Re: [PATCH] ls: with -LR, exit with status 2 upon detecting a cycle

[Jim Meyering]

Jim Meyering wrote:
> Here's a fix to make ls -LR work the same way Solaris 10's /bin/ls
> does in the presence of a cycle.

I've tweaked the patch to udpate the documentation, too.

>From 9fad0c69f218a57c9404f7c1137961eec5a818f1 Mon Sep 17 00:00:00 2001
From: Jim Meyering <address@hidden>
Date: Mon, 28 Sep 2009 18:29:02 +0200
Subject: [PATCH] ls: with -LR, exit with status 2 upon detecting a cycle

* src/ls.c (print_dir): Diagnosing the cycle is not enough.
Also set exit status to 2.  This is what Solaris' /bin/ls does, too.
* tests/ls/infloop: Rework test: match both expected stdout and stderr.
Require an exit status of 2 in this case.
* doc/coreutils.texi (ls invocation): Mention that a loop provokes
in an exit status of 2.
* NEWS (Bug fixes): Mention it.
Reported by Yang Ren in http://bugzilla.redhat.com/525402.
---
 NEWS               |    2 ++
 doc/coreutils.texi |    5 +++--
 src/ls.c           |    1 +
 tests/ls/infloop   |   25 +++++++++++++------------
 4 files changed, 19 insertions(+), 14 deletions(-)

diff --git a/NEWS b/NEWS
index 5060502..d0a9a7d 100644
--- a/NEWS
+++ b/NEWS
@@ -16,6 +16,8 @@ GNU coreutils NEWS                                    -*- 
outline -*-
   when the color of a more specific type is disabled.
   [bug introduced in coreutils-5.90]

+  ls -LR exits with status 2, not 0, when it encounters a cycle
+
 ** Portability

   On Solaris 9, many commands would mistakenly treat file/ the same as
diff --git a/doc/coreutils.texi b/doc/coreutils.texi
index b10cc10..5026e76 100644
--- a/doc/coreutils.texi
+++ b/doc/coreutils.texi
@@ -6113,8 +6113,9 @@ ls invocation
 1 minor problems  (e.g., failure to access a file or directory not
   specified as a command line argument.  This happens when listing a
   directory in which entries are actively being removed or renamed.)
-2 serious trouble (e.g., memory exhausted, invalid option or failure
-  to access file or directory specified as a command line argument)
+2 serious trouble (e.g., memory exhausted, invalid option, failure
+  to access a file or directory specified as a command line argument
+  or a directory loop)
 @end display

 Also see @ref{Common options}.
diff --git a/src/ls.c b/src/ls.c
index 1bb6873..86f5c32 100644
--- a/src/ls.c
+++ b/src/ls.c
@@ -2471,6 +2471,7 @@ print_dir (char const *name, char const *realname, bool 
command_line_arg)
           error (0, 0, _("%s: not listing already-listed directory"),
                  quotearg_colon (name));
           closedir (dirp);
+          set_exit_status (true);
           return;
         }

diff --git a/tests/ls/infloop b/tests/ls/infloop
index 419d7a9..b77f88c 100755
--- a/tests/ls/infloop
+++ b/tests/ls/infloop
@@ -1,7 +1,7 @@
 #!/bin/sh
 # show that the following no longer makes ls infloop
 # mkdir loop; cd loop; ln -s ../loop sub; ls -RL
-
+# Also ensure ls exits with status = 2 in that case.
 # Copyright (C) 2001-2002, 2004, 2006-2009 Free Software Foundation, Inc.

 # This program is free software: you can redistribute it and/or modify
@@ -27,21 +27,22 @@ fi
 mkdir loop || framework_failure
 ln -s ../loop loop/sub || framework_failure

-fail=0
-
-ls -RL loop 2>err | head -n 7 > out
-# With an inf-looping ls, out will contain these 7 lines:
-cat <<EOF > bad
+cat <<\EOF > exp-out || framework_failure
 loop:
 sub
+EOF

-loop/sub:
-sub
-
-loop/sub/sub:
+cat <<\EOF > exp-err || framework_failure
+ls: loop/sub: not listing already-listed directory
 EOF

-# Make sure we don't get the "bad" output.
-compare out bad > /dev/null 2>&1 && fail=1
+fail=0
+
+timeout 1 ls -RL loop 2>err > out
+# Ensure that ls exits with status 2 upon detecting a cycle
+test $? = 2 || fail=1
+
+compare err exp-err || fail=1
+compare out exp-out || fail=1

 Exit $fail
--
1.6.5.rc2.177.ga9dd6