From 7b8503c2516f549dd6b4789805acc6d6a596d15f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=D0=A0=D1=83=D1=81=D0=BB=D0=B0=D0=BD=20=D0=98=D0=B6=D0=B1?=
 =?UTF-8?q?=D1=83=D0=BB=D0=B0=D1=82=D0=BE=D0=B2?= <address@hidden>
Date: Tue, 3 Jul 2018 23:07:55 +0000
Subject: [PATCH 1/2] Use GetUserDefaultUILanguage instead of GetThreadLocale

GetThreadLocale() returns the user-chosen "Format" language,
not the UI language of the operating system. Use the
GetUserDefaultUILanguage() for that instead, when the category
being queried for the default locale name is LC_MESSAGES.
---
 lib/localename.c | 20 ++++++++++++++++++--
 lib/localename.h | 17 +++++++++++++++++
 lib/setlocale.c  |  6 +++---
 3 files changed, 38 insertions(+), 5 deletions(-)

diff --git a/lib/localename.c b/lib/localename.c
index c9415c9..d6120f4 100644
--- a/lib/localename.c
+++ b/lib/localename.c
@@ -2888,7 +2888,7 @@ gl_locale_name_environ (int category, const char *categoryname)
 }
 
 const char *
-gl_locale_name_default (void)
+gl_locale_name_default_for_category (int category)
 {
   /* POSIX:2001 says:
      "All implementations shall define a locale as the default locale, to be
@@ -2974,6 +2974,16 @@ gl_locale_name_default (void)
 # endif
 
 # if defined WINDOWS_NATIVE || defined __CYGWIN__ /* Native Windows or Cygwin */
+  if (category == LC_MESSAGES)
+  {
+    LANGID langid;
+
+    /* Use native Windows API UI language ID.  */
+    langid = GetUserDefaultUILanguage ();
+
+    return gl_locale_name_from_win32_LANGID (langid);
+  }
+  else
   {
     LCID lcid;
 
@@ -2986,6 +2996,12 @@ gl_locale_name_default (void)
 #endif
 }
 
+const char *
+gl_locale_name_default ()
+{
+  return gl_locale_name_default_for_category (LC_CTYPE);
+}
+
 /* Determine the current locale's name, and canonicalize it into XPG syntax
      address@hidden
    The codeset part in the result is not reliable; the locale_charset()
@@ -3005,5 +3021,5 @@ gl_locale_name (int category, const char *categoryname)
   if (retval != NULL)
     return retval;
 
-  return gl_locale_name_default ();
+  return gl_locale_name_default_for_category (LC_CTYPE);
 }
diff --git a/lib/localename.h b/lib/localename.h
index a7c0369..e68c244 100644
--- a/lib/localename.h
+++ b/lib/localename.h
@@ -92,6 +92,23 @@ extern const char * gl_locale_name_default (void)
 #endif
   ;
 
+/* Determine the default locale's name for a given category.
+   This is the current locale's name for a given category,
+   if not specified by uselocale() calls, by setlocale() calls, or by
+   environment variables.  This locale name is usually determined by systems
+   settings that the user can manipulate through a GUI.
+
+   Unlike gl_locale_name_default(), it returns correct locale for LC_MESSAGES
+   when running on Windows.
+
+   The result must not be freed; it is statically allocated.  */
+extern const char * gl_locale_name_default_for_category (int category)
+#if !(HAVE_CFLOCALECOPYCURRENT || HAVE_CFPREFERENCESCOPYAPPVALUE \
+      || defined _WIN32 || defined __WIN32__ || defined __CYGWIN__)
+  _GL_ATTRIBUTE_CONST
+#endif
+  ;
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/lib/setlocale.c b/lib/setlocale.c
index 1ac3f4d..13fa545 100644
--- a/lib/setlocale.c
+++ b/lib/setlocale.c
@@ -848,7 +848,7 @@ rpl_setlocale (int category, const char *locale)
           base_name =
             gl_locale_name_environ (LC_CTYPE, category_to_name (LC_CTYPE));
           if (base_name == NULL)
-            base_name = gl_locale_name_default ();
+            base_name = gl_locale_name_default_for_category (LC_CTYPE);
 
           if (setlocale_unixlike (LC_ALL, base_name) == NULL)
             goto fail;
@@ -868,7 +868,7 @@ rpl_setlocale (int category, const char *locale)
 
               name = gl_locale_name_environ (cat, category_to_name (cat));
               if (name == NULL)
-                name = gl_locale_name_default ();
+                name = gl_locale_name_default_for_category (cat);
 
               /* If name is the same as base_name, it has already been set
                  through the setlocale call before the loop.  */
@@ -896,7 +896,7 @@ rpl_setlocale (int category, const char *locale)
           const char *name =
             gl_locale_name_environ (category, category_to_name (category));
           if (name == NULL)
-            name = gl_locale_name_default ();
+            name = gl_locale_name_default_for_category (category);
 
           return setlocale_single (category, name);
         }
-- 
2.4.0