[Boost-bugs] [Boost C++ Libraries] #5291: bzip2_decompressor does not work properly with a filtering_streambuf

Subject: [Boost-bugs] [Boost C++ Libraries] #5291: bzip2_decompressor does not work properly with a filtering_streambuf
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2011-03-11 15:12:04

#5291: bzip2_decompressor does not work properly with a filtering_streambuf
--------------------------------------------------------+-------------------
 Reporter:  Chris Steenwyk <chris.steenwyk@…>           |       Owner:  turkanis 
     Type:  Bugs                                        |      Status:  new      
Milestone:  To Be Determined                            |   Component:  iostreams
  Version:  Boost 1.45.0                                |    Severity:  Problem  
 Keywords:                                              |  
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 The revision 63057 of boost/iostreams/filter/bzip2.hpp seems to have
 broken the ability to use the bzip2 decompressor in a filtering streambuf.
 When I pass a stream into the buffer it throws data_error_magic. Stepping
 through the code I can see it correctly decode the zipped data, but then
 it continues to attempt to decode data even after eof is reached.

 Looking at the changes to bzip2_decompressor_impl I see the following
 issues:
 1.) The function returns true even if _eof is set to true.  This causes
 the "done" flag in the "Read" function in symmetric.hpp to be set to
 false, which causes the bzip2_decompressor_impl function to execute again,
 after EOL.
 2.) On the second execution when _eof is set, the "close" function resets
 _eof to  false, which can cause the function to throw the exception.

 In the specific instance I am using, my bzip compressed section is
 embedded in the middle of the stream, so src_begin won't equal src_end.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/5291>
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