#include <errno.h>

#include <string.h>

#include "lua.h"

#include "lauxlib.h"

#include "compat-5.2.h"

#if !defined(LUA_VERSION_NUM) || LUA_VERSION_NUM == 501

int lua_absindex (lua_State *L, int i) {

  if (i < 0 && i > LUA_REGISTRYINDEX)

    i += lua_gettop(L) + 1;

  return i;

}

void lua_copy (lua_State *L, int from, int to) {

  int abs_to = lua_absindex(L, to);

  luaL_checkstack(L, 1, "not enough stack slots");

  lua_pushvalue(L, from);

  lua_replace(L, abs_to);

}

void lua_rawgetp (lua_State *L, int i, const void *p) {

  int abs_i = lua_absindex(L, i);

  lua_pushlightuserdata(L, (void*)p);

  lua_rawget(L, abs_i);

}

void lua_rawsetp (lua_State *L, int i, const void *p) {

  int abs_i = lua_absindex(L, i);

  luaL_checkstack(L, 1, "not enough stack slots");

  lua_pushlightuserdata(L, (void*)p);

  lua_insert(L, -2);

  lua_rawset(L, abs_i);

}

void *luaL_testudata (lua_State *L, int i, const char *tname) {

  void *p = lua_touserdata(L, i);

  luaL_checkstack(L, 2, "not enough stack slots");

  if (p == NULL || !lua_getmetatable(L, i))

    return NULL;

  else {

    int res = 0;

    luaL_getmetatable(L, tname);

    res = lua_rawequal(L, -1, -2);

    lua_pop(L, 2);

    if (!res)

      p = NULL;

  }

  return p;

}

lua_Number lua_tonumberx (lua_State *L, int i, int *isnum) {

  lua_Number n = lua_tonumber(L, i);

  if (isnum != NULL) {

    *isnum = (n != 0 || lua_isnumber(L, i));

  }

  return n;

}

#define PACKAGE_KEY "_COMPAT52_PACKAGE"

static void push_package_table (lua_State *L) {

  lua_pushliteral(L, PACKAGE_KEY);

  lua_rawget(L, LUA_REGISTRYINDEX);

  if (!lua_istable(L, -1)) {

    lua_pop(L, 1);

    /* try to get package table from globals */

    lua_pushliteral(L, "package");

    lua_rawget(L, LUA_GLOBALSINDEX);

    if (lua_istable(L, -1)) {

      lua_pushliteral(L, PACKAGE_KEY);

      lua_pushvalue(L, -2);

      lua_rawset(L, LUA_REGISTRYINDEX);

    }

  }

}

void lua_getuservalue (lua_State *L, int i) {

  luaL_checktype(L, i, LUA_TUSERDATA);

  luaL_checkstack(L, 2, "not enough stack slots");

  lua_getfenv(L, i);

  lua_pushvalue(L, LUA_GLOBALSINDEX);

  if (lua_rawequal(L, -1, -2)) {

    lua_pop(L, 1);

    lua_pushnil(L);

    lua_replace(L, -2);

  } else {

    lua_pop(L, 1);

    push_package_table(L);

    if (lua_rawequal(L, -1, -2)) {

      lua_pop(L, 1);

      lua_pushnil(L);

      lua_replace(L, -2);

    } else

      lua_pop(L, 1);

  }

}

void lua_setuservalue (lua_State *L, int i) {

  luaL_checktype(L, i, LUA_TUSERDATA);

  if (lua_isnil(L, -1)) {

    luaL_checkstack(L, 1, "not enough stack slots");

    lua_pushvalue(L, LUA_GLOBALSINDEX);

    lua_replace(L, -2);

  }

  lua_setfenv(L, i);

}

/*

** Adapted from Lua 5.2.0

*/

void luaL_setfuncs (lua_State *L, const luaL_Reg *l, int nup) {

  luaL_checkstack(L, nup+1, "too many upvalues");

  for (; l->name != NULL; l++) {  /* fill the table with given functions */

    int i;

    lua_pushstring(L, l->name);

    for (i = 0; i < nup; i++)  /* copy upvalues to the top */

      lua_pushvalue(L, -(nup + 1));

    lua_pushcclosure(L, l->func, nup);  /* closure with those upvalues */

    lua_settable(L, -(nup + 3)); /* table must be below the upvalues, the name and the closure */

  }

  lua_pop(L, nup);  /* remove upvalues */

}

void luaL_setmetatable (lua_State *L, const char *tname) {

  luaL_checkstack(L, 1, "not enough stack slots");

  luaL_getmetatable(L, tname);

  lua_setmetatable(L, -2);

}

int luaL_getsubtable (lua_State *L, int i, const char *name) {

  int abs_i = lua_absindex(L, i);

  luaL_checkstack(L, 3, "not enough stack slots");

  lua_pushstring(L, name);

  lua_gettable(L, abs_i);

  if (lua_istable(L, -1))

    return 1;

  lua_pop(L, 1);

  lua_newtable(L);

  lua_pushstring(L, name);

  lua_pushvalue(L, -2);

  lua_settable(L, abs_i);

  return 0;

}

#if !defined(COMPAT52_IS_LUAJIT)

static int countlevels (lua_State *L) {

  lua_Debug ar;

  int li = 1, le = 1;

  /* find an upper bound */

  while (lua_getstack(L, le, &ar)) { li = le; le *= 2; }

  /* do a binary search */

  while (li < le) {

    int m = (li + le)/2;

    if (lua_getstack(L, m, &ar)) li = m + 1;

    else le = m;

  }

  return le - 1;

}

static int findfield (lua_State *L, int objidx, int level) {

  if (level == 0 || !lua_istable(L, -1))

    return 0;  /* not found */

  lua_pushnil(L);  /* start 'next' loop */

  while (lua_next(L, -2)) {  /* for each pair in table */

    if (lua_type(L, -2) == LUA_TSTRING) {  /* ignore non-string keys */

      if (lua_rawequal(L, objidx, -1)) {  /* found object? */

        lua_pop(L, 1);  /* remove value (but keep name) */

        return 1;

      }

      else if (findfield(L, objidx, level - 1)) {  /* try recursively */

        lua_remove(L, -2);  /* remove table (but keep name) */

        lua_pushliteral(L, ".");

        lua_insert(L, -2);  /* place '.' between the two names */

        lua_concat(L, 3);

        return 1;

      }

    }

    lua_pop(L, 1);  /* remove value */

  }

  return 0;  /* not found */

}

static int pushglobalfuncname (lua_State *L, lua_Debug *ar) {

  int top = lua_gettop(L);

  lua_getinfo(L, "f", ar);  /* push function */

  lua_pushvalue(L, LUA_GLOBALSINDEX);

  if (findfield(L, top + 1, 2)) {

    lua_copy(L, -1, top + 1);  /* move name to proper place */

    lua_pop(L, 2);  /* remove pushed values */

    return 1;

  }

  else {

    lua_settop(L, top);  /* remove function and global table */

    return 0;

  }

}

static void pushfuncname (lua_State *L, lua_Debug *ar) {

  if (*ar->namewhat != '\0')  /* is there a name? */

    lua_pushfstring(L, "function " LUA_QS, ar->name);

  else if (*ar->what == 'm')  /* main? */

      lua_pushliteral(L, "main chunk");

  else if (*ar->what == 'C') {

    if (pushglobalfuncname(L, ar)) {

      lua_pushfstring(L, "function " LUA_QS, lua_tostring(L, -1));

      lua_remove(L, -2);  /* remove name */

    }

    else

      lua_pushliteral(L, "?");

  }

  else

    lua_pushfstring(L, "function <%s:%d>", ar->short_src, ar->linedefined);

}

#define LEVELS1 12  /* size of the first part of the stack */

#define LEVELS2 10  /* size of the second part of the stack */

void luaL_traceback (lua_State *L, lua_State *L1,

                                const char *msg, int level) {

  lua_Debug ar;

  int top = lua_gettop(L);

  int numlevels = countlevels(L1);

  int mark = (numlevels > LEVELS1 + LEVELS2) ? LEVELS1 : 0;

  if (msg) lua_pushfstring(L, "%s\n", msg);

  lua_pushliteral(L, "stack traceback:");

  while (lua_getstack(L1, level++, &ar)) {

    if (level == mark) {  /* too many levels? */

      lua_pushliteral(L, "\n\t...");  /* add a '...' */

      level = numlevels - LEVELS2;  /* and skip to last ones */

    }

    else {

      lua_getinfo(L1, "Slnt", &ar);

      lua_pushfstring(L, "\n\t%s:", ar.short_src);

      if (ar.currentline > 0)

        lua_pushfstring(L, "%d:", ar.currentline);

      lua_pushliteral(L, " in ");

      pushfuncname(L, &ar);

      lua_concat(L, lua_gettop(L) - top);

    }

  }

  lua_concat(L, lua_gettop(L) - top);

}

#endif

void luaL_checkversion (lua_State *L) {

  (void)L;

}

#if !defined(COMPAT52_IS_LUAJIT)

int luaL_fileresult (lua_State *L, int stat, const char *fname) {

  int en = errno;  /* calls to Lua API may change this value */

  if (stat) {

    lua_pushboolean(L, 1);

    return 1;

  }

  else {

    lua_pushnil(L);

    if (fname)

      lua_pushfstring(L, "%s: %s", fname, strerror(en));

    else

      lua_pushstring(L, strerror(en));

    lua_pushnumber(L, (lua_Number)en);

    return 3;

  }

}

#endif

#endif /* Lua 5.0 or Lua 5.1 */

#if defined(LUA_VERSION_NUM) && LUA_VERSION_NUM == 501

#include <limits.h>

typedef LUAI_INT32 LUA_INT32;

/********************************************************************/

/*                    extract of 5.2's luaconf.h                    */

/*  detects proper defines for faster unsigned<->number conversion  */

/*           see copyright notice at the end of this file           */

/********************************************************************/

#if !defined(LUA_ANSI) && defined(_WIN32) && !defined(_WIN32_WCE)

#define LUA_WIN		/* enable goodies for regular Windows platforms */

#endif

#if defined(LUA_NUMBER_DOUBLE) && !defined(LUA_ANSI)	/* { */

/* Microsoft compiler on a Pentium (32 bit) ? */

#if defined(LUA_WIN) && defined(_MSC_VER) && defined(_M_IX86)	/* { */

#define LUA_MSASMTRICK

#define LUA_IEEEENDIAN		0

#define LUA_NANTRICK

/* pentium 32 bits? */

#elif defined(__i386__) || defined(__i386) || defined(__X86__) /* }{ */

#define LUA_IEEE754TRICK

#define LUA_IEEELL

#define LUA_IEEEENDIAN		0

#define LUA_NANTRICK

/* pentium 64 bits? */

#elif defined(__x86_64)						/* }{ */

#define LUA_IEEE754TRICK

#define LUA_IEEEENDIAN		0

#elif defined(__POWERPC__) || defined(__ppc__)			/* }{ */

#define LUA_IEEE754TRICK

#define LUA_IEEEENDIAN		1

#else								/* }{ */

/* assume IEEE754 and a 32-bit integer type */

#define LUA_IEEE754TRICK

#endif								/* } */

#endif							/* } */

/********************************************************************/

/*                    extract of 5.2's llimits.h                    */

/*       gives us lua_number2unsigned and lua_unsigned2number       */

/*           see copyright notice at the end of this file           */

/********************************************************************/

#if defined(MS_ASMTRICK) || defined(LUA_MSASMTRICK)	/* { */

/* trick with Microsoft assembler for X86 */

#define lua_number2unsigned(i,n)  \

  {__int64 l; __asm {__asm fld n   __asm fistp l} i = (unsigned int)l;}

#elif defined(LUA_IEEE754TRICK)		/* }{ */

/* the next trick should work on any machine using IEEE754 with

   a 32-bit int type */

union compat52_luai_Cast { double l_d; LUA_INT32 l_p[2]; };

#if !defined(LUA_IEEEENDIAN)	/* { */

#define LUAI_EXTRAIEEE	\

  static const union compat52_luai_Cast ieeeendian = {-(33.0 + 6755399441055744.0)};

#define LUA_IEEEENDIANLOC	(ieeeendian.l_p[1] == 33)

#else

#define LUA_IEEEENDIANLOC	LUA_IEEEENDIAN

#define LUAI_EXTRAIEEE		/* empty */

#endif				/* } */

#define lua_number2int32(i,n,t) \

  { LUAI_EXTRAIEEE \

    volatile union compat52_luai_Cast u; u.l_d = (n) + 6755399441055744.0; \

    (i) = (t)u.l_p[LUA_IEEEENDIANLOC]; }

#define lua_number2unsigned(i,n)	lua_number2int32(i, n, lua_Unsigned)

#endif				/* } */

/* the following definitions always work, but may be slow */

#if !defined(lua_number2unsigned)	/* { */

/* the following definition assures proper modulo behavior */

#if defined(LUA_NUMBER_DOUBLE) || defined(LUA_NUMBER_FLOAT)

#include <math.h>

#define SUPUNSIGNED	((lua_Number)(~(lua_Unsigned)0) + 1)

#define lua_number2unsigned(i,n)  \

	((i)=(lua_Unsigned)((n) - floor((n)/SUPUNSIGNED)*SUPUNSIGNED))

#else

#define lua_number2unsigned(i,n)	((i)=(lua_Unsigned)(n))

#endif

#endif				/* } */

#if !defined(lua_unsigned2number)

/* on several machines, coercion from unsigned to double is slow,

   so it may be worth to avoid */

#define lua_unsigned2number(u)  \

    (((u) <= (lua_Unsigned)INT_MAX) ? (lua_Number)(int)(u) : (lua_Number)(u))

#endif

/********************************************************************/

static void compat52_call_lua (lua_State *L, char const code[], size_t len,

                               int nargs, int nret) {

  lua_rawgetp(L, LUA_REGISTRYINDEX, (void*)code);

  if (lua_type(L, -1) != LUA_TFUNCTION) {

    lua_pop(L, 1);

    if (luaL_loadbuffer(L, code, len, "=none"))

      lua_error(L);

    lua_pushvalue(L, -1);

    lua_rawsetp(L, LUA_REGISTRYINDEX, (void*)code);

  }

  lua_insert(L, -nargs-1);

  lua_call(L, nargs, nret);

}

static const char compat52_arith_code[] = {

  'l', 'o', 'c', 'a', 'l', ' ', 'o', 'p', ',', 'a', ',', 'b',

  '=', '.', '.', '.', '\n',

  'i', 'f', ' ', 'o', 'p', '=', '=', '0', ' ',

  't', 'h', 'e', 'n', '\n',

  'r', 'e', 't', 'u', 'r', 'n', ' ', 'a', '+', 'b', '\n',

  'e', 'l', 's', 'e', 'i', 'f', ' ', 'o', 'p', '=', '=', '1', ' ',

  't', 'h', 'e', 'n', '\n',

  'r', 'e', 't', 'u', 'r', 'n', ' ', 'a', '-', 'b', '\n',

  'e', 'l', 's', 'e', 'i', 'f', ' ', 'o', 'p', '=', '=', '2', ' ',

  't', 'h', 'e', 'n', '\n',

  'r', 'e', 't', 'u', 'r', 'n', ' ', 'a', '*', 'b', '\n',

  'e', 'l', 's', 'e', 'i', 'f', ' ', 'o', 'p', '=', '=', '3', ' ',

  't', 'h', 'e', 'n', '\n',

  'r', 'e', 't', 'u', 'r', 'n', ' ', 'a', '/', 'b', '\n',

  'e', 'l', 's', 'e', 'i', 'f', ' ', 'o', 'p', '=', '=', '4', ' ',

  't', 'h', 'e', 'n', '\n',

  'r', 'e', 't', 'u', 'r', 'n', ' ', 'a', '%', 'b', '\n',

  'e', 'l', 's', 'e', 'i', 'f', ' ', 'o', 'p', '=', '=', '5', ' ',

  't', 'h', 'e', 'n', '\n',

  'r', 'e', 't', 'u', 'r', 'n', ' ', 'a', '^', 'b', '\n',

  'e', 'l', 's', 'e', 'i', 'f', ' ', 'o', 'p', '=', '=', '6', ' ',

  't', 'h', 'e', 'n', '\n',

  'r', 'e', 't', 'u', 'r', 'n', ' ', '-', 'a', '\n',

  'e', 'n', 'd', '\n', '\0'

};

void lua_arith (lua_State *L, int op) {

  if (op < LUA_OPADD && op > LUA_OPUNM)

    luaL_error(L, "invalid 'op' argument for lua_arith");

  luaL_checkstack(L, 5, "not enough stack slots");

  if (op == LUA_OPUNM)

    lua_pushvalue(L, -1);

  lua_pushnumber(L, op);

  lua_insert(L, -3);

  compat52_call_lua(L, compat52_arith_code,

                    sizeof(compat52_arith_code)-1, 3, 1);

}

static const char compat52_compare_code[] = {

  'l', 'o', 'c', 'a', 'l', ' ', 'a', ',', 'b', '=', '.', '.', '.', '\n',

  'r', 'e', 't', 'u', 'r', 'n', ' ', 'a', '<', '=', 'b', '\n', '\0'

};

int lua_compare (lua_State *L, int idx1, int idx2, int op) {

  int result = 0;

  switch (op) {

    case LUA_OPEQ:

      return lua_equal(L, idx1, idx2);

    case LUA_OPLT:

      return lua_lessthan(L, idx1, idx2);

    case LUA_OPLE:

      luaL_checkstack(L, 5, "not enough stack slots");

      idx1 = lua_absindex(L, idx1);

      idx2 = lua_absindex(L, idx2);

      lua_pushvalue(L, idx1);

      lua_pushvalue(L, idx2);

      compat52_call_lua(L, (void*)compat52_compare_code,

                        sizeof(compat52_compare_code)-1, 2, 1);

      result = lua_toboolean(L, -1);

      lua_pop(L, 1);

      return result;

    default:

      luaL_error(L, "invalid 'op' argument for lua_compare");

  }

  return 0;

}

void lua_pushunsigned (lua_State *L, lua_Unsigned n) {

  lua_pushnumber(L, lua_unsigned2number(n));

}

lua_Unsigned luaL_checkunsigned (lua_State *L, int i) {

  lua_Unsigned result;

  lua_Number n = lua_tonumber(L, i);

  if (n == 0 && !lua_isnumber(L, i))

    luaL_checktype(L, i, LUA_TNUMBER);

  lua_number2unsigned(result, n);

  return result;

}

lua_Unsigned lua_tounsignedx (lua_State *L, int i, int *isnum) {

  lua_Unsigned result;

  lua_Number n = lua_tonumberx(L, i, isnum);

  lua_number2unsigned(result, n);

  return result;

}

lua_Unsigned luaL_optunsigned (lua_State *L, int i, lua_Unsigned def) {

  return luaL_opt(L, luaL_checkunsigned, i, def);

}

lua_Integer lua_tointegerx (lua_State *L, int i, int *isnum) {

  lua_Integer n = lua_tointeger(L, i);

  if (isnum != NULL) {

    *isnum = (n != 0 || lua_isnumber(L, i));

  }

  return n;

}

void lua_len (lua_State *L, int i) {

  switch (lua_type(L, i)) {

    case LUA_TSTRING: /* fall through */

    case LUA_TTABLE:

      if (!luaL_callmeta(L, i, "__len"))

        lua_pushnumber(L, (int)lua_objlen(L, i));

      break;

    case LUA_TUSERDATA:

      if (luaL_callmeta(L, i, "__len"))

        break;

      /* maybe fall through */

    default:

      luaL_error(L, "attempt to get length of a %s value",

                 lua_typename(L, lua_type(L, i)));

  }

}

int luaL_len (lua_State *L, int i) {

  int res = 0, isnum = 0;

  luaL_checkstack(L, 1, "not enough stack slots");

  lua_len(L, i);

  res = (int)lua_tointegerx(L, -1, &isnum);

  lua_pop(L, 1);

  if (!isnum)

    luaL_error(L, "object length is not a number");

  return res;

}

const char *luaL_tolstring (lua_State *L, int idx, size_t *len) {

  if (!luaL_callmeta(L, idx, "__tostring")) {

    int t = lua_type(L, idx);

    switch (t) {

      case LUA_TNIL:

        lua_pushliteral(L, "nil");

        break;

      case LUA_TSTRING:

      case LUA_TNUMBER:

        lua_pushvalue(L, idx);

        break;

      case LUA_TBOOLEAN:

        if (lua_toboolean(L, idx))

          lua_pushliteral(L, "true");

        else

          lua_pushliteral(L, "false");

        break;

      default:

        lua_pushfstring(L, "%s: %p", lua_typename(L, t),

                                     lua_topointer(L, idx));

        break;

    }

  }

  return lua_tolstring(L, -1, len);

}

void luaL_requiref (lua_State *L, char const* modname,

                    lua_CFunction openf, int glb) {

  luaL_checkstack(L, 3, "not enough stack slots");

  lua_pushcfunction(L, openf);

  lua_pushstring(L, modname);

  lua_call(L, 1, 1);

  lua_getglobal(L, "package");

  lua_getfield(L, -1, "loaded");

  lua_replace(L, -2);

  lua_pushvalue(L, -2);

  lua_setfield(L, -2, modname);

  lua_pop(L, 1);

  if (glb) {

    lua_pushvalue(L, -1);

    lua_setglobal(L, modname);

  }

}

void luaL_buffinit (lua_State *L, luaL_Buffer_52 *B) {

  /* make it crash if used via pointer to a 5.1-style luaL_Buffer */

  B->b.p = NULL;

  B->b.L = NULL;

  B->b.lvl = 0;

  /* reuse the buffer from the 5.1-style luaL_Buffer though! */

  B->ptr = B->b.buffer;

  B->capacity = LUAL_BUFFERSIZE;

  B->nelems = 0;

  B->L2 = L;

}

char *luaL_prepbuffsize (luaL_Buffer_52 *B, size_t s) {

  if (B->capacity - B->nelems < s) { /* needs to grow */

    char* newptr = NULL;

    size_t newcap = B->capacity * 2;

    if (newcap - B->nelems < s)

      newcap = B->nelems + s;

    if (newcap < B->capacity) /* overflow */

      luaL_error(B->L2, "buffer too large");

    newptr = lua_newuserdata(B->L2, newcap);

    memcpy(newptr, B->ptr, B->nelems);

    if (B->ptr != B->b.buffer)

      lua_replace(B->L2, -2); /* remove old buffer */

    B->ptr = newptr;

    B->capacity = newcap;

  }

  return B->ptr+B->nelems;

}

void luaL_addlstring (luaL_Buffer_52 *B, const char *s, size_t l) {

  memcpy(luaL_prepbuffsize(B, l), s, l);

  luaL_addsize(B, l);

}

void luaL_addvalue (luaL_Buffer_52 *B) {

  size_t len = 0;

  const char *s = lua_tolstring(B->L2, -1, &len;;

  if (!s)

    luaL_error(B->L2, "cannot convert value to string");

  if (B->ptr != B->b.buffer)

    lua_insert(B->L2, -2); /* userdata buffer must be at stack top */

  luaL_addlstring(B, s, len);

  lua_remove(B->L2, B->ptr != B->b.buffer ? -2 : -1);

}

void luaL_pushresult (luaL_Buffer_52 *B) {

  lua_pushlstring(B->L2, B->ptr, B->nelems);

  if (B->ptr != B->b.buffer)

    lua_replace(B->L2, -2); /* remove userdata buffer */

}

#endif /* LUA_VERSION_NUM == 501 */

/*********************************************************************

* This file contains parts of Lua 5.2's source code:

*

* Copyright (C) 1994-2013 Lua.org, PUC-Rio.

*

* Permission is hereby granted, free of charge, to any person obtaining

* a copy of this software and associated documentation files (the

* "Software"), to deal in the Software without restriction, including

* without limitation the rights to use, copy, modify, merge, publish,

* distribute, sublicense, and/or sell copies of the Software, and to

* permit persons to whom the Software is furnished to do so, subject to

* the following conditions:

*

* The above copyright notice and this permission notice shall be

* included in all copies or substantial portions of the Software.

*

* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,

* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF

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