boost 线程同步速记

参考资料:

http://www.boost.org/doc/libs/1_57_0/doc/html/thread/synchronization.html

互斥量

boost::mutex

获取释放 , 尝试获取

boost::mutex  m_lock;
m_lock.lock();
/* do somthing that need thread safe */
m_lock.unlock();
// 尝试获取
if(m_lock.try_lock())
{
// 获取到了
}
else
{
// 获取失败
}  

基于作用域的自动lock和unlock

scope_lock , unique_lock

boost::mutex  m_lock;
{ boost::unique_lock<boost::mutex> guard(m_lock); /* do somthing that need thread safe */ }
/*out of above scope , the guard free and m_lock will be unlock automaticly*/

可以递归锁住的互斥量

boost::recursive_mutex

派生出可以被锁住的类

class BankAccount
: public basic_lockable_adapter<boost::recursive_mutex>
{
    int balance_;
public:
    void Deposit(int amount) {
        boost::lock_guard<BankAccount> guard(*this);
        balance_ += amount;
    }
    void Withdraw(int amount) {
        boost::lock_guard<BankAccount> guard(*this);
        balance_ -= amount;
    }
    int GetBalance() {
        boost::lock_guard<BankAccount> guard(*this);
        return balance_;
    }
};
//  实现特定的调用顺序不被打断
void ATMWithdrawal(BankAccount& acct, int sum) {
    boost::lock_guard<BankAccount> guard(acct);
    acct.Withdraw(sum);
    acct.Withdraw(2);
}

读写锁

可以重复上锁的互斥量shared_lock

class RWLock
{
    public:
        void ReadLock(){ m_lock.lock_shared();}
        void ReadUnlock(){ m_lock.unlock_shared();}
        void WriteLock() { m_lock.lock();}
        void WriteUnlock() { m_lock.unlock();}
    private:
        shared_lock m_lock;
}

条件变量

boost::condition_variable

获取

wait( boost::condition_variable)

提醒一个

boost::condition_variable::notify_one()

提醒所有

boost::condition_variable::notify_all()