FIX: ATL In-Proc Servers Load Twice If Using Short Filename

ID: Q218475

The information in this article applies to:

SYMPTOMS

Active Template Library (ATL) uses the DECLARE_REGISTRY_RESOURCEID macro and registers the COM object with the short filename when registering an in-proc COM object. This causes such problems as not hitting breakpoints or seeing two copies of global data.


CAUSE

Windows NT's LoadLibrary incorrectly loads a DLL twice if a long and short filename are used. In an ATL DLL COM server where you are also implicitly linked to the DLL, COM uses the short filename where the Windows NT loader uses the long filename when loading the DLL.


RESOLUTION

In the atlbase.h file, override the following functions: AtlModuleUpdateRegistryFromResourceD (for non-static builds) and both versions of CComModule::UpdateRegistryFromResourceS (for static builds). In addition, replace this code sample: 


// Convert to short path to work around bug in Windows NT 4.0's CreateProcess
TCHAR szModuleShort[_MAX_PATH];
GetShortPathName(szModule, szModuleShort, _MAX_PATH);
LPOLESTR pszModule = T2OLE(szModuleShort);
with the following: 

LPOLESTR pszModule;
if ((pM->m_hInst == NULL) || (pM->m_hInst == GetModuleHandle(NULL))) // register as EXE
{
    // Convert to short path to work around bug in NT4's CreateProcess
    TCHAR szModuleShort[_MAX_PATH];
    int cbShortName = GetShortPathName(szModule, szModuleShort, _MAX_PATH);

    if (cbShortName == _MAX_PATH)
        return E_OUTOFMEMORY;

    pszModule = (cbShortName == 0 || cbShortName ==
        ERROR_INVALID_PARAMETER) ? T2OLE(szModule) : T2OLE(szModuleShort);
}
else
    pszModule = T2OLE(szModule);
In the new code, the DLL servers are registered using the long filename whereas the .exe file servers are registered using the short file name.


STATUS

Microsoft has confirmed this to be a bug in the Microsoft products listed at the beginning of this article.

This bug was corrected in Visual Studio 6.0 Service Pack 3.

For more information about Visual Studio 6.0 Service Packs, please see the following articles in the Microsoft Knowledge Base:


Q194022 INFO: Visual Studio 6.0 Service Packs, What, Where, Why

Q194295 HOWTO: Tell That Visual Studio 6.0 Service Packs Are Installed


MORE INFORMATION

This problem can be solved by overriding the registration functions in CComModule. The resolution shown here is provided to handle the general registration process for both the .exe file and DLL COM servers even though the steps are shown specifically for DLL servers.

  1. Derive a class from CComModule, CDllModule, and declare it as shown in Stdafx.h:
    
class CDllModule : public CComModule
{
public:
#ifdef _ATL_STATIC_REGISTRY
    // Statically linking to Registry component.

    HRESULT WINAPI UpdateRegistryFromResourceS(UINT nResID,
        BOOL bRegister, struct _ATL_REGMAP_ENTRY* pMapEntries = NULL);
    HRESULT WINAPI UpdateRegistryFromResourceS(LPCTSTR lpszRes,
        BOOL bRegister, struct _ATL_REGMAP_ENTRY* pMapEntries = NULL);

#else

    HRESULT WINAPI UpdateRegistryFromResourceD(LPCTSTR lpszRes,
        BOOL bRegister, struct _ATL_REGMAP_ENTRY* pMapEntries = NULL);
    HRESULT WINAPI UpdateRegistryFromResourceD(UINT nResID,
        BOOL bRegister, struct _ATL_REGMAP_ENTRY* pMapEntries = NULL);

#endif
};

extern CDllModule _Module;


  2. In Myproject.cpp, change CComModule to CDllModule as follows:
    
CDllModule _Module;


  3. Add the following to the includes at the top of the file:
    
#ifdef _ATL_STATIC_REGISTRY
#include <statreg.h>
#endif


  4. In Myproject.cpp, add the following code to the end of the file:
    
#ifdef _ATL_STATIC_REGISTRY
#include <statreg.h>

// Statically linking to Registry Ponent
inline HRESULT WINAPI CDllModule::UpdateRegistryFromResourceS(UINT nResID, BOOL bRegister,
    struct _ATL_REGMAP_ENTRY* pMapEntries)
{
    USES_CONVERSION;
    ATL::CRegObject ro;
    TCHAR szModule[_MAX_PATH];
    GetModuleFileName(_pModule->GetModuleInstance(), szModule, _MAX_PATH);

    LPOLESTR pszModule;
    if ((pM->m_hInst == NULL) || (pM->m_hInst == GetModuleHandle(NULL))) // register as EXE
    {
        // Convert to short path to work around bug in NT4's CreateProcess
        TCHAR szModuleShort[_MAX_PATH];
        int cbShortName = GetShortPathName(szModule, szModuleShort, _MAX_PATH);

        if (cbShortName == _MAX_PATH)
            return E_OUTOFMEMORY;

        pszModule = (cbShortName == 0 || cbShortName == ERROR_INVALID_PARAMETER) ? T2OLE(szModule) : T2OLE(szModuleShort);
    }
    else
        pszModule = T2OLE(szModule);

    int nLen = ocslen(pszModule);
    LPOLESTR pszModuleQuote = (LPOLESTR)alloca((nLen*2+1)*sizeof(OLECHAR));
    ReplaceSingleQuote(pszModuleQuote, pszModule);
    ro.AddReplacement(OLESTR("Module"), pszModuleQuote);
    if (NULL != pMapEntries)
    {
        while (NULL != pMapEntries->szKey)
        {
            ATLASSERT(NULL != pMapEntries->szData);
            ro.AddReplacement(pMapEntries->szKey, pMapEntries->szData);
                pMapEntries++;
        }
    }

    LPCOLESTR szType = OLESTR("REGISTRY");
    return (bRegister) ? ro.ResourceRegister(pszModule, nResID, szType) :
        ro.ResourceUnregister(pszModule, nResID, szType);
}

inline HRESULT WINAPI CDllModule::UpdateRegistryFromResourceS(LPCTSTR lpszRes, BOOL bRegister,
    struct _ATL_REGMAP_ENTRY* pMapEntries)
{
    USES_CONVERSION;
    ATL::CRegObject ro;
    TCHAR szModule[_MAX_PATH];
    GetModuleFileName(_pModule->GetModuleInstance(), szModule, _MAX_PATH);

    LPOLESTR pszModule;
    if ((pM->m_hInst == NULL) || (pM->m_hInst == GetModuleHandle(NULL))) // register as EXE
    {
        // Convert to short path to work around bug in NT4's CreateProcess
        TCHAR szModuleShort[_MAX_PATH];
        int cbShortName = GetShortPathName(szModule, szModuleShort, _MAX_PATH);

        if (cbShortName == _MAX_PATH)
            return E_OUTOFMEMORY;

        pszModule = (cbShortName == 0 || cbShortName == ERROR_INVALID_PARAMETER) ? T2OLE(szModule) : T2OLE(szModuleShort);
    }
    else
        pszModule = T2OLE(szModule);

    int nLen = ocslen(pszModule);
    LPOLESTR pszModuleQuote = (LPOLESTR)alloca((nLen*2+1)*sizeof(OLECHAR));
    ReplaceSingleQuote(pszModuleQuote, pszModule);
    ro.AddReplacement(OLESTR("Module"), pszModuleQuote);
    if (NULL != pMapEntries)
    {
        while (NULL != pMapEntries->szKey)
        {
            ATLASSERT(NULL != pMapEntries->szData);
            ro.AddReplacement(pMapEntries->szKey, pMapEntries->szData);
            pMapEntries++;
        }
    }

    LPCOLESTR szType = OLESTR("REGISTRY");
    LPCOLESTR pszRes = T2COLE(lpszRes);
    return (bRegister) ? ro.ResourceRegisterSz(pszModule, pszRes, szType) :
			ro.ResourceUnregisterSz(pszModule, pszRes, szType);
}

#else

ATLINLINE ATLAPI MyAtlModuleUpdateRegistryFromResourceD(_ATL_MODULE* pM, LPCOLESTR lpszRes,
    BOOL bRegister, struct _ATL_REGMAP_ENTRY* pMapEntries, IRegistrar* pReg = NULL)
{
    USES_CONVERSION;
    ATLASSERT(pM != NULL);
    HRESULT hRes = S_OK;
    CComPtr<IRegistrar> p;
    if (pReg != NULL)
        p = pReg;
    else
    {
        hRes = CoCreateInstance(CLSID_Registrar, NULL,
            CLSCTX_INPROC_SERVER, IID_IRegistrar, (void**)&p);
    }
    if (SUCCEEDED(hRes))
    {
        TCHAR szModule[_MAX_PATH];
        GetModuleFileName(pM->m_hInst, szModule, _MAX_PATH);

        LPOLESTR pszModule;
        if ((pM->m_hInst == NULL) || (pM->m_hInst == GetModuleHandle(NULL))) // register as EXE
        {
            // Convert to short path to work around bug in NT4's CreateProcess
            TCHAR szModuleShort[_MAX_PATH];
            int cbShortName = GetShortPathName(szModule, szModuleShort, _MAX_PATH);

            if (cbShortName == _MAX_PATH)
                return E_OUTOFMEMORY;

            pszModule = (cbShortName == 0 || cbShortName == ERROR_INVALID_PARAMETER) ? T2OLE(szModule) : T2OLE(szModuleShort);
        }
        else
            pszModule = T2OLE(szModule);

        int nLen = ocslen(pszModule);
        LPOLESTR pszModuleQuote = (LPOLESTR)alloca((nLen*2+1)*sizeof(OLECHAR));
        CComModule::ReplaceSingleQuote(pszModuleQuote, pszModule);
        p->AddReplacement(OLESTR("Module"), pszModuleQuote);

        if (NULL != pMapEntries)
        {
            while (NULL != pMapEntries->szKey)
            {
                ATLASSERT(NULL != pMapEntries->szData);
                p->AddReplacement((LPOLESTR)pMapEntries->szKey,
                    (LPOLESTR)pMapEntries->szData);
                pMapEntries++;
            }
        }
        LPCOLESTR szType = OLESTR("REGISTRY");
        if (HIWORD(lpszRes)==0)
        {
            if (bRegister)
                hRes = p->ResourceRegister(pszModule, ((UINT)LOWORD((DWORD)lpszRes)), szType);
            else
                hRes = p->ResourceUnregister(pszModule, ((UINT)LOWORD((DWORD)lpszRes)), szType);
        }
        else
        {
            if (bRegister)
                hRes = p->ResourceRegisterSz(pszModule, lpszRes, szType);
            else
                hRes = p->ResourceUnregisterSz(pszModule, lpszRes, szType);
        }
    }
    return hRes;
}

// Resource-based Registration
HRESULT WINAPI CDllModule::UpdateRegistryFromResourceD(LPCTSTR lpszRes, BOOL bRegister,
    struct _ATL_REGMAP_ENTRY* pMapEntries)
{
    USES_CONVERSION;
    return MyAtlModuleUpdateRegistryFromResourceD(this, T2COLE(lpszRes), bRegister,
        pMapEntries);
}
HRESULT WINAPI CDllModule::UpdateRegistryFromResourceD(UINT nResID, BOOL bRegister,
    struct _ATL_REGMAP_ENTRY* pMapEntries)
{
    return MyAtlModuleUpdateRegistryFromResourceD(this,
        (LPCOLESTR)MAKEINTRESOURCE(nResID), bRegister, pMapEntries);
}


#endif


  5. Save the changes and rebuild all.




REFERENCES

Q193513 BUG: Breakpoints Not Hit in ATL MMC Snap-In

Q179690 FIX: Launching COM Server with Long File Name Returns 0x80080005

© Microsoft Corporation 1999, All Rights Reserved.
Contributions by Adam Kim, Microsoft Corporation

Additional query words: 


Keywords          : kbservicepack kbCOMt kbDLL kbRegistry kbVC600 kbATL300 kbVS600sp3fix 
Version           : WINDOWS:3.0
Platform          : WINDOWS 
Issue type        : kbprb

Last Reviewed: May 19, 1999