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#include <assert.h>
#include <stdlib.h>
#include <stdio.h>
#include <pthread.h>
#include "queue.h"
const size_t MAX_QUEUE_SIZE = 100000;
const size_t NUM_PUSH_THREADS = 8;
const size_t NUM_POP_THREADS = 8;
queue_t *queue;
size_t num_seen;
pthread_mutex_t num_seen_mutex;
void *enqueue_worker(void *arg) {
size_t thread_id = *(size_t *) arg;
free(arg);
for (size_t i = thread_id; i < MAX_QUEUE_SIZE; i += NUM_PUSH_THREADS) {
size_t *value = malloc(sizeof(size_t));
assert(value != NULL);
*value = i;
queue_enqueue(queue, value);
}
return NULL;
}
void *dequeue_worker(void *_arg) {
(void) _arg;
for (size_t i = 0; i < MAX_QUEUE_SIZE; i++) {
pthread_mutex_lock(&num_seen_mutex);
if (num_seen == MAX_QUEUE_SIZE) {
pthread_mutex_unlock(&num_seen_mutex);
break;
}
num_seen++;
pthread_mutex_unlock(&num_seen_mutex);
size_t *value = queue_dequeue(queue);
printf("%zu\n", *value);
free(value);
}
return NULL;
}
int main() {
queue = queue_init();
num_seen = 0;
int result = pthread_mutex_init(&num_seen_mutex, NULL);
assert(result == 0);
pthread_t enqueue_threads[NUM_PUSH_THREADS];
pthread_t dequeue_threads[NUM_POP_THREADS];
for (size_t i = 0; i < NUM_PUSH_THREADS; i++) {
size_t *thread_id = malloc(sizeof(size_t));
assert(thread_id != NULL);
*thread_id = i;
result = pthread_create(&enqueue_threads[i], NULL, enqueue_worker, thread_id);
assert(result == 0);
}
for (size_t i = 0; i < NUM_POP_THREADS; i++) {
result = pthread_create(&dequeue_threads[i], NULL, dequeue_worker, NULL);
assert(result == 0);
}
for (size_t i = 0; i < NUM_PUSH_THREADS; i++) {
result = pthread_join(enqueue_threads[i], NULL);
assert(result == 0);
}
for (size_t i = 0; i < NUM_POP_THREADS; i++) {
result = pthread_join(dequeue_threads[i], NULL);
assert(result == 0);
}
result = pthread_mutex_destroy(&num_seen_mutex);
assert(result == 0);
queue_free(queue);
}