[rygel] core: Add configuration option for V1 downgrade

[Jens Georg <jensgeorg src gnome org>]

commit cd772514ea0970e9cd26a98f66da7ae3817f48c4
Author: Jens Georg <mail jensge org>
Date:   Thu Nov 24 13:54:48 2011 +0100

    core: Add configuration option for V1 downgrade

 TODO                          |    3 --
 data/rygel.conf               |    9 ++++++++
 doc/man/rygel.conf.xml        |   11 +++++++++
 src/rygel/rygel-v1-hacks.vala |   46 +++++++++++++++++++++++++++++++++++++---
 4 files changed, 62 insertions(+), 7 deletions(-)
---
diff --git a/TODO b/TODO
index 1f1b336..eccd876 100644
--- a/TODO
+++ b/TODO
@@ -64,9 +64,6 @@
   * Start rygel as part of user session.
     * Remove relavent code from UI code.
 
-  * XBox hacks:
-    * Config for device hacks user-agent.
-
   * Transcoding:
     * Make use of encodebin when it's ready (update README/wiki afterwards).
     * Use h264 instead of mpeg2 video?
diff --git a/data/rygel.conf b/data/rygel.conf
index 25e852a..0c8c63a 100644
--- a/data/rygel.conf
+++ b/data/rygel.conf
@@ -68,6 +68,15 @@ allow-upload=true
 # Allow deletion of media folders and files?
 allow-deletion=true
 
+# Semicolon-separated list of device user-agents (or parts thereof) that need
+# a downgrade in the UPnP device versions
+# WARNING /!\: Only change this setting when told to do so or when you know
+#              what you're doing. If you find that adding your device makes it
+#              working with Rygel, please file a bug at
+#              https://bugzilla.gnome.org/enter_bug.cgi?product=Rygel&component=IOP
+#              so we can include it in future releases.
+#force-downgrade-for=Allegro-Software-WebClient;SEC_HHP_Galaxy S/1.0
+
 # Plugin specific sections
 #
 # Some options are generic and some are specific to each plugin.
diff --git a/doc/man/rygel.conf.xml b/doc/man/rygel.conf.xml
index 61d74ee..b306529 100644
--- a/doc/man/rygel.conf.xml
+++ b/doc/man/rygel.conf.xml
@@ -263,6 +263,17 @@ man(1), man(7), http://www.tldp.org/HOWTO/Man-Page/
           <para>If <option>allow-upload</option> is <userinput>true</userinput>, use this folder to store uploaded pictures. It defaults to <userinput>@PICTURES@</userinput> which expands to the default directory for picture files (usually <filename><envar>$HOME</envar>/Pictures</filename>).</para>
         </listitem>
       </varlistentry>
+      <varlistentry>
+        <term>
+          <option>force-downgrade-for</option>
+        </term>
+        <listitem>
+          <para>Semicolon-separated list of device user-agents (or parts thereof) which need a forced downgrade to <userinput>MediaServer:1</userinput> and/or <userinput>ContentDirectory:1</userinput>.</para>
+          <para><warning>
+              <para>Only use this parameter if you know what your&apos;re doing or are being told to do so; overriding the default value might cause incompatibilites. If you find that adding your device here enables its usage with Rygel, please  <ulink url="https://bugzilla.gnome.org/enter_bug.cgi?product=Rygel&amp;component=IOP";>file an IOP bug</ulink> so we can include it into the default configuration.</para>
+            </warning></para>
+        </listitem>
+      </varlistentry>
     </variablelist>
     <para>Sections for plugins are denoted with <option>[PluginName]</option>
       and can contain options specific to a plugin (see below)  as well these common options:
diff --git a/src/rygel/rygel-v1-hacks.vala b/src/rygel/rygel-v1-hacks.vala
index d8c9d46..68d67f6 100644
--- a/src/rygel/rygel-v1-hacks.vala
+++ b/src/rygel/rygel-v1-hacks.vala
@@ -26,15 +26,53 @@ using GUPnP;
 /**
  * Various devices that need a downgrade to MediaServer:1 and
  * ContentDirectory:1 because they ignore that higher versions are
- * backwards-compatible.
+ * required to be backwards-compatible.
  */
 internal class Rygel.V1Hacks : ClientHacks {
-    private const string AGENT = ".*Allegro-Software-WebClient.*|.*SEC_HHP_Galaxy S/1\\.0.*";
+    private const string DEFAULT_AGENT = ".*Allegro-Software-WebClient.*|" +
+                                         ".*SEC_HHP_Galaxy S/1\\.0.*";
     private const string DMS = "urn:schemas-upnp-org:device:MediaServer";
     private const string DMS_V1 = DMS + ":1";
+    private const string MATCHING_PATTERN = ".*%s.*";
+
+    private static string agent_pattern;
+
+    /**
+     * Read the user-agent snippets from the config file and generate the
+     * regular expression string for matching.
+     *
+     * Returns: A regular expression pattern matching any of the configured
+     *          user-agents.
+     */
+    private static string generate_agent_pattern () {
+        if (likely (agent_pattern != null)) {
+            return agent_pattern;
+        }
+
+        var config = MetaConfig.get_default ();
+        agent_pattern = DEFAULT_AGENT;
+        try {
+            var raw_agents = config.get_string_list ("general",
+                                                     "force-downgrade-for");
+            var agents = new string[0];
+            foreach (var agent in raw_agents) {
+                agents += MATCHING_PATTERN.printf
+                                        (Regex.escape_string (agent));
+            }
+
+            if (agents.length > 0) {
+                agent_pattern = string.joinv ("|", agents);
+            }
+        } catch (Error error) {}
+
+        debug ("V1 downgrade will be applied for devices matching %s",
+               agent_pattern);
+
+        return agent_pattern;
+    }
 
     public V1Hacks () throws ClientHacksError, RegexError {
-        base (AGENT);
+        base (generate_agent_pattern ());
     }
 
     public V1Hacks.for_action (ServiceAction action)
@@ -45,7 +83,7 @@ internal class Rygel.V1Hacks : ClientHacks {
 
     public V1Hacks.for_headers (MessageHeaders headers)
                                   throws ClientHacksError {
-        base (AGENT, headers);
+        base (generate_agent_pattern (), headers);
     }
 
     public void apply_on_device (RootDevice device,