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#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>
#include <assert.h>
#include "bounded-queue.h"
struct int_entry {
struct queue_entry link;
int val;
};
struct test_state {
struct bounded_queue *q;
pthread_mutex_t mutex;
pthread_cond_t cond;
int successful_pushes;
int failed_pushes;
int successful_pops;
int failed_pops;
};
static void *push_thread (void *arg) {
struct test_state *state = arg;
struct int_entry *e = malloc (sizeof (*e));
int rc;
e->val = 42;
rc = bounded_queue_push (state->q, &e->link);
pthread_mutex_lock (&state->mutex);
if (!rc) {
state->successful_pushes++;
} else {
free (e);
state->failed_pushes++;
}
pthread_mutex_unlock (&state->mutex);
pthread_cond_signal (&state->cond);
return NULL;
}
static void *pop_thread (void *arg) {
struct test_state *state = arg;
struct int_entry *e;
e = (struct int_entry *)bounded_queue_pop (state->q);
pthread_mutex_lock (&state->mutex);
if (e) {
assert (e->val == 42);
state->successful_pops++;
free (e);
} else {
state->failed_pops++;
}
pthread_mutex_unlock (&state->mutex);
pthread_cond_signal (&state->cond);
return NULL;
}
int main (void) {
struct bounded_queue q;
struct int_entry *e;
struct test_state state;
int i, rc;
rc = bounded_queue_init (&q, 10);
for (i = 0; i < 10; ++i) {
e = malloc (sizeof (*e));
e->val = i;
rc = bounded_queue_push (&q, &e->link);
assert (rc == 0);
}
for (i = 0; i < 10; ++i) {
e = (struct int_entry *)bounded_queue_pop (&q);
assert (e);
assert (e->val == i);
free (e);
}
puts ("Single-threaded test passed.");
memset (&state, 0, sizeof (state));
pthread_mutex_init (&state.mutex, NULL);
pthread_cond_init (&state.cond, NULL);
state.q = &q;
puts ("Starting 20 pusher threads.");
for (i = 0; i < 20; ++i) {
pthread_t t;
pthread_create (&t, NULL, push_thread, (void *)&state);
pthread_detach (t);
}
// Since queue limit is 10, 10 and only 10 pushers should succeed.
puts ("Waiting for winners...");
pthread_mutex_lock (&state.mutex);
while (state.successful_pushes < 10) {
pthread_cond_wait (&state.cond, &state.mutex);
}
pthread_mutex_unlock (&state.mutex);
sleep (1);
pthread_mutex_lock (&state.mutex);
assert (state.successful_pushes == 10);
assert (state.failed_pushes == 0);
pthread_mutex_unlock (&state.mutex);
// Kill the queue: all 10 blocked pushers should fail.
bounded_queue_kill (&q);
puts ("Waiting for losers...");
pthread_mutex_lock (&state.mutex);
while (state.failed_pushes != 10) {
pthread_cond_wait (&state.cond, &state.mutex);
}
pthread_mutex_unlock (&state.mutex);
pthread_mutex_lock (&state.mutex);
assert (state.successful_pushes == 10);
assert (state.failed_pushes == 10);
pthread_mutex_unlock (&state.mutex);
q.killed = 0;
puts ("Starting 20 popper threads...");
for (i = 0; i < 20; ++i) {
pthread_t t;
pthread_create (&t, NULL, pop_thread, (void *)&state);
pthread_detach (t);
}
// We have 10 entries on the queue, so 10 pops should succeed.
puts ("Waiting for winners...");
pthread_mutex_lock (&state.mutex);
while (state.successful_pops != 10) {
pthread_cond_wait (&state.cond, &state.mutex);
}
pthread_mutex_unlock (&state.mutex);
sleep (1);
pthread_mutex_lock (&state.mutex);
assert (state.successful_pops == 10);
assert (state.failed_pops == 0);
pthread_mutex_unlock (&state.mutex);
bounded_queue_kill (&q);
puts ("Waiting for losers...");
pthread_mutex_lock (&state.mutex);
while (state.failed_pops != 10) {
pthread_cond_wait (&state.cond, &state.mutex);
}
pthread_mutex_unlock (&state.mutex);
sleep (1);
pthread_mutex_lock (&state.mutex);
assert (state.successful_pops == 10);
assert (state.failed_pops == 10);
pthread_mutex_unlock (&state.mutex);
puts ("Multi-threaded tests passed.");
pthread_cond_destroy (&state.cond);
pthread_mutex_destroy (&state.mutex);
return 0;
}
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