[nixio] implement hextonum and numtohex in C

This commit is contained in:
Bart Van Der Meerssche 2011-01-10 14:50:10 +01:00
parent 7c3ad70ff2
commit aa412d1dc4
3 changed files with 62 additions and 524 deletions

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@ -1,517 +0,0 @@
--[[
/*
* Copyright (c) 2007 Tim Kelly/Dialectronics
*
* 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.
*/
--]]
module(..., package.seeall);
local hex2bin = {
["0"] = "0000",
["1"] = "0001",
["2"] = "0010",
["3"] = "0011",
["4"] = "0100",
["5"] = "0101",
["6"] = "0110",
["7"] = "0111",
["8"] = "1000",
["9"] = "1001",
["a"] = "1010",
["b"] = "1011",
["c"] = "1100",
["d"] = "1101",
["e"] = "1110",
["f"] = "1111"
}
local bin2hex = {
["0000"] = "0",
["0001"] = "1",
["0010"] = "2",
["0011"] = "3",
["0100"] = "4",
["0101"] = "5",
["0110"] = "6",
["0111"] = "7",
["1000"] = "8",
["1001"] = "9",
["1010"] = "A",
["1011"] = "B",
["1100"] = "C",
["1101"] = "D",
["1110"] = "E",
["1111"] = "F"
}
--[[
local dec2hex = {
["0"] = "0",
["1"] = "1",
["2"] = "2",
["3"] = "3",
["4"] = "4",
["5"] = "5",
["6"] = "6",
["7"] = "7",
["8"] = "8",
["9"] = "9",
["10"] = "A",
["11"] = "B",
["12"] = "C",
["13"] = "D",
["14"] = "E",
["15"] = "F"
}
--]]
-- These functions are big-endian and take up to 32 bits
-- Hex2Bin
-- Bin2Hex
-- Hex2Dec
-- Dec2Hex
-- Bin2Dec
-- Dec2Bin
function Hex2Bin(s)
-- s -> hexadecimal string
local ret = ""
local i = 0
for i in string.gfind(s, ".") do
i = string.lower(i)
ret = ret..hex2bin[i]
end
return ret
end
function Bin2Hex(s)
-- s -> binary string
local l = 0
local h = ""
local b = ""
local rem
l = string.len(s)
rem = l % 4
l = l-1
h = ""
-- need to prepend zeros to eliminate mod 4
if (rem > 0) then
s = string.rep("0", 4 - rem)..s
end
for i = 1, l, 4 do
b = string.sub(s, i, i+3)
h = h..bin2hex[b]
end
return h
end
function Bin2Dec(s)
-- s -> binary string
local num = 0
local ex = string.len(s) - 1
local l = 0
l = ex + 1
for i = 1, l do
b = string.sub(s, i, i)
if b == "1" then
num = num + 2^ex
end
ex = ex - 1
end
return string.format("%u", num)
end
function Dec2Bin(s, num)
-- s -> Base10 string
-- num -> string length to extend to
local n
if (num == nil) then
n = 0
else
n = num
end
s = string.format("%x", s)
s = Hex2Bin(s)
while string.len(s) < n do
s = "0"..s
end
return s
end
function Hex2Dec(s)
-- s -> hexadecimal string
local s = Hex2Bin(s)
return Bin2Dec(s)
end
function Dec2Hex(s)
-- s -> Base10 string
s = string.format("%x", s)
return s
end
-- These functions are big-endian and will extend to 32 bits
-- BMAnd
-- BMNAnd
-- BMOr
-- BMXOr
-- BMNot
function BMAnd(v, m)
-- v -> hex string to be masked
-- m -> hex string mask
-- s -> hex string as masked
-- bv -> binary string of v
-- bm -> binary string mask
local bv = Hex2Bin(v)
local bm = Hex2Bin(m)
local i = 0
local s = ""
while (string.len(bv) < 32) do
bv = "0000"..bv
end
while (string.len(bm) < 32) do
bm = "0000"..bm
end
for i = 1, 32 do
cv = string.sub(bv, i, i)
cm = string.sub(bm, i, i)
if cv == cm then
if cv == "1" then
s = s.."1"
else
s = s.."0"
end
else
s = s.."0"
end
end
return Bin2Hex(s)
end
function BMNAnd(v, m)
-- v -> hex string to be masked
-- m -> hex string mask
-- s -> hex string as masked
-- bv -> binary string of v
-- bm -> binary string mask
local bv = Hex2Bin(v)
local bm = Hex2Bin(m)
local i = 0
local s = ""
while (string.len(bv) < 32) do
bv = "0000"..bv
end
while (string.len(bm) < 32) do
bm = "0000"..bm
end
for i = 1, 32 do
cv = string.sub(bv, i, i)
cm = string.sub(bm, i, i)
if cv == cm then
if cv == "1" then
s = s.."0"
else
s = s.."1"
end
else
s = s.."1"
end
end
return Bin2Hex(s)
end
function BMOr(v, m)
-- v -> hex string to be masked
-- m -> hex string mask
-- s -> hex string as masked
-- bv -> binary string of v
-- bm -> binary string mask
local bv = Hex2Bin(v)
local bm = Hex2Bin(m)
local i = 0
local s = ""
while (string.len(bv) < 32) do
bv = "0000"..bv
end
while (string.len(bm) < 32) do
bm = "0000"..bm
end
for i = 1, 32 do
cv = string.sub(bv, i, i)
cm = string.sub(bm, i, i)
if cv == "1" then
s = s.."1"
elseif cm == "1" then
s = s.."1"
else
s = s.."0"
end
end
return Bin2Hex(s)
end
function BMXOr(v, m)
-- v -> hex string to be masked
-- m -> hex string mask
-- s -> hex string as masked
-- bv -> binary string of v
-- bm -> binary string mask
local bv = Hex2Bin(v)
local bm = Hex2Bin(m)
local i = 0
local s = ""
while (string.len(bv) < 32) do
bv = "0000"..bv
end
while (string.len(bm) < 32) do
bm = "0000"..bm
end
for i = 1, 32 do
cv = string.sub(bv, i, i)
cm = string.sub(bm, i, i)
if cv == "1" then
if cm == "0" then
s = s.."1"
else
s = s.."0"
end
elseif cm == "1" then
if cv == "0" then
s = s.."1"
else
s = s.."0"
end
else
-- cv and cm == "0"
s = s.."0"
end
end
return Bin2Hex(s)
end
function BMNot(v, m)
-- v -> hex string to be masked
-- m -> hex string mask
-- s -> hex string as masked
-- bv -> binary string of v
-- bm -> binary string mask
local bv = Hex2Bin(v)
local bm = Hex2Bin(m)
local i = 0
local s = ""
while (string.len(bv) < 32) do
bv = "0000"..bv
end
while (string.len(bm) < 32) do
bm = "0000"..bm
end
for i = 1, 32 do
cv = string.sub(bv, i, i)
cm = string.sub(bm, i, i)
if cm == "1" then
if cv == "1" then
-- turn off
s = s.."0"
else
-- turn on
s = s.."1"
end
else
-- leave untouched
s = s..cv
end
end
return Bin2Hex(s)
end
-- these functions shift right and left, adding zeros to lost or gained bits
-- returned values are 32 bits long
-- BShRight(v, nb)
-- BShLeft(v, nb)
function BShRight(v, nb)
-- v -> hexstring value to be shifted
-- nb -> number of bits to shift to the right
-- s -> binary string of v
local s = Hex2Bin(v)
while (string.len(s) < 32) do
s = "0000"..s
end
s = string.sub(s, 1, 32 - nb)
while (string.len(s) < 32) do
s = "0"..s
end
return Bin2Hex(s)
end
function BShLeft(v, nb)
-- v -> hexstring value to be shifted
-- nb -> number of bits to shift to the right
-- s -> binary string of v
local s = Hex2Bin(v)
while (string.len(s) < 32) do
s = "0000"..s
end
s = string.sub(s, nb + 1, 32)
while (string.len(s) < 32) do
s = s.."0"
end
return Bin2Hex(s)
end

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@ -20,13 +20,12 @@
]]--
local nixio = require 'nixio'
local BinDecHex = require 'flukso.BinDecHex'
local os, table, string =
os, table, string
local getfenv, setmetatable, tonumber =
getfenv, setmetatable, tonumber
local getfenv, setmetatable =
getfenv, setmetatable
module (...)
local modenv = getfenv()
@ -132,7 +131,7 @@ function rx(msg, cdev)
msg.received.crc = msg.received.l:sub(-2, -1)
msg.received.l = msg.received.l:sub(1, -3)
if nixio.bin.dow_crc(msg.received.l) ~= tonumber(BinDecHex.Hex2Dec(msg.received.crc)) then
if nixio.bin.dow_crc(msg.received.l) ~= nixio.bin.hextonum(msg.received.crc) then
--> TODO implement crc error counter
msg.received.l = ''
end
@ -152,11 +151,11 @@ function decode(msg)
if msg.parsed[1] == 'gd' then
for i = 1, msg.decoded.largs:len() / 18 do
msg.decoded[(i-1)*3 + 1] =
tonumber(BinDecHex.Hex2Dec(msg.decoded.largs:sub((i-1)*18 + 1, (i-1)*18 + 2)))
nixio.bin.hextonum(msg.decoded.largs:sub((i-1)*18 + 1, (i-1)*18 + 2))
msg.decoded[(i-1)*3 + 2] =
tonumber(BinDecHex.Hex2Dec(msg.decoded.largs:sub((i-1)*18 + 3, (i-1)*18 + 10)))
nixio.bin.hextonum(msg.decoded.largs:sub((i-1)*18 + 3, (i-1)*18 + 10))
msg.decoded[(i-1)*3 + 3] =
tonumber(BinDecHex.Hex2Dec(msg.decoded.largs:sub((i-1)*18 + 11, (i-1)*18 + 18)))
nixio.bin.hextonum(msg.decoded.largs:sub((i-1)*18 + 11, (i-1)*18 + 18))
end
elseif msg.parsed[1] == 'gv' then

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@ -343,6 +343,60 @@ static int nixio_bin_b64decode(lua_State *L) {
return 1;
}
static int nixio_bin_hextonum(lua_State *L) {
size_t len;
uint32_t number = 0;
const char *hex = luaL_checklstring(L, 1, &len);
if (!((len == 2) | (len == 4) | (len == 8))) {
errno = EINVAL;
return nixio__perror(L);
}
for (size_t i = 0; i < len; i++) {
char c = hex[i];
number <<= 4; /* make room to shift-in next nibble */
if (c >= '0' && c <= '9') {
number |= c - '0';
}
else if (c >= 'a' && c <= 'f') {
number |= c - 'a' + 10;
}
else if (c >= 'A' && c <= 'F') {
number |= c - 'A' + 10;
}
else {
errno = EINVAL;
return nixio__perror(L);
}
}
nixio__pushnumber(L, number);
return 1;
}
static int nixio_bin_numtohex(lua_State *L) {
char hex[8];
uint32_t number = nixio__checknumber(L, 1);
size_t len = luaL_optinteger(L, 2, 4); /* default 4 bytes hex encoding */
if (!((len == 1) | (len == 2) | (len == 4))) {
errno = EINVAL;
return nixio__perror(L);
}
size_t lenout = len * 2;
for (size_t i = 0; i < lenout; i++) {
hex[lenout - 1 - i] = nixio__bin2hex[(number & 0x0f)];
number >>= 4;
}
lua_pushlstring(L, hex, lenout);
return 1;
}
/* module table */
static const luaL_reg R[] = {
{"hexlify", nixio_bin_hexlify},
@ -351,6 +405,8 @@ static const luaL_reg R[] = {
{"dow_crc", nixio_bin_dow_crc},
{"b64encode", nixio_bin_b64encode},
{"b64decode", nixio_bin_b64decode},
{"hextonum", nixio_bin_hextonum},
{"numtohex", nixio_bin_numtohex},
{NULL, NULL}
};