Break res_stasis into smaller files.

When implementing playback for stasis-http, the monolithicedness of
res_stasis really started to get in my way.

This patch breaks the major components of res_stasis.c into individual
files.

 * res/stasis/app.c - Stasis application tracking
 * res/stasis/control.c - Channel control objects
 * res/stasis/command.c - Channel command object

This refactoring also allows res_stasis applications to be loaded as
independent modules, such as the new res_stasis_answer module.

The bulk of this patch is simply moving code from one file to another,
adjusting names and adding accessors as necessary.

Review: https://reviewboard.asterisk.org/r/2530/


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@388729 65c4cc65-6c06-0410-ace0-fbb531ad65f3

res/stasis/app.c

@@ -0,0 +1,142 @@
+/*
+ * Asterisk -- An open source telephony toolkit.
+ *
+ * Copyright (C) 2013, Digium, Inc.
+ *
+ * David M. Lee, II <dlee@digium.com>
+ *
+ * See http://www.asterisk.org for more information about
+ * the Asterisk project. Please do not directly contact
+ * any of the maintainers of this project for assistance;
+ * the project provides a web site, mailing lists and IRC
+ * channels for your use.
+ *
+ * This program is free software, distributed under the terms of
+ * the GNU General Public License Version 2. See the LICENSE file
+ * at the top of the source tree.
+ */
+
+/*! \file
+ *
+ * \brief Stasis application support.
+ *
+ * \author David M. Lee, II <dlee@digium.com>
+ */
+
+#include "asterisk.h"
+
+ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
+
+#include "app.h"
+
+#include "asterisk/stasis_app.h"
+#include "asterisk/stasis_channels.h"
+
+/*!
+ * \brief Number of buckets for the channels container for app instances.  Remember
+ * to keep it a prime number!
+ */
+#define APP_CHANNELS_BUCKETS 7
+
+struct app {
+	/*! Callback function for this application. */
+	stasis_app_cb handler;
+	/*! Opaque data to hand to callback function. */
+	void *data;
+	/*! List of channel identifiers this app instance is interested in */
+	struct ao2_container *channels;
+	/*! Name of the Stasis application */
+	char name[];
+};
+
+static void app_dtor(void *obj)
+{
+	struct app *app = obj;
+
+	ao2_cleanup(app->data);
+	app->data = NULL;
+	ao2_cleanup(app->channels);
+	app->channels = NULL;
+}
+
+struct app *app_create(const char *name, stasis_app_cb handler, void *data)
+{
+	RAII_VAR(struct app *, app, NULL, ao2_cleanup);
+	size_t size;
+
+	ast_assert(name != NULL);
+	ast_assert(handler != NULL);
+
+	size = sizeof(*app) + strlen(name) + 1;
+	app = ao2_alloc_options(size, app_dtor, AO2_ALLOC_OPT_LOCK_MUTEX);
+
+	if (!app) {
+		return NULL;
+	}
+
+	strncpy(app->name, name, size - sizeof(*app));
+	app->handler = handler;
+	ao2_ref(data, +1);
+	app->data = data;
+
+	app->channels = ast_str_container_alloc(APP_CHANNELS_BUCKETS);
+	if (!app->channels) {
+		return NULL;
+	}
+
+	ao2_ref(app, +1);
+	return app;
+}
+
+int app_add_channel(struct app *app, const struct ast_channel *chan)
+{
+	const char *uniqueid;
+	ast_assert(chan != NULL);
+	ast_assert(app != NULL);
+
+	uniqueid = ast_channel_uniqueid(chan);
+	if (!ast_str_container_add(app->channels, uniqueid)) {
+		return -1;
+	}
+	return 0;
+}
+
+void app_remove_channel(struct app* app, const struct ast_channel *chan)
+{
+	ast_assert(chan != NULL);
+	ast_assert(app != NULL);
+
+	ao2_find(app->channels, ast_channel_uniqueid(chan), OBJ_KEY | OBJ_NODATA | OBJ_UNLINK);
+}
+
+/*!
+ * \brief Send a message to the given application.
+ * \param app App to send the message to.
+ * \param message Message to send.
+ */
+void app_send(struct app *app, struct ast_json *message)
+{
+	app->handler(app->data, app->name, message);
+}
+
+void app_update(struct app *app, stasis_app_cb handler, void *data)
+{
+	SCOPED_AO2LOCK(lock, app);
+
+	app->handler = handler;
+	ao2_cleanup(app->data);
+	ao2_ref(data, +1);
+	app->data = data;
+}
+
+const char *app_name(const struct app *app)
+{
+	return app->name;
+}
+
+int app_is_watching_channel(struct app *app, const char *uniqueid)
+{
+	RAII_VAR(char *, found, NULL, ao2_cleanup);
+	found = ao2_find(app->channels, uniqueid, OBJ_KEY);
+	return found != NULL;
+}