src/common/quoted-printable.c

   1 /*
   2  * Sylpheed -- a GTK+ based, lightweight, and fast e-mail client
   3  * Copyright (C) 1999-2012 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 3 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, see <http://www.gnu.org/licenses/>.
  17  *
  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] &&
  94                             get_hex_value((guchar *)outp, inp[1], inp[2])
  95                             == TRUE) {
  96                                 inp += 3;
  97                         } else if (inp[1] == '\0' || g_ascii_isspace(inp[1])) {
  98                                 /* soft line break */
  99                                 break;
 100                         } else {
 101                                 /* broken QP string */
 102                                 *outp = *inp++;
 103                         }
 104                 } else {
 105                         *outp = *inp++;
 106                 }
 107                 outp++;
 108         }
 109
 110         *outp = '\0';
 111
 112         return outp - str;
 113 }
 114
 115 gint qp_decode_const(gchar *out, gint avail, const gchar *str)
 116 {
 117         const gchar *inp = str;
 118         gchar *outp = out;
 119
 120         while (*inp != '\0' && avail > 0) {
 121                 if (*inp == '=') {
 122                         if (inp[1] && inp[2] &&
 123                             get_hex_value((guchar *)outp, inp[1], inp[2])
 124                             == TRUE) {
 125                                 inp += 3;
 126                         } else if (inp[1] == '\0' || g_ascii_isspace(inp[1])) {
 127                                 /* soft line break */
 128                                 break;
 129                         } else {
 130                                 /* broken QP string */
 131                                 *outp = *inp++;
 132                         }
 133                 } else {
 134                         *outp = *inp++;
 135                 }
 136                 outp++;
 137                 avail--;
 138         }
 139
 140         *outp = '\0';
 141
 142         return outp - out;
 143 }
 144
 145 gint qp_decode_q_encoding(guchar *out, const gchar *in, gint inlen)
 146 {
 147         const gchar *inp = in;
 148         guchar *outp = out;
 149
 150         if (inlen < 0)
 151                 inlen = G_MAXINT;
 152
 153         while (inp - in < inlen && *inp != '\0') {
 154                 if (*inp == '=' && inp + 3 - in <= inlen) {
 155                         if (get_hex_value(outp, inp[1], inp[2]) == TRUE) {
 156                                 inp += 3;
 157                         } else {
 158                                 *outp = *inp++;
 159                         }
 160                 } else if (*inp == '_') {
 161                         *outp = ' ';
 162                         inp++;
 163                 } else {
 164                         *outp = *inp++;
 165                 }
 166                 outp++;
 167         }
 168
 169         *outp = '\0';
 170
 171         return outp - out;
 172 }
 173
 174 gint qp_get_q_encoding_len(const guchar *str)
 175 {
 176         const guchar *inp = str;
 177         gint len = 0;
 178
 179         while (*inp != '\0') {
 180                 if (*inp == 0x20)
 181                         len++;
 182                 else if (*inp == '=' || *inp == '?' || *inp == '_' ||
 183                          *inp < 32 || *inp > 127 || g_ascii_isspace(*inp))
 184                         len += 3;
 185                 else
 186                         len++;
 187
 188                 inp++;
 189         }
 190
 191         return len;
 192 }
 193
 194 void qp_q_encode(gchar *out, const guchar *in)
 195 {
 196         const guchar *inp = in;
 197         gchar *outp = out;
 198
 199         while (*inp != '\0') {
 200                 if (*inp == 0x20)
 201                         *outp++ = '_';
 202                 else if (*inp == '=' || *inp == '?' || *inp == '_' ||
 203                          *inp < 32 || *inp > 127 || g_ascii_isspace(*inp)) {
 204                         *outp++ = '=';
 205                         get_hex_str(outp, *inp);
 206                         outp += 2;
 207                 } else
 208                         *outp++ = *inp;
 209
 210                 inp++;
 211         }
 212
 213         *outp = '\0';
 214 }