src/common/quoted-printable.c

   1 /*
   2  * Claws Mail -- 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 "config.h"
  21
  22 #include <glib.h>
  23 #include <ctype.h>
  24
  25 #include "utils.h"
  26
  27 #define MAX_LINELEN     76
  28
  29 #define IS_LBREAK(p) \
  30         (*(p) == '\0' || *(p) == '\n' || (*(p) == '\r' && *((p) + 1) == '\n'))
  31
  32 #define SOFT_LBREAK_IF_REQUIRED(n)                                      \
  33         if (len + (n) > MAX_LINELEN ||                                  \
  34             (len + (n) == MAX_LINELEN && (!IS_LBREAK(inp + 1)))) {      \
  35                 *outp++ = '=';                                          \
  36                 *outp++ = '\n';                                         \
  37                 len = 0;                                                \
  38         }
  39
  40 void qp_encode_line(gchar *out, const guchar *in)
  41 {
  42         const guchar *inp = in;
  43         gchar *outp = out;
  44         guchar ch;
  45         gint len = 0;
  46
  47         while (*inp != '\0') {
  48                 ch = *inp;
  49
  50                 if (IS_LBREAK(inp)) {
  51                         *outp++ = '\n';
  52                         len = 0;
  53                         if (*inp == '\r')
  54                                 inp++;
  55                         inp++;
  56                 } else if (ch == '\t' || ch == ' ') {
  57                         if (IS_LBREAK(inp + 1)) {
  58                                 SOFT_LBREAK_IF_REQUIRED(3);
  59                                 *outp++ = '=';
  60                                 get_hex_str(outp, ch);
  61                                 outp += 2;
  62                                 len += 3;
  63                                 inp++;
  64                         } else {
  65                                 SOFT_LBREAK_IF_REQUIRED(1);
  66                                 *outp++ = *inp++;
  67                                 len++;
  68                         }
  69                 } else if ((ch >= 33 && ch <= 60) || (ch >= 62 && ch <= 126)) {
  70                         SOFT_LBREAK_IF_REQUIRED(1);
  71                         *outp++ = *inp++;
  72                         len++;
  73                 } else {
  74                         SOFT_LBREAK_IF_REQUIRED(3);
  75                         *outp++ = '=';
  76                         get_hex_str(outp, ch);
  77                         outp += 2;
  78                         len += 3;
  79                         inp++;
  80                 }
  81         }
  82
  83         if (len > 0)
  84                 *outp++ = '\n';
  85
  86         *outp = '\0';
  87 }
  88
  89 gint qp_decode_line(gchar *str)
  90 {
  91         gchar *inp = str, *outp = str;
  92
  93         while (*inp != '\0') {
  94                 if (*inp == '=') {
  95                         if (inp[1] && inp[2] &&
  96                             get_hex_value((guchar *)outp, inp[1], inp[2])
  97                             == TRUE) {
  98                                 inp += 3;
  99                         } else if (inp[1] == '\0' || g_ascii_isspace(inp[1])) {
 100                                 /* soft line break */
 101                                 break;
 102                         } else {
 103                                 /* broken QP string */
 104                                 *outp = *inp++;
 105                         }
 106                 } else {
 107                         *outp = *inp++;
 108                 }
 109                 outp++;
 110         }
 111
 112         *outp = '\0';
 113
 114         return outp - str;
 115 }
 116
 117 gint qp_decode_const(gchar *out, gint avail, const gchar *str)
 118 {
 119         const gchar *inp = str;
 120         gchar *outp = out;
 121
 122         while (*inp != '\0' && avail > 0) {
 123                 if (*inp == '=') {
 124                         if (inp[1] && inp[2] &&
 125                             get_hex_value((guchar *)outp, inp[1], inp[2])
 126                             == TRUE) {
 127                                 inp += 3;
 128                         } else if (inp[1] == '\0' || g_ascii_isspace(inp[1])) {
 129                                 /* soft line break */
 130                                 break;
 131                         } else {
 132                                 /* broken QP string */
 133                                 *outp = *inp++;
 134                         }
 135                 } else {
 136                         *outp = *inp++;
 137                 }
 138                 outp++;
 139                 avail--;
 140         }
 141
 142         *outp = '\0';
 143
 144         return outp - out;
 145 }
 146
 147 gint qp_decode_q_encoding(guchar *out, const gchar *in, gint inlen)
 148 {
 149         const gchar *inp = in;
 150         guchar *outp = out;
 151
 152         if (inlen < 0)
 153                 inlen = G_MAXINT;
 154
 155         while (inp - in < inlen && *inp != '\0') {
 156                 if (*inp == '=' && inp + 3 - in <= inlen) {
 157                         if (get_hex_value(outp, inp[1], inp[2]) == TRUE) {
 158                                 inp += 3;
 159                         } else {
 160                                 *outp = *inp++;
 161                         }
 162                 } else if (*inp == '_') {
 163                         *outp = ' ';
 164                         inp++;
 165                 } else {
 166                         *outp = *inp++;
 167                 }
 168                 outp++;
 169         }
 170
 171         *outp = '\0';
 172
 173         return outp - out;
 174 }
 175
 176 gint qp_get_q_encoding_len(const guchar *str)
 177 {
 178         const guchar *inp = str;
 179         gint len = 0;
 180
 181         while (*inp != '\0') {
 182                 if (*inp == 0x20)
 183                         len++;
 184                 else if (*inp == '=' || *inp == '?' || *inp == '_' ||
 185                          *inp < 32 || *inp > 127 || g_ascii_isspace(*inp))
 186                         len += 3;
 187                 else
 188                         len++;
 189
 190                 inp++;
 191         }
 192
 193         return len;
 194 }
 195
 196 void qp_q_encode(gchar *out, const guchar *in)
 197 {
 198         const guchar *inp = in;
 199         gchar *outp = out;
 200
 201         while (*inp != '\0') {
 202                 if (*inp == 0x20)
 203                         *outp++ = '_';
 204                 else if (*inp == '=' || *inp == '?' || *inp == '_' ||
 205                          *inp < 32 || *inp > 127 || g_ascii_isspace(*inp)) {
 206                         *outp++ = '=';
 207                         get_hex_str(outp, *inp);
 208                         outp += 2;
 209                 } else
 210                         *outp++ = *inp;
 211
 212                 inp++;
 213         }
 214
 215         *outp = '\0';
 216 }