X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=libthreads.c;h=2ffe958ed193909cc2960fabcf28c9ee4d3eae4c;hb=dcd84cc88d70497bdc173c4bb78ce30afe4fb5c5;hp=892d784587b7c00fa22083bde526567729326170;hpb=9d5424201af87d2824eb9411f1afa42e82e2f602;p=model-checker.git

diff --git a/libthreads.c b/libthreads.c
index 892d784..2ffe958 100644
--- a/libthreads.c
+++ b/libthreads.c
@@ -5,7 +5,7 @@
 #include "schedule.h"
 #include "common.h"
 
-/* global "model" struct */
+/* global "model" object */
 #include "model.h"
 
 #define STACK_SIZE (1024 * 1024)
@@ -47,56 +47,68 @@ static int create_context(struct thread *t)
 static int create_initial_thread(struct thread *t)
 {
 	memset(t, 0, sizeof(*t));
+	model->assign_id(t);
 	return create_context(t);
 }
 
-static int thread_swap(struct thread *old, struct thread *new)
+static int thread_swap(struct thread *t1, struct thread *t2)
 {
-	return swapcontext(&old->context, &new->context);
-}
-
-int thread_yield(void)
-{
-	struct thread *old, *next;
-
-	DBG();
-	old = thread_current();
-	model->scheduler->add_thread(old);
-	next = model->scheduler->next_thread();
-	DEBUG("(%d, %d)\n", old->index, next->index);
-	return thread_swap(old, next);
+	return swapcontext(&t1->context, &t2->context);
 }
 
 static void thread_dispose(struct thread *t)
 {
-	DEBUG("completed thread %d\n", thread_current()->index);
+	DEBUG("completed thread %d\n", thread_current()->id);
 	t->state = THREAD_COMPLETED;
 	stack_free(t->stack);
 }
 
-static void thread_wait_finish(void)
+/*
+ * Return 1 if found next thread, 0 otherwise
+ */
+static int thread_system_next(void)
 {
 	struct thread *curr, *next;
 
+	curr = thread_current();
+	if (curr) {
+		if (curr->state == THREAD_READY)
+			model->scheduler->add_thread(curr);
+		else if (curr->state == THREAD_RUNNING)
+			/* Stopped while running; i.e., completed */
+			thread_dispose(curr);
+		else
+			DEBUG("ERROR: current thread in unexpected state??\n");
+	}
+	next = model->scheduler->next_thread();
+	if (next)
+		next->state = THREAD_RUNNING;
+	DEBUG("(%d, %d)\n", curr ? curr->id : -1, next ? next->id : -1);
+	if (!next)
+		return 1;
+	return thread_swap(model->system_thread, next);
+}
+
+static void thread_wait_finish(void)
+{
+
 	DBG();
 
-	do {
-		if ((curr = thread_current()))
-			thread_dispose(curr);
-		next = model->scheduler->next_thread();
-	} while (next && !thread_swap(model->system_thread, next));
+	while (!thread_system_next());
 }
 
-int thread_create(struct thread *t, void (*start_routine), void *arg)
+/*
+ * User program API functions
+ */
+int thread_create(struct thread *t, void (*start_routine)(), void *arg)
 {
-	static int created = 1;
 	int ret = 0;
 
 	DBG();
 
 	memset(t, 0, sizeof(*t));
-	t->index = created++;
-	DEBUG("create thread %d\n", t->index);
+	model->assign_id(t);
+	DEBUG("create thread %d\n", t->id);
 
 	t->start_routine = start_routine;
 	t->arg = arg;
@@ -118,21 +130,35 @@ void thread_join(struct thread *t)
 		thread_yield();
 }
 
+int thread_yield(void)
+{
+	struct thread *old, *next;
+
+	DBG();
+	old = thread_current();
+	old->state = THREAD_READY;
+	next = model->system_thread;
+	return thread_swap(old, next);
+}
+
 struct thread *thread_current(void)
 {
 	return model->scheduler->get_current_thread();
 }
 
+/*
+ * Main system function
+ */
 int main()
 {
 	struct thread user_thread;
 	struct thread *main_thread;
 
-	model_checker_init();
+	model = new ModelChecker();
 
-	main_thread = malloc(sizeof(struct thread));
+	main_thread = (struct thread *)malloc(sizeof(*main_thread));
 	create_initial_thread(main_thread);
-	model_checker_add_system_thread(main_thread);
+	model->add_system_thread(main_thread);
 
 	/* Start user program */
 	thread_create(&user_thread, &user_main, NULL);