一段簡單的Linux線程池代碼

實現web server時，通過建立一個線程池來並發處理用戶端的http請求，代碼如下：

 

for(i = 0; i < THREAD_POOL_SIZE; i++)<br />{<br />pthread_create(&thread_pool[i], NULL, (void*)&worker, (void*)i);<br />pthread_detach(thread_pool[i]);<br />}

 

線程並發處理如下：

void* worker(int n)<br />{<br />struct server_struct *request;<br />DebugMSG("Worker %d started!", n);<br />while(loop) // Global variable of "loop" indicates that server is running, if not set, quit<br />{<br />pthread_mutex_lock(&pool_mutex); // You should lock mutex before pthread_cond_wait call..<br />request = pop_request();<br />if (request == NULL) {<br />// No more jobs, go to sleep now<br />pthread_cond_wait(&new_request, &pool_mutex); // On pthread_cond_signal event pthread_cond_wait lock's mutex via pthread_mutex_lock<br />request = pop_request();<br />}<br />pthread_mutex_unlock(&pool_mutex); // so, you must unlock it.</p><p>if(request != NULL)<br />server(request);<br />pthread_cond_signal(&thread_free);<br />}</p><p>pthread_exit(NULL);<br />return NULL;<br />}</p><p>int push_request(struct server_struct* request)<br />{<br />int i, added = 0;</p><p>pthread_mutex_lock(&pool_mutex);<br />for(i = 0; (i < THREAD_POOL_SIZE)&&(!added); i++)<br />{<br />if(pool[i] == NULL)<br />{<br />pool[i] = request;<br />added = 1;<br />}<br />}<br />pthread_mutex_unlock(&pool_mutex);<br />if (added)<br />pthread_cond_signal(&new_request);<br />return added;<br />}</p><p>struct server_struct* pop_request()<br />{<br />int i;<br />struct server_struct *request = NULL;<br />for(i = 0; (i < THREAD_POOL_SIZE)&&(request == NULL); i++)<br />{<br /> if(pool[i] != NULL)<br />{<br />request = pool[i];<br />pool[i] = NULL;<br />}<br /> }<br />return request;<br />}