From a6a358ce619e50ce6ca2307555a010d1c08341e0 Mon Sep 17 00:00:00 2001 From: wm4 Date: Fri, 26 Feb 2016 23:28:02 +0100 Subject: [PATCH] dispatch: clarify lifetime issues --- misc/dispatch.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/misc/dispatch.c b/misc/dispatch.c index 99a78bd006..2ddac2c92d 100644 --- a/misc/dispatch.c +++ b/misc/dispatch.c @@ -62,10 +62,15 @@ static void queue_dtor(void *p) pthread_mutex_destroy(&queue->exclusive_lock); } -// A dispatch queue lets other threads runs callbacks in a target thread. -// The target thread is the thread which created the queue and which calls -// mp_dispatch_queue_process(). -// Free the dispatch queue with talloc_free(). (It must be empty.) +// A dispatch queue lets other threads run callbacks in a target thread. +// The target thread is the thread which calls mp_dispatch_queue_process(). +// Free the dispatch queue with talloc_free(). At the time of destruction, +// the queue must be empty. The easiest way to guarantee this is to +// terminate all potential senders, then call mp_dispatch_run() with a +// function that e.g. makes the target thread exit, then pthread_join() the +// target thread, and finally destroy the queue. Another way is calling +// mp_dispatch_queue_process() after terminating all potential senders, and +// then destroying the queue. struct mp_dispatch_queue *mp_dispatch_create(void *ta_parent) { struct mp_dispatch_queue *queue = talloc_ptrtype(ta_parent, queue);