#240: Unhandled Z_BUF_ERROR inflating compressed stream

#240: Unhandled Z_BUF_ERROR inflating compressed stream
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 Reporter:  steven    |       Owner:
     Type:  defect    |      Status:  new
 Priority:  normal    |   Milestone:  1.5.0
Component:  protocol  |     Version:  1.4.1
 Keywords:            |  Blocked By:
   Blocks:            |
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 When using libssh2 to perform an SFTP file transfer from the "JSCAPE MFT
 Server" (http://www.jscape.com) the transfer failed. The default JSCAPE
 configuration is to enforce zlib compression on SSH2 sessions so the
 session was compressed. The relevant part of the debug trace contained:
 {{{
  [libssh2] 1.052750 Transport: unhandled zlib error -5
  [libssh2] 1.052750 Failure Event: -29 - decompression failure
 }}}
 The trace comes from comp_method_zlib_decomp() in comp.c. The "unhandled
 zlib error -5" is the status returned from the zlib function inflate().
 The -5 status corresponds to "Z_BUF_ERROR".

 The inflate() function takes a pointer to a z_stream structure and
 "inflates" (decompresses) as much as it can. The relevant fields of the
 z_stream structure are:
 * next_in - pointer to the input buffer containing compressed data
 * avail_in - the number of bytes available at next_in
 * next_out - pointer to the output buffer to be filled with uncompressed
 data
 * avail_out - how much space available at next_out
 So, to decompress data you set up a z_stream struct with the relevant