C++ PathString::FindBack方法代码示例

void Disassembler::StaticInitialize()
{
    LIMITED_METHOD_CONTRACT;

#if USE_COREDISTOOLS_DISASSEMBLER
    _ASSERTE(!IsAvailable());

    HMODULE libraryHandle = nullptr;
    PathString libPath;
    DWORD result = WszGetModuleFileName(nullptr, libPath);
    if (result == 0) {
#ifdef _DEBUG
        wprintf(
            W("GetModuleFileName failed, function 'DisasmInstruction': error %u\n"),
            GetLastError());
#endif // _DEBUG
        return;
    }

#if defined(FEATURE_PAL)
    WCHAR delim = W('/');
#else
    WCHAR delim = W('\\');
#endif
    LPCWSTR libFileName = MAKEDLLNAME(W("coredistools"));
    PathString::Iterator iter = libPath.End();
    if (libPath.FindBack(iter, delim)) {
        libPath.Truncate(++iter);
        libPath.Append(libFileName);
    }
    else {
        _ASSERTE(!"unreachable");
    }

    LPCWSTR libraryName = libPath.GetUnicode();
    libraryHandle = CLRLoadLibrary(libraryName);
    do
    {
        if (libraryHandle == nullptr)
        {
        #ifdef _DEBUG
            wprintf(W("LoadLibrary failed for '%s': error %u\n"), libraryName, GetLastError());
        #endif // _DEBUG
            break;
        }

        External_InitDisasm =
            reinterpret_cast<decltype(External_InitDisasm)>(GetProcAddress(libraryHandle, "InitDisasm"));
        if (External_InitDisasm == nullptr)
        {
        #ifdef _DEBUG
            wprintf(
                W("GetProcAddress failed for library '%s', function 'InitDisasm': error %u\n"),
                libraryName,
                GetLastError());
        #endif // _DEBUG
            break;
        }

        External_DisasmInstruction =
            reinterpret_cast<decltype(External_DisasmInstruction)>(GetProcAddress(libraryHandle, "DisasmInstruction"));
        if (External_DisasmInstruction == nullptr)
        {
        #ifdef _DEBUG
            wprintf(
                W("GetProcAddress failed for library '%s', function 'DisasmInstruction': error %u\n"),
                libraryName,
                GetLastError());
        #endif // _DEBUG
            break;
        }

        External_FinishDisasm =
            reinterpret_cast<decltype(External_FinishDisasm)>(GetProcAddress(libraryHandle, "FinishDisasm"));
        if (External_FinishDisasm == nullptr)
        {
        #ifdef _DEBUG
            wprintf(
                W("GetProcAddress failed for library '%s', function 'FinishDisasm': error %u\n"),
                libraryName,
                GetLastError());
        #endif // _DEBUG
            break;
        }

        // Set this last to indicate successful load of the library and all exports
        s_libraryHandle = libraryHandle;
        _ASSERTE(IsAvailable());
        return;
    } while (false);

    _ASSERTE(!IsAvailable());
    
#endif // USE_COREDISTOOLS_DISASSEMBLER
}

//*****************************************************************************
// This is used in conjunction with GetClassFromCORPath.  See it for details
// of the algorithm.
//*****************************************************************************
HRESULT CORPATHService::GetClassFromDir(
    __in __in_z LPWSTR        wzClassname,            // Fully qualified class name.
    __in SString&             directory,             // Directory to try. at most appended with a '\\'
    mdTypeRef   tr,                     // TypeRef to resolve.
    IMetaModelCommon *pCommon,          // Scope in which the TypeRef is defined.
    REFIID        riid, 
    IUnknown    **ppIScope,
    mdTypeDef    *ptd)                    // [OUT] typedef
{
    WCHAR    *temp;                        // Used as a parsing temp.
    int        iTmp;
    bool    bContinue;                    // Flag to check if the for loop should end.
    LPWSTR    wzSaveClassname = NULL;     // Saved offset into the class name string.
    
    // Process the class name appending each segment of the name to the
    // directory until we find a DLL.
    PathString dir;
    if (!directory.EndsWith(DIRECTORY_SEPARATOR_CHAR_W))
    {
        directory.Append(DIRECTORY_SEPARATOR_CHAR_W);
    }

    for(;;)
    {
        bContinue = false;
        dir.Set(directory);

        if ((temp = wcschr(wzClassname, NAMESPACE_SEPARATOR_WCHAR)) != NULL)
        {
            *temp = W('\0');  //terminate with null so that it can be appended
            dir.Append(wzClassname);
            *temp = NAMESPACE_SEPARATOR_WCHAR;   //recover the '.'

            wzClassname = temp+1;
            // Check if a directory by this name exists.
            DWORD iAttrs = WszGetFileAttributes(dir);
            if (iAttrs != 0xffffffff && (iAttrs & FILE_ATTRIBUTE_DIRECTORY))
            {
                // Next element in the class spec.
                bContinue = true;
                wzSaveClassname = wzClassname;
            }
        }
        else
        {
            dir.Append(wzClassname);

            // Advance past the class name.
            iTmp = (int)wcslen(wzClassname);
            wzClassname += iTmp;
        }

        // Try to load the image.
        dir.Append(W(".dll"));
       
        // OpenScope given the dll name and make sure that the class is defined in the module.
        if ( SUCCEEDED( CORPATHService::FindTypeDef(dir, tr, pCommon, riid, ppIScope, ptd) ) )
        {
            return (S_OK);
        }

        // If we didn't find the dll, try some more.
        while (*wzClassname != W('\0'))
        {
            // Find the length of the next class name element.
            if ((temp = wcschr(wzClassname, NAMESPACE_SEPARATOR_WCHAR)) == NULL)
            {
                temp = wzClassname + wcslen(wzClassname);
            }

            // Tack on ".element.dll"
            SString::Iterator iter = dir.End();
            BOOL findperiod = dir.FindBack(iter, NAMESPACE_SEPARATOR_WCHAR);
            _ASSERTE(findperiod);
            iter++;
            dir.Truncate(iter);
            
            WCHAR save = *temp;
            *temp      = W('\0');
            dir.Append(wzClassname);  //element
            *temp = save;
            
            // Try to load the image.
            dir.Append(W(".dll"));
           
            // OpenScope given the dll name and make sure that the class is defined in the module.
            if ( SUCCEEDED( CORPATHService::FindTypeDef(dir, tr, pCommon, riid, ppIScope, ptd) ) )
            {
                return (S_OK);
            }

            // Advance to the next class name element.
            wzClassname = temp;
            if (*wzClassname != '\0')
                ++wzClassname;
        }
//.........这里部分代码省略.........