You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
100 lines
2.4 KiB
100 lines
2.4 KiB
/* Distributed under the OSI-approved BSD 3-Clause License. See accompanying
|
|
file Copyright.txt or https://cmake.org/licensing for details. */
|
|
#include "cmBase32.h"
|
|
|
|
// -- Static functions
|
|
|
|
static const unsigned char Base32EncodeTable[33] =
|
|
"ABCDEFGHIJKLMNOPQRSTUVWXYZ234567";
|
|
|
|
inline unsigned char Base32EncodeChar(int schar)
|
|
{
|
|
return Base32EncodeTable[schar];
|
|
}
|
|
|
|
void Base32Encode5(const unsigned char src[5], char dst[8])
|
|
{
|
|
// [0]:5 bits
|
|
dst[0] = Base32EncodeChar((src[0] >> 3) & 0x1F);
|
|
// [0]:3 bits + [1]:2 bits
|
|
dst[1] = Base32EncodeChar(((src[0] << 2) & 0x1C) + ((src[1] >> 6) & 0x03));
|
|
// [1]:5 bits
|
|
dst[2] = Base32EncodeChar((src[1] >> 1) & 0x1F);
|
|
// [1]:1 bit + [2]:4 bits
|
|
dst[3] = Base32EncodeChar(((src[1] << 4) & 0x10) + ((src[2] >> 4) & 0x0F));
|
|
// [2]:4 bits + [3]:1 bit
|
|
dst[4] = Base32EncodeChar(((src[2] << 1) & 0x1E) + ((src[3] >> 7) & 0x01));
|
|
// [3]:5 bits
|
|
dst[5] = Base32EncodeChar((src[3] >> 2) & 0x1F);
|
|
// [3]:2 bits + [4]:3 bit
|
|
dst[6] = Base32EncodeChar(((src[3] << 3) & 0x18) + ((src[4] >> 5) & 0x07));
|
|
// [4]:5 bits
|
|
dst[7] = Base32EncodeChar((src[4] << 0) & 0x1F);
|
|
}
|
|
|
|
// -- Class methods
|
|
|
|
cmBase32Encoder::cmBase32Encoder()
|
|
{
|
|
}
|
|
|
|
cmBase32Encoder::~cmBase32Encoder()
|
|
{
|
|
}
|
|
|
|
std::string cmBase32Encoder::encodeString(const unsigned char* input,
|
|
size_t len, bool padding)
|
|
{
|
|
std::string res;
|
|
|
|
static const size_t blockSize = 5;
|
|
static const size_t bufferSize = 8;
|
|
char buffer[bufferSize];
|
|
|
|
const unsigned char* end = input + len;
|
|
while ((input + blockSize) <= end) {
|
|
Base32Encode5(input, buffer);
|
|
res.append(buffer, bufferSize);
|
|
input += blockSize;
|
|
}
|
|
|
|
size_t remain = static_cast<size_t>(end - input);
|
|
if (remain != 0) {
|
|
// Temporary source buffer filled up with 0s
|
|
unsigned char extended[blockSize];
|
|
for (size_t ii = 0; ii != remain; ++ii) {
|
|
extended[ii] = input[ii];
|
|
}
|
|
for (size_t ii = remain; ii != blockSize; ++ii) {
|
|
extended[ii] = 0;
|
|
}
|
|
|
|
Base32Encode5(extended, buffer);
|
|
size_t numPad(0);
|
|
switch (remain) {
|
|
case 1:
|
|
numPad = 6;
|
|
break;
|
|
case 2:
|
|
numPad = 4;
|
|
break;
|
|
case 3:
|
|
numPad = 3;
|
|
break;
|
|
case 4:
|
|
numPad = 1;
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
res.append(buffer, bufferSize - numPad);
|
|
if (padding) {
|
|
for (size_t ii = 0; ii != numPad; ++ii) {
|
|
res.push_back(paddingChar);
|
|
}
|
|
}
|
|
}
|
|
|
|
return res;
|
|
}
|