A big one...

This is the merge of the forward-loop branch. The main change here is that call-forwards can no longer loop.
This is accomplished by creating a datastore on the calling channel which has a linked list of all devices
dialed. If a forward happens, then the local channel which is created inherits the datastore. If, through this
progression of forwards and datastore inheritance, a device is attempted to be dialed a second time, it will simply
be skipped and a warning message will be printed to the CLI. After the dialing has been completed, the datastore
is detached from the channel and destroyed.

This change also introduces some side effects to the code which I shall enumerate here:

1. Datastore inheritance has been backported from trunk into 1.4
2. A large chunk of code has been removed from app_dial. This chunk is the section of code
   which handles the call forward case after the channel has been requested but before it has
   been called. This was removed because call-forwarding still works fine without it, it makes the
   code less error-prone should it need changing, and it made this set of changes much less painful
   to just have the forwarding handled in one place in each module.
3. Two new files, global_datastores.h and .c have been added. These are necessary since the datastore
   which is attached to the channel may be created and attached in either app_dial or app_queue, so they
   need a common place to find the datastore info. This approach was taken in case similar datastores are
   needed in the future, there will be a common place to add them.


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@90735 65c4cc65-6c06-0410-ace0-fbb531ad65f3

apps/app_dial.c

@@ -61,6 +61,7 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 #include "asterisk/manager.h"
 #include "asterisk/privacy.h"
 #include "asterisk/stringfields.h"
+#include "asterisk/global_datastores.h"
 
 static char *app = "Dial";
 
@@ -303,7 +304,6 @@ AST_APP_OPTIONS(dial_exec_options, {
 struct dial_localuser {
 	struct ast_channel *chan;
 	unsigned int flags;
-	int forwards;
 	struct dial_localuser *next;
 };
 
@@ -322,8 +322,6 @@ static void hanguptree(struct dial_localuser *outgoing, struct ast_channel *exce
 	}
 }
 
-#define AST_MAX_FORWARDS   8
-
 #define AST_MAX_WATCHERS 256
 
 #define HANDLE_CAUSE(cause, chan) do { \
@@ -488,30 +486,23 @@ static struct ast_channel *wait_for_answer(struct ast_channel *in, struct dial_l
 					tech = "Local";
 				}
 				/* Before processing channel, go ahead and check for forwarding */
-				o->forwards++;
-				if (o->forwards < AST_MAX_FORWARDS) {
+				if (option_verbose > 2)
+					ast_verbose(VERBOSE_PREFIX_3 "Now forwarding %s to '%s/%s' (thanks to %s)\n", in->name, tech, stuff, c->name);
+				/* If we have been told to ignore forwards, just set this channel to null and continue processing extensions normally */
+				if (ast_test_flag(peerflags, OPT_IGNORE_FORWARDING)) {
 					if (option_verbose > 2)
-						ast_verbose(VERBOSE_PREFIX_3 "Now forwarding %s to '%s/%s' (thanks to %s)\n", in->name, tech, stuff, c->name);
-					/* If we have been told to ignore forwards, just set this channel to null and continue processing extensions normally */
-					if (ast_test_flag(peerflags, OPT_IGNORE_FORWARDING)) {
-						if (option_verbose > 2)
-							ast_verbose(VERBOSE_PREFIX_3 "Forwarding %s to '%s/%s' prevented.\n", in->name, tech, stuff);
-						c = o->chan = NULL;
-						cause = AST_CAUSE_BUSY;
-					} else {
-						/* Setup parameters */
-						if ((c = o->chan = ast_request(tech, in->nativeformats, stuff, &cause))) {
-							if (single)
-								ast_channel_make_compatible(o->chan, in);
-							ast_channel_inherit_variables(in, o->chan);
-						} else
-							ast_log(LOG_NOTICE, "Unable to create local channel for call forward to '%s/%s' (cause = %d)\n", tech, stuff, cause);
-					}
-				} else {
-					if (option_verbose > 2)
-						ast_verbose(VERBOSE_PREFIX_3 "Too many forwards from %s\n", c->name);
-					cause = AST_CAUSE_CONGESTION;
+						ast_verbose(VERBOSE_PREFIX_3 "Forwarding %s to '%s/%s' prevented.\n", in->name, tech, stuff);
 					c = o->chan = NULL;
+					cause = AST_CAUSE_BUSY;
+				} else {
+					/* Setup parameters */
+					if ((c = o->chan = ast_request(tech, in->nativeformats, stuff, &cause))) {
+						if (single)
+							ast_channel_make_compatible(o->chan, in);
+						ast_channel_inherit_variables(in, o->chan);
+						ast_channel_datastore_inherit(in, o->chan);
+					} else
+						ast_log(LOG_NOTICE, "Unable to create local channel for call forward to '%s/%s' (cause = %d)\n", tech, stuff, cause);
 				}
 				if (!c) {
 					ast_clear_flag(o, DIAL_STILLGOING);	
@@ -847,6 +838,8 @@ static int dial_exec_full(struct ast_channel *chan, void *data, struct ast_flags
 	);
 	struct ast_flags opts = { 0, };
 	char *opt_args[OPT_ARG_ARRAY_SIZE];
+	struct ast_datastore *datastore;
+	int fulldial = 0, num_dialed = 0;
 
 	if (ast_strlen_zero(data)) {
 		ast_log(LOG_WARNING, "Dial requires an argument (technology/number)\n");
@@ -1107,7 +1100,13 @@ static int dial_exec_full(struct ast_channel *chan, void *data, struct ast_flags
 		struct dial_localuser *tmp;
 		/* Get a technology/[device:]number pair */
 		char *number = cur;
+		char *interface = ast_strdupa(number);
 		char *tech = strsep(&number, "/");
+		/* find if we already dialed this interface */
+		int dialed = 0;
+		struct ast_dialed_interface *di;
+		AST_LIST_HEAD(, ast_dialed_interface) *dialed_interfaces;
+		num_dialed++;
 		if (!number) {
 			ast_log(LOG_WARNING, "Dial argument takes format (technology/[device:]number1)\n");
 			goto out;
@@ -1125,6 +1124,50 @@ static int dial_exec_full(struct ast_channel *chan, void *data, struct ast_flags
 		}
 		ast_copy_string(numsubst, number, sizeof(numsubst));
 		/* Request the peer */
+		if (!(datastore = ast_channel_datastore_find(chan, &dialed_interface_info, NULL))) {
+			if(!(datastore = ast_channel_datastore_alloc(&dialed_interface_info, NULL))) {
+				ast_log(LOG_WARNING, "Unable to create channel datastore for dialed interfaces. Aborting!\n"); 
+				free(tmp);
+				goto out;
+			}
+			else {
+				datastore->inheritance = DATASTORE_INHERIT_FOREVER;
+				if((dialed_interfaces = ast_calloc(1, sizeof(*dialed_interfaces)))) {
+					datastore->data = dialed_interfaces;
+					AST_LIST_HEAD_INIT(dialed_interfaces);
+					ast_channel_datastore_add(chan, datastore);
+				} else {
+					free(tmp);
+					goto out;
+				}
+			}
+		} else 
+			dialed_interfaces = datastore->data;
+		AST_LIST_LOCK(dialed_interfaces);
+		AST_LIST_TRAVERSE(dialed_interfaces, di, list) {
+			/* XXX case sensitive??? */
+			if(!strcasecmp(di->interface, interface)) {
+				dialed = 1;
+				break;
+			}
+		}
+		if(!dialed && strcasecmp(tech, "Local")) {
+			if(!(di = ast_calloc(1, sizeof(*di) + strlen(interface)))) {
+				AST_LIST_UNLOCK(dialed_interfaces);
+				free(tmp);
+				goto out;
+			}
+			strcpy(di->interface, interface);
+			AST_LIST_INSERT_TAIL(dialed_interfaces, di, list);
+		} else {
+			AST_LIST_UNLOCK(dialed_interfaces);
+			ast_log(LOG_WARNING, "Skipping dialing interface '%s' again since it has already been dialed\n", di->interface);
+			fulldial++;
+			free(tmp);
+			continue;
+		}
+		AST_LIST_UNLOCK(dialed_interfaces);
+
 		tmp->chan = ast_request(tech, chan->nativeformats, numsubst, &cause);
 		if (!tmp->chan) {
 			/* If we can't, just go on to the next call */
@@ -1135,51 +1178,8 @@ static int dial_exec_full(struct ast_channel *chan, void *data, struct ast_flags
 			free(tmp);
 			continue;
 		}
-		pbx_builtin_setvar_helper(tmp->chan, "DIALEDPEERNUMBER", numsubst);
-		if (!ast_strlen_zero(tmp->chan->call_forward)) {
-			char tmpchan[256];
-			char *stuff;
-			char *tech;
-			ast_copy_string(tmpchan, tmp->chan->call_forward, sizeof(tmpchan));
-			if ((stuff = strchr(tmpchan, '/'))) {
-				*stuff++ = '\0';
-				tech = tmpchan;
-			} else {
-				snprintf(tmpchan, sizeof(tmpchan), "%s@%s", tmp->chan->call_forward, tmp->chan->context);
-				stuff = tmpchan;
-				tech = "Local";
-			}
-			tmp->forwards++;
-			if (tmp->forwards < AST_MAX_FORWARDS) {
-				if (option_verbose > 2)
-					ast_verbose(VERBOSE_PREFIX_3 "Now forwarding %s to '%s/%s' (thanks to %s)\n", chan->name, tech, stuff, tmp->chan->name);
-				ast_hangup(tmp->chan);
-				/* If we have been told to ignore forwards, just set this channel to null and continue processing extensions normally */
-				if (ast_test_flag(&opts, OPT_IGNORE_FORWARDING)) {
-					tmp->chan = NULL;
-					cause = AST_CAUSE_BUSY;
-					if (option_verbose > 2)
-						ast_verbose(VERBOSE_PREFIX_3 "Forwarding %s to '%s/%s' prevented.\n", chan->name, tech, stuff);
-				} else {
-					tmp->chan = ast_request(tech, chan->nativeformats, stuff, &cause);
-				}
-				if (!tmp->chan)
-					ast_log(LOG_NOTICE, "Unable to create local channel for call forward to '%s/%s' (cause = %d)\n", tech, stuff, cause);
-				else
-					ast_channel_inherit_variables(chan, tmp->chan);
-			} else {
-				if (option_verbose > 2)
-					ast_verbose(VERBOSE_PREFIX_3 "Too many forwards from %s\n", tmp->chan->name);
-				ast_hangup(tmp->chan);
-				tmp->chan = NULL;
-				cause = AST_CAUSE_CONGESTION;
-			}
-			if (!tmp->chan) {
-				HANDLE_CAUSE(cause, chan);
-				free(tmp);
-				continue;
-			}
-		}
+
+				pbx_builtin_setvar_helper(tmp->chan, "DIALEDPEERNUMBER", numsubst);
 
 		/* Setup outgoing SDP to match incoming one */
 		ast_rtp_make_compatible(tmp->chan, chan, !outgoing && !rest);
@@ -1284,6 +1284,10 @@ static int dial_exec_full(struct ast_channel *chan, void *data, struct ast_flags
 
 	if (!outgoing) {
 		strcpy(status, "CHANUNAVAIL");
+		if(fulldial == num_dialed) {
+			res = -1;
+			goto out;
+		}
 	} else {
 		/* Our status will at least be NOANSWER */
 		strcpy(status, "NOANSWER");
@@ -1306,7 +1310,9 @@ static int dial_exec_full(struct ast_channel *chan, void *data, struct ast_flags
 
 	time(&start_time);
 	peer = wait_for_answer(chan, outgoing, &to, peerflags, &sentringing, status, sizeof(status), numbusy, numnochan, numcongestion, ast_test_flag(&opts, OPT_PRIORITY_JUMP), &result);
-	
+
+	ast_channel_datastore_remove(chan, datastore);
+	ast_channel_datastore_free(datastore);
 	if (!peer) {
 		if (result) {
 			res = result;

apps/app_queue.c

@@ -93,6 +93,7 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 #include "asterisk/devicestate.h"
 #include "asterisk/stringfields.h"
 #include "asterisk/astobj2.h"
+#include "asterisk/global_datastores.h"
 
 enum {
 	QUEUE_STRATEGY_RINGALL = 0,
@@ -2133,6 +2134,7 @@ static struct callattempt *wait_for_answer(struct queue_ent *qe, struct callatte
 						numnochan++;
 					} else {
 						ast_channel_inherit_variables(in, o->chan);
+						ast_channel_datastore_inherit(in, o->chan);
 						if (o->chan->cid.cid_num)
 							free(o->chan->cid.cid_num);
 						o->chan->cid.cid_num = ast_strdup(in->cid.cid_num);
@@ -2500,6 +2502,7 @@ static int try_calling(struct queue_ent *qe, const char *options, char *announce
 	int forwardsallowed = 1;
 	int callcompletedinsl;
 	struct ao2_iterator memi;
+	struct ast_datastore *datastore = ast_channel_datastore_find(qe->chan, &dialed_interface_info, NULL);
 
 	memset(&bridge_config, 0, sizeof(bridge_config));
 	time(&now);
@@ -2555,7 +2558,9 @@ static int try_calling(struct queue_ent *qe, const char *options, char *announce
 	memi = ao2_iterator_init(qe->parent->members, 0);
 	while ((cur = ao2_iterator_next(&memi))) {
 		struct callattempt *tmp = ast_calloc(1, sizeof(*tmp));
-
+		struct ast_dialed_interface *di;
+		int dialed = 0;
+		AST_LIST_HEAD(, ast_dialed_interface) *dialed_interfaces;
 		if (!tmp) {
 			ao2_ref(cur, -1);
 			ast_mutex_unlock(&qe->parent->lock);
@@ -2563,6 +2568,49 @@ static int try_calling(struct queue_ent *qe, const char *options, char *announce
 				AST_LIST_UNLOCK(&queues);
 			goto out;
 		}
+		if (!datastore) {
+			if(!(datastore = ast_channel_datastore_alloc(&dialed_interface_info, NULL))) {
+				ao2_ref(cur, -1);
+				ast_mutex_unlock(&qe->parent->lock);
+				if(use_weight)
+					AST_LIST_UNLOCK(&queues);
+				free(tmp);
+				goto out;
+			}
+			datastore->inheritance = DATASTORE_INHERIT_FOREVER;
+			dialed_interfaces = ast_calloc(1, sizeof(*dialed_interfaces));
+			datastore->data = dialed_interfaces;
+			AST_LIST_HEAD_INIT(dialed_interfaces);
+			ast_channel_datastore_add(qe->chan, datastore);
+		} else
+			dialed_interfaces = datastore->data;
+		AST_LIST_LOCK(dialed_interfaces);
+		AST_LIST_TRAVERSE(dialed_interfaces, di, list) {
+			/* XXX case sensitive ?? */
+			if(!strcasecmp(cur->interface, di->interface)) {
+				dialed = 1;
+				break;
+			}
+		}
+		if (!dialed && strncasecmp(cur->interface, "Local/", 6)) {
+			if(!(di = ast_calloc(1, sizeof(*di) + strlen(cur->interface)))) {
+				ao2_ref(cur, -1);
+				AST_LIST_UNLOCK(dialed_interfaces);
+				ast_mutex_unlock(&qe->parent->lock);
+				if(use_weight)
+					AST_LIST_UNLOCK(&queues);
+				free(tmp);
+				goto out;
+			}
+			strcpy(di->interface, cur->interface);
+			AST_LIST_INSERT_TAIL(dialed_interfaces, di, list);
+		} else {
+			AST_LIST_UNLOCK(dialed_interfaces);
+			ast_log(LOG_DEBUG, "Skipping dialing interface '%s' since it has already been dialed\n", di->interface);
+			free(tmp);
+			continue;
+		}
+		AST_LIST_UNLOCK(dialed_interfaces);
 		tmp->stillgoing = -1;
 		tmp->member = cur;
 		tmp->oldstatus = cur->status;
@@ -2593,6 +2641,8 @@ static int try_calling(struct queue_ent *qe, const char *options, char *announce
 	if (use_weight)
 		AST_LIST_UNLOCK(&queues);
 	lpeer = wait_for_answer(qe, outgoing, &to, &digit, numbusies, ast_test_flag(&(bridge_config.features_caller), AST_FEATURE_DISCONNECT), forwardsallowed);
+	ast_channel_datastore_remove(qe->chan, datastore);
+	ast_channel_datastore_free(datastore);
 	ast_mutex_lock(&qe->parent->lock);
 	if (qe->parent->strategy == QUEUE_STRATEGY_RRMEMORY) {
 		store_next(qe, outgoing);

channels/chan_local.c

@@ -467,6 +467,7 @@ static int local_call(struct ast_channel *ast, char *dest, int timeout)
 			AST_LIST_INSERT_TAIL(&p->chan->varshead, new, entries);
 		}
 	}
+	ast_channel_datastore_inherit(p->owner, p->chan);
 
 	/* Start switch on sub channel */
 	if (!(res = ast_pbx_start(p->chan)))

include/asterisk/channel.h

@@ -118,6 +118,7 @@ extern "C" {
 #include "asterisk/stringfields.h"
 #include "asterisk/compiler.h"
 
+#define DATASTORE_INHERIT_FOREVER	INT_MAX
 
 #define AST_MAX_FDS		8
 /*
@@ -148,6 +149,7 @@ struct ast_generator {
 /*! \brief Structure for a data store type */
 struct ast_datastore_info {
 	const char *type;		/*!< Type of data store */
+	void *(*duplicate)(void *data); /*!< Duplicate item data (used for inheritance) */
 	void (*destroy)(void *data);	/*!< Destroy function */
 };
 
@@ -156,6 +158,7 @@ struct ast_datastore {
 	char *uid;		/*!< Unique data store identifier */
 	void *data;		/*!< Contained data */
 	const struct ast_datastore_info *info;	/*!< Data store type information */
+	unsigned int inheritance;	/*!Number of levels this item will continue to be inherited */
 	AST_LIST_ENTRY(ast_datastore) entry; /*!< Used for easy linking */
 };
 
@@ -575,6 +578,9 @@ struct ast_datastore *ast_channel_datastore_alloc(const struct ast_datastore_inf
 /*! \brief Free a channel datastore structure */
 int ast_channel_datastore_free(struct ast_datastore *datastore);
 
+/*! \brief Inherit datastores from a parent to a child. */
+int ast_channel_datastore_inherit(struct ast_channel *from, struct ast_channel *to);
+
 /*! \brief Add a datastore to a channel */
 int ast_channel_datastore_add(struct ast_channel *chan, struct ast_datastore *datastore);
 

include/asterisk/global_datastores.h

@@ -0,0 +1,36 @@
+/*
+ * Asterisk -- An open source telephony toolkit.
+ *
+ * Copyright (C) 1999 - 2007, Digium, Inc.
+ *
+ * Mark Michelson <mmichelson@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 globally accessible channel datastores
+ * \author Mark Michelson <mmichelson@digium.com>
+ */
+
+#ifndef _ASTERISK_GLOBAL_DATASTORE_H
+#define _ASTERISK_GLOBAL_DATASTORE_H
+
+#include "asterisk/channel.h"
+
+extern const struct ast_datastore_info dialed_interface_info;
+
+struct ast_dialed_interface {
+	AST_LIST_ENTRY(ast_dialed_interface) list;
+	char interface[1];
+};
+
+#endif

main/Makefile

@@ -26,7 +26,7 @@ OBJS=	io.o sched.o logger.o frame.o loader.o config.o channel.o \
 	utils.o plc.o jitterbuf.o dnsmgr.o devicestate.o \
 	netsock.o slinfactory.o ast_expr2.o ast_expr2f.o \
 	cryptostub.o sha1.o http.o fixedjitterbuf.o abstract_jb.o \
-	strcompat.o threadstorage.o dial.o astobj2.o
+	strcompat.o threadstorage.o dial.o astobj2.o global_datastores.o
 
 # we need to link in the objects statically, not as a library, because
 # otherwise modules will not have them available if none of the static

main/channel.c

@@ -1317,6 +1317,23 @@ int ast_channel_datastore_free(struct ast_datastore *datastore)
 	return res;
 }
 
+int ast_channel_datastore_inherit(struct ast_channel *from, struct ast_channel *to)
+{
+	struct ast_datastore *datastore = NULL, *datastore2;
+
+	AST_LIST_TRAVERSE(&from->datastores, datastore, entry) {
+		if (datastore->inheritance > 0) {
+			datastore2 = ast_channel_datastore_alloc(datastore->info, datastore->uid);
+			if (datastore2) {
+				datastore2->data = datastore->info->duplicate(datastore->data);
+				datastore2->inheritance = datastore->inheritance == DATASTORE_INHERIT_FOREVER ? DATASTORE_INHERIT_FOREVER : datastore->inheritance - 1;
+				AST_LIST_INSERT_TAIL(&to->datastores, datastore2, entry);
+			}
+		}
+	}
+	return 0;
+}
+
 int ast_channel_datastore_add(struct ast_channel *chan, struct ast_datastore *datastore)
 {
 	int res = 0;

main/global_datastores.c

@@ -0,0 +1,78 @@
+/*
+ * Asterisk -- An open source telephony toolkit.
+ *
+ * Copyright (C) 1999 - 2007, Digium, Inc.
+ *
+ * Mark Michelson <mmichelson@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 globally-accessible datastore information and callbacks
+ *
+ * \author Mark Michelson <mmichelson@digium.com>
+ */
+
+#include "asterisk/global_datastores.h"
+#include "asterisk/linkedlists.h"
+
+static void dialed_interface_destroy(void *data)
+{
+	struct ast_dialed_interface *di = NULL;
+	AST_LIST_HEAD(, ast_dialed_interface) *dialed_interface_list = data;
+	
+	if (!dialed_interface_list)
+		return;
+
+	AST_LIST_LOCK(dialed_interface_list);
+	while ((di = AST_LIST_REMOVE_HEAD(dialed_interface_list, list)))
+		ast_free(di);
+	AST_LIST_UNLOCK(dialed_interface_list);
+
+	AST_LIST_HEAD_DESTROY(dialed_interface_list);
+	ast_free(dialed_interface_list);
+}
+
+static void *dialed_interface_duplicate(void *data)
+{
+	struct ast_dialed_interface *di = NULL;
+	AST_LIST_HEAD(, ast_dialed_interface) *old_list;
+	AST_LIST_HEAD(, ast_dialed_interface) *new_list = NULL;
+
+	if(!(old_list = data))
+		return NULL;
+
+	if(!(new_list = ast_calloc(1, sizeof(*new_list))))
+		return NULL;
+
+	AST_LIST_HEAD_INIT(new_list);
+	AST_LIST_LOCK(old_list);
+	AST_LIST_TRAVERSE(old_list, di, list) {
+		struct ast_dialed_interface *di2 = ast_calloc(1, sizeof(*di2) + strlen(di->interface));
+		if(!di2) {
+			AST_LIST_UNLOCK(old_list);
+			return NULL;
+		}
+		strcpy(di2->interface, di->interface);
+		AST_LIST_INSERT_TAIL(new_list, di2, list);
+	}
+	AST_LIST_UNLOCK(old_list);
+
+	return new_list;
+}
+
+const struct ast_datastore_info dialed_interface_info = {
+	.type ="dialed-interface",
+	.destroy = dialed_interface_destroy,
+	.duplicate = dialed_interface_duplicate,
+};