spa: save the old change_mask and restore when emitting full

When we add a new listener to an object, it will emit the full state
of the object. For this it temporarily sets the change_mask to all
changes. Restore the previous state after this or else we might not
emit the right change_mask for the next listener.

Consider the case where one there are two listeners on an object.
The object emits a change and the first listener wants to enumerate the
changed params. For this is adds a new listener and then triggers the
enumeration. If we set the change_mask to 0 after adding the listener,
the second listener would get a 0 change_mask and fail to update
its state.
This commit is contained in:
Wim Taymans 2021-05-25 15:22:13 +02:00
parent c8c0a152b7
commit 46ef88e520
42 changed files with 151 additions and 77 deletions

View file

@ -141,13 +141,15 @@ static int impl_add_listener(void *object,
{
struct data *d = object;
struct spa_hook_list save;
uint64_t old;
spa_hook_list_isolate(&d->hooks, &save, listener, events, data);
old = d->info.change_mask;
d->info.change_mask = SPA_PORT_CHANGE_MASK_FLAGS |
SPA_PORT_CHANGE_MASK_PARAMS;
spa_node_emit_port_info(&d->hooks, SPA_DIRECTION_INPUT, 0, &d->info);
d->info.change_mask = 0;
d->info.change_mask = old;
spa_hook_list_join(&d->hooks, &save);
@ -526,7 +528,7 @@ int main(int argc, char *argv[])
data.info = SPA_PORT_INFO_INIT();
data.info.change_mask = SPA_PORT_CHANGE_MASK_FLAGS;
data.info.flags = 0;
data.info.change_mask = SPA_PORT_CHANGE_MASK_PARAMS;
data.info.change_mask |= SPA_PORT_CHANGE_MASK_PARAMS;
data.params[0] = SPA_PARAM_INFO(SPA_PARAM_EnumFormat, SPA_PARAM_INFO_READ);
data.params[1] = SPA_PARAM_INFO(SPA_PARAM_Meta, SPA_PARAM_INFO_READ);
data.params[2] = SPA_PARAM_INFO(SPA_PARAM_IO, SPA_PARAM_INFO_READ);