diff options
Diffstat (limited to 'src/pulsecore/core-subscribe.c')
-rw-r--r-- | src/pulsecore/core-subscribe.c | 233 |
1 files changed, 233 insertions, 0 deletions
diff --git a/src/pulsecore/core-subscribe.c b/src/pulsecore/core-subscribe.c new file mode 100644 index 00000000..e865256a --- /dev/null +++ b/src/pulsecore/core-subscribe.c @@ -0,0 +1,233 @@ +/* $Id$ */ + +/*** + This file is part of PulseAudio. + + PulseAudio is free software; you can redistribute it and/or modify + it under the terms of the GNU Lesser General Public License as published + by the Free Software Foundation; either version 2 of the License, + or (at your option) any later version. + + PulseAudio is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with PulseAudio; if not, write to the Free Software + Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 + USA. +***/ + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +#include <stdio.h> +#include <assert.h> + +#include <pulse/xmalloc.h> + +#include <pulsecore/queue.h> +#include <pulsecore/log.h> + +#include "core-subscribe.h" + +/* The subscription subsystem may be used to be notified whenever an + * entity (sink, source, ...) is created or deleted. Modules may + * register a callback function that is called whenever an event + * matching a subscription mask happens. The execution of the callback + * function is postponed to the next main loop iteration, i.e. is not + * called from within the stack frame the entity was created in. */ + +struct pa_subscription { + pa_core *core; + int dead; + void (*callback)(pa_core *c, pa_subscription_event_type_t t, uint32_t index, void *userdata); + void *userdata; + pa_subscription_mask_t mask; + + pa_subscription *prev, *next; +}; + +struct pa_subscription_event { + pa_subscription_event_type_t type; + uint32_t index; +}; + +static void sched_event(pa_core *c); + +/* Allocate a new subscription object for the given subscription mask. Use the specified callback function and user data */ +pa_subscription* pa_subscription_new(pa_core *c, pa_subscription_mask_t m, void (*callback)(pa_core *c, pa_subscription_event_type_t t, uint32_t index, void *userdata), void *userdata) { + pa_subscription *s; + assert(c); + + s = pa_xmalloc(sizeof(pa_subscription)); + s->core = c; + s->dead = 0; + s->callback = callback; + s->userdata = userdata; + s->mask = m; + + if ((s->next = c->subscriptions)) + s->next->prev = s; + s->prev = NULL; + c->subscriptions = s; + return s; +} + +/* Free a subscription object, effectively marking it for deletion */ +void pa_subscription_free(pa_subscription*s) { + assert(s && !s->dead); + s->dead = 1; + sched_event(s->core); +} + +static void free_item(pa_subscription *s) { + assert(s && s->core); + + if (s->prev) + s->prev->next = s->next; + else + s->core->subscriptions = s->next; + + if (s->next) + s->next->prev = s->prev; + + pa_xfree(s); +} + +/* Free all subscription objects */ +void pa_subscription_free_all(pa_core *c) { + pa_subscription_event *e; + assert(c); + + while (c->subscriptions) + free_item(c->subscriptions); + + if (c->subscription_event_queue) { + while ((e = pa_queue_pop(c->subscription_event_queue))) + pa_xfree(e); + + pa_queue_free(c->subscription_event_queue, NULL, NULL); + c->subscription_event_queue = NULL; + } + + if (c->subscription_defer_event) { + c->mainloop->defer_free(c->subscription_defer_event); + c->subscription_defer_event = NULL; + } +} + +#if 0 +static void dump_event(pa_subscription_event*e) { + switch (e->type & PA_SUBSCRIPTION_EVENT_FACILITY_MASK) { + case PA_SUBSCRIPTION_EVENT_SINK: + pa_log(__FILE__": SINK_EVENT"); + break; + case PA_SUBSCRIPTION_EVENT_SOURCE: + pa_log(__FILE__": SOURCE_EVENT"); + break; + case PA_SUBSCRIPTION_EVENT_SINK_INPUT: + pa_log(__FILE__": SINK_INPUT_EVENT"); + break; + case PA_SUBSCRIPTION_EVENT_SOURCE_OUTPUT: + pa_log(__FILE__": SOURCE_OUTPUT_EVENT"); + break; + case PA_SUBSCRIPTION_EVENT_MODULE: + pa_log(__FILE__": MODULE_EVENT"); + break; + case PA_SUBSCRIPTION_EVENT_CLIENT: + pa_log(__FILE__": CLIENT_EVENT"); + break; + default: + pa_log(__FILE__": OTHER"); + break; + } + + switch (e->type & PA_SUBSCRIPTION_EVENT_TYPE_MASK) { + case PA_SUBSCRIPTION_EVENT_NEW: + pa_log(__FILE__": NEW"); + break; + case PA_SUBSCRIPTION_EVENT_CHANGE: + pa_log(__FILE__": CHANGE"); + break; + case PA_SUBSCRIPTION_EVENT_REMOVE: + pa_log(__FILE__": REMOVE"); + break; + default: + pa_log(__FILE__": OTHER"); + break; + } + + pa_log(__FILE__": %u", e->index); +} +#endif + +/* Deferred callback for dispatching subscirption events */ +static void defer_cb(pa_mainloop_api *m, pa_defer_event *de, void *userdata) { + pa_core *c = userdata; + pa_subscription *s; + assert(c && c->subscription_defer_event == de && c->mainloop == m); + + c->mainloop->defer_enable(c->subscription_defer_event, 0); + + /* Dispatch queued events */ + + if (c->subscription_event_queue) { + pa_subscription_event *e; + + while ((e = pa_queue_pop(c->subscription_event_queue))) { + + for (s = c->subscriptions; s; s = s->next) { + + if (!s->dead && pa_subscription_match_flags(s->mask, e->type)) + s->callback(c, e->type, e->index, s->userdata); + } + + pa_xfree(e); + } + } + + /* Remove dead subscriptions */ + + s = c->subscriptions; + while (s) { + pa_subscription *n = s->next; + if (s->dead) + free_item(s); + s = n; + } +} + +/* Schedule an mainloop event so that a pending subscription event is dispatched */ +static void sched_event(pa_core *c) { + assert(c); + + if (!c->subscription_defer_event) { + c->subscription_defer_event = c->mainloop->defer_new(c->mainloop, defer_cb, c); + assert(c->subscription_defer_event); + } + + c->mainloop->defer_enable(c->subscription_defer_event, 1); +} + +/* Append a new subscription event to the subscription event queue and schedule a main loop event */ +void pa_subscription_post(pa_core *c, pa_subscription_event_type_t t, uint32_t index) { + pa_subscription_event *e; + assert(c); + + e = pa_xmalloc(sizeof(pa_subscription_event)); + e->type = t; + e->index = index; + + if (!c->subscription_event_queue) { + c->subscription_event_queue = pa_queue_new(); + assert(c->subscription_event_queue); + } + + pa_queue_push(c->subscription_event_queue, e); + sched_event(c); +} + + |