src/common/quoted-printable.c

   1 /*
   2  * Sylpheed -- a GTK+ based, lightweight, and fast e-mail client
   3  * Copyright (C) 1999-2007 Hiroyuki Yamamoto and the Claws Mail team
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  */
  19
  20 #include <glib.h>
  21 #include <ctype.h>
  22
  23 #include "utils.h"
  24
  25 #define MAX_LINELEN     76
  26
  27 #define IS_LBREAK(p) \
  28         (*(p) == '\0' || *(p) == '\n' || (*(p) == '\r' && *((p) + 1) == '\n'))
  29
  30 #define SOFT_LBREAK_IF_REQUIRED(n)                                      \
  31         if (len + (n) > MAX_LINELEN ||                                  \
  32             (len + (n) == MAX_LINELEN && (!IS_LBREAK(inp + 1)))) {      \
  33                 *outp++ = '=';                                          \
  34                 *outp++ = '\n';                                         \
  35                 len = 0;                                                \
  36         }
  37
  38 void qp_encode_line(gchar *out, const guchar *in)
  39 {
  40         const guchar *inp = in;
  41         gchar *outp = out;
  42         guchar ch;
  43         gint len = 0;
  44
  45         while (*inp != '\0') {
  46                 ch = *inp;
  47
  48                 if (IS_LBREAK(inp)) {
  49                         *outp++ = '\n';
  50                         len = 0;
  51                         if (*inp == '\r')
  52                                 inp++;
  53                         inp++;
  54                 } else if (ch == '\t' || ch == ' ') {
  55                         if (IS_LBREAK(inp + 1)) {
  56                                 SOFT_LBREAK_IF_REQUIRED(3);
  57                                 *outp++ = '=';
  58                                 get_hex_str(outp, ch);
  59                                 outp += 2;
  60                                 len += 3;
  61                                 inp++;
  62                         } else {
  63                                 SOFT_LBREAK_IF_REQUIRED(1);
  64                                 *outp++ = *inp++;
  65                                 len++;
  66                         }
  67                 } else if ((ch >= 33 && ch <= 60) || (ch >= 62 && ch <= 126)) {
  68                         SOFT_LBREAK_IF_REQUIRED(1);
  69                         *outp++ = *inp++;
  70                         len++;
  71                 } else {
  72                         SOFT_LBREAK_IF_REQUIRED(3);
  73                         *outp++ = '=';
  74                         get_hex_str(outp, ch);
  75                         outp += 2;
  76                         len += 3;
  77                         inp++;
  78                 }
  79         }
  80
  81         if (len > 0)
  82                 *outp++ = '\n';
  83
  84         *outp = '\0';
  85 }
  86
  87 gint qp_decode_line(gchar *str)
  88 {
  89         gchar *inp = str, *outp = str;
  90
  91         while (*inp != '\0') {
  92                 if (*inp == '=') {
  93                         if (inp[1] && inp[2] && inp[1] == '0' && inp[2] == '0') {
  94                                 inp += 3;
  95                                 continue;
  96                         } else if (inp[1] && inp[2] &&
  97                             get_hex_value((guchar *)outp, inp[1], inp[2])
  98                             == TRUE) {
  99                                 inp += 3;
 100                         } else if (inp[1] == '\0' || g_ascii_isspace(inp[1])) {
 101                                 /* soft line break */
 102                                 break;
 103                         } else {
 104                                 /* broken QP string */
 105                                 *outp = *inp++;
 106                         }
 107                 } else {
 108                         *outp = *inp++;
 109                 }
 110                 outp++;
 111         }
 112
 113         *outp = '\0';
 114
 115         return outp - str;
 116 }
 117
 118 gint qp_decode_const(gchar *out, gint avail, const gchar *str)
 119 {
 120         const gchar *inp = str;
 121         gchar *outp = out;
 122
 123         while (*inp != '\0' && avail > 0) {
 124                 if (*inp == '=') {
 125                         if (inp[1] && inp[2] && inp[1] == '0' && inp[2] == '0') {
 126                                 inp += 3;
 127                                 continue;
 128                         } else if (inp[1] && inp[2] &&
 129                             get_hex_value((guchar *)outp, inp[1], inp[2])
 130                             == TRUE) {
 131                                 inp += 3;
 132                         } else if (inp[1] == '\0' || g_ascii_isspace(inp[1])) {
 133                                 /* soft line break */
 134                                 break;
 135                         } else {
 136                                 /* broken QP string */
 137                                 *outp = *inp++;
 138                         }
 139                 } else {
 140                         *outp = *inp++;
 141                 }
 142                 outp++;
 143                 avail--;
 144         }
 145
 146         *outp = '\0';
 147
 148         return outp - out;
 149 }
 150
 151 gint qp_decode_q_encoding(guchar *out, const gchar *in, gint inlen)
 152 {
 153         const gchar *inp = in;
 154         guchar *outp = out;
 155
 156         if (inlen < 0)
 157                 inlen = G_MAXINT;
 158
 159         while (inp - in < inlen && *inp != '\0') {
 160                 if (*inp == '=' && inp + 3 - in <= inlen) {
 161                         if (inp[1] && inp[2] && inp[1] == '0' && inp[2] == '0') {
 162                                 inp += 3;
 163                                 continue;
 164                         } else if (get_hex_value(outp, inp[1], inp[2]) == TRUE) {
 165                                 inp += 3;
 166                         } else {
 167                                 *outp = *inp++;
 168                         }
 169                 } else if (*inp == '_') {
 170                         *outp = ' ';
 171                         inp++;
 172                 } else {
 173                         *outp = *inp++;
 174                 }
 175                 outp++;
 176         }
 177
 178         *outp = '\0';
 179
 180         return outp - out;
 181 }
 182
 183 gint qp_get_q_encoding_len(const guchar *str)
 184 {
 185         const guchar *inp = str;
 186         gint len = 0;
 187
 188         while (*inp != '\0') {
 189                 if (*inp == 0x20)
 190                         len++;
 191                 else if (*inp == '=' || *inp == '?' || *inp == '_' ||
 192                          *inp < 32 || *inp > 127 || g_ascii_isspace(*inp))
 193                         len += 3;
 194                 else
 195                         len++;
 196
 197                 inp++;
 198         }
 199
 200         return len;
 201 }
 202
 203 void qp_q_encode(gchar *out, const guchar *in)
 204 {
 205         const guchar *inp = in;
 206         gchar *outp = out;
 207
 208         while (*inp != '\0') {
 209                 if (*inp == 0x20)
 210                         *outp++ = '_';
 211                 else if (*inp == '=' || *inp == '?' || *inp == '_' ||
 212                          *inp < 32 || *inp > 127 || g_ascii_isspace(*inp)) {
 213                         *outp++ = '=';
 214                         get_hex_str(outp, *inp);
 215                         outp += 2;
 216                 } else
 217                         *outp++ = *inp;
 218
 219                 inp++;
 220         }
 221
 222         *outp = '\0';
 223 }