base64.h

/******************************************************************** 文件名 : Base64.h 描 述 : Base64編碼，解碼 版 權 : 作 者 : 修改記錄:日期 修改人 修改內容2014-01-04 13:31 創建 ********************************************************************/ #ifndef BASE_BASE64_H_ #define BASE_BASE64_H_#ifdef __cplusplus extern "C" { #endif#define BASE64_BUF_TOO_SMALL -1 #define BASE64_INVALID_DATA -2/*** \brief Encode a buffer into base64 format** \param dst destination buffer* \param dlen size of the buffer* \param src source buffer* \param slen amount of data to be encoded** \return 0 if successful, or BASE64_BUF_TOO_SMALL.* *dlen is always updated to reflect the amount* of data that has (or would have) been written.** \note Call this function with *dlen = 0 to obtain the* required buffer size in *dlen*/ int base64_encode(unsigned char *dst, int *dlen, unsigned char *src, int slen);/*** \brief Decode a base64-formatted buffer** \param dst destination buffer* \param dlen size of the buffer* \param src source buffer* \param slen amount of data to be decoded** \return 0 if successful, BASE64_BUF_TOO_SMALL, or* BASE64_INVALID_DATA if the input data is not* correct. *dlen is always updated to reflect the amount* of data that has (or would have) been written.** \note Call this function with *dlen = 0 to obtain the* required buffer size in *dlen*/ int base64_decode(unsigned char *dst, int *dlen, unsigned char *src, int slen);#ifdef __cplusplus } #endif#endif

Base64.cpp

/******************************************************************** 文件名 : Base64.c 描 述 : Base64編碼，解碼 版 權 : 作 者 : 修改記錄:日期 修改人 修改內容2014-01-04 17:38 創建 ********************************************************************/ #include <string.h> #include <stdio.h> #include "stdafx.h" #include "Base64.h"//const char BASE64_CHARS_TABLE[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";static const unsigned char base64_enc_map[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', '+', '/' };static const unsigned char base64_dec_map[128] = {127, 127, 127, 127, 127, 127, 127, 127, 127, 127,127, 127, 127, 127, 127, 127, 127, 127, 127, 127,127, 127, 127, 127, 127, 127, 127, 127, 127, 127,127, 127, 127, 127, 127, 127, 127, 127, 127, 127,127, 127, 127, 62, 127, 127, 127, 63, 52, 53,54, 55, 56, 57, 58, 59, 60, 61, 127, 127,127, 64, 127, 127, 127, 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, 127, 127, 127, 127, 127, 127, 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, 127, 127, 127, 127, 127 };//Encode a buffer into base64 format int base64_encode(unsigned char *dst, int *dlen, unsigned char *src, int slen ){int i, n;int C1, C2, C3;unsigned char *p;if(slen == 0)return 0;n = (slen << 3) / 6;switch((slen << 3) - (n * 6)){case 2: n += 3; break;case 4: n += 2; break;default: break;}if(*dlen < n + 1){*dlen = n + 1;return BASE64_BUF_TOO_SMALL;}n = (slen / 3) * 3;for(i=0, p=dst; i<n; i += 3 ){C1 = *src++;C2 = *src++;C3 = *src++;*p++ = base64_enc_map[(C1 >> 2) & 0x3F];*p++ = base64_enc_map[(((C1 & 3) << 4) + (C2 >> 4)) & 0x3F];*p++ = base64_enc_map[(((C2 & 15) << 2) + (C3 >> 6)) & 0x3F];*p++ = base64_enc_map[C3 & 0x3F];}if(i < slen){C1 = *src++;C2 = ((i + 1) < slen) ? *src++ : 0;*p++ = base64_enc_map[(C1 >> 2) & 0x3F];*p++ = base64_enc_map[(((C1 & 3) << 4) + (C2 >> 4)) & 0x3F];if((i + 1) < slen)*p++ = base64_enc_map[((C2 & 15) << 2) & 0x3F];else *p++ = '=';*p++ = '=';}*dlen = p - dst;*p = 0;return 0; }//Decode a base64-formatted buffer int base64_decode(unsigned char *dst, int *dlen, unsigned char *src, int slen) {int i, j, n;unsigned long x;unsigned char *p;for(i=j=n=0; i < slen; i++){if((slen - i) >= 2 &&src[i] == '\r' && src[i + 1] == '\n')continue;if(src[i] == '\n')continue;if(src[i] == '=' && ++j > 2){return BASE64_INVALID_DATA;}if(src[i] > 127 || base64_dec_map[src[i]] == 127){return BASE64_INVALID_DATA;}if(base64_dec_map[src[i]] < 64 && j != 0){return BASE64_INVALID_DATA;}n++;}if(n == 0){return 0;}n = ((n * 6) + 7) >> 3;if(*dlen < n){*dlen = n;return BASE64_BUF_TOO_SMALL;}for(j=3, n=x=0, p=dst; i>0; i--, src++ ){if(*src == '\r' || *src == '\n')continue;j -= (base64_dec_map[*src] == 64);x = (x << 6) | (base64_dec_map[*src] & 0x3F);if(++n == 4){n = 0;if(j > 0) *p++ = (unsigned char)(x >> 16);if(j > 1) *p++ = (unsigned char)(x >> 8);if(j > 2) *p++ = (unsigned char)(x );}}*dlen = p - dst;return 0; } 《新程序員》：云原生和全面數字化實踐50位技術專家共同創作，文字、視頻、音頻交互閱讀

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