Fix --delay-directory-restore on archives with reversed member ordering.

* src/extract.c (find_direct_ancestor): Remove useless test.
(delay_set_stat): If the file name being added is already in
the list, update stored data instead of creating a new entry.
This works for archives with reversed order of members.
* tests/extrac22.at: New testcase.
* tests/Makefile.am: Add new testcase.
* tests/testsuite.at: Include new testcase.

src/extract.c

@@ -400,7 +400,7 @@ find_direct_ancestor (char const *file_name)
   struct delayed_set_stat *h = delayed_set_stat_head;
   while (h)
     {
-      if (h && ! h->after_links
+      if (! 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))
@@ -458,25 +458,56 @@ delay_set_stat (char const *file_name, struct tar_stat_info const *st,
 		mode_t mode, int atflag)
 {
   size_t file_name_len = strlen (file_name);
-  struct delayed_set_stat *data = xmalloc (sizeof (*data));
-  data->next = delayed_set_stat_head;
+  struct delayed_set_stat *data;
+
+  for (data = delayed_set_stat_head; data; data = data->next)
+    if (strcmp (data->file_name, file_name) == 0)
+      break;
+
+  if (data)
+    {
+      if (data->interdir)
+	{
+	  struct stat real_st;
+	  if (fstatat (chdir_fd, data->file_name,
+		       &real_st, data->atflag) != 0)
+	    {
+	      stat_error (data->file_name);
+	    }
+	  else
+	    {
+	      data->dev = real_st.st_dev;
+	      data->ino = real_st.st_ino;
+	    }
+	}
+    }
+  else
+    {
+      data = xmalloc (sizeof (*data));
+      data->next = delayed_set_stat_head;
+      delayed_set_stat_head = data;
+      data->file_name_len = file_name_len;
+      data->file_name = xstrdup (file_name);
+      data->after_links = false;
+      if (st)
+	{
+	  data->dev = st->stat.st_dev;
+	  data->ino = st->stat.st_ino;
+	}
+    }
+
   data->mode = mode;
   if (st)
     {
-      data->dev = st->stat.st_dev;
-      data->ino = st->stat.st_ino;
       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 = xstrdup (file_name);
   data->current_mode = current_mode;
   data->current_mode_mask = current_mode_mask;
   data->interdir = ! st;
   data->atflag = atflag;
-  data->after_links = 0;
   data->change_dir = chdir_current;
   data->cntx_name = NULL;
   if (st)
@@ -508,8 +539,6 @@ delay_set_stat (char const *file_name, struct tar_stat_info const *st,
       data->xattr_map = NULL;
       data->xattr_map_size = 0;
     }
-  strcpy (data->file_name, file_name);
-  delayed_set_stat_head = data;
   if (must_be_dot_or_slash (file_name))
     mark_after_links (data);
 }
@@ -523,7 +552,7 @@ repair_delayed_set_stat (char const *dir,
 			 struct stat const *dir_stat_info)
 {
   struct delayed_set_stat *data;
-  for (data = delayed_set_stat_head;  data;  data = data->next)
+  for (data = delayed_set_stat_head; data; data = data->next)
     {
       struct stat st;
       if (fstatat (chdir_fd, data->file_name, &st, data->atflag) != 0)

tests/Makefile.am

@@ -120,6 +120,7 @@ TESTSUITE_AT = \
  extrac19.at\
  extrac20.at\
  extrac21.at\
+ extrac22.at\
  filerem01.at\
  filerem02.at\
  dirrem01.at\

tests/extrac22.at

@@ -0,0 +1,60 @@
+# Test suite for GNU tar.                             -*- Autotest -*-
+# Copyright 2017-2019 Free Software Foundation, Inc.
+#
+# 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 3 of the License, 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+
+AT_SETUP([delay-directory-restore on reversed ordering])
+
+# The --delay-directory-resore option worked incorrectly on archives with
+# reversed member ordering (which was documented, anyway). This is illustrated
+# in
+#   http://lists.gnu.org/archive/html/bug-tar/2019-03/msg00022.html
+# which was taken as a base for this testcase.
+# The bug affected tar versions <= 1.32.
+
+AT_KEYWORDS([extract extrac22 delay delay-reversed])
+AT_TAR_CHECK([
+AT_UNPRIVILEGED_PREREQ
+AT_SORT_PREREQ
+mkdir t
+(cd t
+ genfile --length 100 --file data1
+ mkdir dir1
+ cp data1 dir1
+ mkdir dir2
+ cd dir2
+ ln -s ../dir1/data1 data2
+ cd ..
+ chmod -w dir2)
+
+AT_DATA([filelist],
+[./dir2/data2
+./dir2
+./dir1/data1
+./dir1
+./data1
+])
+
+tar -C t -c -f a.tar --no-recursion -T filelist
+
+mkdir restore
+tar -x -p --delay-directory-restore -C restore -f a.tar
+# Previous versions of tar would fail here with the following diagnostics:
+# tar: ./dir2/data2: Cannot unlink: Permission denied
+],
+[0],
+[])
+AT_CLEANUP

tests/testsuite.at

@@ -342,6 +342,7 @@ m4_include([extrac18.at])
 m4_include([extrac19.at])
 m4_include([extrac20.at])
 m4_include([extrac21.at])
+m4_include([extrac22.at])
 
 m4_include([backup01.at])