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Diffstat (limited to 'third_party/sqlite/os_win.c')
| -rw-r--r-- | third_party/sqlite/os_win.c | 1758 |
1 files changed, 1758 insertions, 0 deletions
diff --git a/third_party/sqlite/os_win.c b/third_party/sqlite/os_win.c new file mode 100644 index 0000000..9ebb9dc --- /dev/null +++ b/third_party/sqlite/os_win.c @@ -0,0 +1,1758 @@ +/* +** 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" +#include "os.h" +#if OS_WIN /* This file is used for windows only */ + +#include <winbase.h> + +#ifdef __CYGWIN__ +# include <sys/cygwin.h> +#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" + +/* +** Determine if we are dealing with WindowsCE - which has a much +** reduced API. +*/ +#if defined(_WIN32_WCE) +# define OS_WINCE 1 +# define AreFileApisANSI() 1 +#else +# define OS_WINCE 0 +#endif + +/* +** WinCE lacks native support for file locking so we have to fake it +** with some code of our own. +*/ +#if 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 OsFile specific to the win32 +** portability layer. +*/ +typedef struct winFile winFile; +struct winFile { + IoMethod const *pMethod;/* Must be first */ + HANDLE h; /* Handle for accessing the file */ + unsigned char locktype; /* Type of lock currently held on this file */ + short sharedLockByte; /* Randomly chosen byte used as a shared lock */ +#if 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 +}; + + +/* +** Do not include any of the File I/O interface procedures if the +** SQLITE_OMIT_DISKIO macro is defined (indicating that there database +** will be in-memory only) +*/ +#ifndef SQLITE_OMIT_DISKIO + +/* +** 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. +*/ +int sqlite3_os_type = 0; + +/* +** 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 win 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 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 /* OS_WINCE */ + +/* +** Convert a UTF-8 string to microsoft unicode (UTF-16?). +** +** Space to hold the returned string is obtained from sqliteMalloc. +*/ +static WCHAR *utf8ToUnicode(const char *zFilename){ + int nChar; + WCHAR *zWideFilename; + + nChar = MultiByteToWideChar(CP_UTF8, 0, zFilename, -1, NULL, 0); + zWideFilename = sqliteMalloc( nChar*sizeof(zWideFilename[0]) ); + if( zWideFilename==0 ){ + return 0; + } + nChar = MultiByteToWideChar(CP_UTF8, 0, zFilename, -1, zWideFilename, nChar); + if( nChar==0 ){ + sqliteFree(zWideFilename); + zWideFilename = 0; + } + return zWideFilename; +} + +/* +** Convert microsoft unicode to UTF-8. Space to hold the returned string is +** obtained from sqliteMalloc(). +*/ +static char *unicodeToUtf8(const WCHAR *zWideFilename){ + int nByte; + char *zFilename; + + nByte = WideCharToMultiByte(CP_UTF8, 0, zWideFilename, -1, 0, 0, 0, 0); + zFilename = sqliteMalloc( nByte ); + if( zFilename==0 ){ + return 0; + } + nByte = WideCharToMultiByte(CP_UTF8, 0, zWideFilename, -1, zFilename, nByte, + 0, 0); + if( nByte == 0 ){ + sqliteFree(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 sqliteMalloc. +*/ +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 = sqliteMalloc( nByte*sizeof(zMbcsFilename[0]) ); + if( zMbcsFilename==0 ){ + return 0; + } + nByte = MultiByteToWideChar(codepage, 0, zFilename, -1, zMbcsFilename, nByte); + if( nByte==0 ){ + sqliteFree(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 +** sqliteMalloc(). +*/ +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 = sqliteMalloc( nByte ); + if( zFilename==0 ){ + return 0; + } + nByte = WideCharToMultiByte(codepage, 0, zWideFilename, -1, zFilename, nByte, + 0, 0); + if( nByte == 0 ){ + sqliteFree(zFilename); + zFilename = 0; + } + return zFilename; +} + +/* +** Convert multibyte character string to UTF-8. Space to hold the +** returned string is obtained from sqliteMalloc(). +*/ +static char *mbcsToUtf8(const char *zFilename){ + char *zFilenameUtf8; + WCHAR *zTmpWide; + + zTmpWide = mbcsToUnicode(zFilename); + if( zTmpWide==0 ){ + return 0; + } + zFilenameUtf8 = unicodeToUtf8(zTmpWide); + sqliteFree(zTmpWide); + return zFilenameUtf8; +} + +/* +** Convert UTF-8 to multibyte character string. Space to hold the +** returned string is obtained from sqliteMalloc(). +*/ +static char *utf8ToMbcs(const char *zFilename){ + char *zFilenameMbcs; + WCHAR *zTmpWide; + + zTmpWide = utf8ToUnicode(zFilename); + if( zTmpWide==0 ){ + return 0; + } + zFilenameMbcs = unicodeToMbcs(zTmpWide); + sqliteFree(zTmpWide); + return zFilenameMbcs; +} + +#if OS_WINCE +/************************************************************************* +** This section contains code for WinCE only. +*/ +/* +** WindowsCE does not have a localtime() function. So create a +** substitute. +*/ +#include <time.h> +struct tm *__cdecl localtime(const time_t *t) +{ + static struct tm y; + FILETIME uTm, lTm; + SYSTEMTIME pTm; + i64 t64; + t64 = *t; + t64 = (t64 + 11644473600)*10000000; + uTm.dwLowDateTime = t64 & 0xFFFFFFFF; + uTm.dwHighDateTime= 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)[-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){ + sqliteFree(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; + } + + sqliteFree(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){ + 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); + + if( pFile->zDeleteOnClose ){ + DeleteFileW(pFile->zDeleteOnClose); + sqliteFree(pFile->zDeleteOnClose); + pFile->zDeleteOnClose = 0; + } + + /* 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; + + if (!pFile->hMutex) return TRUE; + winceMutexAcquire(pFile->hMutex); + + /* Wanting an exclusive lock? */ + if (dwFileOffsetLow == SHARED_FIRST + && nNumberOfBytesToLockLow == 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 >= SHARED_FIRST && + dwFileOffsetLow < SHARED_FIRST + SHARED_SIZE) && + 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 == 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 == 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; + + if (!pFile->hMutex) return TRUE; + winceMutexAcquire(pFile->hMutex); + + /* Releasing a reader lock or an exclusive lock */ + if (dwFileOffsetLow >= SHARED_FIRST && + dwFileOffsetLow < SHARED_FIRST + SHARED_SIZE){ + /* Did we have an exclusive lock? */ + if (pFile->local.bExclusive){ + pFile->local.bExclusive = FALSE; + pFile->shared->bExclusive = FALSE; + bReturn = TRUE; + } + + /* Did we just have a reader lock? */ + else if (pFile->local.nReaders){ + pFile->local.nReaders --; + if (pFile->local.nReaders == 0) + { + pFile->shared->nReaders --; + } + bReturn = TRUE; + } + } + + /* Releasing a pending lock */ + else if (dwFileOffsetLow == 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 == 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 +){ + /* If the caller wants a shared read lock, forward this call + ** to winceLockFile */ + if (lpOverlapped->Offset == SHARED_FIRST && + dwFlags == 1 && + nNumberOfBytesToLockLow == SHARED_SIZE){ + return winceLockFile(phFile, SHARED_FIRST, 0, 1, 0); + } + return FALSE; +} +/* +** End of the special code for wince +*****************************************************************************/ +#endif /* OS_WINCE */ + +/* +** Convert a UTF-8 filename into whatever form the underlying +** operating system wants filenames in. Space to hold the result +** is obtained from sqliteMalloc and must be freed by the calling +** function. +*/ +static void *convertUtf8Filename(const char *zFilename){ + void *zConverted = 0; + if( isNT() ){ + zConverted = utf8ToUnicode(zFilename); + }else{ + zConverted = utf8ToMbcs(zFilename); + } + /* caller will handle out of memory */ + return zConverted; +} + +/* +** 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 is 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. +*/ +#define MX_DELETION_ATTEMPTS 3 +int sqlite3WinDelete(const char *zFilename){ + int cnt = 0; + int rc; + void *zConverted = convertUtf8Filename(zFilename); + if( zConverted==0 ){ + return SQLITE_NOMEM; + } + SimulateIOError(return SQLITE_IOERR_DELETE); + if( isNT() ){ + do{ + rc = DeleteFileW(zConverted); + }while( rc==0 && GetFileAttributesW(zConverted)!=0xffffffff + && cnt++ < MX_DELETION_ATTEMPTS && (Sleep(100), 1) ); + }else{ +#if OS_WINCE + return SQLITE_NOMEM; +#else + do{ + rc = DeleteFileA(zConverted); + }while( rc==0 && GetFileAttributesA(zConverted)!=0xffffffff + && cnt++ < MX_DELETION_ATTEMPTS && (Sleep(100), 1) ); +#endif + } + sqliteFree(zConverted); + OSTRACE2("DELETE \"%s\"\n", zFilename); + return rc!=0 ? SQLITE_OK : SQLITE_IOERR; +} + +/* +** Return TRUE if the named file exists. +*/ +int sqlite3WinFileExists(const char *zFilename){ + int exists = 0; + void *zConverted = convertUtf8Filename(zFilename); + if( zConverted==0 ){ + return SQLITE_NOMEM; + } + if( isNT() ){ + exists = GetFileAttributesW((WCHAR*)zConverted) != 0xffffffff; + }else{ +#if OS_WINCE + return SQLITE_NOMEM; +#else + exists = GetFileAttributesA((char*)zConverted) != 0xffffffff; +#endif + } + sqliteFree(zConverted); + return exists; +} + +/* Forward declaration */ +static int allocateWinFile(winFile *pInit, OsFile **pId); + +/* +** Attempt to open a file for both reading and writing. If that +** fails, try opening it read-only. If the file does not exist, +** try to create it. +** +** On success, a handle for the open file is written to *id +** and *pReadonly is set to 0 if the file was opened for reading and +** writing or 1 if the file was opened read-only. The function returns +** SQLITE_OK. +** +** On failure, the function returns SQLITE_CANTOPEN and leaves +** *id and *pReadonly unchanged. +*/ +int sqlite3WinOpenReadWrite( + const char *zFilename, + OsFile **pId, + int *pReadonly +){ + winFile f; + HANDLE h; + void *zConverted = convertUtf8Filename(zFilename); + if( zConverted==0 ){ + return SQLITE_NOMEM; + } + assert( *pId==0 ); + + if( isNT() ){ + h = CreateFileW((WCHAR*)zConverted, + GENERIC_READ | GENERIC_WRITE, + FILE_SHARE_READ | FILE_SHARE_WRITE, + NULL, + OPEN_ALWAYS, + FILE_ATTRIBUTE_NORMAL | FILE_FLAG_RANDOM_ACCESS, + NULL + ); + if( h==INVALID_HANDLE_VALUE ){ + h = CreateFileW((WCHAR*)zConverted, + GENERIC_READ, + FILE_SHARE_READ | FILE_SHARE_WRITE, + NULL, + OPEN_ALWAYS, + FILE_ATTRIBUTE_NORMAL | FILE_FLAG_RANDOM_ACCESS, + NULL + ); + if( h==INVALID_HANDLE_VALUE ){ + sqliteFree(zConverted); + return SQLITE_CANTOPEN; + } + *pReadonly = 1; + }else{ + *pReadonly = 0; + } +#if OS_WINCE + if (!winceCreateLock(zFilename, &f)){ + CloseHandle(h); + sqliteFree(zConverted); + return SQLITE_CANTOPEN; + } +#endif + }else{ +#if OS_WINCE + return SQLITE_NOMEM; +#else + h = CreateFileA((char*)zConverted, + GENERIC_READ | GENERIC_WRITE, + FILE_SHARE_READ | FILE_SHARE_WRITE, + NULL, + OPEN_ALWAYS, + FILE_ATTRIBUTE_NORMAL | FILE_FLAG_RANDOM_ACCESS, + NULL + ); + if( h==INVALID_HANDLE_VALUE ){ + h = CreateFileA((char*)zConverted, + GENERIC_READ, + FILE_SHARE_READ | FILE_SHARE_WRITE, + NULL, + OPEN_ALWAYS, + FILE_ATTRIBUTE_NORMAL | FILE_FLAG_RANDOM_ACCESS, + NULL + ); + if( h==INVALID_HANDLE_VALUE ){ + sqliteFree(zConverted); + return SQLITE_CANTOPEN; + } + *pReadonly = 1; + }else{ + *pReadonly = 0; + } +#endif /* OS_WINCE */ + } + + sqliteFree(zConverted); + + f.h = h; +#if OS_WINCE + f.zDeleteOnClose = 0; +#endif + OSTRACE3("OPEN R/W %d \"%s\"\n", h, zFilename); + return allocateWinFile(&f, pId); +} + + +/* +** Attempt to open a new file for exclusive access by this process. +** The file will be opened for both reading and writing. To avoid +** a potential security problem, we do not allow the file to have +** previously existed. Nor do we allow the file to be a symbolic +** link. +** +** If delFlag is true, then make arrangements to automatically delete +** the file when it is closed. +** +** On success, write the file handle into *id and return SQLITE_OK. +** +** On failure, return SQLITE_CANTOPEN. +** +** Sometimes if we have just deleted a prior journal file, windows +** will fail to open a new one because there is a "pending delete". +** To work around this bug, we pause for 100 milliseconds and attempt +** a second open after the first one fails. The whole operation only +** fails if both open attempts are unsuccessful. +*/ +int sqlite3WinOpenExclusive(const char *zFilename, OsFile **pId, int delFlag){ + winFile f; + HANDLE h; + DWORD fileflags; + void *zConverted = convertUtf8Filename(zFilename); + if( zConverted==0 ){ + return SQLITE_NOMEM; + } + assert( *pId == 0 ); + fileflags = FILE_FLAG_RANDOM_ACCESS; +#if !OS_WINCE + if( delFlag ){ + fileflags |= FILE_ATTRIBUTE_TEMPORARY | FILE_FLAG_DELETE_ON_CLOSE; + } +#endif + if( isNT() ){ + int cnt = 0; + do{ + h = CreateFileW((WCHAR*)zConverted, + GENERIC_READ | GENERIC_WRITE, + 0, + NULL, + CREATE_ALWAYS, + fileflags, + NULL + ); + }while( h==INVALID_HANDLE_VALUE && cnt++ < 2 && (Sleep(100), 1) ); + }else{ +#if OS_WINCE + return SQLITE_NOMEM; +#else + int cnt = 0; + do{ + h = CreateFileA((char*)zConverted, + GENERIC_READ | GENERIC_WRITE, + 0, + NULL, + CREATE_ALWAYS, + fileflags, + NULL + ); + }while( h==INVALID_HANDLE_VALUE && cnt++ < 2 && (Sleep(100), 1) ); +#endif /* OS_WINCE */ + } +#if OS_WINCE + if( delFlag && h!=INVALID_HANDLE_VALUE ){ + f.zDeleteOnClose = zConverted; + zConverted = 0; + } + f.hMutex = NULL; +#endif + sqliteFree(zConverted); + if( h==INVALID_HANDLE_VALUE ){ + return SQLITE_CANTOPEN; + } + f.h = h; + OSTRACE3("OPEN EX %d \"%s\"\n", h, zFilename); + return allocateWinFile(&f, pId); +} + +/* +** Attempt to open a new file for read-only access. +** +** On success, write the file handle into *id and return SQLITE_OK. +** +** On failure, return SQLITE_CANTOPEN. +*/ +int sqlite3WinOpenReadOnly(const char *zFilename, OsFile **pId){ + winFile f; + HANDLE h; + void *zConverted = convertUtf8Filename(zFilename); + if( zConverted==0 ){ + return SQLITE_NOMEM; + } + assert( *pId==0 ); + if( isNT() ){ + h = CreateFileW((WCHAR*)zConverted, + GENERIC_READ, + 0, + NULL, + OPEN_EXISTING, + FILE_ATTRIBUTE_NORMAL | FILE_FLAG_RANDOM_ACCESS, + NULL + ); + }else{ +#if OS_WINCE + return SQLITE_NOMEM; +#else + h = CreateFileA((char*)zConverted, + GENERIC_READ, + 0, + NULL, + OPEN_EXISTING, + FILE_ATTRIBUTE_NORMAL | FILE_FLAG_RANDOM_ACCESS, + NULL + ); +#endif + } + sqliteFree(zConverted); + if( h==INVALID_HANDLE_VALUE ){ + return SQLITE_CANTOPEN; + } + f.h = h; +#if OS_WINCE + f.zDeleteOnClose = 0; + f.hMutex = NULL; +#endif + OSTRACE3("OPEN RO %d \"%s\"\n", h, zFilename); + return allocateWinFile(&f, pId); +} + +/* +** Attempt to open a file descriptor for the directory that contains a +** file. This file descriptor can be used to fsync() the directory +** in order to make sure the creation of a new file is actually written +** to disk. +** +** This routine is only meaningful for Unix. It is a no-op under +** windows since windows does not support hard links. +** +** On success, a handle for a previously open file is at *id is +** updated with the new directory file descriptor and SQLITE_OK is +** returned. +** +** On failure, the function returns SQLITE_CANTOPEN and leaves +** *id unchanged. +*/ +static int winOpenDirectory( + OsFile *id, + const char *zDirname +){ + return SQLITE_OK; +} + +/* +** Create a temporary file name in zBuf. zBuf must be big enough to +** hold at least SQLITE_TEMPNAME_SIZE characters. +*/ +int sqlite3WinTempFileName(char *zBuf){ + static char zChars[] = + "abcdefghijklmnopqrstuvwxyz" + "ABCDEFGHIJKLMNOPQRSTUVWXYZ" + "0123456789"; + int i, j; + char zTempPath[SQLITE_TEMPNAME_SIZE]; + if( sqlite3_temp_directory ){ + strncpy(zTempPath, sqlite3_temp_directory, SQLITE_TEMPNAME_SIZE-30); + zTempPath[SQLITE_TEMPNAME_SIZE-30] = 0; + }else if( isNT() ){ + char *zMulti; + WCHAR zWidePath[SQLITE_TEMPNAME_SIZE]; + GetTempPathW(SQLITE_TEMPNAME_SIZE-30, zWidePath); + zMulti = unicodeToUtf8(zWidePath); + if( zMulti ){ + strncpy(zTempPath, zMulti, SQLITE_TEMPNAME_SIZE-30); + zTempPath[SQLITE_TEMPNAME_SIZE-30] = 0; + sqliteFree(zMulti); + }else{ + return SQLITE_NOMEM; + } + }else{ + char *zUtf8; + char zMbcsPath[SQLITE_TEMPNAME_SIZE]; + GetTempPathA(SQLITE_TEMPNAME_SIZE-30, zMbcsPath); + zUtf8 = mbcsToUtf8(zMbcsPath); + if( zUtf8 ){ + strncpy(zTempPath, zUtf8, SQLITE_TEMPNAME_SIZE-30); + zTempPath[SQLITE_TEMPNAME_SIZE-30] = 0; + sqliteFree(zUtf8); + }else{ + return SQLITE_NOMEM; + } + } + for(i=strlen(zTempPath); i>0 && zTempPath[i-1]=='\\'; i--){} + zTempPath[i] = 0; + for(;;){ + sqlite3_snprintf(SQLITE_TEMPNAME_SIZE, zBuf, + "%s\\"TEMP_FILE_PREFIX, zTempPath); + j = strlen(zBuf); + sqlite3Randomness(15, &zBuf[j]); + for(i=0; i<15; i++, j++){ + zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ]; + } + zBuf[j] = 0; + if( !sqlite3OsFileExists(zBuf) ) break; + } + OSTRACE2("TEMP FILENAME: %s\n", zBuf); + return SQLITE_OK; +} + +/* +** 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(OsFile **pId){ + winFile *pFile; + int rc = 1; + if( pId && (pFile = (winFile*)*pId)!=0 ){ + int rc, cnt = 0; + OSTRACE2("CLOSE %d\n", pFile->h); + do{ + rc = CloseHandle(pFile->h); + }while( rc==0 && cnt++ < MX_CLOSE_ATTEMPT && (Sleep(100), 1) ); +#if OS_WINCE + winceDestroyLock(pFile); +#endif + OpenCounter(-1); + sqliteFree(pFile); + *pId = 0; + } + return rc ? SQLITE_OK : SQLITE_IOERR; +} + +/* +** 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(OsFile *id, void *pBuf, int amt){ + DWORD got; + assert( id!=0 ); + SimulateIOError(return SQLITE_IOERR_READ); + OSTRACE3("READ %d lock=%d\n", ((winFile*)id)->h, ((winFile*)id)->locktype); + if( !ReadFile(((winFile*)id)->h, pBuf, amt, &got, 0) ){ + return SQLITE_IOERR_READ; + } + if( got==(DWORD)amt ){ + return SQLITE_OK; + }else{ + memset(&((char*)pBuf)[got], 0, amt-got); + return SQLITE_IOERR_SHORT_READ; + } +} + +/* +** Write data from a buffer into a file. Return SQLITE_OK on success +** or some other error code on failure. +*/ +static int winWrite(OsFile *id, const void *pBuf, int amt){ + int rc = 0; + DWORD wrote; + assert( id!=0 ); + SimulateIOError(return SQLITE_IOERR_READ); + SimulateDiskfullError(return SQLITE_FULL); + OSTRACE3("WRITE %d lock=%d\n", ((winFile*)id)->h, ((winFile*)id)->locktype); + assert( amt>0 ); + while( amt>0 && (rc = WriteFile(((winFile*)id)->h, pBuf, amt, &wrote, 0))!=0 + && wrote>0 ){ + amt -= wrote; + pBuf = &((char*)pBuf)[wrote]; + } + if( !rc || amt>(int)wrote ){ + return SQLITE_FULL; + } + return SQLITE_OK; +} + +/* +** Some microsoft compilers lack this definition. +*/ +#ifndef INVALID_SET_FILE_POINTER +# define INVALID_SET_FILE_POINTER ((DWORD)-1) +#endif + +/* +** Move the read/write pointer in a file. +*/ +static int winSeek(OsFile *id, i64 offset){ + LONG upperBits = offset>>32; + LONG lowerBits = offset & 0xffffffff; + DWORD rc; + assert( id!=0 ); +#ifdef SQLITE_TEST + if( offset ) SimulateDiskfullError(return SQLITE_FULL); +#endif + rc = SetFilePointer(((winFile*)id)->h, lowerBits, &upperBits, FILE_BEGIN); + OSTRACE3("SEEK %d %lld\n", ((winFile*)id)->h, offset); + if( rc==INVALID_SET_FILE_POINTER && GetLastError()!=NO_ERROR ){ + return SQLITE_FULL; + } + return SQLITE_OK; +} + +/* +** Make sure all writes to a particular file are committed to disk. +*/ +static int winSync(OsFile *id, int dataOnly){ + assert( id!=0 ); + OSTRACE3("SYNC %d lock=%d\n", ((winFile*)id)->h, ((winFile*)id)->locktype); + if( FlushFileBuffers(((winFile*)id)->h) ){ + return SQLITE_OK; + }else{ + return SQLITE_IOERR; + } +} + +/* +** Sync the directory zDirname. This is a no-op on operating systems other +** than UNIX. +*/ +int sqlite3WinSyncDirectory(const char *zDirname){ + SimulateIOError(return SQLITE_IOERR_READ); + return SQLITE_OK; +} + +/* +** Truncate an open file to a specified size +*/ +static int winTruncate(OsFile *id, i64 nByte){ + LONG upperBits = nByte>>32; + assert( id!=0 ); + OSTRACE3("TRUNCATE %d %lld\n", ((winFile*)id)->h, nByte); + SimulateIOError(return SQLITE_IOERR_TRUNCATE); + SetFilePointer(((winFile*)id)->h, nByte, &upperBits, FILE_BEGIN); + SetEndOfFile(((winFile*)id)->h); + return SQLITE_OK; +} + +/* +** Determine the current size of a file in bytes +*/ +static int winFileSize(OsFile *id, i64 *pSize){ + DWORD upperBits, lowerBits; + assert( id!=0 ); + SimulateIOError(return SQLITE_IOERR_FSTAT); + lowerBits = GetFileSize(((winFile*)id)->h, &upperBits); + *pSize = (((i64)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 *id){ + int res; + if( isNT() ){ + OVERLAPPED ovlp; + ovlp.Offset = SHARED_FIRST; + ovlp.OffsetHigh = 0; + ovlp.hEvent = 0; + res = LockFileEx(id->h, LOCKFILE_FAIL_IMMEDIATELY, 0, SHARED_SIZE,0,&ovlp); + }else{ + int lk; + sqlite3Randomness(sizeof(lk), &lk); + id->sharedLockByte = (lk & 0x7fffffff)%(SHARED_SIZE - 1); + res = LockFile(id->h, SHARED_FIRST+id->sharedLockByte, 0, 1, 0); + } + return res; +} + +/* +** Undo a readlock +*/ +static int unlockReadLock(winFile *pFile){ + int res; + if( isNT() ){ + res = UnlockFile(pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0); + }else{ + res = UnlockFile(pFile->h, SHARED_FIRST + pFile->sharedLockByte, 0, 1, 0); + } + return res; +} + +#ifndef SQLITE_OMIT_PAGER_PRAGMAS +/* +** Check that a given pathname is a directory and is writable +** +*/ +int sqlite3WinIsDirWritable(char *zDirname){ + int fileAttr; + void *zConverted; + if( zDirname==0 ) return 0; + if( !isNT() && strlen(zDirname)>MAX_PATH ) return 0; + + zConverted = convertUtf8Filename(zDirname); + if( zConverted==0 ){ + return SQLITE_NOMEM; + } + if( isNT() ){ + fileAttr = GetFileAttributesW((WCHAR*)zConverted); + }else{ +#if OS_WINCE + return 0; +#else + fileAttr = GetFileAttributesA((char*)zConverted); +#endif + } + sqliteFree(zConverted); + if( fileAttr == 0xffffffff ) return 0; + if( (fileAttr & FILE_ATTRIBUTE_DIRECTORY) != FILE_ATTRIBUTE_DIRECTORY ){ + return 0; + } + return 1; +} +#endif /* SQLITE_OMIT_PAGER_PRAGMAS */ + +/* +** 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(OsFile *id, int locktype){ + int rc = SQLITE_OK; /* Return code from subroutines */ + int res = 1; /* Result of a windows lock call */ + int newLocktype; /* Set id->locktype to this value before exiting */ + int gotPendingLock = 0;/* True if we acquired a PENDING lock this time */ + winFile *pFile = (winFile*)id; + + assert( pFile!=0 ); + OSTRACE5("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. + */ + OSTRACE2("could not get a PENDING lock. cnt=%d\n", cnt); + Sleep(1); + } + gotPendingLock = res; + } + + /* Acquire a shared lock + */ + if( locktype==SHARED_LOCK && res ){ + assert( pFile->locktype==NO_LOCK ); + res = getReadLock(pFile); + if( res ){ + newLocktype = SHARED_LOCK; + } + } + + /* 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; + } + } + + /* 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); + OSTRACE2("unreadlock = %d\n", res); + res = LockFile(pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0); + if( res ){ + newLocktype = EXCLUSIVE_LOCK; + }else{ + OSTRACE2("error-code = %d\n", GetLastError()); + 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{ + OSTRACE4("LOCK FAILED %d trying for %d but got %d\n", pFile->h, + locktype, newLocktype); + rc = SQLITE_BUSY; + } + pFile->locktype = 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(OsFile *id){ + int rc; + winFile *pFile = (winFile*)id; + assert( pFile!=0 ); + if( pFile->locktype>=RESERVED_LOCK ){ + rc = 1; + OSTRACE3("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; + OSTRACE3("TEST WR-LOCK %d %d (remote)\n", pFile->h, rc); + } + return rc; +} + +/* +** 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(OsFile *id, int locktype){ + int type; + int rc = SQLITE_OK; + winFile *pFile = (winFile*)id; + assert( pFile!=0 ); + assert( locktype<=SHARED_LOCK ); + OSTRACE5("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 = SQLITE_IOERR_UNLOCK; + } + } + 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 = locktype; + return rc; +} + +/* +** Turn a relative pathname into a full pathname. Return a pointer +** to the full pathname stored in space obtained from sqliteMalloc(). +** The calling function is responsible for freeing this space once it +** is no longer needed. +*/ +char *sqlite3WinFullPathname(const char *zRelative){ + char *zFull; +#if defined(__CYGWIN__) + int nByte; + nByte = strlen(zRelative) + MAX_PATH + 1001; + zFull = sqliteMalloc( nByte ); + if( zFull==0 ) return 0; + if( cygwin_conv_to_full_win32_path(zRelative, zFull) ) return 0; +#elif OS_WINCE + /* WinCE has no concept of a relative pathname, or so I am told. */ + zFull = sqliteStrDup(zRelative); +#else + int nByte; + void *zConverted; + zConverted = convertUtf8Filename(zRelative); + if( isNT() ){ + WCHAR *zTemp; + nByte = GetFullPathNameW((WCHAR*)zConverted, 0, 0, 0) + 3; + zTemp = sqliteMalloc( nByte*sizeof(zTemp[0]) ); + if( zTemp==0 ){ + sqliteFree(zConverted); + return 0; + } + GetFullPathNameW((WCHAR*)zConverted, nByte, zTemp, 0); + sqliteFree(zConverted); + zFull = unicodeToUtf8(zTemp); + sqliteFree(zTemp); + }else{ + char *zTemp; + nByte = GetFullPathNameA((char*)zConverted, 0, 0, 0) + 3; + zTemp = sqliteMalloc( nByte*sizeof(zTemp[0]) ); + if( zTemp==0 ){ + sqliteFree(zConverted); + return 0; + } + GetFullPathNameA((char*)zConverted, nByte, zTemp, 0); + sqliteFree(zConverted); + zFull = mbcsToUtf8(zTemp); + sqliteFree(zTemp); + } +#endif + return zFull; +} + +/* +** The fullSync option is meaningless on windows. This is a no-op. +*/ +static void winSetFullSync(OsFile *id, int v){ + return; +} + +/* +** Return the underlying file handle for an OsFile +*/ +static int winFileHandle(OsFile *id){ + return (int)((winFile*)id)->h; +} + +/* +** Return an integer that indices the type of lock currently held +** by this handle. (Used for testing and analysis only.) +*/ +static int winLockState(OsFile *id){ + return ((winFile*)id)->locktype; +} + +/* +** 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 it's journal file) that the sector size will be the +** same for both. +*/ +static int winSectorSize(OsFile *id){ + return SQLITE_DEFAULT_SECTOR_SIZE; +} + +/* +** This vector defines all the methods that can operate on an OsFile +** for win32. +*/ +static const IoMethod sqlite3WinIoMethod = { + winClose, + winOpenDirectory, + winRead, + winWrite, + winSeek, + winTruncate, + winSync, + winSetFullSync, + winFileHandle, + winFileSize, + winLock, + winUnlock, + winLockState, + winCheckReservedLock, + winSectorSize, +}; + +/* +** Allocate memory for an OsFile. Initialize the new OsFile +** to the value given in pInit and return a pointer to the new +** OsFile. If we run out of memory, close the file and return NULL. +*/ +static int allocateWinFile(winFile *pInit, OsFile **pId){ + winFile *pNew; + pNew = sqliteMalloc( sizeof(*pNew) ); + if( pNew==0 ){ + CloseHandle(pInit->h); +#if OS_WINCE + sqliteFree(pInit->zDeleteOnClose); +#endif + *pId = 0; + return SQLITE_NOMEM; + }else{ + *pNew = *pInit; + pNew->pMethod = &sqlite3WinIoMethod; + pNew->locktype = NO_LOCK; + pNew->sharedLockByte = 0; + *pId = (OsFile*)pNew; + OpenCounter(+1); + return SQLITE_OK; + } +} + + +#endif /* SQLITE_OMIT_DISKIO */ +/*************************************************************************** +** Everything above deals with file I/O. Everything that follows deals +** with other miscellanous aspects of the operating system interface +****************************************************************************/ + +#if !defined(SQLITE_OMIT_LOAD_EXTENSION) +/* +** Interfaces for opening a shared library, finding entry points +** within the shared library, and closing the shared library. +*/ +void *sqlite3WinDlopen(const char *zFilename){ + HANDLE h; + void *zConverted = convertUtf8Filename(zFilename); + if( zConverted==0 ){ + return 0; + } + if( isNT() ){ + h = LoadLibraryW((WCHAR*)zConverted); + }else{ +#if OS_WINCE + return 0; +#else + h = LoadLibraryA((char*)zConverted); +#endif + } + sqliteFree(zConverted); + return (void*)h; + +} +void *sqlite3WinDlsym(void *pHandle, const char *zSymbol){ +#if OS_WINCE + /* The GetProcAddressA() routine is only available on wince. */ + return GetProcAddressA((HANDLE)pHandle, zSymbol); +#else + /* All other windows platforms expect GetProcAddress() to take + ** an Ansi string regardless of the _UNICODE setting */ + return GetProcAddress((HANDLE)pHandle, zSymbol); +#endif +} +int sqlite3WinDlclose(void *pHandle){ + return FreeLibrary((HANDLE)pHandle); +} +#endif /* !SQLITE_OMIT_LOAD_EXTENSION */ + +/* +** Get information to seed the random number generator. The seed +** is written into the buffer zBuf[256]. The calling function must +** supply a sufficiently large buffer. +*/ +int sqlite3WinRandomSeed(char *zBuf){ + /* We have to initialize zBuf to prevent valgrind from reporting + ** errors. The reports issued by valgrind are incorrect - we would + ** prefer that the randomness be increased by making use of the + ** uninitialized space in zBuf - but valgrind errors tend to worry + ** some users. Rather than argue, it seems easier just to initialize + ** the whole array and silence valgrind, even if that means less randomness + ** in the random seed. + ** + ** When testing, initializing zBuf[] to zero is all we do. That means + ** that we always use the same random number sequence.* This makes the + ** tests repeatable. + */ + memset(zBuf, 0, 256); + GetSystemTime((LPSYSTEMTIME)zBuf); + return SQLITE_OK; +} + +/* +** Sleep for a little while. Return the amount of time slept. +*/ +int sqlite3WinSleep(int ms){ + Sleep(ms); + return ms; +} + +/* +** Static variables used for thread synchronization +*/ +static int inMutex = 0; +#ifdef SQLITE_W32_THREADS + static DWORD mutexOwner; + static CRITICAL_SECTION cs; +#endif + +/* +** The following pair of routines implement mutual exclusion for +** multi-threaded processes. Only a single thread is allowed to +** executed code that is surrounded by EnterMutex() and LeaveMutex(). +** +** SQLite uses only a single Mutex. There is not much critical +** code and what little there is executes quickly and without blocking. +** +** Version 3.3.1 and earlier used a simple mutex. Beginning with +** version 3.3.2, a recursive mutex is required. +*/ +void sqlite3WinEnterMutex(){ +#ifdef SQLITE_W32_THREADS + static int isInit = 0; + while( !isInit ){ + static long lock = 0; + if( InterlockedIncrement(&lock)==1 ){ + InitializeCriticalSection(&cs); + isInit = 1; + }else{ + Sleep(1); + } + } + EnterCriticalSection(&cs); + mutexOwner = GetCurrentThreadId(); +#endif + inMutex++; +} +void sqlite3WinLeaveMutex(){ + assert( inMutex ); + inMutex--; +#ifdef SQLITE_W32_THREADS + assert( mutexOwner==GetCurrentThreadId() ); + LeaveCriticalSection(&cs); +#endif +} + +/* +** Return TRUE if the mutex is currently held. +** +** If the thisThreadOnly parameter is true, return true if and only if the +** calling thread holds the mutex. If the parameter is false, return +** true if any thread holds the mutex. +*/ +int sqlite3WinInMutex(int thisThreadOnly){ +#ifdef SQLITE_W32_THREADS + return inMutex>0 && (thisThreadOnly==0 || mutexOwner==GetCurrentThreadId()); +#else + return inMutex>0; +#endif +} + + +/* +** The following variable, if set to a non-zero value, becomes the result +** returned from sqlite3OsCurrentTime(). This is used for testing. +*/ +#ifdef SQLITE_TEST +int sqlite3_current_time = 0; +#endif + +/* +** 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 sqlite3WinCurrentTime(double *prNow){ + FILETIME ft; + /* FILETIME structure is a 64-bit value representing the number of + 100-nanosecond intervals since January 1, 1601 (= JD 2305813.5). + */ + double now; +#if OS_WINCE + SYSTEMTIME time; + GetSystemTime(&time); + SystemTimeToFileTime(&time,&ft); +#else + GetSystemTimeAsFileTime( &ft ); +#endif + now = ((double)ft.dwHighDateTime) * 4294967296.0; + *prNow = (now + ft.dwLowDateTime)/864000000000.0 + 2305813.5; +#ifdef SQLITE_TEST + if( sqlite3_current_time ){ + *prNow = sqlite3_current_time/86400.0 + 2440587.5; + } +#endif + return 0; +} + +/* +** Remember the number of thread-specific-data blocks allocated. +** Use this to verify that we are not leaking thread-specific-data. +** Ticket #1601 +*/ +#ifdef SQLITE_TEST +int sqlite3_tsd_count = 0; +# define TSD_COUNTER_INCR InterlockedIncrement(&sqlite3_tsd_count) +# define TSD_COUNTER_DECR InterlockedDecrement(&sqlite3_tsd_count) +#else +# define TSD_COUNTER_INCR /* no-op */ +# define TSD_COUNTER_DECR /* no-op */ +#endif + + + +/* +** If called with allocateFlag>1, then return a pointer to thread +** specific data for the current thread. Allocate and zero the +** thread-specific data if it does not already exist necessary. +** +** If called with allocateFlag==0, then check the current thread +** specific data. Return it if it exists. If it does not exist, +** then return NULL. +** +** If called with allocateFlag<0, check to see if the thread specific +** data is allocated and is all zero. If it is then deallocate it. +** Return a pointer to the thread specific data or NULL if it is +** unallocated or gets deallocated. +*/ +ThreadData *sqlite3WinThreadSpecificData(int allocateFlag){ + static int key; + static int keyInit = 0; + static const ThreadData zeroData = {0}; + ThreadData *pTsd; + + if( !keyInit ){ + sqlite3OsEnterMutex(); + if( !keyInit ){ + key = TlsAlloc(); + if( key==0xffffffff ){ + sqlite3OsLeaveMutex(); + return 0; + } + keyInit = 1; + } + sqlite3OsLeaveMutex(); + } + pTsd = TlsGetValue(key); + if( allocateFlag>0 ){ + if( !pTsd ){ + pTsd = sqlite3OsMalloc( sizeof(zeroData) ); + if( pTsd ){ + *pTsd = zeroData; + TlsSetValue(key, pTsd); + TSD_COUNTER_INCR; + } + } + }else if( pTsd!=0 && allocateFlag<0 + && memcmp(pTsd, &zeroData, sizeof(ThreadData))==0 ){ + sqlite3OsFree(pTsd); + TlsSetValue(key, 0); + TSD_COUNTER_DECR; + pTsd = 0; + } + return pTsd; +} +#endif /* OS_WIN */ |