From 705de2e71488998329302e931004e75cd9a7451e Mon Sep 17 00:00:00 2001
From: Aaron Andersen <aaron@fosslib.net>
Date: Mon, 10 Nov 2025 10:06:54 -0500
Subject: [PATCH] glog: guard NO_COLOR environment variable check with a GOnce
 for performance reasons

---
 glib/gmessages.c | 21 +++++++++++++--------
 1 file changed, 13 insertions(+), 8 deletions(-)

diff --git a/glib/gmessages.c b/glib/gmessages.c
index 01555356d..47367d601 100644
--- a/glib/gmessages.c
+++ b/glib/gmessages.c
@@ -2712,10 +2712,10 @@ g_log_writer_standard_streams (GLogLevelFlags   log_level,
                                gsize            n_fields,
                                gpointer         user_data)
 {
-  gboolean use_color;
+  static gboolean use_color;
+  static size_t use_color_init = 0;
   FILE *stream;
   char *out;
-  const char *no_color_env;
 
   g_return_val_if_fail (fields != NULL, G_LOG_WRITER_UNHANDLED);
   g_return_val_if_fail (n_fields > 0, G_LOG_WRITER_UNHANDLED);
@@ -2724,12 +2724,17 @@ g_log_writer_standard_streams (GLogLevelFlags   log_level,
   if (!stream || fileno (stream) < 0)
     return G_LOG_WRITER_UNHANDLED;
 
-  /* Honor NO_COLOR environment variable (https://no-color.org) */
-  no_color_env = g_getenv ("NO_COLOR");
-  if (no_color_env && *no_color_env != '\0')
-    use_color = FALSE;
-  else
-    use_color = g_log_writer_supports_color (fileno (stream));
+  if (g_once_init_enter (&use_color_init))
+    {
+      /* Honor NO_COLOR environment variable (https://no-color.org) */
+      const char *no_color_env = g_getenv ("NO_COLOR");
+      if (no_color_env && *no_color_env != '\0')
+        use_color = FALSE;
+      else
+        use_color = g_log_writer_supports_color (fileno (stream));
+
+      g_once_init_leave (&use_color_init, 1);
+    }
 
   out = log_writer_format_fields_utf8 (log_level, fields, n_fields, use_color, TRUE);