Add build info and active video_driver, limit debug.txt lines, fix ou…

…tdated minetest.conf being read

builtin/mainmenu/tab_about.lua

@@ -122,27 +122,65 @@ end
 local function read_text_file(path)
 	local f = io.open(path, "r")
 	if not f then
-		return nil
+		return "[not available]\n"
 	end
     local text = f:read("*all")
     f:close()
 	return text
 end
 
+local function tail(str, num_lines)
+	local first_char = 1
+
+	local str_reversed = str:reverse()
+	local index = #str
+	local num_newlines = 0
+	for char in str_reversed:gmatch(".") do
+		if char == "\n" then -- catches CRLF as well
+			num_newlines = num_newlines + 1
+		end
+		if num_newlines > num_lines then
+			first_char = index + 1
+			break
+		end
+		index = index - 1
+	end
+
+	return str:sub(first_char)
+end
+
+-- TODO move these unittests somewhere else
+
+local test_str = "123456\n234567\n345678\n456789\n"
+
+assert(tail(test_str, -math.huge) == "")
+assert(tail(test_str, -1) == "")
+assert(tail(test_str, 0) == "")
+assert(tail(test_str, 1) == "456789\n")
+assert(tail(test_str, 2) == "345678\n456789\n")
+assert(tail(test_str, 3) == "234567\n345678\n456789\n")
+assert(tail(test_str, 4) == test_str)
+assert(tail(test_str, math.huge) == test_str)
+
 local function collect_debug_info()
 	local version = core.get_version()
+	local build_info = core.get_build_info()
 	local irrlicht_device = core.get_active_irrlicht_device()
+	local driver = core.get_active_driver()
 	local renderer = core.get_active_renderer()
 
 	local path_prefix = core.get_user_path() .. DIR_DELIM
-	local minetest_conf = read_text_file(path_prefix .. "minetest.conf") or "[not available]\n"
-	local debug_txt = read_text_file(path_prefix .. "debug.txt") or "[not available]\n"
+	-- Write the current settings to "minetest.conf" so we don't read outdated ones.
+	core.settings:write()
+	local minetest_conf = read_text_file(path_prefix .. "minetest.conf")
+	local debug_txt = tail(read_text_file(path_prefix .. "debug.txt"), 64)
 
 	return table.concat({
-		version.project, " ", (version.hash or version.string), "\n",
-		"Platform: ", PLATFORM, "\n",
-		"Active Irrlicht device: ", irrlicht_device, "\n",
-		"Active renderer: ", renderer, "\n\n",
+		version.project, " ", (version.hash or version.string), " (", PLATFORM, ")\n",
+		build_info, "\n\n",
+		"Active Irrlicht device = ", irrlicht_device, "\n",
+		"Active \"video_driver\"  = ", driver, "\n", -- not redundant!
+		"Active renderer        = ", renderer, "\n\n",
 		"minetest.conf\n",
 		"-------------\n",
 		minetest_conf, "\n",

src/main.cpp

@@ -54,15 +54,6 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 	#include "gui/touchscreengui.h"
 #endif
 
-// for version information only
-extern "C" {
-#if USE_LUAJIT
-	#include <luajit.h>
-#else
-	#include <lua.h>
-#endif
-}
-
 #if !defined(__cpp_rtti) || !defined(__cpp_exceptions)
 #error Minetest cannot be built without exceptions or RTTI
 #endif
@@ -423,14 +414,6 @@ static void print_version()
 {
 	std::cout << PROJECT_NAME_C " " << g_version_hash
 		<< " (" << porting::getPlatformName() << ")" << std::endl;
-#ifndef SERVER
-	std::cout << "Using Irrlicht " IRRLICHT_SDK_VERSION << std::endl;
-#endif
-#if USE_LUAJIT
-	std::cout << "Using " << LUAJIT_VERSION << std::endl;
-#else
-	std::cout << "Using " << LUA_RELEASE << std::endl;
-#endif
 	std::cout << g_build_info << std::endl;
 }
 

src/script/lua_api/l_mainmenu.cpp

@@ -981,6 +981,13 @@ int ModApiMainMenu::l_get_active_irrlicht_device(lua_State *L)
 	return 1;
 }
 
+/******************************************************************************/
+int ModApiMainMenu::l_get_build_info(lua_State *L)
+{
+	lua_pushstring(L, g_build_info);
+	return 1;
+}
+
 /******************************************************************************/
 int ModApiMainMenu::l_get_min_supp_proto(lua_State *L)
 {
@@ -1134,6 +1141,7 @@ void ModApiMainMenu::Initialize(lua_State *L, int top)
 	API_FCT(get_active_driver);
 	API_FCT(get_active_renderer);
 	API_FCT(get_active_irrlicht_device);
+	API_FCT(get_build_info);
 	API_FCT(get_min_supp_proto);
 	API_FCT(get_max_supp_proto);
 	API_FCT(open_url);

src/script/lua_api/l_mainmenu.h

@@ -112,6 +112,8 @@ class ModApiMainMenu: public ModApiBase
 
 	static int l_get_active_irrlicht_device(lua_State *L);
 
+	static int l_get_build_info(lua_State *L);
+
 	// filesystem
 
 	static int l_get_mainmenu_path(lua_State *L);

src/version.cpp

@@ -24,6 +24,16 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 	#include "cmake_config_githash.h"
 #endif
 
+// Included for version information.
+#include "IrrCompileConfig.h"
+extern "C" {
+#if USE_LUAJIT
+	#include <luajit.h>
+#else
+	#include <lua.h>
+#endif
+}
+
 #ifndef VERSION_GITHASH
 	#define VERSION_GITHASH VERSION_STRING
 #endif
@@ -34,6 +44,14 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 const char *g_version_string = VERSION_STRING;
 const char *g_version_hash = VERSION_GITHASH;
 const char *g_build_info =
+#ifndef SERVER
+	"Using Irrlicht " IRRLICHT_SDK_VERSION "\n"
+#endif
+#if USE_LUAJIT
+	"Using " LUAJIT_VERSION "\n"
+#else
+	"Using " LUA_RELEASE "\n"
+#endif
 	"BUILD_TYPE=" BUILD_TYPE "\n"
 	"RUN_IN_PLACE=" STR(RUN_IN_PLACE) "\n"
 	"USE_CURL=" STR(USE_CURL) "\n"