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authorSteven Barth <steven@midlink.org>2009-04-21 16:26:45 +0000
committerSteven Barth <steven@midlink.org>2009-04-21 16:26:45 +0000
commita2b916ab736802050b19562b7c163e3f3bb1566f (patch)
treed35b68f7bcac43f66f4cdb915ef327b76856594b /libs/nixio/src/bit.c
parent085a0a9ec040fc3ea5ee537d2cee724aa775747b (diff)
Merge nixio 0.2
Diffstat (limited to 'libs/nixio/src/bit.c')
-rw-r--r--libs/nixio/src/bit.c125
1 files changed, 125 insertions, 0 deletions
diff --git a/libs/nixio/src/bit.c b/libs/nixio/src/bit.c
new file mode 100644
index 000000000..14fdecab1
--- /dev/null
+++ b/libs/nixio/src/bit.c
@@ -0,0 +1,125 @@
+/*
+ * nixio - Linux I/O library for lua
+ *
+ * Copyright (C) 2009 Steven Barth <steven@midlink.org>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "nixio.h"
+#include <stdint.h>
+#include <stdlib.h>
+
+/* 52 bit maximum precision */
+#define NIXIO_BIT_BMAX 52
+#define NIXIO_BIT_NMAX 0xfffffffffffff
+
+#define NIXIO_BIT_XOP(BIT_XOP) \
+ uint64_t oper = luaL_checknumber(L, 1); \
+ const int args = lua_gettop(L); \
+ \
+ for (int i = 2; i <= args; i++) { \
+ uint64_t oper2 = luaL_checknumber(L, i); \
+ oper BIT_XOP oper2; \
+ } \
+ \
+ lua_pushnumber(L, oper); \
+ return 1; \
+
+
+static int nixio_bit_or(lua_State *L) {
+ NIXIO_BIT_XOP(|=);
+}
+
+static int nixio_bit_and(lua_State *L) {
+ NIXIO_BIT_XOP(&=);
+}
+
+static int nixio_bit_xor(lua_State *L) {
+ NIXIO_BIT_XOP(^=);
+}
+
+static int nixio_bit_unset(lua_State *L) {
+ NIXIO_BIT_XOP(&= ~);
+}
+
+static int nixio_bit_not(lua_State *L) {
+ lua_pushnumber(L, (~((uint64_t)luaL_checknumber(L, 1))) & NIXIO_BIT_NMAX);
+ return 1;
+}
+
+static int nixio_bit_shl(lua_State *L) {
+ uint64_t oper = luaL_checknumber(L, 1);
+ oper <<= luaL_checkinteger(L, 2);
+ if (oper > NIXIO_BIT_NMAX) {
+ return luaL_error(L, "arithmetic overflow");
+ } else {
+ lua_pushnumber(L, oper);
+ return 1;
+ }
+}
+
+static int nixio_bit_ashr(lua_State *L) {
+ int64_t oper = luaL_checknumber(L, 1);
+ lua_pushnumber(L, oper >> luaL_checkinteger(L, 2));
+ return 1;
+}
+
+static int nixio_bit_shr(lua_State *L) {
+ uint64_t oper = luaL_checknumber(L, 1);
+ lua_pushnumber(L, oper >> luaL_checkinteger(L, 2));
+ return 1;
+}
+
+static int nixio_bit_div(lua_State *L) {
+ NIXIO_BIT_XOP(/=);
+}
+
+static int nixio_bit_check(lua_State *L) {
+ uint64_t oper = luaL_checknumber(L, 1);
+ uint64_t oper2 = luaL_checknumber(L, 2);
+ lua_pushboolean(L, (oper & oper2) == oper2);
+ return 1;
+}
+
+static int nixio_bit_cast(lua_State *L) {
+ lua_pushnumber(L, ((uint64_t)luaL_checknumber(L, 1)) & NIXIO_BIT_NMAX);
+ return 1;
+}
+
+/* module table */
+static const luaL_reg R[] = {
+ {"bor", nixio_bit_or},
+ {"set", nixio_bit_or},
+ {"band", nixio_bit_and},
+ {"bxor", nixio_bit_xor},
+ {"unset", nixio_bit_unset},
+ {"bnot", nixio_bit_not},
+ {"rshift", nixio_bit_shr},
+ {"arshift", nixio_bit_ashr},
+ {"lshift", nixio_bit_shl},
+ {"div", nixio_bit_div},
+ {"check", nixio_bit_check},
+ {"cast", nixio_bit_cast},
+ {NULL, NULL}
+};
+
+void nixio_open_bit(lua_State *L) {
+ lua_newtable(L);
+ luaL_register(L, NULL, R);
+ lua_pushnumber(L, NIXIO_BIT_BMAX);
+ lua_setfield(L, -2, "bits");
+ lua_pushnumber(L, NIXIO_BIT_NMAX);
+ lua_setfield(L, -2, "max");
+ lua_setfield(L, -2, "bit");
+}