ladybird/Tests/Kernel/pthread-cond-timedwait-example.cpp
2022-04-01 21:24:45 +01:00

77 lines
1.8 KiB
C++

/*
* Copyright (c) 2018-2020, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <cassert>
#include <cstring>
#include <ctime>
#include <errno.h>
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
struct worker_t {
char const* name;
int count;
pthread_t thread;
pthread_mutex_t lock;
pthread_cond_t cond;
long int wait_time;
};
static void* run_worker(void* args)
{
struct timespec time_to_wait = { 0, 0 };
worker_t* worker = (worker_t*)args;
worker->count = 0;
while (worker->count < 25) {
time_to_wait.tv_sec = time(nullptr) + worker->wait_time;
pthread_mutex_lock(&worker->lock);
int rc = pthread_cond_timedwait(&worker->cond, &worker->lock, &time_to_wait);
// Validate return code is always timed out.
assert(rc == -1);
assert(errno == ETIMEDOUT);
worker->count++;
printf("Increase worker[%s] count to [%d]\n", worker->name, worker->count);
pthread_mutex_unlock(&worker->lock);
}
return nullptr;
}
static void init_worker(worker_t* worker, char const* name, long int wait_time)
{
worker->name = name;
worker->wait_time = wait_time;
pthread_attr_t attr;
pthread_attr_init(&attr);
pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE);
pthread_mutex_init(&worker->lock, nullptr);
pthread_cond_init(&worker->cond, nullptr);
pthread_create(&worker->thread, &attr, &run_worker, (void*)worker);
pthread_attr_destroy(&attr);
}
int main()
{
worker_t worker_a;
init_worker(&worker_a, "A", 2L);
worker_t worker_b;
init_worker(&worker_b, "B", 4L);
pthread_join(worker_a.thread, nullptr);
pthread_join(worker_b.thread, nullptr);
return EXIT_SUCCESS;
}