add liblua wrapper and build-scripts

libs/lua/luastate.cc

@@ -0,0 +1,106 @@
+/*
+ * Copyright (C) 2016 Robin Gareus <robin@gareus.org>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+#include <assert.h>
+#include "lua/luastate.h"
+
+// from lauxlib.c
+static int panic (lua_State *L) {
+	lua_writestringerror("PANIC: unprotected error in call to Lua API (%s)\n",
+			lua_tostring(L, -1));
+	return 0;  /* return to Lua to abort */
+}
+
+LuaState::LuaState()
+	: L (luaL_newstate ())
+{
+	assert (L);
+	init ();
+}
+
+LuaState::LuaState(lua_State *ls)
+	: L (ls)
+{
+	assert (L);
+	init ();
+}
+
+LuaState::~LuaState() {
+	lua_close (L);
+}
+
+void
+LuaState::init() {
+	lua_atpanic (L, &panic);
+	luaL_openlibs (L);
+	lua_pushlightuserdata (L, this);
+	lua_pushcclosure (L, &LuaState::_print, 1);
+	lua_setglobal (L, "print");
+}
+
+int
+LuaState::do_command (std::string cmd) {
+	int result = luaL_dostring (L, cmd.c_str());
+	if (result != 0) {
+		print ("Error: " + std::string (lua_tostring (L, -1)));
+	}
+	return result;
+}
+
+int
+LuaState::do_file (std::string fn) {
+	int result = luaL_dofile (L, fn.c_str());
+	if (result != 0) {
+		print ("Error: " + std::string (lua_tostring (L, -1)));
+	}
+	return result;
+}
+
+void
+LuaState::collect_garbage () {
+	lua_gc (L, LUA_GCCOLLECT, 0);
+}
+
+void
+LuaState::print (std::string text) {
+	Print (text); /* EMIT SIGNAL */
+}
+
+int
+LuaState::_print (lua_State *L) {
+	LuaState* const luaState = static_cast <LuaState*> (lua_touserdata (L, lua_upvalueindex (1)));
+	std::string text;
+	int n = lua_gettop(L);  /* number of arguments */
+	int i;
+	lua_getglobal(L, "tostring");
+	for (i=1; i<=n; i++) {
+		const char *s;
+		size_t l;
+		lua_pushvalue(L, -1);  /* function to be called */
+		lua_pushvalue(L, i);   /* value to print */
+		lua_call(L, 1, 1);
+		s = lua_tolstring(L, -1, &l);  /* get result */
+		if (s == NULL)
+			return luaL_error(L, "'tostring' must return a string to 'print'");
+		if (i > 1) text += " ";
+		text += std::string (s, l);
+		lua_pop(L, 1);  /* pop result */
+	}
+	luaState->print (text);
+	return 0;
+}