diff --git a/lua/include/bit.h b/lua/include/bit.h new file mode 100644 index 000000000..b75fdf05c --- /dev/null +++ b/lua/include/bit.h @@ -0,0 +1,17 @@ +#ifndef BIT_H +#define BIT_H + +#define LUA_BITOP_VERSION "1.0.1" + +#define LUA_LIB +#include "lua.h" +#include "lauxlib.h" +#ifdef __cplusplus + extern "C" { +#endif +LUALIB_API int luaopen_bit(lua_State *L); +#ifdef __cplusplus + } +#endif +#endif // BIT_H + diff --git a/lua/src/bit.c b/lua/src/bit.c new file mode 100644 index 000000000..9f2d6f5a2 --- /dev/null +++ b/lua/src/bit.c @@ -0,0 +1,181 @@ +/* +** Lua BitOp -- a bit operations library for Lua 5.1. +** http://bitop.luajit.org/ +** +** Copyright (C) 2008-2009 Mike Pall. All rights reserved. +** +** 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 +** MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. +** IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY +** CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, +** TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE +** SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. +** +** [ MIT license: http://www.opensource.org/licenses/mit-license.php ] +*/ + +#include "bit.h" +#ifdef __cplusplus + extern "C" { +#endif + +#ifdef _MSC_VER +/* MSVC is stuck in the last century and doesn't have C99's stdint.h. */ +typedef __int32 int32_t; +typedef unsigned __int32 uint32_t; +typedef unsigned __int64 uint64_t; +#else +#include +#endif + +typedef int32_t SBits; +typedef uint32_t UBits; + +typedef union { + lua_Number n; +#ifdef LUA_NUMBER_DOUBLE + uint64_t b; +#else + UBits b; +#endif +} BitNum; + +/* Convert argument to bit type. */ +static UBits barg(lua_State *L, int idx) +{ + BitNum bn; + UBits b; + bn.n = lua_tonumber(L, idx); +#if defined(LUA_NUMBER_DOUBLE) + bn.n += 6755399441055744.0; /* 2^52+2^51 */ +#ifdef SWAPPED_DOUBLE + b = (UBits)(bn.b >> 32); +#else + b = (UBits)bn.b; +#endif +#elif defined(LUA_NUMBER_INT) || defined(LUA_NUMBER_LONG) || \ + defined(LUA_NUMBER_LONGLONG) || defined(LUA_NUMBER_LONG_LONG) || \ + defined(LUA_NUMBER_LLONG) + if (sizeof(UBits) == sizeof(lua_Number)) + b = bn.b; + else + b = (UBits)(SBits)bn.n; +#elif defined(LUA_NUMBER_FLOAT) +#error "A 'float' lua_Number type is incompatible with this library" +#else +#error "Unknown number type, check LUA_NUMBER_* in luaconf.h" +#endif + if (b == 0 && !lua_isnumber(L, idx)) + luaL_typerror(L, idx, "number"); + return b; +} + +/* Return bit type. */ +#define BRET(b) lua_pushnumber(L, (lua_Number)(SBits)(b)); return 1; + +static int bit_tobit(lua_State *L) { BRET(barg(L, 1)) } +static int bit_bnot(lua_State *L) { BRET(~barg(L, 1)) } + +#define BIT_OP(func, opr) \ + static int func(lua_State *L) { int i; UBits b = barg(L, 1); \ + for (i = lua_gettop(L); i > 1; i--) b opr barg(L, i); BRET(b) } +BIT_OP(bit_band, &=) +BIT_OP(bit_bor, |=) +BIT_OP(bit_bxor, ^=) + +#define bshl(b, n) (b << n) +#define bshr(b, n) (b >> n) +#define bsar(b, n) ((SBits)b >> n) +#define brol(b, n) ((b << n) | (b >> (32-n))) +#define bror(b, n) ((b << (32-n)) | (b >> n)) +#define BIT_SH(func, fn) \ + static int func(lua_State *L) { \ + UBits b = barg(L, 1); UBits n = barg(L, 2) & 31; BRET(fn(b, n)) } +BIT_SH(bit_lshift, bshl) +BIT_SH(bit_rshift, bshr) +BIT_SH(bit_arshift, bsar) +BIT_SH(bit_rol, brol) +BIT_SH(bit_ror, bror) + +static int bit_bswap(lua_State *L) +{ + UBits b = barg(L, 1); + b = (b >> 24) | ((b >> 8) & 0xff00) | ((b & 0xff00) << 8) | (b << 24); + BRET(b) +} + +static int bit_tohex(lua_State *L) +{ + UBits b = barg(L, 1); + SBits n = lua_isnone(L, 2) ? 8 : (SBits)barg(L, 2); + const char *hexdigits = "0123456789abcdef"; + char buf[8]; + int i; + if (n < 0) { n = -n; hexdigits = "0123456789ABCDEF"; } + if (n > 8) n = 8; + for (i = (int)n; --i >= 0; ) { buf[i] = hexdigits[b & 15]; b >>= 4; } + lua_pushlstring(L, buf, (size_t)n); + return 1; +} + +static const struct luaL_Reg bit_funcs[] = { + { "tobit", bit_tobit }, + { "bnot", bit_bnot }, + { "band", bit_band }, + { "bor", bit_bor }, + { "bxor", bit_bxor }, + { "lshift", bit_lshift }, + { "rshift", bit_rshift }, + { "arshift", bit_arshift }, + { "rol", bit_rol }, + { "ror", bit_ror }, + { "bswap", bit_bswap }, + { "tohex", bit_tohex }, + { NULL, NULL } +}; + +/* Signed right-shifts are implementation-defined per C89/C99. +** But the de facto standard are arithmetic right-shifts on two's +** complement CPUs. This behaviour is required here, so test for it. +*/ +#define BAD_SAR (bsar(-8, 2) != (SBits)-2) + +LUALIB_API int luaopen_bit(lua_State *L) +{ + UBits b; + lua_pushnumber(L, (lua_Number)1437217655L); + b = barg(L, -1); + if (b != (UBits)1437217655L || BAD_SAR) { /* Perform a simple self-test. */ + const char *msg = "compiled with incompatible luaconf.h"; +#ifdef LUA_NUMBER_DOUBLE +#ifdef _WIN32 + if (b == (UBits)1610612736L) + msg = "use D3DCREATE_FPU_PRESERVE with DirectX"; +#endif + if (b == (UBits)1127743488L) + msg = "not compiled with SWAPPED_DOUBLE"; +#endif + if (BAD_SAR) + msg = "arithmetic right-shift broken"; + luaL_error(L, "bit library self-test failed (%s)", msg); + } + luaL_register(L, "bit", bit_funcs); + return 1; +} +#ifdef __cplusplus + } +#endif + +