base64和quoted编码，解码的源码

/* * Copyright (c) 2008-2010 Sinosoft Ltd. * All rights reserved. * * Author: Jianou Zhang * */ #include <stdlib.h> #include <stdio.h> #include <string.h> #include <ctype.h> #include <time.h> #include "public_interface.h" char *strestr(char *str, char *substr, int sublen) { char *pos; char *dst = NULL; pos = str; while (pos = strstr(pos, substr)) { dst = pos; pos += sublen; } return dst; } char *strlstr(char *str, int strlen, char *substr, int sublen) { char *pos; int length; pos = strstr(str, substr); if (pos == NULL) return NULL; length = pos - str + sublen; if (length > strlen) return NULL; return pos; } static unsigned int str_chr(char *s, int c) { char ch; char *t; ch = c; t = s; while (1) { if (!*t) break; if (*t == ch) break; ++t; } return t - s; } int base64_encoding(char *in, int inLen, char *out, int *outlen) { unsigned char a, b, c; int i; char *s; int count = 0; if (inLen == 0) { *out = '\0'; return 0; } //inLen / 3 * 4 + 4; s = out; for (i = 0; i < inLen; i += 3) { a = in[i]; b = i + 1 < inLen ? in[i + 1] : 0; c = i + 2 < inLen ? in[i + 2] : 0; *s++ = b64alpha[a >> 2]; *s++ = b64alpha[((a & 3 ) << 4) | (b >> 4)]; if (i + 1 >= inLen) *s++ = B64PAD; else *s++ = b64alpha[((b & 15) << 2) | (c >> 6)]; if (i + 2 >= inLen) *s++ = B64PAD; else *s++ = b64alpha[c & 63]; count += 4; if (count == 128) { count = 0; *s++ = '\r'; *s++ = '\n'; } } if (count != 0) { *s++ = '\r'; *s++ = '\n'; } out[s - out]= '\0'; *outlen = strlen(out); return 0; } int base64_decoding(char *in, int inlen, char *out, int *outLen) { int i, j; unsigned char a[4]; unsigned char b[3]; char *s; if (inlen == 0) { *out='\0'; *outLen =0; return 0; } s = out; for (i = 0; i < inlen; i += 4) { for (j = 0; j < 4; j++) { if ((i + j) < inlen && in[i + j] != B64PAD) { a[j] = str_chr(b64alpha, in[i + j]); if (a[j] > 63) return 1; } else { a[j] = 0; } } b[0] = (a[0] << 2) | (a[1] >> 4); b[1] = (a[1] << 4) | (a[2] >> 2); b[2] = (a[2] << 6) | (a[3]); *s++ = b[0]; if (in[i + 1] == B64PAD) break; *s++ = b[1]; if (in[i + 2] == B64PAD) break; *s++ = b[2]; } *outLen = s - out; while ( *(outLen) && !out[*outLen - 1]) --(*outLen); return 0; } int quoted_encoding(const unsigned char* in, char* out, int inlen, int max_line_length) { int outlen = 0; int line_length = 0; int i; for (i = 0; i < inlen; i++, in++) { if ((*in >= '!') && (*in <= '~') && (*in != '=')) { *out++ = (char)*in; outlen++; line_length++; } else { sprintf(out, "=%02X", *in); out += 3; outlen += 3; line_length += 3; } if (line_length >= max_line_length - 3) { sprintf(out, "=\r\n"); out += 3; outlen += 3; line_length = 0; } } *out = '\0'; return outlen; } int quoted_decoding(const char* in, unsigned char* out, int inlen) { int outlen = 0; int i = 0; while (i < inlen) { if (strncmp(in, "=\r\n", 3) == 0) { in += 3; i += 3; } else { if (*in == '=') { sscanf(in, "=%02X", out); out++; in += 3; i += 3; } else { *out++ = (unsigned char)*in++; i++; } outlen++; } } *out = '\0'; return outlen; } void write_file(char *buf, int len, int recv, int send) { FILE *file; char buffer[256]; sprintf(buffer, "%d_to_%d_http.log", recv, send); if ((file = fopen(buffer, "ab+")) == NULL) { printf("open file failed\n"); return; } fwrite(buf, len, 1, file); fclose(file); } void write_log(char *buf, int len, const char *path) { FILE *file; time_t local_time; struct tm *current_time = NULL; char write_time[256] = {0}; if ((file = fopen(path, "ab+")) == NULL) { printf("open log file failed\n"); return; } time(&local_time); current_time = localtime(&local_time); sprintf( write_time, "%04d/%02d/%02d %02d:%02d:%02d: ", current_time->tm_year + 1900, current_time->tm_mon + 1, current_time->tm_mday, current_time->tm_hour, current_time->tm_min, current_time->tm_sec); fwrite(write_time, strlen(write_time), 1, file); fwrite(buf, len, 1, file); fclose(file); } int read_file(char *dst, char *path, int is_base64) { FILE *file; int length; char *buffer; int outlen; if ((file = fopen(path, "rb")) == NULL) return 0; fseek(file, 0, SEEK_END); length = ftell(file); fseek(file, 0, SEEK_SET); if (is_base64) { buffer = (char *)malloc(FILE_SIZE); if (buffer == NULL) return 0; fread(buffer, length, 1, file); base64_encoding(buffer, length, dst, &outlen); } else fread(dst, length, 1, file); fclose(file); return 1; }