Add inheritance support to FEATURE()/FEATUREMAP().

The settings saved on the channel for FEATURE()/FEATUREMAP() were only
for that channel.  This patch adds the ability to have these settings
inherited to child channels if you set FEATURE(inherit)=yes.

Closes issue ASTERISK-21306.

Review: https://reviewboard.asterisk.org/r/2415/


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@385088 65c4cc65-6c06-0410-ace0-fbb531ad65f3

CHANGES

@@ -89,6 +89,10 @@ Features
  * PARKINGSLOT and PARKEDLOT channel variables will now be set for a parked
    channel even when comebactoorigin=yes
 
+ * You can now have the settings for a channel updated using the FEATURE()
+   and FEATUREMAP() functions inherited to child channels by setting
+   FEATURE(inherit)=yes.
+
 Logging
 -------------------
  * When performing queue pause/unpause on an interface without specifying an

main/features.c

@@ -438,6 +438,7 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 				<para>The allowed values are:</para>
 				<enumlist>
 					<enum name="parkingtime"><para>Specified in seconds.</para></enum>
+					<enum name="inherit"><para>Inherit feature settings made in FEATURE or FEATUREMAP to child channels.</para></enum>
 				</enumlist>
 			</parameter>
 		</syntax>
@@ -3333,11 +3334,31 @@ struct feature_ds {
 	 * \todo XXX This isn't pretty.  At some point it would be nice to have all
 	 * of the global / [general] options in a config object that we store here
 	 * instead of handling each one manually.
+	 *
+	 * \note If anything gets added here, don't forget to update
+	 * feature_ds_duplicate, as well.
 	 * */
 	unsigned int parkingtime;
 	unsigned int parkingtime_is_set:1;
 };
 
+static int feature_exten_hash(const void *obj, int flags)
+{
+	const struct feature_exten *fe = obj;
+	const char *sname = obj;
+
+	return ast_str_hash(flags & OBJ_KEY ? sname : fe->sname);
+}
+
+static int feature_exten_cmp(void *obj, void *arg, int flags)
+{
+	const struct feature_exten *fe = obj, *fe2 = arg;
+	const char *sname = arg;
+
+	return !strcmp(fe->sname, flags & OBJ_KEY ? sname : fe2->sname) ?
+			CMP_MATCH | CMP_STOP : 0;
+}
+
 static void feature_ds_destroy(void *data)
 {
 	struct feature_ds *feature_ds = data;
@@ -3350,28 +3371,32 @@ static void feature_ds_destroy(void *data)
 	ast_free(feature_ds);
 }
 
-static const struct ast_datastore_info feature_ds_info = {
-	.type = "FEATURE",
-	.destroy = feature_ds_destroy,
-};
-
-static int feature_exten_hash(const void *obj, int flags)
+static void *feature_ds_duplicate(void *data)
 {
-	const struct feature_exten *fe = obj;
-	const char *sname = obj;
+	struct feature_ds *old_ds = data;
+	struct feature_ds *new_ds;
 
-	return ast_str_hash(flags & OBJ_KEY ? sname : fe->sname);
-}
+	if (!(new_ds = ast_calloc(1, sizeof(*new_ds)))) {
+		return NULL;
+	}
 
-static int feature_exten_cmp(void *obj, void *arg, int flags)
-{
-	const struct feature_exten *fe = obj, *fe2 = arg;
-	const char *sname = arg;
+	if (old_ds->feature_map) {
+		ao2_ref(old_ds->feature_map, +1);
+		new_ds->feature_map = old_ds->feature_map;
+	}
 
-	return !strcmp(fe->sname, flags & OBJ_KEY ? sname : fe2->sname) ?
-			CMP_MATCH | CMP_STOP : 0;
+	new_ds->parkingtime = old_ds->parkingtime;
+	new_ds->parkingtime_is_set = old_ds->parkingtime_is_set;
+
+	return new_ds;
 }
 
+static const struct ast_datastore_info feature_ds_info = {
+	.type = "FEATURE",
+	.destroy = feature_ds_destroy,
+	.duplicate = feature_ds_duplicate,
+};
+
 /*!
  * \internal
  * \brief Find or create feature datastore on a channel
@@ -3411,6 +3436,19 @@ static struct feature_ds *get_feature_ds(struct ast_channel *chan)
 	return feature_ds;
 }
 
+static struct ast_datastore *get_feature_chan_ds(struct ast_channel *chan)
+{
+	struct ast_datastore *ds;
+
+	if (!(ds = ast_channel_datastore_find(chan, &feature_ds_info, NULL))) {
+		/* Hasn't been created yet.  Trigger creation. */
+		get_feature_ds(chan);
+		ds = ast_channel_datastore_find(chan, &feature_ds_info, NULL);
+	}
+
+	return ds;
+}
+
 /*!
  * \internal
  * \brief Get the extension for a given builtin feature
@@ -8964,6 +9002,16 @@ static int feature_read(struct ast_channel *chan, const char *cmd, char *data,
 
 	if (!strcasecmp(data, "parkingtime")) {
 		snprintf(buf, len, "%u", get_parkingtime(chan, NULL) / 1000);
+	} else if (!strcasecmp(data, "inherit")) {
+		struct ast_datastore *ds;
+		unsigned int inherit;
+
+		ast_channel_lock(chan);
+		ds = get_feature_chan_ds(chan);
+		inherit = ds ? ds->inheritance : 0;
+		ast_channel_unlock(chan);
+
+		snprintf(buf, len, "%s", inherit ? "yes" : "no");
 	} else {
 		ast_log(LOG_WARNING, "Invalid argument '%s' to FEATURE()\n", data);
 		res = -1;
@@ -8994,6 +9042,11 @@ static int feature_write(struct ast_channel *chan, const char *cmd, char *data,
 			feature_ds->parkingtime_is_set = 0;
 			res = -1;
 		}
+	} else if (!strcasecmp(data, "inherit")) {
+		struct ast_datastore *ds;
+		if ((ds = get_feature_chan_ds(chan))) {
+			ds->inheritance = ast_true(value) ? DATASTORE_INHERIT_FOREVER : 0;
+		}
 	} else {
 		ast_log(LOG_WARNING, "Invalid argument '%s' to FEATURE()\n", data);
 		res = -1;