linux c++ url和base64编解码

#include "codec.h" const static char BASE64ENPAD = '='; const static char BASE64ENMAP[64] = { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/' }; const static char BASE64DEMAP[128] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 62, 0, 0, 0, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 0, 0, 0, 61, 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 0, 0, 0, 0, 0, 0, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 0, 0, 0, 0, 0 }; static unsigned char encode0(char c0) { return ((c0 >> 2) & 0x3F); } static unsigned char encode1(char c0, char c1) { return ((c0 & 0x03) << 4) | ((c1 & 0xF0) >> 4); } static unsigned char encode2(char c1, char c2) { return ((c1 & 0x0F) << 2) | ((c2 & 0xC0) >> 6); } static unsigned char encode3(char c2) { return (c2 & 0x3F); } static char decode0(char c0, char c1) { return (c0 << 2) | (c1 >> 4); } static char decode1(char c1, char c2) { return (c1 << 4) | (c2 >> 2); } static char decode2(char c2, char c3) { return (c2 << 6) | (c3); } string base64_encode(const string& src) { int m = 0; int n = 0; string dst; char c0, c1, c2; m = src.size() / 3; n = src.size() % 3; for(int i = 0; i < m; i++) { c0 = src[i*3 + 0]; c1 = src[i*3 + 1]; c2 = src[i*3 + 2]; dst.push_back(BASE64ENMAP[encode0(c0)]); dst.push_back(BASE64ENMAP[encode1(c0, c1)]); dst.push_back(BASE64ENMAP[encode2(c1, c2)]); dst.push_back(BASE64ENMAP[encode3(c2)]); } switch(n) { case 1: c0 = src[m*3 + 0]; dst.push_back(BASE64ENMAP[encode0(c0)]); dst.push_back(BASE64ENMAP[encode1(c0, 0)]); dst.push_back(BASE64ENPAD); dst.push_back(BASE64ENPAD); break; case 2: c0 = src[m*3 + 0]; c1 = src[m*3 + 1]; dst.push_back(BASE64ENMAP[encode0(c0)]); dst.push_back(BASE64ENMAP[encode1(c0, c1)]); dst.push_back(BASE64ENMAP[encode2(c1, 0)]); dst.push_back(BASE64ENPAD); break; case 0: default: break; } return dst; } string base64_decode(const string& src) { string dst; char c0, c1, c2, c3; int size = src.size(); for(int i = 0; i < size; i+=4) { c0 = BASE64DEMAP[(unsigned char)src[i + 0]]; c1 = BASE64DEMAP[(unsigned char)src[i + 1]]; c2 = BASE64DEMAP[(unsigned char)src[i + 2]]; c3 = BASE64DEMAP[(unsigned char)src[i + 3]]; dst.push_back(decode0(c0, c1)); if('=' == c2) { break; } dst.push_back(decode1(c1, c2)); if('=' == c3) { break; } dst.push_back(decode2(c2, c3)); } return dst; } #ifdef _TEST_CODEC_BASE64 int main() { string src = "BASE64加密解密"; string dst = base64_encode(src); cout << src << endl; cout << dst << endl; cout << base64_decode(dst) << endl; } #endif