[pango/tab-speedup: 1/4] Add pango_tab_array_sort

[Matthias Clasen <matthiasc src gnome org>]

commit 0a1c31901fbf0db9e98b02ad3ba02681f1c31774
Author: Matthias Clasen <mclasen redhat com>
Date:   Wed Dec 1 23:03:28 2021 -0500

    Add pango_tab_array_sort
    
    A utility function to ensure tab stops are in
    increasing order.

 pango/pango-tabs.c | 25 +++++++++++++++++++++++++
 pango/pango-tabs.h |  3 +++
 2 files changed, 28 insertions(+)
---
diff --git a/pango/pango-tabs.c b/pango/pango-tabs.c
index 27ae3be8..0665161c 100644
--- a/pango/pango-tabs.c
+++ b/pango/pango-tabs.c
@@ -576,3 +576,28 @@ pango_tab_array_get_decimal_point (PangoTabArray *tab_array,
 
   return tab_array->tabs[tab_index].decimal_point;
 }
+
+static int
+compare_tabs (const void *p1, const void *p2)
+{
+  const PangoTab *t1 = p1;
+  const PangoTab *t2 = p2;
+
+  return t1->location - t2->location;
+}
+
+/**
+ * pango_tab_array_sort:
+ * @tab_array: a `PangoTabArray`
+ *
+ * Utility function to ensure that the tab stops are in increasing order.
+ *
+ * Since: 1.50
+ */
+void
+pango_tab_array_sort (PangoTabArray *tab_array)
+{
+  g_return_if_fail (tab_array != NULL);
+
+  qsort (tab_array->tabs, tab_array->size, sizeof (PangoTab), compare_tabs);
+}
diff --git a/pango/pango-tabs.h b/pango/pango-tabs.h
index 0792a36a..8ca94fdb 100644
--- a/pango/pango-tabs.h
+++ b/pango/pango-tabs.h
@@ -106,6 +106,9 @@ PANGO_AVAILABLE_IN_1_50
 gunichar        pango_tab_array_get_decimal_point   (PangoTabArray *tab_array,
                                                      int            tab_index);
 
+PANGO_AVAILABLE_IN_1_50
+void            pango_tab_array_sort                (PangoTabArray *tab_array);
+
 G_DEFINE_AUTOPTR_CLEANUP_FUNC(PangoTabArray, pango_tab_array_free)
 
 G_END_DECLS