threads: move circular wait check into Threads::is_waiting_on

[c11tester.git] / threads.cc

diff --git a/threads.cc b/threads.cc
index 00e5c2fbd4a0f1287ac6b68b8be50a1a49b82bd8..e4b46561a0e7be13016661a541f09146b9726f28 100644 (file)
--- a/threads.cc
+++ b/threads.cc
@@ -199,7 +199,7 @@ void Thread::set_state(thread_state s)
 }
 
 /**
- * Get the Thread that this Thread is waiting on
+ * Get the Thread that this Thread is immediately waiting on
  * @return The thread we are waiting on, if any; otherwise NULL
  */
 Thread * Thread::waiting_on() const
@@ -213,3 +213,19 @@ Thread * Thread::waiting_on() const
                return (Thread *)pending->get_mutex()->get_state()->locked;
        return NULL;
 }
+
+/**
+ * Check if this Thread is waiting (blocking) on a given Thread, directly or
+ * indirectly (via a chain of waiting threads)
+ *
+ * @param t The Thread on which we may be waiting
+ * @return True if we are waiting on Thread t; false otherwise
+ */
+bool Thread::is_waiting_on(const Thread *t) const
+{
+       Thread *wait;
+       for (wait = waiting_on(); wait != NULL; wait = wait->waiting_on())
+               if (wait == t)
+                       return true;
+       return false;
+}