[tracker-miners/wip/carlosg/cli-improvements: 9/30] tracker-extract: Remove files from persistence after cancellation

[Carlos Garnacho <carlosg src gnome org>]

commit 9583c198ab1fe3c39d4896cb50c16799c3b6d9f2
Author: Carlos Garnacho <carlosg gnome org>
Date:   Sun Aug 16 15:08:39 2020 +0200

    tracker-extract: Remove files from persistence after cancellation
    
    Move all cancellation handling closer to the TrackerExtractDecorator, so
    we can pull files off persistence handling, since cancellation shouldn't
    be considered an error on a future execution.
    
    We still should exit ASAP, though.

 src/tracker-extract/tracker-extract-decorator.c | 37 +++++++++++++++++++++++++
 src/tracker-extract/tracker-extract.c           | 34 -----------------------
 2 files changed, 37 insertions(+), 34 deletions(-)
---
diff --git a/src/tracker-extract/tracker-extract-decorator.c b/src/tracker-extract/tracker-extract-decorator.c
index 8a45cab17..804f19f49 100644
--- a/src/tracker-extract/tracker-extract-decorator.c
+++ b/src/tracker-extract/tracker-extract-decorator.c
@@ -40,6 +40,8 @@ struct _ExtractData {
        TrackerDecorator *decorator;
        TrackerDecoratorInfo *decorator_info;
        GFile *file;
+       GCancellable *cancellable;
+       gulong signal_id;
 };
 
 struct _TrackerExtractDecoratorPrivate {
@@ -162,6 +164,10 @@ get_metadata_cb (TrackerExtract *extract,
        tracker_extract_persistence_remove_file (priv->persistence, data->file);
        g_hash_table_remove (priv->recovery_files, tracker_decorator_info_get_url (data->decorator_info));
 
+       if (data->cancellable && data->signal_id != 0) {
+               g_cancellable_disconnect (data->cancellable, data->signal_id);
+       }
+
        if (error) {
                decorator_ignore_file (data->file, data->decorator);
                tracker_decorator_info_complete_error (data->decorator_info, error);
@@ -208,6 +214,7 @@ get_metadata_cb (TrackerExtract *extract,
 
        tracker_decorator_info_unref (data->decorator_info);
        g_object_unref (data->file);
+       g_object_unref (data->cancellable);
        g_free (data);
 }
 
@@ -231,6 +238,28 @@ decorator_get_recovery_file (TrackerExtractDecorator *decorator,
        return file;
 }
 
+static void
+task_cancellable_cancelled_cb (GCancellable *cancellable,
+                               ExtractData  *data)
+{
+       TrackerExtractDecoratorPrivate *priv;
+       gchar *uri;
+
+       /* Delete persistence file on cancellation, we don't want to interpret
+        * this as a failed operation.
+        */
+       priv = tracker_extract_decorator_get_instance_private (TRACKER_EXTRACT_DECORATOR (data->decorator));
+       tracker_extract_persistence_remove_file (priv->persistence, data->file);
+       uri = g_file_get_uri (data->file);
+
+       g_message ("Cancelled task for '%s' was currently being "
+                  "processed, _exit()ing immediately",
+                  uri);
+       g_free (uri);
+
+       _exit (0);
+}
+
 static void
 decorator_next_item_cb (TrackerDecorator *decorator,
                         GAsyncResult     *result,
@@ -281,6 +310,14 @@ decorator_next_item_cb (TrackerDecorator *decorator,
 
        tracker_extract_persistence_add_file (priv->persistence, data->file);
 
+       g_set_object (&data->cancellable, g_task_get_cancellable (task));
+
+       if (data->cancellable) {
+               data->signal_id = g_cancellable_connect (data->cancellable,
+                                                        G_CALLBACK (task_cancellable_cancelled_cb),
+                                                        data, NULL);
+       }
+
        tracker_extract_file (priv->extractor,
                              tracker_decorator_info_get_url (info),
                              tracker_decorator_info_get_mimetype (info),
diff --git a/src/tracker-extract/tracker-extract.c b/src/tracker-extract/tracker-extract.c
index 56107f195..12cb00b4f 100644
--- a/src/tracker-extract/tracker-extract.c
+++ b/src/tracker-extract/tracker-extract.c
@@ -89,7 +89,6 @@ typedef struct {
        TrackerExtractMetadataFunc func;
        GModule *module;
 
-       guint signal_id;
        guint timeout_id;
        guint success : 1;
 } TrackerExtractTask;
@@ -324,29 +323,6 @@ get_file_metadata (TrackerExtractTask  *task,
        return task->success;
 }
 
-/* This function is called on the thread calling g_cancellable_cancel() */
-static void
-task_cancellable_cancelled_cb (GCancellable       *cancellable,
-                               TrackerExtractTask *task)
-{
-       TrackerExtractPrivate *priv;
-       TrackerExtract *extract;
-
-       extract = task->extract;
-       priv = TRACKER_EXTRACT_GET_PRIVATE (extract);
-
-       g_mutex_lock (&priv->task_mutex);
-
-       if (g_list_find (priv->running_tasks, task)) {
-               g_message ("Cancelled task for '%s' was currently being "
-                          "processed, _exit()ing immediately",
-                          task->file);
-               _exit (0);
-       }
-
-       g_mutex_unlock (&priv->task_mutex);
-}
-
 static gboolean
 task_deadline_cb (gpointer user_data)
 {
@@ -414,22 +390,12 @@ extract_task_new (TrackerExtract *extract,
                        g_source_attach (source, g_task_get_context (G_TASK (task->res)));
        }
 
-       if (task->cancellable) {
-               task->signal_id = g_cancellable_connect (cancellable,
-                                                        G_CALLBACK (task_cancellable_cancelled_cb),
-                                                        task, NULL);
-       }
-
        return task;
 }
 
 static void
 extract_task_free (TrackerExtractTask *task)
 {
-       if (task->cancellable && task->signal_id != 0) {
-               g_cancellable_disconnect (task->cancellable, task->signal_id);
-       }
-
        notify_task_finish (task, task->success);
 
        if (task->timeout_id)