HG examples: Possible data races

[ryancaicse]

Hi, should thread-shared static variable hg_progress_shutdown_flag be protected by locks?

mercury/Examples/src/example_rpc_engine.c

Lines 50 to 63 in ce847b7

	hg_engine_finalize(void)
	{
	int ret;
	/* tell progress thread to wrap things up */
	hg_progress_shutdown_flag = 1;
	/* wait for it to shutdown cleanly */
	ret = pthread_join(hg_progress_tid, NULL);
	assert(ret == 0);
	(void) ret;
	return;
	}

mercury/Examples/src/example_rpc_engine.c

Lines 66 to 84 in ce847b7

	static void *
	hg_progress_fn(void *foo)
	{
	hg_return_t ret;
	unsigned int actual_count;
	(void) foo;
	while (!hg_progress_shutdown_flag) {
	do {
	ret = HG_Trigger(hg_context, 0, 1, &actual_count);
	} while (
	(ret == HG_SUCCESS) && actual_count && !hg_progress_shutdown_flag);
	if (!hg_progress_shutdown_flag)
	HG_Progress(hg_context, 100);
	}
	return (NULL);
	}

[soumagne]

Yes you're right sorry, that's been low-priority for me on my list but that should be fixed to either use an atomic variable or use a lock.