bridge_after.c

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/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 2007 - 2009, Digium, Inc.
 *
 * Richard Mudgett <[email protected]>
 *
 * 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 After Bridge Execution API
 *
 * \author Richard Mudgett <[email protected]>
 *
 * See Also:
 * \arg \ref AstCREDITS
 */

/*** MODULEINFO
 <support_level>core</support_level>
 ***/

#include "asterisk.h"

#include "asterisk/logger.h"
#include "asterisk/channel.h"
#include "asterisk/pbx.h"
#include "asterisk/bridge_after.h"

struct after_bridge_cb_node {
 /*! Next list node. */
 AST_LIST_ENTRY(after_bridge_cb_node) list;
 /*! Desired callback function. */
 ast_bridge_after_cb callback;
 /*! After bridge callback will not be called and destroy any resources data may contain. */
 ast_bridge_after_cb_failed failed;
 /*! Extra data to pass to the callback. */
 void *data;
 /*! Reason the after bridge callback failed. */
 enum ast_bridge_after_cb_reason reason;
};

struct after_bridge_cb_ds {
 /*! After bridge callbacks container. */
 AST_LIST_HEAD(, after_bridge_cb_node) callbacks;
};

/*!
 * \internal
 * \brief Indicate after bridge callback failed.
 * \since 12.0.0
 *
 * \param node After bridge callback node.
 *
 * \return Nothing
 */
static void after_bridge_cb_failed(struct after_bridge_cb_node *node)
{
 if (node->failed) {
 node->failed(node->reason, node->data);
 node->failed = NULL;
 }
}

/*!
 * \internal
 * \brief Run discarding any after bridge callbacks.
 * \since 12.0.0
 *
 * \param after_bridge After bridge callback container process.
 * \param reason Why are we doing this.
 *
 * \return Nothing
 */
static void after_bridge_cb_run_discard(struct after_bridge_cb_ds *after_bridge, enum ast_bridge_after_cb_reason reason)
{
 struct after_bridge_cb_node *node;

 for (;;) {
 AST_LIST_LOCK(&after_bridge->callbacks);
 node = AST_LIST_REMOVE_HEAD(&after_bridge->callbacks, list);
 AST_LIST_UNLOCK(&after_bridge->callbacks);
 if (!node) {
 break;
 }
 if (!node->reason) {
 node->reason = reason;
 }
 after_bridge_cb_failed(node);
 ast_free(node);
 }
}

/*!
 * \internal
 * \brief Destroy the after bridge callback datastore.
 * \since 12.0.0
 *
 * \param data After bridge callback data to destroy.
 *
 * \return Nothing
 */
static void after_bridge_cb_destroy(void *data)
{
 struct after_bridge_cb_ds *after_bridge = data;

 after_bridge_cb_run_discard(after_bridge, AST_BRIDGE_AFTER_CB_REASON_DESTROY);

 AST_LIST_HEAD_DESTROY(&after_bridge->callbacks);
 ast_free(after_bridge);
}

static struct after_bridge_cb_ds *after_bridge_cb_find(struct ast_channel *chan);

/*!
 * \internal
 * \brief Fixup the after bridge callback datastore.
 * \since 12.0.0
 *
 * \param data After bridge callback data to fixup.
 * \param old_chan The datastore is moving from this channel.
 * \param new_chan The datastore is moving to this channel.
 *
 * \return Nothing
 */
static void after_bridge_cb_fixup(void *data, struct ast_channel *old_chan, struct ast_channel *new_chan)
{
 struct after_bridge_cb_ds *after_bridge;
 struct after_bridge_cb_node *node;

 after_bridge = after_bridge_cb_find(new_chan);
 if (!after_bridge) {
 return;
 }

 AST_LIST_LOCK(&after_bridge->callbacks);
 node = AST_LIST_LAST(&after_bridge->callbacks);
 if (node && !node->reason) {
 node->reason = AST_BRIDGE_AFTER_CB_REASON_MASQUERADE;
 }
 AST_LIST_UNLOCK(&after_bridge->callbacks);
}

static const struct ast_datastore_info after_bridge_cb_info = {
 .type = "after-bridge-cb",
 .destroy = after_bridge_cb_destroy,
 .chan_fixup = after_bridge_cb_fixup,
};

/*!
 * \internal
 * \brief Find an after bridge callback datastore container.
 * \since 12.0.0
 *
 * \param chan Channel to find the after bridge callback container on.
 *
 * \retval after_bridge datastore container on success.
 * \retval NULL on error.
 */
static struct after_bridge_cb_ds *after_bridge_cb_find(struct ast_channel *chan)
{
 struct ast_datastore *datastore;
 SCOPED_CHANNELLOCK(lock, chan);

 datastore = ast_channel_datastore_find(chan, &after_bridge_cb_info, NULL);
 if (!datastore) {
 return NULL;
 }
 return datastore->data;
}

/*!
 * \internal
 * \brief Setup/create an after bridge callback datastore container.
 * \since 12.0.0
 *
 * \param chan Channel to setup/create the after bridge callback container on.
 *
 * \retval after_bridge datastore container on success.
 * \retval NULL on error.
 */
static struct after_bridge_cb_ds *after_bridge_cb_setup(struct ast_channel *chan)
{
 struct ast_datastore *datastore;
 struct after_bridge_cb_ds *after_bridge;
 SCOPED_CHANNELLOCK(lock, chan);

 datastore = ast_channel_datastore_find(chan, &after_bridge_cb_info, NULL);
 if (datastore) {
 return datastore->data;
 }

 /* Create a new datastore. */
 datastore = ast_datastore_alloc(&after_bridge_cb_info, NULL);
 if (!datastore) {
 return NULL;
 }
 after_bridge = ast_calloc(1, sizeof(*after_bridge));
 if (!after_bridge) {
 ast_datastore_free(datastore);
 return NULL;
 }
 AST_LIST_HEAD_INIT(&after_bridge->callbacks);
 datastore->data = after_bridge;
 ast_channel_datastore_add(chan, datastore);

 return datastore->data;
}

void ast_bridge_run_after_callback(struct ast_channel *chan)
{
 struct after_bridge_cb_ds *after_bridge;
 struct after_bridge_cb_node *node;

 after_bridge = after_bridge_cb_find(chan);
 if (!after_bridge) {
 return;
 }

 for (;;) {
 AST_LIST_LOCK(&after_bridge->callbacks);
 node = AST_LIST_REMOVE_HEAD(&after_bridge->callbacks, list);
 AST_LIST_UNLOCK(&after_bridge->callbacks);
 if (!node) {
 break;
 }
 if (node->reason) {
 after_bridge_cb_failed(node);
 } else {
 node->failed = NULL;
 node->callback(chan, node->data);
 }
 ast_free(node);
 }
}

void ast_bridge_discard_after_callback(struct ast_channel *chan, enum ast_bridge_after_cb_reason reason)
{
 struct after_bridge_cb_ds *after_bridge;

 after_bridge = after_bridge_cb_find(chan);
 if (!after_bridge) {
 return;
 }

 after_bridge_cb_run_discard(after_bridge, reason);
}

int ast_bridge_set_after_callback(struct ast_channel *chan, ast_bridge_after_cb callback, ast_bridge_after_cb_failed failed, void *data)
{
 struct after_bridge_cb_ds *after_bridge;
 struct after_bridge_cb_node *new_node;
 struct after_bridge_cb_node *last_node;

 /* Sanity checks. */
 ast_assert(chan != NULL);
 if (!chan || !callback) {
 return -1;
 }

 after_bridge = after_bridge_cb_setup(chan);
 if (!after_bridge) {
 return -1;
 }

 /* Create a new callback node. */
 new_node = ast_calloc(1, sizeof(*new_node));
 if (!new_node) {
 return -1;
 }
 new_node->callback = callback;
 new_node->failed = failed;
 new_node->data = data;

 /* Put it in the container disabling any previously active one. */
 AST_LIST_LOCK(&after_bridge->callbacks);
 last_node = AST_LIST_LAST(&after_bridge->callbacks);
 if (last_node && !last_node->reason) {
 last_node->reason = AST_BRIDGE_AFTER_CB_REASON_REPLACED;
 }
 AST_LIST_INSERT_TAIL(&after_bridge->callbacks, new_node, list);
 AST_LIST_UNLOCK(&after_bridge->callbacks);
 return 0;
}

const char *ast_bridge_after_cb_reason_string(enum ast_bridge_after_cb_reason reason)
{
 switch (reason) {
 case AST_BRIDGE_AFTER_CB_REASON_DESTROY:
 return "Channel destroyed (hungup)";
 case AST_BRIDGE_AFTER_CB_REASON_REPLACED:
 return "Callback was replaced";
 case AST_BRIDGE_AFTER_CB_REASON_MASQUERADE:
 return "Channel masqueraded";
 case AST_BRIDGE_AFTER_CB_REASON_DEPART:
 return "Channel was departed from bridge";
 case AST_BRIDGE_AFTER_CB_REASON_REMOVED:
 return "Callback was removed";
 case AST_BRIDGE_AFTER_CB_REASON_IMPART_FAILED:
 return "Channel failed joining the bridge";
 }
 return "Unknown";
}

struct after_bridge_goto_ds {
 /*! Goto string that can be parsed by ast_parseable_goto(). */
 const char *parseable_goto;
 /*! Specific goto context or default context for parseable_goto. */
 const char *context;
 /*! Specific goto exten or default exten for parseable_goto. */
 const char *exten;
 /*! Specific goto priority or default priority for parseable_goto. */
 int priority;
 /*! TRUE if the peer should run the h exten. */
 unsigned int run_h_exten:1;
 /*! Specific goto location */
 unsigned int specific:1;
};

/*!
 * \internal
 * \brief Destroy the after bridge goto datastore.
 * \since 12.0.0
 *
 * \param data After bridge goto data to destroy.
 *
 * \return Nothing
 */
static void after_bridge_goto_destroy(void *data)
{
 struct after_bridge_goto_ds *after_bridge = data;

 ast_free((char *) after_bridge->parseable_goto);
 ast_free((char *) after_bridge->context);
 ast_free((char *) after_bridge->exten);
 ast_free((char *) after_bridge);
}

/*!
 * \internal
 * \brief Fixup the after bridge goto datastore.
 * \since 12.0.0
 *
 * \param data After bridge goto data to fixup.
 * \param old_chan The datastore is moving from this channel.
 * \param new_chan The datastore is moving to this channel.
 *
 * \return Nothing
 */
static void after_bridge_goto_fixup(void *data, struct ast_channel *old_chan, struct ast_channel *new_chan)
{
 /* There can be only one. Discard any already on the new channel. */
 ast_bridge_discard_after_goto(new_chan);
}

static const struct ast_datastore_info after_bridge_goto_info = {
 .type = "after-bridge-goto",
 .destroy = after_bridge_goto_destroy,
 .chan_fixup = after_bridge_goto_fixup,
};

/*!
 * \internal
 * \brief Remove channel goto location after the bridge and return it.
 * \since 12.0.0
 *
 * \param chan Channel to remove after bridge goto location.
 *
 * \retval datastore on success.
 * \retval NULL on error or not found.
 */
static struct ast_datastore *after_bridge_goto_remove(struct ast_channel *chan)
{
 struct ast_datastore *datastore;

 ast_channel_lock(chan);
 datastore = ast_channel_datastore_find(chan, &after_bridge_goto_info, NULL);
 if (datastore && ast_channel_datastore_remove(chan, datastore)) {
 datastore = NULL;
 }
 ast_channel_unlock(chan);

 return datastore;
}

void ast_bridge_discard_after_goto(struct ast_channel *chan)
{
 struct ast_datastore *datastore;

 datastore = after_bridge_goto_remove(chan);
 if (datastore) {
 ast_datastore_free(datastore);
 }
}

void ast_bridge_read_after_goto(struct ast_channel *chan, char *buffer, size_t buf_size)
{
 struct ast_datastore *datastore;
 struct after_bridge_goto_ds *after_bridge;
 char *current_pos = buffer;
 size_t remaining_size = buf_size;

 SCOPED_CHANNELLOCK(lock, chan);

 datastore = ast_channel_datastore_find(chan, &after_bridge_goto_info, NULL);
 if (!datastore) {
 buffer[0] = '\0';
 return;
 }

 after_bridge = datastore->data;

 if (after_bridge->parseable_goto) {
 snprintf(buffer, buf_size, "%s", after_bridge->parseable_goto);
 return;
 }

 if (!ast_strlen_zero(after_bridge->context)) {
 snprintf(current_pos, remaining_size, "%s,", after_bridge->context);
 remaining_size = remaining_size - strlen(current_pos);
 current_pos += strlen(current_pos);
 }

 if (after_bridge->run_h_exten) {
 snprintf(current_pos, remaining_size, "h,");
 remaining_size = remaining_size - strlen(current_pos);
 current_pos += strlen(current_pos);
 } else if (!ast_strlen_zero(after_bridge->exten)) {
 snprintf(current_pos, remaining_size, "%s,", after_bridge->exten);
 remaining_size = remaining_size - strlen(current_pos);
 current_pos += strlen(current_pos);
 }

 snprintf(current_pos, remaining_size, "%d", after_bridge->priority);
}

int ast_bridge_setup_after_goto(struct ast_channel *chan)
{
 struct ast_datastore *datastore;
 struct after_bridge_goto_ds *after_bridge;
 int goto_failed = -1;

 /* We are going to be leaving the bridging system now;
 * clear any pending unbridge flags
 */
 ast_channel_set_unbridged(chan, 0);

 /* Determine if we are going to setup a dialplan location and where. */
 if (ast_channel_softhangup_internal_flag(chan) & AST_SOFTHANGUP_ASYNCGOTO) {
 /* An async goto has already setup a location. */
 ast_channel_clear_softhangup(chan, AST_SOFTHANGUP_ASYNCGOTO);
 if (!ast_check_hangup(chan)) {
 goto_failed = 0;
 }
 return goto_failed;
 }

 /* Get after bridge goto datastore. */
 datastore = after_bridge_goto_remove(chan);
 if (!datastore) {
 return goto_failed;
 }

 after_bridge = datastore->data;
 if (after_bridge->run_h_exten) {
 if (ast_exists_extension(chan, after_bridge->context, "h", 1,
 S_COR(ast_channel_caller(chan)->id.number.valid,
 ast_channel_caller(chan)->id.number.str, NULL))) {
 ast_debug(1, "Running after bridge goto h exten %s,h,1\n",
 ast_channel_context(chan));
 ast_pbx_h_exten_run(chan, after_bridge->context);
 }
 } else if (!ast_check_hangup(chan)) {
 /* Clear the outgoing flag */
 ast_channel_clear_flag(chan, AST_FLAG_OUTGOING);

 if (after_bridge->specific) {
 goto_failed = ast_explicit_goto(chan, after_bridge->context,
 after_bridge->exten, after_bridge->priority);
 } else if (!ast_strlen_zero(after_bridge->parseable_goto)) {
 char *context;
 char *exten;
 int priority;

 /* Option F(x) for Bridge(), Dial(), and Queue() */

 /* Save current dialplan location in case of failure. */
 context = ast_strdupa(ast_channel_context(chan));
 exten = ast_strdupa(ast_channel_exten(chan));
 priority = ast_channel_priority(chan);

 /* Set current dialplan position to default dialplan position */
 ast_explicit_goto(chan, after_bridge->context, after_bridge->exten,
 after_bridge->priority);

 /* Then perform the goto */
 goto_failed = ast_parseable_goto(chan, after_bridge->parseable_goto);
 if (goto_failed) {
 /* Restore original dialplan location. */
 ast_channel_context_set(chan, context);
 ast_channel_exten_set(chan, exten);
 ast_channel_priority_set(chan, priority);
 }
 } else {
 /* Option F() for Bridge(), Dial(), and Queue() */
 goto_failed = ast_goto_if_exists(chan, after_bridge->context,
 after_bridge->exten, after_bridge->priority + 1);
 }
 if (!goto_failed) {
 if (ast_test_flag(ast_channel_flags(chan), AST_FLAG_IN_AUTOLOOP)) {
 ast_channel_priority_set(chan, ast_channel_priority(chan) + 1);
 }

 ast_debug(1, "Setup after bridge goto location to %s,%s,%d.\n",
 ast_channel_context(chan),
 ast_channel_exten(chan),
 ast_channel_priority(chan));
 }
 }

 /* Discard after bridge goto datastore. */
 ast_datastore_free(datastore);

 return goto_failed;
}

void ast_bridge_run_after_goto(struct ast_channel *chan)
{
 int goto_failed;

 goto_failed = ast_bridge_setup_after_goto(chan);
 if (goto_failed || ast_pbx_run(chan)) {
 ast_hangup(chan);
 }
}

/*!
 * \internal
 * \brief Set after bridge goto location of channel.
 * \since 12.0.0
 *
 * \param chan Channel to setup after bridge goto location.
 * \param run_h_exten TRUE if the h exten should be run.
 * \param specific TRUE if the context/exten/priority is exactly specified.
 * \param context Context to goto after bridge.
 * \param exten Exten to goto after bridge. (Could be NULL if run_h_exten)
 * \param priority Priority to goto after bridge.
 * \param parseable_goto User specified goto string. (Could be NULL)
 *
 * \details Add a channel datastore to setup the goto location
 * when the channel leaves the bridge and run a PBX from there.
 *
 * If run_h_exten then execute the h exten found in the given context.
 * Else if specific then goto the given context/exten/priority.
 * Else if parseable_goto then use the given context/exten/priority
 * as the relative position for the parseable_goto.
 * Else goto the given context/exten/priority+1.
 *
 * \return Nothing
 */
static void __after_bridge_set_goto(struct ast_channel *chan, int run_h_exten, int specific, const char *context, const char *exten, int priority, const char *parseable_goto)
{
 struct ast_datastore *datastore;
 struct after_bridge_goto_ds *after_bridge;

 /* Sanity checks. */
 ast_assert(chan != NULL);
 if (!chan) {
 return;
 }
 if (run_h_exten) {
 ast_assert(run_h_exten && context);
 if (!context) {
 return;
 }
 } else {
 ast_assert(context && exten && 0 < priority);
 if (!context || !exten || priority < 1) {
 return;
 }
 }

 /* Create a new datastore. */
 datastore = ast_datastore_alloc(&after_bridge_goto_info, NULL);
 if (!datastore) {
 return;
 }
 after_bridge = ast_calloc(1, sizeof(*after_bridge));
 if (!after_bridge) {
 ast_datastore_free(datastore);
 return;
 }

 /* Initialize it. */
 after_bridge->parseable_goto = ast_strdup(parseable_goto);
 after_bridge->context = ast_strdup(context);
 after_bridge->exten = ast_strdup(exten);
 after_bridge->priority = priority;
 after_bridge->run_h_exten = run_h_exten ? 1 : 0;
 after_bridge->specific = specific ? 1 : 0;
 datastore->data = after_bridge;
 if ((parseable_goto && !after_bridge->parseable_goto)
 || (context && !after_bridge->context)
 || (exten && !after_bridge->exten)) {
 ast_datastore_free(datastore);
 return;
 }

 /* Put it on the channel replacing any existing one. */
 ast_channel_lock(chan);
 ast_bridge_discard_after_goto(chan);
 ast_channel_datastore_add(chan, datastore);
 ast_channel_unlock(chan);
}

void ast_bridge_set_after_goto(struct ast_channel *chan, const char *context, const char *exten, int priority)
{
 __after_bridge_set_goto(chan, 0, 1, context, exten, priority, NULL);
}

void ast_bridge_set_after_h(struct ast_channel *chan, const char *context)
{
 __after_bridge_set_goto(chan, 1, 0, context, NULL, 1, NULL);
}

void ast_bridge_set_after_go_on(struct ast_channel *chan, const char *context, const char *exten, int priority, const char *parseable_goto)
{
 char *p_goto;

 if (!ast_strlen_zero(parseable_goto)) {
 p_goto = ast_strdupa(parseable_goto);
 ast_replace_subargument_delimiter(p_goto);
 } else {
 p_goto = NULL;
 }
 __after_bridge_set_goto(chan, 0, 0, context, exten, priority, p_goto);
}