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Diffstat (limited to 'contrib/epee/include/gzip_encoding.h')
| -rw-r--r-- | contrib/epee/include/gzip_encoding.h | 227 |
1 files changed, 227 insertions, 0 deletions
diff --git a/contrib/epee/include/gzip_encoding.h b/contrib/epee/include/gzip_encoding.h new file mode 100644 index 000000000..2be51e77d --- /dev/null +++ b/contrib/epee/include/gzip_encoding.h @@ -0,0 +1,227 @@ +// Copyright (c) 2006-2013, Andrey N. Sabelnikov, www.sabelnikov.net +// All rights reserved. +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are met: +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above copyright +// notice, this list of conditions and the following disclaimer in the +// documentation and/or other materials provided with the distribution. +// * Neither the name of the Andrey N. Sabelnikov nor the +// names of its contributors may be used to endorse or promote products +// derived from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND +// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED +// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE +// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER BE LIABLE FOR ANY +// DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES +// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; +// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND +// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS +// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +// + + + + +#ifndef _GZIP_ENCODING_H_ +#define _GZIP_ENCODING_H_ +#include "net/http_client_base.h" +#include "zlib/zlib.h" +//#include "http.h" + + +namespace epee +{ +namespace net_utils +{ + + + + class content_encoding_gzip: public i_sub_handler + { + public: + /*! \brief + * Function content_encoding_gzip : Constructor + * + */ + inline + content_encoding_gzip(i_target_handler* powner_filter, bool is_deflate_mode = false):m_powner_filter(powner_filter), + m_is_stream_ended(false), + m_is_deflate_mode(is_deflate_mode), + m_is_first_update_in(true) + { + memset(&m_zstream_in, 0, sizeof(m_zstream_in)); + memset(&m_zstream_out, 0, sizeof(m_zstream_out)); + int ret = 0; + if(is_deflate_mode) + { + ret = inflateInit(&m_zstream_in); + ret = deflateInit(&m_zstream_out, Z_DEFAULT_COMPRESSION); + }else + { + ret = inflateInit2(&m_zstream_in, 0x1F); + ret = deflateInit2(&m_zstream_out, Z_DEFAULT_COMPRESSION, Z_DEFLATED, 0x1F, 8, Z_DEFAULT_STRATEGY); + } + } + /*! \brief + * Function content_encoding_gzip : Destructor + * + */ + inline + ~content_encoding_gzip() + { + inflateEnd(& m_zstream_in ); + deflateEnd(& m_zstream_out ); + } + /*! \brief + * Function update_in : Entry point for income data + * + */ + inline + virtual bool update_in( std::string& piece_of_transfer) + { + + bool is_first_time_here = m_is_first_update_in; + m_is_first_update_in = false; + + if(m_pre_decode.size()) + m_pre_decode += piece_of_transfer; + else + m_pre_decode.swap(piece_of_transfer); + piece_of_transfer.clear(); + + std::string decode_summary_buff; + + size_t ungzip_size = m_pre_decode.size() * 0x30; + std::string current_decode_buff(ungzip_size, 'X'); + + //Here the cycle is introduced where we unpack the buffer, the cycle is required + //because of the case where if after unpacking the data will exceed the awaited size, we will not halt with error + bool continue_unpacking = true; + bool first_step = true; + while(m_pre_decode.size() && continue_unpacking) + { + + //fill buffers + m_zstream_in.next_in = (Bytef*)m_pre_decode.data(); + m_zstream_in.avail_in = (uInt)m_pre_decode.size(); + m_zstream_in.next_out = (Bytef*)current_decode_buff.data(); + m_zstream_in.avail_out = (uInt)ungzip_size; + + int flag = Z_SYNC_FLUSH; + int ret = inflate(&m_zstream_in, flag); + CHECK_AND_ASSERT_MES(ret>=0 || m_zstream_in.avail_out ||m_is_deflate_mode, false, "content_encoding_gzip::update_in() Failed to inflate. err = " << ret); + + if(Z_STREAM_END == ret) + m_is_stream_ended = true; + else if(Z_DATA_ERROR == ret && is_first_time_here && m_is_deflate_mode&& first_step) + { + // some servers (notably Apache with mod_deflate) don't generate zlib headers + // insert a dummy header and try again + static char dummy_head[2] = + { + 0x8 + 0x7 * 0x10, + (((0x8 + 0x7 * 0x10) * 0x100 + 30) / 31 * 31) & 0xFF, + }; + inflateReset(&m_zstream_in); + m_zstream_in.next_in = (Bytef*) dummy_head; + m_zstream_in.avail_in = sizeof(dummy_head); + + ret = inflate(&m_zstream_in, Z_NO_FLUSH); + if (ret != Z_OK) + { + LOCAL_ASSERT(0); + m_pre_decode.swap(piece_of_transfer); + return false; + } + m_zstream_in.next_in = (Bytef*)m_pre_decode.data(); + m_zstream_in.avail_in = (uInt)m_pre_decode.size(); + + ret = inflate(&m_zstream_in, Z_NO_FLUSH); + if (ret != Z_OK) + { + LOCAL_ASSERT(0); + m_pre_decode.swap(piece_of_transfer); + return false; + } + } + + + //leave only unpacked part in the output buffer to start with it the next time + m_pre_decode.erase(0, m_pre_decode.size()-m_zstream_in.avail_in); + //if decoder gave nothing to return, then everything is ahead, now simply break + if(ungzip_size == m_zstream_in.avail_out) + break; + + //decode_buff currently stores data parts that were unpacked, fix this size + current_decode_buff.resize(ungzip_size - m_zstream_in.avail_out); + if(decode_summary_buff.size()) + decode_summary_buff += current_decode_buff; + else + current_decode_buff.swap(decode_summary_buff); + + current_decode_buff.resize(ungzip_size); + first_step = false; + } + + //Process these data if required + bool res = true; + + res = m_powner_filter->handle_target_data(decode_summary_buff); + + return true; + + } + /*! \brief + * Function stop : Entry point for stop signal and flushing cached data buffer. + * + */ + inline + virtual void stop(std::string& OUT collect_remains) + { + } + protected: + private: + /*! \brief + * Pointer to parent HTTP-parser + */ + i_target_handler* m_powner_filter; + /*! \brief + * ZLIB object for income stream + */ + z_stream m_zstream_in; + /*! \brief + * ZLIB object for outcome stream + */ + z_stream m_zstream_out; + /*! \brief + * Data that could not be unpacked immediately, left to wait for the next packet of data + */ + std::string m_pre_decode; + /*! \brief + * The data are accumulated for a package in the buffer to send the web client + */ + std::string m_pre_encode; + /*! \brief + * Signals that stream looks like ended + */ + bool m_is_stream_ended; + /*! \brief + * If this flag is set, income data is in HTTP-deflate mode + */ + bool m_is_deflate_mode; + /*! \brief + * Marks that it is a first data packet + */ + bool m_is_first_update_in; + }; +} +} + + + +#endif //_GZIP_ENCODING_H_ |