SQLite

******************************************************************************
**
** This file contains code that is specific to windows.
*/
#include "sqliteInt.h"
#if OS_WIN               /* This file is used for windows only */


/*
** A Note About Memory Allocation:
**
** This driver uses malloc()/free() directly rather than going through
** the SQLite-wrappers sqlite3_malloc()/sqlite3_free().  Those wrappers
** are designed for use on embedded systems where memory is scarce and
** malloc failures happen frequently.  Win32 does not typically run on
** embedded systems, and when it does the developers normally have bigger
** problems to worry about than running out of memory.  So there is not
** a compelling need to use the wrappers.
**
** But there is a good reason to not use the wrappers.  If we use the
** wrappers then we will get simulated malloc() failures within this
** driver.  And that causes all kinds of problems for our tests.  We
** could enhance SQLite to deal with simulated malloc failures within
** the OS driver, but the code to deal with those failure would not
** be exercised on Linux (which does not need to malloc() in the driver)
** and so we would have difficulty writing coverage tests for that
** code.  Better to leave the code out, we think.
**
** The point of this discussion is as follows:  When creating a new
** OS layer for an embedded system, if you use this file as an example,
** avoid the use of malloc()/free().  Those routines work ok on windows
** desktops but not so well in embedded systems.
*/

#include <winbase.h>

#ifdef __CYGWIN__
# include <sys/cygwin.h>
#endif

/*

    return sqlite3_os_type==2;
  }
#endif /* OS_WINCE */

/*
** Convert a UTF-8 string to microsoft unicode (UTF-16?). 
**
** Space to hold the returned string is obtained from malloc.
*/
static WCHAR *utf8ToUnicode(const char *zFilename){
  int nChar;
  WCHAR *zWideFilename;

  nChar = MultiByteToWideChar(CP_UTF8, 0, zFilename, -1, NULL, 0);
  zWideFilename = malloc( nChar*sizeof(zWideFilename[0]) );
  if( zWideFilename==0 ){
    return 0;
  }
  nChar = MultiByteToWideChar(CP_UTF8, 0, zFilename, -1, zWideFilename, nChar);
  if( nChar==0 ){
    free(zWideFilename);
    zWideFilename = 0;
  }
  return zWideFilename;
}

/*
** Convert microsoft unicode to UTF-8.  Space to hold the returned string is
** obtained from malloc().
*/
static char *unicodeToUtf8(const WCHAR *zWideFilename){
  int nByte;
  char *zFilename;

  nByte = WideCharToMultiByte(CP_UTF8, 0, zWideFilename, -1, 0, 0, 0, 0);
  zFilename = malloc( nByte );
  if( zFilename==0 ){
    return 0;
  }
  nByte = WideCharToMultiByte(CP_UTF8, 0, zWideFilename, -1, zFilename, nByte,
                              0, 0);
  if( nByte == 0 ){
    free(zFilename);
    zFilename = 0;
  }
  return zFilename;
}

/*
** Convert an ansi string to microsoft unicode, based on the
** current codepage settings for file apis.
** 
** Space to hold the returned string is obtained
** from malloc.
*/
static WCHAR *mbcsToUnicode(const char *zFilename){
  int nByte;
  WCHAR *zMbcsFilename;
  int codepage = AreFileApisANSI() ? CP_ACP : CP_OEMCP;

  nByte = MultiByteToWideChar(codepage, 0, zFilename, -1, NULL,0)*sizeof(WCHAR);
  zMbcsFilename = malloc( nByte*sizeof(zMbcsFilename[0]) );
  if( zMbcsFilename==0 ){
    return 0;
  }
  nByte = MultiByteToWideChar(codepage, 0, zFilename, -1, zMbcsFilename, nByte);
  if( nByte==0 ){
    free(zMbcsFilename);
    zMbcsFilename = 0;
  }
  return zMbcsFilename;
}

/*
** Convert microsoft unicode to multibyte character string, based on the
** user's Ansi codepage.
**
** Space to hold the returned string is obtained from
** malloc().
*/
static char *unicodeToMbcs(const WCHAR *zWideFilename){
  int nByte;
  char *zFilename;
  int codepage = AreFileApisANSI() ? CP_ACP : CP_OEMCP;

  nByte = WideCharToMultiByte(codepage, 0, zWideFilename, -1, 0, 0, 0, 0);
  zFilename = malloc( nByte );
  if( zFilename==0 ){
    return 0;
  }
  nByte = WideCharToMultiByte(codepage, 0, zWideFilename, -1, zFilename, nByte,
                              0, 0);
  if( nByte == 0 ){
    free(zFilename);
    zFilename = 0;
  }
  return zFilename;
}

/*
** Convert multibyte character string to UTF-8.  Space to hold the
** returned string is obtained from malloc().
*/
static char *mbcsToUtf8(const char *zFilename){
  char *zFilenameUtf8;
  WCHAR *zTmpWide;

  zTmpWide = mbcsToUnicode(zFilename);
  if( zTmpWide==0 ){
    return 0;
  }
  zFilenameUtf8 = unicodeToUtf8(zTmpWide);
  free(zTmpWide);
  return zFilenameUtf8;
}

/*
** Convert UTF-8 to multibyte character string.  Space to hold the 
** returned string is obtained from malloc().
*/
static char *utf8ToMbcs(const char *zFilename){
  char *zFilenameMbcs;
  WCHAR *zTmpWide;

  zTmpWide = utf8ToUnicode(zFilename);
  if( zTmpWide==0 ){
    return 0;
  }
  zFilenameMbcs = unicodeToMbcs(zTmpWide);
  free(zTmpWide);
  return zFilenameMbcs;
}

#if OS_WINCE
/*************************************************************************
** This section contains code for WinCE only.
*/

  for (;*zTok;zTok++){
    if (*zTok == '\\') *zTok = '_';
  }

  /* Create/open the named mutex */
  pFile->hMutex = CreateMutexW(NULL, FALSE, zName);
  if (!pFile->hMutex){
    free(zName);
    return FALSE;
  }

  /* Acquire the mutex before continuing */
  winceMutexAcquire(pFile->hMutex);
  
  /* Since the names of named mutexes, semaphores, file mappings etc are 

  /* Set a flag that indicates we're the first to create the memory so it 
  ** must be zero-initialized */
  if (GetLastError() == ERROR_ALREADY_EXISTS){
    bInit = FALSE;
  }

  free(zName);

  /* If we succeeded in making the shared memory handle, map it. */
  if (pFile->hShared){
    pFile->shared = (winceLock*)MapViewOfFile(pFile->hShared, 
             FILE_MAP_READ|FILE_MAP_WRITE, 0, 0, sizeof(winceLock));
    /* If mapping failed, close the shared memory handle and erase it */
    if (!pFile->shared){

    /* De-reference and close our copy of the shared memory handle */
    UnmapViewOfFile(pFile->shared);
    CloseHandle(pFile->hShared);

    if( pFile->zDeleteOnClose ){
      DeleteFileW(pFile->zDeleteOnClose);
      free(pFile->zDeleteOnClose);
      pFile->zDeleteOnClose = 0;
    }

    /* Done with the mutex */
    winceMutexRelease(pFile->hMutex);    
    CloseHandle(pFile->hMutex);
    pFile->hMutex = NULL;

**
** The next block of code implements the VFS methods.
****************************************************************************/

/*
** Convert a UTF-8 filename into whatever form the underlying
** operating system wants filenames in.  Space to hold the result
** is obtained from malloc and must be freed by the calling
** function.
*/
static void *convertUtf8Filename(const char *zFilename){
  void *zConverted = 0;
  if( isNT() ){
    zConverted = utf8ToUnicode(zFilename);
  }else{

       dwFlagsAndAttributes,
       NULL
    );
#endif
  }
  if( h==INVALID_HANDLE_VALUE ){
    if( flags & SQLITE_OPEN_READWRITE ){
      free(zConverted);
      return winOpen(0, zName, id, 
             ((flags|SQLITE_OPEN_READONLY)&~SQLITE_OPEN_READWRITE), pOutFlags);
    }else{
      return SQLITE_CANTOPEN;
    }
  }
  if( pOutFlags ){

  pFile->h = h;
#if OS_WINCE
  if( (flags & (SQLITE_OPEN_READWRITE|SQLITE_OPEN_MAIN_DB)) ==
               (SQLITE_OPEN_READWRITE|SQLITE_OPEN_MAIN_DB)
       && !winceCreateLock(zFilename, &f)
  ){
    CloseHandle(h);
    free(zConverted);
    return SQLITE_CANTOPEN;
  }
  if( dwFlagsAndAttributes & FILE_FLAG_DELETEONCLOSE ){
    pFile->zDeleteOnClose = zConverted;
  }else
#endif
  {
    free(zConverted);
  }
  return SQLITE_OK;
}

/*
** Delete the named file.
**

#else
    do{
      rc = DeleteFileA(zConverted);
    }while( rc==0 && GetFileAttributesA(zConverted)!=0xffffffff
            && cnt++ < MX_DELETION_ATTEMPTS && (Sleep(100), 1) );
#endif
  }
  free(zConverted);
  OSTRACE2("DELETE \"%s\"\n", zFilename);
  return rc!=0 ? SQLITE_OK : SQLITE_IOERR;
}

/*
** Check the existance and status of a file.
*/

  }else{
#if OS_WINCE
    return SQLITE_NOMEM;
#else
    attr = GetFileAttributesA((char*)zConverted);
#endif
  }
  free(zConverted);
  switch( flags ){
    case SQLITE_ACCESS_EXISTS:
      rc = attr!=0xffffffff;
      break;
    case SQLITE_ACCESS_READWRITE:
      rc = (attr & FILE_ATTRIBUTE_READONLY)==0;
      break;

    sqlite3_snprintf(MAX_PATH-30, zTempPath, "%s", sqlite3_temp_directory);
  }else if( isNT() ){
    char *zMulti;
    WCHAR zWidePath[MAX_PATH];
    GetTempPathW(MAX_PATH-30, zWidePath);
    zMulti = unicodeToUtf8(zWidePath);
    if( zMulti ){
      sqlite3_snprintf(MAX_PATH-30, zTempPath, "%s", zMulti);
      free(zMulti);
    }else{
      return SQLITE_NOMEM;
    }
  }else{
    char *zUtf8;
    char zMbcsPath[MAX_PATH];
    GetTempPathA(MAX_PATH-30, zMbcsPath);
    zUtf8 = mbcsToUtf8(zMbcsPath);
    if( zUtf8 ){
      sqlite3_snprintf(MAX_PATH-30, zTempPath, "%s", zUtf8);
      free(zUtf8);
    }else{
      return SQLITE_NOMEM;
    }
  }
  for(i=strlen(zTempPath); i>0 && zTempPath[i-1]=='\\'; i--){}
  zTempPath[i] = 0;
  for(;;){

  int nByte;
  void *zConverted;
  char *zOut;
  zConverted = convertUtf8Filename(zRelative);
  if( isNT() ){
    WCHAR *zTemp;
    nByte = GetFullPathNameW((WCHAR*)zConverted, 0, 0, 0) + 3;
    zTemp = malloc( nByte*sizeof(zTemp[0]) );
    if( zTemp==0 ){
      free(zConverted);
      return SQLITE_NOMEM;
    }
    GetFullPathNameW((WCHAR*)zConverted, nByte, zTemp, 0);
    free(zConverted);
    zOut = unicodeToUtf8(zTemp);
    free(zTemp);
  }else{
    char *zTemp;
    nByte = GetFullPathNameA((char*)zConverted, 0, 0, 0) + 3;
    zTemp = malloc( nByte*sizeof(zTemp[0]) );
    if( zTemp==0 ){
      free(zConverted);
      return SQLITE_NOMEM;
    }
    GetFullPathNameA((char*)zConverted, nByte, zTemp, 0);
    free(zConverted);
    zOut = mbcsToUtf8(zTemp);
    free(zTemp);
  }
  if( zOut ){
    sqlite3_snprintf(pVfs->mxPathname, zFull, "%s", zOut);
    free(zOut);
    return SQLITE_OK;
  }else{
    return SQLITE_NOMEM;
  }
#endif
}

  }else{
#if OS_WINCE
    return 0;
#else
    h = LoadLibraryA((char*)zConverted);
#endif
  }
  free(zConverted);
  return (void*)h;
}
static void winDlError(sqlite3_vfs *pVfs, int nBuf, char *zBufOut){
  FormatMessage(
    FORMAT_MESSAGE_FROM_SYSTEM,
    NULL,
    GetLastError(),