qfedu-linux-advanced-level/day7/rwlock_2.c

#include <stdio.h>
#include <pthread.h>
#include <unistd.h>
#include <string.h>

pthread_rwlock_t rwlock = PTHREAD_RWLOCK_INITIALIZER;
int money = 1000;  // 存款余额
int exit_flag = 0; // 退出标志

void *task1(void *data)
{
    while (1)
    {
        pthread_rwlock_wrlock(&rwlock); // 加写锁
        // 查询余额
        printf("存款任务-余额: %d\n", money);
        usleep(200 * 1000);
        // 从键盘读取存入的金额
        printf("请输入存款金额 (输入 0 结束存款): ");
        fflush(stdout);
        int m;
        scanf("%d", &m);
        if (m == 0)
        {
            exit_flag = 1;
            pthread_rwlock_unlock(&rwlock); // 解锁
            break;
        }
        money += m;
        // 修改余额并打印结果
        printf("存款成功, 余额为 %d\n", money);
        pthread_rwlock_unlock(&rwlock); // 解锁
    }
    pthread_exit(NULL);
}

void *task2(void *data)
{
    while (1)
    {
        pthread_rwlock_wrlock(&rwlock); // 加写锁
        // 查询余额
        printf("取款任务-余额: %d\n", money);
        usleep(200 * 1000);
        // 从键盘读取取出的金额
        printf("请输入取款金额 (输入 0 结束取款): ");
        fflush(stdout);
        int m;
        scanf("%d", &m);
        if (m == 0)
        {
            exit_flag = 1;
            pthread_rwlock_unlock(&rwlock); // 解锁
            break;
        }
        if (money >= m)
        {
            money -= m;
            // 修改余额并打印结果
            printf("取款成功, 余额为 %d\n", money);
        }
        else
        {
            printf("取款失败, 余额不足\n");
        }
        pthread_rwlock_unlock(&rwlock); // 解锁
    }
    pthread_exit(NULL);
}

int main(int argc, char const *argv[])
{
    while (1)
    {
        pthread_t t1, t2;
        pthread_create(&t1, NULL, task1, NULL);
        pthread_create(&t2, NULL, task2, NULL);

        while (1)
        {
            pthread_rwlock_rdlock(&rwlock);
            if (exit_flag)
            {
                pthread_rwlock_unlock(&rwlock);
                break;
            }
            pthread_rwlock_unlock(&rwlock);
        }

        pthread_join(t1, NULL);
        pthread_join(t2, NULL);
    }

    pthread_rwlock_destroy(&rwlock);

    return 0;
}