[gtksourceview] lines: use fast integer to string conversion

[Christian Hergert <chergert src gnome org>]

commit bb42f80f542e50111e6b9693992f9f3f8655e422
Author: Christian Hergert <chergert redhat com>
Date:   Thu Apr 18 14:31:18 2019 -0700

    lines: use fast integer to string conversion
    
    In the vast majority of cases, we can create a fast path here that uses
    internal strings of the library to speed up line number generation instead
    of relying on g_snprintf()/gnulib/etc.
    
    The speedup is more noticable on large displays such as HiDPI.

 gtksourceview/gtksourcegutterrendererlines.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)
---
diff --git a/gtksourceview/gtksourcegutterrendererlines.c b/gtksourceview/gtksourcegutterrendererlines.c
index 20689804..8df6c7d0 100644
--- a/gtksourceview/gtksourcegutterrendererlines.c
+++ b/gtksourceview/gtksourcegutterrendererlines.c
@@ -23,6 +23,7 @@
 #endif
 
 #include "gtksourcegutterrendererlines.h"
+#include "gtksourceutils-private.h"
 #include "gtksourceview.h"
 
 struct _GtkSourceGutterRendererLinesPrivate
@@ -216,6 +217,7 @@ gutter_renderer_query_data (GtkSourceGutterRenderer      *renderer,
 {
        GtkSourceGutterRendererLines *lines = GTK_SOURCE_GUTTER_RENDERER_LINES (renderer);
        gchar text[24];
+       const gchar *textptr = text;
        gint line;
        gint len;
        gboolean current_line;
@@ -225,17 +227,17 @@ gutter_renderer_query_data (GtkSourceGutterRenderer      *renderer,
        current_line = (state & GTK_SOURCE_GUTTER_RENDERER_STATE_CURSOR) &&
                       lines->priv->cursor_visible;
 
-       if (current_line)
+       if G_LIKELY (!current_line)
        {
-               len = g_snprintf (text, sizeof text, "<b>%d</b>", line);
+               len = _gtk_source_utils_int_to_string (line, &textptr, text);
        }
        else
        {
-               len = g_snprintf (text, sizeof text, "%d", line);
+               len = g_snprintf (text, sizeof text, "<b>%d</b>", line);
        }
 
        gtk_source_gutter_renderer_text_set_markup (GTK_SOURCE_GUTTER_RENDERER_TEXT (renderer),
-                                                   text,
+                                                   textptr,
                                                    len);
 }