ATL Internals 2ed复习.chapter 4.Debugging

ASSERT

#ifndef ATLASSERT
#define ATLASSERT(expr) _ASSERTE(expr)
#endif

上述这个宏依赖CRT

传输到debug output

inline void _cdecl AtlTrace(LPCSTR pszFormat, ...)
inline void _cdecl AtlTrace(LPCWSTR pszFormat, ...)

例子：

HRESULT CPenguin::FinalConstruct() {
ATLTRACE(__TEXT("%d+%d= %d\n"), 2, 2, 2+2);
}

还可以提示级别：

void AtlTrace2(DWORD_PTR dwCategory, UINT nLevel,
LPCSTR pszFormat, ...)
void AtlTrace2(DWORD_PTR dwCategory, UINT nLevel,
LPCWSTR pszFormat, ...)

在ATL内部已经制定了一套Category

#ifdef _DEBUG
#define DECLARE_TRACE_CATEGORY( name ) \
extern ATL::CTraceCategory name;
#else
#define DECLARE_TRACE_CATEGORY( name ) const DWORD_PTR name = 0;
#endif

DECLARE_TRACE_CATEGORY( atlTraceGeneral )
DECLARE_TRACE_CATEGORY( atlTraceCOM )
DECLARE_TRACE_CATEGORY( atlTraceQI )
DECLARE_TRACE_CATEGORY( atlTraceRegistrar )
DECLARE_TRACE_CATEGORY( atlTraceRefcount )
DECLARE_TRACE_CATEGORY( atlTraceWindowing )
DECLARE_TRACE_CATEGORY( atlTraceControls )
DECLARE_TRACE_CATEGORY( atlTraceHosting )
DECLARE_TRACE_CATEGORY( atlTraceDBClient )
DECLARE_TRACE_CATEGORY( atlTraceDBProvider )
DECLARE_TRACE_CATEGORY( atlTraceSnapin )
DECLARE_TRACE_CATEGORY( atlTraceNotImpl )
DECLARE_TRACE_CATEGORY( atlTraceAllocation )
DECLARE_TRACE_CATEGORY( atlTraceException )
DECLARE_TRACE_CATEGORY( atlTraceTime )
DECLARE_TRACE_CATEGORY( atlTraceCache )
DECLARE_TRACE_CATEGORY( atlTraceStencil )
DECLARE_TRACE_CATEGORY( atlTraceString )
DECLARE_TRACE_CATEGORY( atlTraceMap )
DECLARE_TRACE_CATEGORY( atlTraceUtil )
DECLARE_TRACE_CATEGORY( atlTraceSecurity )
DECLARE_TRACE_CATEGORY( atlTraceSync )
DECLARE_TRACE_CATEGORY( atlTraceISAPI )

// atlTraceUser categories are no longer needed.
// Just declare your own trace category using CTraceCategory.
DECLARE_TRACE_CATEGORY( atlTraceUser )
DECLARE_TRACE_CATEGORY( atlTraceUser2 )
DECLARE_TRACE_CATEGORY( atlTraceUser3 )
DECLARE_TRACE_CATEGORY( atlTraceUser4 )

#pragma deprecated( atlTraceUser )
#pragma deprecated( atlTraceUser2 )
#pragma deprecated( atlTraceUser3 )
#pragma deprecated( atlTraceUser4 )

用户可以这样使用：

CTraceCategory PenguinTraces( "CPenguin trace", 1 );
...
STDMETHODIMP CPenguin::Fly() {
ATLTRACE2(PenguinTraces,   2,
_T("IBird::Fly\n"));
ATLTRACE2(PenguinTraces,   42,
_T("Hmmm... Penguins can't fly...\n"));
ATLTRACE2(atlTraceNotImpl, 0,
_T("IBird::Fly not implemented!\n"));
return E_NOTIMPL;
}

当然还有更简便的方法，因为ATL已经有了：

#define ATLTRACENOTIMPL(funcname) \
ATLTRACE2(atlTraceNotImpl, 2, \
_T("ATL: %s not implemented.\n"), funcname); \
return E_NOTIMPL

所以：

STDMETHOD(SetMoniker)(DWORD, IMoniker*) {
ATLTRACENOTIMPL(_T("IOleObjectImpl::SetMoniker"));
}

Tracing Calls to QueryInterface

在编译时指定_ATL_DEBUG_QI，则可以跟踪QueryInterface

Tracing Calls to AddRef and Release

在编译时指定_ATL_DEBUG_INTERFACES，则可以跟踪QueryInterface,AddRef,Release，并且可以检验是否有LEAK

使用_AtlDebugInterfacesModule可以指定break，例如：

extern "C"
BOOL WINAPI DllMain(HINSTANCE hInstance, DWORD dwReason,
LPVOID lpReserved) {
hInstance;
BOOL b = _AtlModule.DllMain(dwReason, lpReserved);
// Trace down interface leaks
#ifdef _ATL_DEBUG_INTERFACES
_AtlDebugInterfacesModule.m_nIndexBreakAt = 4;
#endif
return b;
}

_ATL_DEBUG_REFCOUNT

对于ATL3之前的版本，等效于_ATL_DEBUG_INTERFACES