GNU bug report logs - #17804
RFC: fixing the 32-bit size and time limits in gzip file format

Previous Next

Full log

View this message in rfc822 format

From: help-debbugs <at> gnu.org (GNU bug Tracking System)
To: Wolfgang Formann <wformann <at> arcor.de>
Subject: bug#30936: closed (Re: bug#17804: RFC: fixing the 32-bit size and
 time limits in gzip file format)
Date: Thu, 16 Dec 2021 02:34:02 +0000

[Message part 1 (text/plain, inline)]

Your bug report

#17804: gzip -l reports wrong size for decompressed files larger than 4GB

which was filed against the gzip package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to 30936 <at> debbugs.gnu.org.

-- 
17804: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=17804
GNU Bug Tracking System
Contact help-debbugs <at> gnu.org with problems

[Message part 2 (message/rfc822, inline)]

From: Paul Eggert <eggert <at> cs.ucla.edu>
To: Petr Stodůlka <pstodulk <at> redhat.com>
Cc: 17804-done <at> debbugs.gnu.org
Subject: Re: bug#17804: RFC: fixing the 32-bit size and time limits in gzip
 file format
Date: Wed, 15 Dec 2021 18:33:12 -0800

On 6/18/14 15:12, Paul Eggert wrote:
> One simple way forward would be to implement what pigz -tl does, namely, 
> decompress the input stream and discard the output, but print its size.

I finally got around to implementing that suggestion:

https://git.savannah.gnu.org/cgit/gzip.git/commit/?id=cf26200380585019e927fe3cf5c0ecb7c8b3ef14
https://git.savannah.gnu.org/cgit/gzip.git/commit/?id=32fef43b442c7abc70414863d64718cd06f6477a

So I am closing this old bug report.

[Message part 3 (message/rfc822, inline)]

From: Wolfgang Formann <wformann <at> arcor.de>
To: bug-gzip <at> gnu.org
Subject: gzip -l reports wrong size for decompressed files larger than 4GB
Date: Sun, 25 Mar 2018 11:15:46 +0200

Hello!

I am using gzip 1.6 from openSUSE Leap 42.3 with latest patches

$ file /usr/bin/gzip
/usr/bin/gzip: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked, interpreter 
/lib64/ld-linux-x86-64.so.2, for GNU/Linux 3.0.0, BuildID[sha1]=7103d56e17e6f81a52db927e393dce601c3af0e1, stripped

There is a compressed file available at https://data.dnb.de/opendata/GND.rdf.gz which has a size of 1.232.465.678 bytes. 
Uncompressed it will have a size of 19.465.374.298

The problem is:
$ gzip -l GND.rdf.gz
         compressed        uncompressed  ratio uncompressed_name
         1232465678          2285505114  46.1% GND.rdf

This number 2285505114 is actually the lower 32 bits of the real size 19GB.
$ echo "19465374298-16*1024*1024*1024" | bc
2285505114

Such a behaviour is okay for 32-bit software, 64-bit should show correct numbers.

Thanks
Wolfgang

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.