ls --color: Don't stat symlinks when neither ORPHAN nor MISSING attribute has a color.

* src/ls.c (main): Don't set check_symlink_color when C_EXEC is
colored, unless ln=target (aka color_symlink_as_referent) is set.
(gobble_file): Set f->linkok = true also when !check_symlink_color.
http://thread.gmane.org/gmane.comp.gnu.coreutils.bugs/10608/focus=10927
Reported by Jeremy Maitin-Shepard.
* tests/strace: New file, contents extracted from...
* tests/mv/atomic: ...here.  Source strace.
* tests/ls/stat-free-symlinks: New file.  Test for the above.
Use strace to ensure that in this corner case, ls does not call stat.
* tests/ls/Makefile.am (TESTS): Add stat-free-symlinks.
* tests/Makefile.am (EXTRA_DIST): Add strace.

1 files changed, 30 insertions, 0 deletions

diff --git a/tests/strace b/tests/strace
new file mode 100644
index 000000000..0bb022ac9
--- /dev/null
+++ b/tests/strace
@@ -0,0 +1,30 @@
+# Skip the current test if strace is not available or doesn't work.
+
+# Copyright (C) 2007 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 of the License, 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, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+# 02110-1301, USA.
+
+strace -V < /dev/null > /dev/null 2>&1 ||
+{
+  echo "$0: no strace program, so skipping this test" 1>&2
+  (exit 77); exit 77
+}
+
+strace -qe unlink echo > /dev/null 2>&1 ||
+{
+  echo "$0: strace doesn't work, so skipping this test" 1>&2
+  (exit 77); exit 77
+}