From 713e7b2c547731577decd78204b94bfdac884e50 Mon Sep 17 00:00:00 2001
From: Augustin Cavalier <waddlesplash@gmail.com>
Date: Wed, 7 Jan 2026 16:27:46 -0500
Subject: [PATCH] locale: Implement getlocalename_l.

Specified in POSIX-2024.

GNUlib currently has a nasty Haiku-specific hack to implement
equivalent functionality; after this it should be able to use
this function instead.
---
 headers/posix/locale.h                        |  3 ++-
 src/system/libroot/posix/locale/locale_t.cpp  | 11 +++++++++++
 src/system/libroot/posix/locale/setlocale.cpp |  9 ++-------
 3 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/headers/posix/locale.h b/headers/posix/locale.h
index 46d6103084..797e99f648 100644
--- a/headers/posix/locale.h
+++ b/headers/posix/locale.h
@@ -66,13 +66,14 @@ struct lconv {
 extern "C" {
 #endif
 
-extern struct lconv *localeconv(void);
 extern char *setlocale(int category, const char *locale);
+extern struct lconv *localeconv(void);
 
 extern locale_t duplocale(locale_t);
 extern void freelocale(locale_t);
 extern locale_t newlocale(int, const char *, locale_t);
 extern locale_t uselocale(locale_t);
+const char *getlocalename_l(int category, locale_t locobj);
 
 #ifdef __cplusplus
 }
diff --git a/src/system/libroot/posix/locale/locale_t.cpp b/src/system/libroot/posix/locale/locale_t.cpp
index 780c4cb8c6..416776f7e7 100644
--- a/src/system/libroot/posix/locale/locale_t.cpp
+++ b/src/system/libroot/posix/locale/locale_t.cpp
@@ -260,6 +260,17 @@ uselocale(locale_t newLoc)
 }
 
 
+extern "C" const char*
+getlocalename_l(int category, locale_t l)
+{
+	LocaleBackend* backend = (l == LC_GLOBAL_LOCALE) ?
+		gGlobalLocaleBackend : (LocaleBackend*)((LocaleBackendData*)l)->backend;
+	if (backend == NULL)
+		return "POSIX";
+	return backend->SetLocale(category, NULL);
+}
+
+
 extern "C" locale_t
 __current_locale_t()
 {
diff --git a/src/system/libroot/posix/locale/setlocale.cpp b/src/system/libroot/posix/locale/setlocale.cpp
index 4c1ffccc5b..c77220cb96 100644
--- a/src/system/libroot/posix/locale/setlocale.cpp
+++ b/src/system/libroot/posix/locale/setlocale.cpp
@@ -28,13 +28,8 @@ setlocale(int category, const char* locale)
 	if (category < 0 || category > LC_LAST)
 		return NULL;
 
-	if (locale == NULL) {
-		// query the locale of the given category
-		if (gGlobalLocaleBackend != NULL)
-			return const_cast<char*>(gGlobalLocaleBackend->SetLocale(category, NULL));
-		else
-			return const_cast<char*>("POSIX");
-	}
+	if (locale == NULL)
+		return const_cast<char*>(getlocalename_l(category, LC_GLOBAL_LOCALE));
 
 	// we may have to invoke SetLocale once for each category, so we use an
 	// array to collect the locale per category