Move client-side language code fetching into a single function

src/gettext.cpp

@@ -6,6 +6,7 @@
 #include <cstring>
 #include <iostream>
 #include "gettext.h"
+#include "util/langcode.h"
 #include "util/string.h"
 #include "porting.h"
 #include "log.h"
@@ -146,6 +147,10 @@ static void MSVC_LocaleWorkaround(int argc, char* argv[])
 
 #endif
 
+static std::string configured_locale;
+static std::vector<std::wstring> effective_locale;
+static std::string effective_locale_string;
+
 /******************************************************************************/
 void init_gettext(const char *path, const std::string &configured_language,
 	int argc, char *argv[])
@@ -223,6 +228,17 @@ void init_gettext(const char *path, const std::string &configured_language,
 	setlocale(LC_ALL, "");
 #endif // if USE_GETTEXT
 
+	// Set up locale for in-game translations
+	configured_locale = configured_language;
+	if (configured_locale.empty()) {
+		if (auto lang = getenv("LANGUAGE"); lang && *lang)
+			configured_locale = lang;
+		else
+			configured_locale = getenv("LANG");
+	}
+	effective_locale = parse_language_list(utf8_to_wide(configured_locale));
+	effective_locale_string = wide_to_utf8(str_join(effective_locale, L":"));
+
 	/* no matter what locale is used we need number format to be "C" */
 	/* to ensure formspec parameters are evaluated correctly!        */
 
@@ -230,3 +246,13 @@ void init_gettext(const char *path, const std::string &configured_language,
 	infostream << "Message locale is now set to: "
 			<< setlocale(LC_ALL, 0) << std::endl;
 }
+
+const std::vector<std::wstring> &get_effective_locale()
+{
+	return effective_locale;
+}
+
+const std::string &get_client_language_code()
+{
+	return effective_locale_string;
+}

src/gettext.h

@@ -4,6 +4,7 @@
 
 #pragma once
 
+#include <vector>
 #include "config.h" // for USE_GETTEXT
 #include "porting.h"
 #include "util/string.h"
@@ -103,3 +104,15 @@ inline std::string fmtgettext(const char *format, Args&&... args)
 
 	return buf;
 }
+
+/**
+ * Returns the effective locale setting for in-game translations.
+ * @return A vector of language codes based on priority.
+ */
+const std::vector<std::wstring> &get_effective_locale();
+
+/**
+ * Returns the effective locale setting for in-game translations.
+ * @return A string of the expanded language code.
+ */
+const std::string &get_client_language_code();

src/network/clientpackethandler.cpp

@@ -141,13 +141,7 @@ void Client::handleCommand_AuthAccept(NetworkPacket* pkt)
 					<< m_recommended_send_interval<<std::endl;
 
 	// Reply to server
-	/*~ DO NOT TRANSLATE THIS LITERALLY!
-	This is a special string which needs to contain the translation's
-	language code (e.g. "de" for German). */
-	std::string lang = gettext("LANG_CODE");
-	if (lang == "LANG_CODE")
-		lang.clear();
-
+	std::string lang = get_client_language_code();
 	NetworkPacket resp_pkt(TOSERVER_INIT2, sizeof(u16) + lang.size());
 	resp_pkt << lang;
 	Send(&resp_pkt);

src/script/lua_api/l_client.cpp

@@ -177,10 +177,7 @@ int ModApiClient::l_get_language(lua_State *L)
 #else
 	char *locale = setlocale(LC_MESSAGES, NULL);
 #endif
-	std::string lang = gettext("LANG_CODE");
-	if (lang == "LANG_CODE")
-		lang.clear();
-
+	std::string lang = get_client_language_code();
 	lua_pushstring(L, locale);
 	lua_pushstring(L, lang.c_str());
 	return 2;

src/script/lua_api/l_mainmenu.cpp

@@ -527,9 +527,7 @@ int ModApiMainMenu::l_get_content_translation(lua_State *L)
 	std::string path = luaL_checkstring(L, 1);
 	std::string domain = luaL_checkstring(L, 2);
 	std::string string = luaL_checkstring(L, 3);
-	std::string lang = gettext("LANG_CODE");
-	if (lang == "LANG_CODE")
-		lang = "";
+	std::string lang = get_client_language_code();
 
 	auto *translations = engine->getContentTranslations(path, domain, lang);
 	string = wide_to_utf8(translate_string(utf8_to_wide(string), translations));
@@ -879,10 +877,7 @@ int ModApiMainMenu::l_download_file(lua_State *L)
 /******************************************************************************/
 int ModApiMainMenu::l_get_language(lua_State *L)
 {
-	std::string lang = gettext("LANG_CODE");
-	if (lang == "LANG_CODE")
-		lang = "";
-
+	std::string lang = get_client_language_code();
 	lua_pushstring(L, lang.c_str());
 	return 1;
 }