Botan::DataSource_Memory Class Reference

#include <data_src.h>

Inheritance diagram for Botan::DataSource_Memory:

Public Member Functions
bool	check_available (size_t n) override
	DataSource_Memory (const std::vector< uint8_t > &in)
	DataSource_Memory (const uint8_t in[], size_t length)
	DataSource_Memory (secure_vector< uint8_t > in)
	DataSource_Memory (std::span< const uint8_t > in)
	DataSource_Memory (std::string_view in)
size_t	discard_next (size_t N)
bool	end_of_data () const override
size_t	get_bytes_read () const override
virtual std::string	id () const
size_t	peek (uint8_t buf[], size_t length, size_t offset) const override
size_t	peek_byte (uint8_t &out) const
size_t	read (uint8_t buf[], size_t length) override
std::optional< uint8_t >	read_byte ()
size_t	read_byte (uint8_t &out)

Detailed Description

This class represents a Memory-Based DataSource

Definition at line 126 of file data_src.h.

Constructor & Destructor Documentation

DataSource_Memory() [1/5]

Botan::DataSource_Memory::DataSource_Memory ( std::string_view in )

explicit

Construct a memory source that reads from a string

Parameters

in	the string to read from

Definition at line 108 of file data_src.cpp.

: DataSource_Memory(as_span_of_bytes(in)) {}

References Botan::as_span_of_bytes(), and DataSource_Memory().

Referenced by DataSource_Memory(), DataSource_Memory(), and DataSource_Memory().

DataSource_Memory() [2/5]

Botan::DataSource_Memory::DataSource_Memory ( const uint8_t in[], size_t length )

inline

Construct a memory source that reads from a byte array

Parameters

in	the byte array to read from
length	the length of the byte array

Definition at line 169 of file data_src.h.

: DataSource_Memory(std::span<const uint8_t>(in, length)) {}

References DataSource_Memory().

DataSource_Memory() [3/5]

Botan::DataSource_Memory::DataSource_Memory ( secure_vector< uint8_t > in )

inlineexplicit

Construct a memory source that reads from a secure_vector

Parameters

in	the MemoryRegion to read from

Definition at line 175 of file data_src.h.

: m_source(std::move(in)), m_offset(0) {}

DataSource_Memory() [4/5]

Botan::DataSource_Memory::DataSource_Memory ( std::span< const uint8_t > in )

inlineexplicit

Construct a memory source that reads from an arbitrary byte buffer

Parameters

in	the MemoryRegion to read from

Definition at line 181 of file data_src.h.

                                                            : m_offset(0) {
         // Guard against forming a range from a null pointer (eg an empty span)
         if(!in.empty()) {
            m_source.assign(in.begin(), in.end());
         }
      }

DataSource_Memory() [5/5]

Botan::DataSource_Memory::DataSource_Memory ( const std::vector< uint8_t > & in )

inlineexplicit

Construct a memory source that reads from a std::vector

Parameters

in	the MemoryRegion to read from

Definition at line 192 of file data_src.h.

: DataSource_Memory(std::span<const uint8_t>(in)) {}

References DataSource_Memory().

Member Function Documentation

check_available()

bool Botan::DataSource_Memory::check_available ( size_t n )

overridevirtual

Test whether at least n further bytes can be read

Parameters

n	the number of bytes required

Returns

true if at least n bytes remain

Implements Botan::DataSource.

Definition at line 80 of file data_src.cpp.

                                                {
   return (n <= (m_source.size() - m_offset));
}

discard_next()

size_t Botan::DataSource::discard_next ( size_t N )

inherited

Discard the next N bytes of the data

Parameters

N	the number of bytes to discard

Returns

number of bytes actually discarded

Definition at line 53 of file data_src.cpp.

                                        {
   uint8_t buf[64] = {0};
   size_t discarded = 0;
 
   while(n > 0) {
      const size_t got = this->read(buf, std::min(n, sizeof(buf)));
      discarded += got;
      n -= got;
 
      if(got == 0) {
         break;
      }
   }
 
   return discarded;
}

References read().

end_of_data()

bool Botan::DataSource_Memory::end_of_data ( ) const

overridevirtual

Test whether the source still has data that can be read

Returns

true if there is no more data to read, false otherwise

Implements Botan::DataSource.

Definition at line 101 of file data_src.cpp.

                                          {
   return (m_offset == m_source.size());
}

get_bytes_read()

size_t Botan::DataSource_Memory::get_bytes_read ( ) const

inlineoverridevirtual

Count the bytes consumed from this source so far

Returns

number of bytes read so far

Implements Botan::DataSource.

Definition at line 198 of file data_src.h.

{ return m_offset; }

id()

virtual std::string Botan::DataSource::id ( ) const

inlinevirtualinherited

return the id of this data source

Returns

std::string representing the id of this data source

Reimplemented in Botan::DataSource_Stream.

Definition at line 68 of file data_src.h.

{ return ""; }

peek()

size_t Botan::DataSource_Memory::peek ( uint8_t buf[], size_t length, size_t offset ) const

overridevirtual

Read from the source without modifying the internal offset

Parameters

buf	the byte array to write the result to
length	the length of the byte array buf
offset	the offset into the stream to read at

Returns

length in bytes that was actually read and put into buf

Implements Botan::DataSource.

Definition at line 87 of file data_src.cpp.

                                                                                     {
   const size_t bytes_left = m_source.size() - m_offset;
   if(peek_offset >= bytes_left) {
      return 0;
   }
 
   const size_t got = std::min(bytes_left - peek_offset, length);
   copy_mem(out, &m_source[m_offset + peek_offset], got);
   return got;
}

References Botan::copy_mem().

peek_byte()

size_t Botan::DataSource::peek_byte ( uint8_t & out ) const

inherited

Peek at one byte.

Parameters

out	an output byte

Returns

length in bytes that was actually read and put into out

Definition at line 46 of file data_src.cpp.

                                               {
   return peek(&out, 1, 0);
}

References peek().

Referenced by Botan::ASN1::maybe_BER().

read()

size_t Botan::DataSource_Memory::read ( uint8_t buf[], size_t length )

overridevirtual

Read from the source, advancing the internal offset

Parameters

buf	the byte array to write the result to
length	the length of the byte array buf

Returns

length in bytes that was actually read and put into buf

Implements Botan::DataSource.

Definition at line 73 of file data_src.cpp.

                                                           {
   const size_t got = std::min<size_t>(m_source.size() - m_offset, length);
   copy_mem(out, m_source.data() + m_offset, got);
   m_offset += got;
   return got;
}

References Botan::copy_mem().

read_byte() [1/2]

std::optional< uint8_t > Botan::DataSource::read_byte ( )

inherited

Read one byte.

Returns nullopt if no further bytes are available

Definition at line 34 of file data_src.cpp.

                                           {
   uint8_t b = 0;
   if(this->read(&b, 1) == 1) {
      return b;
   } else {
      return {};
   }
}

References read().

read_byte() [2/2]

size_t Botan::DataSource::read_byte ( uint8_t & out )

inherited

Read one byte.

Parameters

out	the byte to read to

Returns

length in bytes that was actually read and put into out

Definition at line 27 of file data_src.cpp.

                                         {
   return read(&out, 1);
}

References read().

Referenced by Botan::PEM_Code::decode(), and Botan::ASN1::maybe_BER().

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

• src/lib/utils/data_src.h
• src/lib/utils/data_src.cpp