tools/torrent/mktorrent_crc/output.c

   1 /*
   2 This file is part of mktorrent
   3 Copyright (C) 2007, 2009 Emil Renner Berthing
   4
   5 mktorrent 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 mktorrent 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 #ifndef ALLINONE
  20 #include <sys/types.h>    /* off_t */
  21 #include <stdio.h>        /* printf() etc. */
  22 #include <string.h>       /* strlen() etc. */
  23 #include <time.h>         /* time() */
  24 #ifdef USE_OPENSSL
  25 #include <openssl/sha.h>  /* SHA_DIGEST_LENGTH */
  26 #else
  27 #include <inttypes.h>
  28 #include "sha1.h"
  29 #endif
  30
  31 #include "mktorrent.h"
  32
  33 #define EXPORT
  34 #endif /* ALLINONE */
  35
  36 /*
  37  * write announce list
  38  */
  39 static void write_announce_list(FILE *f, llist_t *list)
  40 {
  41         /* the announce list is a list of lists of urls */
  42         fprintf(f, "13:announce-listl");
  43         /* go through them all.. */
  44         for (; list; list = list->next) {
  45                 slist_t *l;
  46
  47                 /* .. and print the lists */
  48                 fprintf(f, "l");
  49                 for (l = list->l; l; l = l->next)
  50                         fprintf(f, "%lu:%s",
  51                                         (unsigned long)strlen(l->s), l->s);
  52                 fprintf(f, "e");
  53         }
  54         fprintf(f, "e");
  55 }
  56
  57 /*
  58  * write file list
  59  */
  60 static void write_file_list(FILE *f, flist_t *list)
  61 {
  62         char *a, *b;
  63
  64         fprintf(f, "5:filesl");
  65
  66         /* go through all the files */
  67         for (; list; list = list->next) {
  68                 /* the file list contains a dictionary for every file
  69                    with entries for the length and path
  70                    write the length first */
  71                 fprintf(f, "d4:hash8:%s6:lengthi%" PRIoff "e4:pathl",list->hash, list->size);
  72                 /* the file path is written as a list of subdirectories
  73                    and the last entry is the filename
  74                    sorry this code is even uglier than the rest */
  75                 a = list->path;
  76                 /* while there are subdirectories before the filename.. */
  77                 while ((b = strchr(a, DIRSEP_CHAR)) != NULL) {
  78                         /* set the next DIRSEP_CHAR to '\0' so fprintf
  79                            will only write the first subdirectory name */
  80                         *b = '\0';
  81                         /* print it bencoded */
  82                         fprintf(f, "%lu:%s", (unsigned long)strlen(a), a);
  83                         /* undo our alteration to the string */
  84                         *b = DIRSEP_CHAR;
  85                         /* and move a to the beginning of the next
  86                            subdir or filename */
  87                         a = b + 1;
  88                 }
  89                 /* now print the filename bencoded and end the
  90                    path name list and file dictionary */
  91                 fprintf(f, "%lu:%see", (unsigned long)strlen(a), a);
  92         }
  93
  94         /* whew, now end the file list */
  95         fprintf(f, "e");
  96 }
  97
  98 /*
  99  * write web seed list
 100  */
 101 static void write_web_seed_list(FILE *f, slist_t *list)
 102 {
 103         /* print the entry and start the list */
 104         fprintf(f, "8:url-listl");
 105         /* go through the list and write each URL */
 106         for (; list; list = list->next)
 107                 fprintf(f, "%lu:%s", (unsigned long)strlen(list->s), list->s);
 108         /* end the list */
 109         fprintf(f, "e");
 110 }
 111
 112 /*
 113  * write metainfo to the file stream using all the information
 114  * we've gathered so far and the hash string calculated
 115  */
 116 EXPORT void write_metainfo(FILE *f, metafile_t *m, unsigned char *hash_string)
 117 {
 118         /* let the user know we've started writing the metainfo file */
 119         printf("Writing metainfo file... ");
 120         fflush(stdout);
 121
 122         /* every metainfo file is one big dictonary
 123            and the first entry is the announce URL */
 124         fprintf(f, "d8:announce%lu:%s",
 125                 (unsigned long)strlen(m->announce_list->l->s),
 126                 m->announce_list->l->s);
 127         /* write the announce-list entry if we have
 128            more than one announce URL */
 129         if (m->announce_list->next || m->announce_list->l->next)
 130                 write_announce_list(f, m->announce_list);
 131         /* add the comment if one is specified */
 132         if (m->comment != NULL)
 133                 fprintf(f, "7:comment%lu:%s",
 134                                 (unsigned long)strlen(m->comment),
 135                                 m->comment);
 136         /* I made this! */
 137         fprintf(f, "10:created by17:mktorrent_crc 0.2");
 138         /* add the creation date */
 139         if (!m->no_creation_date)
 140                 fprintf(f, "13:creation datei%lde",
 141                         (long)time(NULL));
 142
 143         /* now here comes the info section
 144            it is yet another dictionary */
 145         fprintf(f, "4:infod");
 146         /* first entry is either 'length', which specifies the length of a
 147            single file torrent, or a list of files and their respective sizes */
 148         if (!m->target_is_directory)
 149                 fprintf(f, "6:lengthi%" PRIoff "e", m->file_list->size);
 150         else
 151                 write_file_list(f, m->file_list);
 152
 153         /* the info section also contains the name of the torrent,
 154            the piece length and the hash string */
 155         fprintf(f, "4:name%lu:%s12:piece lengthi%ue6:pieces%u:",
 156                 (unsigned long)strlen(m->torrent_name), m->torrent_name,
 157                 m->piece_length, m->pieces * SHA_DIGEST_LENGTH);
 158         fwrite(hash_string, 1, m->pieces * SHA_DIGEST_LENGTH, f);
 159
 160         /* set the private flag */
 161         if (m->private)
 162                 fprintf(f, "7:privatei1e");
 163
 164         /* end the info section */
 165         fprintf(f, "e");
 166
 167         /* add url-list if one is specified */
 168         if (m->web_seed_list != NULL) {
 169                 if (m->web_seed_list->next == NULL)
 170                         fprintf(f, "8:url-list%lu:%s",
 171                                         (unsigned long)strlen(m->web_seed_list->s),
 172                                         m->web_seed_list->s);
 173                 else
 174                         write_web_seed_list(f, m->web_seed_list);
 175         }
 176
 177         /* end the root dictionary */
 178         fprintf(f, "e");
 179
 180         /* let the user know we're done already */
 181         printf("done.\n");
 182         fflush(stdout);
 183 }