Scripting WIP

src/script.cpp

@@ -0,0 +1,130 @@
+/*
+Minetest-c55
+Copyright (C) 2011 celeron55, Perttu Ahola <celeron55@gmail.com>
+
+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 "script.h"
+#include <cstdarg>
+#include <cstring>
+#include <cstdio>
+#include <cstdlib>
+#include "log.h"
+#include <iostream>
+
+extern "C" {
+#include <lua.h>
+#include <lualib.h>
+#include <lauxlib.h>
+}
+
+void script_error(lua_State *L, const char *fmt, ...)
+{
+	va_list argp;
+	va_start(argp, fmt);
+	vfprintf(stderr, fmt, argp);
+	va_end(argp);
+	lua_close(L);
+	exit(EXIT_FAILURE);
+}
+
+void script_call_va(lua_State *L, const char *func, const char *sig, ...)
+{
+	va_list vl;
+	int narg, nres; /* number of arguments and results */
+
+	va_start(vl, sig);
+	lua_getglobal(L, func); /* push function */
+
+	for (narg = 0; *sig; narg++) {
+		/* repeat for each argument */
+		/* check stack space */
+		luaL_checkstack(L, 1, "too many arguments");
+		switch (*sig++) {
+		case 'd': /* double argument */
+			lua_pushnumber(L, va_arg(vl, double));
+			break;
+		case 'i': /* int argument */
+			lua_pushinteger(L, va_arg(vl, int));
+			break;
+		case 's': /* string argument */
+			lua_pushstring(L, va_arg(vl, char *));
+			break;
+		case '>': /* end of arguments */
+			goto endargs;
+		default:
+			script_error(L, "invalid option (%c)", *(sig - 1));
+		}
+	}
+endargs:
+
+	nres = strlen(sig); /* number of expected results */
+
+	if (lua_pcall(L, narg, nres, 0) != 0) /* do the call */
+		script_error(L, "error calling '%s': %s", func, lua_tostring(L, -1));
+	
+	nres = -nres; /* stack index of first result */
+	while (*sig) { /* repeat for each result */
+		switch (*sig++) {
+		case 'd': /* double result */
+			if (!lua_isnumber(L, nres))
+			script_error(L, "wrong result type");
+			*va_arg(vl, double *) = lua_tonumber(L, nres);
+			break;
+		case 'i': /* int result */
+			if (!lua_isnumber(L, nres))
+			script_error(L, "wrong result type");
+			*va_arg(vl, int *) = lua_tointeger(L, nres);
+			break;
+		case 's': /* string result */
+			if (!lua_isstring(L, nres))
+			script_error(L, "wrong result type");
+			*va_arg(vl, const char **) = lua_tostring(L, nres);
+			break;
+		default:
+			script_error(L, "invalid option (%c)", *(sig - 1));
+		}
+		nres++;
+	}
+
+	va_end(vl);
+}
+
+bool script_load(lua_State *L, const char *path)
+{
+	infostream<<"Loading and running script from "<<path<<std::endl;
+	int ret = luaL_loadfile(L, path) || lua_pcall(L, 0, 0, 0);
+	if(ret){
+		errorstream<<"Failed to load and run script from "<<path<<": "<<lua_tostring(L, -1)<<std::endl;
+		lua_pop(L, 1); // Pop error message from stack
+		return false;
+	}
+	return true;
+}
+
+lua_State* script_init()
+{
+	lua_State *L = luaL_newstate();
+	luaL_openlibs(L);
+	return L;
+}
+
+lua_State* script_deinit(lua_State *L)
+{
+	lua_close(L);
+}
+
+