[gnome-software/wip/iainl/ubuntu-xenial] Refresh the apt database

[William Hua <williamhua src gnome org>]

commit 6279907c7c23d0ba004bd1537c263121cdf6a259
Author: William Hua <william hua canonical com>
Date:   Wed Apr 13 18:11:20 2016 -0400

    Refresh the apt database

 src/plugins/gs-plugin-apt.cc |   91 ++++++++++++++++++++++++++----------------
 1 files changed, 57 insertions(+), 34 deletions(-)
---
diff --git a/src/plugins/gs-plugin-apt.cc b/src/plugins/gs-plugin-apt.cc
index 7f78811..012a23b 100644
--- a/src/plugins/gs-plugin-apt.cc
+++ b/src/plugins/gs-plugin-apt.cc
@@ -80,7 +80,8 @@ typedef struct {
 #include "ubuntu-unity-launcher-proxy.h"
 
 struct GsPluginPrivate {
-       gsize            loaded;
+       GMutex           mutex;
+       gboolean         loaded;
        GHashTable      *package_info;
        GHashTable      *installed_files;
        GList           *installed_packages;
@@ -149,6 +150,8 @@ gs_plugin_initialize (GsPlugin *plugin)
                                                            g_free,
                                                            g_free);
 
+       g_mutex_init (&plugin->priv->mutex);
+
        pkgInitConfig (*_config);
        pkgInitSystem (*_config, _system);
 }
@@ -156,10 +159,14 @@ gs_plugin_initialize (GsPlugin *plugin)
 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);
+       g_mutex_lock (&plugin->priv->mutex);
+       plugin->priv->loaded = FALSE;
+       g_clear_pointer (&plugin->priv->package_info, g_hash_table_unref);
+       g_clear_pointer (&plugin->priv->installed_files, g_hash_table_unref);
+       g_clear_pointer (&plugin->priv->installed_packages, g_list_free);
+       g_clear_pointer (&plugin->priv->updatable_packages, g_list_free);
+       g_mutex_unlock (&plugin->priv->mutex);
+       g_mutex_clear (&plugin->priv->mutex);
 }
 
 
@@ -412,9 +419,14 @@ load_apt_db (GsPlugin *plugin, GError **error)
        pkgSourceList *list;
        pkgPolicy *policy;
        pkgCacheFile cachefile;
-       pkgCache *cache = cachefile.GetPkgCache();
+       pkgCache *cache;
        pkgCache::PkgIterator P;
+       g_autoptr(GMutexLocker) locker = g_mutex_locker_new (&plugin->priv->mutex);
+
+       if (plugin->priv->loaded)
+               return TRUE;
 
+       cache = cachefile.GetPkgCache();
        list = cachefile.GetSourceList();
        policy = cachefile.GetPolicy();
        if (cache == NULL || _error->PendingError()) {
@@ -437,10 +449,23 @@ load_apt_db (GsPlugin *plugin, GError **error)
        /* load filename -> package map into plugin->priv->installed_files */
        look_for_files (plugin);
 
+       plugin->priv->loaded = TRUE;
        return TRUE;
 }
 
 static void
+unload_apt_db (GsPlugin *plugin)
+{
+       g_autoptr(GMutexLocker) locker = g_mutex_locker_new (&plugin->priv->mutex);
+
+       plugin->priv->loaded = FALSE;
+       g_hash_table_remove_all (plugin->priv->package_info);
+       g_hash_table_remove_all (plugin->priv->installed_files);
+       g_clear_pointer (&plugin->priv->installed_packages, g_list_free);
+       g_clear_pointer (&plugin->priv->updatable_packages, g_list_free);
+}
+
+static void
 get_changelog (GsPlugin *plugin, GsApp *app)
 {
        guint i;
@@ -546,16 +571,12 @@ gs_plugin_refine (GsPlugin *plugin,
        GsApp *app;
        PackageInfo *info;
        const gchar *tmp;
+       g_autoptr(GMutexLocker) locker = NULL;
 
-       /* Load database once */
-       if (g_once_init_enter (&plugin->priv->loaded)) {
-               gboolean ret;
+       if (!load_apt_db (plugin, error))
+               return FALSE;
 
-               ret = load_apt_db (plugin, error);
-               g_once_init_leave (&plugin->priv->loaded, TRUE);
-               if (!ret)
-                       return FALSE;
-       }
+       locker = g_mutex_locker_new (&plugin->priv->mutex);
 
        for (link = *list; link; link = link->next) {
                app = (GsApp *) link->data;
@@ -665,17 +686,12 @@ gs_plugin_add_installed (GsPlugin *plugin,
                         GError **error)
 {
        GList *link;
+       g_autoptr(GMutexLocker) locker = NULL;
 
-       /* Load database once */
-       if (g_once_init_enter (&plugin->priv->loaded)) {
-               gboolean ret;
-
-               ret = load_apt_db (plugin, error);
-               g_once_init_leave (&plugin->priv->loaded, TRUE);
-               if (!ret)
-                       return FALSE;
-       }
+       if (!load_apt_db (plugin, error))
+               return FALSE;
 
+       locker = g_mutex_locker_new (&plugin->priv->mutex);
 
        for (link = plugin->priv->installed_packages; link; link = link->next) {
                PackageInfo *info = (PackageInfo *) link->data;
@@ -962,7 +978,12 @@ gs_plugin_refresh (GsPlugin *plugin,
        if ((flags & GS_PLUGIN_REFRESH_FLAGS_UPDATES) == 0)
                return TRUE;
 
-       return aptd_transaction (plugin, "UpdateCache", NULL, NULL, NULL, error);
+       if (!aptd_transaction (plugin, "UpdateCache", NULL, NULL, NULL, error))
+               return FALSE;
+
+       unload_apt_db (plugin);
+
+       return TRUE;
 }
 
 gboolean
@@ -972,16 +993,12 @@ gs_plugin_add_updates (GsPlugin *plugin,
                        GError **error)
 {
        GList *link;
+       g_autoptr(GMutexLocker) locker = NULL;
 
-       /* Load database once */
-       if (g_once_init_enter (&plugin->priv->loaded)) {
-               gboolean ret;
+       if (!load_apt_db (plugin, error))
+               return FALSE;
 
-               ret = load_apt_db (plugin, error);
-               g_once_init_leave (&plugin->priv->loaded, TRUE);
-               if (!ret)
-                       return FALSE;
-       }
+       locker = g_mutex_locker_new (&plugin->priv->mutex);
 
        for (link = plugin->priv->updatable_packages; link; link = link->next) {
                PackageInfo *info = (PackageInfo *) link->data;
@@ -1037,6 +1054,8 @@ gs_plugin_update (GsPlugin      *plugin,
        if (aptd_transaction (plugin, "UpgradeSystem", NULL, apps, g_variant_new_parsed ("(true,)"), error)) {
                set_list_state (apps, AS_APP_STATE_INSTALLED);
 
+               unload_apt_db (plugin);
+
                return TRUE;
        } else {
                set_list_state (apps, AS_APP_STATE_UPDATABLE_LIVE);
@@ -1077,6 +1096,8 @@ gs_plugin_update_app (GsPlugin *plugin,
 
                        for (i = 0; i < apps->len; i++)
                                gs_app_set_state (GS_APP (g_ptr_array_index (apps, i)), 
AS_APP_STATE_INSTALLED);
+
+                       unload_apt_db (plugin);
                } else {
                        gs_app_set_state (app, AS_APP_STATE_UPDATABLE_LIVE);
 
@@ -1088,9 +1109,11 @@ gs_plugin_update_app (GsPlugin *plugin,
        } else if (app_is_ours (app)) {
                gs_app_set_state (app, AS_APP_STATE_INSTALLING);
 
-               if (aptd_transaction (plugin, "UpgradePackages", app, NULL, NULL, error))
+               if (aptd_transaction (plugin, "UpgradePackages", app, NULL, NULL, error)) {
                        gs_app_set_state (app, AS_APP_STATE_INSTALLED);
-               else {
+
+                       unload_apt_db (plugin);
+               } else {
                        gs_app_set_state (app, AS_APP_STATE_UPDATABLE_LIVE);
 
                        return FALSE;