WIP Initial integration of gettextpo/gettext-migration-1

- Convert few messages to new API
- Create template file (dosbox.pot)
- Create tiny translation file for polish (pl/dosbox.po)
- To test: compile dosbox.mo (using e.g. poedit), and place it in
  ./pl/LC_MESSAGES/dosbox.mo
  then run:

      LANGUAGE=pl ./src/dosbox

- TODO: gettext converts to US-ASCII (removes diacritics) (good!),
        but dos can't show them - synchronize gettext conversion
        with used codepage (e.g. 'keyb pl` loads codapage 852, so
        so when recompiled with CP852 instead of US-ASCII, the polish
        letters are perfect) - make it switch in runtime

8 files changed, 106 insertions, 7 deletions

diff --git a/include/dosbox.h b/include/dosbox.h
index b3baa7c47..8f7ed50c2 100644
--- a/include/dosbox.h
+++ b/include/dosbox.h
@@ -23,11 +23,21 @@
 #include "compiler.h"
 #include "types.h"
 
+#include <libintl.h>
+#include <locale.h>
+
 [[noreturn]] void E_Exit(const char *message, ...)
         GCC_ATTRIBUTE(__format__(__printf__, 1, 2));
 
-void MSG_Add(const char*,const char*); //add messages to the internal languagefile
-const char* MSG_Get(char const *);     //get messages from the internal languagefile
+#define _(STRING) gettext(STRING)
+
+// Add message to the internal languagefile
+// DEPRECATED - use gettext instead
+void MSG_Add(const char *, const char *);
+
+// Get messages from the internal languagefile
+// DEPRECATED - use gettext instead
+const char *MSG_Get(char const *);
 
 class Section;
 
diff --git a/po/dosbox.pot b/po/dosbox.pot
new file mode 100644
index 000000000..6b0a149de
--- /dev/null
+++ b/po/dosbox.pot
@@ -0,0 +1,28 @@
+# SOME DESCRIPTIVE TITLE.
+# Copyright (C) YEAR THE PACKAGE'S COPYRIGHT HOLDER
+# This file is distributed under the same license as the dosbox-staging package.
+# FIRST AUTHOR <EMAIL@ADDRESS>, YEAR.
+#
+#, fuzzy
+msgid ""
+msgstr ""
+"Project-Id-Version: dosbox-staging\n"
+"Report-Msgid-Bugs-To: \n"
+"POT-Creation-Date: 2020-12-13 18:19+0100\n"
+"PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
+"Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
+"Language-Team: LANGUAGE <LL@li.org>\n"
+"Language: \n"
+"MIME-Version: 1.0\n"
+"Content-Type: text/plain; charset=CHARSET\n"
+"Content-Transfer-Encoding: 8bit\n"
+
+#: src/shell/shell_cmds.cpp:839
+#, c-format
+msgid "ls: cannot access '%s': No such file or directory\n"
+msgstr ""
+
+#. l10n This message must not end in a newline
+#: src/shell/shell_cmds.cpp:1312
+msgid "Press any key to continue..."
+msgstr ""
diff --git a/po/pl/dosbox.po b/po/pl/dosbox.po
new file mode 100644
index 000000000..f56673455
--- /dev/null
+++ b/po/pl/dosbox.po
@@ -0,0 +1,29 @@
+# SOME DESCRIPTIVE TITLE.
+# Copyright (C) YEAR THE PACKAGE'S COPYRIGHT HOLDER
+# This file is distributed under the same license as the dosbox-staging package.
+# FIRST AUTHOR <EMAIL@ADDRESS>, YEAR.
+#
+msgid ""
+msgstr ""
+"Project-Id-Version: dosbox-staging\n"
+"Report-Msgid-Bugs-To: \n"
+"POT-Creation-Date: 2020-12-13 18:19+0100\n"
+"PO-Revision-Date: 2020-12-13 20:17+0100\n"
+"Language-Team: \n"
+"MIME-Version: 1.0\n"
+"Content-Type: text/plain; charset=UTF-8\n"
+"Content-Transfer-Encoding: 8bit\n"
+"X-Generator: Poedit 2.4.2\n"
+"Last-Translator: Patryk Obara <dreamer.tan@gmail.com>\n"
+"Plural-Forms: nplurals=3; plural=(n==1 ? 0 : n%10>=2 && n%10<=4 && (n%100<12 || n%100>14) ? 1 : 2);\n"
+"Language: pl\n"
+
+#: src/shell/shell_cmds.cpp:839
+#, c-format
+msgid "ls: cannot access '%s': No such file or directory\n"
+msgstr "ls: nie ma dostępu do '%s': Nie ma takiego pliku ani katalogu\n"
+
+#. l10n This message must not end in a newline
+#: src/shell/shell_cmds.cpp:1312
+msgid "Press any key to continue..."
+msgstr "Naciśnij dowolny klawisz, aby kontynuować..."
diff --git a/po/sources.txt b/po/sources.txt
new file mode 100644
index 000000000..4b4e4e39a
--- /dev/null
+++ b/po/sources.txt
@@ -0,0 +1 @@
+src/shell/shell_cmds.cpp
diff --git a/scripts/extract-text.sh b/scripts/extract-text.sh
new file mode 100755
index 000000000..19050fd34
--- /dev/null
+++ b/scripts/extract-text.sh
@@ -0,0 +1,18 @@
+#!/bin/bash
+
+# SPDX-License-Identifier: GPL-2.0-or-later
+
+# Copyright (C) 2020  Patryk Obara <patryk.obara@gmail.com>
+
+# This script exists only to easily generate/update gettext translation
+# template file (dosbox.pot).
+
+cd "$(git rev-parse --show-toplevel)"
+
+xgettext \
+	--verbose \
+	--keyword=_ \
+	--add-comments=l10n \
+	--package-name=dosbox-staging \
+	--files-from=po/sources.txt \
+	-o po/dosbox.pot
diff --git a/src/gui/sdlmain.cpp b/src/gui/sdlmain.cpp
index 528ff5473..e1c6f5c17 100644
--- a/src/gui/sdlmain.cpp
+++ b/src/gui/sdlmain.cpp
@@ -3203,6 +3203,20 @@ void OverrideWMClass()
 #endif
 }
 
+void setup_i18n_env()
+{
+	setlocale(LC_ALL, "");
+	// PWD -> ./pl/LC_MESSAGES/dosbox.mo
+	bindtextdomain("dosbox", getenv("PWD"));
+	textdomain("dosbox");
+
+	//const char *pl_code = "CP852"; // to test: `keyb pl`
+	const char *default_code = "US-ASCII";
+	//const char *code = bind_textdomain_codeset("dosbox", pl_code);
+	const char *code = bind_textdomain_codeset("dosbox", default_code);
+	DEBUG_LOG_MSG("gettext encoding: %s", code);
+}
+
 //extern void UI_Init(void);
 int main(int argc, char* argv[]) {
 	int rcode = 0; // assume good until proven otherwise
@@ -3211,6 +3225,7 @@ int main(int argc, char* argv[]) {
 		OverrideWMClass(); // Before SDL2 video subsystem is initialized
 
 		CROSS_DetermineConfigPaths();
+		setup_i18n_env();
 
 		CommandLine com_line(argc,argv);
 		Config myconf(&com_line);
diff --git a/src/shell/shell.cpp b/src/shell/shell.cpp
index 1da6b3aa3..b922d1904 100644
--- a/src/shell/shell.cpp
+++ b/src/shell/shell.cpp
@@ -612,7 +612,6 @@ void SHELL_Init() {
 	MSG_Add("SHELL_CMD_DIR_BYTES_FREE","%17d dir(s)  %21s bytes free\n");
 	MSG_Add("SHELL_EXECUTE_DRIVE_NOT_FOUND","Drive %c does not exist!\nYou must \033[31mmount\033[0m it first. Type \033[1;33mintro\033[0m or \033[1;33mintro mount\033[0m for more information.\n");
 	MSG_Add("SHELL_EXECUTE_ILLEGAL_COMMAND","Illegal command: %s.\n");
-	MSG_Add("SHELL_CMD_PAUSE","Press any key to continue...");
 	MSG_Add("SHELL_CMD_PAUSE_HELP","Waits for 1 keystroke to continue.\n");
 	MSG_Add("SHELL_CMD_COPY_FAILURE","Copy failure : %s.\n");
 	MSG_Add("SHELL_CMD_COPY_SUCCESS","   %d File(s) copied.\n");
@@ -713,8 +712,6 @@ void SHELL_Init() {
 
 	MSG_Add("SHELL_CMD_LS_HELP", "List directory contents.\n");
 	MSG_Add("SHELL_CMD_LS_HELP_LONG", "ls [/?] [PATTERN]\n");
-	MSG_Add("SHELL_CMD_LS_PATH_ERR",
-	        "ls: cannot access '%s': No such file or directory\n");
 
 	MSG_Add("SHELL_CMD_CHOICE_HELP","Waits for a keypress and sets ERRORLEVEL.\n");
 	MSG_Add("SHELL_CMD_CHOICE_HELP_LONG","CHOICE [/C:choices] [/N] [/S] text\n"
diff --git a/src/shell/shell_cmds.cpp b/src/shell/shell_cmds.cpp
index 3258b0a8c..6a86a0548 100644
--- a/src/shell/shell_cmds.cpp
+++ b/src/shell/shell_cmds.cpp
@@ -836,7 +836,7 @@ void DOS_Shell::CMD_LS(char *args)
 
 	const std::string pattern = to_search_pattern(args);
 	if (!DOS_FindFirst(pattern.c_str(), 0xffff & ~DOS_ATTR_VOLUME)) {
-		WriteOut(MSG_Get("SHELL_CMD_LS_PATH_ERR"), trim(args));
+		WriteOut(_("ls: cannot access '%s': No such file or directory\n"), trim(args));
 		dos.dta(original_dta);
 		return;
 	}
@@ -1308,7 +1308,8 @@ void DOS_Shell::CMD_REM(char * args) {
 
 void DOS_Shell::CMD_PAUSE(char *args) {
 	HELP("PAUSE");
-	WriteOut(MSG_Get("SHELL_CMD_PAUSE"));
+	// l10n This message must not end in a newline
+	WriteOut(_("Press any key to continue..."));
 	uint8_t c;
 	uint16_t n = 1;
 	DOS_ReadFile(STDIN, &c, &n);