scope guard

scopeGuard.h

#ifndef SCLOUD_SCOPE_GUARD_H_
#define SCLOUD_SCOPE_GUARD_H_

#include <functional>

namespace scloud{
class ScopeGuard
{
public:
	explicit ScopeGuard(std::function<void(void)> onExitScope)
		: doExit_(onExitScope), cancel_(false){}

	~ScopeGuard() {
		if(!cancel_) {
			doExit_();
		}
	}

	void cancel() {
		cancel_ = true;
	}

private:
	//disable copy
	ScopeGuard(const ScopeGuard&); 
	void operator=(const ScopeGuard&);
	
	std::function<void(void)> doExit_;
	bool cancel_;
};
}//end namespace

#define SCLOUD_CAT_STRING(name, line)    	  name##line
#define SCLOUD_XSOCPEGUARD_LOCK_CAT(name, line)   SCLOUD_CAT_STRING(name,line)
#define SCLOUD_SCOPE_EXIT                         scloud::ScopeGuard SCLOUD_XSOCPEGUARD_LOCK_CAT(ScopeGuard, __LINE__)

#endif //SCLOUD_SCOPE_GUARD_H_



/*!
	@brief how to use it.
	
	①
	SomeClass * p = new SomeClass;
	SCLOUD_SCOPE_EXIT([](){delete p;});
	...
	
	②
	HANDLE h = CreateFile(...);
	scloud::ScopeGuard guard([](){CloseHandle(h);};);
	if (h == INVALIDE_HANDLE) {
		guard.cancel();
	}
	
*/