Improve tar_getcwd

* src/common.h (tar_getcwd): Return pointer is const.
* src/misc.c (wd) <cwd>: New member.
(chdir_arg): Initialize cwd.
(tar_getcwd): Use cwd member to cache the result.  Take into
account absolute pathnames,
(normalize_filename): Don't free the value
returned from tar_getcwd.
* src/names.c (name_next_elt): Remove leftover call chdir().
* tests/Makefile.am: Add new tests.
* tests/testsuite.at: Likewise.

* tests/incr08.at: New testcase.
* tests/remfiles04.at: New testcase.
* tests/remfiles05.at: New testcase.
* tests/remfiles06.at: New testcase.
* tests/remfiles07.at: New testcase.

src/common.h

@@ -608,7 +608,7 @@ char *namebuf_name (namebuf_t buf, const char *name);
 void namebuf_add_dir (namebuf_t buf, const char *name);
 char *namebuf_finish (namebuf_t buf);
 
-char *tar_getcwd (void);
+const char *tar_getcwd (void);
 
 /* Represent N using a signed integer I such that (uintmax_t) I == N.
    With a good optimizing compiler, this is equivalent to (intmax_t) i

src/misc.c

@@ -283,21 +283,20 @@ normalize_filename (const char *name)
          getcwd is slow, it might fail, and it does not necessarily
          return a canonical name even when it succeeds.  Perhaps we
          can use dev+ino pairs instead of names?  */
-      copy = tar_getcwd ();
-      if (copy)
-        {
-          size_t copylen = strlen (copy);
-          bool need_separator = ! (DOUBLE_SLASH_IS_DISTINCT_ROOT
-                                   && copylen == 2 && ISSLASH (copy[1]));
-          copy = xrealloc (copy, copylen + need_separator + strlen (name) + 1);
-          copy[copylen] = DIRECTORY_SEPARATOR;
-          strcpy (copy + copylen + need_separator, name);
-        }
-      else
-        WARN ((0, errno, _("Cannot get working directory")));
+      const char *cwd = tar_getcwd ();
+      size_t copylen;
+      bool need_separator;
+      
+      copylen = strlen (cwd);
+      need_separator = ! (DOUBLE_SLASH_IS_DISTINCT_ROOT
+			  && copylen == 2 && ISSLASH (cwd[1]));
+      copy = xmalloc (copylen + need_separator + strlen (name) + 1);
+      strcpy (copy, cwd);
+      copy[copylen] = DIRECTORY_SEPARATOR;
+      strcpy (copy + copylen + need_separator, name);
     }
 
-  if (! copy)
+  if (!copy)
     copy = xstrdup (name);
   normalize_filename_x (copy);
   return copy;
@@ -831,7 +830,8 @@ struct wd
 {
   /* The directory's name.  */
   char const *name;
-
+  /* Current working directory; initialized by tar_getcwd */
+  char *cwd; 
   /* If nonzero, the file descriptor of the directory, or AT_FDCWD if
      the working directory.  If zero, the directory needs to be opened
      to be used.  */
@@ -886,6 +886,7 @@ chdir_arg (char const *dir)
       if (! wd_count)
 	{
 	  wd[wd_count].name = ".";
+	  wd[wd_count].cwd = NULL;
 	  wd[wd_count].fd = AT_FDCWD;
 	  wd_count++;
 	}
@@ -903,6 +904,7 @@ chdir_arg (char const *dir)
     }
 
   wd[wd_count].name = dir;
+  wd[wd_count].cwd = NULL;
   wd[wd_count].fd = 0;
   return wd_count++;
 }
@@ -976,7 +978,7 @@ chdir_do (int i)
     }
 }
 
-char *
+const char *
 tar_getcwd (void)
 {
   static char *cwd;
@@ -985,10 +987,27 @@ tar_getcwd (void)
 
   if (!cwd)
     cwd = xgetcwd ();
-  nbuf = namebuf_create (cwd);
-  for (i = 1; i <= chdir_current; i++)
-    namebuf_add_dir (nbuf, wd[i].name);
-  return namebuf_finish (nbuf);
+  if (!wd)
+    return cwd;
+  
+  if (0 == chdir_current || !wd[chdir_current].cwd)
+    {
+      if (IS_ABSOLUTE_FILE_NAME (wd[chdir_current].name))
+	return wd[chdir_current].name;
+      
+      if (!wd[0].cwd)
+	wd[0].cwd = cwd;
+
+      for (i = chdir_current - 1; i > 0; i--)
+	if (wd[i].cwd)
+	  break;
+      
+      nbuf = namebuf_create (wd[i].cwd);
+      for (i++; i <= chdir_current; i++)
+	namebuf_add_dir (nbuf, wd[i].name);
+      wd[chdir_current].cwd = namebuf_finish (nbuf);
+    }
+  return wd[chdir_current].cwd;
 }
 
 void

src/names.c

@@ -578,13 +578,11 @@ name_next_elt (int change_dirs)
 	case NELT_CHDIR:
 	  if (change_dirs)
 	    {
-	      copy_name (ep);
-	      if (chdir (name_buffer) < 0)
-		chdir_fatal (name_buffer);
+	      chdir_do (chdir_arg (xstrdup (ep->v.name)));
 	      name_list_advance ();
 	      break;
 	    }
-	  /* fall trhough */
+	  /* fall through */
 	case NELT_NAME:
 	  copy_name (ep);
 	  if (unquote_option)

tests/Makefile.am

@@ -112,6 +112,7 @@ TESTSUITE_AT = \
  incr05.at\
  incr06.at\
  incr07.at\
+ incr08.at\
  indexfile.at\
  ignfail.at\
  label01.at\
@@ -161,6 +162,10 @@ TESTSUITE_AT = \
  remfiles01.at\
  remfiles02.at\
  remfiles03.at\
+ remfiles04.at\
+ remfiles05.at\
+ remfiles06.at\
+ remfiles07.at\
  same-order01.at\
  same-order02.at\
  shortfile.at\

tests/incr08.at

@@ -0,0 +1,86 @@
+# Process this file with autom4te to create testsuite. -*- Autotest -*-
+# Test suite for GNU tar.
+# Copyright 2013 Free Software Foundation, Inc.
+#
+# 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/>.
+
+# Description: In tar 1.26 listed-incremental with -C and absolute path
+# would malfunction under certain conditions due to buggy filename
+# normalization.
+#
+# The value returned by normalize_filename() is used to populate the "caname"
+# field in both the "directory" structure in incremen.c and the "name"
+# structure in names.c, and in both cases that field is then used in the
+# "hash" and "compare" functions for the related hash tables.  Thus, the
+# fact that the returned value doesn't reflect the operation of previous
+# "-C" options means that it's possible for two different directories to
+# be given the same "caname" value in the hashed structure and thus end up
+# being confused with each other.
+#
+# The bug is triggered when dumping both relative paths after -C and
+# absolute paths that match the process' current working directory.
+#
+# Reported by: Nathan Stratton Treadway <nathanst@ontko.com>
+# References: <20130922192135.GJ32256@shire.ontko.com>,
+#             http://lists.gnu.org/archive/html/bug-tar/2013-09/msg00034.html
+
+AT_SETUP([filename normalization])
+AT_KEYWORDS([incremental create incr08])
+
+AT_TAR_CHECK([
+AT_SORT_PREREQ
+mkdir tartest
+cd tartest
+mkdir foo
+mkdir foo/subdir
+mkdir foo/subdir/dir1
+mkdir subdir
+mkdir subdir/dir2
+decho A
+find|sort
+
+decho B
+DIR=`pwd`
+tar -cvf ../foo.tar --listed-incremental=../foo.snar -C foo . $DIR 2>../err |\
+  sed "s|$DIR|ABSPATH|"
+sed "s|$DIR|ABSPATH|" ../err >&2
+],
+[0],
+[A
+.
+./foo
+./foo/subdir
+./foo/subdir/dir1
+./subdir
+./subdir/dir2
+B
+./
+./subdir/
+./subdir/dir1/
+ABSPATH/
+ABSPATH/subdir/
+ABSPATH/subdir/dir2/
+],
+[A
+B
+tar: .: Directory is new
+tar: ./subdir: Directory is new
+tar: ./subdir/dir1: Directory is new
+tar: ABSPATH: Directory is new
+tar: ABSPATH/subdir: Directory is new
+tar: ABSPATH/subdir/dir2: Directory is new
+tar: Removing leading `/' from member names
+],[],[],[gnu])
+
+AT_CLEANUP

tests/remfiles04.at

@@ -0,0 +1,53 @@
+# Process this file with autom4te to create testsuite. -*- Autotest -*-
+# Test suite for GNU tar.
+# Copyright 2013 Free Software Foundation, Inc.
+#
+# 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/>.
+
+# Description: Tar 1.26 would remove wrong files when called with
+# --remove-files and -C
+# Reported by: Jörgen Strand <Jorgen.Strand@sonymobile.com>
+# References: <9FC79E5CB90CEC47B9647DCAB7BD327A01AD83B452EE@seldmbx02.corpusers.net>
+#             http://lists.gnu.org/archive/html/bug-tar/2013-09/msg00024.html
+
+AT_SETUP([remove-files with -C])
+AT_KEYWORDS([create remove-files remfiles04])
+
+AT_TAR_CHECK([
+AT_SORT_PREREQ
+mkdir foo
+echo bar > bar
+echo foobar > foo/bar
+tar -cf foo.tar --remove-files -C foo bar
+echo A
+find . | sort
+echo foobar > foo/bar
+tar -rf foo.tar --remove-files -C foo bar
+echo B
+find . | sort
+],
+[0],
+[A
+.
+./bar
+./foo
+./foo.tar
+B
+.
+./bar
+./foo
+./foo.tar
+],[],[],[],[gnu])
+
+AT_CLEANUP

tests/remfiles05.at

@@ -0,0 +1,60 @@
+# Process this file with autom4te to create testsuite. -*- Autotest -*-
+# Test suite for GNU tar.
+# Copyright 2013 Free Software Foundation, Inc.
+#
+# 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/>.
+
+# Description: Tar 1.26 would remove wrong files when invoked with
+# --listed-incremental and -C
+# Reported by: Nathan Stratton Treadway <nathanst@ontko.com>
+# References: <20130921171234.GG32256@shire.ontko.com>,
+#             http://lists.gnu.org/archive/html/bug-tar/2013-09/msg00028.html
+
+AT_SETUP([incremental and -C])
+AT_KEYWORDS([incremental create remove-files remfiles05])
+
+AT_TAR_CHECK([
+AT_SORT_PREREQ
+mkdir foo
+echo bar > bar
+echo foo/bar > foo/bar
+decho A
+find . | sort
+
+decho B
+tar -cvf foo.tar --listed-incremental=foo.snar --remove-files -C foo bar
+decho C
+find . | sort
+],
+[0],
+[A
+.
+./bar
+./foo
+./foo/bar
+B
+bar
+C
+.
+./bar
+./foo
+./foo.snar
+./foo.tar
+],
+[A
+B
+C
+],[],[],[gnu])
+
+AT_CLEANUP

tests/remfiles06.at

@@ -0,0 +1,65 @@
+# Process this file with autom4te to create testsuite. -*- Autotest -*-
+# Test suite for GNU tar.
+# Copyright 2013 Free Software Foundation, Inc.
+#
+# 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/>.
+
+# Description: There was a leftover call to chdir in name_next_elt() in
+# tar 1.26.  After commit e3d28d84 this call would confuse the tar_getcwd
+# function.
+# Reported by: Nathan Stratton Treadway <nathanst@ontko.com>
+# References: <20130924145657.GM32256@shire.ontko.com>,
+#             http://lists.gnu.org/archive/html/bug-tar/2013-09/msg00045.html
+
+AT_SETUP([incremental with two -C])
+AT_KEYWORDS([incremental create remove-files remfiles06])
+
+AT_TAR_CHECK([
+AT_SORT_PREREQ
+mkdir tartest
+cd tartest
+mkdir foo
+echo foo/file > foo/file
+mkdir bar
+echo bar/file > bar/file
+decho A
+find|sort
+
+decho B
+tar -cvf ../foo.tar --remove-files -C foo file -C ../bar file
+
+decho C
+find|sort
+],
+[0],
+[A
+.
+./bar
+./bar/file
+./foo
+./foo/file
+B
+file
+file
+C
+.
+./bar
+./foo
+],
+[A
+B
+C
+],[],[],[gnu])
+
+AT_CLEANUP

tests/remfiles07.at

@@ -0,0 +1,63 @@
+# Process this file with autom4te to create testsuite. -*- Autotest -*-
+# Test suite for GNU tar.
+# Copyright 2013 Free Software Foundation, Inc.
+#
+# 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/>.
+
+# Description: See remfiles06.at
+# Reported by: Nathan Stratton Treadway <nathanst@ontko.com>
+# References: <20130924185129.GO32256@shire.ontko.com>
+
+AT_SETUP([incremental with -C to absolute path])
+AT_KEYWORDS([incremental create remove-files remfiles07])
+
+AT_TAR_CHECK([
+AT_SORT_PREREQ
+mkdir tartest
+cd tartest
+mkdir foo
+echo foo/file > foo/file
+mkdir bar
+echo bar/file > bar/file
+decho A
+find|sort
+
+DIR=`pwd`
+decho B
+tar -cvf ../foo.tar --remove-files -C foo file -C $DIR/bar file
+
+decho C
+find|sort
+],
+[0],
+[A
+.
+./bar
+./bar/file
+./foo
+./foo/file
+B
+file
+file
+C
+.
+./bar
+./foo
+],
+[A
+B
+C
+],[],[],[gnu])
+
+AT_CLEANUP

tests/testsuite.at

@@ -297,6 +297,7 @@ m4_include([incr04.at])
 m4_include([incr05.at])
 m4_include([incr06.at])
 m4_include([incr07.at])
+m4_include([incr08.at])
 
 AT_BANNER([Files removed while archiving])
 m4_include([filerem01.at])
@@ -377,6 +378,10 @@ AT_BANNER([Removing files after archiving])
 m4_include([remfiles01.at])
 m4_include([remfiles02.at])
 m4_include([remfiles03.at])
+m4_include([remfiles04.at])
+m4_include([remfiles05.at])
+m4_include([remfiles06.at])
+m4_include([remfiles07.at])
 
 AT_BANNER([Extended attributes])
 m4_include([xattr01.at])