wasCSharpSQLite – Rev 1
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#define SQLITE_OS_WIN
using System;
using System.Diagnostics;
using System.IO;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading;
using DWORD = System.UInt64;
using HANDLE = System.IntPtr;
using i64 = System.Int64;
using sqlite3_int64 = System.Int64;
using u32 = System.UInt32;
using u8 = System.Byte;
#if WINDOWS_PHONE || SQLITE_SILVERLIGHT
using System.IO.IsolatedStorage;
#endif
namespace Community.CsharpSqlite
{
public partial class Sqlite3
{
/*
** 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. This is
** meaningless for the supposedly platform-neutral .Net. This now contains
** experimental changes to allow Linux/Mac OS X use. The ultimate solution
** should be substantially cleaner than this version, however.
** Stewart Adcock <stewart.adcock@medit.fr>
**
*************************************************************************
** Included in SQLite3 port to C#-SQLite; 2008 Noah B Hart
** C#-SQLite is an independent reimplementation of the SQLite software library
**
** SQLITE_SOURCE_ID: 2011-06-23 19:49:22 4374b7e83ea0a3fbc3691f9c0c936272862f32f2
**
*************************************************************************
*/
//#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 sqlite3Malloc()/sqlite3DbFree(db,ref ). 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 <winbase.h>
#if __CYGWIN__
//# include <sys/cygwin.h>
#endif
/*
** Macros used to determine whether or not to use threads.
*/
#if 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.
*/
#if !INVALID_FILE_ATTRIBUTES
//# define INVALID_FILE_ATTRIBUTES ((DWORD)-1)
const int INVALID_FILE_ATTRIBUTES = -1;
#endif
/*
** Determine if we are dealing with WindowsCE - which has a much
** reduced API.
*/
#if SQLITE_OS_WINCE
//# define AreFileApisANSI() 1
//# define GetDiskFreeSpaceW() 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
private static LockingStrategy lockingStrategy = HelperMethods.IsRunningMediumTrust() ? new MediumTrustLockingStrategy() : new LockingStrategy();
/*
** The winFile structure is a subclass of sqlite3_file* specific to the win32
** portability layer.
*/
//typedef struct sqlite3_file sqlite3_file;
public partial class sqlite3_file
{
public sqlite3_vfs pVfs; /* The VFS used to open this file */
public FileStream fs; /* Filestream access to this file*/
// public HANDLE h; /* Handle for accessing the file */
public int locktype; /* Type of lock currently held on this file */
public int sharedLockByte; /* Randomly chosen byte used as a shared lock */
public DWORD lastErrno; /* The Windows errno from the last I/O error */
public DWORD sectorSize; /* Sector size of the device file is on */
#if !SQLITE_OMIT_WAL
public winShm pShm; /* Instance of shared memory on this file */
#else
public object pShm; /* DUMMY Instance of shared memory on this file */
#endif
public string zPath; /* Full pathname of this file */
public int szChunk; /* Chunk size configured by FCNTL_CHUNK_SIZE */
#if SQLITE_OS_WINCE
Wstring 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 sqlite3_file */
winceLock *shared; /* Global shared lock memory for the file */
#endif
public void Clear()
{
pMethods = null;
fs = null;
locktype = 0;
sharedLockByte = 0;
lastErrno = 0;
sectorSize = 0;
}
};
/*
** Forward prototypes.
*/
//static int getSectorSize(
// sqlite3_vfs *pVfs,
// string 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.
*/
#if 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 bool isNT()
{
//if (sqlite3_os_type == 0)
//{
// OSVERSIONINFO sInfo;
// sInfo.dwOSVersionInfoSize = sInfo.Length;
// GetVersionEx(&sInfo);
// sqlite3_os_type = sInfo.dwPlatformId == VER_PLATFORM_WIN32_NT ? 2 : 1;
//}
//return sqlite3_os_type == 2;
return Environment.OSVersion.Platform >= PlatformID.Win32NT;
}
#endif // * SQLITE_OS_WINCE */
/*
** Convert a UTF-8 string to microsoft unicode (UTF-16?).
**
** Space to hold the returned string is obtained from malloc.
*/
//static WCHAR *utf8ToUnicode(string zFilename){
// int nChar;
// Wstring 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 = "";
// }
// return zWideFilename;
//}
/*
** Convert microsoft unicode to UTF-8. Space to hold the returned string is
** obtained from malloc().
*/
//static char *unicodeToUtf8(const Wstring zWideFilename){
// int nByte;
// string 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 = "";
// }
// 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(string zFilename){
// int nByte;
// Wstring zMbcsFilename;
// int codepage = AreFileApisANSI() ? CP_ACP : CP_OEMCP;
// nByte = MultiByteToWideChar(codepage, 0, zFilename, -1, NULL,0)*WCHAR.Length;
// 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 = "";
// }
// 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 Wstring zWideFilename){
// int nByte;
// string 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 = "";
// }
// return zFilename;
//}
/*
** Convert multibyte character string to UTF-8. Space to hold the
** returned string is obtained from malloc().
*/
//static char *sqlite3_win32_mbcs_to_utf8(string zFilename){
// string zFilenameUtf8;
// Wstring 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(string zFilename){
// string zFilenameMbcs;
// Wstring 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, ref string 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;
//string zOut = "";
//if( isNT() ){
//Wstring zTempWide = NULL;
//dwLen = FormatMessageW(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
// NULL,
// error,
// 0,
// (LPWSTR) &zTempWide,
// 0,
// 0);
#if SQLITE_SILVERLIGHT
zBuf = "Unknown error";
#else
zBuf = Marshal.GetLastWin32Error().ToString();//new Win32Exception( Marshal.GetLastWin32Error() ).Message;
#endif
//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{
// string zTemp = null;
// dwLen = FormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
// null,
// error,
// 0,
// ref 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 winLogError( int a, string b, string c )
{
StackTrace st = new StackTrace( new StackFrame( true ) );
StackFrame sf = st.GetFrame( 0 );
return winLogErrorAtLine( a, b, c, sf.GetFileLineNumber() );
}
static int winLogErrorAtLine(
int errcode, /* SQLite error code */
string zFunc, /* Name of OS function that failed */
string zPath, /* File path associated with error */
int iLine /* Source line number where error occurred */
){
string zMsg = null; /* Human readable error text */
int i; /* Loop counter */
DWORD iErrno;// = GetLastError(); /* Error code */
#if SQLITE_SILVERLIGHT
iErrno = (int)ERROR_NOT_SUPPORTED;
#else
iErrno = (u32)Marshal.GetLastWin32Error();
#endif
//zMsg[0] = 0;
getLastErrorMsg( 500, ref zMsg );
Debug.Assert( errcode != SQLITE_OK );
zPath = zPath ?? string.Empty;
for ( i = 0; i < zMsg.Length && zMsg[i] != '\r' && zMsg[i] != '\n'; i++ )
{
}
zMsg = zMsg.Substring( 0, i );
sqlite3_log(errcode,
"os_win.c:%d: (%d) %s(%s) - %s",
iLine, iErrno, zFunc, zPath, zMsg
);
return errcode;
}
#if SQLITE_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;
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(string zFilename, sqlite3_file pFile){
Wstring zTok;
Wstring zName = utf8ToUnicode(zFilename);
BOOL bInit = TRUE;
/* Initialize the local lockdata */
ZeroMemory(pFile.local, pFile.local).Length;
/* 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 = (u32)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, winceLock.Length,
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, winceLock).Length;
/* If mapping failed, close the shared memory handle and erase it */
if (!pFile.shared){
pFile.lastErrno = (u32)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, winceLock).Length;
}
winceMutexRelease(pFile.hMutex);
return TRUE;
}
/*
** Destroy the part of sqlite3_file that deals with wince locks
*/
static void winceDestroyLock(sqlite3_file pFile){
if (pFile.hMutex){
/* Acquire the mutex */
winceMutexAcquire(pFile.hMutex);
/* The following blocks should probably Debug.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){
Debug.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){
Debug.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.
*/
#if !INVALID_SET_FILE_POINTER
//# define INVALID_SET_FILE_POINTER ((DWORD)-1)
const int INVALID_SET_FILE_POINTER = -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( sqlite3_file id, 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() */
sqlite3_file pFile = id;
//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(id, lowerBits, &upperBits, FILE_BEGIN);
//if( (dwRet==INVALID_SET_FILE_POINTER && GetLastError()!=NO_ERROR) ){
// pFile->lastErrno = GetLastError();
// winLogError(SQLITE_IOERR_SEEK, "seekWinFile", pFile->zPath);
try
{
id.fs.Seek( iOffset, SeekOrigin.Begin ); // SetFilePointer(pFile.fs.Name, lowerBits, upperBits, FILE_BEGIN);
}
catch ( Exception e )
{
#if SQLITE_SILVERLIGHT
pFile.lastErrno = 1;
#else
pFile.lastErrno = (u32)Marshal.GetLastWin32Error();
#endif
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.
*/
public static int MX_CLOSE_ATTEMPT = 3;
static int winClose( sqlite3_file id )
{
bool rc;
int cnt = 0;
sqlite3_file pFile = (sqlite3_file)id;
Debug.Assert( id != null );
Debug.Assert( pFile.pShm == null );
#if SQLITE_DEBUG
OSTRACE( "CLOSE %d (%s)\n", pFile.fs.GetHashCode(), pFile.fs.Name );
#endif
do
{
try
{
pFile.fs.Close();
}
catch (Exception ex)
{
Console.WriteLine ("Exception: " + ex.ToString());
}
rc = true;
// rc = CloseHandle(pFile.h);
/* SimulateIOError( rc=0; cnt=MX_CLOSE_ATTEMPT; ); */
// if (!rc && ++cnt < MX_CLOSE_ATTEMPT) Thread.Sleep(100); //, 1) );
} while ( !rc && ++cnt < MX_CLOSE_ATTEMPT ); //, 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
#if SQLITE_TEST
OSTRACE( "CLOSE %d %s\n", pFile.fs.GetHashCode(), rc ? "ok" : "failed" );
OpenCounter( -1 );
#endif
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 */
byte[] pBuf, /* Write content into this buffer */
int amt, /* Number of bytes to read */
sqlite3_int64 offset /* Begin reading at this offset */
)
{
long rc;
sqlite3_file pFile = id;
int nRead; /* Number of bytes actually read from file */
Debug.Assert( id != null );
#if SQLITE_TEST
if ( SimulateIOError() )
return SQLITE_IOERR_READ;
#endif
#if SQLITE_DEBUG
OSTRACE( "READ %d lock=%d\n", pFile.fs.GetHashCode(), pFile.locktype );
#endif
if ( !id.fs.CanRead )
return SQLITE_IOERR_READ;
if ( seekWinFile( pFile, offset ) != 0 )
{
return SQLITE_FULL;
}
try
{
nRead = id.fs.Read( pBuf, 0, amt ); // i if( null==ReadFile(pFile->h, pBuf, amt, &nRead, 0) ){
}
catch ( Exception e )
{
#if SQLITE_SILVERLIGHT
pFile.lastErrno = 1;
#else
pFile.lastErrno = (u32)Marshal.GetLastWin32Error();
#endif
return winLogError(SQLITE_IOERR_READ, "winRead", pFile.zPath);
}
if ( nRead < amt )
{
/* Unread parts of the buffer must be zero-filled */
Array.Clear( pBuf, (int)nRead, (int)( amt - nRead ) ); // 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 */
byte[] 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 */
sqlite3_file pFile = id; /* File handle */
Debug.Assert( amt > 0 );
Debug.Assert( pFile != null );
#if SQLITE_TEST
if ( SimulateIOError() )
return SQLITE_IOERR_WRITE;
if ( SimulateDiskfullError() )
return SQLITE_FULL;
#endif
#if SQLITE_DEBUG
OSTRACE( "WRITE %d lock=%d\n", id.fs.GetHashCode(), id.locktype );
#endif
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 && WriteFile(pFile->h, aRem, nRem, &nWrite, 0) && nWrite>0 ){
// aRem += nWrite;
// nRem -= nWrite;
// }
long wrote = id.fs.Position;
try
{
Debug.Assert( pBuf.Length >= amt );
id.fs.Write( pBuf, 0, amt );
id.fs.Flush(); // For Mono??
rc = 1;// Success
wrote = id.fs.Position - wrote;
}
catch ( IOException e )
{
return SQLITE_READONLY;
}
if ( rc == 0 || amt > (int)wrote )
{
#if SQLITE_SILVERLIGHT
id.lastErrno = 1;
#else
id.lastErrno = (u32)Marshal.GetLastWin32Error();
#endif
if (( id.lastErrno == ERROR_HANDLE_DISK_FULL )
|| ( id.lastErrno == ERROR_DISK_FULL ))
{
return SQLITE_FULL;
}
else
{
return winLogError(SQLITE_IOERR_WRITE, "winWrite", pFile.zPath);
}
}
return SQLITE_OK;
}
/*
** Truncate an open file to a specified size
*/
static int winTruncate( sqlite3_file id, sqlite3_int64 nByte )
{
sqlite3_file pFile = id; /* File handle object */
int rc = SQLITE_OK; /* Return code for this function */
Debug.Assert( pFile != null );
#if SQLITE_DEBUG
OSTRACE( "TRUNCATE %d %lld\n", id.fs.Name, nByte );
#endif
#if SQLITE_TEST
if ( SimulateIOError() )
return SQLITE_IOERR_TRUNCATE;
if ( SimulateIOError() )
return SQLITE_IOERR_TRUNCATE;
#endif
/* 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 != 0 )
{
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);
//}
try
{
id.fs.SetLength( nByte );
rc = SQLITE_OK;
}
catch ( IOException e )
{
#if SQLITE_SILVERLIGHT
id.lastErrno = 1;
#else
id.lastErrno = (u32)Marshal.GetLastWin32Error();
#endif
rc = winLogError(SQLITE_IOERR_TRUNCATE, "winTruncate2", pFile.zPath);
}
OSTRACE( "TRUNCATE %d %lld %s\n", id.fs.GetHashCode(), nByte, rc == SQLITE_OK ? "ok" : "failed" );
return rc;
}
#if 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.
*/
#if !TCLSH
static int sqlite3_sync_count = 0;
static int sqlite3_fullsync_count = 0;
#else
static tcl.lang.Var.SQLITE3_GETSET sqlite3_sync_count = new tcl.lang.Var.SQLITE3_GETSET( "sqlite3_sync_count" );
static tcl.lang.Var.SQLITE3_GETSET sqlite3_fullsync_count = new tcl.lang.Var.SQLITE3_GETSET( "sqlite_fullsync_count" );
#endif
#endif
/*
** Make sure all writes to a particular file are committed to disk.
*/
static int winSync( sqlite3_file id, int flags )
{
#if !(NDEBUG) || !(SQLITE_NO_SYNC) || (SQLITE_DEBUG)
sqlite3_file pFile = (sqlite3_file)id;
bool rc;
#else
UNUSED_PARAMETER(id);
#endif
Debug.Assert( pFile != null );
/* Check that one of SQLITE_SYNC_NORMAL or FULL was passed */
Debug.Assert( ( flags & 0x0F ) == SQLITE_SYNC_NORMAL
|| ( flags & 0x0F ) == SQLITE_SYNC_FULL
);
OSTRACE( "SYNC %d lock=%d\n", pFile.fs.GetHashCode(), 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.
*/
#if SQLITE_TEST
if ( SimulateDiskfullError() )
return SQLITE_FULL;
#endif
#if !SQLITE_TEST
UNUSED_PARAMETER(flags);
#else
if ( (flags&0x0F)==SQLITE_SYNC_FULL )
{
#if !TCLSH
sqlite3_fullsync_count++;
}
sqlite3_sync_count++;
#else
sqlite3_fullsync_count.iValue++;
}
sqlite3_sync_count.iValue++;
#endif
#endif
/* If we compiled with the SQLITE_NO_SYNC flag, then syncing is a
** no-op
*/
#if !SQLITE_NO_SYNC
pFile.fs.Flush();
//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
return SQLITE_OK;
}
/*
** Determine the current size of a file in bytes
*/
static int winFileSize( sqlite3_file id, ref long pSize )
{
//DWORD upperBits;
//DWORD lowerBits;
// sqlite3_file pFile = (sqlite3_file)id;
// DWORD error;
Debug.Assert( id != null );
#if SQLITE_TEST
if ( SimulateIOError() )
return SQLITE_IOERR_FSTAT;
#endif
//lowerBits = GetFileSize(pFile.fs.Name, 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;
//// This fails on Mac OS X:
////pSize = id.fs.CanRead ? id.fs.Length : 0;
////return SQLITE_OK;
FileInfo fi = new FileInfo(id.fs.Name);
pSize = fi.Length;
return SQLITE_OK;
}
/*
** Acquire a reader lock.
** Different API routines are called depending on whether or not this
** is Win95 or WinNT.
*/
static int getReadLock( sqlite3_file pFile )
{
int res = 0;
if ( isNT() )
{
res = lockingStrategy.SharedLockFile( pFile, SHARED_FIRST, SHARED_SIZE );
}
/* isNT() is 1 if SQLITE_OS_WINCE==1, so this else is never executed.
*/
#if !SQLITE_OS_WINCE
//else
//{
// int lk;
// sqlite3_randomness(lk.Length, lk);
// pFile.sharedLockByte = (u16)((lk & 0x7fffffff)%(SHARED_SIZE - 1));
// res = pFile.fs.Lock( SHARED_FIRST + pFile.sharedLockByte, 0, 1, 0);
#endif
//}
if ( res == 0 )
{
#if SQLITE_SILVERLIGHT
pFile.lastErrno = 1;
#else
pFile.lastErrno = (u32)Marshal.GetLastWin32Error();
#endif
}
/* No need to log a failure to lock */
return res;
}
/*
** Undo a readlock
*/
static int unlockReadLock( sqlite3_file pFile )
{
int res = 1;
if ( isNT() )
{
try
{
lockingStrategy.UnlockFile( pFile, SHARED_FIRST, SHARED_SIZE ); // res = UnlockFile(pFile.h, SHARED_FIRST, 0, SHARED_SIZE, 0);
}
catch ( Exception e )
{
res = 0;
}
}
/* isNT() is 1 if SQLITE_OS_WINCE==1, so this else is never executed.
*/
#if !SQLITE_OS_WINCE
else
{
Debugger.Break(); // res = UnlockFile(pFile.h, SHARED_FIRST + pFilE.sharedLockByte, 0, 1, 0);
}
#endif
if ( res == 0 )
{
#if SQLITE_SILVERLIGHT
pFile.lastErrno = 1;
#else
pFile.lastErrno = (u32)Marshal.GetLastWin32Error();
#endif
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 )
{
// SAA TODO: Uh Oh!
if (Environment.OSVersion.Platform == PlatformID.MacOSX || Environment.OSVersion.Platform == PlatformID.Unix) {
return 0;
}
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 */
bool gotPendingLock = false;/* True if we acquired a PENDING lock this time */
sqlite3_file pFile = (sqlite3_file)id;
DWORD error = NO_ERROR;
Debug.Assert( id != null );
#if SQLITE_DEBUG
OSTRACE( "LOCK %d %d was %d(%d)\n",
pFile.fs.GetHashCode(), locktype, pFile.locktype, pFile.sharedLockByte );
#endif
/* 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
*/
Debug.Assert( pFile.locktype != NO_LOCK || locktype == SHARED_LOCK );
Debug.Assert( locktype != PENDING_LOCK );
Debug.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;
res = 0;
while ( cnt-- > 0 && res == 0 )//(res = LockFile(pFile.fs.SafeFileHandle.DangerousGetHandle().ToInt32(), PENDING_BYTE, 0, 1, 0)) == 0)
{
try
{
lockingStrategy.LockFile( pFile, PENDING_BYTE, 1 );
res = 1;
}
catch ( Exception e )
{
/* Try 3 times to get the pending lock. The pending lock might be
** held by another reader process who will release it momentarily.
*/
#if SQLITE_DEBUG
OSTRACE( "could not get a PENDING lock. cnt=%d\n", cnt );
#endif
Thread.Sleep( 1 );
}
}
gotPendingLock = ( res != 0 );
if ( 0 == res )
{
#if SQLITE_SILVERLIGHT
error = 1;
#else
error = (u32)Marshal.GetLastWin32Error();
#endif
}
}
/* Acquire a shared lock
*/
if ( locktype == SHARED_LOCK && res != 0 )
{
Debug.Assert( pFile.locktype == NO_LOCK );
res = getReadLock( pFile );
if ( res != 0 )
{
newLocktype = SHARED_LOCK;
}
else
{
#if SQLITE_SILVERLIGHT
error = 1;
#else
error = (u32)Marshal.GetLastWin32Error();
#endif
}
}
/* Acquire a RESERVED lock
*/
if ( ( locktype == RESERVED_LOCK ) && res != 0 )
{
Debug.Assert( pFile.locktype == SHARED_LOCK );
try
{
lockingStrategy.LockFile( pFile, RESERVED_BYTE, 1 );//res = LockFile(pFile.fs.SafeFileHandle.DangerousGetHandle().ToInt32(), RESERVED_BYTE, 0, 1, 0);
newLocktype = RESERVED_LOCK;
res = 1;
}
catch ( Exception e )
{
res = 0;
#if SQLITE_SILVERLIGHT
error = 1;
#else
error = (u32)Marshal.GetLastWin32Error();
#endif
}
if ( res != 0 )
{
newLocktype = RESERVED_LOCK;
}
else
{
#if SQLITE_SILVERLIGHT
error = 1;
#else
error = (u32)Marshal.GetLastWin32Error();
#endif
}
}
/* Acquire a PENDING lock
*/
if ( locktype == EXCLUSIVE_LOCK && res != 0 )
{
newLocktype = PENDING_LOCK;
gotPendingLock = false;
}
/* Acquire an EXCLUSIVE lock
*/
if ( locktype == EXCLUSIVE_LOCK && res != 0 )
{
Debug.Assert( pFile.locktype >= SHARED_LOCK );
res = unlockReadLock( pFile );
#if SQLITE_DEBUG
OSTRACE( "unreadlock = %d\n", res );
#endif
//res = LockFile(pFile.fs.SafeFileHandle.DangerousGetHandle().ToInt32(), SHARED_FIRST, 0, SHARED_SIZE, 0);
try
{
lockingStrategy.LockFile( pFile, SHARED_FIRST, SHARED_SIZE );
newLocktype = EXCLUSIVE_LOCK;
res = 1;
}
catch ( Exception e )
{
res = 0;
}
if ( res != 0 )
{
newLocktype = EXCLUSIVE_LOCK;
}
else
{
#if SQLITE_SILVERLIGHT
error = 1;
#else
error = (u32)Marshal.GetLastWin32Error();
#endif
#if SQLITE_DEBUG
OSTRACE( "error-code = %d\n", error );
#endif
getReadLock( pFile );
}
}
/* If we are holding a PENDING lock that ought to be released, then
** release it now.
*/
if ( gotPendingLock && locktype == SHARED_LOCK )
{
lockingStrategy.UnlockFile( pFile, PENDING_BYTE, 1 );
}
/* Update the state of the lock has held in the file descriptor then
** return the appropriate result code.
*/
if ( res != 0 )
{
rc = SQLITE_OK;
}
else
{
#if SQLITE_DEBUG
OSTRACE( "LOCK FAILED %d trying for %d but got %d\n", pFile.fs.GetHashCode(),
locktype, newLocktype );
#endif
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, ref int pResOut )
{
// SAA TODO: Uh Oh!
if (Environment.OSVersion.Platform == PlatformID.MacOSX || Environment.OSVersion.Platform == PlatformID.Unix) {
return 0;
}
int rc;
sqlite3_file pFile = (sqlite3_file)id;
if ( SimulateIOError() )
return SQLITE_IOERR_CHECKRESERVEDLOCK;
Debug.Assert( id != null );
if ( pFile.locktype >= RESERVED_LOCK )
{
rc = 1;
#if SQLITE_DEBUG
OSTRACE( "TEST WR-LOCK %d %d (local)\n", pFile.fs.Name, rc );
#endif
}
else
{
try
{
lockingStrategy.LockFile( pFile, RESERVED_BYTE, 1 );
lockingStrategy.UnlockFile( pFile, RESERVED_BYTE, 1 );
rc = 1;
}
catch ( IOException e )
{
rc = 0;
}
rc = 1 - rc; // !rc
#if SQLITE_DEBUG
OSTRACE( "TEST WR-LOCK %d %d (remote)\n", pFile.fs.GetHashCode(), rc );
#endif
}
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 )
{
// SAA TODO: Uh Oh!
if (Environment.OSVersion.Platform == PlatformID.MacOSX || Environment.OSVersion.Platform == PlatformID.Unix) {
return 0;
}
int type;
sqlite3_file pFile = (sqlite3_file)id;
int rc = SQLITE_OK;
Debug.Assert( pFile != null );
Debug.Assert( locktype <= SHARED_LOCK );
#if SQLITE_DEBUG
OSTRACE( "UNLOCK %d to %d was %d(%d)\n", pFile.fs.GetHashCode(), locktype,
pFile.locktype, pFile.sharedLockByte );
#endif
type = pFile.locktype;
if ( type >= EXCLUSIVE_LOCK )
{
lockingStrategy.UnlockFile( pFile, SHARED_FIRST, SHARED_SIZE ); // UnlockFile(pFile.h, SHARED_FIRST, 0, SHARED_SIZE, 0);
if ( locktype == SHARED_LOCK && getReadLock( pFile ) == 0 )
{
/* 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 )
{
try
{
lockingStrategy.UnlockFile( pFile, RESERVED_BYTE, 1 );// UnlockFile(pFile.h, RESERVED_BYTE, 0, 1, 0);
}
catch ( Exception e )
{
}
}
if ( locktype == NO_LOCK && type >= SHARED_LOCK )
{
unlockReadLock( pFile );
}
if ( type >= PENDING_LOCK )
{
try
{
lockingStrategy.UnlockFile( pFile, PENDING_BYTE, 1 );// UnlockFile(pFile.h, PENDING_BYTE, 0, 1, 0);
}
catch ( Exception e )
{
}
}
pFile.locktype = (u8)locktype;
return rc;
}
/*
** Control and query of the open file handle.
*/
static int winFileControl( sqlite3_file id, int op, ref sqlite3_int64 pArg )
{
switch ( op )
{
case SQLITE_FCNTL_LOCKSTATE:
{
pArg = (int)( (sqlite3_file)id ).locktype;
return SQLITE_OK;
}
case SQLITE_LAST_ERRNO:
{
pArg = (int)( (sqlite3_file)id ).lastErrno;
return SQLITE_OK;
}
case SQLITE_FCNTL_CHUNK_SIZE:
{
( (sqlite3_file)id ).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_SYNC_OMITTED:
{
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 )
{
Debug.Assert( id != null );
return (int)( id.sectorSize );
}
/*
** Return a vector of device characteristics.
*/
static int winDeviceCharacteristics( sqlite3_file id )
{
UNUSED_PARAMETER( id );
return 0;
}
#if !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 Debug.Assert() that the global mutex
** is held when required. This function is only used as part of Debug.Assert()
** statements. e.g.
**
** winShmEnterMutex()
** Debug.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));
}
#if 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 */
string 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 */
#if 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 */
#if 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 */
Debug.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;
Debug.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; i<p->nRegion; 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 */
Debug.Assert( pDbFd->pShm==null ); /* 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;
#if 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();
Debug.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 */
Debug.Assert( ofst>=0 && ofst+n<=SQLITE_SHM_NLOCK );
Debug.Assert( n>=1 );
Debug.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) );
Debug.Assert( n==1 || (flags & SQLITE_SHM_EXCLUSIVE)!=0 );
mask = (u16)((1U<<(ofst+n)) - (1U<<ofst));
Debug.Assert( n>1 || mask==(1<<ofst) );
sqlite3_mutex_enter(pShmNode->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;
Debug.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 ){
Debug.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( null==p ){
rc = winOpenSharedMemory(pDbFd);
if( rc!=SQLITE_OK ) return rc;
p = pDbFd->pShm;
}
pShmNode = p->pShmNode;
sqlite3_mutex_enter(pShmNode->mutex);
Debug.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( sz<nByte ){
/* The requested memory region does not exist. If isWrite is set to
** zero, exit early. *pp will be set to NULL and SQLITE_OK returned.
**
** Alternatively, if isWrite is non-zero, use ftruncate() to allocate
** the requested memory region.
*/
if( null==isWrite ) goto shmpage_out;
rc = winTruncate((sqlite3_file )&pShmNode->hFile, 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( null==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( null==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
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 */
out object pp /* OUT: Mapped memory */
)
{
pp = null;
return 0;
}
//# define winShmLock 0
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 */
)
{
return 0;
}
//# define winShmBarrier 0
static void winShmBarrier(
sqlite3_file fd /* Database holding the shared memory */
)
{
}
//# define winShmUnmap 0
static int winShmUnmap(
sqlite3_file fd, /* Database holding shared memory */
int deleteFlag /* Delete after closing if true */
)
{
return 0;
}
#endif //* #if !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 sqlite3_io_methods winIoMethod = new sqlite3_io_methods(
2, /* iVersion */
(dxClose)winClose, /* xClose */
(dxRead)winRead, /* xRead */
(dxWrite)winWrite, /* xWrite */
(dxTruncate)winTruncate, /* xTruncate */
(dxSync)winSync, /* xSync */
(dxFileSize)winFileSize, /* xFileSize */
(dxLock)winLock, /* xLock */
(dxUnlock)winUnlock, /* xUnlock */
(dxCheckReservedLock)winCheckReservedLock, /* xCheckReservedLock */
(dxFileControl)winFileControl, /* xFileControl */
(dxSectorSize)winSectorSize, /* xSectorSize */
(dxDeviceCharacteristics)winDeviceCharacteristics, /* xDeviceCharacteristics */
(dxShmMap)winShmMap, /* xShmMap */
(dxShmLock)winShmLock, /* xShmLock */
(dxShmBarrier)winShmBarrier, /* xShmBarrier */
(dxShmUnmap)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 string convertUtf8Filename( string zFilename )
{
return zFilename;
// string zConverted = "";
//if (isNT())
//{
// zConverted = utf8ToUnicode(zFilename);
/* isNT() is 1 if SQLITE_OS_WINCE==1, so this else is never executed.
*/
#if !SQLITE_OS_WINCE
//}
//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, StringBuilder zBuf )
{
const string zChars = "abcdefghijklmnopqrstuvwxyz0123456789";
//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.
*/
#if SQLITE_TEST
if ( SimulateIOError() )
return SQLITE_IOERR;
#endif
//if( sqlite3_temp_directory ){
// sqlite3_snprintf(MAX_PATH-30, zTempPath, "%s", sqlite3_temp_directory);
//}else if( isNT() ){
// string 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
//}else{
// string 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;
//}
StringBuilder zRandom = new StringBuilder( 20 );
i64 iRandom = 0;
for ( int i = 0; i < 15; i++ )
{
sqlite3_randomness( 1, ref iRandom );
zRandom.Append( (char)zChars[(int)( iRandom % ( zChars.Length - 1 ) )] );
}
// zBuf[j] = 0;
#if SQLITE_WINRT
zBuf.Append( Path.Combine(ApplicationData.Current.LocalFolder.Path, SQLITE_TEMP_FILE_PREFIX + zRandom.ToString()) );
#elif SQLITE_SILVERLIGHT
zBuf.Append(Path.Combine(sqlite3_temp_directory, SQLITE_TEMP_FILE_PREFIX + zRandom.ToString()));
#else
zBuf.Append(Path.GetTempPath() + SQLITE_TEMP_FILE_PREFIX + zRandom.ToString());
#endif
//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;
#if SQLITE_DEBUG
OSTRACE( "TEMP FILENAME: %s\n", zBuf.ToString() );
#endif
return SQLITE_OK;
}
/*
** Open a file.
*/
static int winOpen (
sqlite3_vfs pVfs, /* Not used */
string zName, /* Name of the file (UTF-8) */
sqlite3_file pFile, /* Write the SQLite file handle here */
int flags, /* Open mode flags */
out int pOutFlags /* Status return flags */
)
{
//HANDLE h;
FileStream fs = null;
FileAccess dwDesiredAccess;
FileShare dwShareMode;
FileMode dwCreationDisposition;
#if !(SQLITE_SILVERLIGHT || WINDOWS_MOBILE)
FileOptions dwFlagsAndAttributes;
#endif
#if SQLITE_OS_WINCE
int isTemp = 0;
#endif
//winFile* pFile = (winFile)id;
string zConverted; /* Filename in OS encoding */
string zUtf8Name = zName; /* Filename in UTF-8 encoding */
pOutFlags = 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.
*/
StringBuilder zTmpname = new StringBuilder (MAX_PATH + 1); /* Buffer used to create temp filename */
int rc = SQLITE_OK; /* Function Return Code */
int eType = (int)(flags & 0xFFFFFF00); /* Type of file to open */
bool isExclusive = (flags & SQLITE_OPEN_EXCLUSIVE) != 0;
bool isDelete = (flags & SQLITE_OPEN_DELETEONCLOSE) != 0;
bool isCreate = (flags & SQLITE_OPEN_CREATE) != 0;
bool isReadonly = (flags & SQLITE_OPEN_READONLY) != 0;
bool isReadWrite = (flags & SQLITE_OPEN_READWRITE) != 0;
bool isOpenJournal = (isCreate && (
eType == SQLITE_OPEN_MASTER_JOURNAL
|| eType == SQLITE_OPEN_MAIN_JOURNAL
|| eType == SQLITE_OPEN_WAL
));
/* 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.
*/
Debug.Assert ((isReadonly == false || isReadWrite == false) && (isReadWrite || isReadonly));
Debug.Assert (isCreate == false || isReadWrite);
Debug.Assert (isExclusive == false || isCreate);
Debug.Assert (isDelete == false || isCreate);
/* The main DB, main journal, WAL file and master journal are never
** automatically deleted. Nor are they ever temporary files. */
//Debug.Assert( ( !isDelete && !string.IsNullOrEmpty(zName) ) || eType != SQLITE_OPEN_MAIN_DB );
Debug.Assert ((!isDelete && !string.IsNullOrEmpty(zName)) || eType != SQLITE_OPEN_MAIN_JOURNAL);
Debug.Assert ((!isDelete && !string.IsNullOrEmpty(zName)) || eType != SQLITE_OPEN_MASTER_JOURNAL);
Debug.Assert ((!isDelete && !string.IsNullOrEmpty(zName)) || eType != SQLITE_OPEN_WAL);
/* Assert that the upper layer has set one of the "file-type" flags. */
Debug.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
);
Debug.Assert (pFile != null);
UNUSED_PARAMETER (pVfs);
pFile.fs = null;//.h = INVALID_HANDLE_VALUE;
/* If the second argument to this function is NULL, generate a
** temporary file name to use
*/
if (string.IsNullOrEmpty(zUtf8Name)) {
Debug.Assert (isDelete && !isOpenJournal);
rc = getTempname (MAX_PATH + 1, zTmpname);
if (rc != SQLITE_OK) {
return rc;
}
zUtf8Name = zTmpname.ToString ();
}
// /* Convert the filename to the system encoding. */
zConverted = zUtf8Name;// convertUtf8Filename( zUtf8Name );
if (Environment.OSVersion.Platform != PlatformID.MacOSX && Environment.OSVersion.Platform != PlatformID.Unix) {
if (zConverted.StartsWith ("/") && !zConverted.StartsWith ("//"))
zConverted = zConverted.Substring (1);
}
//if ( string.IsNullOrEmpty( zConverted ) )
//{
// return SQLITE_NOMEM;
//}
if ( isReadWrite )
{
dwDesiredAccess = FileAccess.Read | FileAccess.Write; // GENERIC_READ | GENERIC_WRITE;
}
else
{
dwDesiredAccess = FileAccess.Read; // 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 = FileMode.CreateNew;// CREATE_NEW;
}
else if ( isCreate )
{
/* Open existing file, or create if it doesn't exist */
dwCreationDisposition = FileMode.OpenOrCreate;// OPEN_ALWAYS;
}
else
{
/* Opens a file, only if it exists. */
dwCreationDisposition = FileMode.Open;//OPEN_EXISTING;
}
dwShareMode = FileShare.Read | FileShare.Write;// FILE_SHARE_READ | FILE_SHARE_WRITE;
if ( isDelete )
{
#if SQLITE_OS_WINCE
dwFlagsAndAttributes = FILE_ATTRIBUTE_HIDDEN;
isTemp = 1;
#else
#if !(SQLITE_SILVERLIGHT || WINDOWS_MOBILE)
dwFlagsAndAttributes = FileOptions.DeleteOnClose; // FILE_ATTRIBUTE_TEMPORARY
//| FILE_ATTRIBUTE_HIDDEN
//| FILE_FLAG_DELETE_ON_CLOSE;
#endif
#endif
}
else
{
#if !(SQLITE_SILVERLIGHT || WINDOWS_MOBILE)
dwFlagsAndAttributes = FileOptions.None; // FILE_ATTRIBUTE_NORMAL;
#endif
}
/* Reports from the internet are that performance is always
** better if FILE_FLAG_RANDOM_ACCESS is used. Ticket #2699. */
#if SQLITE_OS_WINCE
dwFlagsAndAttributes |= FileOptions.RandomAccess; // FILE_FLAG_RANDOM_ACCESS;
#endif
if ( isNT() )
{
//h = CreateFileW((WCHAR)zConverted,
// dwDesiredAccess,
// dwShareMode,
// NULL,
// dwCreationDisposition,
// dwFlagsAndAttributes,
// NULL
//);
//
// retry opening the file a few times; this is because of a racing condition between a delete and open call to the FS
//
int retries = 3;
while ( ( fs == null ) && ( retries > 0 ) )
try
{
retries--;
#if WINDOWS_PHONE || SQLITE_SILVERLIGHT
fs = new IsolatedStorageFileStream(zConverted, dwCreationDisposition, dwDesiredAccess, dwShareMode, IsolatedStorageFile.GetUserStoreForApplication());
#elif !(SQLITE_SILVERLIGHT || WINDOWS_MOBILE)
fs = new FileStream( zConverted, dwCreationDisposition, dwDesiredAccess, dwShareMode, 4096, dwFlagsAndAttributes );
#else
fs = new FileStream( zConverted, dwCreationDisposition, dwDesiredAccess, dwShareMode, 4096);
#endif
#if SQLITE_DEBUG
OSTRACE( "OPEN %d (%s)\n", fs.GetHashCode(), fs.Name );
#endif
}
catch ( Exception e )
{
Thread.Sleep( 100 );
}
/* 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
}
else
{
Debugger.Break(); // Not NT
//h = CreateFileA((char)zConverted,
// dwDesiredAccess,
// dwShareMode,
// NULL,
// dwCreationDisposition,
// dwFlagsAndAttributes,
// NULL
//);
#endif
}
OSTRACE( "OPEN %d %s 0x%lx %s\n",
pFile.GetHashCode(), zName, dwDesiredAccess,
fs == null ? "failed" : "ok" );
if ( fs == null || !fs.CanRead ) //(h == INVALID_HANDLE_VALUE)
{
#if SQLITE_SILVERLIGHT
pFile.lastErrno = 1;
#else
// pFile.lastErrno = GetLastError();
pFile.lastErrno = (u32)Marshal.GetLastWin32Error();
#endif
winLogError(SQLITE_CANTOPEN, "winOpen", zUtf8Name);
// free(zConverted);
if ( isReadWrite )
{
return winOpen( pVfs, zName, pFile,
( ( flags | SQLITE_OPEN_READONLY ) & ~( SQLITE_OPEN_CREATE | SQLITE_OPEN_READWRITE ) ), out pOutFlags );
}
else
{
return SQLITE_CANTOPEN_BKPT();
}
}
//if ( pOutFlags )
//{
if ( isReadWrite )
{
pOutFlags = SQLITE_OPEN_READWRITE;
}
else
{
pOutFlags = SQLITE_OPEN_READONLY;
}
//}
pFile.Clear(); // memset(pFile, 0, sizeof(*pFile));
pFile.pMethods = winIoMethod;
pFile.fs = fs;
pFile.lastErrno = NO_ERROR;
pFile.pVfs = pVfs;
pFile.pShm = null;
pFile.zPath = zName;
pFile.sectorSize = (ulong)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);
}
#if SQLITE_TEST
OpenCounter( +1 );
#endif
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 MX_DELETION_ATTEMPTS = 5;
static int winDelete(
sqlite3_vfs pVfs, /* Not used on win32 */
string zFilename, /* Name of file to delete */
int syncDir /* Not used on win32 */
)
{
int cnt = 0;
int rc;
int error;
string zConverted;
UNUSED_PARAMETER( pVfs );
UNUSED_PARAMETER( syncDir );
#if SQLITE_TEST
if ( SimulateIOError() )
return SQLITE_IOERR_DELETE;
#endif
zConverted = convertUtf8Filename( zFilename );
//if ( zConverted == null || zConverted == "" )
//{
// return SQLITE_NOMEM;
//}
if ( isNT() )
{
do
// DeleteFileW(zConverted);
//}while( ( ((rc = GetFileAttributesW(zConverted)) != INVALID_FILE_ATTRIBUTES)
// || ((error = GetLastError()) == ERROR_ACCESS_DENIED))
// && (++cnt < MX_DELETION_ATTEMPTS)
// && (Sleep(100), 1) );
{
#if WINDOWS_PHONE
if ( !System.IO.IsolatedStorage.IsolatedStorageFile.GetUserStoreForApplication().FileExists( zFilename ) )
#elif SQLITE_SILVERLIGHT
if (!IsolatedStorageFile.GetUserStoreForApplication().FileExists(zFilename))
#else
if ( !File.Exists( zFilename ) )
#endif
{
rc = SQLITE_IOERR;
break;
}
try
{
#if WINDOWS_PHONE
System.IO.IsolatedStorage.IsolatedStorageFile.GetUserStoreForApplication().DeleteFile(zFilename);
#elif SQLITE_SILVERLIGHT
IsolatedStorageFile.GetUserStoreForApplication().DeleteFile(zFilename);
#else
File.Delete( zConverted );
#endif
rc = SQLITE_OK;
}
catch ( IOException e )
{
rc = SQLITE_IOERR;
Thread.Sleep( 100 );
}
} while ( rc != SQLITE_OK && ++cnt < MX_DELETION_ATTEMPTS );
/* 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
}
else
{
do
{
//DeleteFileA( zConverted );
//}while( ( ((rc = GetFileAttributesA(zConverted)) != INVALID_FILE_ATTRIBUTES)
// || ((error = GetLastError()) == ERROR_ACCESS_DENIED))
// && (cnt++ < MX_DELETION_ATTEMPTS)
// && (Sleep(100), 1) );
if ( !File.Exists( zFilename ) )
{
rc = SQLITE_IOERR;
break;
}
try
{
File.Delete( zConverted );
rc = SQLITE_OK;
}
catch ( IOException e )
{
rc = SQLITE_IOERR;
Thread.Sleep( 100 );
}
} while ( rc != SQLITE_OK && cnt++ < MX_DELETION_ATTEMPTS );
#endif
}
//free(zConverted);
#if SQLITE_DEBUG
OSTRACE( "DELETE \"%s\"\n", zFilename );
#endif
if ( rc == SQLITE_OK )
return rc;
#if SQLITE_SILVERLIGHT
error = (int)ERROR_NOT_SUPPORTED;
#else
error = Marshal.GetLastWin32Error();
#endif
return ( ( rc == INVALID_FILE_ATTRIBUTES )
&& ( error == ERROR_FILE_NOT_FOUND ) ) ? SQLITE_OK :
winLogError(SQLITE_IOERR_DELETE, "winDelete", zFilename);
}
/*
** Check the existence and status of a file.
*/
static int winAccess(
sqlite3_vfs pVfs, /* Not used on win32 */
string zFilename, /* Name of file to check */
int flags, /* Type of test to make on this file */
out int pResOut /* OUT: Result */
)
{
FileAttributes attr = 0; // DWORD attr;
int rc = 0;
// void *zConverted;
UNUSED_PARAMETER( pVfs );
#if SQLITE_TEST
if ( SimulateIOError() )
{
pResOut = -1;
return SQLITE_IOERR_ACCESS;
}
#endif
//zConverted = convertUtf8Filename(zFilename);
// if( zConverted==0 ){
// return SQLITE_NOMEM;
// }
//if ( isNT() )
//{
//
// Do a quick test to prevent the try/catch block
if ( flags == SQLITE_ACCESS_EXISTS )
{
#if WINDOWS_PHONE
pResOut = System.IO.IsolatedStorage.IsolatedStorageFile.GetUserStoreForApplication().FileExists(zFilename) ? 1 : 0;
#elif SQLITE_SILVERLIGHT
pResOut = IsolatedStorageFile.GetUserStoreForApplication().FileExists(zFilename) ? 1 : 0;
#else
pResOut = File.Exists( zFilename ) ? 1 : 0;
#endif
return SQLITE_OK;
}
//
try
{
//WIN32_FILE_ATTRIBUTE_DATA sAttrData;
//memset(&sAttrData, 0, sizeof(sAttrData));
//if( GetFileAttributesExW((WCHAR)zConverted,
// GetFileExInfoStandard,
// &sAttrData) ){
// /* 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{
// if( GetLastError()!=ERROR_FILE_NOT_FOUND ){
// winLogError(SQLITE_IOERR_ACCESS, "winAccess", zFilename);
// free(zConverted);
// return SQLITE_IOERR_ACCESS;
// }else{
// attr = INVALID_FILE_ATTRIBUTES;
// }
//}
#if WINDOWS_MOBILE
if (new DirectoryInfo(zFilename).Exists)
#elif SQLITE_WINRT
if (HelperMethods.DirectoryExists(zFilename))
#elif WINDOWS_PHONE || SQLITE_SILVERLIGHT
if (System.IO.IsolatedStorage.IsolatedStorageFile.GetUserStoreForApplication().DirectoryExists(zFilename))
#else
if (Directory.Exists( zFilename ))
#endif
{
try
{
var tempName = new StringBuilder();
getTempname(MAX_PATH + 1, tempName);
string name = Path.Combine(zFilename, Path.GetFileNameWithoutExtension(tempName.ToString()));
#if SQLITE_WINRT
Task<StorageFolder> fileTask = StorageFolder.GetFolderFromPathAsync(path).AsTask<StorageFolder>();
fileTask.Wait();
attr = fileTask.Attributes;
#elif WINDOWS_PHONE || SQLITE_SILVERLIGHT
var stream = IsolatedStorageFile.GetUserStoreForApplication().CreateFile(name);
stream.Close();
IsolatedStorageFile.GetUserStoreForApplication().DeleteFile(name);
#else
FileStream fs = File.Create( name );
fs.Close();
File.Delete( name );
#endif
attr = FileAttributes.Normal;
}
catch ( IOException e )
{
attr = FileAttributes.ReadOnly;
}
}
}
/* 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
//}
//else
//{
// attr = GetFileAttributesA( (char)zConverted );
#endif
//}
catch ( IOException e )
{
winLogError(SQLITE_IOERR_ACCESS, "winAccess", zFilename);
}
// free(zConverted);
switch ( flags )
{
case SQLITE_ACCESS_READ:
case SQLITE_ACCESS_EXISTS:
#if SQLITE_WINRT
rc = attr == FileAttributes.Normal ? 1 : 0;// != INVALID_FILE_ATTRIBUTES;
#else
rc = attr != 0 ? 1 : 0;// != INVALID_FILE_ATTRIBUTES;
#endif
break;
case SQLITE_ACCESS_READWRITE:
#if SQLITE_WINRT
rc = attr != FileAttributes.Normal ? 0 : (int)( attr & FileAttributes.ReadOnly ) != 0 ? 0 : 1; //FILE_ATTRIBUTE_READONLY ) == 0;
#else
rc = attr == 0 ? 0 : (int)( attr & FileAttributes.ReadOnly ) != 0 ? 0 : 1; //FILE_ATTRIBUTE_READONLY ) == 0;
#endif
break;
default:
Debug.Assert(false, "Invalid flags argument" );
rc = 0;
break;
}
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 */
string zRelative, /* Possibly relative input path */
int nFull, /* Size of output buffer in bytes */
StringBuilder zFull /* Output buffer */
)
{
#if __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 && !__CYGWIN__
int nByte;
//string zConverted;
string zOut = null;
/* If this path name begins with "/X:", where "X" is any alphabetic
** character, discard the initial "/" from the pathname.
*/
if( zRelative[0]=='/' && Char.IsLetter(zRelative[1]) && zRelative[2]==':' ){
zRelative = zRelative.Substring(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. This function could fail if, for example, the
** current working directory has been unlinked.
*/
#if SQLITE_TEST
if ( SimulateIOError() )
return SQLITE_ERROR;
#endif
UNUSED_PARAMETER( nFull );
//// //convertUtf8Filename(zRelative));
//// if ( isNT() )
//// {
//// //string zTemp;
//// //nByte = GetFullPathNameW( zConverted, 0, 0, 0) + 3;
//// //zTemp = malloc( nByte*sizeof(zTemp[0]) );
//// //if( zTemp==0 ){
//// // free(zConverted);
//// // return SQLITE_NOMEM;
//// //}
//// //zTemp = GetFullPathNameW(zConverted, nByte, zTemp, 0);
//// // will happen on exit; was free(zConverted);
//// try
//// {
////#if WINDOWS_PHONE || SQLITE_SILVERLIGHT
//// zOut = zRelative;
////#else
//// zOut = Path.GetFullPath( zRelative ); // was unicodeToUtf8(zTemp);
////#endif
//// }
//// catch ( Exception e )
//// {
//// zOut = zRelative;
//// }
//// // will happen on exit; was 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
//// }
//// else
//// {
//// Debugger.Break(); // -- Not Running under NT
//// //string zTemp;
//// //nByte = GetFullPathNameA(zConverted, 0, 0, 0) + 3;
//// //zTemp = malloc( nByte*sizeof(zTemp[0]) );
//// //if( zTemp==0 ){
//// // free(zConverted);
//// // return SQLITE_NOMEM;
//// //}
//// //GetFullPathNameA( zConverted, nByte, zTemp, 0);
//// // free(zConverted);
//// //zOut = sqlite3_win32_mbcs_to_utf8(zTemp);
//// // free(zTemp);
////#endif
//// }
zOut = Path.GetFullPath( zRelative );
if ( zOut != null )
{
// sqlite3_snprintf(pVfs.mxPathname, zFull, "%s", zOut);
if ( zFull.Length > pVfs.mxPathname )
zFull.Length = pVfs.mxPathname;
zFull.Append( zOut );
// will happen on exit; was 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,
string zRelative /* UTF-8 file name */
)
{
#if FALSE
int bytesPerSector = SQLITE_DEFAULT_SECTOR_SIZE;
/* GetDiskFreeSpace is not supported under WINCE */
#if SQLITE_OS_WINCE
UNUSED_PARAMETER(pVfs);
UNUSED_PARAMETER(zRelative);
#else
StringBuilder zFullpath = new StringBuilder( MAX_PATH + 1 );
int rc;
//bool dwRet = false;
//int dwDummy = 0;
/*
** 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 );
#if SQLITE_TEST
SimulateIOError( return SQLITE_ERROR )
#endif
if ( rc == SQLITE_OK )
{
StringBuilder zConverted = new StringBuilder( convertUtf8Filename( zFullpath.ToString() ) );
if ( zConverted.Length != 0 )
{
if ( isNT() )
{
/* trim path to just drive reference */
//for ( ; *p ; p++ )
//{
// if ( *p == '\\' )
// {
// *p = '\0';
// break;
// }
//}
int i;
for ( i = 0 ; i < zConverted.Length && i < MAX_PATH ; i++ )
{
if ( zConverted[i] == '\\' )
{
i++;
break;
}
}
zConverted.Length = i;
//dwRet = GetDiskFreeSpace( zConverted,
// ref dwDummy,
// ref bytesPerSector,
// ref dwDummy,
// ref 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,
// ref bytesPerSector,
// dwDummy,
// dwDummy );
}
//free(zConverted);
}
// if ( !dwRet )
// {
// bytesPerSector = SQLITE_DEFAULT_SECTOR_SIZE;
// }
//}
//#endif
bytesPerSector = GetbytesPerSector( zConverted );
}
#endif
return bytesPerSector == 0 ? SQLITE_DEFAULT_SECTOR_SIZE : bytesPerSector;
#endif
return SQLITE_DEFAULT_SECTOR_SIZE;
}
#if !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, string 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
// }else{
// h = LoadLibraryA((char)zConverted);
#endif
// }
// free(zConverted);
// return (void)h;
//}
//static void winDlError(sqlite3_vfs pVfs, int nBuf, string zBufOut){
// UNUSED_PARAMETER(pVfs);
// getLastErrorMsg(nBuf, zBufOut);
//}
// static object winDlSym(sqlite3_vfs pVfs, HANDLE pHandle, String zSymbol){
// UNUSED_PARAMETER(pVfs);
//#if SQLITE_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
// }
// static void winDlClose( sqlite3_vfs pVfs, HANDLE pHandle )
// {
// UNUSED_PARAMETER(pVfs);
// FreeLibrary((HANDLE)pHandle);
// }
//TODO -- Fix This
static HANDLE winDlOpen( sqlite3_vfs vfs, string zFilename )
{
return new HANDLE();
}
static int winDlError( sqlite3_vfs vfs, int nByte, string zErrMsg )
{
return 0;
}
static HANDLE winDlSym( sqlite3_vfs vfs, HANDLE data, string zSymbol )
{
return new HANDLE();
}
static int winDlClose( sqlite3_vfs vfs, HANDLE data )
{
return 0;
}
#else // * if SQLITE_OMIT_LOAD_EXTENSION is defined: */
static object winDlOpen(ref sqlite3_vfs vfs, string zFilename) { return null; }
static int winDlError(ref sqlite3_vfs vfs, int nByte, ref string zErrMsg) { return 0; }
static object winDlSym(ref sqlite3_vfs vfs, object data, string zSymbol) { return null; }
static int winDlClose(ref sqlite3_vfs vfs, object data) { return 0; }
#endif
/*
** Write up to nBuf bytes of randomness into zBuf.
*/
//[StructLayout( LayoutKind.Explicit, Size = 16, CharSet = CharSet.Ansi )]
//public class _SYSTEMTIME
//{
// [FieldOffset( 0 )]
// public u32 byte_0_3;
// [FieldOffset( 4 )]
// public u32 byte_4_7;
// [FieldOffset( 8 )]
// public u32 byte_8_11;
// [FieldOffset( 12 )]
// public u32 byte_12_15;
//}
//[DllImport( "Kernel32.dll" )]
//private static extern bool QueryPerformanceCounter( out long lpPerformanceCount );
static int winRandomness( sqlite3_vfs pVfs, int nBuf, byte[] zBuf )
{
int n = 0;
UNUSED_PARAMETER( pVfs );
#if (SQLITE_TEST)
n = nBuf;
Array.Clear( zBuf, 0, n );// memset( zBuf, 0, nBuf );
#else
byte[] sBuf = BitConverter.GetBytes(System.DateTime.Now.Ticks);
zBuf[0] = sBuf[0];
zBuf[1] = sBuf[1];
zBuf[2] = sBuf[2];
zBuf[3] = sBuf[3];
;// memcpy(&zBuf[n], x, sizeof(x))
n += 16;// sizeof(x);
if ( sizeof( DWORD ) <= nBuf - n )
{
//DWORD pid = GetCurrentProcessId();
u32 processId;
#if !SQLITE_SILVERLIGHT
processId = (u32)Process.GetCurrentProcess().Id;
#else
processId = 28376023;
#endif
put32bits( zBuf, n, processId);//(memcpy(&zBuf[n], pid, sizeof(pid));
n += 4;// sizeof(pid);
}
if ( sizeof( DWORD ) <= nBuf - n )
{
//DWORD cnt = GetTickCount();
System.DateTime dt = new System.DateTime();
put32bits( zBuf, n, (u32)dt.Ticks );// memcpy(&zBuf[n], cnt, sizeof(cnt));
n += 4;// cnt.Length;
}
if ( sizeof( long ) <= nBuf - n )
{
long i;
i = System.DateTime.UtcNow.Millisecond;// QueryPerformanceCounter(out i);
put32bits( zBuf, n, (u32)( i & 0xFFFFFFFF ) );//memcpy(&zBuf[n], i, sizeof(i));
put32bits( zBuf, n, (u32)( i >> 32 ) );
n += sizeof( long );
}
#endif
return n;
}
/*
** Sleep for a little while. Return the amount of time slept.
*/
static int winSleep( sqlite3_vfs pVfs, int microsec )
{
Thread.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.
*/
#if SQLITE_TEST
#if !TCLSH
static int sqlite3_current_time = 0;// /* Fake system time in seconds since 1970. */
#else
static tcl.lang.Var.SQLITE3_GETSET sqlite3_current_time = new tcl.lang.Var.SQLITE3_GETSET( "sqlite3_current_time" );
#endif
#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, ref sqlite3_int64 piNow )
{
/* FILETIME structure is a 64-bit value representing the number of
100-nanosecond intervals since January 1, 1601 (= JD 2305813.5).
*/
//var ft = new FILETIME();
const sqlite3_int64 winFiletimeEpoch = 23058135 * (sqlite3_int64)8640000;
#if SQLITE_TEST
const sqlite3_int64 unixEpoch = 24405875 * (sqlite3_int64)8640000;
#endif
///* 2^32 - to avoid use of LL and warnings in gcc */
//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( ref ft );
// ft = System.DateTime.UtcNow.ToFileTime();
//#endif
//sqlite3_int64 ft = System.DateTime.UtcNow.ToFileTime();
//piNow = winFiletimeEpoch + ft;
//((((sqlite3_int64)ft.dwHighDateTime)*max32BitValue) +
// (sqlite3_int64)ft.dwLowDateTime)/(sqlite3_int64)10000;
piNow = winFiletimeEpoch + System.DateTime.UtcNow.ToFileTimeUtc() / (sqlite3_int64)10000;
#if SQLITE_TEST
#if !TCLSH
if ( ( sqlite3_current_time) != 0 )
{
piNow = 1000 * (sqlite3_int64)sqlite3_current_time + unixEpoch;
}
#else
if ( ( sqlite3_current_time.iValue ) != 0 )
{
piNow = 1000 * (sqlite3_int64)sqlite3_current_time.iValue + unixEpoch;
}
#endif
#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.
*/
static int winCurrentTime( sqlite3_vfs pVfs, ref double prNow )
{
int rc;
sqlite3_int64 i = 0;
rc = winCurrentTimeInt64( pVfs, ref i );
if ( 0 == 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, string zBuf){
** Debug.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, ref string zBuf )
{
UNUSED_PARAMETER( pVfs );
return getLastErrorMsg( nBuf, ref zBuf );
}
static sqlite3_vfs winVfs = new sqlite3_vfs(
3, /* iVersion */
-1, //sqlite3_file.Length, /* szOsFile */
MAX_PATH, /* mxPathname */
null, /* pNext */
"win32", /* zName */
0, /* pAppData */
(dxOpen)winOpen, /* xOpen */
(dxDelete)winDelete, /* xDelete */
(dxAccess)winAccess, /* xAccess */
(dxFullPathname)winFullPathname,/* xFullPathname */
(dxDlOpen)winDlOpen, /* xDlOpen */
(dxDlError)winDlError, /* xDlError */
(dxDlSym)winDlSym, /* xDlSym */
(dxDlClose)winDlClose, /* xDlClose */
(dxRandomness)winRandomness, /* xRandomness */
(dxSleep)winSleep, /* xSleep */
(dxCurrentTime)winCurrentTime, /* xCurrentTime */
(dxGetLastError)winGetLastError,/* xGetLastError */
(dxCurrentTimeInt64)winCurrentTimeInt64, /* xCurrentTimeInt64 */
null, /* xSetSystemCall */
null, /* xGetSystemCall */
null /* xNextSystemCall */
);
/*
** Initialize and deinitialize the operating system interface.
*/
static int sqlite3_os_init()
{
#if !SQLITE_OMIT_WAL
/* get memory map allocation granularity */
memset(&winSysInfo, 0, sizeof(SYSTEM_INFO));
GetSystemInfo(&winSysInfo);
Debug.Assert(winSysInfo.dwAllocationGranularity > 0);
#endif
sqlite3_vfs_register( winVfs, 1 );
return SQLITE_OK;
}
static int sqlite3_os_end()
{
return SQLITE_OK;
}
#endif // * SQLITE_OS_WIN */
//
// Windows DLL definitions
//
const int NO_ERROR = 0;
/// <summary>
/// Basic locking strategy for Console/Winform applications
/// </summary>
private class LockingStrategy
{
////#if !(SQLITE_SILVERLIGHT || WINDOWS_MOBILE)
//// [DllImport( "kernel32.dll" )]
//// static extern bool LockFileEx( IntPtr hFile, uint dwFlags, uint dwReserved,
//// uint nNumberOfBytesToLockLow, uint nNumberOfBytesToLockHigh,
//// [In] ref System.Threading.NativeOverlapped lpOverlapped );
////
//// const int LOCKFILE_FAIL_IMMEDIATELY = 1;
////#endif
public virtual void LockFile( sqlite3_file pFile, long offset, long length )
{
#if !(SQLITE_SILVERLIGHT || WINDOWS_MOBILE)
pFile.fs.Lock( offset, length );
#endif
}
public virtual int SharedLockFile( sqlite3_file pFile, long offset, long length )
{
#if !(SQLITE_SILVERLIGHT || WINDOWS_MOBILE)
Debug.Assert( length == SHARED_SIZE );
Debug.Assert( offset == SHARED_FIRST );
try
{
pFile.fs.Lock( offset + pFile.sharedLockByte, 1 );
}
catch ( IOException )
{
return 0;
}
#endif
return 1;
////#if !(SQLITE_SILVERLIGHT || WINDOWS_MOBILE)
//// Debug.Assert( length == SHARED_SIZE );
//// Debug.Assert( offset == SHARED_FIRST );
//// NativeOverlapped ovlp = new NativeOverlapped();
//// ovlp.OffsetLow = (int)offset;
//// ovlp.OffsetHigh = 0;
//// ovlp.EventHandle = IntPtr.Zero;
////
//// return LockFileEx( pFile.fs.Handle, LOCKFILE_FAIL_IMMEDIATELY, 0, (uint)length, 0, ref ovlp ) ? 1 : 0;
////#else
//// return 1;
////#endif
}
public virtual void UnlockFile( sqlite3_file pFile, long offset, long length )
{
#if !(SQLITE_SILVERLIGHT || WINDOWS_MOBILE)
pFile.fs.Unlock( offset, length );
#endif
}
}
/// <summary>
/// Locking strategy for Medium Trust. It uses the same trick used in the native code for WIN_CE
/// which doesn't support LockFileEx as well.
/// </summary>
private class MediumTrustLockingStrategy : LockingStrategy
{
public override int SharedLockFile( sqlite3_file pFile, long offset, long length )
{
#if !(SQLITE_SILVERLIGHT || WINDOWS_MOBILE)
Debug.Assert( length == SHARED_SIZE );
Debug.Assert( offset == SHARED_FIRST );
try
{
pFile.fs.Lock( offset + pFile.sharedLockByte, 1 );
}
catch ( IOException )
{
return 0;
}
#endif
return 1;
}
}
}
internal static class HelperMethods
{
public static bool IsRunningMediumTrust()
{
// placeholder method
// this is where it needs to check if it's running in an ASP.Net MediumTrust or lower environment
// in order to pick the appropriate locking strategy.
// For the purpose of running this on Mac OS X, we *always* run in medium trust mode.
////#if SQLITE_SILVERLIGHT
return true;
////#else
//// return false;
////#endif
}
}
}