commit af512ad6da83f75b9e764ceeba28198e6e842377
parent d27108ccd543049bd2006aa16ed74f8c4d899731
Author: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Thu, 11 Feb 2010 13:55:05 -0200
use of 'conventional' names for shift and rotate operations +
right/left versions for them
Diffstat:
M | lbitlib.c | | | 34 | +++++++++++++++++++++++++++------- |
1 file changed, 27 insertions(+), 7 deletions(-)
diff --git a/lbitlib.c b/lbitlib.c
@@ -1,5 +1,5 @@
/*
-** $Id: lbitlib.c,v 1.2 2009/11/24 12:05:44 roberto Exp roberto $
+** $Id: lbitlib.c,v 1.3 2010/01/12 19:40:02 roberto Exp roberto $
** Standard library for bitwise operations
** See Copyright Notice in lua.h
*/
@@ -80,9 +80,8 @@ static int b_not (lua_State *L) {
}
-static int b_shift (lua_State *L) {
+static int b_shift (lua_State *L, int i) {
b_uint r = getuintarg(L, 1);
- lua_Integer i = luaL_checkinteger(L, 2);
if (i < 0) { /* shift right? */
i = -i;
if (i >= NBITS) r = 0;
@@ -97,9 +96,18 @@ static int b_shift (lua_State *L) {
}
-static int b_rotate (lua_State *L) {
+static int b_lshift (lua_State *L) {
+ return b_shift(L, luaL_checkint(L, 2));
+}
+
+
+static int b_rshift (lua_State *L) {
+ return b_shift(L, -luaL_checkint(L, 2));
+}
+
+
+static int b_rot (lua_State *L, int i) {
b_uint r = getuintarg(L, 1);
- lua_Integer i = luaL_checkinteger(L, 2);
i &= (NBITS - 1); /* i = i % NBITS */
r = (r << i) | (r >> (NBITS - i));
lua_pushnumber(L, lua_uint2number(r));
@@ -107,14 +115,26 @@ static int b_rotate (lua_State *L) {
}
+static int b_rol (lua_State *L) {
+ return b_rot(L, luaL_checkint(L, 2));
+}
+
+
+static int b_ror (lua_State *L) {
+ return b_rot(L, -luaL_checkint(L, 2));
+}
+
+
static const luaL_Reg bitlib[] = {
{"band", b_and},
{"btest", b_test},
{"bor", b_or},
{"bxor", b_xor},
{"bnot", b_not},
- {"bshift", b_shift},
- {"brotate", b_rotate},
+ {"lshift", b_lshift},
+ {"rshift", b_rshift},
+ {"rol", b_rol},
+ {"ror", b_ror},
{NULL, NULL}
};