56 lines
1.3 KiB
C++
56 lines
1.3 KiB
C++
// Copyright (c) Vitaliy Filippov, 2019+
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// License: VNPL-1.1 (see README.md for details)
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#include "base64.h"
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std::string base64_encode(const std::string &in)
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{
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std::string out;
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unsigned val = 0;
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int valb = -6;
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for (unsigned char c: in)
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{
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val = (val << 8) + c;
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valb += 8;
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while (valb >= 0)
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{
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out.push_back("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"[(val>>valb) & 0x3F]);
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valb -= 6;
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}
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}
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if (valb > -6)
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out.push_back("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"[((val<<8)>>(valb+8)) & 0x3F]);
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while (out.size() % 4)
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out.push_back('=');
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return out;
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}
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static char T[256] = { 0 };
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std::string base64_decode(const std::string &in)
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{
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std::string out;
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if (T[0] == 0)
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{
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for (int i = 0; i < 256; i++)
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T[i] = -1;
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for (int i = 0; i < 64; i++)
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T[(unsigned char)("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"[i])] = i;
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}
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unsigned val = 0;
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int valb = -8;
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for (unsigned char c: in)
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{
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if (T[c] == -1)
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break;
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val = (val<<6) + T[c];
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valb += 6;
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if (valb >= 0)
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{
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out.push_back(char((val >> valb) & 0xFF));
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valb -= 8;
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}
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}
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return out;
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}
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