Dogcows Code - chaz/tar/blob - src/read_ffs.c

   1 /* Read files directly from the fast file system
   2    Copyright (C) 1992 Free Software Foundation
   3
   4    This file is part of GNU Tar.
   5
   6    GNU Tar is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU General Public License as
   8    published by the Free Software Foundation; either version 2, or (at
   9    your option) any later version.
  10
  11    GNU Tar is distributed in the hope that it will be useful, but
  12    WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with GNU Tar; if not, write to the Free Software
  18    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
  19
  20
  21 dev_t lastdev;
  22 ino_t lastino;
  23
  24 struct dinode ino;
  25 struct fs fs;
  26 off_t offset;
  27 int device_fd;
  28
  29 int *sindir, *dindir, *tindir;
  30 int sindirblk, dindirblk, tindirblk;
  31
  32 read_raw_file (fd, buf, len)
  33      int fd;
  34      char *buf;
  35      int len;
  36 {
  37   struct stat st;
  38   off_t ntoread;
  39   int log_blkno, phys_blkno;
  40
  41   fstat (fd, &st);
  42   if (st.st_dev != lastdev)
  43     new_device (st.st_dev);
  44
  45   if (st.st_ino != lastino)
  46     new_inode (st.st_ino);
  47
  48   /* Only read single blocks at a time */
  49   if (len > fs.fs_bsize)
  50     len = fs.fs_bsize;
  51
  52   /* Prune to the length of the file */
  53   if (offset + len > ino.di_size)
  54     len = ino.di_size - offset;
  55
  56   log_blkno = lblkno (&fs, blkno);
  57