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// Copyright 2018 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 <pthread.h>
#include <emscripten.h>
#include <emscripten/threading.h>
#include <math.h>
#include <stdio.h>
volatile int threadStarted = 0;
volatile int timeReceived = 0;
volatile double mainThreadTime;
void wait(volatile int *address)
{
int state = emscripten_atomic_load_u32((void*)address);
while(state == 0)
state = emscripten_atomic_load_u32((void*)address);
}
void wake(volatile int *address)
{
emscripten_atomic_store_u32((void*)address, 1);
}
void *thread_main(void *arg)
{
wake(&threadStarted);
wait(&timeReceived);
double pthreadTime = emscripten_get_now();
double timeDifference = pthreadTime - mainThreadTime;
printf("Time difference between pthread and main thread is %f msecs.\n", timeDifference);
#ifdef REPORT_RESULT
REPORT_RESULT(fabs(timeDifference) < 200); // The time difference here should be well less than 1 msec, but test against 200msecs to be super-sure.
#endif
return 0;
}
void busy_sleep(double msecs)
{
double end = emscripten_get_now() + msecs;
while(emscripten_get_now() < end)
;
}
int main()
{
// Cause a one second delay between main() and pthread start that might have a chance to drift the wallclocks on emscripten_get_now().
busy_sleep(1000);
pthread_t thread;
pthread_create(&thread, NULL, thread_main, NULL);
wait(&threadStarted);
mainThreadTime = emscripten_get_now();
wake(&timeReceived);
emscripten_exit_with_live_runtime();
}
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