From 1d120035557c04002fbb5660e43e6175dbfa3871 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E6=9D=8E=E9=80=9A=E6=B4=B2?= <zhangsongcui3371@sina.com>
Date: Wed, 12 Aug 2026 10:19:22 +0800
Subject: [PATCH] Locale (Windows): uses $LANG if available e.g. MSYS2

---
 src/detection/locale/locale_windows.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/src/detection/locale/locale_windows.c b/src/detection/locale/locale_windows.c
index 0f17e8bfa..4f5896667 100644
--- a/src/detection/locale/locale_windows.c
+++ b/src/detection/locale/locale_windows.c
@@ -1,9 +1,19 @@
 #include "detection/locale/locale.h"
 #include "common/windows/unicode.h"
 
-#include <windows.h>
+#include <winnls.h>
 
 const char* ffDetectLocale(FFstrbuf* result) {
+    ffStrbufAppendS(result, getenv("LC_ALL"));
+    if (result->length > 0) {
+        return nullptr;
+    }
+
+    ffStrbufAppendS(result, getenv("LANG")); // Available in MSYS2 and Cygwin
+    if (result->length > 0) {
+        return nullptr;
+    }
+
     wchar_t name[LOCALE_NAME_MAX_LENGTH];
     int size = GetUserDefaultLocaleName(name, LOCALE_NAME_MAX_LENGTH);
     if (size <= 1) { // including '\0'