closes issue #11285, where an unload of a module that creates a dialplan context, causes a crash when you do a 'dialplan show' of that context. This is because the registrar string is defined in the module, and the stale pointer is traversed. The reporter offered a patch that would always strdup the registrar string, which is practical, but I preferred to destroy the created contexts in each module where one is created. That seemed more symmetric. There were only 6 place in asterisk where this is done: chan_sip, chan_iax2, chan_skinny, res_features, app_dial, and app_queue. The two apps destroyed the context, but left the contexts. All is fixed now and unloads should be dialplan friendly.

git-svn-id: http://svn.digium.com/svn/asterisk/trunk@89513 f38db490-d61c-443f-a65b-d21fe96a405b

6 files changed, 31 insertions, 2 deletions

diff --git a/apps/app_dial.c b/apps/app_dial.c
index a4d955778..714c38a85 100644
--- a/apps/app_dial.c
+++ b/apps/app_dial.c
@@ -1953,8 +1953,11 @@ static int unload_module(void)
 	res |= ast_unregister_application(rapp);
 
 	if ((con = ast_context_find("app_dial_gosub_virtual_context")))
+	{
 		ast_context_remove_extension2(con, "s", 1, NULL);
-
+		ast_context_destroy(con, "app_dial"); /* leave nothing behind */
+	}
+	
 	return res;
 }
 
diff --git a/apps/app_queue.c b/apps/app_queue.c
index 382982351..dc8454247 100644
--- a/apps/app_queue.c
+++ b/apps/app_queue.c
@@ -5516,6 +5516,7 @@ static int unload_module(void)
 
 	if ((con = ast_context_find("app_queue_gosub_virtual_context"))) {
 		ast_context_remove_extension2(con, "s", 1, NULL);
+		ast_context_destroy(con, "app_queue"); /* leave no trace */
 	}
 
 	clear_and_free_interfaces();
diff --git a/channels/chan_iax2.c b/channels/chan_iax2.c
index 6e2a0ab96..725d25758 100644
--- a/channels/chan_iax2.c
+++ b/channels/chan_iax2.c
@@ -11400,6 +11400,7 @@ static struct ast_cli_entry cli_iax2[] = {
 static int __unload_module(void)
 {
 	struct iax2_thread *thread = NULL;
+	struct ast_context *con;
 	int x;
 
 	/* Make sure threads do not hold shared resources when they are canceled */
@@ -11465,7 +11466,11 @@ static int __unload_module(void)
 
 	ao2_ref(peers, -1);
 	ao2_ref(users, -1);
-
+	
+	con = ast_context_find(regcontext);
+	if (con)
+		ast_context_destroy(con, "IAX2");
+	
 	return 0;
 }
 
diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index 4d651cf86..b81ac3f30 100644
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -555,6 +555,7 @@ static char default_mohsuggest[MAX_MUSICCLASS];	   /*!< Global setting for moh c
                                                     *   a bridged channel on hold */
 static int default_maxcallbitrate;	/*!< Maximum bitrate for call */
 static struct ast_codec_pref default_prefs;		/*!< Default codec prefs */
+static char used_context[AST_MAX_CONTEXT]; /*!< name of automatically created context for unloading */
 
 /*! \brief a place to store all global settings for the sip channel driver */
 struct sip_settings {
@@ -18191,6 +18192,7 @@ static int reload_config(enum channelreloadreason reason)
 			cleanup_stale_contexts(stringp, oldregcontext);
 			/* Create contexts if they don't exist already */
 			while ((context = strsep(&stringp, "&"))) {
+				ast_copy_string(used_context, context, sizeof(used_context));
 				if (!ast_context_find(context))
 					ast_context_create(NULL, context,"SIP");
 			}
@@ -19205,6 +19207,7 @@ static int load_module(void)
 static int unload_module(void)
 {
 	struct sip_pvt *p, *pl;
+	struct ast_context *con;
 	
 	/* First, take us out of the channel type list */
 	ast_channel_unregister(&sip_tech);
@@ -19274,6 +19277,9 @@ static int unload_module(void)
 	clear_sip_domains();
 	close(sipsock);
 	sched_context_destroy(sched);
+	con = ast_context_find(used_context);
+	if (con)
+		ast_context_destroy(con, "SIP");
 
 	return 0;
 }
diff --git a/channels/chan_skinny.c b/channels/chan_skinny.c
index 7640ef341..0422a2392 100644
--- a/channels/chan_skinny.c
+++ b/channels/chan_skinny.c
@@ -92,6 +92,7 @@ enum skinny_codecs {
 
 static int keep_alive = 120;
 static char vmexten[AST_MAX_EXTENSION];		/* Voicemail pilot number */
+static char used_context[AST_MAX_EXTENSION];		/* Voicemail pilot number */
 static char regcontext[AST_MAX_CONTEXT];	/* Context for auto-extension */
 static char date_format[6] = "D-M-Y";
 static char version_id[16] = "P002F202";
@@ -5508,6 +5509,7 @@ static int reload_config(void)
 			cleanup_stale_contexts(stringp, oldregcontext);
 			/* Create contexts if they don't exist already */
 			while ((context = strsep(&stringp, "&"))) {
+				ast_copy_string(used_context, context, sizeof(used_context));
 				if (!ast_context_find(context))
 					ast_context_create(NULL, context, "Skinny");
 			}
@@ -5705,6 +5707,7 @@ static int unload_module(void)
 	struct skinny_device *d;
 	struct skinny_line *l;
 	struct skinny_subchannel *sub;
+	struct ast_context *con;
 
 	ast_mutex_lock(&sessionlock);
 	/* Destroy all the interfaces and free their memory */
@@ -5762,6 +5765,10 @@ static int unload_module(void)
 	if (sched)
 		sched_context_destroy(sched);
 
+	con = ast_context_find(used_context);
+	if (con)
+		ast_context_destroy(con, "Skinny");
+	
 	return 0;
 }
 
diff --git a/res/res_features.c b/res/res_features.c
index 8bb8e5f38..31ce64b1a 100644
--- a/res/res_features.c
+++ b/res/res_features.c
@@ -3305,6 +3305,7 @@ static int load_module(void)
 
 static int unload_module(void)
 {
+	struct ast_context *con;
 	ast_manager_unregister("ParkedCalls");
 	ast_manager_unregister("Bridge");
 	ast_manager_unregister("Park");
@@ -3312,6 +3313,12 @@ static int unload_module(void)
 	ast_unregister_application(parkcall);
 	ast_unregister_application(app_bridge);
 	ast_devstate_prov_del("Park");
+	con = ast_context_find(parking_con);
+	if (con)
+		ast_context_destroy(con, registrar);
+	con = ast_context_find(parking_con_dial);
+	if (con)
+		ast_context_destroy(con, registrar); 	
 	return ast_unregister_application(parkedcall);
 }