[rygel/wip/dvd: 20/21] media-export: Query DVD structure information

[Jens Georg <jensgeorg src gnome org>]

commit 9626b5d7d4c6fea3e4c9b595dd2bd2ac93bdd773
Author: Jens Georg <jensg openismus com>
Date:   Sun Jul 14 14:55:12 2013 +0200

    media-export: Query DVD structure information
    
    Use lsdvd binary and its XML output for this to avoid effective GPL
    relicensing by using libdvdread explicitly.
    
    The output is cached so we only have to do this once ideally.

 configure.ac                                       |    1 +
 src/plugins/media-export/Makefile.am               |    1 +
 .../rygel-media-export-dvd-parser.vala             |  126 ++++++++++++++++++++
 .../media-export/rygel-media-export-harvester.vala |    3 +-
 .../rygel-media-export-metadata-extractor.vala     |   48 +++++---
 5 files changed, 160 insertions(+), 19 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 3e67688..671f364 100644
--- a/configure.ac
+++ b/configure.ac
@@ -160,6 +160,7 @@ AS_IF([test "x$with_media_engine" = "xgstreamer"],
                                gstreamer-pbutils-1.0 >= $GSTPBU_REQUIRED
                                libsoup-2.4 >= $LIBSOUP_REQUIRED
                                sqlite3 >= $LIBSQLITE3_REQUIRED
+                               libxml-2.0 >= $LIBXML_REQUIRED
                                uuid])
             RYGEL_PLUGIN_MEDIA_EXPORT_DEPS_VALAFLAGS="$RYGEL_COMMON_MODULES_VALAFLAGS --pkg gupnp-dlna-2.0 
--pkg gupnp-dlna-gst-2.0 --pkg gstreamer-tag-1.0 --pkg gstreamer-app-1.0 --pkg gstreamer-pbutils-1.0 --pkg 
sqlite3"
             AC_SUBST([RYGEL_PLUGIN_MEDIA_EXPORT_DEPS_VALAFLAGS])
diff --git a/src/plugins/media-export/Makefile.am b/src/plugins/media-export/Makefile.am
index 470fed6..f659b1c 100644
--- a/src/plugins/media-export/Makefile.am
+++ b/src/plugins/media-export/Makefile.am
@@ -7,6 +7,7 @@ librygel_media_export_la_SOURCES = \
        rygel-media-export-plugin.vala \
        rygel-media-export-database.vala \
        rygel-media-export-database-cursor.vala \
+       rygel-media-export-dvd-parser.vala \
        rygel-media-export-sqlite-wrapper.vala \
        rygel-media-export-db-container.vala \
        rygel-media-export-sql-factory.vala \
diff --git a/src/plugins/media-export/rygel-media-export-dvd-parser.vala 
b/src/plugins/media-export/rygel-media-export-dvd-parser.vala
new file mode 100644
index 0000000..b4a4fef
--- /dev/null
+++ b/src/plugins/media-export/rygel-media-export-dvd-parser.vala
@@ -0,0 +1,126 @@
+/*
+ * Copyright (C) 2013 Jens Georg <mail jensge org>.
+ *
+ * Author: Jens Georg <mail jensge org>
+ *
+ * This file is part of Rygel.
+ *
+ * Rygel is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * Rygel is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+internal class Rygel.MediaExport.DVDParser : GLib.Object {
+    /// URI to the image / toplevel directory
+    public File file { private get; construct; }
+
+    private File cache_file;
+
+    public DVDParser (File file) {
+        Object (file : file);
+    }
+
+    public override void constructed () {
+        unowned string user_cache = Environment.get_user_cache_dir ();
+        var cache_folder = Path.build_filename (user_cache,
+                                                "rygel",
+                                                "dvd-content");
+        DirUtils.create_with_parents (cache_folder, 0700);
+        var cache_path = Path.build_filename (cache_folder,
+                                              MediaCache.get_id (this.file));
+
+        this.cache_file = File.new_for_path (cache_path);
+    }
+
+    public async void run () {
+        var doc = yield this.get_information ();
+        if (doc != null) {
+            doc->children;
+        }
+    }
+
+    public async Xml.Doc* get_information () {
+        if (this.cache_file.query_exists ()) {
+            return Xml.Parser.read_file (this.cache_file.get_path (),
+                                         null,
+                                         Xml.ParserOption.NOERROR |
+                                         Xml.ParserOption.NOWARNING);
+        }
+
+        Pid pid;
+        int stdout_fd;
+
+        try {
+            Process.spawn_async_with_pipes (null,
+                                            { "/usr/bin/lsdvd",
+                                              "-Ox",
+                                              "-x",
+                                              "-q",
+                                              this.file.get_path (),
+                                              null },
+                                            null,
+                                            SpawnFlags.DO_NOT_REAP_CHILD |
+                                            SpawnFlags.STDERR_TO_DEV_NULL,
+                                            null,
+                                            out pid,
+                                            null,
+                                            out stdout_fd);
+            var data = new StringBuilder ();
+            var io_channel = new IOChannel.unix_new (stdout_fd);
+            var io_watch = io_channel.add_watch (IOCondition.IN |
+                                                 IOCondition.PRI,
+                                                 () => {
+                string line;
+
+                try {
+                    io_channel.read_to_end (out line, null);
+                    data.append (line);
+                } catch (Error error) { }
+
+                return true;
+            });
+
+            uint child_watch = 0;
+            child_watch = ChildWatch.add (pid, () => {
+                Source.remove (child_watch);
+                Source.remove (io_watch);
+                Process.close_pid (pid);
+
+                get_information.callback ();
+            });
+
+            yield;
+
+            try {
+                this.cache_file.replace_contents (data.str.data,
+                                                  null,
+                                                  false,
+                                                  FileCreateFlags.NONE,
+                                                  null);
+            } catch (Error rc_error) {
+                debug ("Failed to cache lsdvd output: %s", rc_error.message);
+            }
+
+            return Xml.Parser.read_memory (data.str,
+                                           (int) data.len,
+                                           null,
+                                           null,
+                                           Xml.ParserOption.NOERROR |
+                                           Xml.ParserOption.NOWARNING);
+        } catch (SpawnError error) {
+            debug ("Failed to run lsdvd: %s", error.message);
+        }
+
+        return null;
+    }
+}
diff --git a/src/plugins/media-export/rygel-media-export-harvester.vala 
b/src/plugins/media-export/rygel-media-export-harvester.vala
index d85489c..8fb7635 100644
--- a/src/plugins/media-export/rygel-media-export-harvester.vala
+++ b/src/plugins/media-export/rygel-media-export-harvester.vala
@@ -73,7 +73,8 @@ internal class Rygel.MediaExport.Harvester : GLib.Object {
                info.get_content_type () == "application/ogg" ||
                info.get_content_type () == "application/xml" ||
                info.get_content_type () == "text/xml" ||
-               info.get_content_type () == "text/plain";
+               info.get_content_type () == "text/plain" ||
+               info.get_content_type () == "application/x-cd-image";
     }
 
     /**
diff --git a/src/plugins/media-export/rygel-media-export-metadata-extractor.vala 
b/src/plugins/media-export/rygel-media-export-metadata-extractor.vala
index 6024cdc..41a5742 100644
--- a/src/plugins/media-export/rygel-media-export-metadata-extractor.vala
+++ b/src/plugins/media-export/rygel-media-export-metadata-extractor.vala
@@ -59,6 +59,8 @@ public class Rygel.MediaExport.MetadataExtractor: GLib.Object {
 
     private bool extract_metadata;
 
+    private DVDParser dvd_parser;
+
     public MetadataExtractor () {
         this.file_hash = new HashMap<string, File> ();
 
@@ -68,26 +70,36 @@ public class Rygel.MediaExport.MetadataExtractor: GLib.Object {
     }
 
     public void extract (File file, string content_type) {
-        if (this.extract_metadata && !content_type.has_prefix ("text/")) {
-            string uri = file.get_uri ();
-            try {
-                var gst_timeout = (ClockTime) (this.timeout * Gst.SECOND);
-
-                this.discoverer = new Discoverer (gst_timeout);
-            } catch (Error error) {
-                debug ("Failed to create a discoverer. Doing basic extraction.");
-                this.extract_basic_information (file, null, null);
-
-                return;
-            }
-            this.file_hash.set (uri, file);
-            this.discoverer.discovered.connect (on_done);
-            this.discoverer.start ();
-            this.discoverer.discover_uri_async (uri);
-            this.guesser = new GUPnPDLNA.ProfileGuesser (true, true);
-        } else {
+        if (!this.extract_metadata || content_type.has_prefix ("text/")) {
+            this.extract_basic_information (file, null, null);
+
+            return;
+        }
+
+        if (content_type == "application/x-cd-image") {
+            this.dvd_parser = new DVDParser (file);
+            this.dvd_parser.run.begin ();
+
+            return;
+        }
+
+        var uri = file.get_uri ();
+        try {
+            var gst_timeout = (ClockTime) (this.timeout * Gst.SECOND);
+
+            this.discoverer = new Discoverer (gst_timeout);
+        } catch (Error error) {
+            debug ("Failed to create a discoverer. Doing basic extraction.");
             this.extract_basic_information (file, null, null);
+
+            return;
         }
+
+        this.file_hash.set (uri, file);
+        this.discoverer.discovered.connect (on_done);
+        this.discoverer.start ();
+        this.discoverer.discover_uri_async (uri);
+        this.guesser = new GUPnPDLNA.ProfileGuesser (true, true);
     }
 
     private void on_done (DiscovererInfo info, GLib.Error err) {