[glib] GThreadPool: Add some queue manipulation api

[Matthias Clasen <matthiasc src gnome org>]

commit 9486f697bb3ed3b02fa2c82f50662fde7d77267e
Author: Matthias Clasen <mclasen redhat com>
Date:   Mon Jun 29 08:19:31 2015 -0700

    GThreadPool: Add some queue manipulation api
    
    GTask has a need for an api that boosts an unprocessed
    item to the front of the queue, so add one.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=751160

 docs/reference/glib/glib-sections.txt |    1 +
 glib/gthreadpool.c                    |   30 ++++++++++++++++++++++++++++++
 glib/gthreadpool.h                    |    4 ++++
 3 files changed, 35 insertions(+), 0 deletions(-)
---
diff --git a/docs/reference/glib/glib-sections.txt b/docs/reference/glib/glib-sections.txt
index 5e783e8..880dab6 100644
--- a/docs/reference/glib/glib-sections.txt
+++ b/docs/reference/glib/glib-sections.txt
@@ -827,6 +827,7 @@ g_thread_pool_stop_unused_threads
 g_thread_pool_set_sort_function
 g_thread_pool_set_max_idle_time
 g_thread_pool_get_max_idle_time
+g_thread_pool_move_to_front
 </SECTION>
 
 <SECTION>
diff --git a/glib/gthreadpool.c b/glib/gthreadpool.c
index dad424d..725f627 100644
--- a/glib/gthreadpool.c
+++ b/glib/gthreadpool.c
@@ -963,6 +963,36 @@ g_thread_pool_set_sort_function (GThreadPool      *pool,
 }
 
 /**
+ * g_thread_pool_move_to_front:
+ * @pool: a #GThreadPool
+ * @data: an unprocessed item in the pool
+ *
+ * Moves the item to the front of the queue of unprocessed
+ * items, so that it will be processed next.
+ *
+ * Returns: %TRUE if the item was found and moved
+ *
+ * Since: 2.46
+ */
+gboolean
+g_thread_pool_move_to_front (GThreadPool *pool,
+                             gpointer     data)
+{
+  GRealThreadPool *real = (GRealThreadPool*) pool;
+  gboolean found;
+
+  g_async_queue_lock (real->queue);
+
+  found = g_async_queue_remove_unlocked (real->queue, data);
+  if (found)
+    g_async_queue_push_front_unlocked (real->queue, data);
+
+  g_async_queue_unlock (real->queue);
+
+  return found;
+}
+
+/**
  * g_thread_pool_set_max_idle_time:
  * @interval: the maximum @interval (in milliseconds)
  *     a thread can be idle
diff --git a/glib/gthreadpool.h b/glib/gthreadpool.h
index b46987d..95c10a0 100644
--- a/glib/gthreadpool.h
+++ b/glib/gthreadpool.h
@@ -65,6 +65,10 @@ GLIB_AVAILABLE_IN_ALL
 void            g_thread_pool_set_sort_function (GThreadPool      *pool,
                                                  GCompareDataFunc  func,
                                                  gpointer          user_data);
+GLIB_AVAILABLE_IN_2_46
+gboolean        g_thread_pool_move_to_front     (GThreadPool      *pool,
+                                                 gpointer          data);
+
 GLIB_AVAILABLE_IN_ALL
 gboolean        g_thread_pool_set_max_threads   (GThreadPool     *pool,
                                                  gint             max_threads,