path: root/gnu/usr.bin/tar/extract.c

/* Extract files from a tar archive.
   Copyright (C) 1988, 1992, 1993 Free Software Foundation

This file is part of GNU Tar.

GNU Tar is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU Tar is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Tar; see the file COPYING.  If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */

#ifndef lint
static char rcsid[] = "$NetBSD: extract.c,v 1.6 1995/04/23 08:36:41 cgd Exp $";
#endif /* not lint */

/*
 * Extract files from a tar archive.
 *
 * Written 19 Nov 1985 by John Gilmore, ihnp4!hoptoad!gnu.
 */

#include <stdio.h>
#include <errno.h>
#ifndef STDC_HEADERS
extern int errno;
#endif
#include <sys/types.h>
#include <time.h>
time_t time ();

#ifdef BSD42
#include <sys/file.h>
#else
#ifndef V7
#include <fcntl.h>
#endif
#endif

#ifdef NO_OPEN3
/* We need the #define's even though we don't use them. */
#include "open3.h"
#endif

#ifdef EMUL_OPEN3
/* Simulated 3-argument open for systems that don't have it */
#include "open3.h"
#endif

#include "tar.h"
#include "port.h"

#if defined(_POSIX_VERSION)
#include <utime.h>
#else
struct utimbuf
{
  long actime;
  long modtime;
};

#endif

extern FILE *msg_file;

extern union record *head;	/* Points to current tape header */
extern struct stat hstat;	/* Stat struct corresponding */
extern int head_standard;	/* Tape header is in ANSI format */

extern char *save_name;
extern long save_totsize;
extern long save_sizeleft;

int confirm ();
void decode_header ();
void extract_mangle ();
void extract_sparse_file ();
long from_oct ();
void gnu_restore ();
extern void print_header ();
extern void skip_file ();
extern void skip_extended_headers ();
extern void pr_mkdir ();
void saverec ();

extern PTR ck_malloc();
extern PTR ck_realloc();

int make_dirs ();		/* Makes required directories */

static time_t now = 0;		/* Current time */
static we_are_root = 0;		/* True if our effective uid == 0 */
static int notumask = ~0;	/* Masks out bits user doesn't want */

/*
 * "Scratch" space to store the information about a sparse file before
 * writing the info into the header or extended header
 */
/*struct sp_array	*sparsearray;*/

/* number of elts storable in the sparsearray */
/*int	sp_array_size = 10;*/

struct saved_dir_info
{
  char *path;
  int mode;
  int atime;
  int mtime;
  struct saved_dir_info *next;
};

struct saved_dir_info *saved_dir_info_head;

/*
 * Set up to extract files.
 */
void
extr_init ()
{
  int ourmask;

  now = time ((time_t *) 0);
  if (geteuid () == 0)
    we_are_root = 1;

  /*
	 * We need to know our umask.  But if f_use_protection is set,
	 * leave our kernel umask at 0, and our "notumask" at ~0.
	 */
  ourmask = umask (0);		/* Read it */
  if (!f_use_protection)
    {
      (void) umask (ourmask);	/* Set it back how it was */
      notumask = ~ourmask;	/* Make umask override permissions */
    }
}


/*
 * Extract a file from the archive.
 */
void
extract_archive ()
{
  register char *data;
  int fd, check, namelen, written, openflag;
  long size;
  struct utimbuf acc_upd_times;
  register int skipcrud;
  register int i;
  /*	int sparse_ind = 0;*/
  union record *exhdr;
  struct saved_dir_info *tmp;
  /*	int end_nulls; */

  saverec (&head);		/* Make sure it sticks around */
  userec (head);		/* And go past it in the archive */
  decode_header (head, &hstat, &head_standard, 1);	/* Snarf fields */

  if (f_confirm && !confirm ("extract", current_file_name))
    {
      if (head->header.isextended)
	skip_extended_headers ();
      skip_file ((long) hstat.st_size);
      saverec ((union record **) 0);
      return;
    }

  /* Print the record from 'head' and 'hstat' */
  if (f_verbose)
    print_header ();

  /*
	 * Check for fully specified pathnames and other atrocities.
	 *
	 * Note, we can't just make a pointer to the new file name,
	 * since saverec() might move the header and adjust "head".
	 * We have to start from "head" every time we want to touch
	 * the header record.
	 */
  skipcrud = 0;
  while (!f_absolute_paths
	 && '/' == current_file_name[skipcrud])
    {
      static int warned_once = 0;

      skipcrud++;		/* Force relative path */
      if (!warned_once++)
	{
	  msg ("Removing leading / from absolute path names in the archive.");
	}
    }

  switch (head->header.linkflag)
    {

    default:
      msg ("Unknown file type '%c' for %s, extracted as normal file",
	   head->header.linkflag, skipcrud + current_file_name);
      /* FALL THRU */

      /*
	  * JK - What we want to do if the file is sparse is loop through
	  * the array of sparse structures in the header and read in
	  * and translate the character strings representing  1) the offset
	  * at which to write and 2) how many bytes to write into numbers,
	  * which we store into the scratch array, "sparsearray".  This
	  * array makes our life easier the same way it did in creating
	  * the tar file that had to deal with a sparse file.
	  *
	  * After we read in the first five (at most) sparse structures,
	  * we check to see if the file has an extended header, i.e.,
	  * if more sparse structures are needed to describe the contents
	  * of the new file.  If so, we read in the extended headers
	  * and continue to store their contents into the sparsearray.
	  */
    case LF_SPARSE:
      sp_array_size = 10;
      sparsearray = (struct sp_array *) ck_malloc (sp_array_size * sizeof (struct sp_array));
      for (i = 0; i < SPARSE_IN_HDR; i++)
	{
	  sparsearray[i].offset =
	    from_oct (1 + 12, head->header.sp[i].offset);
	  sparsearray[i].numbytes =
	    from_oct (1 + 12, head->header.sp[i].numbytes);
	  if (!sparsearray[i].numbytes)
	    break;
	}

      /*		end_nulls = from_oct(1+12, head->header.ending_blanks);*/

      if (head->header.isextended)
	{
	  /* read in the list of extended headers
			    and translate them into the sparsearray
			    as before */

	  /* static */ int ind = SPARSE_IN_HDR;

	  for (;;)
	    {

	      exhdr = findrec ();
	      for (i = 0; i < SPARSE_EXT_HDR; i++)
		{

		  if (i + ind > sp_array_size - 1)
		    {
		      /*
					  * realloc the scratch area
					  * since we've run out of room --
					  */
		      sparsearray = (struct sp_array *)
			ck_realloc (sparsearray,
			    2 * sp_array_size * (sizeof (struct sp_array)));
		      sp_array_size *= 2;
		    }
		  if (!exhdr->ext_hdr.sp[i].numbytes)
		    break;
		  sparsearray[i + ind].offset =
		    from_oct (1 + 12, exhdr->ext_hdr.sp[i].offset);
		  sparsearray[i + ind].numbytes =
		    from_oct (1 + 12, exhdr->ext_hdr.sp[i].numbytes);
		}
	      if (!exhdr->ext_hdr.isextended)
		break;
	      else
		{
		  ind += SPARSE_EXT_HDR;
		  userec (exhdr);
		}
	    }
	  userec (exhdr);
	}

      /* FALL THRU */
    case LF_OLDNORMAL:
    case LF_NORMAL:
    case LF_CONTIG:
      /*
		  * Appears to be a file.
		  * See if it's really a directory.
		  */
      namelen = strlen (skipcrud + current_file_name) - 1;
      if (current_file_name[skipcrud + namelen] == '/')
	goto really_dir;

      /* FIXME, deal with protection issues */
    again_file:
      openflag = (f_keep ?
		  O_BINARY | O_NDELAY | O_WRONLY | O_CREAT | O_EXCL :
		  O_BINARY | O_NDELAY | O_WRONLY | O_CREAT | O_TRUNC)
	| ((head->header.linkflag == LF_SPARSE) ? 0 : O_APPEND);
      /*
			  * JK - The last | is a kludge to solve the problem
			  * the O_APPEND flag  causes with files we are
			  * trying to make sparse:  when a file is opened
			  * with O_APPEND, it writes  to the last place
			  * that something was written, thereby ignoring
			  * any lseeks that we have done.  We add this
			  * extra condition to make it able to lseek when
			  * a file is sparse, i.e., we don't open the new
			  * file with this flag.  (Grump -- this bug caused
			  * me to waste a good deal of time, I might add)
			  */

      if (f_exstdout)
	{
	  fd = 1;
	  goto extract_file;
	}

      if (f_unlink && !f_keep) {
	if (unlink(skipcrud + current_file_name) == -1)
		if (errno != ENOENT)
		   msg_perror ("Could not unlink %s",
                      skipcrud + current_file_name);
      }

#ifdef O_CTG
      /*
		  * Contiguous files (on the Masscomp) have to specify
		  * the size in the open call that creates them.
		  */
      if (head->header.linkflag == LF_CONTIG)
	fd = open ((longname ? longname : head->header.name)
		   + skipcrud,
		   openflag | O_CTG,
		   hstat.st_mode, hstat.st_size);
      else
#endif
	{
#ifdef NO_OPEN3
	  /*
			  * On raw V7 we won't let them specify -k (f_keep), but
			  * we just bull ahead and create the files.
			  */
	  fd = creat ((longname
		       ? longname
		       : head->header.name) + skipcrud,
		      hstat.st_mode);
#else
	  /*
			  * With 3-arg open(), we can do this up right.
			  */
	  fd = open (skipcrud + current_file_name,
		     openflag, hstat.st_mode);
#endif
	}

      if (fd < 0)
	{
	  if (make_dirs (skipcrud + current_file_name))
	    goto again_file;
	  msg_perror ("Could not create file %s",
		      skipcrud + current_file_name);
	  if (head->header.isextended)
	    skip_extended_headers ();
	  skip_file ((long) hstat.st_size);
	  goto quit;
	}

    extract_file:
      if (head->header.linkflag == LF_SPARSE)
	{
	  char *name;
	  int namelen;

	  /*
			  * Kludge alert.  NAME is assigned to header.name
			  * because during the extraction, the space that
			  * contains the header will get scribbled on, and
			  * the name will get munged, so any error messages
			  * that happen to contain the filename will look
			  * REAL interesting unless we do this.
			  */
	  namelen = strlen (skipcrud + current_file_name) + 1;
	  name = (char *) ck_malloc ((sizeof (char)) * namelen);
	  bcopy (skipcrud + current_file_name, name, namelen);
	  size = hstat.st_size;
	  extract_sparse_file (fd, &size, hstat.st_size, name);
	}
      else
	for (size = hstat.st_size;
	     size > 0;
	     size -= written)
	  {

	    /*			long	offset,
				 numbytes;*/

	    if (f_multivol)
	      {
		save_name = current_file_name;
		save_totsize = hstat.st_size;
		save_sizeleft = size;
	      }

	    /*
			  * Locate data, determine max length
			  * writeable, write it, record that
			  * we have used the data, then check
			  * if the write worked.
			  */
	    data = findrec ()->charptr;
	    if (data == NULL)
	      {			/* Check it... */
		msg ("Unexpected EOF on archive file");
		break;
	      }
	    /*
			  * JK - If the file is sparse, use the sparsearray
			  * that we created before to lseek into the new
			  * file the proper amount, and to see how many
			  * bytes we want to write at that position.
			  */
	    /*			if (head->header.linkflag == LF_SPARSE) {
				 off_t pos;

				 pos = lseek(fd, (off_t) sparsearray[sparse_ind].offset, 0);
				 printf("%d at %d\n", (int) pos, sparse_ind);
				 written = sparsearray[sparse_ind++].numbytes;
			 } else*/
	    written = endofrecs ()->charptr - data;
	    if (written > size)
	      written = size;
	    errno = 0;
	    check = write (fd, data, written);
	    /*
			  * The following is in violation of strict
			  * typing, since the arg to userec
			  * should be a struct rec *.  FIXME.
			  */
	    userec ((union record *) (data + written - 1));
	    if (check == written)
	      continue;
	    /*
			  * Error in writing to file.
			  * Print it, skip to next file in archive.
			  */
	    if (check < 0)
	      msg_perror ("couldn't write to file %s",
			  skipcrud + current_file_name);
	    else
	      msg ("could only write %d of %d bytes to file %s",
		   check, written, skipcrud + current_file_name);
	    skip_file ((long) (size - written));
	    break;		/* Still do the close, mod time, chmod, etc */
	  }

      if (f_multivol)
	save_name = 0;

      /* If writing to stdout, don't try to do anything
			    to the filename; it doesn't exist, or we don't
			    want to touch it anyway */
      if (f_exstdout)
	break;

      /*		if (head->header.isextended) {
			 register union record *exhdr;
			 register int i;

			 for (i = 0; i < 21; i++) {
				 long offset;

				 if (!exhdr->ext_hdr.sp[i].numbytes)
					 break;
				 offset = from_oct(1+12,
						 exhdr->ext_hdr.sp[i].offset);
				 written = from_oct(1+12,
						 exhdr->ext_hdr.sp[i].numbytes);
				 lseek(fd, offset, 0);
				 check = write(fd, data, written);
				 if (check == written) continue;

			 }


		 }*/
      check = close (fd);
      if (check < 0)
	{
	  msg_perror ("Error while closing %s",
		      skipcrud + current_file_name);
	}


    set_filestat:

      /*
		  * If we are root, set the owner and group of the extracted
		  * file.  This does what is wanted both on real Unix and on
		  * System V.  If we are running as a user, we extract as that
		  * user; if running as root, we extract as the original owner.
		  */
      if (we_are_root || f_do_chown)
	{
	  if (chown (skipcrud + current_file_name,
		     hstat.st_uid, hstat.st_gid) < 0)
	    {
	      msg_perror ("cannot chown file %s to uid %d gid %d",
			  skipcrud + current_file_name,
			  hstat.st_uid, hstat.st_gid);
	    }
	}

      /*
       * Set the modified time of the file.
       *
       * Note that we set the accessed time to "now", which
       * is really "the time we started extracting files".
       * unless f_gnudump is used, in which case .st_atime is used
       */
      if (!f_modified)
	{
	  /* fixme if f_gnudump should set ctime too, but how? */
	  if (f_gnudump)
	    acc_upd_times.actime = hstat.st_atime;
	  else
	    acc_upd_times.actime = now;	/* Accessed now */
	  acc_upd_times.modtime = hstat.st_mtime;	/* Mod'd */
	  if (utime (skipcrud + current_file_name,
		     &acc_upd_times) < 0)
	    {
	      msg_perror ("couldn't change access and modification times of %s", skipcrud + current_file_name);
	    }
	}
      /* We do the utime before the chmod because some versions of
		   utime are broken and trash the modes of the file.  Since
		   we then change the mode anyway, we don't care. . . */

      /*
		 * If '-k' is not set, open() or creat() could have saved
		 * the permission bits from a previously created file,
		 * ignoring the ones we specified.
		 * Even if -k is set, if the file has abnormal
		 * mode bits, we must chmod since writing or chown() has
		 * probably reset them.
		 *
		 * If -k is set, we know *we* created this file, so the mode
		 * bits were set by our open().   If the file is "normal", we
		 * skip the chmod.  This works because we did umask(0) if -p
		 * is set, so umask will have left the specified mode alone.
		 */
      if ((!f_keep)
	  || (hstat.st_mode & (S_ISUID | S_ISGID | S_ISVTX)))
	{
	  if (chmod (skipcrud + current_file_name,
		     notumask & (int) hstat.st_mode) < 0)
	    {
	      msg_perror ("cannot change mode of file %s to %ld",
			  skipcrud + current_file_name,
			  notumask & (int) hstat.st_mode);
	    }
	}

    quit:
      break;

    case LF_LINK:
    again_link:
      if (f_exstdout)
	break;
      {
	struct stat st1, st2;

        if (f_unlink && !f_keep) {
	  if (unlink(skipcrud + current_file_name) == -1)
		if (errno != ENOENT)
		   msg_perror ("Could not unlink %s",
                      skipcrud + current_file_name);
        }

	check = link (current_link_name, skipcrud + current_file_name);

	if (check == 0)
	  break;
	if (make_dirs (skipcrud + current_file_name))
	  goto again_link;
	if (f_gnudump && errno == EEXIST)
	  break;
	if (stat (current_link_name, &st1) == 0
	    && stat (current_file_name + skipcrud, &st2) == 0
	    && st1.st_dev == st2.st_dev
	    && st1.st_ino == st2.st_ino)
	  break;
	msg_perror ("Could not link %s to %s",
		    skipcrud + current_file_name,
		    current_link_name);
      }
      break;

#ifdef S_ISLNK
    case LF_SYMLINK:
    again_symlink:
      if (f_exstdout)
	break;
      if (f_unlink && !f_keep) {
	  if (unlink(skipcrud + current_file_name) == -1)
		if (errno != ENOENT)
		   msg_perror ("Could not unlink %s",
                      skipcrud + current_file_name);
      }

      check = symlink (current_link_name,
		       skipcrud + current_file_name);
      /* FIXME, don't worry uid, gid, etc... */
      if (check == 0)
	break;
      if (make_dirs (current_file_name + skipcrud))
	goto again_symlink;
      msg_perror ("Could not create symlink to %s",
		  current_link_name);
      break;
#endif

#ifdef S_IFCHR
    case LF_CHR:
      hstat.st_mode |= S_IFCHR;
      goto make_node;
#endif

#ifdef S_IFBLK
    case LF_BLK:
      hstat.st_mode |= S_IFBLK;
#endif
#if defined(S_IFCHR) || defined(S_IFBLK)
    make_node:
      if (f_exstdout)
	break;
      if (f_unlink && !f_keep) {
	  if (unlink(skipcrud + current_file_name) == -1)
		if (errno != ENOENT)
		   msg_perror ("Could not unlink %s",
                      skipcrud + current_file_name);
      }

      check = mknod (current_file_name + skipcrud,
		     (int) hstat.st_mode, (int) hstat.st_rdev);
      if (check != 0)
	{
	  if (make_dirs (skipcrud + current_file_name))
	    goto make_node;
	  msg_perror ("Could not make %s",
		      current_file_name + skipcrud);
	  break;
	};
      goto set_filestat;
#endif

#ifdef S_ISFIFO
      /* If local system doesn't support FIFOs, use default case */
    case LF_FIFO:
    make_fifo:
      if (f_exstdout)
	break;
      if (f_unlink && !f_keep) {
	  if (unlink(skipcrud + current_file_name) == -1)
		if (errno != ENOENT)
		   msg_perror ("Could not unlink %s",
                      skipcrud + current_file_name);
      }

      check = mkfifo (current_file_name + skipcrud,
		      (int) hstat.st_mode);
      if (check != 0)
	{
	  if (make_dirs (current_file_name + skipcrud))
	    goto make_fifo;
	  msg_perror ("Could not make %s",
		      skipcrud + current_file_name);
	  break;
	};
      goto set_filestat;
#endif

    case LF_DIR:
    case LF_DUMPDIR:
      namelen = strlen (current_file_name + skipcrud) - 1;
    really_dir:
      if (f_exstdout)
	break;
      /* Check for trailing /, and zap as many as we find. */
      while (namelen
	     && current_file_name[skipcrud + namelen] == '/')
	current_file_name[skipcrud + namelen--] = '\0';
      if (f_gnudump)
	{			/* Read the entry and delete files
					   that aren't listed in the archive */
	  gnu_restore (skipcrud);

	}
      else if (head->header.linkflag == LF_DUMPDIR)
	skip_file ((long) (hstat.st_size));


    again_dir:
      check = mkdir (skipcrud + current_file_name,
		     (we_are_root ? 0 : 0300) | (int) hstat.st_mode);
      if (check != 0)
	{
	  struct stat st1;

	  if (make_dirs (skipcrud + current_file_name))
	    goto again_dir;
	  /* If we're trying to create '.', let it be. */
	  if (current_file_name[skipcrud + namelen] == '.' &&
	      (namelen == 0 ||
	       current_file_name[skipcrud + namelen - 1] == '/'))
	    goto check_perms;
	  if (errno == EEXIST
	      && stat (skipcrud + current_file_name, &st1) == 0
	      && (S_ISDIR (st1.st_mode)))
	    break;
	  msg_perror ("Could not create directory %s", skipcrud + current_file_name);
	  break;
	}

    check_perms:
      if (!we_are_root && 0300 != (0300 & (int) hstat.st_mode))
	{
	  hstat.st_mode |= 0300;
	  msg ("Added write and execute permission to directory %s",
	       skipcrud + current_file_name);
	}

      /*
       * If we are root, set the owner and group of the extracted
       * file.  This does what is wanted both on real Unix and on
       * System V.  If we are running as a user, we extract as that
       * user; if running as root, we extract as the original owner.
       */
      if (we_are_root || f_do_chown)
	{
	  if (chown (skipcrud + current_file_name,
		     hstat.st_uid, hstat.st_gid) < 0)
	    {
	      msg_perror ("cannot chown file %s to uid %d gid %d",
			  skipcrud + current_file_name,
			  hstat.st_uid, hstat.st_gid);
	    }
	}

      if (!f_modified)
	{
	  tmp = ((struct saved_dir_info *) 
		 ck_malloc (sizeof (struct saved_dir_info)));
	  tmp->path = (char *) ck_malloc (strlen (skipcrud 
						  + current_file_name) + 1);
	  strcpy (tmp->path, skipcrud + current_file_name);
	  tmp->mode = hstat.st_mode;
	  tmp->atime = hstat.st_atime;
	  tmp->mtime = hstat.st_mtime;
	  tmp->next = saved_dir_info_head;
	  saved_dir_info_head = tmp;
	}
      else
	{
	  /* This functions exactly as the code for set_filestat above. */
	  if ((!f_keep)
	      || (hstat.st_mode & (S_ISUID | S_ISGID | S_ISVTX)))
	    {
	      if (chmod (skipcrud + current_file_name,
			 notumask & (int) hstat.st_mode) < 0)
		{
		  msg_perror ("cannot change mode of file %s to %ld",
			      skipcrud + current_file_name,
			      notumask & (int) hstat.st_mode);
		}
	    }
	}
      break;

    case LF_VOLHDR:
      if (!f_exstdout && f_verbose)
	  printf ("Reading %s\n", current_file_name);
      break;

    case LF_NAMES:
      if (!f_exstdout)
	  extract_mangle (head);
      break;

    case LF_MULTIVOL:
      msg ("Can't extract '%s'--file is continued from another volume\n", current_file_name);
      skip_file ((long) hstat.st_size);
      break;

    case LF_LONGNAME:
    case LF_LONGLINK:
      msg ("Visible long name error\n");
      skip_file ((long) hstat.st_size);
      break;
    }

  /* We don't need to save it any longer. */
  saverec ((union record **) 0);/* Unsave it */
}

/*
 * After a file/link/symlink/dir creation has failed, see if
 * it's because some required directory was not present, and if
 * so, create all required dirs.
 */
int
make_dirs (pathname)
     char *pathname;
{
  char *p;			/* Points into path */
  int madeone = 0;		/* Did we do anything yet? */
  int save_errno = errno;	/* Remember caller's errno */
  int check;

  if (errno != ENOENT)
    return 0;			/* Not our problem */

  for (p = index (pathname, '/'); p != NULL; p = index (p + 1, '/'))
    {
      /* Avoid mkdir of empty string, if leading or double '/' */
      if (p == pathname || p[-1] == '/')
	continue;
      /* Avoid mkdir where last part of path is '.' */
      if (p[-1] == '.' && (p == pathname + 1 || p[-2] == '/'))
	continue;
      *p = 0;			/* Truncate the path there */
      check = mkdir (pathname, 0777);	/* Try to create it as a dir */
      if (check == 0)
	{
	  /* Fix ownership */
	  if (we_are_root)
	    {
	      if (chown (pathname, hstat.st_uid,
			 hstat.st_gid) < 0)
		{
		  msg_perror ("cannot change owner of %s to uid %d gid %d", pathname, hstat.st_uid, hstat.st_gid);
		}
	    }
	  pr_mkdir (pathname, p - pathname, notumask & 0777);
	  madeone++;		/* Remember if we made one */
	  *p = '/';
	  continue;
	}
      *p = '/';
      if (errno == EEXIST)	/* Directory already exists */
	continue;
      /*
		 * Some other error in the mkdir.  We return to the caller.
		 */
      break;
    }

  errno = save_errno;		/* Restore caller's errno */
  return madeone;		/* Tell them to retry if we made one */
}

void
extract_sparse_file (fd, sizeleft, totalsize, name)
     int fd;
     long *sizeleft, totalsize;
     char *name;
{
  /*	register char	*data;*/
  union record *datarec;
  int sparse_ind = 0;
  int written, count;

  /* assuming sizeleft is initially totalsize */


  while (*sizeleft > 0)
    {
      datarec = findrec ();
      if (datarec == NULL)
	{
	  msg ("Unexpected EOF on archive file");
	  return;
	}
      lseek (fd, sparsearray[sparse_ind].offset, 0);
      written = sparsearray[sparse_ind++].numbytes;
      while (written > RECORDSIZE)
	{
	  count = write (fd, datarec->charptr, RECORDSIZE);
	  if (count < 0)
	    msg_perror ("couldn't write to file %s", name);
	  written -= count;
	  *sizeleft -= count;
	  userec (datarec);
	  datarec = findrec ();
	}

      count = write (fd, datarec->charptr, written);

      if (count < 0)
	{
	  msg_perror ("couldn't write to file %s", name);
	}
      else if (count != written)
	{
	  msg ("could only write %d of %d bytes to file %s", count, 
	       totalsize, name);
	  skip_file ((long) (*sizeleft));
	}

      written -= count;
      *sizeleft -= count;
      userec (datarec);
    }
  free (sparsearray);
  /*	if (end_nulls) {
		register int i;

		printf("%d\n", (int) end_nulls);
		for (i = 0; i < end_nulls; i++)
			write(fd, "\000", 1);
	}*/
  userec (datarec);
}

/* Set back the utime and mode for all the extracted directories. */
void 
restore_saved_dir_info ()
{
  struct utimbuf acc_upd_times;

  while (saved_dir_info_head != NULL)
    {
      /* fixme if f_gnudump should set ctime too, but how? */
      if (f_gnudump)
	acc_upd_times.actime = saved_dir_info_head->atime;
      else
	acc_upd_times.actime = now;	/* Accessed now */
      acc_upd_times.modtime = saved_dir_info_head->mtime;	/* Mod'd */
      if (utime (saved_dir_info_head->path, &acc_upd_times) < 0)
	{
	  msg_perror ("couldn't change access and modification times of %s",
		      saved_dir_info_head->path);
	}
      if ((!f_keep) || (saved_dir_info_head->mode & (S_ISUID | S_ISGID | S_ISVTX)))
	{
	  if (chmod (saved_dir_info_head->path,
		     notumask & saved_dir_info_head->mode) < 0)
	    {
	      msg_perror ("cannot change mode of file %s to %ld",
			  saved_dir_info_head->path,
			  notumask & saved_dir_info_head->mode);
	    }
	}
      saved_dir_info_head = saved_dir_info_head->next;
    }
}