Bug 482903

Looks like the new rpm 4.4.2.3-9.el5 package brings this bug to RHEL 5.3.  This is proving to be quite serious.

+++ This bug was initially created as a clone of Bug #304121 +++

Description of problem:
When a the source directory for a file ends with a '/', debugedit can spit out a
"canonicalization unexpectedly shrank by one character" error and fail.  That's
not really enough for most people to figure out what's gone wrong or how to fix it.

Version-Release number of selected component (if applicable):
rpm-build-4.4.2.2-0.5.rc2

How reproducible:
Always

Steps to Reproduce:
1. mkdir src
2. cat > src/foo.c <<- EOF
   int
   main(int argc, char **argv)
   {
        return 0;
   }
EOF
3. cd src
4. gcc -g3 -o foo ../src//foo.c
5. /usr/lib/rpm/debugedit -b `pwd` -d / foo
  
Actual results:
/usr/lib/rpm/debugedit: canonicalization unexpectedly shrank by one character

Expected results:
Either not fail, or indicate that a directory name in the table ended with a
'/', which it probably shouldn't have contained.

Additional info:
I actually ran into this with openafs 1.4.4, but I'm including a smaller
reproducer which I think triggers the same bug.

--- Additional comment from pmatilai on 2007-09-27 04:49:46 EDT ---

Hmm, it's not the trailing '/' that troubles debugedit per se but the fact that
the canonicalized path is exactly one character shorter than the original which
is a case that it can't (and can't be made to AFAICT) handle. Roland, care to
comment?

The error message could certainly be clearer on what sort of problem to look for
(basically single extra '/' somewhere in the path).

--- Additional comment from roland on 2007-09-27 19:26:18 EDT ---

Indeed, the format makes it impossible to do rewriting in place unless the table
shrinks by at least 2 or not at all (it's beyond the scope of debugedit to
resize things).  For cases in the directory table you could do an ugly kludge by
repeating the leading / or adding a trailing one to preserve the size.  But
there is no trick like that to do in the file table, where any leading or
trailing slash would change the final file name so it doesn't work (not just is
wrongly ugly).  The !=-1 size restriction is for the whole table cumulatively,
so with extra slashes removed by canonicalization, it is only a problem when
there is only one such file name.  It could do a kludge of adding a trailing
slash to some dir table entry when this arises, which would work and only uglify
some of the names to /foo//bar.  Still, I suspect packagers will be OK with it
being an error they have to fix or work around, if they can tell what to do.

The error message you get now is certainly pretty arcane.  The other error of
the same ilk has a better message.  

Looking at canonicalize_path, I think it is true that a doubled / is the only
way it could shrink by exactly one.  But I could use a second set of eyes to
verify there really is no obscure innocent case that could do that.  If that's
true, then we can simply change the error message to identify this problem.

--- Additional comment from jan.iven on 2007-11-14 05:53:44 EDT ---

FYI, the instance that triggers this bug has apparently been "fixed" in the
Fedora-8-specific OpenAFS SRPM at
http://openafs.org/dl/openafs/1.4.5/fedora-8/SRPMS/openafs-1.4.5-fc8.2.src.rpm
Nonetheless, this could of course affect other packages as well..


--- Additional comment from tibbs.edu on 2007-12-06 18:43:46 EDT ---

Just a note that a koji build for syslog-ng failed with the same error:
http://koji.fedoraproject.org/koji/taskinfo?taskID=265344

I'm not sure what would have changed to cause this package to stop building in
this manner.

--- Additional comment from roland on 2007-12-06 20:21:12 EDT ---

This line from the log suggests the problem:

/home/bazsi/zwa/git//syslog-ng/syslog-ng--mainline--2.0/src/cfg-lex.l:247:
warning: ignoring return value of 'fwrite', declared with attribute
warn_unused_result

The common reason for this error is // instead of / inside a file name.
This arises from using a trailing / on a directory name in a macro or makefile
variable usually.  

It may be a further problem that this absolute directory name appears in the
build.  Presumably it is in # line file name strings in cfg-lex.c, which is
generated from cfg-lex.l.  If this file is included in the upstream tarball like
this, then so it is and that is fine from the rpm-reproducible-builds
perspective.  Even so, upstream should be taught how to generate genericized
file names for their dist tarballs, so it winds up just # line "cfg-lex.l" or
suchlike.  If the rpm build is running lex/flex to generate cfg-lex.c itself,
then it's just our spec file that has to be fixed.

--- Additional comment from silfreed on 2008-01-08 11:51:04 EDT ---

I've created a patch for syslog-ng that fixes the double slash in the 
cfg-lex.c and cfg-grammar.c files but I still get the error with debuginfo and 
the warning referenced above as well.

I'm sorry I'm not much more help with this; I still don't fully understand 
what the error is here.

--- Additional comment from fedora-triage-list on 2008-05-13 23:16:33 EDT ---

Changing version to '9' as part of upcoming Fedora 9 GA.
More information and reason for this action is here:
http://fedoraproject.org/wiki/BugZappers/HouseKeeping

--- Additional comment from orion.com on 2008-05-27 13:40:58 EDT ---

I'm seeing the same problem, but don't see any '//' occurrences.  See
http://koji.fedoraproject.org/koji/getfile?taskID=630760&name=build.log

If anyone has any suggestions as to how to fix, I would appreciate it.

--- Additional comment from roland on 2008-05-27 17:30:17 EDT ---

Since that was a scratch build, I do not have the sources from pkgs cvs to
reproduce your build problem.

--- Additional comment from orion.com on 2008-05-27 17:36:54 EDT ---

http://www.cora.nwra.com/~orion/fedora/gridengine-6.2-0.beta.1.fc10.src.rpm

--- Additional comment from roland on 2008-05-27 18:45:27 EDT ---

source/clients/qmon/qmon_cplx.c: 61: #include "spool/flatfile//sge_flatfile_obj.h"
source/libs/spool/flatfile/test_sge_spooling_flatfile.c: 47: #include
"spool/flatfile//sge_flatfile.h"
source/libs/spool/flatfile/test_sge_spooling_flatfile.c: 50: #include
"spool/flatfile//sge_flatfile_obj.h"


--- Additional comment from orion.com on 2008-05-28 11:10:22 EDT ---

Thanks, didn't think to check for includes inside the source files.