[gnome-software/wip/temp/ubuntu-xenial-rebased: 224/326] apt: Read lists of installed files from dpkg directly

[Iain Lane <iainl src gnome org>]

commit 4bd0eefd0689a5eed8325336db2658848de517de
Author: Iain Lane <iain orangesquash org uk>
Date:   Wed Apr 13 14:40:46 2016 +0100

    apt: Read lists of installed files from dpkg directly
    
    This is needed so that we can map from IDs, such as those from
    AppStream, back to packages.

 src/plugins/gs-plugin-apt.cc |  215 +++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 213 insertions(+), 2 deletions(-)
---
diff --git a/src/plugins/gs-plugin-apt.cc b/src/plugins/gs-plugin-apt.cc
index f9c50d4..1eccd43 100644
--- a/src/plugins/gs-plugin-apt.cc
+++ b/src/plugins/gs-plugin-apt.cc
@@ -46,6 +46,24 @@
 
 #define LICENSE_URL "http://www.ubuntu.com/about/about-ubuntu/licensing";
 
+#define INFO_DIR "/var/lib/dpkg/info"
+
+typedef struct
+{
+       GMutex pending_mutex;
+       GCond pending_cond;
+
+       GMutex dispatched_mutex;
+       GCond dispatched_cond;
+
+       GMutex hashtable_mutex;
+
+       guint still_to_read;
+       guint dispatched_reads;
+
+       GsPlugin *plugin;
+} ReadListData;
+
 typedef struct {
        gchar           *name;
        gchar           *section;
@@ -64,6 +82,7 @@ typedef struct {
 struct GsPluginPrivate {
        gsize            loaded;
        GHashTable      *package_info;
+       GHashTable      *installed_files;
        GList           *installed_packages;
        GList           *updatable_packages;
 };
@@ -125,6 +144,11 @@ gs_plugin_initialize (GsPlugin *plugin)
                                                            NULL,
                                                            free_package_info);
 
+       plugin->priv->installed_files = g_hash_table_new_full (g_str_hash,
+                                                           g_str_equal,
+                                                           g_free,
+                                                           g_free);
+
        pkgInitConfig (*_config);
        pkgInitSystem (*_config, _system);
 }
@@ -133,10 +157,158 @@ void
 gs_plugin_destroy (GsPlugin *plugin)
 {
        g_hash_table_unref (plugin->priv->package_info);
+       g_hash_table_unref (plugin->priv->installed_files);
        g_list_free (plugin->priv->installed_packages);
        g_list_free (plugin->priv->updatable_packages);
 }
 
+
+static void
+read_list_file_cb (GObject *object,
+                  GAsyncResult *res,
+                  gpointer user_data)
+{
+       g_autoptr(GFileInputStream) stream = NULL;
+       g_autoptr(GFile) file = NULL;
+       ReadListData *data;
+       g_autofree gchar *buffer = NULL;
+       g_autofree gchar *filename = NULL;
+       g_autoptr(GFileInfo) info = NULL;
+       g_auto(GStrv) file_lines = NULL;
+       g_auto(GStrv) file_components = NULL;
+       gchar *line;
+
+       file = G_FILE (object);
+       data = (ReadListData *) user_data;
+       stream = g_file_read_finish (file, res, NULL);
+
+       info = g_file_input_stream_query_info (stream,
+                                              G_FILE_ATTRIBUTE_STANDARD_SIZE,
+                                              NULL,
+                                              NULL);
+
+       if (!info)
+               return;
+
+       if (!g_file_info_has_attribute (info, G_FILE_ATTRIBUTE_STANDARD_SIZE))
+               return;
+
+       buffer = (gchar *) g_malloc0 (g_file_info_get_size (info) + 1);
+
+       if (!g_input_stream_read_all (G_INPUT_STREAM (stream),
+                                     buffer,
+                                     g_file_info_get_size (info),
+                                     NULL,
+                                     NULL,
+                                     NULL))
+               return;
+
+       g_input_stream_close (G_INPUT_STREAM (stream), NULL, NULL);
+
+       file_lines = g_strsplit (buffer, "\n", -1);
+
+       filename = g_file_get_basename (file);
+       file_components = g_strsplit (filename, ".", 2);
+
+       for (int i = 0; file_lines[i]; ++i)
+               if (g_str_has_suffix (file_lines[i], ".desktop") ||
+                   g_str_has_suffix (file_lines[i], ".metainfo.xml") ||
+                   g_str_has_suffix (file_lines[i], ".appdata.xml"))
+               {
+                       g_mutex_lock (&data->hashtable_mutex);
+                       /* filename -> package */
+                       g_hash_table_insert (data->plugin->priv->installed_files,
+                                            g_strdup (file_lines[i]),
+                                            g_strdup (file_components[0]));
+                       g_mutex_unlock (&data->hashtable_mutex);
+               }
+
+       g_mutex_lock (&data->dispatched_mutex);
+       (data->dispatched_reads)--;
+       g_cond_signal(&data->dispatched_cond);
+       g_mutex_unlock(&data->dispatched_mutex);
+
+       g_mutex_lock (&data->pending_mutex);
+       (data->still_to_read)--;
+       g_cond_signal (&data->pending_cond);
+       g_mutex_unlock (&data->pending_mutex);
+}
+
+static void
+read_list_file (GList *files,
+               ReadListData *data)
+{
+       GFile *gfile;
+       GList *files_iter;
+
+       for (files_iter = files; files_iter; files_iter = files_iter->next)
+       {
+               /* freed in read_list_file_cb */
+               gfile = g_file_new_for_path ((gchar *) files_iter->data);
+
+               g_mutex_lock (&data->dispatched_mutex);
+               g_file_read_async (gfile,
+                               G_PRIORITY_DEFAULT,
+                               NULL,
+                               read_list_file_cb,
+                               data);
+
+               (data->dispatched_reads)++;
+
+               while (data->dispatched_reads >= 500)
+                       g_cond_wait (&data->dispatched_cond, &data->dispatched_mutex);
+
+               g_mutex_unlock (&data->dispatched_mutex);
+       }
+}
+
+static void
+look_for_files (GsPlugin *plugin)
+{
+
+       ReadListData data;
+       GList *files = NULL;
+
+       data.still_to_read = 0;
+       data.dispatched_reads = 0;
+       g_cond_init (&data.pending_cond);
+       g_mutex_init (&data.pending_mutex);
+       g_cond_init (&data.dispatched_cond);
+       g_mutex_init (&data.dispatched_mutex);
+       g_mutex_init (&data.hashtable_mutex);
+       data.plugin = plugin;
+
+       g_autoptr (GDir) dir = NULL;
+       const gchar *file;
+
+       dir = g_dir_open (INFO_DIR, 0, NULL);
+
+       while (file = g_dir_read_name (dir))
+               if (g_str_has_suffix (file, ".list") &&
+                  /* app-install-data contains loads of .desktop files, but they aren't installed by it */
+                  (!g_strcmp0 (file, "app-install-data.list") == 0))
+               {
+                       files = g_list_append (files, g_build_filename (INFO_DIR, file, NULL));
+                       data.still_to_read++;
+               }
+
+       read_list_file (files, &data);
+
+       /* Wait until all the reads are done */
+       g_mutex_lock (&data.pending_mutex);
+       while (data.still_to_read > 0)
+               g_cond_wait (&data.pending_cond, &data.pending_mutex);
+       g_mutex_unlock (&data.pending_mutex);
+
+       g_mutex_clear (&data.pending_mutex);
+       g_cond_clear (&data.pending_cond);
+       g_mutex_clear (&data.dispatched_mutex);
+       g_cond_clear (&data.dispatched_cond);
+       g_mutex_clear (&data.hashtable_mutex);
+
+       g_list_free_full (files, g_free);
+}
+
 static gboolean
 version_newer (const gchar *v0, const gchar *v1)
 {
@@ -262,6 +434,9 @@ load_apt_db (GsPlugin *plugin, GError **error)
                        return FALSE;
        }
 
+       /* load filename -> package map into plugin->priv->installed_files */
+       look_for_files (plugin);
+
        return TRUE;
 }
 
@@ -356,6 +531,9 @@ gs_plugin_refine (GsPlugin *plugin,
                  GError **error)
 {
        GList *link;
+       GsApp *app;
+       PackageInfo *info;
+       const gchar *tmp;
 
        /* Load database once */
        if (g_once_init_enter (&plugin->priv->loaded)) {
@@ -368,8 +546,7 @@ gs_plugin_refine (GsPlugin *plugin,
        }
 
        for (link = *list; link; link = link->next) {
-               GsApp *app = (GsApp *) link->data;
-               PackageInfo *info;
+               app = (GsApp *) link->data;
 
                if (gs_app_get_source_default (app) == NULL)
                        continue;
@@ -411,6 +588,40 @@ gs_plugin_refine (GsPlugin *plugin,
                }
        }
 
+       for (link = *list; link != NULL; link = link->next) {
+               g_autofree gchar *fn = NULL;
+               gchar *package = NULL;
+               app = GS_APP (link->data);
+               if (gs_app_get_source_id_default (app) != NULL)
+                       continue;
+               tmp = gs_app_get_id (app);
+               if (tmp == NULL)
+                       continue;
+               switch (gs_app_get_kind (app)) {
+               case AS_APP_KIND_DESKTOP:
+                       fn = g_strdup_printf ("/usr/share/applications/%s", tmp);
+                       break;
+               case AS_APP_KIND_ADDON:
+                       fn = g_strdup_printf ("/usr/share/appdata/%s.metainfo.xml", tmp);
+                       break;
+               default:
+                       break;
+               }
+               if (fn == NULL)
+                       continue;
+               if (!g_file_test (fn, G_FILE_TEST_EXISTS)) {
+                       g_debug ("ignoring %s as does not exist", fn);
+                       continue;
+               }
+               package = (gchar *) g_hash_table_lookup (plugin->priv->installed_files,
+                                                        fn);
+               if (package == NULL)
+                       continue;
+               g_debug ("%s => %s", gs_app_get_id (app), package);
+               gs_app_add_source (app, package);
+               gs_app_set_management_plugin (app, "apt");
+       }
+
        return TRUE;
 }