ATL对象多线程访问临界锁的实现
1. 几个临界区类
ATL将Windows临界区封装了一下，即CComCriticalSection和CComAutoCriticalSection类。两者的实现如下(精简)：
class CComCriticalSection
{
public:
CComCriticalSection()
{ memset(&m_sec, 0, sizeof(CRITICAL_SECTION)); }
HRESULT Lock()
{ EnterCriticalSection(&m_sec); return S_OK; }
HRESULT Unlock()
{ LeaveCriticalSection(&m_sec); return S_OK; }
HRESULT Init()
{
InitializeCriticalSection(&m_sec);
return S_OK;
}
HRESULT Term()
{ DeleteCriticalSection(&m_sec); return S_OK; }
CRITICAL_SECTION m_sec;
};
class CComAutoCriticalSection : public CComCriticalSection
{
public:
CComAutoCriticalSection()
{ HRESULT hr = CComCriticalSection::Init(); }
~CComAutoCriticalSection()
{ CComCriticalSection::Term(); }
private:
HRESULT Init();
HRESULT Term();
};
{
public:
CComCriticalSection()
{ memset(&m_sec, 0, sizeof(CRITICAL_SECTION)); }
HRESULT Lock()
{ EnterCriticalSection(&m_sec); return S_OK; }
HRESULT Unlock()
{ LeaveCriticalSection(&m_sec); return S_OK; }
HRESULT Init()
{
InitializeCriticalSection(&m_sec);
return S_OK;
}
HRESULT Term()
{ DeleteCriticalSection(&m_sec); return S_OK; }
CRITICAL_SECTION m_sec;
};
class CComAutoCriticalSection : public CComCriticalSection
{
public:
CComAutoCriticalSection()
{ HRESULT hr = CComCriticalSection::Init(); }
~CComAutoCriticalSection()
{ CComCriticalSection::Term(); }
private:
HRESULT Init();
HRESULT Term();
};
