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  • /*
     * Asterisk -- An open source telephony toolkit.
     *
     * Copyright (C) 2013 Digium, Inc.
     *
     * Richard Mudgett <rmudgett@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 Local proxy channel driver.
     *
     * \author Richard Mudgett <rmudgett@digium.com>
     *
     * See Also:
     * \arg \ref AstCREDITS
     */
    
    /*** MODULEINFO
    	<support_level>core</support_level>
     ***/
    
    
    #include "asterisk.h"
    
    ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
    
    /* ------------------------------------------------------------------- */
    
    #include "asterisk/channel.h"
    #include "asterisk/pbx.h"
    #include "asterisk/cli.h"
    #include "asterisk/manager.h"
    #include "asterisk/devicestate.h"
    #include "asterisk/astobj2.h"
    
    #include "asterisk/bridge.h"
    
    #include "asterisk/core_unreal.h"
    #include "asterisk/core_local.h"
    
    #include "asterisk/stasis.h"
    #include "asterisk/stasis_channels.h"
    
    #include "asterisk/stasis_channels.h"
    
    
    /*** DOCUMENTATION
    	<manager name="LocalOptimizeAway" language="en_US">
    		<synopsis>
    			Optimize away a local channel when possible.
    		</synopsis>
    		<syntax>
    			<xi:include xpointer="xpointer(/docs/manager[@name='Login']/syntax/parameter[@name='ActionID'])" />
    			<parameter name="Channel" required="true">
    				<para>The channel name to optimize away.</para>
    			</parameter>
    		</syntax>
    		<description>
    			<para>A local channel created with "/n" will not automatically optimize away.
    			Calling this command on the local channel will clear that flag and allow
    			it to optimize away if it's bridged or when it becomes bridged.</para>
    		</description>
    	</manager>
    
    	<managerEvent language="en_US" name="LocalBridge">
    		<managerEventInstance class="EVENT_FLAG_CALL">
    			<synopsis>Raised when two halves of a Local Channel form a bridge.</synopsis>
    			<syntax>
    
    				<channel_snapshot prefix="LocalOne"/>
    				<channel_snapshot prefix="LocalTwo"/>
    
    				<parameter name="Context">
    					<para>The context in the dialplan that Channel2 starts in.</para>
    				</parameter>
    				<parameter name="Exten">
    					<para>The extension in the dialplan that Channel2 starts in.</para>
    				</parameter>
    				<parameter name="LocalOptimization">
    					<enumlist>
    						<enum name="Yes"/>
    						<enum name="No"/>
    					</enumlist>
    				</parameter>
    			</syntax>
    		</managerEventInstance>
    	</managerEvent>
    
    	<managerEvent language="en_US" name="LocalOptimizationBegin">
    		<managerEventInstance class="EVENT_FLAG_CALL">
    			<synopsis>Raised when two halves of a Local Channel begin to optimize
    			themselves out of the media path.</synopsis>
    			<syntax>
    
    				<channel_snapshot prefix="LocalOne"/>
    				<channel_snapshot prefix="LocalTwo"/>
    
    				<channel_snapshot prefix="Source"/>
    				<parameter name="DestUniqueId">
    					<para>The unique ID of the bridge into which the local channel is optimizing.</para>
    				</parameter>
    				<parameter name="Id">
    					<para>Identification for the optimization operation.</para>
    				</parameter>
    
    			</syntax>
    			<see-also>
    				<ref type="managerEvent">LocalOptimizationEnd</ref>
    				<ref type="manager">LocalOptimizeAway</ref>
    			</see-also>
    		</managerEventInstance>
    	</managerEvent>
    	<managerEvent language="en_US" name="LocalOptimizationEnd">
    		<managerEventInstance class="EVENT_FLAG_CALL">
    			<synopsis>Raised when two halves of a Local Channel have finished optimizing
    			themselves out of the media path.</synopsis>
    			<syntax>
    
    				<channel_snapshot prefix="LocalOne"/>
    				<channel_snapshot prefix="LocalTwo"/>
    
    				<parameter name="Success">
    					<para>Indicates whether the local optimization succeeded.</para>
    				</parameter>
    				<parameter name="Id">
    					<para>Identification for the optimization operation. Matches the <replaceable>Id</replaceable>
    					from a previous <literal>LocalOptimizationBegin</literal></para>
    				</parameter>
    
    			</syntax>
    			<see-also>
    				<ref type="managerEvent">LocalOptimizationBegin</ref>
    				<ref type="manager">LocalOptimizeAway</ref>
    			</see-also>
    		</managerEventInstance>
    	</managerEvent>
    
     ***/
    
    static const char tdesc[] = "Local Proxy Channel Driver";
    
    static struct ao2_container *locals;
    
    
    static struct ast_channel *local_request(const char *type, struct ast_format_cap *cap, const struct ast_assigned_ids *assignedids, const struct ast_channel *requestor, const char *data, int *cause);
    
    static int local_call(struct ast_channel *ast, const char *dest, int timeout);
    static int local_hangup(struct ast_channel *ast);
    static int local_devicestate(const char *data);
    
    static void local_optimization_started_cb(struct ast_unreal_pvt *base, struct ast_channel *source,
    		enum ast_unreal_channel_indicator dest, unsigned int id);
    static void local_optimization_finished_cb(struct ast_unreal_pvt *base, int success, unsigned int id);
    
    
    static struct ast_manager_event_blob *local_message_to_ami(struct stasis_message *msg);
    
    /*!
     * @{ \brief Define local channel message types.
     */
    STASIS_MESSAGE_TYPE_DEFN(ast_local_bridge_type,
    	.to_ami = local_message_to_ami,
    	);
    STASIS_MESSAGE_TYPE_DEFN(ast_local_optimization_begin_type,
    	.to_ami = local_message_to_ami,
    	);
    STASIS_MESSAGE_TYPE_DEFN(ast_local_optimization_end_type,
    	.to_ami = local_message_to_ami,
    	);
    /*! @} */
    
    /*! \brief Callbacks from the unreal core when channel optimization occurs */
    struct ast_unreal_pvt_callbacks local_unreal_callbacks = {
    	.optimization_started = local_optimization_started_cb,
    	.optimization_finished = local_optimization_finished_cb,
    };
    
    
    /* PBX interface structure for channel registration */
    static struct ast_channel_tech local_tech = {
    	.type = "Local",
    	.description = tdesc,
    	.requester = local_request,
    	.send_digit_begin = ast_unreal_digit_begin,
    	.send_digit_end = ast_unreal_digit_end,
    	.call = local_call,
    	.hangup = local_hangup,
    	.answer = ast_unreal_answer,
    	.read = ast_unreal_read,
    	.write = ast_unreal_write,
    	.write_video = ast_unreal_write,
    	.exception = ast_unreal_read,
    	.indicate = ast_unreal_indicate,
    	.fixup = ast_unreal_fixup,
    	.send_html = ast_unreal_sendhtml,
    	.send_text = ast_unreal_sendtext,
    	.devicestate = local_devicestate,
    	.queryoption = ast_unreal_queryoption,
    	.setoption = ast_unreal_setoption,
    };
    
    /*! What to do with the ;2 channel when ast_call() happens. */
    enum local_call_action {
    	/* The ast_call() will run dialplan on the ;2 channel. */
    	LOCAL_CALL_ACTION_DIALPLAN,
    	/* The ast_call() will impart the ;2 channel into a bridge. */
    	LOCAL_CALL_ACTION_BRIDGE,
    	/* The ast_call() will masquerade the ;2 channel into a channel. */
    	LOCAL_CALL_ACTION_MASQUERADE,
    };
    
    /*! Join a bridge on ast_call() parameters. */
    struct local_bridge {
    	/*! Bridge to join. */
    	struct ast_bridge *join;
    	/*! Channel to swap with when joining bridge. */
    	struct ast_channel *swap;
    	/*! Features that are specific to this channel when pushed into the bridge. */
    	struct ast_bridge_features *features;
    };
    
    /*!
     * \brief the local pvt structure for all channels
     *
     * The local channel pvt has two ast_chan objects - the "owner" and the "next channel", the outbound channel
     *
     * ast_chan owner -> local_pvt -> ast_chan chan
     */
    struct local_pvt {
    	/*! Unreal channel driver base class values. */
    	struct ast_unreal_pvt base;
    	/*! Additional action arguments */
    	union {
    		/*! Make ;2 join a bridge on ast_call(). */
    		struct local_bridge bridge;
    		/*! Make ;2 masquerade into this channel on ast_call(). */
    		struct ast_channel *masq;
    	} action;
    	/*! What to do with the ;2 channel on ast_call(). */
    	enum local_call_action type;
    	/*! Context to call */
    	char context[AST_MAX_CONTEXT];
    	/*! Extension to call */
    	char exten[AST_MAX_EXTENSION];
    };
    
    
    void ast_local_lock_all2(struct ast_channel *chan, void **tech_pvt,
    	struct ast_channel **base_chan, struct ast_channel **base_owner)
    
    {
    	struct local_pvt *p = ast_channel_tech_pvt(chan);
    
    
    	*tech_pvt = NULL;
    	*base_chan = NULL;
    	*base_owner = NULL;
    
    		*tech_pvt = ao2_bump(p);
    		ast_unreal_lock_all(&p->base, base_chan, base_owner);
    	}
    }
    
    void ast_local_lock_all(struct ast_channel *chan, struct ast_channel **outchan,
    			struct ast_channel **outowner)
    {
    	void *tech_pvt;
    	ast_local_lock_all2(chan, &tech_pvt, outchan, outowner);
    }
    
    void ast_local_unlock_all2(void *tech_pvt, struct ast_channel *base_chan,
    	struct ast_channel *base_owner)
    {
    	if (base_chan) {
    		ast_channel_unlock(base_chan);
    		ast_channel_unref(base_chan);
    	}
    
    	if (base_owner) {
    		ast_channel_unlock(base_owner);
    		ast_channel_unref(base_owner);
    	}
    
    	if (tech_pvt) {
    		struct local_pvt *p = tech_pvt;
    		ao2_unlock(&p->base);
    		ao2_ref(tech_pvt, -1);
    
    	}
    }
    
    void ast_local_unlock_all(struct ast_channel *chan)
    {
    	struct local_pvt *p = ast_channel_tech_pvt(chan);
    	struct ast_unreal_pvt *base;
    
    	if (!p) {
    		return;
    	}
    
    	base = &p->base;
    
    	ast_local_unlock_all2(p, base->chan, base->owner);
    
    struct ast_channel *ast_local_get_peer(struct ast_channel *ast)
    {
    	struct local_pvt *p = ast_channel_tech_pvt(ast);
    	struct local_pvt *found;
    	struct ast_channel *peer;
    
    	if (!p) {
    		return NULL;
    	}
    
    	found = p ? ao2_find(locals, p, 0) : NULL;
    	if (!found) {
    		/* ast is either not a local channel or it has alredy been hungup */
    		return NULL;
    	}
    	ao2_lock(found);
    	if (ast == p->base.owner) {
    		peer = p->base.chan;
    	} else if (ast == p->base.chan) {
    		peer = p->base.owner;
    	} else {
    		peer = NULL;
    	}
    	if (peer) {
    		ast_channel_ref(peer);
    	}
    	ao2_unlock(found);
    	ao2_ref(found, -1);
    	return peer;
    }
    
    /*! \brief Adds devicestate to local channels */
    static int local_devicestate(const char *data)
    {
    	int is_inuse = 0;
    	int res = AST_DEVICE_INVALID;
    	char *exten = ast_strdupa(data);
    	char *context;
    	char *opts;
    	struct local_pvt *lp;
    	struct ao2_iterator it;
    
    	/* Strip options if they exist */
    	opts = strchr(exten, '/');
    	if (opts) {
    		*opts = '\0';
    	}
    
    	context = strchr(exten, '@');
    	if (!context) {
    		ast_log(LOG_WARNING,
    			"Someone used Local/%s somewhere without a @context. This is bad.\n", data);
    		return AST_DEVICE_INVALID;
    	}
    	*context++ = '\0';
    
    	it = ao2_iterator_init(locals, 0);
    	for (; (lp = ao2_iterator_next(&it)); ao2_ref(lp, -1)) {
    		ao2_lock(lp);
    		if (!strcmp(exten, lp->exten)
    			&& !strcmp(context, lp->context)) {
    			res = AST_DEVICE_NOT_INUSE;
    			if (lp->base.owner
    				&& ast_test_flag(&lp->base, AST_UNREAL_CARETAKER_THREAD)) {
    				is_inuse = 1;
    			}
    		}
    		ao2_unlock(lp);
    		if (is_inuse) {
    			res = AST_DEVICE_INUSE;
    			ao2_ref(lp, -1);
    			break;
    		}
    	}
    	ao2_iterator_destroy(&it);
    
    	if (res == AST_DEVICE_INVALID) {
    		ast_debug(3, "Checking if extension %s@%s exists (devicestate)\n", exten, context);
    		if (ast_exists_extension(NULL, context, exten, 1, NULL)) {
    			res = AST_DEVICE_NOT_INUSE;
    		}
    	}
    
    	return res;
    }
    
    
    static struct ast_multi_channel_blob *local_channel_optimization_blob(struct local_pvt *p,
    		struct ast_json *json_object)
    
    	struct ast_multi_channel_blob *payload;
    
    	RAII_VAR(struct ast_channel_snapshot *, local_one_snapshot, NULL, ao2_cleanup);
    	RAII_VAR(struct ast_channel_snapshot *, local_two_snapshot, NULL, ao2_cleanup);
    
    
    	local_one_snapshot = ast_channel_snapshot_get_latest(ast_channel_uniqueid(p->base.owner));
    
    		return NULL;
    
    	local_two_snapshot = ast_channel_snapshot_get_latest(ast_channel_uniqueid(p->base.chan));
    
    		return NULL;
    
    	payload = ast_multi_channel_blob_create(json_object);
    
    		return NULL;
    
    	}
    	ast_multi_channel_blob_add_channel(payload, "1", local_one_snapshot);
    	ast_multi_channel_blob_add_channel(payload, "2", local_two_snapshot);
    
    
    	return payload;
    
    }
    
    /*! \brief Callback for \ref ast_unreal_pvt_callbacks \ref optimization_started_cb */
    
    static void local_optimization_started_cb(struct ast_unreal_pvt *base, struct ast_channel *source,
    		enum ast_unreal_channel_indicator dest, unsigned int id)
    
    	RAII_VAR(struct ast_json *, json_object, ast_json_null(), ast_json_unref);
    	RAII_VAR(struct ast_multi_channel_blob *, payload, NULL, ao2_cleanup);
    	RAII_VAR(struct stasis_message *, msg, NULL, ao2_cleanup);
    
    	struct local_pvt *p = (struct local_pvt *)base;
    
    	if (!ast_local_optimization_begin_type()) {
    		return;
    	}
    
    
    	json_object = ast_json_pack("{s: i, s: i}",
    			"dest", dest, "id", id);
    
    	if (!json_object) {
    		return;
    	}
    
    	payload = local_channel_optimization_blob(p, json_object);
    	if (!payload) {
    		return;
    	}
    
    	if (source) {
    		RAII_VAR(struct ast_channel_snapshot *, source_snapshot, NULL, ao2_cleanup);
    
    		source_snapshot = ast_channel_snapshot_get_latest(ast_channel_uniqueid(source));
    
    		if (!source_snapshot) {
    			return;
    		}
    
    		ast_multi_channel_blob_add_channel(payload, "source", source_snapshot);
    	}
    
    	msg = stasis_message_create(ast_local_optimization_begin_type(), payload);
    	if (!msg) {
    		return;
    	}
    
    	stasis_publish(ast_channel_topic(p->base.owner), msg);
    
    }
    
    /*! \brief Callback for \ref ast_unreal_pvt_callbacks \ref optimization_finished_cb */
    
    static void local_optimization_finished_cb(struct ast_unreal_pvt *base, int success, unsigned int id)
    
    	RAII_VAR(struct ast_json *, json_object, ast_json_null(), ast_json_unref);
    	RAII_VAR(struct ast_multi_channel_blob *, payload, NULL, ao2_cleanup);
    	RAII_VAR(struct stasis_message *, msg, NULL, ao2_cleanup);
    
    	struct local_pvt *p = (struct local_pvt *)base;
    
    	if (!ast_local_optimization_end_type()) {
    		return;
    	}
    
    
    	json_object = ast_json_pack("{s: i, s: i}", "success", success, "id", id);
    
    	if (!json_object) {
    		return;
    	}
    
    	payload = local_channel_optimization_blob(p, json_object);
    	if (!payload) {
    		return;
    	}
    
    	msg = stasis_message_create(ast_local_optimization_end_type(), payload);
    	if (!msg) {
    		return;
    	}
    
    	stasis_publish(ast_channel_topic(p->base.owner), msg);
    
    }
    
    static struct ast_manager_event_blob *local_message_to_ami(struct stasis_message *message)
    {
    	struct ast_multi_channel_blob *obj = stasis_message_data(message);
    	struct ast_json *blob = ast_multi_channel_blob_get_json(obj);
    	struct ast_channel_snapshot *local_snapshot_one;
    	struct ast_channel_snapshot *local_snapshot_two;
    	RAII_VAR(struct ast_str *, local_channel_one, NULL, ast_free);
    	RAII_VAR(struct ast_str *, local_channel_two, NULL, ast_free);
    
    	RAII_VAR(struct ast_str *, event_buffer, NULL, ast_free);
    
    	const char *event;
    
    	local_snapshot_one = ast_multi_channel_blob_get_channel(obj, "1");
    	local_snapshot_two = ast_multi_channel_blob_get_channel(obj, "2");
    	if (!local_snapshot_one || !local_snapshot_two) {
    
    	local_channel_one = ast_manager_build_channel_state_string_prefix(local_snapshot_one, "LocalOne");
    	local_channel_two = ast_manager_build_channel_state_string_prefix(local_snapshot_two, "LocalTwo");
    
    	if (!event_buffer || !local_channel_one || !local_channel_two) {
    
    	if (stasis_message_type(message) == ast_local_optimization_begin_type()) {
    
    		struct ast_channel_snapshot *source_snapshot;
    		RAII_VAR(struct ast_str *, source_str, NULL, ast_free);
    		const char *dest_uniqueid;
    
    		source_snapshot = ast_multi_channel_blob_get_channel(obj, "source");
    		if (source_snapshot) {
    			source_str = ast_manager_build_channel_state_string_prefix(source_snapshot, "Source");
    			if (!source_str) {
    				return NULL;
    			}
    		}
    
    		dest_uniqueid = ast_json_object_get(blob, "dest") == AST_UNREAL_OWNER ?
    				local_snapshot_one->uniqueid : local_snapshot_two->uniqueid;
    
    
    		if (source_str) {
    			ast_str_append(&event_buffer, 0, "%s", ast_str_buffer(source_str));
    		}
    		ast_str_append(&event_buffer, 0, "DestUniqueId: %s\r\n", dest_uniqueid);
    		ast_str_append(&event_buffer, 0, "Id: %u\r\n", (unsigned int) ast_json_integer_get(ast_json_object_get(blob, "id")));
    
    	} else if (stasis_message_type(message) == ast_local_optimization_end_type()) {
    		event = "LocalOptimizationEnd";
    
    		ast_str_append(&event_buffer, 0, "Success: %s\r\n", ast_json_integer_get(ast_json_object_get(blob, "success")) ? "Yes" : "No");
    		ast_str_append(&event_buffer, 0, "Id: %u\r\n", (unsigned int) ast_json_integer_get(ast_json_object_get(blob, "id")));
    
    	} else if (stasis_message_type(message) == ast_local_bridge_type()) {
    		event = "LocalBridge";
    		ast_str_append(&event_buffer, 0, "Context: %s\r\n", ast_json_string_get(ast_json_object_get(blob, "context")));
    		ast_str_append(&event_buffer, 0, "Exten: %s\r\n", ast_json_string_get(ast_json_object_get(blob, "exten")));
    		ast_str_append(&event_buffer, 0, "LocalOptimization: %s\r\n", ast_json_is_true(ast_json_object_get(blob, "can_optimize")) ? "Yes" : "No");
    	} else {
    		return NULL;
    	}
    
    	return ast_manager_event_blob_create(EVENT_FLAG_CALL, event,
    
    		"%s",
    		ast_str_buffer(local_channel_one),
    		ast_str_buffer(local_channel_two),
    		ast_str_buffer(event_buffer));
    
     * \brief Post the \ref ast_local_bridge_type \ref stasis message
    
     * \param p local_pvt to raise the local bridge message
    
    static void publish_local_bridge_message(struct local_pvt *p)
    
    	RAII_VAR(struct ast_multi_channel_blob *, multi_blob, NULL, ao2_cleanup);
    	RAII_VAR(struct ast_json *, blob, NULL, ast_json_unref);
    	RAII_VAR(struct stasis_message *, msg, NULL, ao2_cleanup);
    	RAII_VAR(struct ast_channel_snapshot *, one_snapshot, NULL, ao2_cleanup);
    	RAII_VAR(struct ast_channel_snapshot *, two_snapshot, NULL, ao2_cleanup);
    
    	struct ast_channel *owner;
    	struct ast_channel *chan;
    
    
    	if (!ast_local_bridge_type()) {
    		return;
    	}
    
    
    	ast_unreal_lock_all(&p->base, &chan, &owner);
    
    
    	blob = ast_json_pack("{s: s, s: s, s: b}",
    		"context", p->context,
    		"exten", p->exten,
    
    		"can_optimize", !ast_test_flag(&p->base, AST_UNREAL_NO_OPTIMIZATION));
    
    	if (!blob) {
    
    	}
    
    	multi_blob = ast_multi_channel_blob_create(blob);
    	if (!multi_blob) {
    
    	one_snapshot = ast_channel_snapshot_get_latest(ast_channel_uniqueid(owner));
    
    	if (!one_snapshot) {
    
    	two_snapshot = ast_channel_snapshot_get_latest(ast_channel_uniqueid(chan));
    
    	if (!two_snapshot) {
    
    	}
    
    	ast_multi_channel_blob_add_channel(multi_blob, "1", one_snapshot);
    	ast_multi_channel_blob_add_channel(multi_blob, "2", two_snapshot);
    
    
    	msg = stasis_message_create(ast_local_bridge_type(), multi_blob);
    
    	if (!msg) {
    
    	stasis_publish(ast_channel_topic(owner), msg);
    
    end:
    	ast_channel_unlock(owner);
    	ast_channel_unref(owner);
    
    	ast_channel_unlock(chan);
    	ast_channel_unref(chan);
    
    	ao2_unlock(&p->base);
    
    }
    
    int ast_local_setup_bridge(struct ast_channel *ast, struct ast_bridge *bridge, struct ast_channel *swap, struct ast_bridge_features *features)
    {
    	struct local_pvt *p;
    	struct local_pvt *found;
    	int res = -1;
    
    	/* Sanity checks. */
    	if (!ast || !bridge) {
    		ast_bridge_features_destroy(features);
    		return -1;
    	}
    
    	ast_channel_lock(ast);
    	p = ast_channel_tech_pvt(ast);
    	ast_channel_unlock(ast);
    
    	found = p ? ao2_find(locals, p, 0) : NULL;
    	if (found) {
    		ao2_lock(found);
    		if (found->type == LOCAL_CALL_ACTION_DIALPLAN
    			&& found->base.owner
    			&& found->base.chan
    			&& !ast_test_flag(&found->base, AST_UNREAL_CARETAKER_THREAD)) {
    			ao2_ref(bridge, +1);
    			if (swap) {
    				ast_channel_ref(swap);
    			}
    			found->type = LOCAL_CALL_ACTION_BRIDGE;
    			found->action.bridge.join = bridge;
    			found->action.bridge.swap = swap;
    			found->action.bridge.features = features;
    			res = 0;
    		} else {
    			ast_bridge_features_destroy(features);
    		}
    		ao2_unlock(found);
    		ao2_ref(found, -1);
    	}
    
    	return res;
    }
    
    int ast_local_setup_masquerade(struct ast_channel *ast, struct ast_channel *masq)
    {
    	struct local_pvt *p;
    	struct local_pvt *found;
    	int res = -1;
    
    	/* Sanity checks. */
    	if (!ast || !masq) {
    		return -1;
    	}
    
    	ast_channel_lock(ast);
    	p = ast_channel_tech_pvt(ast);
    	ast_channel_unlock(ast);
    
    	found = p ? ao2_find(locals, p, 0) : NULL;
    	if (found) {
    		ao2_lock(found);
    		if (found->type == LOCAL_CALL_ACTION_DIALPLAN
    			&& found->base.owner
    			&& found->base.chan
    			&& !ast_test_flag(&found->base, AST_UNREAL_CARETAKER_THREAD)) {
    			ast_channel_ref(masq);
    			found->type = LOCAL_CALL_ACTION_MASQUERADE;
    			found->action.masq = masq;
    			res = 0;
    		}
    		ao2_unlock(found);
    		ao2_ref(found, -1);
    	}
    
    	return res;
    }
    
    /*! \brief Initiate new call, part of PBX interface
     *         dest is the dial string */
    static int local_call(struct ast_channel *ast, const char *dest, int timeout)
    {
    	struct local_pvt *p = ast_channel_tech_pvt(ast);
    	int pvt_locked = 0;
    
    	struct ast_channel *owner = NULL;
    	struct ast_channel *chan = NULL;
    	int res;
    	char *reduced_dest = ast_strdupa(dest);
    	char *slash;
    	const char *chan_cid;
    
    	if (!p) {
    		return -1;
    	}
    
    	/* since we are letting go of channel locks that were locked coming into
    	 * this function, then we need to give the tech pvt a ref */
    	ao2_ref(p, 1);
    	ast_channel_unlock(ast);
    
    	ast_unreal_lock_all(&p->base, &chan, &owner);
    	pvt_locked = 1;
    
    	if (owner != ast) {
    		res = -1;
    		goto return_cleanup;
    	}
    
    	if (!owner || !chan) {
    		res = -1;
    		goto return_cleanup;
    	}
    
    	ast_unreal_call_setup(owner, chan);
    
    	/*
    	 * If the local channel has /n on the end of it, we need to lop
    	 * that off for our argument to setting up the CC_INTERFACES
    	 * variable.
    	 */
    	if ((slash = strrchr(reduced_dest, '/'))) {
    		*slash = '\0';
    	}
    	ast_set_cc_interfaces_chanvar(chan, reduced_dest);
    
    	ao2_unlock(p);
    	pvt_locked = 0;
    
    	ast_channel_unlock(owner);
    
    	chan_cid = S_COR(ast_channel_caller(chan)->id.number.valid,
    		ast_channel_caller(chan)->id.number.str, NULL);
    	if (chan_cid) {
    		chan_cid = ast_strdupa(chan_cid);
    	}
    	ast_channel_unlock(chan);
    
    	res = -1;
    	switch (p->type) {
    	case LOCAL_CALL_ACTION_DIALPLAN:
    		if (!ast_exists_extension(NULL, p->context, p->exten, 1, chan_cid)) {
    			ast_log(LOG_NOTICE, "No such extension/context %s@%s while calling Local channel\n",
    				p->exten, p->context);
    		} else {
    
    
    			/* Start switch on sub channel */
    			res = ast_pbx_start(chan);
    		}
    		break;
    	case LOCAL_CALL_ACTION_BRIDGE:
    
    		ast_answer(chan);
    		res = ast_bridge_impart(p->action.bridge.join, chan, p->action.bridge.swap,
    
    			p->action.bridge.features, AST_BRIDGE_IMPART_CHAN_INDEPENDENT);
    
    		ao2_ref(p->action.bridge.join, -1);
    		p->action.bridge.join = NULL;
    		ao2_cleanup(p->action.bridge.swap);
    		p->action.bridge.swap = NULL;
    		p->action.bridge.features = NULL;
    		break;
    	case LOCAL_CALL_ACTION_MASQUERADE:
    
    		res = ast_channel_move(p->action.masq, chan);
    
    		if (!res) {
    			/* Chan is now an orphaned zombie.  Destroy it. */
    			ast_hangup(chan);
    		}
    		p->action.masq = ast_channel_unref(p->action.masq);
    		break;
    	}
    	if (!res) {
    		ao2_lock(p);
    		ast_set_flag(&p->base, AST_UNREAL_CARETAKER_THREAD);
    		ao2_unlock(p);
    	}
    
    	/* we already unlocked them, clear them here so the cleanup label won't touch them. */
    	owner = ast_channel_unref(owner);
    	chan = ast_channel_unref(chan);
    
    return_cleanup:
    	if (p) {
    		if (pvt_locked) {
    			ao2_unlock(p);
    		}
    		ao2_ref(p, -1);
    	}
    	if (chan) {
    		ast_channel_unlock(chan);
    		ast_channel_unref(chan);
    	}
    
    	/*
    	 * owner is supposed to be == to ast, if it is, don't unlock it
    	 * because ast must exit locked
    	 */
    	if (owner) {
    		if (owner != ast) {
    			ast_channel_unlock(owner);
    			ast_channel_lock(ast);
    		}
    		ast_channel_unref(owner);
    	} else {
    		/* we have to exit with ast locked */
    		ast_channel_lock(ast);
    	}
    
    	return res;
    }
    
    /*! \brief Hangup a call through the local proxy channel */
    static int local_hangup(struct ast_channel *ast)
    {
    	struct local_pvt *p = ast_channel_tech_pvt(ast);
    	int res;
    
    	if (!p) {
    		return -1;
    	}
    
    	/* give the pvt a ref to fulfill calling requirements. */
    	ao2_ref(p, +1);
    	res = ast_unreal_hangup(&p->base, ast);
    	if (!res) {
    		int unlink;
    
    		ao2_lock(p);
    		unlink = !p->base.owner && !p->base.chan;
    		ao2_unlock(p);
    		if (unlink) {
    			ao2_unlink(locals, p);
    		}
    	}
    	ao2_ref(p, -1);
    
    	return res;
    }
    
    /*!
     * \internal
     * \brief struct local_pvt destructor.
     *
     * \param vdoomed Object to destroy.
     *
     * \return Nothing
     */
    static void local_pvt_destructor(void *vdoomed)
    {
    	struct local_pvt *doomed = vdoomed;
    
    	switch (doomed->type) {
    	case LOCAL_CALL_ACTION_DIALPLAN:
    		break;
    	case LOCAL_CALL_ACTION_BRIDGE:
    		ao2_cleanup(doomed->action.bridge.join);
    		ao2_cleanup(doomed->action.bridge.swap);
    		ast_bridge_features_destroy(doomed->action.bridge.features);
    		break;
    	case LOCAL_CALL_ACTION_MASQUERADE:
    		ao2_cleanup(doomed->action.masq);
    		break;
    	}
    	ast_unreal_destructor(&doomed->base);
    }
    
    /*! \brief Create a call structure */
    static struct local_pvt *local_alloc(const char *data, struct ast_format_cap *cap)
    {
    	struct local_pvt *pvt;
    	char *parse;
    	char *context;
    	char *opts;
    
    	pvt = (struct local_pvt *) ast_unreal_alloc(sizeof(*pvt), local_pvt_destructor, cap);
    	if (!pvt) {
    		return NULL;
    	}
    
    	pvt->base.callbacks = &local_unreal_callbacks;
    
    
    	parse = ast_strdupa(data);
    
    	/*
    	 * Local channels intercept MOH by default.
    	 *
    	 * This is a silly default because it represents state held by
    	 * the local channels.  Unless local channel optimization is
    	 * disabled, the state will dissapear when the local channels
    	 * optimize out.
    	 */
    	ast_set_flag(&pvt->base, AST_UNREAL_MOH_INTERCEPT);
    
    	/* Look for options */
    	if ((opts = strchr(parse, '/'))) {
    		*opts++ = '\0';
    		if (strchr(opts, 'n')) {
    			ast_set_flag(&pvt->base, AST_UNREAL_NO_OPTIMIZATION);
    		}
    		if (strchr(opts, 'j')) {
    			if (ast_test_flag(&pvt->base, AST_UNREAL_NO_OPTIMIZATION)) {
    				ast_set_flag(&pvt->base.jb_conf, AST_JB_ENABLED);
    			} else {
    				ast_log(LOG_ERROR, "You must use the 'n' option with the 'j' option to enable the jitter buffer\n");
    			}
    		}
    		if (strchr(opts, 'm')) {
    			ast_clear_flag(&pvt->base, AST_UNREAL_MOH_INTERCEPT);
    		}
    	}
    
    	/* Look for a context */
    	if ((context = strchr(parse, '@'))) {
    		*context++ = '\0';
    	}
    
    	ast_copy_string(pvt->context, S_OR(context, "default"), sizeof(pvt->context));
    	ast_copy_string(pvt->exten, parse, sizeof(pvt->exten));
    	snprintf(pvt->base.name, sizeof(pvt->base.name), "%s@%s", pvt->exten, pvt->context);
    
    	return pvt; /* this is returned with a ref */
    }
    
    /*! \brief Part of PBX interface */
    
    static struct ast_channel *local_request(const char *type, struct ast_format_cap *cap, const struct ast_assigned_ids *assignedids, const struct ast_channel *requestor, const char *data, int *cause)
    
    {
    	struct local_pvt *p;
    	struct ast_channel *chan;
    	struct ast_callid *callid;
    
    	/* Allocate a new private structure and then Asterisk channels */
    	p = local_alloc(data, cap);
    	if (!p) {
    		return NULL;
    	}
    	callid = ast_read_threadstorage_callid();
    	chan = ast_unreal_new_channels(&p->base, &local_tech, AST_STATE_DOWN, AST_STATE_RING,
    
    		p->exten, p->context, assignedids, requestor, callid);
    
    	if (chan) {
    		ao2_link(locals, p);
    	}
    	if (callid) {
    		ast_callid_unref(callid);
    	}
    	ao2_ref(p, -1); /* kill the ref from the alloc */
    
    	return chan;
    }
    
    /*! \brief CLI command "local show channels" */
    static char *locals_show(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
    {
    	struct local_pvt *p;
    	struct ao2_iterator it;
    
    	switch (cmd) {
    	case CLI_INIT:
    		e->command = "local show channels";
    		e->usage =
    			"Usage: local show channels\n"
    			"       Provides summary information on active local proxy channels.\n";
    		return NULL;
    	case CLI_GENERATE:
    		return NULL;
    	}
    
    	if (a->argc != 3) {
    		return CLI_SHOWUSAGE;
    	}
    
    	if (ao2_container_count(locals) == 0) {
    		ast_cli(a->fd, "No local channels in use\n");
    		return RESULT_SUCCESS;
    	}
    
    	it = ao2_iterator_init(locals, 0);
    	while ((p = ao2_iterator_next(&it))) {
    		ao2_lock(p);
    		ast_cli(a->fd, "%s -- %s\n",
    			p->base.owner ? ast_channel_name(p->base.owner) : "<unowned>",
    			p->base.name);
    		ao2_unlock(p);
    		ao2_ref(p, -1);
    	}
    	ao2_iterator_destroy(&it);