#ifndef THREADPOOL_H
#define THREADPOOL_H
#include <list>
#include <cstdio>
#include <exception>
#include <pthread.h>
//引用前文线程同步机制的封装包
#include "locker.h"
/*
* 线程池类,将它定义为模板类是为了代码复用,模板参数T是任务类
*/
template< typename T >
class threadpool
{
public:
/*
* 参数thread_number是线程池中线程的数量,max_requests是请求队列中最多允许的,
* 等待处理的请求数量
*/
threadpool( int thread_number = 8, int max_requests = 10000 );
~threadpool();
/*往请求队列中添加任务*/
bool append( T* request );
private:
/*工作线程运行的函数,它不断从队列中取出任务并执行之*/
static void* worker( void* arg );
void run();
private:
int m_thread_number;//线程池中线程数
int m_max_requests;//请求队列中允许的最大请求数
pthread_t* m_threads;//描述线程池的数组,其大小为m_thread_number
std::list< T* > m_workqueue;//请求队列
locker m_queuelocker;//保护请求队列的互斥锁
sem m_queuestat;//是否有任务需要处理
bool m_stop;//是否结束线程
};
template< typename T >
threadpool< T >::threadpool( int thread_number, int max_requests ) :
m_thread_number( thread_number ), m_max_requests( max_requests ), m_stop( false ), m_threads( NULL )
{
if( ( thread_number <= 0 ) || ( max_requests <= 0 ) )
{
throw std::exception();
}
m_threads = new pthread_t[ m_thread_number ];
if( ! m_threads )
{
throw std::exception();
}
/*创建thread_number个线程,并将它们都设置为脱离线程*/
for ( int i = 0; i < thread_number; ++i )
{
printf( "create the %dth thread\n", i );
if( pthread_create( m_threads + i, NULL, worker, this ) != 0 )
{
delete [] m_threads;
throw std::exception();
}
if( pthread_detach( m_threads[i] ) )
{
delete [] m_threads;
throw std::exception();
}
}
}
template< typename T >
threadpool< T >::~threadpool()
{
delete [] m_threads;
m_stop = true;
}
template< typename T >
bool threadpool< T >::append( T* request )
{
/*操作工作队列时一定要加锁,因为它被所有线程共享*/
m_queuelocker.lock();
if ( m_workqueue.size() > m_max_requests )
{
m_queuelocker.unlock();
return false;
}
m_workqueue.push_back( request );
m_queuelocker.unlock();
m_queuestat.post();
return true;
}
template< typename T >
void* threadpool< T >::worker( void* arg )
{
threadpool* pool = ( threadpool* )arg;
pool->run();
return pool;
}
template< typename T >
void threadpool< T >::run()
{
while ( ! m_stop )
{
m_queuestat.wait();
m_queuelocker.lock();
if ( m_workqueue.empty() )
{
m_queuelocker.unlock();
continue;
}
T* request = m_workqueue.front();
m_workqueue.pop_front();
m_queuelocker.unlock();
if ( ! request )
{
continue;
}
request->process();
}
}
#endif
Linux下用半同步/半反应实现堆线程池
最新推荐文章于 2023-06-24 22:11:34 发布