X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=threads.cc;h=e0cb277563bb057c989be29379866ac8f090094b;hb=8c8e990efa97568549542133e13d9f4df375dd15;hp=4c7ac41f1849d2a18fa6ad4510df118f2d81f87d;hpb=a9aac0d43e0e24354af4163cd3161036586f029a;p=model-checker.git

diff --git a/threads.cc b/threads.cc
index 4c7ac41..e0cb277 100644
--- a/threads.cc
+++ b/threads.cc
@@ -12,12 +12,12 @@
 
 static void * stack_allocate(size_t size)
 {
-	return malloc(size);
+	return userMalloc(size);
 }
 
 static void stack_free(void *stack)
 {
-	free(stack);
+	userFree(stack);
 }
 
 Thread * thread_current(void)
@@ -33,31 +33,43 @@ int Thread::create_context()
 	if (ret)
 		return ret;
 
-	/* start_routine == NULL means this is our initial context */
-	if (!start_routine)
-		return 0;
-
 	/* Initialize new managed context */
 	stack = stack_allocate(STACK_SIZE);
 	context.uc_stack.ss_sp = stack;
 	context.uc_stack.ss_size = STACK_SIZE;
 	context.uc_stack.ss_flags = 0;
-	context.uc_link = &model->system_thread->context;
+	context.uc_link = model->get_system_context();
 	makecontext(&context, start_routine, 1, arg);
 
 	return 0;
 }
 
-int Thread::swap(Thread *t)
+int Thread::swap(Thread *t, ucontext_t *ctxt)
 {
-	return swapcontext(&this->context, &t->context);
+	return swapcontext(&t->context, ctxt);
 }
 
-void Thread::dispose()
+int Thread::swap(ucontext_t *ctxt, Thread *t)
 {
-	DEBUG("completed thread %d\n", thread_current()->get_id());
-	state = THREAD_COMPLETED;
-	stack_free(stack);
+	return swapcontext(ctxt, &t->context);
+}
+
+void Thread::complete()
+{
+	if (state != THREAD_COMPLETED) {
+		DEBUG("completed thread %d\n", get_id());
+		state = THREAD_COMPLETED;
+		if (stack)
+			stack_free(stack);
+	}
+}
+
+void * Thread::operator new(size_t size) {
+	return userMalloc(size);
+}
+
+void Thread::operator delete(void *ptr) {
+	userFree(ptr);
 }
 
 Thread::Thread(thrd_t *t, void (*func)(), void *a) {
@@ -75,20 +87,12 @@ Thread::Thread(thrd_t *t, void (*func)(), void *a) {
 	state = THREAD_CREATED;
 	id = model->get_next_id();
 	*user_thread = id;
-	model->scheduler->add_thread(this);
 }
 
-Thread::Thread(thrd_t *t) {
-	/* system thread */
-	user_thread = t;
-	start_routine = NULL;
-	arg = NULL;
-
-	state = THREAD_CREATED;
-	id = model->get_next_id();
-	*user_thread = id;
-	create_context();
-	model->add_system_thread(this);
+Thread::~Thread()
+{
+	complete();
+	model->remove_thread(this);
 }
 
 thread_id_t Thread::get_id()
@@ -104,13 +108,13 @@ static int thread_system_next(void)
 	Thread *curr, *next;
 
 	curr = thread_current();
-	model->check_current_action();
 	if (curr) {
-		if (curr->get_state() == THREAD_READY)
+		if (curr->get_state() == THREAD_READY) {
+			model->check_current_action();
 			model->scheduler->add_thread(curr);
-		else if (curr->get_state() == THREAD_RUNNING)
+		} else if (curr->get_state() == THREAD_RUNNING)
 			/* Stopped while running; i.e., completed */
-			curr->dispose();
+			curr->complete();
 		else
 			DEBUG("ERROR: current thread in unexpected state??\n");
 	}
@@ -120,7 +124,7 @@ static int thread_system_next(void)
 	DEBUG("(%d, %d)\n", curr ? curr->get_id() : -1, next ? next->get_id() : -1);
 	if (!next)
 		return 1;
-	return model->system_thread->swap(next);
+	return Thread::swap(model->get_system_context(), next);
 }
 
 static void thread_wait_finish(void)
@@ -136,24 +140,24 @@ static void thread_wait_finish(void)
  */
 int main()
 {
-	thrd_t user_thread, main_thread;
-	Thread *th;
+	thrd_t user_thread;
+	ucontext_t main_context;
 
 	model = new ModelChecker();
 
-	th = new Thread(&main_thread);
+	if (getcontext(&main_context))
+		return 1;
+
+	model->set_system_context(&main_context);
 
 	do {
 		/* Start user program */
-		thrd_create(&user_thread, &user_main, NULL);
+		model->add_thread(new Thread(&user_thread, &user_main, NULL));
 
 		/* Wait for all threads to complete */
 		thread_wait_finish();
-
-		model->print_trace();
 	} while (model->next_execution());
 
-	delete th;
 	delete model;
 
 	DEBUG("Exiting\n");