Merge "ARI: Detect duplicate channel IDs" into 13

include/asterisk/channel.h

@@ -4669,4 +4669,16 @@ int ast_channel_feature_hooks_append(struct ast_channel *chan, struct ast_bridge
  */
 int ast_channel_feature_hooks_replace(struct ast_channel *chan, struct ast_bridge_features *features);
 
+enum ast_channel_error {
+	/* Unable to determine what error occurred. */
+	AST_CHANNEL_ERROR_UNKNOWN,
+	/* Channel with this ID already exists */
+	AST_CHANNEL_ERROR_ID_EXISTS,
+};
+
+/*!
+ * \brief Get error code for latest channel operation.
+ */
+enum ast_channel_error ast_channel_errno(void);
+
 #endif /* _ASTERISK_CHANNEL_H */

include/asterisk/channel_internal.h

@@ -25,3 +25,5 @@ int ast_channel_internal_is_finalized(struct ast_channel *chan);
 void ast_channel_internal_cleanup(struct ast_channel *chan);
 int ast_channel_internal_setup_topics(struct ast_channel *chan);
 
+void ast_channel_internal_errno_set(enum ast_channel_error error);
+enum ast_channel_error ast_channel_internal_errno(void);

main/channel.c

@@ -767,6 +767,27 @@ static const struct ast_channel_tech null_tech = {
 
 static void ast_channel_destructor(void *obj);
 static void ast_dummy_channel_destructor(void *obj);
+static int ast_channel_by_uniqueid_cb(void *obj, void *arg, void *data, int flags);
+
+static int does_id_conflict(const char *uniqueid)
+{
+	struct ast_channel *conflict;
+	int length = 0;
+
+	if (ast_strlen_zero(uniqueid)) {
+		return 0;
+	}
+
+	conflict = ast_channel_callback(ast_channel_by_uniqueid_cb, (char *) uniqueid, &length, OBJ_NOLOCK);
+	if (conflict) {
+		ast_log(LOG_ERROR, "Channel Unique ID '%s' already in use by channel %s(%p)\n",
+			uniqueid, ast_channel_name(conflict), conflict);
+		ast_channel_unref(conflict);
+		return 1;
+	}
+
+	return 0;
+}
 
 /*! \brief Create a new channel structure */
 static struct ast_channel * attribute_malloc __attribute__((format(printf, 15, 0)))
@@ -940,16 +961,33 @@ __ast_channel_alloc_ap(int needqueue, int state, const char *cid_num, const char
 		ast_channel_tech_set(tmp, &null_tech);
 	}
 
-	ast_channel_internal_finalize(tmp);
-
-	ast_atomic_fetchadd_int(&chancount, +1);
-
 	/* You might scream "locking inversion" at seeing this but it is actually perfectly fine.
 	 * Since the channel was just created nothing can know about it yet or even acquire it.
 	 */
 	ast_channel_lock(tmp);
 
-	ao2_link(channels, tmp);
+	ao2_lock(channels);
+
+	if (assignedids && (does_id_conflict(assignedids->uniqueid) || does_id_conflict(assignedids->uniqueid2))) {
+		ast_channel_internal_errno_set(AST_CHANNEL_ERROR_ID_EXISTS);
+		ao2_unlock(channels);
+		/* This is a bit unorthodox, but we can't just call ast_channel_stage_snapshot_done()
+		 * because that will result in attempting to publish the channel snapshot. That causes
+		 * badness in some places, such as CDRs. So we need to manually clear the flag on the
+		 * channel that says that a snapshot is being cleared.
+		 */
+		ast_clear_flag(ast_channel_flags(tmp), AST_FLAG_SNAPSHOT_STAGE);
+		ast_channel_unlock(tmp);
+		return ast_channel_unref(tmp);
+	}
+
+	ast_channel_internal_finalize(tmp);
+
+	ast_atomic_fetchadd_int(&chancount, +1);
+
+	ao2_link_flags(channels, tmp, OBJ_NOLOCK);
+
+	ao2_unlock(channels);
 
 	if (endpoint) {
 		ast_endpoint_add_channel(endpoint, tmp);
@@ -10842,3 +10880,8 @@ int ast_channel_feature_hooks_replace(struct ast_channel *chan, struct ast_bridg
 {
 	return channel_feature_hooks_set_full(chan, features, 1);
 }
+
+enum ast_channel_error ast_channel_errno(void)
+{
+	return ast_channel_internal_errno();
+}

main/channel_internal_api.c

@@ -1484,6 +1484,7 @@ static int pvt_cause_cmp_fn(void *obj, void *vstr, int flags)
 struct ast_channel *__ast_channel_internal_alloc(void (*destructor)(void *obj), const struct ast_assigned_ids *assignedids, const struct ast_channel *requestor, const char *file, int line, const char *function)
 {
 	struct ast_channel *tmp;
+
 #if defined(REF_DEBUG)
 	tmp = __ao2_alloc_debug(sizeof(*tmp), destructor,
 		AO2_ALLOC_OPT_LOCK_MUTEX, "", file, line, function, 1);
@@ -1675,3 +1676,25 @@ int ast_channel_internal_setup_topics(struct ast_channel *chan)
 
 	return 0;
 }
+
+AST_THREADSTORAGE(channel_errno);
+
+void ast_channel_internal_errno_set(enum ast_channel_error error)
+{
+	enum ast_channel_error *error_code = ast_threadstorage_get(&channel_errno, sizeof(*error_code));
+	if (!error_code) {
+		return;
+	}
+
+	*error_code = error;
+}
+
+enum ast_channel_error ast_channel_internal_errno(void)
+{
+	enum ast_channel_error *error_code = ast_threadstorage_get(&channel_errno, sizeof(*error_code));
+	if (!error_code) {
+		return AST_CHANNEL_ERROR_UNKNOWN;
+	}
+
+	return *error_code;
+}

res/ari/resource_channels.c

@@ -1109,7 +1109,12 @@ static void ari_channels_handle_originate_with_id(const char *args_endpoint,
 	}
 
 	if (ast_dial_prerun(dial, other, format_cap)) {
-		ast_ari_response_alloc_failed(response);
+		if (ast_channel_errno() == AST_CHANNEL_ERROR_ID_EXISTS) {
+			ast_ari_response_error(response, 409, "Conflict",
+				"Channel with given unique ID already exists");
+		} else {
+			ast_ari_response_alloc_failed(response);
+		}
 		ast_dial_destroy(dial);
 		ast_free(origination);
 		ast_channel_cleanup(other);

res/res_ari_channels.c

@@ -253,6 +253,7 @@ static void ast_ari_channels_originate_cb(
 	case 500: /* Internal Server Error */
 	case 501: /* Not Implemented */
 	case 400: /* Invalid parameters for originating a channel. */
+	case 409: /* Channel with given unique ID already exists. */
 		is_valid = 1;
 		break;
 	default:
@@ -483,6 +484,7 @@ static void ast_ari_channels_originate_with_id_cb(
 	case 500: /* Internal Server Error */
 	case 501: /* Not Implemented */
 	case 400: /* Invalid parameters for originating a channel. */
+	case 409: /* Channel with given unique ID already exists. */
 		is_valid = 1;
 		break;
 	default:

rest-api/api-docs/channels.json

@@ -142,6 +142,10 @@
 						{
 							"code": 400,
 							"reason": "Invalid parameters for originating a channel."
+						},
+						{
+							"code": 409,
+							"reason": "Channel with given unique ID already exists."
 						}
 					]
 				}
@@ -298,6 +302,10 @@
 						{
 							"code": 400,
 							"reason": "Invalid parameters for originating a channel."
+						},
+						{
+							"code": 409,
+							"reason": "Channel with given unique ID already exists."
 						}
 					]
 				},