app_confbridge: Don't emit warnings on valid configurations.

The numeric bridge profile options `internal_sample_rate` and
`maximum_sample_rate` are documented to accept the special values
`auto` and `none`, respectively. While these values currently work,
they also emit warnings when used which could be confusing for users.

In passing, also ensure that we only accept the documented range of
sample rate values between 8000 and 192000.

Fixes #546

apps/confbridge/conf_config_parser.c

@@ -2220,6 +2220,30 @@ static int user_template_handler(const struct aco_option *opt, struct ast_variab
 	return conf_find_user_profile(NULL, var->value, u_profile) ? 0 : -1;
 }
 
+static int sample_rate_handler(const struct aco_option *opt, struct ast_variable *var, void *obj)
+{
+	struct bridge_profile *b_profile = obj;
+	unsigned int *slot;
+
+	if (!strcasecmp(var->name, "internal_sample_rate")) {
+		slot = &b_profile->internal_sample_rate;
+		if (!strcasecmp(var->value, "auto")) {
+			*slot = 0;
+			return 0;
+		}
+	} else if (!strcasecmp(var->name, "maximum_sample_rate")) {
+		slot = &b_profile->maximum_sample_rate;
+		if (!strcasecmp(var->value, "none")) {
+			*slot = 0;
+			return 0;
+		}
+	} else {
+		return -1;
+	}
+
+	return ast_parse_arg(var->value, PARSE_UINT32 | PARSE_IN_RANGE, slot, 8000, 192000);
+}
+
 static int bridge_template_handler(const struct aco_option *opt, struct ast_variable *var, void *obj)
 {
 	struct bridge_profile *b_profile = obj;
@@ -2437,10 +2461,9 @@ int conf_load_config(void)
 	/* Bridge options */
 	aco_option_register(&cfg_info, "type", ACO_EXACT, bridge_types, NULL, OPT_NOOP_T, 0, 0);
 	aco_option_register(&cfg_info, "jitterbuffer", ACO_EXACT, bridge_types, "no", OPT_BOOLFLAG_T, 1, FLDSET(struct bridge_profile, flags), USER_OPT_JITTERBUFFER);
-	/* "auto" will fail to parse as a uint, but we use PARSE_DEFAULT to set the value to 0 in that case, which is the value that auto resolves to */
-	aco_option_register(&cfg_info, "internal_sample_rate", ACO_EXACT, bridge_types, "0", OPT_UINT_T, PARSE_DEFAULT, FLDSET(struct bridge_profile, internal_sample_rate), 0);
+	aco_option_register_custom(&cfg_info, "internal_sample_rate", ACO_EXACT, bridge_types, "auto", sample_rate_handler, 0);
 	aco_option_register(&cfg_info, "binaural_active", ACO_EXACT, bridge_types, "no", OPT_BOOLFLAG_T, 1, FLDSET(struct bridge_profile, flags), BRIDGE_OPT_BINAURAL_ACTIVE);
-	aco_option_register(&cfg_info, "maximum_sample_rate", ACO_EXACT, bridge_types, "0", OPT_UINT_T, PARSE_DEFAULT, FLDSET(struct bridge_profile, maximum_sample_rate), 0);
+	aco_option_register_custom(&cfg_info, "maximum_sample_rate", ACO_EXACT, bridge_types, "none", sample_rate_handler, 0);
 	aco_option_register_custom(&cfg_info, "mixing_interval", ACO_EXACT, bridge_types, "20", mix_interval_handler, 0);
 	aco_option_register(&cfg_info, "record_conference", ACO_EXACT, bridge_types, "no", OPT_BOOLFLAG_T, 1, FLDSET(struct bridge_profile, flags), BRIDGE_OPT_RECORD_CONFERENCE);
 	aco_option_register_custom(&cfg_info, "video_mode", ACO_EXACT, bridge_types, NULL, video_mode_handler, 0);