apps/iso9660/file.c

   1 /*
   2     iso9660 - An iso9660 CDI driver with Rockridge support
   3     Copyright (C) 2008  Janosch Gräf <janosch.graef@gmx.net>
   4
   5     This program is free software: you can redistribute it and/or modify
   6     it under the terms of the GNU Lesser 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 Lesser General Public License for more details.
  14
  15     You should have received a copy of the GNU Lesser General Public License
  16     along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17 */
  18
  19 #include "cdi/fs.h"
  20 #include "cdi/cache.h"
  21
  22 #include "iso9660_cdi.h"
  23
  24 /**
  25  * Reads from file
  26  *  @param stream CDI FS stream
  27  *  @param start Offset in flie
  28  *  @param size How many bytes to read
  29  *  @param buffer Buffer to store data in
  30  *  @return How many bytes read
  31  */
  32 size_t iso9660_fs_file_read(struct cdi_fs_stream *stream,uint64_t start,size_t size,void *buffer) {
  33   struct iso9660_fs_res *res = (struct iso9660_fs_res*)stream->res;
  34   debug("iso9660_fs_file_read(%s,0x%x,0x%x,0x%x,0x%x)\n",res->res.name,start,size,buffer);
  35
  36   if (start>res->data_size) return 0;
  37   if (start+size>res->data_size) size = res->data_size-start;
  38
  39   iso9660_read(res,start,size,buffer);
  40   return size;
  41 }