[gnome-software: 25/29] gs-plugin-loader: Call async shutdown functions on plugins

[Philip Withnall <pwithnall src gnome org>]

commit 22475f1697869c290d64f3803d902981067567f9
Author: Philip Withnall <pwithnall endlessos org>
Date:   Wed Nov 24 16:20:36 2021 +0000

    gs-plugin-loader: Call async shutdown functions on plugins
    
    Signed-off-by: Philip Withnall <pwithnall endlessos org>
    
    Helps: #1472

 lib/gs-plugin-loader.c | 74 ++++++++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 69 insertions(+), 5 deletions(-)
---
diff --git a/lib/gs-plugin-loader.c b/lib/gs-plugin-loader.c
index 260f5332a..4d31eb289 100644
--- a/lib/gs-plugin-loader.c
+++ b/lib/gs-plugin-loader.c
@@ -2485,6 +2485,71 @@ plugin_setup_cb (GObject      *source_object,
        g_main_context_wakeup (data->context);
 }
 
+typedef struct {
+       GsPluginLoader *plugin_loader;  /* (unowned) */
+       GMainContext *context;  /* (owned) */
+       guint n_pending;
+} ShutdownData;
+
+static void plugin_shutdown_cb (GObject      *source_object,
+                                GAsyncResult *result,
+                                gpointer      user_data);
+
+static void
+gs_plugin_loader_call_shutdown (GsPluginLoader *plugin_loader,
+                                GCancellable   *cancellable)
+{
+       ShutdownData shutdown_data;
+
+       shutdown_data.plugin_loader = plugin_loader;
+       shutdown_data.n_pending = 1;  /* incremented until all operations have been started */
+       shutdown_data.context = g_main_context_new ();
+
+       g_main_context_push_thread_default (shutdown_data.context);
+
+       for (guint i = 0; i < plugin_loader->plugins->len; i++) {
+               GsPlugin *plugin = GS_PLUGIN (plugin_loader->plugins->pdata[i]);
+
+               if (GS_PLUGIN_GET_CLASS (plugin)->shutdown_async != NULL) {
+                       GS_PLUGIN_GET_CLASS (plugin)->shutdown_async (plugin, cancellable,
+                                                                     plugin_shutdown_cb, &shutdown_data);
+                       shutdown_data.n_pending++;
+               }
+       }
+
+       /* Wait for setup to complete in all plugins. */
+       shutdown_data.n_pending--;
+
+       while (shutdown_data.n_pending > 0)
+               g_main_context_iteration (shutdown_data.context, TRUE);
+
+       g_main_context_pop_thread_default (shutdown_data.context);
+       g_clear_pointer (&shutdown_data.context, g_main_context_unref);
+}
+
+static void
+plugin_shutdown_cb (GObject      *source_object,
+                    GAsyncResult *result,
+                    gpointer      user_data)
+{
+       GsPlugin *plugin = GS_PLUGIN (source_object);
+       ShutdownData *data = user_data;
+       g_autoptr(GError) local_error = NULL;
+
+       g_assert (GS_PLUGIN_GET_CLASS (plugin)->shutdown_finish != NULL);
+
+       if (!GS_PLUGIN_GET_CLASS (plugin)->shutdown_finish (plugin, result, &local_error)) {
+               g_debug ("disabling %s as shutdown failed: %s",
+                        gs_plugin_get_name (plugin),
+                        local_error->message);
+               gs_plugin_set_enabled (plugin, FALSE);
+       }
+
+       /* Indicate this plugin has finished shutting down. */
+       data->n_pending--;
+       g_main_context_wakeup (data->context);
+}
+
 /**
  * gs_plugin_loader_setup_again:
  * @plugin_loader: a #GsPluginLoader
@@ -2499,6 +2564,9 @@ gs_plugin_loader_setup_again (GsPluginLoader *plugin_loader)
        gint64 begin_time_nsec G_GNUC_UNUSED = SYSPROF_CAPTURE_CURRENT_TIME;
 #endif
 
+       /* Shut down */
+       gs_plugin_loader_call_shutdown (plugin_loader, NULL);
+
        /* clear global cache */
        gs_plugin_loader_clear_caches (plugin_loader);
 
@@ -2859,11 +2927,7 @@ gs_plugin_loader_dispose (GObject *object)
 
        if (plugin_loader->plugins != NULL) {
                /* Shut down all the plugins first. */
-               for (guint i = 0; i < plugin_loader->plugins->len; i++) {
-                       GsPlugin *plugin = GS_PLUGIN (plugin_loader->plugins->pdata[i]);
-                       if (GS_PLUGIN_GET_CLASS (plugin)->shutdown_async != NULL)
-                               GS_PLUGIN_GET_CLASS (plugin)->shutdown_async (plugin, NULL, NULL, NULL);
-               }
+               gs_plugin_loader_call_shutdown (plugin_loader, NULL);
 
                g_clear_pointer (&plugin_loader->plugins, g_ptr_array_unref);
        }