c++11日志练习

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使用c++11 写个日志类

主要练习 线程 互斥量的使用

代码如下:

#include "stdafx.h"

#include "Logger.h"

#include <fstream>

#include <iostream>



Logger::Logger(const string& filepath):

filePath_(filepath)

{



}



Logger::~Logger()

{

	

	thread_.join();

}



bool Logger::init()

{

	bool bRet = false;

	thread_ = thread{ &Logger::LogThreadFunc, this };

	unique_lock<mutex> lock(mutexStarted_);

	condVarStarted_.wait(lock);



	bRet = true;

	return bRet;

}



void Logger::Log(const std::string& content)

{

	unique_lock<mutex> lock(mutex_);

	queue_.push(content);



}





void Logger::LogThreadFunc()

{

	ofstream ofs(filePath_);

	if (ofs.fail()) {

		cerr << "Failed to open logfile." << endl;

		return;

	}



	cout << "enter thread" << endl;

	unique_lock<mutex> lock(mutex_,std::defer_lock);

	condVarStarted_.notify_all();



	while (true){

		lock.lock();

		condVar_.wait(lock);

		lock.unlock();



		while (true){

			lock.lock();

			if (queue_.empty()) {

				lock.unlock();

				break;

			}

			else {

				ofs << queue_.front() << endl;

				queue_.pop();

			}

			lock.unlock();

		}

		if (bExit_){

			break;

		}

	}





}

　　

#ifndef LOGGER_H__

#define LOGGER_H__





#include <queue>

#include <string>

#include <thread>

#include <mutex>

#include <condition_variable>



#define DEFAULT_FILE_NAME	"test.dat"



using namespace std;



class Logger{

public:

	Logger(const string& filepath = DEFAULT_FILE_NAME);

	virtual ~Logger();

	bool init();



	void Log(const std::string& content);

	void LogThreadFunc();

	void SetExitFlag(){

		bExit_ = true;

		condVar_.notify_all();

	};

private:

	string filePath_;

	bool bExit_;

	std::condition_variable condVar_;

	std::condition_variable condVarStarted_;

	std::thread thread_;

	std::mutex mutex_;

	std::mutex mutexStarted_;

	std::queue<std::string> queue_;

	Logger& operator=(const Logger& rhs);

};







#endif 

　　测试代码如下:

// 1111.cpp : 定义控制台应用程序的入口点。

//



#include "stdafx.h"

#include "Logger.h"

#include <iostream>

#include <sstream>

#include <thread>

#include <vector>







void logSomeMessages(int id, Logger& logger)

{

	for (int i = 0; i < 100; ++i) {

		stringstream ss;

		ss << "Log test " << i << " from thread " << id;

		logger.Log(ss.str());

	}

}



int _tmain(int argc, _TCHAR* argv[])

{

	Logger log;

	log.init();



	vector<thread> threads;

	// Create a few threads all working with the same Logger instance.

	for (int i = 0; i < 100; ++i) {

		threads.push_back(thread{ logSomeMessages, i, ref(log) });

	}



	for (auto& t : threads) {

		t.join();

	}



	log.SetExitFlag();

	return 0;

}