coreutils readlink 5.2.1 with DVL patch seems to work properly

[Thomas Hood]

In April Dmitry V. Levin mentioned[1] that he was making available[2]
a patch for the readlink program in coreutils 5.2.1 that implements
the behavior we have discussed.

1] http://lists.gnu.org/archive/html/bug-coreutils/2004-04/msg00036.html
2] ftp://ftp.altlinux.org/pub/people/ldv/coreutils/

I tested DVL's patch quickly today and found that it works properly.

coreutils-5.2.1.dmitry readlink -e  =  coreutils-5.0.91 readlink -f
coreutils-5.2.1.dmitry readlink -f  =  sysvinit-2.85-18 readlink -f
coreutils-5.2.1.dmitry readlink -m  =  sysvinit-2.85-18 readlink -ff
except that the former never returns nonzero whereas the latter does
(which is good).

Here are the details of my tests.  I downloaded coreutils 5.21 from
a GNU mirror and applied DVL's patch to it.  I build it on a sid
system.

Then I created a directory /tmp/oo with four symlinks in it:

    yestarg -> targ
    notarg -> xyzzy
    notarg_nodir -> xyzzy/xyzzy
    notarg_yesdir -> subdir/xyzzy

plus the file:

    targ

and the directory:

    subdir

I ran the following script:

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#!/bin/sh
test()
{
        OPT="$1"
        for ARG in nosuch yestarg notarg notarg_yesdir notarg_nodir ; do
                echo "$R -$OPT $ARG:"
                $R -$OPT $ARG && echo OK || echo fail
                echo
        done
        echo "------------------------------"
        echo
}
R=/bin/readlink
test f
R=/lib/init/readlink
test f
test ff
R=/usr/src/coreutils-5.2.1/src/readlink
test e
test f
test m
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

and it generated the following output.  Note that /bin/readlink
is the readlink that currently ships with Debian: it is from
coreutils 5.0.91-2.   /usr/src/coreutils-5.2.1 is the directory
where I built the DVL-patched readlink program.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/bin/readlink -f nosuch:
fail

/bin/readlink -f yestarg:
/tmp/oo/targ
OK

/bin/readlink -f notarg:
fail

/bin/readlink -f notarg_yesdir:
fail

/bin/readlink -f notarg_nodir:
fail

------------------------------

/lib/init/readlink -f nosuch:
/tmp/oo/nosuch
OK

/lib/init/readlink -f yestarg:
/tmp/oo/targ
OK

/lib/init/readlink -f notarg:
/tmp/oo/xyzzy
OK

/lib/init/readlink -f notarg_yesdir:
/tmp/oo/subdir/xyzzy
OK

/lib/init/readlink -f notarg_nodir:
fail

------------------------------

/lib/init/readlink -ff nosuch:
/tmp/oo/nosuch
OK

/lib/init/readlink -ff yestarg:
/tmp/oo/targ
OK

/lib/init/readlink -ff notarg:
/tmp/oo/xyzzy
OK

/lib/init/readlink -ff notarg_yesdir:
/tmp/oo/subdir/xyzzy
OK

/lib/init/readlink -ff notarg_nodir:
/tmp/oo/xyzzy/xyzzy
fail

------------------------------

/usr/src/coreutils-5.2.1/src/readlink -e nosuch:
fail

/usr/src/coreutils-5.2.1/src/readlink -e yestarg:
/tmp/oo/targ
OK

/usr/src/coreutils-5.2.1/src/readlink -e notarg:
fail

/usr/src/coreutils-5.2.1/src/readlink -e notarg_yesdir:
fail

/usr/src/coreutils-5.2.1/src/readlink -e notarg_nodir:
fail

------------------------------

/usr/src/coreutils-5.2.1/src/readlink -f nosuch:
/tmp/oo/nosuch
OK

/usr/src/coreutils-5.2.1/src/readlink -f yestarg:
/tmp/oo/targ
OK

/usr/src/coreutils-5.2.1/src/readlink -f notarg:
/tmp/oo/xyzzy
OK

/usr/src/coreutils-5.2.1/src/readlink -f notarg_yesdir:
/tmp/oo/subdir/xyzzy
OK

/usr/src/coreutils-5.2.1/src/readlink -f notarg_nodir:
fail

------------------------------

/usr/src/coreutils-5.2.1/src/readlink -m nosuch:
/tmp/oo/nosuch
OK

/usr/src/coreutils-5.2.1/src/readlink -m yestarg:
/tmp/oo/targ
OK

/usr/src/coreutils-5.2.1/src/readlink -m notarg:
/tmp/oo/xyzzy
OK

/usr/src/coreutils-5.2.1/src/readlink -m notarg_yesdir:
/tmp/oo/subdir/xyzzy
OK

/usr/src/coreutils-5.2.1/src/readlink -m notarg_nodir:
/tmp/oo/xyzzy/xyzzy
OK

------------------------------
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~