Master-Slave Aggregating Relay (multiple master setup)

conf/icecast.xml.in

@@ -108,6 +108,21 @@
     <!--<master-update-interval>120</master-update-interval>-->
     <!--<master-password>hackme</master-password>-->
 
+    <!-- Aggregation
+         useful for aggregating all the mounts of any number of master relays.
+    -->
+
+    <!--
+    <master>
+        <server>127.0.0.1</server>
+        <port>8001</port>
+        <username>relay</username>
+        <password>hackme</password>
+        <namespace>master1</namespace>
+        <on-demand>1</on-demand>
+    </master>
+    -->
+
     <!-- Setting this makes all relays on-demand unless overridden, this is
          useful for master relays which do not have <relay> definitions here.
          The default is 0 -->

doc/relaying.html

@@ -35,6 +35,9 @@ <h3 id="type-of-relays">Type of Relays</h3>
 will also periodically check the master server to see if any new mountpoints have attached and if so will relay those
 as well.  </p>
 
+  <p>This "master-slave" type relay has been extended to support aggregation so that multiple masters can be given
+and the slave will "aggregate" all of the mountpoints for those master servers. </p>
+
   <p>The second type of relay is a “single-broadcast” relay. In this case, the slave server is configured with a
 server IP, port and mount and only the mountpoint specified is relayed. In order to relay a broadcast stream on
 a Shoutcast server, you must use the “single-broadcast” relay and specify a mountpoint of <code>/</code>.</p>
@@ -61,6 +64,36 @@ <h3 id="setting-up-a-master-slave-relay">Setting Up a Master-Slave Relay</h3>
 
 </div>
 
+<div class="article">
+  <h3 id="setting-up-a-master-slave-aggregating-relay">Setting Up a Master-Slave Aggregating Relay</h3>
+  <p>In order to setup a relay of this type all servers (the one you wish to relay and the one doing the relaying)
+need to be Icecast 2 servers. The following configuration snippet is used as an example:</p>
+
+  <div class="highlight"><pre><code class="language-xml" data-lang="xml"><span class="nt">&lt;master-update-interval&gt;</span>120<span class="nt">&lt;/master-update-interval&gt;</span>
+<span class="nt">&lt;master&gt;</span>
+    <span class="nt">&lt;server&gt;</span>192.168.1.11<span class="nt">&lt;/server&gt;</span>
+    <span class="nt">&lt;port&gt;</span>8001<span class="nt">&lt;/port&gt;</span>
+    <span class="nt">&lt;namespace&gt;</span>/upstream1<span class="nt">&lt;/namespace&gt;</span>
+    <span class="nt">&lt;password&gt;</span>hackme<span class="nt">&lt;/password&gt;</span>
+    <span class="nt">&lt;on-demand&gt;</span>1<span class="nt">&lt;/on-demand&gt;</span>
+<span class="nt">&lt;/master&gt;</span>
+<span class="nt">&lt;master&gt;</span>
+    <span class="nt">&lt;server&gt;</span>192.168.1.12<span class="nt">&lt;/server&gt;</span>
+    <span class="nt">&lt;port&gt;</span>8001<span class="nt">&lt;/port&gt;</span>
+    <span class="nt">&lt;password&gt;</span>hackme<span class="nt">&lt;/password&gt;</span>
+<span class="nt">&lt;/master&gt;</span>
+</code></pre></div>
+
+  <p>In this example, this configuration is setup in the server which will be doing the relaying (slave server).
+The master servers in this case need not be configured (and actually they are unaware of the relaying being performed)
+as relays. When the slave server is started, it will connect to each of the master servers located at 192.168.1.11:8001
+and 192.168.1.12:8001 and will begin to relay all mountpoints connected to the master servers. Additionally,
+every master-update-interval (120 seconds in this case) the slave server will poll the master servers to see if any new
+mountpoints have connected, and if so, the slave server will relay those as well. Note that all mountpoints of the master
+server at 192.168.1.11:8001 will have the namespace "/upstream1" prepended to it's mountpoints. </p>
+
+</div>
+
 <div class="article">
   <h3 id="setting-up-a-single-broadcast-relay">Setting Up a Single-Broadcast Relay</h3>
   <p>In this case, the master server need not be an Icecast 2 server. Supported master servers for a single-broadcast

src/cfgfile.c

@@ -133,6 +133,7 @@ static void _parse_http_headers(xmlDocPtr                   doc,
                                 xmlNodePtr                  node,
                                 ice_config_http_header_t  **http_headers);
 
+static void _parse_master(xmlDocPtr doc, xmlNodePtr node, ice_config_t *c);
 static void _parse_relay(xmlDocPtr doc, xmlNodePtr node, ice_config_t *c);
 static void _parse_mount(xmlDocPtr doc, xmlNodePtr node, ice_config_t *c);
 
@@ -487,6 +488,7 @@ void config_clear(ice_config_t *c)
 {
     ice_config_dir_t    *dirnode,
                         *nextdirnode;
+    master_server        *master;
     relay_server        *relay,
                         *nextrelay;
     mount_proxy         *mount,
@@ -529,6 +531,11 @@ void config_clear(ice_config_t *c)
 
     while ((c->listen_sock = config_clear_listener(c->listen_sock)));
 
+    master = c->master;
+    while (master) {
+        master = master_free(master);
+    }
+
     thread_mutex_lock(&(_locks.relay_lock));
     relay = c->relay;
     while (relay) {
@@ -934,6 +941,8 @@ static void _parse_root(xmlDocPtr       doc,
             _parse_limits(doc, node->xmlChildrenNode, configuration);
         } else if (xmlStrcmp(node->name, XMLSTR("http-headers")) == 0) {
             _parse_http_headers(doc, node->xmlChildrenNode, &(configuration->http_headers));
+        } else if (xmlStrcmp(node->name, XMLSTR("master")) == 0) {
+            _parse_master(doc, node->xmlChildrenNode, configuration);
         } else if (xmlStrcmp(node->name, XMLSTR("relay")) == 0) {
             _parse_relay(doc, node->xmlChildrenNode, configuration);
         } else if (xmlStrcmp(node->name, XMLSTR("mount")) == 0) {
@@ -1579,6 +1588,81 @@ static void _parse_http_headers(xmlDocPtr                   doc,
         xmlFree(value);
 }
 
+static void _parse_master(xmlDocPtr      doc,
+                         xmlNodePtr     node,
+                         ice_config_t  *configuration)
+{
+    char         *tmp;
+    master_server *master     = calloc(1, sizeof(master_server));
+    master_server *current   = configuration->master;
+    master_server *last      = NULL;
+
+    while(current) {
+        last = current;
+        current = current->next;
+    }
+
+    if (last) {
+        last->next = master;
+    } else {
+        configuration->master = master;
+    }
+
+    master->next         = NULL;
+    master->on_demand    = configuration->on_demand;
+    master->server       = NULL;
+    master->username     = (char *) xmlCharStrdup(configuration->master_username);
+    if (configuration->master_password)
+        master->password = (char *) xmlCharStrdup(configuration->master_password);
+    master->namespace    = NULL;
+
+    do {
+        if (node == NULL)
+            break;
+        if (xmlIsBlankNode(node))
+            continue;
+
+        if (xmlStrcmp(node->name, XMLSTR("server")) == 0) {
+            if (master->server)
+                xmlFree(master->server);
+            master->server = (char *)xmlNodeListGetString(doc,
+                node->xmlChildrenNode, 1);
+        } else if (xmlStrcmp(node->name, XMLSTR("port")) == 0) {
+            tmp = (char *)xmlNodeListGetString(doc, node->xmlChildrenNode, 1);
+            if (tmp) {
+                master->port = atoi(tmp);
+                xmlFree(tmp);
+            } else {
+                ICECAST_LOG_WARN("<port> setting must not be empty.");
+            }
+        } else if (xmlStrcmp(node->name, XMLSTR("username")) == 0) {
+            if (master->username)
+                xmlFree(master->username);
+            master->username = (char *)xmlNodeListGetString(doc,
+                node->xmlChildrenNode, 1);
+        } else if (xmlStrcmp(node->name, XMLSTR("password")) == 0) {
+            if (master->password)
+                xmlFree(master->password);
+            master->password = (char *)xmlNodeListGetString(doc, 
+                node->xmlChildrenNode, 1);
+        } else if (xmlStrcmp(node->name, XMLSTR("namespace")) == 0) {
+            if (master->namespace)
+                xmlFree(master->namespace);
+            master->namespace = (char *)xmlNodeListGetString(doc, 
+                node->xmlChildrenNode, 1);
+        } else if (xmlStrcmp(node->name, XMLSTR("on-demand")) == 0) {
+            tmp = (char *)xmlNodeListGetString(doc, node->xmlChildrenNode, 1);
+            master->on_demand = util_str_to_bool(tmp);
+            if (tmp)
+                xmlFree(tmp);
+        }
+    } while ((node = node->next));
+
+    if (master->server == NULL) {
+        ICECAST_LOG_WARN("<server> is required for <master>.");
+    }
+}
+
 static void _parse_relay(xmlDocPtr      doc,
                          xmlNodePtr     node,
                          ice_config_t  *configuration)

src/cfgfile.h

@@ -218,6 +218,7 @@ typedef struct ice_config_tag {
     /* is TLS supported by the server? */
     int tls_ok;
 
+    master_server *master;
     relay_server *relay;
 
     mount_proxy *mounts;