#include <stdio.h>
#include <threads.h>
#include <stdlib.h>
// 示例1: 简单的线程函数
int simple_thread(void *arg) {
int *id = (int*)arg;
printf("线程 %d 正在运行\n", *id);
return 0;
}
// 示例2: 带互斥锁的线程函数
mtx_t mutex;
int shared_counter = 0;
int counter_thread(void *arg) {
int *iterations = (int*)arg;
for (int i = 0; i < *iterations; ++i) {
mtx_lock(&mutex);
shared_counter++;
mtx_unlock(&mutex);
}
return 0;
}
// 示例3: 使用条件变量
cnd_t condition;
mtx_t condition_mutex;
int data_ready = 0;
int producer_thread(void *arg) {
int *value = (int*)arg;
mtx_lock(&condition_mutex);
printf("生产者: 生成数据 %d\n", *value);
data_ready = 1;
cnd_signal(&condition);
mtx_unlock(&condition_mutex);
return 0;
}
int consumer_thread(void *arg) {
(void)arg; // 未使用参数
mtx_lock(&condition_mutex);
while (!data_ready) {
printf("消费者: 等待数据...\n");
cnd_wait(&condition, &condition_mutex);
}
printf("消费者: 接收到数据\n");
mtx_unlock(&condition_mutex);
return 0;
}
// 示例函数: 演示线程创建和使用
int main(void) {
thrd_t threads[3];
int ids[3] = {1, 2, 3};
printf("=== 简单线程示例 ===\n");
for (int i = 0; i < 3; i++) {
thrd_create(&threads[i], simple_thread, &ids[i]);
}
for (int i = 0; i < 3; i++) {
thrd_join(threads[i], NULL);
}
printf("\n=== 互斥锁示例 ===\n");
mtx_init(&mutex, mtx_plain);
int iterations = 100000;
thrd_t t1, t2;
thrd_create(&t1, counter_thread, &iterations);
thrd_create(&t2, counter_thread, &iterations);
thrd_join(t1, NULL);
thrd_join(t2, NULL);
printf("最终计数器值: %d (应为: %d)\n", shared_counter, 2 * iterations);
mtx_destroy(&mutex);
printf("\n=== 条件变量示例 ===\n");
mtx_init(&condition_mutex, mtx_plain);
cnd_init(&condition);
int value = 42;
thrd_t producer, consumer;
thrd_create(&consumer, consumer_thread, NULL);
thrd_sleep(&(struct timespec){.tv_sec=1}, NULL); // 让消费者先启动
thrd_create(&producer, producer_thread, &value);
thrd_join(producer, NULL);
thrd_join(consumer, NULL);
mtx_destroy(&condition_mutex);
cnd_destroy(&condition);
return 0;
}