[Boost-bugs] [Boost C++ Libraries] #6994: gzip_decompressor issue with unusual files

Subject: [Boost-bugs] [Boost C++ Libraries] #6994: gzip_decompressor issue with unusual files
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2012-06-18 08:48:13

#6994: gzip_decompressor issue with unusual files
---------------------------------------------------+------------------------
 Reporter:  Gavin Band <gavinband@…>               |       Owner:  turkanis 
     Type:  Bugs                                   |      Status:  new      
Milestone:  To Be Determined                       |   Component:  iostreams
  Version:  Boost 1.49.0                           |    Severity:  Problem  
 Keywords:  gzip gzip_decompressor                 |  
---------------------------------------------------+------------------------
 The gzip_decompressor implementation fails on gzip files that contain an
 empty block after a non-empty one.  (You can make such a file by gzipping
 a nonempty and an empty file and concatenating them, but they are also
 sometimes written by other tools.)  Here such a file:

 $ hexdump -C hello.txt.gz
 00000000  1f 8b 08 00 0d ea b4 4f  00 03 cb 48 cd c9 c9 57
 |.......O...H...W|
 00000010  28 c9 48 2d 4a e5 02 00  8e 45 d1 59 0c 00 00 00
 |(.H-J....E.Y....|
 00000020  1f 8b 08 00 18 ea b4 4f  00 03 03 00 00 00 00 00
 |.......O........|
 00000030  00 00 00 00                                       |....|
 00000034

 My file reading code is:

 /* test.cpp */
 #include <iostream>
 #include <boost/iostreams/filtering_stream.hpp>
 #include <boost/iostreams/filter/gzip.hpp>
 #include <boost/iostreams/copy.hpp>
 #include <boost/iostreams/device/file.hpp>

 int main( int, char** ) {
         boost::iostreams::filtering_istream stream ;
         stream.push( boost::iostreams::gzip_decompressor() ) ;
         boost::iostreams::file_source file( argv[1] ) ;
         stream.push( file ) ;
         boost::iostreams::copy( stream, std::cout ) ;
 }

 Using gunzip on the above file works fine:
 $ gunzip -c ../hello.txt.bgz
 Hello, this is a test file.

 Using the test program does not:
 $ ./test  ../hello.txt.bgz
 terminate called after throwing an instance of
 'boost::exception_detail::clone_impl<boost::exception_detail::error_info_injector<boost::iostreams::gzip_error>
 >'
   what():  gzip error

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/6994>
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