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103 lines
2.7 KiB
HTML
Executable File
103 lines
2.7 KiB
HTML
Executable File
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
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<HTML>
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<HEAD>
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<LINK REL="stylesheet" HREF="../../../../boost.css">
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<LINK REL="stylesheet" HREF="../theme/iostreams.css">
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<STYLE>
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PRE { background-color: white; border:0; font-size: 10pt }
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</STYLE>
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<TITLE>Zlib Example Output</TITLE>
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</HEAD>
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<BODY>
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<PRE>
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**** Length of code ****
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883
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**** Length of compressed code ****
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458
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**** Code before compression ****
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class zlib_compressor : public one_step_output_filter {
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public:
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explicit zlib_compressor(int level = Z_DEFAULT_COMPRESSION)
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: level_(level)
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{
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assert( level_ >= 0 && level_ <= 9 ||
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level == Z_DEFAULT_COMPRESSION );
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}
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protected:
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void do_filter(const vector_type& src, vector_type& dest)
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{
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dest.assign(src.begin(), src.end());
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dest.insert(dest.end(), (size_t) ceil(src.size() * 1.001) + 12, 0);
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unsigned long length = (unsigned long) dest.size();
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int result =
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compress2( (Bytef*) &dest[0], &length,
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(Bytef*) &src[0], (unsigned long) src.size(),
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level_ );
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if (result == Z_OK)
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dest.erase(dest.begin() + length, dest.end());
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else if (result == Z_MEM_ERROR)
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throw std::bad_alloc();
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else if (result == Z_STREAM_ERROR)
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throw std::ios_base::failure("invalid level");
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}
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private:
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int level_;
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};
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**** Code after decompression ****
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class zlib_compressor : public one_step_output_filter {
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public:
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explicit zlib_compressor(int level = Z_DEFAULT_COMPRESSION)
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: level_(level)
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{
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assert( level_ >= 0 && level_ <= 9 ||
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level == Z_DEFAULT_COMPRESSION );
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}
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protected:
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void do_filter(const vector_type& src, vector_type& dest)
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{
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dest.assign(src.begin(), src.end());
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dest.insert(dest.end(), (size_t) ceil(src.size() * 1.001) + 12, 0);
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unsigned long length = (unsigned long) dest.size();
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int result =
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compress2( (Bytef*) &dest[0], &length,
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(Bytef*) &src[0], (unsigned long) src.size(),
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level_ );
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if (result == Z_OK)
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dest.erase(dest.begin() + length, dest.end());
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else if (result == Z_MEM_ERROR)
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throw std::bad_alloc();
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else if (result == Z_STREAM_ERROR)
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throw std::ios_base::failure("invalid level");
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}
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private:
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int level_;
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};
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</PRE>
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<!-- Begin Footer -->
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<HR>
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<P CLASS="copyright">Revised
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<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->
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20 May, 2004
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<!--webbot bot="Timestamp" endspan i-checksum="38504" -->
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</P>
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<P CLASS="copyright">© Copyright Jonathan Turkanis, 2004</P>
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<P CLASS="copyright">
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Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at <A HREF="http://www.boost.org/LICENSE_1_0.txt">http://www.boost.org/LICENSE_1_0.txt</A>)
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</P>
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<!-- End Footer -->
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</BODY>
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