base64编解码的另外几个版本
#include "crypto/encode/base64.h" static const std::string base64_chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZ" "abcdefghijklmnopqrstuvwxyz" "0123456789+/"; static inline bool is_base64(unsigned char c) { return (isalnum(c) || (c == '+') || (c == '/')); } std::string Base64::Encode(const std::string& src) { std::string ret; unsigned char char_array_3[3]; unsigned char char_array_4[4]; size_t srcLen = src.length(); const char* pSrc = src.c_str(); size_t i = 0; while (srcLen--) { char_array_3[i++] = *(pSrc++); if (i == 3) { char_array_4[0] = (char_array_3[0] & 0xfc) >> 2; char_array_4[1] = ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4); char_array_4[2] = ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6); char_array_4[3] = char_array_3[2] & 0x3f; for (i = 0; (i <4); i++) ret += base64_chars[char_array_4[i]]; i = 0; } } size_t j = 0; if (i) { for (j = i; j < 3; j++) char_array_3[j] = '\0'; char_array_4[0] = (char_array_3[0] & 0xfc) >> 2; char_array_4[1] = ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4); char_array_4[2] = ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6); char_array_4[3] = char_array_3[2] & 0x3f; for (j = 0; (j < i + 1); j++) ret += base64_chars[char_array_4[j]]; while ((i++ < 3)) ret += '='; } return ret; } std::string Base64::Encode(const unsigned char* src, size_t dataLen) { if ((src == NULL) || (dataLen == 0)) { return std::string(); } std::string ret; unsigned char char_array_3[3]; unsigned char char_array_4[4]; size_t srcLen = dataLen; const char* pSrc = reinterpret_cast<const char*>(src); size_t i = 0; while (srcLen--) { char_array_3[i++] = *(pSrc++); if (i == 3) { char_array_4[0] = (char_array_3[0] & 0xfc) >> 2; char_array_4[1] = ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4); char_array_4[2] = ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6); char_array_4[3] = char_array_3[2] & 0x3f; for (i = 0; (i <4); i++) ret += base64_chars[char_array_4[i]]; i = 0; } } size_t j = 0; if (i) { for (j = i; j < 3; j++) char_array_3[j] = '\0'; char_array_4[0] = (char_array_3[0] & 0xfc) >> 2; char_array_4[1] = ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4); char_array_4[2] = ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6); char_array_4[3] = char_array_3[2] & 0x3f; for (j = 0; (j < i + 1); j++) ret += base64_chars[char_array_4[j]]; while ((i++ < 3)) ret += '='; } return ret; } bool Base64::Decode(const std::string& src, std::string& out) { out.clear(); size_t in_len = src.size(); size_t i = 0; size_t j = 0; size_t in_ = 0; unsigned char char_array_4[4], char_array_3[3]; while (in_len-- && (src[in_] != '=') && is_base64(src[in_])) { char_array_4[i++] = src[in_]; in_++; if (i == 4) { for (i = 0; i <4; i++) char_array_4[i] = (unsigned char)base64_chars.find(char_array_4[i]); char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4); char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2); char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3]; for (i = 0; (i < 3); i++) out += char_array_3[i]; i = 0; } } if (i) { for (j = i; j <4; j++) char_array_4[j] = 0; for (j = 0; j <4; j++) char_array_4[j] = (unsigned char)base64_chars.find(char_array_4[j]); char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4); char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2); char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3]; for (j = 0; (j < i - 1); j++) out += char_array_3[j]; } return true; } bool Base64::Decode(const unsigned char* src, size_t srcLen, unsigned char* decoded, size_t& decoded_length) { if ((src == NULL) || (srcLen < 1)) return false; if ((decoded == NULL) || (decoded_length < 1)) return false; size_t i = 0; size_t j = 0; size_t in_ = 0; unsigned char char_array_4[4]; unsigned char char_array_3[3]; size_t offset = 0; while (srcLen-- && (src[in_] != '=') && is_base64(src[in_])) { char_array_4[i++] = src[in_]; in_++; if (i == 4) { for (i = 0; i <4; i++) char_array_4[i] = (unsigned char)base64_chars.find(char_array_4[i]); char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4); char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2); char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3]; for (i = 0; i < 3; i++) { if (offset < decoded_length) decoded[offset++] = char_array_3[i]; else return false; } i = 0; } } if (i) { for (j = i; j <4; j++) char_array_4[j] = 0; for (j = 0; j <4; j++) char_array_4[j] = (unsigned char)base64_chars.find(char_array_4[j]); char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4); char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2); char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3]; for (j = 0; (j < i - 1); j++) { if (offset < decoded_length) decoded[offset++] = char_array_3[j]; else return false; } } decoded_length = offset; return true; } bool Base64::Decode(const unsigned char* src, size_t srcLen, std::vector<unsigned char>& out) { out.clear(); size_t i = 0; size_t j = 0; size_t in_ = 0; unsigned char char_array_4[4]; unsigned char char_array_3[3]; while (srcLen-- && (src[in_] != '=') && is_base64(src[in_])) { char_array_4[i++] = src[in_]; in_++; if (i == 4) { for (i = 0; i <4; i++) char_array_4[i] = (unsigned char)base64_chars.find(char_array_4[i]); char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4); char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2); char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3]; for (i = 0; (i < 3); i++) out.push_back(char_array_3[i]); i = 0; } } if (i) { for (j = i; j <4; j++) char_array_4[j] = 0; for (j = 0; j <4; j++) char_array_4[j] = (unsigned char)base64_chars.find(char_array_4[j]); char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4); char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2); char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3]; for (j = 0; (j < i - 1); j++) out.push_back(char_array_3[j]); } return true; }