Re: [Boost-bugs] [Boost C++ Libraries] #5237: filtering_ostream produce incorrect empty files with gzip_compressor and other filters

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #5237: filtering_ostream produce incorrect empty files with gzip_compressor and other filters
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2012-01-06 20:24:41

#5237: filtering_ostream produce incorrect empty files with gzip_compressor and
other filters
-----------------------------------+----------------------------------------
  Reporter:  come.raczy@…          |       Owner:  turkanis 
      Type:  Bugs                  |      Status:  new      
 Milestone:  To Be Determined      |   Component:  iostreams
   Version:  Boost 1.44.0          |    Severity:  Problem  
Resolution:                        |    Keywords:           
-----------------------------------+----------------------------------------

Comment (by Davin):

 Same issue in 1.47.0 and 1.48.0.

 You can patch boost/iostreams/filter/gzip.hpp, at line 251, insert the
 following two lines:

 {{{
 if (!(flags_ & f_header_done))
   write(snk, 0, 0);
 }}}

 If nothing has been written, calling write with no content will generate a
 proper empty gzip file.  This is preferable to having a zero-length file
 for two reasons.  First, it is consistent with the bzip2 filter to create
 a proper empty compressed file rather than a zero-length file.  Second,
 zcat won't subsequently barf with a "unexpected end of file" error.

 Hope it helps.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/5237#comment:2>
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