFd->pVfs, 0); /* This call frees pShmNode if required */ sqlite3_free(p); sqlite3_free(pNew); winShmLeaveMutex(); return rc; } /* ** Close a connection to shared-memory. Delete the underlying ** storage if deleteFlag is true. */ static int winShmUnmap( sqlite3_file *fd, /* Database holding shared memory */ int deleteFlag /* Delete after closing if true */ ){ winFile *pDbFd; /* Database holding shared-memory */ winShm *p; /* The connection to be closed */ winShmNode *pShmNode; /* The underlying shared-memory file */ winShm **pp; /* For looping over sibling connections */ pDbFd = (winFile*)fd; p = pDbFd->pShm; if( p==0 ) return SQLITE_OK; pShmNode = p->pShmNode; /* Remove connection p from the set of connections associated ** with pShmNode */ sqlite3_mutex_enter(pShmNode->mutex); for(pp=&pShmNode->pFirst; (*pp)!=p; pp = &(*pp)->pNext){} *pp = p->pNext; /* Free the connection p */ sqlite3_free(p); pDbFd->pShm = 0; sqlite3_mutex_leave(pShmNode->mutex); /* If pShmNode->nRef has reached 0, then close the underlying ** shared-memory file, too */ winShmEnterMutex(); assert( pShmNode->nRef>0 ); pShmNode->nRef--; if( pShmNode->nRef==0 ){ winShmPurge(pDbFd->pVfs, deleteFlag); } winShmLeaveMutex(); return SQLITE_OK; } /* ** Change the lock state for a shared-memory segment. */ static int winShmLock( sqlite3_file *fd, /* Database file holding the shared memory */ int ofst, /* First lock to acquire or release */ int n, /* Number of locks to acquire or release */ int flags /* What to do with the lock */ ){ winFile *pDbFd = (winFile*)fd; /* Connection holding shared memory */ winShm *p = pDbFd->pShm; /* The shared memory being locked */ winShm *pX; /* For looping over all siblings */ winShmNode *pShmNode = p->pShmNode; int rc = SQLITE_OK; /* Result code */ u16 mask; /* Mask of locks to take or release */ assert( ofst>=0 && ofst+n<=SQLITE_SHM_NLOCK ); assert( n>=1 ); assert( flags==(SQLITE_SHM_LOCK | SQLITE_SHM_SHARED) || flags==(SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE) || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED) || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE) ); assert( n==1 || (flags & SQLITE_SHM_EXCLUSIVE)!=0 ); mask = (u16)((1U<<(ofst+n)) - (1U<1 || mask==(1<mutex); if( flags & SQLITE_SHM_UNLOCK ){ u16 allMask = 0; /* Mask of locks held by siblings */ /* See if any siblings hold this same lock */ for(pX=pShmNode->pFirst; pX; pX=pX->pNext){ if( pX==p ) continue; assert( (pX->exclMask & (p->exclMask|p->sharedMask))==0 ); allMask |= pX->sharedMask; } /* Unlock the system-level locks */ if( (mask & allMask)==0 ){ rc = winShmSystemLock(pShmNode, _SHM_UNLCK, ofst+WIN_SHM_BASE, n); }else{ rc = SQLITE_OK; } /* Undo the local locks */ if( rc==SQLITE_OK ){ p->exclMask &= ~mask; p->sharedMask &= ~mask; } }else if( flags & SQLITE_SHM_SHARED ){ u16 allShared = 0; /* Union of locks held by connections other than "p" */ /* Find out which shared locks are already held by sibling connections. ** If any sibling already holds an exclusive lock, go ahead and return ** SQLITE_BUSY. */ for(pX=pShmNode->pFirst; pX; pX=pX->pNext){ if( (pX->exclMask & mask)!=0 ){ rc = SQLITE_BUSY; break; } allShared |= pX->sharedMask; } /* Get shared locks at the system level, if necessary */ if( rc==SQLITE_OK ){ if( (allShared & mask)==0 ){ rc = winShmSystemLock(pShmNode, _SHM_RDLCK, ofst+WIN_SHM_BASE, n); }else{ rc = SQLITE_OK; } } /* Get the local shared locks */ if( rc==SQLITE_OK ){ p->sharedMask |= mask; } }else{ /* Make sure no sibling connections hold locks that will block this ** lock. If any do, return SQLITE_BUSY right away. */ for(pX=pShmNode->pFirst; pX; pX=pX->pNext){ if( (pX->exclMask & mask)!=0 || (pX->sharedMask & mask)!=0 ){ rc = SQLITE_BUSY; break; } } /* Get the exclusive locks at the system level. Then if successful ** also mark the local connection as being locked. */ if( rc==SQLITE_OK ){ rc = winShmSystemLock(pShmNode, _SHM_WRLCK, ofst+WIN_SHM_BASE, n); if( rc==SQLITE_OK ){ assert( (p->sharedMask & mask)==0 ); p->exclMask |= mask; } } } sqlite3_mutex_leave(pShmNode->mutex); OSTRACE(("SHM-LOCK shmid-%d, pid-%d got %03x,%03x %s\n", p->id, (int)GetCurrentProcessId(), p->sharedMask, p->exclMask, rc ? "failed" : "ok")); return rc; } /* ** Implement a memory barrier or memory fence on shared memory. ** ** All loads and stores begun before the barrier must complete before ** any load or store begun after the barrier. */ static void winShmBarrier( sqlite3_file *fd /* Database holding the shared memory */ ){ UNUSED_PARAMETER(fd); /* MemoryBarrier(); // does not work -- do not know why not */ winShmEnterMutex(); winShmLeaveMutex(); } /* ** 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. ** ** 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. ** ** 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; int rc = SQLITE_OK; if( !p ){ rc = winOpenSharedMemory(pDbFd); if( rc!=SQLITE_OK ) return rc; p = pDbFd->pShm; } pShmNode = p->pShmNode; sqlite3_mutex_enter(pShmNode->mutex); 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 ){ rc = winLogError(SQLITE_IOERR_SHMSIZE, "winShmMap1", pDbFd->zPath); goto shmpage_out; } if( szhFile, nByte); if( rc!=SQLITE_OK ){ rc = winLogError(SQLITE_IOERR_SHMSIZE, "winShmMap2", pDbFd->zPath); 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 ); OSTRACE(("SHM-MAP pid-%d create region=%d nbyte=%d %s\n", (int)GetCurrentProcessId(), pShmNode->nRegion, nByte, hMap ? "ok" : "failed")); if( hMap ){ int iOffset = pShmNode->nRegion*szRegion; int iOffsetShift = iOffset % winSysInfo.dwAllocationGranularity; pMap = MapViewOfFile(hMap, FILE_MAP_WRITE | FILE_MAP_READ, 0, iOffset - iOffsetShift, szRegion + iOffsetShift ); OSTRACE(("SHM-MAP pid-%d map region=%d offset=%d size=%d %s\n", (int)GetCurrentProcessId(), pShmNode->nRegion, iOffset, szRegion, pMap ? "ok" : "failed")); } if( !pMap ){ pShmNode->lastErrno = GetLastError(); rc = winLogError(SQLITE_IOERR_SHMMAP, "winShmMap3", pDbFd->zPath); if( hMap ) CloseHandle(hMap); goto shmpage_out; } pShmNode->aRegion[pShmNode->nRegion].pMap = pMap; pShmNode->aRegion[pShmNode->nRegion].hMap = hMap; pShmNode->nRegion++; } } shmpage_out: if( pShmNode->nRegion>iRegion ){ int iOffset = iRegion*szRegion; int iOffsetShift = iOffset % winSysInfo.dwAllocationGranularity; char *p = (char *)pShmNode->aRegion[iRegion].pMap; *pp = (void *)&p[iOffsetShift]; }else{ *pp = 0; } sqlite3_mutex_leave(pShmNode->mutex); return rc; } #else # define winShmMap 0 # define winShmLock 0 # define winShmBarrier 0 # define winShmUnmap 0 #endif /* #ifndef SQLITE_OMIT_WAL */ /* ** Here ends the implementation of all sqlite3_file methods. ** ********************** End sqlite3_file Methods ******************************* ******************************************************************************/ /* ** This vector defines all the methods that can operate on an ** sqlite3_file for win32. */ static const sqlite3_io_methods winIoMethod = { 2, /* iVersion */ winClose, /* xClose */ winRead, /* xRead */ winWrite, /* xWrite */ winTruncate, /* xTruncate */ winSync, /* xSync */ winFileSize, /* xFileSize */ winLock, /* xLock */ winUnlock, /* xUnlock */ winCheckReservedLock, /* xCheckReservedLock */ winFileControl, /* xFileControl */ winSectorSize, /* xSectorSize */ winDeviceCharacteristics, /* xDeviceCharacteristics */ winShmMap, /* xShmMap */ winShmLock, /* xShmLock */ winShmBarrier, /* xShmBarrier */ winShmUnmap /* xShmUnmap */ }; /**************************************************************************** **************************** sqlite3_vfs methods **************************** ** ** This division contains the implementation of methods on the ** sqlite3_vfs object. */ /* ** Convert a UTF-8 filename into whatever form the underlying ** operating system wants filenames in. Space to hold the result ** is obtained from malloc and must be freed by the calling ** function. */ static void *convertUtf8Filename(const char *zFilename){ void *zConverted = 0; if( isNT() ){ zConverted = utf8ToUnicode(zFilename); /* isNT() is 1 if SQLITE_OS_WINCE==1, so this else is never executed. */ #if SQLITE_OS_WINCE==0 }else{ zConverted = sqlite3_win32_utf8_to_mbcs(zFilename); #endif } /* caller will handle out of memory */ return zConverted; } /* ** Create a temporary file name in zBuf. zBuf must be big enough to ** hold at pVfs->mxPathname characters. */ static int getTempname(int nBuf, char *zBuf){ static char zChars[] = "abcdefghijklmnopqrstuvwxyz" "ABCDEFGHIJKLMNOPQRSTUVWXYZ" "0123456789"; size_t i, j; char zTempPath[MAX_PATH+1]; /* 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 ); if( sqlite3_temp_directory ){ sqlite3_snprintf(MAX_PATH-30, zTempPath, "%s", sqlite3_temp_directory); }else if( isNT() ){ char *zMulti; WCHAR zWidePath[MAX_PATH]; GetTempPathW(MAX_PATH-30, zWidePath); zMulti = unicodeToUtf8(zWidePath); if( zMulti ){ sqlite3_snprintf(MAX_PATH-30, zTempPath, "%s", zMulti); free(zMulti); }else{ return SQLITE_NOMEM; } /* isNT() is 1 if SQLITE_OS_WINCE==1, so this else is never executed. ** Since the ASCII version of these Windows API do not exist for WINCE, ** it's important to not reference them for WINCE builds. */ #if SQLITE_OS_WINCE==0 }else{ char *zUtf8; char zMbcsPath[MAX_PATH]; GetTempPathA(MAX_PATH-30, zMbcsPath); zUtf8 = sqlite3_win32_mbcs_to_utf8(zMbcsPath); if( zUtf8 ){ sqlite3_snprintf(MAX_PATH-30, zTempPath, "%s", zUtf8); free(zUtf8); }else{ return SQLITE_NOMEM; } #endif } /* Check that the output buffer is large enough for the temporary file ** name. If it is not, return SQLITE_ERROR. */ if( (sqlite3Strlen30(zTempPath) + sqlite3Strlen30(SQLITE_TEMP_FILE_PREFIX) + 17) >= nBuf ){ return SQLITE_ERROR; } for(i=sqlite3Strlen30(zTempPath); i>0 && zTempPath[i-1]=='\\'; i--){} zTempPath[i] = 0; sqlite3_snprintf(nBuf-17, zBuf, "%s\\"SQLITE_TEMP_FILE_PREFIX, zTempPath); j = sqlite3Strlen30(zBuf); sqlite3_randomness(15, &zBuf[j]); for(i=0; i<15; i++, j++){ zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ]; } zBuf[j] = 0; OSTRACE(("TEMP FILENAME: %s\n", zBuf)); return SQLITE_OK; } /* ** Open a file. */ static int winOpen( sqlite3_vfs *pVfs, /* Not used */ const char *zName, /* Name of the file (UTF-8) */ sqlite3_file *id, /* Write the SQLite file handle here */ int flags, /* Open mode flags */ int *pOutFlags /* Status return flags */ ){ HANDLE h; DWORD dwDesiredAccess; DWORD dwShareMode; DWORD dwCreationDisposition; DWORD dwFlagsAndAttributes = 0; #if SQLITE_OS_WINCE int isTemp = 0; #endif winFile *pFile = (winFile*)id; void *zConverted; /* Filename in OS encoding */ const char *zUtf8Name = zName; /* Filename in UTF-8 encoding */ int cnt = 0; /* If argument zPath is a NULL pointer, this function is required to open ** a temporary file. Use this buffer to store the file name in. */ char zTmpname[MAX_PATH+1]; /* Buffer used to create temp filename */ int rc = SQLITE_OK; /* Function Return Code */ #if !defined(NDEBUG) || SQLITE_OS_WINCE int eType = flags&0xFFFFFF00; /* Type of file to open */ #endif int isExclusive = (flags & SQLITE_OPEN_EXCLUSIVE); int isDelete = (flags & SQLITE_OPEN_DELETEONCLOSE); int isCreate = (flags & SQLITE_OPEN_CREATE); #ifndef NDEBUG int isReadonly = (flags & SQLITE_OPEN_READONLY); #endif int isReadWrite = (flags & SQLITE_OPEN_READWRITE); #ifndef NDEBUG int isOpenJournal = (isCreate && ( eType==SQLITE_OPEN_MASTER_JOURNAL || eType==SQLITE_OPEN_MAIN_JOURNAL || eType==SQLITE_OPEN_WAL )); #endif /* Check the following statements are true: ** ** (a) Exactly one of the READWRITE and READONLY flags must be set, and ** (b) if CREATE is set, then READWRITE must also be set, and ** (c) if EXCLUSIVE is set, then CREATE must also be set. ** (d) if DELETEONCLOSE is set, then CREATE must also be set. */ assert((isReadonly==0 || isReadWrite==0) && (isReadWrite || isReadonly)); assert(isCreate==0 || isReadWrite); assert(isExclusive==0 || isCreate); assert(isDelete==0 || isCreate); /* The main DB, main journal, WAL file and master journal are never ** automatically deleted. Nor are they ever temporary files. */ assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_DB ); assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_JOURNAL ); assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MASTER_JOURNAL ); assert( (!isDelete && zName) || eType!=SQLITE_OPEN_WAL ); /* Assert that the upper layer has set one of the "file-type" flags. */ assert( eType==SQLITE_OPEN_MAIN_DB || eType==SQLITE_OPEN_TEMP_DB || eType==SQLITE_OPEN_MAIN_JOURNAL || eType==SQLITE_OPEN_TEMP_JOURNAL || eType==SQLITE_OPEN_SUBJOURNAL || eType==SQLITE_OPEN_MASTER_JOURNAL || eType==SQLITE_OPEN_TRANSIENT_DB || eType==SQLITE_OPEN_WAL ); assert( id!=0 ); UNUSED_PARAMETER(pVfs); pFile->h = INVALID_HANDLE_VALUE; /* If the second argument to this function is NULL, generate a ** temporary file name to use */ if( !zUtf8Name ){ assert(isDelete && !isOpenJournal); rc = getTempname(MAX_PATH+1, zTmpname); if( rc!=SQLITE_OK ){ return rc; } zUtf8Name = zTmpname; } /* Convert the filename to the system encoding. */ zConverted = convertUtf8Filename(zUtf8Name); if( zConverted==0 ){ return SQLITE_NOMEM; } if( isReadWrite ){ dwDesiredAccess = GENERIC_READ | GENERIC_WRITE; }else{ dwDesiredAccess = GENERIC_READ; } /* SQLITE_OPEN_EXCLUSIVE is used to make sure that a new file is ** created. SQLite doesn't use it to indicate "exclusive access" ** as it is usually understood. */ if( isExclusive ){ /* Creates a new file, only if it does not already exist. */ /* If the file exists, it fails. */ dwCreationDisposition = CREATE_NEW; }else if( isCreate ){ /* Open existing file, or create if it doesn't exist */ dwCreationDisposition = OPEN_ALWAYS; }else{ /* Opens a file, only if it exists. */ dwCreationDisposition = OPEN_EXISTING; } dwShareMode = FILE_SHARE_READ | FILE_SHARE_WRITE; if( isDelete ){ #if SQLITE_OS_WINCE dwFlagsAndAttributes = FILE_ATTRIBUTE_HIDDEN; isTemp = 1; #else dwFlagsAndAttributes = FILE_ATTRIBUTE_TEMPORARY | FILE_ATTRIBUTE_HIDDEN | FILE_FLAG_DELETE_ON_CLOSE; #endif }else{ dwFlagsAndAttributes = FILE_ATTRIBUTE_NORMAL; } /* Reports from the internet are that performance is always ** better if FILE_FLAG_RANDOM_ACCESS is used. Ticket #2699. */ #if SQLITE_OS_WINCE dwFlagsAndAttributes |= FILE_FLAG_RANDOM_ACCESS; #endif if( isNT() ){ while( (h = CreateFileW((WCHAR*)zConverted, dwDesiredAccess, dwShareMode, NULL, dwCreationDisposition, dwFlagsAndAttributes, NULL))==INVALID_HANDLE_VALUE && retryIoerr(&cnt) ){} /* isNT() is 1 if SQLITE_OS_WINCE==1, so this else is never executed. ** Since the ASCII version of these Windows API do not exist for WINCE, ** it's important to not reference them for WINCE builds. */ #if SQLITE_OS_WINCE==0 }else{ while( (h = CreateFileA((char*)zConverted, dwDesiredAccess, dwShareMode, NULL, dwCreationDisposition, dwFlagsAndAttributes, NULL))==INVALID_HANDLE_VALUE && retryIoerr(&cnt) ){} #endif } logIoerr(cnt); OSTRACE(("OPEN %d %s 0x%lx %s\n", h, zName, dwDesiredAccess, h==INVALID_HANDLE_VALUE ? "failed" : "ok")); if( h==INVALID_HANDLE_VALUE ){ pFile->lastErrno = GetLastError(); winLogError(SQLITE_CANTOPEN, "winOpen", zUtf8Name); free(zConverted); if( isReadWrite ){ return winOpen(pVfs, zName, id, ((flags|SQLITE_OPEN_READONLY)&~(SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE)), pOutFlags); }else{ return SQLITE_CANTOPEN_BKPT; } } if( pOutFlags ){ if( isReadWrite ){ *pOutFlags = SQLITE_OPEN_READWRITE; }else{ *pOutFlags = SQLITE_OPEN_READONLY; } } memset(pFile, 0, sizeof(*pFile)); pFile->pMethod = &winIoMethod; pFile->h = h; pFile->lastErrno = NO_ERROR; pFile->pVfs = pVfs; pFile->pShm = 0; pFile->zPath = zName; pFile->sectorSize = getSectorSize(pVfs, zUtf8Name); #if SQLITE_OS_WINCE if( isReadWrite && eType==SQLITE_OPEN_MAIN_DB && !winceCreateLock(zName, pFile) ){ CloseHandle(h); free(zConverted); return SQLITE_CANTOPEN_BKPT; } if( isTemp ){ pFile->zDeleteOnClose = zConverted; }else #endif { free(zConverted); } OpenCounter(+1); return rc; } /* ** Delete the named file. ** ** Note that windows does not allow a file to be deleted if some other ** process has it open. Sometimes a virus scanner or indexing program ** will open a journal file shortly after it is created in order to do ** whatever it does. While this other process is holding the ** file open, we will be unable to delete it. To work around this ** problem, we delay 100 milliseconds and try to delete again. Up ** to MX_DELETION_ATTEMPTs deletion attempts are run before giving ** up and returning an error. */ static int winDelete( sqlite3_vfs *pVfs, /* Not used on win32 */ const char *zFilename, /* Name of file to delete */ int syncDir /* Not used on win32 */ ){ int cnt = 0; int rc; void *zConverted; UNUSED_PARAMETER(pVfs); UNUSED_PARAMETER(syncDir); SimulateIOError(return SQLITE_IOERR_DELETE); zConverted = convertUtf8Filename(zFilename); if( zConverted==0 ){ return SQLITE_NOMEM; } if( isNT() ){ rc = 1; while( GetFileAttributesW(zConverted)!=INVALID_FILE_ATTRIBUTES && (rc = DeleteFileW(zConverted))==0 && retryIoerr(&cnt) ){} rc = rc ? SQLITE_OK : SQLITE_ERROR; /* isNT() is 1 if SQLITE_OS_WINCE==1, so this else is never executed. ** Since the ASCII version of these Windows API do not exist for WINCE, ** it's important to not reference them for WINCE builds. */ #if SQLITE_OS_WINCE==0 }else{ rc = 1; while( GetFileAttributesA(zConverted)!=INVALID_FILE_ATTRIBUTES && (rc = DeleteFileA(zConverted))==0 && retryIoerr(&cnt) ){} rc = rc ? SQLITE_OK : SQLITE_ERROR; #endif } if( rc ){ rc = winLogError(SQLITE_IOERR_DELETE, "winDelete", zFilename); }else{ logIoerr(cnt); } free(zConverted); OSTRACE(("DELETE \"%s\" %s\n", zFilename, (rc ? "failed" : "ok" ))); return rc; } /* ** Check the existance and status of a file. */ static int winAccess( sqlite3_vfs *pVfs, /* Not used on win32 */ const char *zFilename, /* Name of file to check */ int flags, /* Type of test to make on this file */ int *pResOut /* OUT: Result */ ){ DWORD attr; int rc = 0; void *zConverted; UNUSED_PARAMETER(pVfs); SimulateIOError( return SQLITE_IOERR_ACCESS; ); zConverted = convertUtf8Filename(zFilename); if( zConverted==0 ){ return SQLITE_NOMEM; } if( isNT() ){ int cnt = 0; WIN32_FILE_ATTRIBUTE_DATA sAttrData; memset(&sAttrData, 0, sizeof(sAttrData)); while( !(rc = GetFileAttributesExW((WCHAR*)zConverted, GetFileExInfoStandard, &sAttrData)) && retryIoerr(&cnt) ){} if( rc ){ /* For an SQLITE_ACCESS_EXISTS query, treat a zero-length file ** as if it does not exist. */ if( flags==SQLITE_ACCESS_EXISTS && sAttrData.nFileSizeHigh==0 && sAttrData.nFileSizeLow==0 ){ attr = INVALID_FILE_ATTRIBUTES; }else{ attr = sAttrData.dwFileAttributes; } }else{ logIoerr(cnt); if( GetLastError()!=ERROR_FILE_NOT_FOUND ){ winLogError(SQLITE_IOERR_ACCESS, "winAccess", zFilename); free(zConverted); return SQLITE_IOERR_ACCESS; }else{ attr = INVALID_FILE_ATTRIBUTES; } } /* isNT() is 1 if SQLITE_OS_WINCE==1, so this else is never executed. ** Since the ASCII version of these Windows API do not exist for WINCE, ** it's important to not reference them for WINCE builds. */ #if SQLITE_OS_WINCE==0 }else{ attr = GetFileAttributesA((char*)zConverted); #endif } free(zConverted); switch( flags ){ case SQLITE_ACCESS_READ: case SQLITE_ACCESS_EXISTS: rc = attr!=INVALID_FILE_ATTRIBUTES; break; case SQLITE_ACCESS_READWRITE: rc = attr!=INVALID_FILE_ATTRIBUTES && (attr & FILE_ATTRIBUTE_READONLY)==0; break; default: assert(!"Invalid flags argument"); } *pResOut = rc; return SQLITE_OK; } /* ** Turn a relative pathname into a full pathname. Write the full ** pathname into zOut[]. zOut[] will be at least pVfs->mxPathname ** bytes in size. */ static int winFullPathname( sqlite3_vfs *pVfs, /* Pointer to vfs object */ const char *zRelative, /* Possibly relative input path */ int nFull, /* Size of output buffer in bytes */ char *zFull /* Output buffer */ ){ #if defined(__CYGWIN__) SimulateIOError( return SQLITE_ERROR ); UNUSED_PARAMETER(nFull); cygwin_conv_to_full_win32_path(zRelative, zFull); return SQLITE_OK; #endif #if SQLITE_OS_WINCE SimulateIOError( return SQLITE_ERROR ); UNUSED_PARAMETER(nFull); /* WinCE has no concept of a relative pathname, or so I am told. */ sqlite3_snprintf(pVfs->mxPathname, zFull, "%s", zRelative); return SQLITE_OK; #endif #if !SQLITE_OS_WINCE && !defined(__CYGWIN__) int nByte; void *zConverted; char *zOut; /* If this path name begins with "/X:", where "X" is any alphabetic ** character, discard the initial "/" from the pathname. */ if( zRelative[0]=='/' && sqlite3Isalpha(zRelative[1]) && zRelative[2]==':' ){ zRelative++; } /* 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. This function could fail if, for example, the ** current working directory has been unlinked. */ SimulateIOError( return SQLITE_ERROR ); UNUSED_PARAMETER(nFull); zConverted = convertUtf8Filename(zRelative); if( isNT() ){ WCHAR *zTemp; nByte = GetFullPathNameW((WCHAR*)zConverted, 0, 0, 0) + 3; zTemp = malloc( nByte*sizeof(zTemp[0]) ); if( zTemp==0 ){ free(zConverted); return SQLITE_NOMEM; } GetFullPathNameW((WCHAR*)zConverted, nByte, zTemp, 0); free(zConverted); zOut = unicodeToUtf8(zTemp); free(zTemp); /* isNT() is 1 if SQLITE_OS_WINCE==1, so this else is never executed. ** Since the ASCII version of these Windows API do not exist for WINCE, ** it's important to not reference them for WINCE builds. */ #if SQLITE_OS_WINCE==0 }else{ char *zTemp; nByte = GetFullPathNameA((char*)zConverted, 0, 0, 0) + 3; zTemp = malloc( nByte*sizeof(zTemp[0]) ); if( zTemp==0 ){ free(zConverted); return SQLITE_NOMEM; } GetFullPathNameA((char*)zConverted, nByte, zTemp, 0); free(zConverted); zOut = sqlite3_win32_mbcs_to_utf8(zTemp); free(zTemp); #endif } if( zOut ){ sqlite3_snprintf(pVfs->mxPathname, zFull, "%s", zOut); free(zOut); return SQLITE_OK; }else{ return SQLITE_NOMEM; } #endif } /* ** Get the sector size of the device used to store ** file. */ static int getSectorSize( sqlite3_vfs *pVfs, const char *zRelative /* UTF-8 file name */ ){ DWORD bytesPerSector = SQLITE_DEFAULT_SECTOR_SIZE; /* GetDiskFreeSpace is not supported under WINCE */ #if SQLITE_OS_WINCE UNUSED_PARAMETER(pVfs); UNUSED_PARAMETER(zRelative); #else char zFullpath[MAX_PATH+1]; int rc; DWORD dwRet = 0; DWORD dwDummy; /* ** We need to get the full path name of the file ** to get the drive letter to look up the sector ** size. */ SimulateIOErrorBenign(1); rc = winFullPathname(pVfs, zRelative, MAX_PATH, zFullpath); SimulateIOErrorBenign(0); if( rc == SQLITE_OK ) { void *zConverted = convertUtf8Filename(zFullpath); if( zConverted ){ if( isNT() ){ /* trim path to just drive reference */ WCHAR *p = zConverted; for(;*p;p++){ if( *p == '\\' ){ *p = '\0'; break; } } dwRet = GetDiskFreeSpaceW((WCHAR*)zConverted, &dwDummy, &bytesPerSector, &dwDummy, &dwDummy); }else{ /* trim path to just drive reference */ char *p = (char *)zConverted; for(;*p;p++){ if( *p == '\\' ){ *p = '\0'; break; } } dwRet = GetDiskFreeSpaceA((char*)zConverted, &dwDummy, &bytesPerSector, &dwDummy, &dwDummy); } free(zConverted); } if( !dwRet ){ bytesPerSector = SQLITE_DEFAULT_SECTOR_SIZE; } } #endif return (int) bytesPerSector; } #ifndef SQLITE_OMIT_LOAD_EXTENSION /* ** Interfaces for opening a shared library, finding entry points ** within the shared library, and closing the shared library. */ /* ** Interfaces for opening a shared library, finding entry points ** within the shared library, and closing the shared library. */ static void *winDlOpen(sqlite3_vfs *pVfs, const char *zFilename){ HANDLE h; void *zConverted = convertUtf8Filename(zFilename); UNUSED_PARAMETER(pVfs); if( zConverted==0 ){ return 0; } if( isNT() ){ h = LoadLibraryW((WCHAR*)zConverted); /* isNT() is 1 if SQLITE_OS_WINCE==1, so this else is never executed. ** Since the ASCII version of these Windows API do not exist for WINCE, ** it's important to not reference them for WINCE builds. */ #if SQLITE_OS_WINCE==0 }else{ h = LoadLibraryA((char*)zConverted); #endif } free(zConverted); return (void*)h; } static void winDlError(sqlite3_vfs *pVfs, int nBuf, char *zBufOut){ UNUSED_PARAMETER(pVfs); getLastErrorMsg(nBuf, zBufOut); } void (*winDlSym(sqlite3_vfs *pVfs, void *pHandle, const char *zSymbol))(void){ UNUSED_PARAMETER(pVfs); #if SQLITE_OS_WINCE /* The GetProcAddressA() routine is only available on wince. */ return (void(*)(void))GetProcAddressA((HANDLE)pHandle, zSymbol); #else /* All other windows platforms expect GetProcAddress() to take ** an Ansi string regardless of the _UNICODE setting */ return (void(*)(void))GetProcAddress((HANDLE)pHandle, zSymbol); #endif } void winDlClose(sqlite3_vfs *pVfs, void *pHandle){ UNUSED_PARAMETER(pVfs); FreeLibrary((HANDLE)pHandle); } #else /* if SQLITE_OMIT_LOAD_EXTENSION is defined: */ #define winDlOpen 0 #define winDlError 0 #define winDlSym 0 #define winDlClose 0 #endif /* ** Write up to nBuf bytes of randomness into zBuf. */ static int winRandomness(sqlite3_vfs *pVfs, int nBuf, char *zBuf){ int n = 0; UNUSED_PARAMETER(pVfs); #if defined(SQLITE_TEST) n = nBuf; memset(zBuf, 0, nBuf); #else if( sizeof(SYSTEMTIME)<=nBuf-n ){ SYSTEMTIME x; GetSystemTime(&x); memcpy(&zBuf[n], &x, sizeof(x)); n += sizeof(x); } if( sizeof(DWORD)<=nBuf-n ){ DWORD pid = GetCurrentProcessId(); memcpy(&zBuf[n], &pid, sizeof(pid)); n += sizeof(pid); } if( sizeof(DWORD)<=nBuf-n ){ DWORD cnt = GetTickCount(); memcpy(&zBuf[n], &cnt, sizeof(cnt)); n += sizeof(cnt); } if( sizeof(LARGE_INTEGER)<=nBuf-n ){ LARGE_INTEGER i; QueryPerformanceCounter(&i); memcpy(&zBuf[n], &i, sizeof(i)); n += sizeof(i); } #endif return n; } /* ** Sleep for a little while. Return the amount of time slept. */ static int winSleep(sqlite3_vfs *pVfs, int microsec){ Sleep((microsec+999)/1000); UNUSED_PARAMETER(pVfs); return ((microsec+999)/1000)*1000; } /* ** The following variable, if set to a non-zero value, is interpreted as ** the number of seconds since 1970 and is used to set the result of ** sqlite3OsCurrentTime() during testing. */ #ifdef SQLITE_TEST int sqlite3_current_time = 0; /* Fake system time in seconds since 1970. */ #endif /* ** Find the current time (in Universal Coordinated Time). Write into *piNow ** the current time and date as a Julian Day number times 86_400_000. In ** other words, write into *piNow the number of milliseconds since the Julian ** epoch of noon in Greenwich on November 24, 4714 B.C according to the ** proleptic Gregorian calendar. ** ** On success, return 0. Return 1 if the time and date cannot be found. */ static int winCurrentTimeInt64(sqlite3_vfs *pVfs, sqlite3_int64 *piNow){ /* FILETIME structure is a 64-bit value representing the number of 100-nanosecond intervals since January 1, 1601 (= JD 2305813.5). */ FILETIME ft; static const sqlite3_int64 winFiletimeEpoch = 23058135*(sqlite3_int64)8640000; #ifdef SQLITE_TEST static const sqlite3_int64 unixEpoch = 24405875*(sqlite3_int64)8640000; #endif /* 2^32 - to avoid use of LL and warnings in gcc */ static const sqlite3_int64 max32BitValue = (sqlite3_int64)2000000000 + (sqlite3_int64)2000000000 + (sqlite3_int64)294967296; #if SQLITE_OS_WINCE SYSTEMTIME time; GetSystemTime(&time); /* if SystemTimeToFileTime() fails, it returns zero. */ if (!SystemTimeToFileTime(&time,&ft)){ return 1; } #else GetSystemTimeAsFileTime( &ft ); #endif *piNow = winFiletimeEpoch + ((((sqlite3_int64)ft.dwHighDateTime)*max32BitValue) + (sqlite3_int64)ft.dwLowDateTime)/(sqlite3_int64)10000; #ifdef SQLITE_TEST if( sqlite3_current_time ){ *piNow = 1000*(sqlite3_int64)sqlite3_current_time + unixEpoch; } #endif UNUSED_PARAMETER(pVfs); return 0; } /* ** Find the current time (in Universal Coordinated Time). Write the ** current time and date as a Julian Day number into *prNow and ** return 0. Return 1 if the time and date cannot be found. */ int winCurrentTime(sqlite3_vfs *pVfs, double *prNow){ int rc; sqlite3_int64 i; rc = winCurrentTimeInt64(pVfs, &i); if( !rc ){ *prNow = i/86400000.0; } return rc; } /* ** The idea is that this function works like a combination of ** GetLastError() and FormatMessage() on windows (or errno and ** strerror_r() on unix). After an error is returned by an OS ** function, SQLite calls this function with zBuf pointing to ** a buffer of nBuf bytes. The OS layer should populate the ** buffer with a nul-terminated UTF-8 encoded error message ** describing the last IO error to have occurred within the calling ** thread. ** ** If the error message is too large for the supplied buffer, ** it should be truncated. The return value of xGetLastError ** is zero if the error message fits in the buffer, or non-zero ** otherwise (if the message was truncated). If non-zero is returned, ** then it is not necessary to include the nul-terminator character ** in the output buffer. ** ** Not supplying an error message will have no adverse effect ** on SQLite. It is fine to have an implementation that never ** returns an error message: ** ** int xGetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){ ** assert(zBuf[0]=='\0'); ** return 0; ** } ** ** However if an error message is supplied, it will be incorporated ** by sqlite into the error message available to the user using ** sqlite3_errmsg(), possibly making IO errors easier to debug. */ static int winGetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){ UNUSED_PARAMETER(pVfs); return getLastErrorMsg(nBuf, zBuf); } /* ** Initialize and deinitialize the operating system interface. */ int sqlite3_os_init(void){ static sqlite3_vfs winVfs = { 3, /* iVersion */ sizeof(winFile), /* szOsFile */ MAX_PATH, /* mxPathname */ 0, /* pNext */ "win32", /* zName */ 0, /* pAppData */ winOpen, /* xOpen */ winDelete, /* xDelete */ winAccess, /* xAccess */ winFullPathname, /* xFullPathname */ winDlOpen, /* xDlOpen */ winDlError, /* xDlError */ winDlSym, /* xDlSym */ winDlClose, /* xDlClose */ winRandomness, /* xRandomness */ winSleep, /* xSleep */ winCurrentTime, /* xCurrentTime */ winGetLastError, /* xGetLastError */ winCurrentTimeInt64, /* xCurrentTimeInt64 */ 0, /* xSetSystemCall */ 0, /* xGetSystemCall */ 0, /* xNextSystemCall */ }; #ifndef SQLITE_OMIT_WAL /* get memory map allocation granularity */ memset(&winSysInfo, 0, sizeof(SYSTEM_INFO)); GetSystemInfo(&winSysInfo); assert(winSysInfo.dwAllocationGranularity > 0); #endif sqlite3_vfs_register(&winVfs, 1); return SQLITE_OK; } int sqlite3_os_end(void){ return SQLITE_OK; } #endif /* SQLITE_OS_WIN */