// Copyright 2015 The Emscripten Authors. All rights reserved.

// Emscripten is available under two separate licenses, the MIT license and the

// University of Illinois/NCSA Open Source License. Both these licenses can be

// found in the LICENSE file.

#include <cassert>

#include <stdio.h>

#include <stdlib.h>

#include <pthread.h>

#include <emscripten.h>

#include <emscripten/threading.h>

#include <emscripten/console.h>

#include <unistd.h>

#define NUM_THREADS 8

int numThreadsToCreateTotal = 50;

pthread_t thread[NUM_THREADS] = {};

volatile int counter = 0; // Shared data

pthread_mutex_t lock;

void sleep(int msecs)

{

// Test two different variants of sleeping to verify

// against bug https://bugzilla.mozilla.org/show_bug.cgi?id=1131757

#ifdef SPINLOCK_TEST

double t0 = emscripten_get_now();

double t1 = t0 + (double)msecs;

while(emscripten_get_now() < t1)

;

#else

usleep(msecs*1000);

#endif

}

void *ThreadMain(void *arg)

{

pthread_mutex_lock(&lock);

int c = counter;

sleep(100); // Create contention on the lock.

++c;

counter = c;

pthread_mutex_unlock(&lock);

pthread_exit(0);

}

void CreateThread(int i, int n)

{

pthread_attr_t attr;

pthread_attr_init(&attr);

pthread_attr_setstacksize(&attr, 4*1024);

int rc = pthread_create(&thread[i], &attr, ThreadMain, 0);

if (rc != 0 || thread[i] == 0)

printf("Failed to create thread!\n");

pthread_attr_destroy(&attr);

}

int threadNum = 0;

EM_BOOL WaitToJoin(double time, void *userData)

{

int threadsRunning = 0;

// Join all threads.

for(int i = 0; i < NUM_THREADS; ++i)

{

if (thread[i])

{

void *status;

int rc = pthread_join(thread[i], &status);

if (rc == 0)

{

thread[i] = 0;

if (threadNum < numThreadsToCreateTotal)

{

CreateThread(i, threadNum++);

++threadsRunning;

}

}

else

++threadsRunning;

}

}

if (!threadsRunning)

{

if (counter == numThreadsToCreateTotal)

emscripten_outf("All threads finished. Counter = %d as expected", counter);

else

emscripten_errf("All threads finished, but counter = %d != %d!", counter, numThreadsToCreateTotal);

assert(counter == 50);

emscripten_force_exit(0);

return EM_FALSE;

}

return EM_TRUE;

}

int main()

{

pthread_mutexattr_t attr;

pthread_mutexattr_init(&attr);

pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE);

pthread_mutex_init(&lock, &attr);

pthread_mutex_lock(&lock);

pthread_mutex_unlock(&lock);

// Create new threads in parallel.

for(int i = 0; i < NUM_THREADS; ++i)

CreateThread(i, threadNum++);

emscripten_set_timeout_loop(WaitToJoin, 100, 0);

return 99;

}