diff options
Diffstat (limited to 'lua/lbitlib.c')
| -rw-r--r-- | lua/lbitlib.c | 111 |
1 files changed, 66 insertions, 45 deletions
diff --git a/lua/lbitlib.c b/lua/lbitlib.c index 31c7b66..1cb1d5b 100644 --- a/lua/lbitlib.c +++ b/lua/lbitlib.c @@ -1,5 +1,5 @@ /* -** $Id: lbitlib.c,v 1.18.1.2 2013/07/09 18:01:41 roberto Exp $ +** $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 */ @@ -7,20 +7,36 @@ #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) @@ -29,28 +45,25 @@ #define mask(n) (~((ALLONES << 1) << ((n) - 1))) -typedef lua_Unsigned b_uint; - - -static b_uint andaux (lua_State *L) { +static lua_Unsigned andaux (lua_State *L) { int i, n = lua_gettop(L); - b_uint r = ~(b_uint)0; + lua_Unsigned r = ~(lua_Unsigned)0; for (i = 1; i <= n; i++) - r &= luaL_checkunsigned(L, i); + r &= checkunsigned(L, i); return trim(r); } static int b_and (lua_State *L) { - b_uint r = andaux(L); - lua_pushunsigned(L, r); + lua_Unsigned r = andaux(L); + pushunsigned(L, r); return 1; } static int b_test (lua_State *L) { - b_uint r = andaux(L); + lua_Unsigned r = andaux(L); lua_pushboolean(L, r != 0); return 1; } @@ -58,32 +71,32 @@ static int b_test (lua_State *L) { static int b_or (lua_State *L) { int i, n = lua_gettop(L); - b_uint r = 0; + lua_Unsigned r = 0; for (i = 1; i <= n; i++) - r |= luaL_checkunsigned(L, i); - lua_pushunsigned(L, trim(r)); + r |= checkunsigned(L, i); + pushunsigned(L, trim(r)); return 1; } static int b_xor (lua_State *L) { int i, n = lua_gettop(L); - b_uint r = 0; + lua_Unsigned r = 0; for (i = 1; i <= n; i++) - r ^= luaL_checkunsigned(L, i); - lua_pushunsigned(L, trim(r)); + r ^= checkunsigned(L, i); + pushunsigned(L, trim(r)); return 1; } static int b_not (lua_State *L) { - b_uint r = ~luaL_checkunsigned(L, 1); - lua_pushunsigned(L, trim(r)); + lua_Unsigned r = ~checkunsigned(L, 1); + pushunsigned(L, trim(r)); return 1; } -static int b_shift (lua_State *L, b_uint r, int i) { +static int b_shift (lua_State *L, lua_Unsigned r, lua_Integer i) { if (i < 0) { /* shift right? */ i = -i; r = trim(r); @@ -95,54 +108,54 @@ static int b_shift (lua_State *L, b_uint r, int i) { else r <<= i; r = trim(r); } - lua_pushunsigned(L, r); + pushunsigned(L, r); return 1; } static int b_lshift (lua_State *L) { - return b_shift(L, luaL_checkunsigned(L, 1), luaL_checkint(L, 2)); + return b_shift(L, checkunsigned(L, 1), luaL_checkinteger(L, 2)); } static int b_rshift (lua_State *L) { - return b_shift(L, luaL_checkunsigned(L, 1), -luaL_checkint(L, 2)); + return b_shift(L, checkunsigned(L, 1), -luaL_checkinteger(L, 2)); } static int b_arshift (lua_State *L) { - b_uint r = luaL_checkunsigned(L, 1); - int i = luaL_checkint(L, 2); - if (i < 0 || !(r & ((b_uint)1 << (LUA_NBITS - 1)))) + 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) | ~(~(b_uint)0 >> i)); /* add signal bit */ - lua_pushunsigned(L, r); + r = trim((r >> i) | ~(trim(~(lua_Unsigned)0) >> i)); /* add signal bit */ + pushunsigned(L, r); return 1; } } -static int b_rot (lua_State *L, int i) { - b_uint r = luaL_checkunsigned(L, 1); - i &= (LUA_NBITS - 1); /* i = i % NBITS */ +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)); - lua_pushunsigned(L, trim(r)); + pushunsigned(L, trim(r)); return 1; } static int b_lrot (lua_State *L) { - return b_rot(L, luaL_checkint(L, 2)); + return b_rot(L, luaL_checkinteger(L, 2)); } static int b_rrot (lua_State *L) { - return b_rot(L, -luaL_checkint(L, 2)); + return b_rot(L, -luaL_checkinteger(L, 2)); } @@ -153,36 +166,35 @@ static int b_rrot (lua_State *L) { ** 'width' being used uninitialized.) */ static int fieldargs (lua_State *L, int farg, int *width) { - int f = luaL_checkint(L, farg); - int w = luaL_optint(L, farg + 1, 1); + 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 = w; - return f; + *width = (int)w; + return (int)f; } static int b_extract (lua_State *L) { int w; - b_uint r = luaL_checkunsigned(L, 1); + lua_Unsigned r = trim(checkunsigned(L, 1)); int f = fieldargs(L, 2, &w); r = (r >> f) & mask(w); - lua_pushunsigned(L, r); + pushunsigned(L, r); return 1; } static int b_replace (lua_State *L) { int w; - b_uint r = luaL_checkunsigned(L, 1); - b_uint v = luaL_checkunsigned(L, 2); + lua_Unsigned r = trim(checkunsigned(L, 1)); + lua_Unsigned v = trim(checkunsigned(L, 2)); int f = fieldargs(L, 3, &w); - int m = mask(w); - v &= m; /* erase bits outside given width */ - r = (r & ~(m << f)) | (v << f); - lua_pushunsigned(L, r); + lua_Unsigned m = mask(w); + r = (r & ~(m << f)) | ((v & m) << f); + pushunsigned(L, r); return 1; } @@ -210,3 +222,12 @@ LUAMOD_API int luaopen_bit32 (lua_State *L) { return 1; } + +#else /* }{ */ + + +LUAMOD_API int luaopen_bit32 (lua_State *L) { + return luaL_error(L, "library 'bit32' has been deprecated"); +} + +#endif /* } */ |