player: some further cleanup of the mp_cancel crap

Alway give each demuxer its own mp_cancel instance. This makes
management of the mp_cancel things much easier. Also, instead of having
add/remove functions for mp_cancel slaves, replace them with a simpler
to use set_parent function. Remove cancel_and_free_demuxer(), which had
mpctx as parameter only to check an assumption. With this commit,
demuxers have their own mp_cancel, so add demux_cancel_and_free() which
makes use of it.

1 files changed, 6 insertions, 8 deletions

diff --git a/misc/thread_tools.h b/misc/thread_tools.h
index 2198181e6c..89d84ce0b6 100644
--- a/misc/thread_tools.h
+++ b/misc/thread_tools.h
@@ -67,14 +67,12 @@ void mp_cancel_reset(struct mp_cancel *c);
 // There is only one callback. Create a slave mp_cancel to get a private one.
 void mp_cancel_set_cb(struct mp_cancel *c, void (*cb)(void *ctx), void *ctx);
 
-// If c gets triggered, automatically trigger slave. Trying to add a slave more
-// than once or to multiple parents is undefined behavior.
-// The parent mp_cancel must remain valid until the slave is manually removed
-// or destroyed. Destroying a mp_cancel that still has slaves is an error.
-void mp_cancel_add_slave(struct mp_cancel *c, struct mp_cancel *slave);
-
-// Undo mp_cancel_add_slave(). Ignores never added slaves for easier cleanup.
-void mp_cancel_remove_slave(struct mp_cancel *c, struct mp_cancel *slave);
+// If parent gets triggered, automatically trigger slave. There is only 1
+// parent; setting NULL clears the parent. Freeing slave also automatically
+// ends the parent link, but the parent mp_cancel must remain valid until the
+// slave is manually removed or destroyed. Destroying a mp_cancel that still
+// has slaves is an error.
+void mp_cancel_set_parent(struct mp_cancel *slave, struct mp_cancel *parent);
 
 // win32 "Event" HANDLE that indicates the current mp_cancel state.
 void *mp_cancel_get_event(struct mp_cancel *c);