[gthumb] browser: before loading a location cancel the previous load operation

[Paolo Bacchilega <paobac src gnome org>]

commit 1a782cafc9eebcdc9aaff8f715ea1d16308de5c0
Author: Paolo Bacchilega <paobac src gnome org>
Date:   Fri Dec 6 18:09:13 2019 +0100

    browser: before loading a location cancel the previous load operation

 gthumb/gth-browser.c | 84 ++++++++++++++++++++++++++++++++++------------------
 1 file changed, 56 insertions(+), 28 deletions(-)
---
diff --git a/gthumb/gth-browser.c b/gthumb/gth-browser.c
index 399d6c3d..542601ad 100644
--- a/gthumb/gth-browser.c
+++ b/gthumb/gth-browser.c
@@ -990,6 +990,10 @@ load_data_new (GthBrowser *browser,
        load_data->automatic = automatic;
        load_data->cancellable = g_cancellable_new ();
 
+       browser->priv->load_data_queue = g_list_prepend (browser->priv->load_data_queue, load_data);
+       if (gth_action_changes_folder (load_data->action))
+               browser->priv->last_folder_to_open = load_data;
+
        if (entry_point == NULL)
                return load_data;
 
@@ -1010,10 +1014,6 @@ load_data_new (GthBrowser *browser,
        g_object_unref (file);
        load_data->current = NULL;
 
-       browser->priv->load_data_queue = g_list_prepend (browser->priv->load_data_queue, load_data);
-       if (gth_action_changes_folder (load_data->action))
-               browser->priv->last_folder_to_open = load_data;
-
        return load_data;
 }
 
@@ -1120,6 +1120,14 @@ _gth_browser_remove_activity (GthBrowser *browser)
 }
 
 
+static gboolean
+load_data_is_still_relevant (LoadData *load_data)
+{
+       return ! gth_action_changes_folder (load_data->action)
+                   || (load_data == load_data->browser->priv->last_folder_to_open);
+}
+
+
 static void
 load_data_done (LoadData *load_data,
                GError   *error)
@@ -1148,12 +1156,16 @@ load_data_done (LoadData *load_data,
                       load_data->requested_folder->file,
                       TRUE);
 
-       if (g_error_matches (error, G_IO_ERROR, G_IO_ERROR_CANCELLED)) {
+       if (! load_data_is_still_relevant (load_data)
+               || g_error_matches (error, G_IO_ERROR, G_IO_ERROR_CANCELLED))
+       {
                g_error_free (error);
                return;
        }
 
-       if (load_data->automatic) {
+       if (gth_action_changes_folder (load_data->action)
+               && load_data->automatic)
+       {
                GFile *parent;
 
                parent = g_file_get_parent (load_data->requested_folder->file);
@@ -1171,7 +1183,8 @@ load_data_done (LoadData *load_data,
        }
 
        gth_browser_update_sensitivity (browser);
-       title = file_format (_("Could not load the position “%s”"), load_data->requested_folder->file);
+       title = file_format (_("Could not load the position “%s”"),
+                            load_data->requested_folder->file);
        _gth_browser_show_error (browser, title, error);
 
        g_free (title);
@@ -1188,6 +1201,15 @@ load_data_error (LoadData *load_data,
                                      NULL);
 
        load_data_done (load_data, error);
+       load_data_free (load_data);
+}
+
+
+static void
+load_data_cancelled (LoadData *load_data)
+{
+       load_data_done (load_data, g_error_new_literal (G_IO_ERROR, G_IO_ERROR_CANCELLED, ""));
+       load_data_free (load_data);
 }
 
 
@@ -1346,7 +1368,6 @@ requested_folder_attributes_ready_cb (GObject  *file_source,
 
        if (error != NULL) {
                load_data_error (load_data, error);
-               load_data_free (load_data);
                return;
        }
 
@@ -1457,11 +1478,8 @@ load_data_continue (LoadData *load_data,
        GtkTreePath *path;
        gboolean     changed_current_location;
 
-       if (gth_action_changes_folder (load_data->action)
-           && (load_data != browser->priv->last_folder_to_open))
-       {
-               load_data_done (load_data, g_error_new_literal (G_IO_ERROR, G_IO_ERROR_CANCELLED, ""));
-               load_data_free (load_data);
+       if (! load_data_is_still_relevant (load_data)) {
+               load_data_cancelled (load_data);
                return;
        }
 
@@ -1635,7 +1653,6 @@ metadata_ready_cb (GObject      *source_object,
        files = _g_query_metadata_finish (result, &error);
        if (error != NULL) {
                load_data_error (load_data, error);
-               load_data_free (load_data);
                return;
        }
 
@@ -1650,7 +1667,6 @@ load_data_ready (LoadData *load_data,
 {
        if (error != NULL) {
                load_data_error (load_data, error);
-               load_data_free (load_data);
        }
        else if (gth_action_changes_folder (load_data->action)
                 && _g_file_equal ((GFile *) load_data->current->data, load_data->requested_folder->file))
@@ -1684,25 +1700,27 @@ mount_volume_ready_cb (GObject      *source_object,
        LoadData *load_data = user_data;
        GError   *error = NULL;
 
-       _gth_browser_remove_activity (load_data->browser);
-
-       if (! g_file_mount_enclosing_volume_finish (G_FILE (source_object), result, &error)) {
-               char *title;
-
-               title = file_format (_("Could not load the position “%s”"), 
load_data->requested_folder->file);
-               _gth_browser_show_error (load_data->browser, title, error);
-               g_clear_error (&error);
-
-               g_free (title);
+       if (! g_file_mount_enclosing_volume_finish (G_FILE (source_object),
+                                                   result,
+                                                   &error))
+       {
+               load_data_done (load_data, error);
                load_data_free (load_data);
                return;
        }
 
+       gth_monitor_entry_points_changed (gth_main_get_default_monitor ());
+       _gth_browser_update_entry_point_list (load_data->browser);
+
        /* try to load again */
 
-       gth_monitor_entry_points_changed (gth_main_get_default_monitor());
+       if (! load_data_is_still_relevant (load_data)) {
+               load_data_cancelled (load_data);
+               return;
+       }
+
+       _gth_browser_remove_activity (load_data->browser);
 
-       _gth_browser_update_entry_point_list (load_data->browser);
        _gth_browser_load (load_data->browser,
                           load_data->requested_folder->file,
                           load_data->file_to_select,
@@ -1738,6 +1756,11 @@ _gth_browser_load (GthBrowser *browser,
        if (! automatic)
                _gth_browser_hide_infobar (browser);
 
+       if (gth_action_changes_folder (action) && (browser->priv->last_folder_to_open != NULL)) {
+               LoadData *last_load_data = (LoadData *) browser->priv->last_folder_to_open;
+               g_cancellable_cancel (last_load_data->cancellable);
+       }
+
        entry_point = gth_main_get_nearest_entry_point (location);
        load_data = load_data_new (browser,
                                   location,
@@ -1756,7 +1779,12 @@ _gth_browser_load (GthBrowser *browser,
                /* try to mount the enclosing volume */
 
                mount_op = gtk_mount_operation_new (GTK_WINDOW (browser));
-               g_file_mount_enclosing_volume (location, 0, mount_op, NULL, mount_volume_ready_cb, load_data);
+               g_file_mount_enclosing_volume (location,
+                                              0,
+                                              mount_op,
+                                              load_data->cancellable,
+                                              mount_volume_ready_cb,
+                                              load_data);
 
                g_object_unref (mount_op);