int pthread_create(pthread_t *tidp, const pthread_attr_t *attr, (void*)(*start_rtn)(void *), void *arg); //創(chuàng)建
void pthread_exit(void *retval);　　　　　　　　　　　　//終止自身
int pthread_cancel(pthread_t tid); 　 　　　　　　　　 //終止其他.發(fā)送終止信號后目標(biāo)線程不一定終止，要調(diào)用join函數(shù)等待
int pthread_join(pthread_t tid, void **retval);　　 //阻塞并等待其他線程

int pthread_attr_init(pthread_attr_t *attr);　　　　　　　　　　 //初始化屬性
int pthread_attr_setdetachstate(pthread_attr_t *attr, int detachstate); //設(shè)置分離狀態(tài)
int pthread_attr_destroy(pthread_attr_t *attr);　　　　　　　　　　 //銷毀屬性

int pthread_mutex_init(pthread_mutex_t *restrict mutex, const pthread_mutexattr_t *restrict attr); //初始化鎖
int pthread_mutex_destroy(pthread_mutex_t *mutex); //銷毀鎖
int pthread_mutex_lock(pthread_mutex_t *mutex); //加鎖
int pthread_mutex_trylock(pthread_mutex_t *mutex); //嘗試加鎖，上面lock的非阻塞版本
int pthread_mutex_unlock(pthread_mutex_t *mutex); //解鎖

int pthread_cond_init(pthread_cond_t *cv, const pthread_condattr_t *cattr); //初始化
int pthread_cond_destroy(pthread_cond_t *cond);                 //銷毀 
int pthread_cond_wait(pthread_cond_t *cond, pthread_mutex_t *mutex);     //等待條件
int pthread_cond_signal(pthread_cond_t *cond);                 //通知,喚醒第一個調(diào)用pthread_cond_wait()而進入睡眠的線程

int pthread_equal(pthread_t t1, pthread_t t2); //比較線程ID
int pthread_detach(pthread_t tid);       //分離線程
pthread_t pthread_self(void);            //自身ID

#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>  //linux環(huán)境中多線程的頭文件，非C語言標(biāo)準(zhǔn)庫，編譯時最后要加 -lpthread 調(diào)用動態(tài)鏈接庫

//工作鏈表的結(jié)構(gòu)
typedef struct worker {
  void *(*process)(void *arg);  //工作函數(shù)
  void *arg;           //函數(shù)的參數(shù)
  struct worker *next;
}CThread_worker;

//線程池的結(jié)構(gòu)
typedef struct {
  pthread_mutex_t queue_lock;   //互斥鎖
  pthread_cond_t queue_ready;  //條件變量/信號量

  CThread_worker *queue_head;   //指向工作鏈表的頭結(jié)點，臨界區(qū)
  int cur_queue_size;       //記錄鏈表中工作的數(shù)量，臨界區(qū)

  int max_thread_num;       //最大線程數(shù)
  pthread_t *threadid;      //線程ID

  int shutdown;          //開關(guān)
}CThread_pool;

static CThread_pool *pool = NULL;  //一個線程池變量
int pool_add_worker(void *(*process)(void *arg), void *arg);  //負(fù)責(zé)向工作鏈表中添加工作
void *thread_routine(void *arg);  //線程例程

//線程池初始化
void pool_init(int max_thread_num)
{
  int i = 0;

  pool = (CThread_pool *) malloc (sizeof(CThread_pool));  //創(chuàng)建線程池

  pthread_mutex_init(&(pool->queue_lock), NULL);   //互斥鎖初始化，參數(shù)為鎖的地址
  pthread_cond_init( &(pool->queue_ready), NULL);   //條件變量初始化，參數(shù)為變量地址

  pool->queue_head = NULL;
  pool->cur_queue_size = 0;

  pool->max_thread_num = max_thread_num;
  pool->threadid = (pthread_t *) malloc(max_thread_num * sizeof(pthread_t));
  for (i = 0; i < max_thread_num; i++) {
    pthread_create(&(pool->threadid[i]), NULL, thread_routine, NULL); //創(chuàng)建線程, 參數(shù)為線程ID變量地址、屬性、例程、參數(shù)
  }

  pool->shutdown = 0;
}

//例程，調(diào)用具體的工作函數(shù)
void *thread_routine(void *arg)
{
  printf("starting thread 0x%x\n", (int)pthread_self());
  while(1) {
    pthread_mutex_lock(&(pool->queue_lock));  //從工作鏈表中取工作，要先加互斥鎖，參數(shù)為鎖地址

    while(pool->cur_queue_size == 0 && !pool->shutdown) {    //鏈表為空
      printf("thread 0x%x is waiting\n", (int)pthread_self());
      pthread_cond_wait(&(pool->queue_ready), &(pool->queue_lock));  //等待資源，信號量用于通知。會釋放第二個參數(shù)的鎖，以供添加；函數(shù)返回時重新加鎖。
    }

    if(pool->shutdown) {
      pthread_mutex_unlock(&(pool->queue_lock));     //結(jié)束開關(guān)開啟，釋放鎖并退出線程
      printf("thread 0x%x will exit\n", (int)pthread_self());
      pthread_exit(NULL);   //參數(shù)為void *
    }

    printf("thread 0x%x is starting to work\n", (int)pthread_self());

    --pool->cur_queue_size;
    CThread_worker *worker = pool->queue_head;
    pool->queue_head = worker->next;

    pthread_mutex_unlock (&(pool->queue_lock));   //獲取一個工作后釋放鎖
    (*(worker->process))(worker->arg);   //做工作
    free(worker);
    worker = NULL;
  }
  pthread_exit(NULL);
}

//銷毀線程池
int pool_destroy()
{
  if(pool->shutdown)   //檢測結(jié)束開關(guān)是否開啟，若開啟，則所有線程會自動退出
    return -1;
  pool->shutdown = 1;

  pthread_cond_broadcast( &(pool->queue_ready) );   //廣播，喚醒所有線程，準(zhǔn)備退出

  int i;
  for(i = 0; i < pool->max_thread_num; ++i)
    pthread_join(pool->threadid[i], NULL);   //主線程等待所有線程退出，只有join第一個參數(shù)不是指針，第二個參數(shù)類型是void **，接收exit的返回值，需要強制轉(zhuǎn)換
  free(pool->threadid);
  CThread_worker *head = NULL;
  while(pool->queue_head != NULL) {      //釋放未執(zhí)行的工作鏈表剩余結(jié)點
    head = pool->queue_head;
    pool->queue_head = pool->queue_head->next;
    free(head);
  }

  pthread_mutex_destroy(&(pool->queue_lock));   //銷毀鎖和條件變量
  pthread_cond_destroy(&(pool->queue_ready));

  free(pool);
  pool=NULL;
  return 0;
}

void *myprocess(void *arg)
{
  printf("threadid is 0x%x, working on task %d\n", (int)pthread_self(), *(int*)arg);
  sleep (1);
  return NULL;
}

//添加工作
int pool_add_worker(void *(*process)(void *arg), void *arg)
{
  CThread_worker *newworker = (CThread_worker *) malloc(sizeof(CThread_worker));
  newworker->process = process;  //具體的工作函數(shù)
  newworker->arg = arg;
  newworker->next = NULL;

  pthread_mutex_lock( &(pool->queue_lock) );   //加鎖

  CThread_worker *member = pool->queue_head;   //插入鏈表尾部
  if( member != NULL ) {
    while( member->next != NULL )
      member = member->next;
    member->next = newworker;
  }
  else {
    pool->queue_head = newworker;
  }
  ++pool->cur_queue_size;

  pthread_mutex_unlock( &(pool->queue_lock) );  //解鎖

  pthread_cond_signal( &(pool->queue_ready) );  //通知一個等待的線程
  return 0;
}

int main(int argc, char **argv)
{
  pool_init(3);  //主線程創(chuàng)建線程池，3個線程

  int *workingnum = (int *) malloc(sizeof(int) * 10);
  int i;
  for(i = 0; i < 10; ++i) {
    workingnum[i] = i;
    pool_add_worker(myprocess, &workingnum[i]);   //主線程負(fù)責(zé)添加工作，10個工作
  }

  sleep (5);
  pool_destroy();   //銷毀線程池
  free (workingnum);

  return 0;
}