tar: --atime-preserve fixes for races etc.

[chaz/tar] / src / extract.c

diff --git a/src/extract.c b/src/extract.c
index 0ed41532592c683bec9a905e2ad749bf6c080957..2296066591624d6fb7bd8b8089632402cef3b225 100644 (file)
--- a/src/extract.c
+++ b/src/extract.c
@@ -1,13 +1,13 @@
 /* Extract files from a tar archive.
 
    Copyright (C) 1988, 1992, 1993, 1994, 1996, 1997, 1998, 1999, 2000,
 /* Extract files from a tar archive.
 
    Copyright (C) 1988, 1992, 1993, 1994, 1996, 1997, 1998, 1999, 2000,

-   2001, 2003, 2004 Free Software Foundation, Inc.
+   2001, 2003, 2004, 2005, 2006, 2007, 2010 Free Software Foundation, Inc.

 
    Written by John Gilmore, on 1985-11-19.
 
    This program is free software; you can redistribute it and/or modify it
    under the terms of the GNU General Public License as published by the
 
    Written by John Gilmore, on 1985-11-19.
 
    This program 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
+   Free Software Foundation; either version 3, or (at your option) any later

    version.
 
    This program is distributed in the hope that it will be useful, but
    version.
 
    This program is distributed in the hope that it will be useful, but


@@ -17,25 +17,16 @@
 
    You should have received a copy of the GNU General Public License along
    with this program; if not, write to the Free Software Foundation, Inc.,
 
    You should have received a copy of the GNU General Public License along
    with this program; if not, write to the Free Software Foundation, Inc.,

-   59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
+   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */

 
 

-#include "system.h"
+#include <system.h>

 #include <quotearg.h>
 #include <errno.h>
 #include <quotearg.h>
 #include <errno.h>

-
-#if HAVE_UTIME_H
-# include <utime.h>
-#else
-struct utimbuf
-  {
-    long actime;
-    long modtime;
-  };
-#endif
+#include <priv-set.h>

 
 #include "common.h"
 
 
 #include "common.h"
 

-bool we_are_root;              /* true if our effective uid == 0 */
+static bool we_are_root;       /* true if our effective uid == 0 */

 static mode_t newdir_umask;    /* umask when creating new directories */
 static mode_t current_umask;   /* current umask (which is set to 0 if -p) */
 
 static mode_t newdir_umask;    /* umask when creating new directories */
 static mode_t current_umask;   /* current umask (which is set to 0 if -p) */
 


@@ -45,7 +36,8 @@ enum permstatus
   /* This file may have existed already; its permissions are unknown.  */
   UNKNOWN_PERMSTATUS,
 
   /* This file may have existed already; its permissions are unknown.  */
   UNKNOWN_PERMSTATUS,
 

-  /* This file was created using the permissions from the archive.  */
+  /* This file was created using the permissions from the archive,
+     except with S_IRWXG | S_IRWXO masked out if 0 < same_owner_option.  */

   ARCHIVED_PERMSTATUS,
 
   /* This is an intermediate directory; the archive did not specify
   ARCHIVED_PERMSTATUS,
 
   /* This is an intermediate directory; the archive did not specify


@@ -56,8 +48,8 @@ enum permstatus
 /* List of directories whose statuses we need to extract after we've
    finished extracting their subsidiary files.  If you consider each
    contiguous subsequence of elements of the form [D]?[^D]*, where [D]
 /* List of directories whose statuses we need to extract after we've
    finished extracting their subsidiary files.  If you consider each
    contiguous subsequence of elements of the form [D]?[^D]*, where [D]

-   represents an element where AFTER_SYMLINKS is nonzero and [^D]
-   represents an element where AFTER_SYMLINKS is zero, then the head
+   represents an element where AFTER_LINKS is nonzero and [^D]
+   represents an element where AFTER_LINKS is zero, then the head

    of the subsequence has the longest name, and each non-head element
    in the prefix is an ancestor (in the directory hierarchy) of the
    preceding element.  */
    of the subsequence has the longest name, and each non-head element
    in the prefix is an ancestor (in the directory hierarchy) of the
    preceding element.  */


@@ -65,32 +57,47 @@ enum permstatus
 struct delayed_set_stat
   {
     struct delayed_set_stat *next;
 struct delayed_set_stat
   {
     struct delayed_set_stat *next;

-    struct stat stat_info;
+    dev_t dev;
+    ino_t ino;
+    mode_t mode;
+    uid_t uid;
+    gid_t gid;
+    struct timespec atime;
+    struct timespec mtime;

     size_t file_name_len;
     mode_t invert_permissions;
     enum permstatus permstatus;
     size_t file_name_len;
     mode_t invert_permissions;
     enum permstatus permstatus;

-    bool after_symlinks;
+    bool after_links;
+    int change_dir;

     char file_name[1];
   };
 
 static struct delayed_set_stat *delayed_set_stat_head;
 
     char file_name[1];
   };
 
 static struct delayed_set_stat *delayed_set_stat_head;
 

-/* List of symbolic links whose creation we have delayed.  */
-struct delayed_symlink
+/* List of links whose creation we have delayed.  */
+struct delayed_link

   {
   {

-    /* The next delayed symbolic link in the list.  */
-    struct delayed_symlink *next;
+    /* The next delayed link in the list.  */
+    struct delayed_link *next;

 
 

-    /* The device, inode number and last-modified time of the placeholder.  */
+    /* The device, inode number and ctime of the placeholder.  Use
+       ctime, not mtime, to make false matches less likely if some
+       other process removes the placeholder.  */

     dev_t dev;
     ino_t ino;
     dev_t dev;
     ino_t ino;

-    time_t mtime;
+    struct timespec ctime;
+
+    /* True if the link is symbolic.  */
+    bool is_symlink;

 
 

-    /* The desired owner and group of the symbolic link.  */
+    /* The desired owner and group of the link, if it is a symlink.  */

     uid_t uid;
     gid_t gid;
 
     uid_t uid;
     gid_t gid;
 

-    /* A list of sources for this symlink.  The sources are all to be
+    /* The directory that the sources and target are relative to.  */
+    int change_dir;
+
+    /* A list of sources for this link.  The sources are all to be

        hard-linked together.  */
     struct string_list *sources;
 
        hard-linked together.  */
     struct string_list *sources;
 


@@ -98,7 +105,7 @@ struct delayed_symlink
     char target[1];
   };
 
     char target[1];
   };
 

-static struct delayed_symlink *delayed_symlink_head;
+static struct delayed_link *delayed_link_head;

 
 struct string_list
   {
 
 struct string_list
   {


@@ -113,7 +120,6 @@ extr_init (void)
   we_are_root = geteuid () == 0;
   same_permissions_option += we_are_root;
   same_owner_option += we_are_root;
   we_are_root = geteuid () == 0;
   same_permissions_option += we_are_root;
   same_owner_option += we_are_root;

-  xalloc_fail_func = extract_finish;

 
   /* Option -p clears the kernel umask, so it does not affect proper
      restoration of file permissions.  New intermediate directories will
 
   /* Option -p clears the kernel umask, so it does not affect proper
      restoration of file permissions.  New intermediate directories will


@@ -129,8 +135,40 @@ extr_init (void)
     }
 }
 
     }
 }
 

+/* Use fchmod if possible, chmod otherwise.  */
+static int
+fdchmod (char const *file, int fd, mode_t mode)
+{
+#if HAVE_FCHMOD
+  if (0 <= fd)
+    return fchmod (fd, mode);
+#endif
+  return chmod (file, mode);
+}
+
+/* Use fchown if possible, chown otherwise.  */
+static int
+fdchown (char const *file, int fd, uid_t uid, gid_t gid)
+{
+#if HAVE_FCHOWN
+  if (0 <= fd)
+    return fchown (fd, uid, gid);
+#endif
+  return chown (file, uid, gid);
+}
+
+/* Use fstat if possible, stat otherwise.  */
+static int
+fdstat (char const *file, int fd, struct stat *st)
+{
+  if (0 <= fd)
+    return fstat (fd, st);
+  return stat (file, st);
+}
+

 /* If restoring permissions, restore the mode for FILE_NAME from
 /* If restoring permissions, restore the mode for FILE_NAME from

-   information given in *STAT_INFO (where *CUR_INFO gives
+   information given in *STAT_INFO (where FD is a file descriptor
+   for the file if FD is nonnegative, and where *CUR_INFO gives

    the current status if CUR_INFO is nonzero); otherwise invert the
    INVERT_PERMISSIONS bits from the file's current permissions.
    PERMSTATUS specifies the status of the file's permissions.
    the current status if CUR_INFO is nonzero); otherwise invert the
    INVERT_PERMISSIONS bits from the file's current permissions.
    PERMSTATUS specifies the status of the file's permissions.


@@ -138,23 +176,27 @@ extr_init (void)
 static void
 set_mode (char const *file_name,
          struct stat const *stat_info,
 static void
 set_mode (char const *file_name,
          struct stat const *stat_info,

-         struct stat const *cur_info,
+         int fd, struct stat const *cur_info,

          mode_t invert_permissions, enum permstatus permstatus,
          char typeflag)
 {
   mode_t mode;
          mode_t invert_permissions, enum permstatus permstatus,
          char typeflag)
 {
   mode_t mode;

+  int chmod_errno;

 
   if (0 < same_permissions_option
       && permstatus != INTERDIR_PERMSTATUS)
     {
       mode = stat_info->st_mode;
 
 
   if (0 < same_permissions_option
       && permstatus != INTERDIR_PERMSTATUS)
     {
       mode = stat_info->st_mode;
 

-      /* If we created the file and it has a usual mode, then its mode
-        is normally set correctly already.  But on many hosts, some
+      /* If we created the file and it has a mode that we set already
+        with O_CREAT, then its mode is often set correctly already.
+        But if we are changing ownership, the mode's group and and
+        other permission bits were omitted originally, so it's less
+        likely that the mode is OK now.  Also, on many hosts, some

         directories inherit the setgid bits from their parents, so we
         we must set directories' modes explicitly.  */
         directories inherit the setgid bits from their parents, so we
         we must set directories' modes explicitly.  */

-      if (permstatus == ARCHIVED_PERMSTATUS
-         && ! (mode & ~ MODE_RWX)
+      if ((permstatus == ARCHIVED_PERMSTATUS
+          && ! (mode & ~ (0 < same_owner_option ? S_IRWXU : MODE_RWX)))

          && typeflag != DIRTYPE
          && typeflag != GNUTYPE_DUMPDIR)
        return;
          && typeflag != DIRTYPE
          && typeflag != GNUTYPE_DUMPDIR)
        return;


@@ -172,7 +214,7 @@ set_mode (char const *file_name,
       struct stat st;
       if (! cur_info)
        {
       struct stat st;
       if (! cur_info)
        {

-         if (stat (file_name, &st) != 0)
+         if (fdstat (file_name, fd, &st) != 0)

            {
              stat_error (file_name);
              return;
            {
              stat_error (file_name);
              return;


@@ -182,27 +224,61 @@ set_mode (char const *file_name,
       mode = cur_info->st_mode ^ invert_permissions;
     }
 
       mode = cur_info->st_mode ^ invert_permissions;
     }
 

-  if (chmod (file_name, mode) != 0)
-    chmod_error_details (file_name, mode);
+  chmod_errno = fdchmod (file_name, fd, mode) == 0 ? 0 : errno;
+  if (chmod_errno == EPERM && (mode & S_ISUID) != 0)
+    {
+      /* On Solaris, chmod may fail if we don't have PRIV_ALL, because
+        setuid-root files would otherwise be a backdoor.  See
+        http://opensolaris.org/jive/thread.jspa?threadID=95826
+        (2009-09-03).  */
+      if (priv_set_restore_linkdir () == 0)
+       {
+         chmod_errno = fdchmod (file_name, fd, mode) == 0 ? 0 : errno;
+         priv_set_remove_linkdir ();
+       }
+    }
+  if (chmod_errno)
+    {
+      errno = chmod_errno;
+      chmod_error_details (file_name, mode);
+    }

 }
 
 /* Check time after successfully setting FILE_NAME's time stamp to T.  */
 static void
 }
 
 /* Check time after successfully setting FILE_NAME's time stamp to T.  */
 static void

-check_time (char const *file_name, time_t t)
+check_time (char const *file_name, struct timespec t)

 {
 {

-  time_t now;
-  if (t <= 0)
-    WARN ((0, 0, _("%s: implausibly old time stamp %s"),
-          file_name, tartime (t)));
-  else if (start_time < t && (now = time (0)) < t)
-    WARN ((0, 0, _("%s: time stamp %s is %lu s in the future"),
-          file_name, tartime (t), (unsigned long) (t - now)));
+  if (t.tv_sec <= 0)
+    WARNOPT (WARN_TIMESTAMP,
+            (0, 0, _("%s: implausibly old time stamp %s"),
+             file_name, tartime (t, true)));
+  else if (timespec_cmp (volume_start_time, t) < 0)
+    {
+      struct timespec now;
+      gettime (&now);
+      if (timespec_cmp (now, t) < 0)
+       {
+         char buf[TIMESPEC_STRSIZE_BOUND];
+         struct timespec diff;
+         diff.tv_sec = t.tv_sec - now.tv_sec;
+         diff.tv_nsec = t.tv_nsec - now.tv_nsec;
+         if (diff.tv_nsec < 0)
+           {
+             diff.tv_nsec += BILLION;
+             diff.tv_sec--;
+           }
+         WARNOPT (WARN_TIMESTAMP,
+                  (0, 0, _("%s: time stamp %s is %s s in the future"),
+                   file_name, tartime (t, true), code_timespec (diff, buf)));
+       }
+    }

 }
 
 /* Restore stat attributes (owner, group, mode and times) for
 }
 
 /* Restore stat attributes (owner, group, mode and times) for

-   FILE_NAME, using information given in *STAT_INFO.
+   FILE_NAME, using information given in *ST.
+   If FD is nonnegative, it is a file descriptor for the file.

    If CUR_INFO is nonzero, *CUR_INFO is the
    If CUR_INFO is nonzero, *CUR_INFO is the

-   file's currernt status.
+   file's current status.

    If not restoring permissions, invert the
    INVERT_PERMISSIONS bits from the file's current permissions.
    PERMSTATUS specifies the status of the file's permissions.
    If not restoring permissions, invert the
    INVERT_PERMISSIONS bits from the file's current permissions.
    PERMSTATUS specifies the status of the file's permissions.


@@ -215,13 +291,11 @@ check_time (char const *file_name, time_t t)
 
 static void
 set_stat (char const *file_name,
 
 static void
 set_stat (char const *file_name,

-         struct stat const *stat_info,
-         struct stat const *cur_info,
+         struct tar_stat_info const *st,
+         int fd, struct stat const *cur_info,

          mode_t invert_permissions, enum permstatus permstatus,
          char typeflag)
 {
          mode_t invert_permissions, enum permstatus permstatus,
          char typeflag)
 {

-  struct utimbuf utimbuf;
-

   if (typeflag != SYMTYPE)
     {
       /* We do the utime before the chmod because some versions of utime are
   if (typeflag != SYMTYPE)
     {
       /* We do the utime before the chmod because some versions of utime are


@@ -229,34 +303,29 @@ set_stat (char const *file_name,
 
       if (! touch_option && permstatus != INTERDIR_PERMSTATUS)
        {
 
       if (! touch_option && permstatus != INTERDIR_PERMSTATUS)
        {

-         /* We set the accessed time to `now', which is really the time we
-            started extracting files, unless incremental_option is used, in
-            which case .st_atime is used.  */
-
-         /* FIXME: incremental_option should set ctime too, but how?  */
-
+         struct timespec ts[2];

          if (incremental_option)
          if (incremental_option)

-           utimbuf.actime = stat_info->st_atime;
+           ts[0] = st->atime;

          else
          else

-           utimbuf.actime = start_time;
+           ts[0].tv_nsec = UTIME_NOW;
+         ts[1] = st->mtime;

 
 

-         utimbuf.modtime = stat_info->st_mtime;
-
-         if (utime (file_name, &utimbuf) < 0)
+         if (fd_utimensat (fd, AT_FDCWD, file_name, ts, 0) != 0)

            utime_error (file_name);
          else
            {
            utime_error (file_name);
          else
            {

-             check_time (file_name, utimbuf.actime);
-             check_time (file_name, utimbuf.modtime);
+             if (incremental_option)
+               check_time (file_name, ts[0]);
+             check_time (file_name, ts[1]);

            }
        }
 
       /* Some systems allow non-root users to give files away.  Once this
            }
        }
 
       /* Some systems allow non-root users to give files away.  Once this

-        done, it is not possible anymore to change file permissions, so we
-        have to set permissions prior to possibly giving files away.  */
-
-      set_mode (file_name, stat_info, cur_info,
-               invert_permissions, permstatus, typeflag);
+        done, it is not possible anymore to change file permissions.
+        However, setting file permissions now would be incorrect, since
+        they would apply to the wrong user, and there would be a race
+        condition.  So, don't use systems that allow non-root users to
+        give files away.  */

     }
 
   if (0 < same_owner_option && permstatus != INTERDIR_PERMSTATUS)
     }
 
   if (0 < same_owner_option && permstatus != INTERDIR_PERMSTATUS)


@@ -265,52 +334,79 @@ set_stat (char const *file_name,
         the symbolic link itself.  In this case, a mere chown would change
         the attributes of the file the symbolic link is pointing to, and
         should be avoided.  */
         the symbolic link itself.  In this case, a mere chown would change
         the attributes of the file the symbolic link is pointing to, and
         should be avoided.  */

+      int chown_result = 1;

 
       if (typeflag == SYMTYPE)
        {
 #if HAVE_LCHOWN
 
       if (typeflag == SYMTYPE)
        {
 #if HAVE_LCHOWN

-         if (lchown (file_name, stat_info->st_uid, stat_info->st_gid) < 0)
-           chown_error_details (file_name,
-                                stat_info->st_uid, stat_info->st_gid);
+         chown_result = lchown (file_name, st->stat.st_uid, st->stat.st_gid);

 #endif
        }
       else
        {
 #endif
        }
       else
        {

-         if (chown (file_name, stat_info->st_uid, stat_info->st_gid) < 0)
-           chown_error_details (file_name,
-                                stat_info->st_uid, stat_info->st_gid);
-
-         /* On a few systems, and in particular, those allowing to give files
-            away, changing the owner or group destroys the suid or sgid bits.
-            So let's attempt setting these bits once more.  */
-         if (stat_info->st_mode & (S_ISUID | S_ISGID | S_ISVTX))
-           set_mode (file_name, stat_info, 0,
-                     invert_permissions, permstatus, typeflag);
+         chown_result = fdchown (file_name, fd,
+                                 st->stat.st_uid, st->stat.st_gid);

        }
        }

+
+      if (chown_result == 0)
+       {
+         /* Changing the owner can flip st_mode bits in some cases, so
+            ignore cur_info if it might be obsolete now.  */
+         if (cur_info
+             && cur_info->st_mode & S_IXUGO
+             && cur_info->st_mode & (S_ISUID | S_ISGID))
+           cur_info = NULL;
+       }
+      else if (chown_result < 0)
+       chown_error_details (file_name,
+                            st->stat.st_uid, st->stat.st_gid);

     }
     }

+
+  if (typeflag != SYMTYPE)
+    set_mode (file_name, &st->stat, fd, cur_info,
+             invert_permissions, permstatus, typeflag);

 }
 
 /* Remember to restore stat attributes (owner, group, mode and times)
 }
 
 /* Remember to restore stat attributes (owner, group, mode and times)

-   for the directory FILE_NAME, using information given in *STAT_INFO,
+   for the directory FILE_NAME, using information given in *ST,

    once we stop extracting files into that directory.
    If not restoring permissions, remember to invert the
    INVERT_PERMISSIONS bits from the file's current permissions.
    once we stop extracting files into that directory.
    If not restoring permissions, remember to invert the
    INVERT_PERMISSIONS bits from the file's current permissions.

-   PERMSTATUS specifies the status of the file's permissions.  */
+   PERMSTATUS specifies the status of the file's permissions.
+
+   NOTICE: this works only if the archive has usual member order, i.e.
+   directory, then the files in that directory. Incremental archive have
+   somewhat reversed order: first go subdirectories, then all other
+   members. To help cope with this case the variable
+   delay_directory_restore_option is set by prepare_to_extract.
+
+   If an archive was explicitely created so that its member order is
+   reversed, some directory timestamps can be restored incorrectly,
+   e.g.:
+       tar --no-recursion -cf archive dir dir/file1 foo dir/file2
+*/

 static void
 static void

-delay_set_stat (char const *file_name, struct stat const *stat_info,
+delay_set_stat (char const *file_name, struct tar_stat_info const *st,

                mode_t invert_permissions, enum permstatus permstatus)
 {
   size_t file_name_len = strlen (file_name);
   struct delayed_set_stat *data =
     xmalloc (offsetof (struct delayed_set_stat, file_name)
             + file_name_len + 1);
                mode_t invert_permissions, enum permstatus permstatus)
 {
   size_t file_name_len = strlen (file_name);
   struct delayed_set_stat *data =
     xmalloc (offsetof (struct delayed_set_stat, file_name)
             + file_name_len + 1);

+  data->next = delayed_set_stat_head;
+  data->dev = st->stat.st_dev;
+  data->ino = st->stat.st_ino;
+  data->mode = st->stat.st_mode;
+  data->uid = st->stat.st_uid;
+  data->gid = st->stat.st_gid;
+  data->atime = st->atime;
+  data->mtime = st->mtime;

   data->file_name_len = file_name_len;
   data->file_name_len = file_name_len;

-  strcpy (data->file_name, file_name);

   data->invert_permissions = invert_permissions;
   data->permstatus = permstatus;
   data->invert_permissions = invert_permissions;
   data->permstatus = permstatus;

-  data->after_symlinks = 0;
-  data->stat_info = *stat_info;
-  data->next = delayed_set_stat_head;
+  data->after_links = 0;
+  data->change_dir = chdir_current;
+  strcpy (data->file_name, file_name);

   delayed_set_stat_head = data;
 }
 
   delayed_set_stat_head = data;
 }
 


@@ -335,9 +431,16 @@ repair_delayed_set_stat (char const *dir,
       if (st.st_dev == dir_stat_info->st_dev
          && st.st_ino == dir_stat_info->st_ino)
        {
       if (st.st_dev == dir_stat_info->st_dev
          && st.st_ino == dir_stat_info->st_ino)
        {

-         data->stat_info = current_stat_info.stat;
+         data->dev = current_stat_info.stat.st_dev;
+         data->ino = current_stat_info.stat.st_ino;
+         data->mode = current_stat_info.stat.st_mode;
+         data->uid = current_stat_info.stat.st_uid;
+         data->gid = current_stat_info.stat.st_gid;
+         data->atime = current_stat_info.atime;
+         data->mtime = current_stat_info.mtime;

          data->invert_permissions =
          data->invert_permissions =

-           (MODE_RWX & (current_stat_info.stat.st_mode ^ st.st_mode));
+           ((current_stat_info.stat.st_mode ^ st.st_mode)
+            & MODE_RWX & ~ current_umask);

          data->permstatus = ARCHIVED_PERMSTATUS;
          return;
        }
          data->permstatus = ARCHIVED_PERMSTATUS;
          return;
        }


@@ -347,21 +450,20 @@ repair_delayed_set_stat (char const *dir,
          quotearg_colon (dir)));
 }
 
          quotearg_colon (dir)));
 }
 

-/* After a file/link/symlink/directory creation has failed, see if
+/* After a file/link/directory creation has failed, see if

    it's because some required directory was not present, and if so,
    create all required directories.  Return non-zero if a directory
    was created.  */
 static int
 make_directories (char *file_name)
 {
    it's because some required directory was not present, and if so,
    create all required directories.  Return non-zero if a directory
    was created.  */
 static int
 make_directories (char *file_name)
 {

-  char *cursor0 = file_name + FILESYSTEM_PREFIX_LEN (file_name);
-  char *cursor;                        /* points into the file name */
+  char *cursor0 = file_name + FILE_SYSTEM_PREFIX_LEN (file_name);
+  char *cursor;                        /* points into the file name */

   int did_something = 0;       /* did we do anything yet? */
   int mode;
   int invert_permissions;
   int status;
 
   int did_something = 0;       /* did we do anything yet? */
   int mode;
   int invert_permissions;
   int status;
 

-

   for (cursor = cursor0; *cursor; cursor++)
     {
       if (! ISSLASH (*cursor))
   for (cursor = cursor0; *cursor; cursor++)
     {
       if (! ISSLASH (*cursor))


@@ -391,7 +493,7 @@ make_directories (char *file_name)
             invert_permissions is zero, because
             repair_delayed_set_stat may need to update the struct.  */
          delay_set_stat (file_name,
             invert_permissions is zero, because
             repair_delayed_set_stat may need to update the struct.  */
          delay_set_stat (file_name,

-                         &current_stat_info.stat /* ignored */,
+                         &current_stat_info,

                          invert_permissions, INTERDIR_PERMSTATUS);
 
          print_for_mkdir (file_name, cursor - file_name, mode);
                          invert_permissions, INTERDIR_PERMSTATUS);
 
          print_for_mkdir (file_name, cursor - file_name, mode);


@@ -426,63 +528,40 @@ file_newer_p (const char *file_name, struct tar_stat_info *tar_stat)
 
   if (stat (file_name, &st))
     {
 
   if (stat (file_name, &st))
     {

-      stat_warn (file_name);
-      return true; /* Be on the safe side */
+      if (errno != ENOENT)
+       {
+         stat_warn (file_name);
+         /* Be on the safe side: if the file does exist assume it is newer */
+         return true;
+       }
+      return false;

     }
   if (!S_ISDIR (st.st_mode)
     }
   if (!S_ISDIR (st.st_mode)

-      && st.st_mtime >= tar_stat->stat.st_mtime)
+      && tar_timespec_cmp (tar_stat->mtime, get_stat_mtime (&st)) <= 0)

     {
       return true;
     }
   return false;
 }
 
     {
       return true;
     }
   return false;
 }
 

-/* Prepare to extract a file.
-   Return zero if extraction should not proceed.  */
-
-static int
-prepare_to_extract (char const *file_name)
-{
-  if (to_stdout_option)
-    return 0;
-
-  switch (old_files_option)
-    {
-    case UNLINK_FIRST_OLD_FILES:
-      if (!remove_any_file (file_name, recursive_unlink_option)
-         && errno && errno != ENOENT)
-       {
-         unlink_error (file_name);
-         return 0;
-       }
-      break;
-
-    case KEEP_NEWER_FILES:
-      if (file_newer_p (file_name, &current_stat_info))
-       {
-         WARN ((0, 0, _("Current `%s' is newer"), file_name));
-         return 0;
-       }
-      break;
-
-    default:
-      break;
-    }
-
-  return 1;
-}
+#define RECOVER_NO 0
+#define RECOVER_OK 1
+#define RECOVER_SKIP 2

 
 /* Attempt repairing what went wrong with the extraction.  Delete an
    already existing file or create missing intermediate directories.
 
 /* Attempt repairing what went wrong with the extraction.  Delete an
    already existing file or create missing intermediate directories.

-   Return nonzero if we somewhat increased our chances at a successful
-   extraction.  errno is properly restored on zero return.  */
+   Return RECOVER_OK if we somewhat increased our chances at a successful
+   extraction, RECOVER_NO if there are no chances, and RECOVER_SKIP if the
+   caller should skip extraction of that member.  The value of errno is
+   properly restored on returning RECOVER_NO.  */
+

 static int
 static int

-maybe_recoverable (char *file_name, int *interdir_made)
+maybe_recoverable (char *file_name, bool *interdir_made)

 {
   int e = errno;
 
   if (*interdir_made)
 {
   int e = errno;
 
   if (*interdir_made)

-    return 0;
+    return RECOVER_NO;

 
   switch (errno)
     {
 
   switch (errno)
     {


@@ -492,13 +571,13 @@ maybe_recoverable (char *file_name, int *interdir_made)
       switch (old_files_option)
        {
        case KEEP_OLD_FILES:
       switch (old_files_option)
        {
        case KEEP_OLD_FILES:

-         return 0;
+         return RECOVER_SKIP;

 
        case KEEP_NEWER_FILES:
          if (file_newer_p (file_name, &current_stat_info))
            {
              errno = e;
 
        case KEEP_NEWER_FILES:
          if (file_newer_p (file_name, &current_stat_info))
            {
              errno = e;

-             return 0;
+             return RECOVER_NO;

            }
          /* FALL THROUGH */
 
            }
          /* FALL THROUGH */
 


@@ -506,9 +585,9 @@ maybe_recoverable (char *file_name, int *interdir_made)
        case NO_OVERWRITE_DIR_OLD_FILES:
        case OVERWRITE_OLD_FILES:
          {
        case NO_OVERWRITE_DIR_OLD_FILES:
        case OVERWRITE_OLD_FILES:
          {

-           int r = remove_any_file (file_name, 0);
+           int r = remove_any_file (file_name, ORDINARY_REMOVE_OPTION);

            errno = EEXIST;
            errno = EEXIST;

-           return r;
+           return r > 0 ? RECOVER_OK : RECOVER_NO;

          }
 
        case UNLINK_FIRST_OLD_FILES:
          }
 
        case UNLINK_FIRST_OLD_FILES:


@@ -520,25 +599,25 @@ maybe_recoverable (char *file_name, int *interdir_made)
       if (! make_directories (file_name))
        {
          errno = ENOENT;
       if (! make_directories (file_name))
        {
          errno = ENOENT;

-         return 0;
+         return RECOVER_NO;

        }
        }

-      *interdir_made = 1;
-      return 1;
+      *interdir_made = true;
+      return RECOVER_OK;

 
     default:
       /* Just say we can't do anything about it...  */
 
 
     default:
       /* Just say we can't do anything about it...  */
 

-      return 0;
+      return RECOVER_NO;

     }
 }
 
 /* Fix the statuses of all directories whose statuses need fixing, and
     }
 }
 
 /* Fix the statuses of all directories whose statuses need fixing, and

-   which are not ancestors of FILE_NAME.  If AFTER_SYMLINKS is
+   which are not ancestors of FILE_NAME.  If AFTER_LINKS is

    nonzero, do this for all such directories; otherwise, stop at the
    first directory that is marked to be fixed up only after delayed
    nonzero, do this for all such directories; otherwise, stop at the
    first directory that is marked to be fixed up only after delayed

-   symlinks are applied.  */
+   links are applied.  */

 static void
 static void

-apply_nonancestor_delayed_set_stat (char const *file_name, bool after_symlinks)
+apply_nonancestor_delayed_set_stat (char const *file_name, bool after_links)

 {
   size_t file_name_len = strlen (file_name);
   bool check_for_renamed_directories = 0;
 {
   size_t file_name_len = strlen (file_name);
   bool check_for_renamed_directories = 0;


@@ -550,9 +629,9 @@ apply_nonancestor_delayed_set_stat (char const *file_name, bool after_symlinks)
       struct stat st;
       struct stat const *cur_info = 0;
 
       struct stat st;
       struct stat const *cur_info = 0;
 

-      check_for_renamed_directories |= data->after_symlinks;
+      check_for_renamed_directories |= data->after_links;

 
 

-      if (after_symlinks < data->after_symlinks
+      if (after_links < data->after_links

          || (data->file_name_len < file_name_len
              && file_name[data->file_name_len]
              && (ISSLASH (file_name[data->file_name_len])
          || (data->file_name_len < file_name_len
              && file_name[data->file_name_len]
              && (ISSLASH (file_name[data->file_name_len])


@@ -560,6 +639,8 @@ apply_nonancestor_delayed_set_stat (char const *file_name, bool after_symlinks)
              && memcmp (file_name, data->file_name, data->file_name_len) == 0))
        break;
 
              && memcmp (file_name, data->file_name, data->file_name_len) == 0))
        break;
 

+      chdir_do (data->change_dir);
+

       if (check_for_renamed_directories)
        {
          cur_info = &st;
       if (check_for_renamed_directories)
        {
          cur_info = &st;


@@ -568,8 +649,7 @@ apply_nonancestor_delayed_set_stat (char const *file_name, bool after_symlinks)
              stat_error (data->file_name);
              skip_this_one = 1;
            }
              stat_error (data->file_name);
              skip_this_one = 1;
            }

-         else if (! (st.st_dev == data->stat_info.st_dev
-                     && (st.st_ino == data->stat_info.st_ino)))
+         else if (! (st.st_dev == data->dev && st.st_ino == data->ino))

            {
              ERROR ((0, 0,
                      _("%s: Directory renamed before its status could be extracted"),
            {
              ERROR ((0, 0,
                      _("%s: Directory renamed before its status could be extracted"),


@@ -579,561 +659,741 @@ apply_nonancestor_delayed_set_stat (char const *file_name, bool after_symlinks)
        }
 
       if (! skip_this_one)
        }
 
       if (! skip_this_one)

-       set_stat (data->file_name, &data->stat_info, cur_info,
-                 data->invert_permissions, data->permstatus, DIRTYPE);
+       {
+         struct tar_stat_info sb;
+         sb.stat.st_mode = data->mode;
+         sb.stat.st_uid = data->uid;
+         sb.stat.st_gid = data->gid;
+         sb.atime = data->atime;
+         sb.mtime = data->mtime;
+         set_stat (data->file_name, &sb, -1, cur_info,
+                   data->invert_permissions, data->permstatus, DIRTYPE);
+       }

 
       delayed_set_stat_head = data->next;
       free (data);
     }
 }
 
 
       delayed_set_stat_head = data->next;
       free (data);
     }
 }
 

-/* Extract a file from the archive.  */
-void
-extract_archive (void)
+\f
+
+/* Extractor functions for various member types */
+
+static int
+extract_dir (char *file_name, int typeflag)

 {
 {

-  union block *data_block;
-  int fd;

   int status;
   int status;

-  size_t count;
-  size_t written;
-  int openflag;

   mode_t mode;
   mode_t mode;

-  off_t size;
-  int interdir_made = 0;
-  char typeflag;
-  char *file_name;
+  bool interdir_made = false;

 
 

-  set_next_block_after (current_header);
-  decode_header (current_header, &current_stat_info, &current_format, 1);
-
-  if (interactive_option && !confirm ("extract", current_stat_info.file_name))
+  /* Save 'root device' to avoid purging mount points. */
+  if (one_file_system_option && root_device == 0)

     {
     {

-      skip_member ();
-      return;
+      struct stat st;
+
+      if (stat (".", &st) != 0)
+       stat_diag (".");
+      else
+       root_device = st.st_dev;

     }
 
     }
 

-  /* Print the block from current_header and current_stat.  */
+  if (incremental_option)
+    /* Read the entry and delete files that aren't listed in the archive.  */
+    purge_directory (file_name);
+  else if (typeflag == GNUTYPE_DUMPDIR)
+    skip_member ();

 
 

-  if (verbose_option)
-    print_header (&current_stat_info, -1);
+  mode = current_stat_info.stat.st_mode | (we_are_root ? 0 : MODE_WXUSR);
+  if (0 < same_owner_option || current_stat_info.stat.st_mode & ~ MODE_RWX)
+    mode &= S_IRWXU;

 
 

-  file_name = safer_name_suffix (current_stat_info.file_name, false);
-  if (strip_name_components)
+  while ((status = mkdir (file_name, mode)))

     {
     {

-      size_t prefix_len = stripped_prefix_len (file_name, strip_name_components);
-      if (prefix_len == (size_t) -1)
+      if (errno == EEXIST
+         && (interdir_made
+             || old_files_option == DEFAULT_OLD_FILES
+             || old_files_option == OVERWRITE_OLD_FILES))

        {
        {

-         skip_member ();
-         return;
+         struct stat st;
+         if (stat (file_name, &st) == 0)
+           {
+             if (interdir_made)
+               {
+                 repair_delayed_set_stat (file_name, &st);
+                 return 0;
+               }
+             if (S_ISDIR (st.st_mode))
+               {
+                 status = 0;
+                 mode = st.st_mode;
+                 break;
+               }
+           }
+         errno = EEXIST;
+       }
+
+      switch (maybe_recoverable (file_name, &interdir_made))
+       {
+       case RECOVER_OK:
+         continue;
+
+       case RECOVER_SKIP:
+         break;
+
+       case RECOVER_NO:
+         if (errno != EEXIST)
+           {
+             mkdir_error (file_name);
+             return 1;
+           }
+         break;

        }
        }

-      file_name += prefix_len;
+      break;

     }
 
     }
 

-  apply_nonancestor_delayed_set_stat (file_name, 0);
+  if (status == 0
+      || old_files_option == DEFAULT_OLD_FILES
+      || old_files_option == OVERWRITE_OLD_FILES)
+    {
+      if (status == 0)
+       delay_set_stat (file_name, &current_stat_info,
+                       ((mode ^ current_stat_info.stat.st_mode)
+                        & MODE_RWX & ~ current_umask),
+                       ARCHIVED_PERMSTATUS);
+      else /* For an already existing directory, invert_perms must be 0 */
+       delay_set_stat (file_name, &current_stat_info,
+                       0,
+                       UNKNOWN_PERMSTATUS);
+    }
+  return status;
+}

 
 

-  /* Take a safety backup of a previously existing file.  */

 
 

-  if (backup_option && !to_stdout_option)
-    if (!maybe_backup_file (file_name, 0))
-      {
-       int e = errno;
-       ERROR ((0, e, _("%s: Was unable to backup this file"),
-               quotearg_colon (file_name)));
-       skip_member ();
-       return;
-      }
+static int
+open_output_file (char *file_name, int typeflag, mode_t mode)
+{
+  int fd;
+  int openflag = (O_WRONLY | O_BINARY | O_CREAT
+                 | (old_files_option == OVERWRITE_OLD_FILES
+                    ? O_TRUNC
+                    : O_EXCL));

 
 

-  /* Extract the archive entry according to its type.  */
+#if O_CTG
+  /* Contiguous files (on the Masscomp) have to specify the size in
+     the open call that creates them.  */

 
 

-  /* KLUDGE */
-  typeflag = sparse_member_p (&current_stat_info) ?
-                  GNUTYPE_SPARSE : current_header->header.typeflag;
+  if (typeflag == CONTTYPE)
+    fd = open (file_name, openflag | O_CTG, mode, current_stat_info.stat.st_size);
+  else
+    fd = open (file_name, openflag, mode);

 
 

-  switch (typeflag)
+#else /* not O_CTG */
+  if (typeflag == CONTTYPE)

     {
     {

-    case GNUTYPE_SPARSE:
-      /* Fall through.  */
+      static int conttype_diagnosed;

 
 

-    case AREGTYPE:
-    case REGTYPE:
-    case CONTTYPE:
+      if (!conttype_diagnosed)
+       {
+         conttype_diagnosed = 1;
+         WARNOPT (WARN_CONTIGUOUS_CAST,
+                  (0, 0, _("Extracting contiguous files as regular files")));
+       }
+    }
+  fd = open (file_name, openflag, mode);

 
 

-      /* Appears to be a file.  But BSD tar uses the convention that a slash
-        suffix means a directory.  */
+#endif /* not O_CTG */

 
 

-      if (current_stat_info.had_trailing_slash)
-       goto really_dir;
+  return fd;
+}

 
 

-      /* FIXME: deal with protection issues.  */
+static int
+extract_file (char *file_name, int typeflag)
+{
+  int fd;
+  off_t size;
+  union block *data_block;
+  int status;
+  size_t count;
+  size_t written;
+  bool interdir_made = false;
+  mode_t mode = current_stat_info.stat.st_mode & MODE_RWX & ~ current_umask;
+  mode_t invert_permissions =
+    0 < same_owner_option ? mode & (S_IRWXG | S_IRWXO) : 0;

 
 

-    again_file:
-      openflag = (O_WRONLY | O_BINARY | O_CREAT
-                 | (old_files_option == OVERWRITE_OLD_FILES
-                    ? O_TRUNC
-                    : O_EXCL));
-      mode = current_stat_info.stat.st_mode & MODE_RWX & ~ current_umask;
+  /* FIXME: deal with protection issues.  */

 
 

-      if (to_stdout_option)
+  if (to_stdout_option)
+    fd = STDOUT_FILENO;
+  else if (to_command_option)
+    {
+      fd = sys_exec_command (file_name, 'f', &current_stat_info);
+      if (fd < 0)

        {
        {

-         fd = STDOUT_FILENO;
-         goto extract_file;
+         skip_member ();
+         return 0;

        }
        }

+    }
+  else
+    {
+      int recover = RECOVER_NO;
+      do
+       fd = open_output_file (file_name, typeflag, mode ^ invert_permissions);
+      while (fd < 0
+            && (recover = maybe_recoverable (file_name, &interdir_made))
+                == RECOVER_OK);

 
 

-      if (! prepare_to_extract (file_name))
+      if (fd < 0)

        {
          skip_member ();
        {
          skip_member ();

-         if (backup_option)
-           undo_last_backup ();
-         break;
+         if (recover == RECOVER_SKIP)
+           return 0;
+         open_error (file_name);
+         return 1;

        }
        }

+    }

 
 

-#if O_CTG
-      /* Contiguous files (on the Masscomp) have to specify the size in
-        the open call that creates them.  */
+  mv_begin_read (&current_stat_info);
+  if (current_stat_info.is_sparse)
+    sparse_extract_file (fd, &current_stat_info, &size);
+  else
+    for (size = current_stat_info.stat.st_size; size > 0; )
+      {
+       mv_size_left (size);

 
 

-      if (typeflag == CONTTYPE)
-       fd = open (file_name, openflag | O_CTG, mode, current_stat_info.stat.st_size);
-      else
-       fd = open (file_name, openflag, mode);
+       /* Locate data, determine max length writeable, write it,
+          block that we have used the data, then check if the write
+          worked.  */

 
 

-#else /* not O_CTG */
-      if (typeflag == CONTTYPE)
-       {
-         static int conttype_diagnosed;
+       data_block = find_next_block ();
+       if (! data_block)
+         {
+           ERROR ((0, 0, _("Unexpected EOF in archive")));
+           break;              /* FIXME: What happens, then?  */
+         }

 
 

-         if (!conttype_diagnosed)
-           {
-             conttype_diagnosed = 1;
-             WARN ((0, 0, _("Extracting contiguous files as regular files")));
-           }
-       }
-      fd = open (file_name, openflag, mode);
+       written = available_space_after (data_block);

 
 

-#endif /* not O_CTG */
+       if (written > size)
+         written = size;
+       errno = 0;
+       count = full_write (fd, data_block->buffer, written);
+       size -= written;

 
 

-      if (fd < 0)
+       set_next_block_after ((union block *)
+                             (data_block->buffer + written - 1));
+       if (count != written)
+         {
+           if (!to_command_option)
+             write_error_details (file_name, count, written);
+           /* FIXME: shouldn't we restore from backup? */
+           break;
+         }
+      }
+
+  skip_file (size);
+
+  mv_end ();
+
+  /* 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 (to_stdout_option)
+    return 0;
+
+  if (! to_command_option)
+    set_stat (file_name, &current_stat_info, fd, NULL, invert_permissions,
+             (old_files_option == OVERWRITE_OLD_FILES
+              ? UNKNOWN_PERMSTATUS : ARCHIVED_PERMSTATUS),
+             typeflag);
+
+  status = close (fd);
+  if (status < 0)
+    close_error (file_name);
+
+  if (to_command_option)
+    sys_wait_command ();
+
+  return status;
+}
+
+/* Create a placeholder file with name FILE_NAME, which will be
+   replaced after other extraction is done by a symbolic link if
+   IS_SYMLINK is true, and by a hard link otherwise.  Set
+   *INTERDIR_MADE if an intermediate directory is made in the
+   process.  */
+
+static int
+create_placeholder_file (char *file_name, bool is_symlink, bool *interdir_made)
+{
+  int fd;
+  struct stat st;
+
+  while ((fd = open (file_name, O_WRONLY | O_CREAT | O_EXCL, 0)) < 0)
+    {
+      switch (maybe_recoverable (file_name, interdir_made))

        {
        {

-         if (maybe_recoverable (file_name, &interdir_made))
-           goto again_file;
+       case RECOVER_OK:
+         continue;
+
+       case RECOVER_SKIP:
+         return 0;

 
 

+       case RECOVER_NO:

          open_error (file_name);
          open_error (file_name);

-         skip_member ();
-         if (backup_option)
-           undo_last_backup ();
-         break;
+         return -1;

        }
        }

+      }

 
 

-    extract_file:
-      if (current_stat_info.is_sparse)
+  if (fstat (fd, &st) != 0)
+    {
+      stat_error (file_name);
+      close (fd);
+    }
+  else if (close (fd) != 0)
+    close_error (file_name);
+  else
+    {
+      struct delayed_set_stat *h;
+      struct delayed_link *p =
+       xmalloc (offsetof (struct delayed_link, target)
+                + strlen (current_stat_info.link_name)
+                + 1);
+      p->next = delayed_link_head;
+      delayed_link_head = p;
+      p->dev = st.st_dev;
+      p->ino = st.st_ino;
+      p->ctime = get_stat_ctime (&st);
+      p->is_symlink = is_symlink;
+      if (is_symlink)

        {
        {

-         sparse_extract_file (fd, &current_stat_info, &size);
+         p->uid = current_stat_info.stat.st_uid;
+         p->gid = current_stat_info.stat.st_gid;
+       }
+      p->change_dir = chdir_current;
+      p->sources = xmalloc (offsetof (struct string_list, string)
+                           + strlen (file_name) + 1);
+      p->sources->next = 0;
+      strcpy (p->sources->string, file_name);
+      strcpy (p->target, current_stat_info.link_name);
+
+      h = delayed_set_stat_head;
+      if (h && ! h->after_links
+         && strncmp (file_name, h->file_name, h->file_name_len) == 0
+         && ISSLASH (file_name[h->file_name_len])
+         && (last_component (file_name) == file_name + h->file_name_len + 1))
+       {
+         do
+           {
+             h->after_links = 1;
+
+             if (stat (h->file_name, &st) != 0)
+               stat_error (h->file_name);
+             else
+               {
+                 h->dev = st.st_dev;
+                 h->ino = st.st_ino;
+               }
+           }
+         while ((h = h->next) && ! h->after_links);

        }
        }

-      else
-       for (size = current_stat_info.stat.st_size; size > 0; )
-         {
-           if (multi_volume_option)
-             {
-               assign_string (&save_name, current_stat_info.file_name);
-               save_totsize = current_stat_info.stat.st_size;
-               save_sizeleft = size;
-             }
-
-           /* Locate data, determine max length writeable, write it,
-              block that we have used the data, then check if the write
-              worked.  */
-
-           data_block = find_next_block ();
-           if (! data_block)
-             {
-               ERROR ((0, 0, _("Unexpected EOF in archive")));
-               break;          /* FIXME: What happens, then?  */
-             }
-
-           written = available_space_after (data_block);
-
-           if (written > size)
-             written = size;
-           errno = 0;
-           count = full_write (fd, data_block->buffer, written);
-           size -= count;
-
-           set_next_block_after ((union block *)
-                                 (data_block->buffer + written - 1));
-           if (count != written)
-             {
-               write_error_details (file_name, count, written);
-               break;
-             }
-         }

 
 

-      skip_file (size);
+      return 0;
+    }
+
+  return -1;
+}

 
 

-      if (multi_volume_option)
-       assign_string (&save_name, 0);
+static int
+extract_link (char *file_name, int typeflag)
+{
+  bool interdir_made = false;
+  char const *link_name;
+  int rc;

 
 

-      /* 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.  */
+  link_name = current_stat_info.link_name;

 
 

-      if (to_stdout_option)
-       break;
+  if (! absolute_names_option && contains_dot_dot (link_name))
+    return create_placeholder_file (file_name, false, &interdir_made);

 
 

-      status = close (fd);
-      if (status < 0)
+  do
+    {
+      struct stat st1, st2;
+      int e;
+      int status = link (link_name, file_name);
+      e = errno;
+
+      if (status == 0)

        {
        {

-         close_error (file_name);
-         if (backup_option)
-           undo_last_backup ();
+         struct delayed_link *ds = delayed_link_head;
+         if (ds && lstat (link_name, &st1) == 0)
+           for (; ds; ds = ds->next)
+             if (ds->change_dir == chdir_current
+                 && ds->dev == st1.st_dev
+                 && ds->ino == st1.st_ino
+                 && timespec_cmp (ds->ctime, get_stat_ctime (&st1)) == 0)
+               {
+                 struct string_list *p =  xmalloc (offsetof (struct string_list, string)
+                                                   + strlen (file_name) + 1);
+                 strcpy (p->string, file_name);
+                 p->next = ds->sources;
+                 ds->sources = p;
+                 break;
+               }
+         return 0;

        }
        }

+      else if ((e == EEXIST && strcmp (link_name, file_name) == 0)
+              || (lstat (link_name, &st1) == 0
+                  && lstat (file_name, &st2) == 0
+                  && st1.st_dev == st2.st_dev
+                  && st1.st_ino == st2.st_ino))
+       return 0;
+
+      errno = e;
+    }
+  while ((rc = maybe_recoverable (file_name, &interdir_made)) == RECOVER_OK);

 
 

-      set_stat (file_name, &current_stat_info.stat, 0, 0,
-               (old_files_option == OVERWRITE_OLD_FILES
-                ? UNKNOWN_PERMSTATUS
-                : ARCHIVED_PERMSTATUS),
-               typeflag);
-      break;
+  if (rc == RECOVER_SKIP)
+    return 0;
+  if (!(incremental_option && errno == EEXIST))
+    {
+      link_error (link_name, file_name);
+      return 1;
+    }
+  return 0;
+}

 
 

-    case SYMTYPE:
+static int
+extract_symlink (char *file_name, int typeflag)
+{

 #ifdef HAVE_SYMLINK
 #ifdef HAVE_SYMLINK

-      if (! prepare_to_extract (file_name))
-       break;
+  bool interdir_made = false;

 
 

-      if (absolute_names_option
-         || ! (ISSLASH (current_stat_info.link_name
-                        [FILESYSTEM_PREFIX_LEN (current_stat_info.link_name)])
-               || contains_dot_dot (current_stat_info.link_name)))
-       {
-         while (status = symlink (current_stat_info.link_name, file_name),
-                status != 0)
-           if (!maybe_recoverable (file_name, &interdir_made))
-             break;
+  if (! absolute_names_option
+      && (IS_ABSOLUTE_FILE_NAME (current_stat_info.link_name)
+         || contains_dot_dot (current_stat_info.link_name)))
+    return create_placeholder_file (file_name, true, &interdir_made);

 
 

-         if (status == 0)
-           set_stat (file_name, &current_stat_info.stat, 0, 0, 0, SYMTYPE);
-         else
-           symlink_error (current_stat_info.link_name, file_name);
-       }
-      else
-       {
-         /* This symbolic link is potentially dangerous.  Don't
-            create it now; instead, create a placeholder file, which
-            will be replaced after other extraction is done.  */
-         struct stat st;
+  while (symlink (current_stat_info.link_name, file_name))
+    switch (maybe_recoverable (file_name, &interdir_made))
+      {
+      case RECOVER_OK:
+       continue;

 
 

-         while (fd = open (file_name, O_WRONLY | O_CREAT | O_EXCL, 0),
-                fd < 0)
-           if (! maybe_recoverable (file_name, &interdir_made))
-             break;
+      case RECOVER_SKIP:
+       return 0;

 
 

-         status = -1;
-         if (fd < 0)
-           open_error (file_name);
-         else if (fstat (fd, &st) != 0)
-           {
-             stat_error (file_name);
-             close (fd);
-           }
-         else if (close (fd) != 0)
-           close_error (file_name);
-         else
-           {
-             struct delayed_set_stat *h;
-             struct delayed_symlink *p =
-               xmalloc (offsetof (struct delayed_symlink, target)
-                        + strlen (current_stat_info.link_name) + 1);
-             p->next = delayed_symlink_head;
-             delayed_symlink_head = p;
-             p->dev = st.st_dev;
-             p->ino = st.st_ino;
-             p->mtime = st.st_mtime;
-             p->uid = current_stat_info.stat.st_uid;
-             p->gid = current_stat_info.stat.st_gid;
-             p->sources = xmalloc (offsetof (struct string_list, string)
-                                   + strlen (file_name) + 1);
-             p->sources->next = 0;
-             strcpy (p->sources->string, file_name);
-             strcpy (p->target, current_stat_info.link_name);
-
-             h = delayed_set_stat_head;
-             if (h && ! h->after_symlinks
-                 && strncmp (file_name, h->file_name, h->file_name_len) == 0
-                 && ISSLASH (file_name[h->file_name_len])
-                 && (base_name (file_name)
-                     == file_name + h->file_name_len + 1))
-               {
-                 do
-                   {
-                     h->after_symlinks = 1;
-
-                     if (stat (h->file_name, &st) != 0)
-                       stat_error (h->file_name);
-                     else
-                       {
-                         h->stat_info.st_dev = st.st_dev;
-                         h->stat_info.st_ino = st.st_ino;
-                       }
-                   }
-                 while ((h = h->next) && ! h->after_symlinks);
-               }
-
-             status = 0;
-           }
-       }
+      case RECOVER_NO:
+       symlink_error (current_stat_info.link_name, file_name);
+       return -1;
+      }

 
 

-      if (status != 0 && backup_option)
-       undo_last_backup ();
-      break;
+  set_stat (file_name, &current_stat_info, -1, NULL, 0, 0, SYMTYPE);
+  return 0;

 
 #else
 
 #else

+  static int warned_once;
+
+  if (!warned_once)
+    {
+      warned_once = 1;
+      WARNOPT (WARN_SYMBOLIC_CAST,
+              (0, 0,
+               _("Attempting extraction of symbolic links as hard links")));
+    }
+  return extract_link (file_name, typeflag);
+#endif
+}
+
+#if S_IFCHR || S_IFBLK
+static int
+extract_node (char *file_name, int typeflag)
+{
+  bool interdir_made = false;
+  mode_t mode = current_stat_info.stat.st_mode & ~ current_umask;
+  mode_t invert_permissions =
+    0 < same_owner_option ? mode & (S_IRWXG | S_IRWXO) : 0;
+
+  while (mknod (file_name, mode ^ invert_permissions,
+               current_stat_info.stat.st_rdev))
+    switch (maybe_recoverable (file_name, &interdir_made))

       {
       {

-       static int warned_once;
+      case RECOVER_OK:
+       continue;

 
 

-       if (!warned_once)
-         {
-           warned_once = 1;
-           WARN ((0, 0,
-                  _("Attempting extraction of symbolic links as hard links")));
-         }
+      case RECOVER_SKIP:
+       return 0;
+
+      case RECOVER_NO:
+       mknod_error (file_name);
+       return -1;

       }
       }

-      typeflag = LNKTYPE;
-      /* Fall through.  */
+
+  set_stat (file_name, &current_stat_info, -1, NULL, invert_permissions,
+           ARCHIVED_PERMSTATUS, typeflag);
+  return 0;
+}

 #endif
 
 #endif
 

-    case LNKTYPE:
-      if (! prepare_to_extract (file_name))
-       break;
+#if HAVE_MKFIFO || defined mkfifo
+static int
+extract_fifo (char *file_name, int typeflag)
+{
+  int status;
+  bool interdir_made = false;
+  mode_t mode = current_stat_info.stat.st_mode & ~ current_umask;
+  mode_t invert_permissions =
+    0 < same_owner_option ? mode & (S_IRWXG | S_IRWXO) : 0;

 
 

-    again_link:
+  while ((status = mkfifo (file_name, mode)) != 0)
+    switch (maybe_recoverable (file_name, &interdir_made))

       {
       {

-       char const *link_name = safer_name_suffix (current_stat_info.link_name,
-                                                  true);
-       struct stat st1, st2;
-       int e;
+      case RECOVER_OK:
+       continue;

 
 

-       /* MSDOS does not implement links.  However, djgpp's link() actually
-          copies the file.  */
-       status = link (link_name, file_name);
+      case RECOVER_SKIP:
+       return 0;

 
 

-       if (status == 0)
-         {
-           struct delayed_symlink *ds = delayed_symlink_head;
-           if (ds && stat (link_name, &st1) == 0)
-             for (; ds; ds = ds->next)
-               if (ds->dev == st1.st_dev
-                   && ds->ino == st1.st_ino
-                   && ds->mtime == st1.st_mtime)
-                 {
-                   struct string_list *p =
-                     xmalloc (offsetof (struct string_list, string)
-                              + strlen (file_name) + 1);
-                   strcpy (p->string, file_name);
-                   p->next = ds->sources;
-                   ds->sources = p;
-                   break;
-                 }
-           break;
-         }
-       if (maybe_recoverable (file_name, &interdir_made))
-         goto again_link;
+      case RECOVER_NO:
+       mkfifo_error (file_name);
+       return -1;
+      }

 
 

-       if (incremental_option && errno == EEXIST)
-         break;
-       e = errno;
-       if (stat (link_name, &st1) == 0
-           && stat (file_name, &st2) == 0
-           && st1.st_dev == st2.st_dev
-           && st1.st_ino == st2.st_ino)
-         break;
+  set_stat (file_name, &current_stat_info, -1, NULL, invert_permissions,
+           ARCHIVED_PERMSTATUS, typeflag);
+  return 0;
+}
+#endif

 
 

-       link_error (link_name, file_name);
-       if (backup_option)
-         undo_last_backup ();
-      }
+static int
+extract_volhdr (char *file_name, int typeflag)
+{
+  skip_member ();
+  return 0;
+}
+
+static int
+extract_failure (char *file_name, int typeflag)
+{
+  return 1;
+}
+
+typedef int (*tar_extractor_t) (char *file_name, int typeflag);
+
+\f
+
+/* Prepare to extract a file. Find extractor function.
+   Return zero if extraction should not proceed.  */
+
+static int
+prepare_to_extract (char const *file_name, int typeflag, tar_extractor_t *fun)
+{
+  int rc = 1;
+
+  if (EXTRACT_OVER_PIPE)
+    rc = 0;
+
+  /* Select the extractor */
+  switch (typeflag)
+    {
+    case GNUTYPE_SPARSE:
+      *fun = extract_file;
+      rc = 1;
+      break;
+
+    case AREGTYPE:
+    case REGTYPE:
+    case CONTTYPE:
+      /* Appears to be a file.  But BSD tar uses the convention that a slash
+        suffix means a directory.  */
+      if (current_stat_info.had_trailing_slash)
+       *fun = extract_dir;
+      else
+       {
+         *fun = extract_file;
+         rc = 1;
+       }
+      break;
+
+    case SYMTYPE:
+      *fun = extract_symlink;
+      break;
+
+    case LNKTYPE:
+      *fun = extract_link;

       break;
 
 #if S_IFCHR
     case CHRTYPE:
       current_stat_info.stat.st_mode |= S_IFCHR;
       break;
 
 #if S_IFCHR
     case CHRTYPE:
       current_stat_info.stat.st_mode |= S_IFCHR;

-      goto make_node;
+      *fun = extract_node;
+      break;

 #endif
 
 #if S_IFBLK
     case BLKTYPE:
       current_stat_info.stat.st_mode |= S_IFBLK;
 #endif
 
 #if S_IFBLK
     case BLKTYPE:
       current_stat_info.stat.st_mode |= S_IFBLK;

-#endif
-
-#if S_IFCHR || S_IFBLK
-    make_node:
-      if (! prepare_to_extract (file_name))
-       break;
-
-      status = mknod (file_name, current_stat_info.stat.st_mode,
-                     current_stat_info.stat.st_rdev);
-      if (status != 0)
-       {
-         if (maybe_recoverable (file_name, &interdir_made))
-           goto make_node;
-         mknod_error (file_name);
-         if (backup_option)
-           undo_last_backup ();
-         break;
-       };
-      set_stat (file_name, &current_stat_info.stat, 0, 0,
-               ARCHIVED_PERMSTATUS, typeflag);
+      *fun = extract_node;

       break;
 #endif
 
 #if HAVE_MKFIFO || defined mkfifo
     case FIFOTYPE:
       break;
 #endif
 
 #if HAVE_MKFIFO || defined mkfifo
     case FIFOTYPE:

-      if (! prepare_to_extract (file_name))
-       break;
-
-      while (status = mkfifo (file_name, current_stat_info.stat.st_mode),
-            status != 0)
-       if (!maybe_recoverable (file_name, &interdir_made))
-         break;
-
-      if (status == 0)
-       set_stat (file_name, &current_stat_info.stat, NULL, 0,
-                 ARCHIVED_PERMSTATUS, typeflag);
-      else
-       {
-         mkfifo_error (file_name);
-         if (backup_option)
-           undo_last_backup ();
-       }
+      *fun = extract_fifo;

       break;
 #endif
 
     case DIRTYPE:
     case GNUTYPE_DUMPDIR:
       break;
 #endif
 
     case DIRTYPE:
     case GNUTYPE_DUMPDIR:

-    really_dir:
-      if (incremental_option)
-       {
-         /* Read the entry and delete files that aren't listed in the
-            archive.  */
-
-         gnu_restore (file_name);
-       }
-      else if (typeflag == GNUTYPE_DUMPDIR)
-       skip_member ();
-
-      mode = ((current_stat_info.stat.st_mode
-              | (we_are_root ? 0 : MODE_WXUSR))
-             & MODE_RWX);
-
-      status = prepare_to_extract (file_name);
-      if (status == 0)
-       break;
-      if (status < 0)
-       goto directory_exists;
-
-    again_dir:
-      status = mkdir (file_name, mode);
-
-      if (status != 0)
-       {
-         if (errno == EEXIST
-             && (interdir_made
-                 || old_files_option == DEFAULT_OLD_FILES
-                 || old_files_option == OVERWRITE_OLD_FILES))
-           {
-             struct stat st;
-             if (stat (file_name, &st) == 0)
-               {
-                 if (interdir_made)
-                   {
-                     repair_delayed_set_stat (file_name, &st);
-                     break;
-                   }
-                 if (S_ISDIR (st.st_mode))
-                   {
-                     mode = st.st_mode & ~ current_umask;
-                     goto directory_exists;
-                   }
-               }
-             errno = EEXIST;
-           }
-
-         if (maybe_recoverable (file_name, &interdir_made))
-           goto again_dir;
-
-         if (errno != EEXIST)
-           {
-             mkdir_error (file_name);
-             if (backup_option)
-               undo_last_backup ();
-             break;
-           }
-       }
-
-    directory_exists:
-      if (status == 0
-         || old_files_option == DEFAULT_OLD_FILES
-         || old_files_option == OVERWRITE_OLD_FILES)
-       delay_set_stat (file_name, &current_stat_info.stat,
-                       MODE_RWX & (mode ^ current_stat_info.stat.st_mode),
-                       (status == 0
-                        ? ARCHIVED_PERMSTATUS
-                        : UNKNOWN_PERMSTATUS));
+      *fun = extract_dir;
+      if (current_stat_info.is_dumpdir)
+       delay_directory_restore_option = true;

       break;
 
     case GNUTYPE_VOLHDR:
       break;
 
     case GNUTYPE_VOLHDR:

-      if (verbose_option)
-       fprintf (stdlis, _("Reading %s\n"), quote (current_stat_info.file_name));
-      break;
-
-    case GNUTYPE_NAMES:
-      extract_mangle ();
+      *fun = extract_volhdr;

       break;
 
     case GNUTYPE_MULTIVOL:
       ERROR ((0, 0,
              _("%s: Cannot extract -- file is continued from another volume"),
              quotearg_colon (current_stat_info.file_name)));
       break;
 
     case GNUTYPE_MULTIVOL:
       ERROR ((0, 0,
              _("%s: Cannot extract -- file is continued from another volume"),
              quotearg_colon (current_stat_info.file_name)));

-      skip_member ();
-      if (backup_option)
-       undo_last_backup ();
+      *fun = extract_failure;

       break;
 
     case GNUTYPE_LONGNAME:
     case GNUTYPE_LONGLINK:
       break;
 
     case GNUTYPE_LONGNAME:
     case GNUTYPE_LONGLINK:

-      ERROR ((0, 0, _("Visible long name error")));
-      skip_member ();
-      if (backup_option)
-       undo_last_backup ();
+      ERROR ((0, 0, _("Unexpected long name header")));
+      *fun = extract_failure;
+      break;
+
+    default:
+      WARNOPT (WARN_UNKNOWN_CAST,
+              (0, 0,
+               _("%s: Unknown file type `%c', extracted as normal file"),
+               quotearg_colon (file_name), typeflag));
+      *fun = extract_file;
+    }
+
+  /* Determine whether the extraction should proceed */
+  if (rc == 0)
+    return 0;
+
+  switch (old_files_option)
+    {
+    case UNLINK_FIRST_OLD_FILES:
+      if (!remove_any_file (file_name,
+                            recursive_unlink_option ? RECURSIVE_REMOVE_OPTION
+                                                      : ORDINARY_REMOVE_OPTION)
+         && errno && errno != ENOENT)
+       {
+         unlink_error (file_name);
+         return 0;
+       }
+      break;
+
+    case KEEP_NEWER_FILES:
+      if (file_newer_p (file_name, &current_stat_info))
+       {
+         WARNOPT (WARN_IGNORE_NEWER,
+                  (0, 0, _("Current %s is newer or same age"),
+                   quote (file_name)));
+         return 0;
+       }

       break;
 
     default:
       break;
 
     default:

-      WARN ((0, 0,
-            _("%s: Unknown file type '%c', extracted as normal file"),
-            quotearg_colon (file_name), typeflag));
-      goto again_file;
+      break;
+    }
+
+  return 1;
+}
+
+/* Extract a file from the archive.  */
+void
+extract_archive (void)
+{
+  char typeflag;
+  tar_extractor_t fun;
+
+  fatal_exit_hook = extract_finish;
+
+  set_next_block_after (current_header);
+
+  if (!current_stat_info.file_name[0]
+      || (interactive_option
+         && !confirm ("extract", current_stat_info.file_name)))
+    {
+      skip_member ();
+      return;
+    }
+
+  /* Print the block from current_header and current_stat.  */
+  if (verbose_option)
+    print_header (&current_stat_info, current_header, -1);
+
+  /* Restore stats for all non-ancestor directories, unless
+     it is an incremental archive.
+     (see NOTICE in the comment to delay_set_stat above) */
+  if (!delay_directory_restore_option)
+    {
+      int dir = chdir_current;
+      apply_nonancestor_delayed_set_stat (current_stat_info.file_name, 0);
+      chdir_do (dir);
+    }
+
+  /* Take a safety backup of a previously existing file.  */
+
+  if (backup_option)
+    if (!maybe_backup_file (current_stat_info.file_name, 0))
+      {
+       int e = errno;
+       ERROR ((0, e, _("%s: Was unable to backup this file"),
+               quotearg_colon (current_stat_info.file_name)));
+       skip_member ();
+       return;
+      }
+
+  /* Extract the archive entry according to its type.  */
+  /* KLUDGE */
+  typeflag = sparse_member_p (&current_stat_info) ?
+                  GNUTYPE_SPARSE : current_header->header.typeflag;
+
+  if (prepare_to_extract (current_stat_info.file_name, typeflag, &fun))
+    {
+      if (fun && (*fun) (current_stat_info.file_name, typeflag)
+         && backup_option)
+       undo_last_backup ();

     }
     }

+  else
+    skip_member ();
+

 }
 
 }
 

-/* Extract the symbolic links whose final extraction were delayed.  */
+/* Extract the links whose final extraction were delayed.  */

 static void
 static void

-apply_delayed_symlinks (void)
+apply_delayed_links (void)

 {
 {

-  struct delayed_symlink *ds;
+  struct delayed_link *ds;

 
 

-  for (ds = delayed_symlink_head; ds; )
+  for (ds = delayed_link_head; ds; )

     {
       struct string_list *sources = ds->sources;
       char const *valid_source = 0;
 
     {
       struct string_list *sources = ds->sources;
       char const *valid_source = 0;
 

+      chdir_do (ds->change_dir);
+

       for (sources = ds->sources; sources; sources = sources->next)
        {
          char const *source = sources->string;
          struct stat st;
 
          /* Make sure the placeholder file is still there.  If not,
       for (sources = ds->sources; sources; sources = sources->next)
        {
          char const *source = sources->string;
          struct stat st;
 
          /* Make sure the placeholder file is still there.  If not,

-            don't create a symlink, as the placeholder was probably
+            don't create a link, as the placeholder was probably

             removed by a later extraction.  */
          if (lstat (source, &st) == 0
              && st.st_dev == ds->dev
              && st.st_ino == ds->ino
             removed by a later extraction.  */
          if (lstat (source, &st) == 0
              && st.st_dev == ds->dev
              && st.st_ino == ds->ino

-             && st.st_mtime == ds->mtime)
+             && timespec_cmp (get_stat_ctime (&st), ds->ctime) == 0)

            {
              /* Unlink the placeholder, then create a hard link if possible,
                 a symbolic link otherwise.  */
            {
              /* Unlink the placeholder, then create a hard link if possible,
                 a symbolic link otherwise.  */


@@ -1141,14 +1401,20 @@ apply_delayed_symlinks (void)
                unlink_error (source);
              else if (valid_source && link (valid_source, source) == 0)
                ;
                unlink_error (source);
              else if (valid_source && link (valid_source, source) == 0)
                ;

+             else if (!ds->is_symlink)
+               {
+                 if (link (ds->target, source) != 0)
+                   link_error (ds->target, source);
+               }

              else if (symlink (ds->target, source) != 0)
                symlink_error (ds->target, source);
              else
                {
              else if (symlink (ds->target, source) != 0)
                symlink_error (ds->target, source);
              else
                {

+                 struct tar_stat_info st1;
+                 st1.stat.st_uid = ds->uid;
+                 st1.stat.st_gid = ds->gid;
+                 set_stat (source, &st1, -1, NULL, 0, 0, SYMTYPE);

                  valid_source = source;
                  valid_source = source;

-                 st.st_uid = ds->uid;
-                 st.st_gid = ds->gid;
-                 set_stat (source, &st, 0, 0, 0, SYMTYPE);

                }
            }
        }
                }
            }
        }


@@ -1161,13 +1427,13 @@ apply_delayed_symlinks (void)
        }
 
       {
        }
 
       {

-       struct delayed_symlink *next = ds->next;
+       struct delayed_link *next = ds->next;

        free (ds);
        ds = next;
       }
     }
 
        free (ds);
        ds = next;
       }
     }
 

-  delayed_symlink_head = 0;
+  delayed_link_head = 0;

 }
 
 /* Finish the extraction of an archive.  */
 }
 
 /* Finish the extraction of an archive.  */


@@ -1177,19 +1443,44 @@ extract_finish (void)
   /* First, fix the status of ordinary directories that need fixing.  */
   apply_nonancestor_delayed_set_stat ("", 0);
 
   /* First, fix the status of ordinary directories that need fixing.  */
   apply_nonancestor_delayed_set_stat ("", 0);
 

-  /* Then, apply delayed symlinks, so that they don't affect delayed
+  /* Then, apply delayed links, so that they don't affect delayed

      directory status-setting for ordinary directories.  */
      directory status-setting for ordinary directories.  */

-  apply_delayed_symlinks ();
+  apply_delayed_links ();

 
   /* Finally, fix the status of directories that are ancestors
 
   /* Finally, fix the status of directories that are ancestors

-     of delayed symlinks.  */
+     of delayed links.  */

   apply_nonancestor_delayed_set_stat ("", 1);
 }
 
   apply_nonancestor_delayed_set_stat ("", 1);
 }
 

-void
-fatal_exit (void)
+bool
+rename_directory (char *src, char *dst)

 {
 {

-  extract_finish ();
-  error (TAREXIT_FAILURE, 0, _("Error is not recoverable: exiting now"));
-  abort ();
+  if (rename (src, dst))
+    {
+      int e = errno;
+
+      switch (e)
+       {
+       case ENOENT:
+         if (make_directories (dst))
+           {
+             if (rename (src, dst) == 0)
+               return true;
+             e = errno;
+           }
+         break;
+
+       case EXDEV:
+         /* FIXME: Fall back to recursive copying */
+
+       default:
+         break;
+       }
+
+      ERROR ((0, e, _("Cannot rename %s to %s"),
+             quote_n (0, src),
+             quote_n (1, dst)));
+      return false;
+    }
+  return true;

 }
 }