Add configuration for MQTT protocol version, username, password

Default MQTT version is 5
Default username, password are block. Up to 255 chars each.

src/sbbs3/mqtt.c

@@ -242,7 +242,14 @@ int mqtt_connect(struct mqtt* mqtt, const char* bind_address)
 		return MQTT_FAILURE;
 
 #ifdef USE_MOSQUITTO
-	mosquitto_int_option(mqtt->handle, MOSQ_OPT_PROTOCOL_VERSION, MQTT_PROTOCOL_V5);
+	char* username = mqtt->cfg->mqtt.username;
+	char* password = mqtt->cfg->mqtt.password;
+	if(*username == '\0')
+		username = NULL;
+	if(*password == '\0')
+		password = NULL;
+	mosquitto_int_option(mqtt->handle, MOSQ_OPT_PROTOCOL_VERSION, mqtt->cfg->mqtt.protocol_version);
+	mosquitto_username_pw_set(mqtt->handle, username, password);
 	return mosquitto_connect_bind(mqtt->handle,
 		mqtt->cfg->mqtt.broker_addr,
 		mqtt->cfg->mqtt.broker_port,

src/sbbs3/scfgdefs.h

@@ -367,8 +367,11 @@ struct mqtt_cfg {
 	BOOL		enabled;
 	char		broker_addr[128];
 	uint16_t	broker_port;
+	char		username[256];
+	char		password[256];
 	int			keepalive;
 	int			qos;
+	int			protocol_version;
 };
 
 typedef struct 

src/sbbs3/scfglib1.c

@@ -204,10 +204,13 @@ BOOL read_main_cfg(scfg_t* cfg, char* error, size_t maxerrlen)
 	/*****************/
 	section = iniGetParsedSection(sections, "mqtt", /* cut: */TRUE);
 	cfg->mqtt.enabled = iniGetBool(section, NULL, "enabled", FALSE);
+	SAFECOPY(cfg->mqtt.username, iniGetString(section, NULL, "username", "", value));
+	SAFECOPY(cfg->mqtt.password, iniGetString(section, NULL, "password", "", value));
 	SAFECOPY(cfg->mqtt.broker_addr, iniGetString(section, NULL, "broker_addr", "127.0.0.1", value));
 	cfg->mqtt.broker_port = iniGetUInt16(section, NULL, "broker_port", IPPORT_MQTT);
 	cfg->mqtt.keepalive = iniGetInteger(section, NULL, "keepalive", 10);
 	cfg->mqtt.qos = iniGetInteger(section, NULL, "qos", 0);
+	cfg->mqtt.protocol_version = iniGetInteger(section, NULL, "protocol_version", 5);
 
 	/***********/
 	/* Modules */

src/sbbs3/scfgsave.c

@@ -212,8 +212,11 @@ BOOL write_main_cfg(scfg_t* cfg, int backup_level)
 		iniSetBool(&ini, name, "enabled", cfg->mqtt.enabled, NULL);
 		iniSetString(&ini, name, "broker_addr", cfg->mqtt.broker_addr, NULL);
 		iniSetUInt16(&ini, name, "broker_port", cfg->mqtt.broker_port, NULL);
+		iniSetInteger(&ini, name, "protocol_version", cfg->mqtt.protocol_version, NULL);
 		iniSetInteger(&ini, name, "keepalive", cfg->mqtt.keepalive, NULL);
 		iniSetInteger(&ini, name, "qos", cfg->mqtt.qos, NULL);
+		iniSetString(&ini, name, "username", cfg->mqtt.username, NULL);
+		iniSetString(&ini, name, "password", cfg->mqtt.password, NULL);
 	}
 
 	{