C语言实现一个简单的线程池

（代码有参考网上的一些实现）还有几个功能需要慢慢的实现和一些bug需要改，比如实现线程池的动态增长：

详细请看我的github： https://github.com/chengshuguang/thread-pool

thread_pool.h

#ifndef THREAD_POOL_H#define THREAD_POOL_H#include <stdio.h>#include <stdlib.h>#include <unistd.h>#include <string.h>#include <pthread.h>typedef struct task{	void *(*taskfunc)(void *arg);//声明一个函数指针	void *arg;//函数的参数	struct task *next;}task;typedef struct thread_pool{	task *task_queue_head;//任务队列	task *task_queue_end;//指向任务队列结尾	int task_queue_size;	pthread_t *thread_queue;//线程队列	int thread_num;	int idle_thread_num;//空闲线程数	int is_pool_destroyed;	pthread_mutex_t queue_mutex;//用来互斥访问任务队列	pthread_cond_t queue_cond;}thread_pool;#ifdef __cplusplusextern "C"{#endifextern thread_pool *pool;extern int thread_pool_init(int thread_pool_size);//extern void * thread_pool_entrance(void *arg);extern int thread_pool_add_task(void *(*taskfunc)(void *arg), void *arg);extern int thread_pool_destroy();#ifdef __cplusplus}#endif#endif //THREAD_POOL_H

thread_pool.c

#include "thread_pool.h"#include <pthread.h>thread_pool *pool = NULL;void * thread_pool_entrance(void *arg){	int thread_id = (int)arg;	printf("thread %d is created/n",thread_id);	while(1)	{		pthread_mutex_lock(&(pool->queue_mutex));		while(pool->task_queue_size == 0 && !pool->is_pool_destroyed)//必须用while，防止假唤醒		{			pthread_cond_wait(&(pool->queue_cond),&(pool->queue_mutex));//等待的时候会解锁，唤醒后加锁		}		if(pool->is_pool_destroyed)		{			printf("thread %d exit!!!/n",thread_id);			pthread_mutex_unlock(&(pool->queue_mutex));//中途退出最容易出错，注意要解锁			pthread_exit(NULL);		}		pool->idle_thread_num--;//线程进入忙碌状态		//从任务队列中取出任务		task *work;		work = pool->task_queue_head;		pool->task_queue_head = pool->task_queue_head->next;		if(pool->task_queue_head == NULL)			pool->task_queue_end = NULL;		pool->task_queue_size--;		pthread_mutex_unlock(&(pool->queue_mutex));		//回调函数		(*(work->taskfunc))(work->arg);		pool->idle_thread_num++;//线程空闲	}	return NULL;}int thread_pool_init(int thread_pool_size){	pool = (thread_pool *)malloc(sizeof(thread_pool));//不要最先给线程池分配空间	pool->is_pool_destroyed = 0;	pool->task_queue_head = NULL;	pool->task_queue_end = NULL;	pool->task_queue_size = 0;	pool->thread_num = thread_pool_size;	pool->thread_queue = (pthread_t *)malloc(thread_pool_size * sizeof(pthread_t));	pool->idle_thread_num = thread_pool_size;	//创建线程	int i, ret;	for(i=0; i<thread_pool_size; i++)	{		ret = pthread_create(&(pool->thread_queue[i]), NULL, thread_pool_entrance, (void *)i);		if(ret < 0)		{			printf("thread create error!!!/n");			thread_pool_destroy();//注意销毁，避免内存泄漏			return -1;		}	}	pthread_mutex_init(&(pool->queue_mutex), NULL);	pthread_cond_init(&(pool->queue_cond), NULL);	return 0;}typedef void *(*taskfunc)(void *arg);int thread_pool_add_task(taskfunc func, void *arg){	task *newtask;	newtask = (task *)malloc(sizeof(task));	newtask->taskfunc = func;	newtask->arg = arg;	newtask->next = NULL;	pthread_mutex_lock(&(pool->queue_mutex));	if(pool->task_queue_head == NULL)	{		pool->task_queue_head = pool->task_queue_end = newtask;	}	else	{		pool->task_queue_end = pool->task_queue_end->next = newtask;	}	pool->task_queue_size++;	pthread_cond_signal(&(pool->queue_cond));	pthread_mutex_unlock(&(pool->queue_mutex));	return 0;}int thread_pool_destroy(){	if(pool->is_pool_destroyed)//防止多次销毁		return -1;	pool->is_pool_destroyed = 1;	pthread_cond_broadcast(&(pool->queue_cond));//通知所有线程线程池销毁了	int i;	for(i=0; i<pool->thread_num; i++)//等待线程全部执行完		pthread_join(pool->thread_queue[i], NULL);	//销毁任务队列	task *temp = NULL;	while(pool->task_queue_head)	{		temp = pool->task_queue_head;		pool->task_queue_head = pool->task_queue_head->next;		free(temp);	}	//pool->task_queue_head = NULL；	//pool->task_queue_end = NULL；	//销毁线程队列	free(pool->thread_queue);	pool->thread_queue = NULL;	pthread_mutex_destroy(&(pool->queue_mutex));	pthread_cond_destroy(&(pool->queue_cond));	free(pool);	pool = NULL;	return 0;}

#include "thread_pool.h"#include <stdio.h>void *taskprocess(void *arg){	printf("aaaaaadoing tasksaaaaaaaaa/n");	usleep(1000);	return NULL;}int main(){	thread_pool_init(5);	int i;	for(i=1; i<=10; i++)	{		thread_pool_add_task(taskprocess,(void *)i);		usleep(1000);	}	sleep(1);	thread_pool_destroy();	return 0;}