3 #include "libthreads.h"
8 /* global "model" object */
11 #define STACK_SIZE (1024 * 1024)
13 static void *stack_allocate(size_t size)
18 static void stack_free(void *stack)
23 Thread *thread_current(void)
25 return model->scheduler->get_current_thread();
28 int Thread::create_context()
32 ret = getcontext(&context);
36 /* start_routine == NULL means this is our initial context */
40 /* Initialize new managed context */
41 stack = stack_allocate(STACK_SIZE);
42 context.uc_stack.ss_sp = stack;
43 context.uc_stack.ss_size = STACK_SIZE;
44 context.uc_stack.ss_flags = 0;
45 context.uc_link = &model->system_thread->context;
46 makecontext(&context, start_routine, 1, arg);
51 int Thread::swap(Thread *t)
53 return swapcontext(&this->context, &t->context);
56 void Thread::dispose()
58 DEBUG("completed thread %d\n", thread_current()->get_id());
59 state = THREAD_COMPLETED;
63 Thread::Thread(thrd_t *t, void (*func)(), void *a) {
70 /* Initialize state */
71 ret = create_context();
73 printf("Error in create_context\n");
75 state = THREAD_CREATED;
76 model->assign_id(this);
77 model->scheduler->add_thread(this);
80 Thread::Thread(thrd_t *t) {
83 state = THREAD_CREATED;
84 model->assign_id(this);
86 model->add_system_thread(this);
89 thread_id_t Thread::get_id()
91 return thrd_to_id(*user_thread);
95 * Return 1 if found next thread, 0 otherwise
97 static int thread_system_next(void)
101 curr = thread_current();
102 model->check_current_action();
104 if (curr->get_state() == THREAD_READY)
105 model->scheduler->add_thread(curr);
106 else if (curr->get_state() == THREAD_RUNNING)
107 /* Stopped while running; i.e., completed */
110 DEBUG("ERROR: current thread in unexpected state??\n");
112 next = model->scheduler->next_thread();
114 next->set_state(THREAD_RUNNING);
115 DEBUG("(%d, %d)\n", curr ? curr->get_id() : -1, next ? next->get_id() : -1);
118 return model->system_thread->swap(next);
121 static void thread_wait_finish(void)
126 while (!thread_system_next());
130 * Main system function
134 thrd_t user_thread, main_thread;
137 model = new ModelChecker();
139 th = new Thread(&main_thread);
141 /* Start user program */
142 thrd_create(&user_thread, &user_main, NULL);
144 /* Wait for all threads to complete */
145 thread_wait_finish();
147 model->print_trace();