dibfile.c

《Windows程序设计》配套代码、LZW压缩算法源代码、Socket异步通信示程序代码

/*---------------------------------
   DIBFILE.C -- DIB File Functions
  ---------------------------------*/

#include <windows.h>
#include <commdlg.h>
#include "dibfile.h"

static OPENFILENAME ofn ;

void DibFileInitialize (HWND hwnd)
{
     static TCHAR szFilter[] = TEXT ("Bitmap Files (*.BMP)\0*.bmp\0")  \
                               TEXT ("All Files (*.*)\0*.*\0\0") ;
     
     ofn.lStructSize       = sizeof (OPENFILENAME) ;
     ofn.hwndOwner         = hwnd ;
     ofn.hInstance         = NULL ;
     ofn.lpstrFilter       = szFilter ;
     ofn.lpstrCustomFilter = NULL ;
     ofn.nMaxCustFilter    = 0 ;
     ofn.nFilterIndex      = 0 ;
     ofn.lpstrFile         = NULL ;          // Set in Open and Close functions
     ofn.nMaxFile          = MAX_PATH ;
     ofn.lpstrFileTitle    = NULL ;          // Set in Open and Close functions
     ofn.nMaxFileTitle     = MAX_PATH ;
     ofn.lpstrInitialDir   = NULL ;
     ofn.lpstrTitle        = NULL ;
     ofn.Flags             = 0 ;             // Set in Open and Close functions
     ofn.nFileOffset       = 0 ;
     ofn.nFileExtension    = 0 ;
     ofn.lpstrDefExt       = TEXT ("bmp") ;
     ofn.lCustData         = 0 ;
     ofn.lpfnHook          = NULL ;
     ofn.lpTemplateName    = NULL ;
}

BOOL DibFileOpenDlg (HWND hwnd, PTSTR pstrFileName, PTSTR pstrTitleName)
{
     ofn.hwndOwner         = hwnd ;
     ofn.lpstrFile         = pstrFileName ;
     ofn.lpstrFileTitle    = pstrTitleName ;
     ofn.Flags             = 0 ;
     
     return GetOpenFileName (&ofn) ;
}

BOOL DibFileSaveDlg (HWND hwnd, PTSTR pstrFileName, PTSTR pstrTitleName)
{
     ofn.hwndOwner         = hwnd ;
     ofn.lpstrFile         = pstrFileName ;
     ofn.lpstrFileTitle    = pstrTitleName ;
     ofn.Flags             = OFN_OVERWRITEPROMPT ;
     
     return GetSaveFileName (&ofn) ;
}

BITMAPFILEHEADER * DibLoadImage (PTSTR pstrFileName)
{
     BOOL               bSuccess ;
     DWORD              dwFileSize, dwHighSize, dwBytesRead ;
     HANDLE             hFile ;
     BITMAPFILEHEADER * pbmfh ;

     hFile = CreateFile (pstrFileName, GENERIC_READ, FILE_SHARE_READ, NULL,
                         OPEN_EXISTING, FILE_FLAG_SEQUENTIAL_SCAN, NULL) ;

     if (hFile == INVALID_HANDLE_VALUE)
          return NULL ;

     dwFileSize = GetFileSize (hFile, &dwHighSize) ;

     if (dwHighSize)
     {
          CloseHandle (hFile) ;
          return NULL ;
     }

     pbmfh = malloc (dwFileSize) ;

     if (!pbmfh)
     {
          CloseHandle (hFile) ;
          return NULL ;
     }

     bSuccess = ReadFile (hFile, pbmfh, dwFileSize, &dwBytesRead, NULL) ;
     CloseHandle (hFile) ;

     if (!bSuccess || (dwBytesRead != dwFileSize)         
                   || (pbmfh->bfType != * (WORD *) "BM") 
                   || (pbmfh->bfSize != dwFileSize))
     {
          free (pbmfh) ;
          return NULL ;
     }
     return pbmfh ;
}

BOOL DibSaveImage (PTSTR pstrFileName, BITMAPFILEHEADER * pbmfh)
{
     BOOL   bSuccess ;
     DWORD  dwBytesWritten ;
     HANDLE hFile ;

     hFile = CreateFile (pstrFileName, GENERIC_WRITE, 0, NULL,
                         CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL) ;

     if (hFile == INVALID_HANDLE_VALUE)
          return FALSE ;

     bSuccess = WriteFile (hFile, pbmfh, pbmfh->bfSize, &dwBytesWritten, NULL) ;
     CloseHandle (hFile) ;

     if (!bSuccess || (dwBytesWritten != pbmfh->bfSize))
     {
          DeleteFile (pstrFileName) ;
          return FALSE ;
     }
     return TRUE ;
}