RAII手法封装互斥锁

RAII手法是 Resource Acquisition is Initialization 的缩写，意为“资源获取即初始化”，在使用智能指针时也使用，下面是针对互斥量时的实现，

 #include <iostream>
 #include <pthread.h>

 using namespace std;

 class MutexLock
 {
 public:
     MutexLock()
     {
         pthread_mutex_init(&mutex_, NULL);
     }

     ~MutexLock()
     {
         pthread_mutex_destroy(&mutex_);
     }

     void Lock()
     {
         pthread_mutex_lock(&mutex_);
     }

     void Unlock()
     {
         pthread_mutex_unlock(&mutex_);
     }

 private:
     MutexLock(const MutexLock&);
     MutexLock& operator=(const MutexLock&);
     pthread_mutex_t mutex_;
 };

 class MutexLockGuard
 {
 public:
     explicit MutexLockGuard(MutexLock& mutex): mutex_(mutex)
     {
         mutex_.Lock();
     }

     ~MutexLockGuard()
     {
         mutex_.Unlock();
     }

 private:
     MutexLockGuard(const MutexLockGuard&);
     MutexLockGuard& operator=(const MutexLockGuard&);

     MutexLock& mutex_;
 };

 class Foo
 {
 public:
     void print()
     {
         MutexLockGuard lock(mutex_);
         cout << "Hello" << endl;
     }

 private:
     MutexLock mutex_;
 };