Botan::Hex_Decoder Class Reference

#include <filters.h>

Inheritance diagram for Botan::Hex_Decoder:

Public Member Functions
virtual bool	attachable ()
void	end_msg () override
	Hex_Decoder (Decoder_Checking checking=NONE)
std::string	name () const override
virtual void	start_msg ()
void	write (const uint8_t input[], size_t length) override

Protected Member Functions
virtual void	send (const uint8_t in[], size_t length)
void	send (std::span< const uint8_t > in)
void	send (std::span< const uint8_t > in, size_t length)
void	send (uint8_t in)

Detailed Description

Converts hex strings to bytes

Definition at line 739 of file filters.h.

Constructor & Destructor Documentation

Hex_Decoder()

Botan::Hex_Decoder::Hex_Decoder ( Decoder_Checking checking = NONE )

explicit

Construct a Hex Decoder using the specified character checking.

Parameters

checking

the checking to use during decoding.

Definition at line 99 of file hex_filt.cpp.

                                           : m_checking(c) {
   m_in.resize(HEX_CODEC_BUFFER_SIZE);
   m_out.resize(m_in.size() / 2);
}

References Botan::HEX_CODEC_BUFFER_SIZE.

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 53 of file filter.h.

{ return true; }

end_msg()

void Botan::Hex_Decoder::end_msg ( )

overridevirtual

Complete the decoding and flush any buffered output

Reimplemented from Botan::Filter.

Definition at line 150 of file hex_filt.cpp.

                          {
   size_t consumed = 0;
   const size_t written =
      hex_decode(m_out.data(), cast_uint8_ptr_to_char(m_in.data()), m_position, consumed, m_checking != FULL_CHECK);
 
   send(m_out, written);
 
   const bool not_full_bytes = consumed != m_position;
 
   m_position = 0;
 
   if(not_full_bytes) {
      throw Invalid_Argument("Hex_Decoder: Input not full bytes");
   }
}

References Botan::cast_uint8_ptr_to_char(), Botan::FULL_CHECK, Botan::hex_decode(), and Botan::Filter::send().

name()

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

inlineoverridevirtual

Return a descriptive name for this filter

Returns

"Hex_Decoder"

Implements Botan::Filter.

Definition at line 745 of file filters.h.

{ return "Hex_Decoder"; }

send() [1/4]

void Botan::Filter::send ( const uint8_t in[], size_t length )

protectedvirtualinherited

Send some bytes to the next filter in the chain

Parameters

in	some input for the filter
length	the length of in

Definition at line 30 of file filter.cpp.

                                                      {
   if(length == 0) {
      return;
   }
 
   bool nothing_attached = true;
   for(size_t j = 0; j != total_ports(); ++j) {
      if(m_next[j] != nullptr) {
         if(!m_write_queue.empty()) {
            m_next[j]->write(m_write_queue.data(), m_write_queue.size());
         }
         m_next[j]->write(input, length);
         nothing_attached = false;
      }
   }
 
   if(nothing_attached) {
      m_write_queue += std::make_pair(input, length);
   } else {
      m_write_queue.clear();
   }
}

Referenced by Botan::Base64_Decoder::end_msg(), Botan::Base64_Encoder::end_msg(), Botan::Hex_Decoder::end_msg(), Botan::Hex_Encoder::end_msg(), operator=(), send(), Botan::Base64_Decoder::write(), Botan::Chain::write(), Botan::Fork::write(), and Botan::Hex_Decoder::write().

send() [2/4]

void Botan::Filter::send ( std::span< const uint8_t > in )

inlineprotectedinherited

Send some bytes to the next filter in the chain

Parameters

in	some input for the filter

Definition at line 83 of file filter.h.

{ send(in.data(), in.size()); }

References send().

Referenced by send().

send() [3/4]

void Botan::Filter::send ( std::span< const uint8_t > in, size_t length )

protectedinherited

Send some bytes to the next filter in the chain

Parameters

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

This previously took a std::vector, for which the length field (allowing using just a prefix of the vector) somewhat made sense. It makes less sense now that we are using a span here; you can just use first to get a prefix.

Definition at line 22 of file filter.cpp.

                                                          {
   BOTAN_ASSERT_NOMSG(length <= in.size());
   send(in.data(), length);
}

References BOTAN_ASSERT_NOMSG, and send().

send() [4/4]

void Botan::Filter::send ( uint8_t in )

inlineprotectedinherited

Send some bytes to the next filter in the chain

Parameters

in	some input for the filter

Definition at line 76 of file filter.h.

{ send(&in, 1); }

References send().

Referenced by send().

start_msg()

virtual void Botan::Filter::start_msg ( )

inlinevirtualinherited

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

Definition at line 41 of file filter.h.

{}

write()

void Botan::Hex_Decoder::write ( const uint8_t input[], size_t length )

overridevirtual

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 117 of file hex_filt.cpp.

                                                            {
   const bool ignore_ws = (m_checking != FULL_CHECK);
 
   size_t pos = 0;
   while(pos < length) {
      // Drop ignored whitespace before buffering so a partial trailing nibble
      // stays next to its pair and the fixed buffer can't fill with whitespace.
      while(pos < length && m_position < m_in.size()) {
         const uint8_t c = input[pos++];
         if(ignore_ws && hex_ignorable_whitespace(c)) {
            continue;
         }
         m_in[m_position++] = c;
      }
 
      size_t consumed = 0;
      const size_t written =
         hex_decode(m_out.data(), cast_uint8_ptr_to_char(m_in.data()), m_position, consumed, ignore_ws);
 
      send(m_out, written);
 
      if(consumed != m_position) {
         copy_mem(m_in.data(), m_in.data() + consumed, m_position - consumed);
         m_position = m_position - consumed;
      } else {
         m_position = 0;
      }
   }
}

References Botan::cast_uint8_ptr_to_char(), Botan::copy_mem(), Botan::FULL_CHECK, Botan::hex_decode(), and Botan::Filter::send().

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

• src/lib/filters/filters.h
• src/lib/filters/hex_filt.cpp