diff options
Diffstat (limited to 'src/lib/lualib/lbitlib.c')
-rw-r--r-- | src/lib/lualib/lbitlib.c | 233 |
1 files changed, 0 insertions, 233 deletions
diff --git a/src/lib/lualib/lbitlib.c b/src/lib/lualib/lbitlib.c deleted file mode 100644 index 1cb1d5b..0000000 --- a/src/lib/lualib/lbitlib.c +++ /dev/null @@ -1,233 +0,0 @@ -/* -** $Id: lbitlib.c,v 1.30 2015/11/11 19:08:09 roberto Exp $ -** Standard library for bitwise operations -** See Copyright Notice in lua.h -*/ - -#define lbitlib_c -#define LUA_LIB - -#include "lprefix.h" - - -#include "lua.h" - -#include "lauxlib.h" -#include "lualib.h" - - -#if defined(LUA_COMPAT_BITLIB) /* { */ - - -#define pushunsigned(L,n) lua_pushinteger(L, (lua_Integer)(n)) -#define checkunsigned(L,i) ((lua_Unsigned)luaL_checkinteger(L,i)) - - -/* number of bits to consider in a number */ -#if !defined(LUA_NBITS) -#define LUA_NBITS 32 -#endif - - -/* -** a lua_Unsigned with its first LUA_NBITS bits equal to 1. (Shift must -** be made in two parts to avoid problems when LUA_NBITS is equal to the -** number of bits in a lua_Unsigned.) -*/ -#define ALLONES (~(((~(lua_Unsigned)0) << (LUA_NBITS - 1)) << 1)) - - -/* macro to trim extra bits */ -#define trim(x) ((x) & ALLONES) - - -/* builds a number with 'n' ones (1 <= n <= LUA_NBITS) */ -#define mask(n) (~((ALLONES << 1) << ((n) - 1))) - - - -static lua_Unsigned andaux (lua_State *L) { - int i, n = lua_gettop(L); - lua_Unsigned r = ~(lua_Unsigned)0; - for (i = 1; i <= n; i++) - r &= checkunsigned(L, i); - return trim(r); -} - - -static int b_and (lua_State *L) { - lua_Unsigned r = andaux(L); - pushunsigned(L, r); - return 1; -} - - -static int b_test (lua_State *L) { - lua_Unsigned r = andaux(L); - lua_pushboolean(L, r != 0); - return 1; -} - - -static int b_or (lua_State *L) { - int i, n = lua_gettop(L); - lua_Unsigned r = 0; - for (i = 1; i <= n; i++) - r |= checkunsigned(L, i); - pushunsigned(L, trim(r)); - return 1; -} - - -static int b_xor (lua_State *L) { - int i, n = lua_gettop(L); - lua_Unsigned r = 0; - for (i = 1; i <= n; i++) - r ^= checkunsigned(L, i); - pushunsigned(L, trim(r)); - return 1; -} - - -static int b_not (lua_State *L) { - lua_Unsigned r = ~checkunsigned(L, 1); - pushunsigned(L, trim(r)); - return 1; -} - - -static int b_shift (lua_State *L, lua_Unsigned r, lua_Integer i) { - if (i < 0) { /* shift right? */ - i = -i; - r = trim(r); - if (i >= LUA_NBITS) r = 0; - else r >>= i; - } - else { /* shift left */ - if (i >= LUA_NBITS) r = 0; - else r <<= i; - r = trim(r); - } - pushunsigned(L, r); - return 1; -} - - -static int b_lshift (lua_State *L) { - return b_shift(L, checkunsigned(L, 1), luaL_checkinteger(L, 2)); -} - - -static int b_rshift (lua_State *L) { - return b_shift(L, checkunsigned(L, 1), -luaL_checkinteger(L, 2)); -} - - -static int b_arshift (lua_State *L) { - lua_Unsigned r = checkunsigned(L, 1); - lua_Integer i = luaL_checkinteger(L, 2); - if (i < 0 || !(r & ((lua_Unsigned)1 << (LUA_NBITS - 1)))) - return b_shift(L, r, -i); - else { /* arithmetic shift for 'negative' number */ - if (i >= LUA_NBITS) r = ALLONES; - else - r = trim((r >> i) | ~(trim(~(lua_Unsigned)0) >> i)); /* add signal bit */ - pushunsigned(L, r); - return 1; - } -} - - -static int b_rot (lua_State *L, lua_Integer d) { - lua_Unsigned r = checkunsigned(L, 1); - int i = d & (LUA_NBITS - 1); /* i = d % NBITS */ - r = trim(r); - if (i != 0) /* avoid undefined shift of LUA_NBITS when i == 0 */ - r = (r << i) | (r >> (LUA_NBITS - i)); - pushunsigned(L, trim(r)); - return 1; -} - - -static int b_lrot (lua_State *L) { - return b_rot(L, luaL_checkinteger(L, 2)); -} - - -static int b_rrot (lua_State *L) { - return b_rot(L, -luaL_checkinteger(L, 2)); -} - - -/* -** get field and width arguments for field-manipulation functions, -** checking whether they are valid. -** ('luaL_error' called without 'return' to avoid later warnings about -** 'width' being used uninitialized.) -*/ -static int fieldargs (lua_State *L, int farg, int *width) { - lua_Integer f = luaL_checkinteger(L, farg); - lua_Integer w = luaL_optinteger(L, farg + 1, 1); - luaL_argcheck(L, 0 <= f, farg, "field cannot be negative"); - luaL_argcheck(L, 0 < w, farg + 1, "width must be positive"); - if (f + w > LUA_NBITS) - luaL_error(L, "trying to access non-existent bits"); - *width = (int)w; - return (int)f; -} - - -static int b_extract (lua_State *L) { - int w; - lua_Unsigned r = trim(checkunsigned(L, 1)); - int f = fieldargs(L, 2, &w); - r = (r >> f) & mask(w); - pushunsigned(L, r); - return 1; -} - - -static int b_replace (lua_State *L) { - int w; - lua_Unsigned r = trim(checkunsigned(L, 1)); - lua_Unsigned v = trim(checkunsigned(L, 2)); - int f = fieldargs(L, 3, &w); - lua_Unsigned m = mask(w); - r = (r & ~(m << f)) | ((v & m) << f); - pushunsigned(L, r); - return 1; -} - - -static const luaL_Reg bitlib[] = { - {"arshift", b_arshift}, - {"band", b_and}, - {"bnot", b_not}, - {"bor", b_or}, - {"bxor", b_xor}, - {"btest", b_test}, - {"extract", b_extract}, - {"lrotate", b_lrot}, - {"lshift", b_lshift}, - {"replace", b_replace}, - {"rrotate", b_rrot}, - {"rshift", b_rshift}, - {NULL, NULL} -}; - - - -LUAMOD_API int luaopen_bit32 (lua_State *L) { - luaL_newlib(L, bitlib); - return 1; -} - - -#else /* }{ */ - - -LUAMOD_API int luaopen_bit32 (lua_State *L) { - return luaL_error(L, "library 'bit32' has been deprecated"); -} - -#endif /* } */ |