[Boost-bugs] [Boost C++ Libraries] #5584: gzip_decompressor sometimes truncates data

Subject: [Boost-bugs] [Boost C++ Libraries] #5584: gzip_decompressor sometimes truncates data
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2011-05-31 18:57:15

#5584: gzip_decompressor sometimes truncates data
------------------------------------------------+---------------------------
 Reporter:  Hans-Andreas Engel <engel@…>        |       Owner:         
     Type:  Bugs                                |      Status:  new    
Milestone:  To Be Determined                    |   Component:  None   
  Version:  Boost 1.41.0                        |    Severity:  Problem
 Keywords:                                      |  
------------------------------------------------+---------------------------
 Th following trivial sample program `boost_gunzip.cc` only decompresses
 files partially.  This issue only appears for a minority of the files.
 {{{
 #include <boost/iostreams/device/file.hpp>
 #include <boost/iostreams/filtering_stream.hpp>
 #include <boost/iostreams/filter/gzip.hpp>

 #include <iostream>
 #include <ios>

 int main(int argc, const char *argv[]) {
     if (argc != 2) {
         std::cerr << "need exactly one argument" << std::endl;
         return 1;
     }

     boost::iostreams::filtering_istream in;
     in.push(boost::iostreams::gzip_decompressor());
     in.push(boost::iostreams::file_source(argv[1],
       std::ios_base::in | std::ios_base::binary));

     while (in.good()) {
         char c = in.get();
         if (in.good()) std::cout << c;
     }
 };
 }}}

 In the following example, `gzip_decompressor` misses 113 bytes:
 {{{
 ~$ cat <(for i in `seq 0 100`; do echo 'Mon May 30 23:17:43 EDT 2011';
 done) > /tmp/a
 ~$ md5sum /tmp/a
 040fce9cef21c343fd9ab2aecf1515e3  /tmp/a
 ~$ wc -c /tmp/a
 2929 /tmp/a
 ~$ gzip /tmp/a
 ~$ md5sum /tmp/a.gz
 46bd5683f86075e30124c5a6a1d2f83d  /tmp/a.gz

 ~$ zcat /tmp/a.gz | wc -c
 2929
 ~$ ./boost_gunzip /tmp/a.gz | wc -c
 2816
 }}}

 This is on a RHEL 6.1 64bit system, i.e., using `boost-
 iostreams-1.41.0-11.el6.x86_64`.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/5584>
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