C++ MapViewOfFile fails

C++ MapViewOfFile fails

本文关键字:fails MapViewOfFile C++      更新时间:2023-10-16

我正在尝试使用VS2010在Windows上对文件进行内存映射。我在 DLL 中执行此操作。DLL 的第一个实例可以很好地映射文件。同一进程中的第二个实例导致

*ppvData = ::MapViewOfFile( *phMapping, FILE_MAP_READ, 0, 0, 0 );

失败并显示错误"此命令没有足够的内存可用"。我不确定为什么会发生这种情况。

如果我映射 2 个不同的文件而不是两次相同的文件,则一切正常,所以我不信任"内存不足"错误消息。

谢谢。

hr = MapFile(sPath, &m_hVoiceData, &m_pVoiceData,wsErr );
HRESULT CTTSEngObj::MapFile( wstring uPath,  // Value that contains file path
                            HANDLE * phMapping,          // Pointer to file mapping handle
                            void ** ppvData,             // Pointer to the data
                            wstring &uError)
{
    HRESULT hr = S_OK;
    CSpDynamicString dstrFilePath(uPath.c_str());
    if ( SUCCEEDED( hr ) )
    {
        bool fWorked = false;
        *phMapping = NULL;
        *ppvData = NULL;
        HANDLE hFile;
#ifdef _WIN32_WCE
        hFile = CreateFileForMapping( dstrFilePath, GENERIC_READ,
                                      FILE_SHARE_READ, NULL, OPEN_EXISTING,
                                      FILE_ATTRIBUTE_NORMAL, NULL );
#else
        hFile = CreateFile(CW2T(dstrFilePath), GENERIC_READ,
                            FILE_SHARE_READ, NULL, OPEN_EXISTING,
                            FILE_ATTRIBUTE_NORMAL, NULL );
#endif
        if (hFile != INVALID_HANDLE_VALUE)
        {
            *phMapping = ::CreateFileMapping( hFile, NULL, PAGE_READONLY, 0, 0, NULL );
            if (*phMapping)
            {
                *ppvData = ::MapViewOfFile( *phMapping, FILE_MAP_READ, 0, 0, 0 );
                if (*ppvData)
                {
                    fWorked = true;
                }
                else
                {
                    uError=GetLastErrorStdStrW();
                }
            }
            else
            {
                uError=L"mapfile: fm failed";
            }
            ::CloseHandle( hFile );
        }
        else
        {
            uError=L"mapfile: invalidhandle";
        }
        if (!fWorked)
        {
            hr = HRESULT_FROM_WIN32(::GetLastError());
            if (*phMapping)
            {
                ::CloseHandle(*phMapping);
                *phMapping = NULL;
            }
        }
    }
    else
    {
        uError=L"mapfile: dynstr";
    }
    return hr;
} /* CTTSEngObj::MapFile */

它是这样宣布的:

class ATL_NO_VTABLE CTTSEngObj : 
    public CComObjectRootEx<CComMultiThreadModel>,
    public CComCoClass<CTTSEngObj, &CLSID_SampleTTSEngine>,
    public ISpTTSEngine,
    public ISpObjectWithToken
{
  private:
    CComPtr<ISpObjectToken> m_cpToken;
    HANDLE                  m_hVoiceData;
    void*                   m_pVoiceData;

您请求将整个文件映射到内存中。它有多大?未分配进程的地址空间很可能没有足够大的连续范围。