minetest/src/script/common/c_internal.h

/*
Minetest
Copyright (C) 2013 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 Lesser General Public License as published by
the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.

You should have received a copy of the GNU Lesser 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.
*/

/******************************************************************************/
/******************************************************************************/
/* WARNING!!!! do NOT add this header in any include file or any code file    */
/*             not being a modapi file!!!!!!!!                                */
/******************************************************************************/
/******************************************************************************/

#pragma once

extern "C" {
#include <lua.h>
#include <lauxlib.h>
}

#include "common/c_types.h"


/*
	Define our custom indices into the Lua registry table.

	Lua 5.2 and above define the LUA_RIDX_LAST macro. Only numbers above that
	may be used for custom indices, anything else is reserved.

	Lua 5.1 / LuaJIT do not use any numeric indices (only string indices),
	so we can use numeric indices freely.
*/
#ifdef LUA_RIDX_LAST
#define CUSTOM_RIDX_BASE ((LUA_RIDX_LAST)+1)
#else
#define CUSTOM_RIDX_BASE 1
#endif

#define CUSTOM_RIDX_SCRIPTAPI           (CUSTOM_RIDX_BASE)
#define CUSTOM_RIDX_GLOBALS_BACKUP      (CUSTOM_RIDX_BASE + 1)
#define CUSTOM_RIDX_CURRENT_MOD_NAME    (CUSTOM_RIDX_BASE + 2)
#define CUSTOM_RIDX_BACKTRACE           (CUSTOM_RIDX_BASE + 3)

// Pushes the error handler onto the stack and returns its index
#define PUSH_ERROR_HANDLER(L) \
	(lua_rawgeti((L), LUA_REGISTRYINDEX, CUSTOM_RIDX_BACKTRACE), lua_gettop((L)))

#define PCALL_RESL(L, RES) {                            \
	int result_ = (RES);                                \
	if (result_ != 0) {                                 \
		script_error((L), result_, NULL, __FUNCTION__); \
	}                                                   \
}

#define script_run_callbacks(L, nargs, mode) \
	script_run_callbacks_f((L), (nargs), (mode), __FUNCTION__)

// What script_run_callbacks does with the return values of callbacks.
// Regardless of the mode, if only one callback is defined,
// its return value is the total return value.
// Modes only affect the case where 0 or >= 2 callbacks are defined.
enum RunCallbacksMode
{
	// Returns the return value of the first callback
	// Returns nil if list of callbacks is empty
	RUN_CALLBACKS_MODE_FIRST,
	// Returns the return value of the last callback
	// Returns nil if list of callbacks is empty
	RUN_CALLBACKS_MODE_LAST,
	// If any callback returns a false value, the first such is returned
	// Otherwise, the first callback's return value (trueish) is returned
	// Returns true if list of callbacks is empty
	RUN_CALLBACKS_MODE_AND,
	// Like above, but stops calling callbacks (short circuit)
	// after seeing the first false value
	RUN_CALLBACKS_MODE_AND_SC,
	// If any callback returns a true value, the first such is returned
	// Otherwise, the first callback's return value (falseish) is returned
	// Returns false if list of callbacks is empty
	RUN_CALLBACKS_MODE_OR,
	// Like above, but stops calling callbacks (short circuit)
	// after seeing the first true value
	RUN_CALLBACKS_MODE_OR_SC,
	// Note: "a true value" and "a false value" refer to values that
	// are converted by readParam<bool> to true or false, respectively.
};

std::string script_get_backtrace(lua_State *L);
int script_exception_wrapper(lua_State *L, lua_CFunction f);
void script_error(lua_State *L, int pcall_result, const char *mod, const char *fxn);
void script_run_callbacks_f(lua_State *L, int nargs,
	RunCallbacksMode mode, const char *fxn);
void log_deprecated(lua_State *L, const std::string &message);