[170] Fix WS listeners not being able to bind to an IP.

Closes eclipse-mosquitto#170. Thanks to minghuadev.

Bug: eclipse-mosquitto#170

ChangeLog.txt

@@ -16,6 +16,8 @@ Broker:
 - Fix reconnecting for bridges that use TLS on Windows. Closes #154.
 - Broker and bridges can now cope with unknown incoming PUBACK, PUBREC,
   PUBREL, PUBCOMP without disconnecting. Closes #57.
+- Fix websockets listeners not being able to bind to an IP address. Closes
+  #170.
 
 Client library:
 - Fix the case where a message received just before the keepalive timer

man/mosquitto.conf.5.xml

@@ -629,17 +629,23 @@
 					</listitem>
 				</varlistentry>
 				<varlistentry>
-					<term><option>listener</option> <replaceable>port</replaceable></term>
+					<term><option>listener</option> <replaceable>port</replaceable> <replaceable><optional>bind address/host</optional></replaceable></term>
 					<listitem>
 						<para>Listen for incoming network connection on the
 							specified port. A second optional argument allows
 							the listener to be bound to a specific ip
 							address/hostname. If this variable is used and
-							neither <option>bind_address</option> nor
-							<option>port</option> are used then the default
-							listener will not be started. This option may be
-							specified multiple times. See also the
-							<option>mount_point</option> option.</para>
+							neither the global <option>bind_address</option>
+							nor <option>port</option> options are used then the
+							default listener will not be started.</para>
+						<para>The <option>bind address/host</option> option
+							allows this listener to be bound to a specific IP
+							address by passing an IP address or hostname. For
+							websockets listeners, it is only possible to pass
+							an IP address here.</para>
+						<para>This option may be specified multiple times. See
+							also the <option>mount_point</option>
+							option.</para>
 						<para>Not reloaded on reload signal.</para>
 					</listitem>
 				</varlistentry>

mosquitto.conf

@@ -271,6 +271,8 @@
 # this case, mosquitto will attempt to bind the listener to that 
 # address and so restrict access to the associated network and 
 # interface. By default, mosquitto will listen on all interfaces.
+# Note that for a websockets listener it is not possible to bind to a host
+# name.
 # listener port-number [ip address/host name]
 #listener
 

src/websockets.c

@@ -584,6 +584,7 @@ struct libwebsocket_context *mosq_websockets_init(struct _mqtt3_listener *listen
 	}
 
 	memset(&info, 0, sizeof(info));
+	info.iface = listener->host;
 	info.port = listener->port;
 	info.protocols = p;
 	info.gid = -1;