deal with looping due to bogus future value via promise expiration

[model-checker.git] / schedule.cc

diff --git a/schedule.cc b/schedule.cc
index 8f7f1a98d8cc2833c812243cecaa284d375286ad..cbb4957a3e4a3865730679e8e816dfb51f636324 100644 (file)
--- a/schedule.cc
+++ b/schedule.cc
@@ -32,13 +32,36 @@ void Scheduler::remove_thread(Thread *t)
 }
 
 /**
- * Remove one Thread from the scheduler. This implementation performs FIFO.
- * @return The next Thread to run
+ * Prevent a Thread from being scheduled. The sleeping Thread should be
+ * re-awoken via Scheduler::wake.
+ * @param thread The Thread that should sleep
  */
-Thread * Scheduler::next_thread()
+void Scheduler::sleep(Thread *t)
 {
-       Thread *t = model->schedule_next_thread();
+       remove_thread(t);
+       t->set_state(THREAD_BLOCKED);
+}
 
+/**
+ * Wake a Thread up that was previously waiting (see Scheduler::wait)
+ * @param t The Thread to wake up
+ */
+void Scheduler::wake(Thread *t)
+{
+       add_thread(t);
+       t->set_state(THREAD_READY);
+}
+
+/**
+ * Remove one Thread from the scheduler. This implementation defaults to FIFO,
+ * if a thread is not already provided.
+ *
+ * @param t Thread to run, if chosen by an external entity (e.g.,
+ * ModelChecker). May be NULL to indicate no external choice.
+ * @return The next Thread to run
+ */
+Thread * Scheduler::next_thread(Thread *t)
+{
        if (t != NULL) {
                current = t;
                readyList.remove(t);
@@ -67,7 +90,7 @@ Thread * Scheduler::get_current_thread() const
  * Print debugging information about the current state of the scheduler. Only
  * prints something if debugging is enabled.
  */
-void Scheduler::print()
+void Scheduler::print() const
 {
        if (current)
                DEBUG("Current thread: %d\n", current->get_id());
@@ -75,7 +98,7 @@ void Scheduler::print()
                DEBUG("No current thread\n");
        DEBUG("Num. threads in ready list: %zu\n", readyList.size());
 
-       std::list<Thread *, MyAlloc< Thread * > >::iterator it;
+       std::list<Thread *, MyAlloc< Thread * > >::const_iterator it;
        for (it = readyList.begin(); it != readyList.end(); it++)
                DEBUG("In ready list: thread %d\n", (*it)->get_id());
 }