SQLite

  HANDLE hFile;                   /* Open file handle */
  HANDLE hShmFile;                /* File handle for *-shm file */

  HANDLE hMap;                    /* File handle for mapping */
  LPVOID pMap;                    /* Pointer to mapping of file fd */
  size_t nMap;                    /* Size of mapping at pMap in bytes */
  int nShm;                       /* Number of entries in ahShm[]/apShm[] */
  LPHANDLE ahShm;                 /* Array of handles for shared mappings */
  LPVOID *apShm;                  /* Array of 32K shared memory segments */
};

static char *win32ShmFile(Win32File *p){
  char *zShm;
  int nName = strlen(p->zName);
  zShm = (char *)lsmMallocZero(p->pEnv, nName+4+1);
  if( zShm ){

  return zText;
}

#if !defined(win32IsNotFound)
#define win32IsNotFound(a) (((a)==ERROR_FILE_NOT_FOUND)  || \
                            ((a)==ERROR_PATH_NOT_FOUND))
#endif

static int win32Open(
  lsm_env *pEnv,
  const char *zFile,
  int flags,
  LPHANDLE phFile
){
  int rc;
  LPWSTR zConverted;

  zConverted = win32Utf8ToUnicode(pEnv, zFile);
  if( zConverted==0 ){
    rc = LSM_NOMEM_BKPT;
  }else{
    int bReadonly = (flags & LSM_OPEN_READONLY);
    DWORD dwDesiredAccess;
    DWORD dwShareMode = FILE_SHARE_READ | FILE_SHARE_WRITE;
    DWORD dwCreationDisposition;
    DWORD dwFlagsAndAttributes = FILE_ATTRIBUTE_NORMAL;
    HANDLE hFile;
    int nRetry = 0;
    if( bReadonly ){
      dwDesiredAccess = GENERIC_READ;
      dwCreationDisposition = OPEN_EXISTING;
    }else{
      dwDesiredAccess = GENERIC_READ | GENERIC_WRITE;
      dwCreationDisposition = OPEN_ALWAYS;
    }
    while( (hFile = CreateFileW((LPCWSTR)zConverted,
                                dwDesiredAccess,
                                dwShareMode, NULL,
                                dwCreationDisposition,
                                dwFlagsAndAttributes,
                                NULL))==INVALID_HANDLE_VALUE &&
                                win32RetryIoerr(pEnv, &nRetry) ){
      /* Noop */
    }
    lsmFree(pEnv, zConverted);
    if( hFile!=INVALID_HANDLE_VALUE ){
      *phFile = hFile;
      rc = LSM_OK;
    }else{
      if( win32IsNotFound(GetLastError()) ){
        rc = lsmErrorBkpt(LSM_IOERR_NOENT);
      }else{
        rc = LSM_IOERR_BKPT;
      }
    }
  }
  return rc;
}

static int lsmWin32OsOpen(
  lsm_env *pEnv,
  const char *zFile,
  int flags,
  lsm_file **ppFile
){
  int rc = LSM_OK;
  Win32File *pWin32File;

  pWin32File = lsmMallocZero(pEnv, sizeof(Win32File));
  if( pWin32File==0 ){
    rc = LSM_NOMEM_BKPT;
  }else{






    HANDLE hFile;

    rc = win32Open(pEnv, zFile, flags, &hFile);






    if( rc==LSM_OK ){

















      pWin32File->pEnv = pEnv;
      pWin32File->zName = zFile;
      pWin32File->hFile = hFile;
    }else{
      lsmFree(pEnv, pWin32File);
      pWin32File = 0;






    }
  }
  *ppFile = (lsm_file *)pWin32File;
  return rc;
}

static int lsmWin32OsWrite(

    overlapped.OffsetHigh = (LONG)((iOff>>32) & 0x7fffffff);
    aRem += nWrite;
    nRem -= nWrite;
  }
  if( nRem!=0 ) return LSM_IOERR_BKPT;
  return LSM_OK;
}

static int win32Truncate(
  HANDLE hFile,
  lsm_i64 nSize
){
  LARGE_INTEGER offset;
  offset.QuadPart = nSize;
  if( !SetFilePointerEx(hFile, offset, 0, FILE_BEGIN) ){
    return LSM_IOERR_BKPT;
  }
  if (!SetEndOfFile(hFile) ){
    return LSM_IOERR_BKPT;
  }
  return LSM_OK;
}

static int lsmWin32OsTruncate(
  lsm_file *pFile, /* File to write to */
  lsm_i64 nSize    /* Size to truncate file to */
){
  Win32File *pWin32File = (Win32File *)pFile;






  return win32Truncate(pWin32File->hFile, nSize);



}

static int lsmWin32OsRead(
  lsm_file *pFile, /* File to read from */
  lsm_i64 iOff,    /* Offset to read from */
  void *pData,     /* Read data into this buffer */
  int nData        /* Bytes of data to read */

  nReq = sizeof(fileInfo.nFileIndexHigh);
  memcpy(pBuf, &fileInfo.nFileIndexHigh, nReq);
  pBuf2 += nReq;
  nReq = sizeof(fileInfo.nFileIndexLow);
  memcpy(pBuf2, &fileInfo.nFileIndexLow, nReq);
  return LSM_OK;
}

static int win32Delete(
  lsm_env *pEnv,
  const char *zFile
){
  int rc;
  LPWSTR zConverted;

  zConverted = win32Utf8ToUnicode(pEnv, zFile);
  if( zConverted==0 ){
    rc = LSM_NOMEM_BKPT;
  }else{
    int nRetry = 0;
    DWORD attr;
    DWORD lastErrno;

    do {
      attr = GetFileAttributesW(zConverted);
      if ( attr==INVALID_FILE_ATTRIBUTES ){
        rc = LSM_IOERR_BKPT;
        break;
      }
      if ( attr&FILE_ATTRIBUTE_DIRECTORY ){
        rc = LSM_IOERR_BKPT; /* Files only. */
        break;
      }
      if ( DeleteFileW(zConverted) ){
        rc = LSM_OK; /* Deleted OK. */
        break;
      }
      if ( !win32RetryIoerr(pEnv, &nRetry) ){
        rc = LSM_IOERR_BKPT; /* No more retries. */
        break;
      }
    }while( 1 );
  }
  lsmFree(pEnv, zConverted);
  return rc;
}

static int lsmWin32OsUnlink(lsm_env *pEnv, const char *zFile){
  return win32Delete(pEnv, zFile);
}

int lsmWin32OsLock(lsm_file *pFile, int iLock, int eType){
  Win32File *pWin32File = (Win32File *)pFile;
  OVERLAPPED ovlp;

  assert( LSM_LOCK_UNLOCK==0 );

    }
  }
  UnlockFileEx(pWin32File->hFile, 0, (DWORD)nLock, 0, &ovlp);
  return LSM_OK;
}

int lsmWin32OsShmMap(lsm_file *pFile, int iChunk, int sz, void **ppShm){
  int rc;
  Win32File *pWin32File = (Win32File *)pFile;

  *ppShm = NULL;
  assert( sz>=0 );
  assert( sz==LSM_SHM_CHUNK_SIZE );
  if( iChunk>=pWin32File->nShm ){
    int i;
    void **apNew;
    int nNew = iChunk+1;
    lsm_i64 nReq = nNew * sz;
    LARGE_INTEGER fileSize;

    /* If the shared-memory file has not been opened, open it now. */
    if( pWin32File->hShmFile==NULL ){
      char *zShm = win32ShmFile(pWin32File);
      if( !zShm ) return LSM_NOMEM_BKPT;
      rc = win32Open(pWin32File->pEnv, zShm, 0, &pWin32File->hShmFile);
      lsmFree(pWin32File->pEnv, zShm);
      if( rc!=LSM_OK ){
        return rc;
      }
    }

    /* If the shared-memory file is not large enough to contain the
    ** requested chunk, cause it to grow.  */
    memset(&fileSize, 0, sizeof(LARGE_INTEGER));
    if( !GetFileSizeEx(pWin32File->hShmFile, &fileSize) ){
      return LSM_IOERR_BKPT;
    }
    assert( fileSize.QuadPart>=0 );
    if( fileSize.QuadPart<nReq ){
      rc = win32Truncate(pWin32File->hShmFile, nReq);
      if( rc!=LSM_OK ){
        return rc;
      }
    }

    apNew = (void **)lsmRealloc(pWin32File->pEnv, pWin32File->apShm,
                                sizeof(LPVOID) * nNew);
    if( !apNew ) return LSM_NOMEM_BKPT;
    for(i=pWin32File->nShm; i<nNew; i++){
      apNew[i] = NULL;
    }
    pWin32File->apShm = apNew;
    pWin32File->nShm = nNew;
  }

  if( pWin32File->apShm[iChunk]==NULL ){
    HANDLE hMap;
    LPVOID pMap;
    hMap = CreateFileMappingW(pWin32File->hShmFile, NULL, PAGE_READWRITE, 0,
                              (DWORD)sz, NULL);
    if( hMap==NULL ){
      return LSM_IOERR_BKPT;
    }
    pWin32File->ahShm[iChunk] = hMap;
    pMap = MapViewOfFile(hMap, FILE_MAP_WRITE | FILE_MAP_READ, 0, 0,
                         (SIZE_T)sz);
    if( pMap==NULL ){
      return LSM_IOERR_BKPT;
    }
    pWin32File->apShm[iChunk] = pMap;
    pWin32File->nMap = (SIZE_T)sz;
  }
  *ppShm = pWin32File->apShm[iChunk];
  return LSM_OK;
}

void lsmWin32OsShmBarrier(void){
  MemoryBarrier();
}

int lsmWin32OsShmUnmap(lsm_file *pFile, int bDelete){
  Win32File *pWin32File = (Win32File *)pFile;

  if( pWin32File->hShmFile!=NULL ){
    int i;
    for(i=0; i<pWin32File->nShm; i++){
      if( pWin32File->apShm[i]!=NULL ){
        UnmapViewOfFile(pWin32File->apShm[i]);
        pWin32File->apShm[i] = NULL;
      }
      if( pWin32File->ahShm[i]!=NULL ){
        CloseHandle(pWin32File->ahShm[i]);
        pWin32File->ahShm[i] = NULL;
      }
    }
    CloseHandle(pWin32File->hShmFile);
    pWin32File->hShmFile = 0;
    if( bDelete ){
      char *zShm = win32ShmFile(pWin32File);
      if( zShm ){ win32Delete(pWin32File->pEnv, zShm); }
      lsmFree(pWin32File->pEnv, zShm);
    }
  }
  return LSM_OK;
}

#define MX_CLOSE_ATTEMPT 3
static int lsmWin32OsClose(lsm_file *pFile){
  int rc;
  int nRetry = 0;
  Win32File *pWin32File = (Win32File *)pFile;