Optimize searches for directory structures by keeping a pointer to struct directory in struct name.

* src/common.h (struct name): New member `directory' replaces
dir_contents. Rearrange members.
(rebase_directory): Change signature.
(scan_directory): Change signature.
(name_fill_directory)
(directory_contents, safe_directory_contents): New prototypes.
(append_incremental_renames): Change signature.
(replace_prefix): New proto.
* src/compare.c (diff_dumpdir): Use directory_contents + scan_directory.
* src/create.c
* src/incremen.c (replace_prefix): Move to misc.c
(rebase_directory): Rewrite.
(scan_directory): Return pointer to struct directory.
(directory_contents, safe_directory_contents): New functions.
(get_directory_contents): Remove.
(name_fill_directory): New function.
(append_incremental_renames): Rewrite. This also fixes a memory leak.
* src/names.c (name_gather, addname): Reflect changes in struct name.
(add_hierarchy_to_namelist): Rewrite using name_fill_directory and
directory_contents.
(rebase_child_list): Update call to rebase_directory.
(collect_and_sort_names): Optimize

* src/misc.c (replace_prefix): New function.
* src/names.c (add_hierarchy_to_namelist): Use new get_directory_contents.

* tests/incr05.at: New test case.
* tests/incr06.at: New test case.
* tests/Makefile.am, test/testsuite.at: Add incr05.at and incr06.at.

* doc/Makefile.am (check-options): Improve rule.
* doc/tar.texi, NEWS: Update.

tests/Makefile.am

@@ -76,6 +76,8 @@ TESTSUITE_AT = \
  incr02.at\
  incr03.at\
  incr04.at\
+ incr05.at\
+ incr06.at\
  indexfile.at\
  ignfail.at\
  link01.at\

tests/incr05.at

@@ -0,0 +1,49 @@
+# Process this file with autom4te to create testsuite. -*- Autotest -*-
+
+# Test suite for GNU tar.
+# Copyright (C) 2009 Free Software Foundation, Inc.
+
+# 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 3, or (at your option)
+# any later version.
+
+# This program 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([incremental dumps with -C])
+AT_KEYWORDS([incremental incr05])
+
+AT_TAR_CHECK([
+mkdir dir
+mkdir dir/sub
+genfile --file dir/file1
+genfile --file dir/sub/file2
+
+dbfile=`pwd`/db
+
+echo Level 0
+tar -c -f archive.tar -g $dbfile -C dir -v --warning=no-new-dir .
+
+genfile --file dir/file3
+echo Level 1
+tar -c -f archive.tar -g $dbfile -C dir -v --warning=no-new-dir .
+],
+[0],
+[Level 0
+./
+./sub/
+./file1
+./sub/file2
+Level 1
+./
+./sub/
+./file3
+],[],[],[],[gnu, oldgnu, posix])
+
+AT_CLEANUP

tests/incr06.at

@@ -0,0 +1,81 @@
+# Process this file with autom4te to create testsuite. -*- Autotest -*-
+
+# Test suite for GNU tar.
+# Copyright (C) 2009 Free Software Foundation, Inc.
+
+# 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 3, or (at your option)
+# any later version.
+
+# This program 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([incremental dumps of nested directories])
+AT_KEYWORDS([incremental incr06])
+
+AT_TAR_CHECK([
+mkdir dir
+mkdir dir/sub
+mkdir dir/sub/a
+mkdir dir/sub/b
+genfile --file dir/file1
+genfile --file dir/sub/file2
+genfile --file dir/sub/a/file3
+
+dbfile=`pwd`/db
+
+echo Level 0 . sub
+tar -c -f archive-0.1.tar -g $dbfile.1 -C dir -v --warning=no-new-dir . sub
+echo Level 0 sub .
+tar -c -f archive-0.2.tar -g $dbfile.2 -C dir -v --warning=no-new-dir sub .
+
+mkdir dir/c
+genfile --file dir/sub/b/file4
+
+echo Level 1 . sub
+tar -c -f archive-1.1.tar -g $dbfile.1 -C dir -v --warning=no-new-dir . sub
+echo Level 1 sub .
+tar -c -f archive-1.2.tar -g $dbfile.2 -C dir -v --warning=no-new-dir sub .
+],
+[0],
+[Level 0 . sub
+./
+sub/
+sub/a/
+sub/b/
+./file1
+sub/file2
+sub/a/file3
+Level 0 sub .
+./
+sub/
+sub/a/
+sub/b/
+./file1
+sub/file2
+sub/a/file3
+Level 1 . sub
+./
+./c/
+sub/
+sub/a/
+sub/b/
+sub/b/file4
+Level 1 sub .
+./
+./c/
+sub/
+sub/a/
+sub/b/
+sub/b/file4
+],[],[],[],[gnu, oldgnu, posix])
+
+AT_CLEANUP
+
+

tests/testsuite.at

@@ -152,6 +152,8 @@ m4_include([listed01.at])
 m4_include([listed02.at])
 m4_include([incr03.at])
 m4_include([incr04.at])
+m4_include([incr05.at])
+m4_include([incr06.at])
 m4_include([rename01.at])
 m4_include([rename02.at])
 m4_include([rename03.at])