VC知识库BLOG-wetwoo的小窝-For an example, see Obtaining a File Name From a File Handle

#include 
#include 
#include 
#include 
#include 
#include 

#define BUFSIZE 512

BOOL GetFileNameFromHandle(HANDLE hFile) 
{
  BOOL bSuccess = FALSE;
  TCHAR pszFilename[MAX_PATH+1];
  HANDLE hFileMap;

  // Get the file size.
  DWORD dwFileSizeHi = 0;
  DWORD dwFileSizeLo = GetFileSize(hFile, &dwFileSizeHi); 

  if( dwFileSizeLo == 0 && dwFileSizeHi == 0 )
  {
     printf("Cannot map a file with a length of zero.\n");
     return FALSE;
  }

  // Create a file mapping object.
  hFileMap = CreateFileMapping(hFile, 
                    NULL, 
                    PAGE_READONLY,
                    0, 
                    MAX_PATH,
                    NULL);

  if (hFileMap) 
  {
    // Create a file mapping to get the file name.
    void* pMem = MapViewOfFile(hFileMap, FILE_MAP_READ, 0, 0, 1);

    if (pMem) 
    {
      if (GetMappedFileName (GetCurrentProcess(), 
                             pMem, 
                             pszFilename,
                             MAX_PATH)) 
      {

        // Translate path with device name to drive letters.
        TCHAR szTemp[BUFSIZE];
        szTemp[0] = '\0';

        if (GetLogicalDriveStrings(BUFSIZE-1, szTemp)) 
        {
          TCHAR szName[MAX_PATH];
          TCHAR szDrive[3] = TEXT(" :");
          BOOL bFound = FALSE;
          TCHAR* p = szTemp;

          do 
          {
            // Copy the drive letter to the template string
            *szDrive = *p;

            // Look up each device name
            if (QueryDosDevice(szDrive, szName, BUFSIZE))
            {
              UINT uNameLen = _tcslen(szName);

              if (uNameLen < MAX_PATH) 
              {
                bFound = _tcsnicmp(pszFilename, szName, 
                    uNameLen) == 0;

                if (bFound) 
                {
                  // Reconstruct pszFilename using szTempFile
                  // Replace device path with DOS path
                  TCHAR szTempFile[MAX_PATH];
                  StringCchPrintf(szTempFile,
                            MAX_PATH,
                            TEXT("%s%s"),
                            szDrive,
                            pszFilename+uNameLen);
                  StringCchCopyN(pszFilename, MAX_PATH+1, szTempFile, _tcslen(szTempFile));
                }
              }
            }

            // Go to the next NULL character.
            while (*p++);
          } while (!bFound && *p); // end of string
        }
      }
      bSuccess = TRUE;
      UnmapViewOfFile(pMem);
    } 

    CloseHandle(hFileMap);
  }
  _tprintf(TEXT("File name is %s\n"), pszFilename);
  return(bSuccess);
}

posted on 2008-08-14 16:28 wetwoo的小窝 阅读(554)   

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