locker.h

#ifndef LOCKER_H
#define LOCKER_H

#include <exception>
#include <pthread.h>
#include <semaphore.h>

/* 封装信号量的类*/
class sem{
public:
    sem() {
        if(sem_init(&m_sem, 0, 0) != 0) {
            throw std::exception();
        }
    }
    ~sem() {
        sem_destroy(&m_sem);
    }
    /* 等待信号量*/
    bool wait() {
        return sem_wait(&m_sem) == 0;
    }
    /* 增加信号量*/
    bool post() {
        return sem_post(&m_sem) == 0;
    }

private:
    sem_t m_sem;
};


/* 封装互斥锁的类*/
class locker{
public:
    locker() {
        if(pthread_mutex_init(&m_mutex, NULL) != 0) {
            throw std::exception();
        }
    }
    ~locker() {
        pthread_mutex_destroy(&m_mutex);
    }
    /* 获取互斥锁*/
    bool lock() {
        return pthread_mutex_lock(&m_mutex) == 0;
    }
    /* 释放互斥锁*/
    bool unlock() {
        return pthread_mutex_unlock(&m_mutex) == 0;
    }
private:
    pthread_mutex_t m_mutex;
};

/* 封装条件变量的类*/
class cond{
public:
    cond() {
        if(pthread_mutex_init(&m_mutex, NULL) != 0) {
            throw std::exception();
        }
        if(pthread_cond_init(&m_cond, NULL) != 0) {
            /* 构造函数中一旦出现问题，就应该立刻释放已经成功分配的资源*/
            pthread_mutex_destroy(&m_mutex);
            throw std::exception();
        }
    }
    ~cond() {
        pthread_mutex_destroy(&m_mutex);
        pthread_cond_destroy(&m_cond);
    }
    /* 等待条件变量*/
    bool wait() {
        int ret = 0;
        pthread_mutex_lock(&m_mutex);
        ret = pthread_cond_wait(&m_cond, &m_mutex);
        pthread_mutex_unlock(&m_mutex);
        return ret == 0;
    }
    /* 唤醒等待条件变量的线程*/
    bool signal() {
        return pthread_cond_signal(&m_cond) == 0;
    }
private:
    pthread_cond_t m_cond;
    pthread_mutex_t m_mutex;
};
#endif //LOCKER_H