Botan::Zlib_Compression Class Reference

#include <zlib.h>

Inheritance diagram for Botan::Zlib_Compression:

Public Member Functions
virtual bool	attachable ()
void	end_msg ()
void	flush ()
std::string	name () const
void	start_msg ()
void	write (const byte input[], size_t length)
	Zlib_Compression (size_t level=6)
	~Zlib_Compression ()

Protected Member Functions
void	send (byte in)
void	send (const byte in[], size_t length)
void	send (const MemoryRegion< byte > &in)
void	send (const MemoryRegion< byte > &in, size_t length)

Detailed Description

Zlib Compression Filter

Definition at line 19 of file zlib.h.

Constructor & Destructor Documentation

Zlib_Compression()

Botan::Zlib_Compression::Zlib_Compression

(

size_t

level = 6

)

Parameters

level

how much effort to use on compressing (0 to 9); higher levels are slower but tend to give better compression

Definition at line 94 of file zlib.cpp.

                                           :
   level((l >= 9) ? 9 : l), buffer(DEFAULT_BUFFERSIZE)
   {
   zlib = 0;
   }

~Zlib_Compression()

Botan::Zlib_Compression::~Zlib_Compression ( )

inline

Definition at line 39 of file zlib.h.

{ clear(); }

Member Function Documentation

attachable()

virtual bool Botan::Filter::attachable ( )

inlinevirtualinherited

Check whether this filter is an attachable filter.

Returns

true if this filter is attachable, false otherwise

Reimplemented in Botan::DataSink, and Botan::SecureQueue.

Definition at line 50 of file filter.h.

{ return true; }

end_msg()

void Botan::Zlib_Compression::end_msg ( )

virtual

Notify that the current message is finished; flush buffers and do end-of-message processing (if any).

Reimplemented from Botan::Filter.

Definition at line 131 of file zlib.cpp.

   {
   zlib->stream.next_in = 0;
   zlib->stream.avail_in = 0;
 
   int rc = Z_OK;
   while(rc != Z_STREAM_END)
      {
      zlib->stream.next_out = reinterpret_cast<Bytef*>(buffer.begin());
      zlib->stream.avail_out = buffer.size();
 
      rc = deflate(&(zlib->stream), Z_FINISH);
      send(buffer.begin(), buffer.size() - zlib->stream.avail_out);
      }
 
   clear();
   }

References Botan::Filter::send().

flush()

void Botan::Zlib_Compression::flush

(

)

Flush the compressor

Definition at line 152 of file zlib.cpp.

   {
   zlib->stream.next_in = 0;
   zlib->stream.avail_in = 0;
 
   while(true)
      {
      zlib->stream.avail_out = buffer.size();
      zlib->stream.next_out = reinterpret_cast<Bytef*>(buffer.begin());
 
      deflate(&(zlib->stream), Z_FULL_FLUSH);
      send(buffer.begin(), buffer.size() - zlib->stream.avail_out);
 
      if(zlib->stream.avail_out == buffer.size())
        break;
      }
   }

References Botan::Filter::send().

name()

std::string Botan::Zlib_Compression::name ( ) const

inlinevirtual

Returns

descriptive name for this filter

Implements Botan::Filter.

Definition at line 22 of file zlib.h.

{ return "Zlib_Compression"; }

send() [1/4]

void Botan::Filter::send ( byte in )

inlineprotectedinherited

Parameters

in	some input for the filter

Definition at line 63 of file filter.h.

{ send(&in, 1); }

References send().

Referenced by send().

send() [2/4]

void Botan::Filter::send ( const byte in[], size_t length )

protectedinherited

Parameters

in	some input for the filter
length	the length of in

Definition at line 28 of file filter.cpp.

   {
   bool nothing_attached = true;
   for(size_t j = 0; j != total_ports(); ++j)
      if(next[j])
         {
         if(write_queue.size())
            next[j]->write(&write_queue[0], write_queue.size());
         next[j]->write(input, length);
         nothing_attached = false;
         }
 
   if(nothing_attached)
      write_queue += std::make_pair(input, length);
   else
      write_queue.clear();
   }

Referenced by Botan::Base64_Decoder::end_msg(), Botan::Base64_Encoder::end_msg(), Botan::Bzip_Compression::end_msg(), Botan::Bzip_Decompression::end_msg(), Botan::Hash_Filter::end_msg(), Botan::Hex_Decoder::end_msg(), Botan::Hex_Encoder::end_msg(), Botan::MAC_Filter::end_msg(), Botan::PK_Decryptor_Filter::end_msg(), Botan::PK_Encryptor_Filter::end_msg(), Botan::PK_Signer_Filter::end_msg(), Botan::PK_Verifier_Filter::end_msg(), Botan::Zlib_Compression::end_msg(), Botan::Zlib_Decompression::end_msg(), Botan::Bzip_Compression::flush(), Botan::Zlib_Compression::flush(), send(), Botan::Base64_Decoder::write(), Botan::Bzip_Compression::write(), Botan::Bzip_Decompression::write(), Botan::Chain::write(), Botan::Fork::write(), Botan::Hex_Decoder::write(), Botan::StreamCipher_Filter::write(), Botan::Zlib_Compression::write(), and Botan::Zlib_Decompression::write().

send() [3/4]

void Botan::Filter::send ( const MemoryRegion< byte > & in )

inlineprotectedinherited

Parameters

in	some input for the filter

Definition at line 68 of file filter.h.

{ send(&in[0], in.size()); }

References send(), and Botan::MemoryRegion< T >::size().

Referenced by send().

send() [4/4]

void Botan::Filter::send ( const MemoryRegion< byte > & in, size_t length )

inlineprotectedinherited

Parameters

in	some input for the filter
length	the number of bytes of in to send

Definition at line 74 of file filter.h.

         {
         send(&in[0], length);
         }

References send().

start_msg()

void Botan::Zlib_Compression::start_msg ( )

virtual

Start a new message. Must be closed by end_msg() before another message can be started.

Reimplemented from Botan::Filter.

Definition at line 103 of file zlib.cpp.

   {
   clear();
   zlib = new Zlib_Stream;
   if(deflateInit(&(zlib->stream), level) != Z_OK)
      throw Memory_Exhaustion();
   }

write()

void Botan::Zlib_Compression::write ( const byte input[], size_t length )

virtual

Write a portion of a message to this filter.

Parameters

input	the input as a byte array
length	the length of the byte array input

Implements Botan::Filter.

Definition at line 114 of file zlib.cpp.

   {
   zlib->stream.next_in = static_cast<Bytef*>(const_cast<byte*>(input));
   zlib->stream.avail_in = length;
 
   while(zlib->stream.avail_in != 0)
      {
      zlib->stream.next_out = static_cast<Bytef*>(buffer.begin());
      zlib->stream.avail_out = buffer.size();
      deflate(&(zlib->stream), Z_NO_FLUSH);
      send(buffer.begin(), buffer.size() - zlib->stream.avail_out);
      }
   }

References Botan::Filter::send().

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The documentation for this class was generated from the following files:

• src/filters/zlib/zlib.h
• src/filters/zlib/zlib.cpp