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#include <assert.h>
#include <emscripten/console.h>
#include <emscripten/emscripten.h>
#include <emscripten/heap.h>
#include <emscripten/proxying.h>
#include <pthread.h>
#include <sched.h>
#include <stdbool.h>
#include <unistd.h>
#if __has_feature(leak_sanitizer) || __has_feature(address_sanitizer)
#define SANITIZER
#endif
// Proxying queues accessed from the worker thread.
em_proxying_queue* queues[2];
#ifndef SANITIZER
// If we are not using sanitizers (which need to use their own allocators),
// override free so we can track when queues are actually freed.
_Atomic int frees = 0;
void __attribute__((noinline)) free(void* ptr) {
frees++;
emscripten_builtin_free(ptr);
}
#endif // SANITIZER
_Atomic int should_execute = 0;
_Atomic int executed[2] = {};
_Atomic int processed = 0;
EMSCRIPTEN_KEEPALIVE
void register_processed(void) {
processed++;
}
void set_flag(void* arg) { *(_Atomic int*)arg = 1; }
// Delay setting the flag until the next turn of the event loop so it can be set
// after the proxying queue is destroyed.
void task(void* arg) { emscripten_async_call(set_flag, arg, 0); }
void* execute_and_free_queue(void* arg) {
// Wait until we are signaled to execute the queue.
while (!should_execute) {
sched_yield();
}
// Execute the proxied work then free the empty queues.
for (int i = 0; i < 2; i++) {
emscripten_proxy_execute_queue(queues[i]);
em_proxying_queue_destroy(queues[i]);
}
// Exit with a live runtime so the queued work notification is received and we
// try to execute the queue again, even though we already executed all its
// work and we are now just waiting for the notifications to be received so we
// can free it.
emscripten_exit_with_live_runtime();
}
void nop(void* arg) {}
int main() {
emscripten_console_log("start");
for (int i = 0; i < 2; i++) {
queues[i] = em_proxying_queue_create();
assert(queues[i]);
}
// Create the worker and send it tasks.
pthread_t worker;
pthread_create(&worker, NULL, execute_and_free_queue, NULL);
for (int i = 0; i < 2; i++) {
emscripten_proxy_async(queues[i], worker, task, &executed[i]);
}
should_execute = 1;
// Wait for the tasks to be executed. The queues will have been destroyed
// after this.
while (!executed[0] || !executed[1]) {
sched_yield();
}
#ifndef SANITIZER
// Our zombies should not have been freed yet.
int frees_before_cull = frees;
#endif // SANITIZER
// Cull the zombies! (by forcing a new task queue to be allocated)
em_proxying_queue* culler = em_proxying_queue_create();
emscripten_proxy_async(culler, pthread_self(), nop, NULL);
#ifndef SANITIZER
// Now they should be free.
int frees_after_cull = frees;
assert(frees_after_cull > frees_before_cull);
#endif // SANITIZER
// If we try again, there should be nothing left to cull.
em_proxying_queue* non_culler = em_proxying_queue_create();
emscripten_proxy_async(non_culler, pthread_self(), nop, NULL);
#ifndef SANITIZER
assert(frees == frees_after_cull);
#endif
em_proxying_queue_destroy(culler);
em_proxying_queue_destroy(non_culler);
emscripten_console_log("done");
}
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