#include <opennurbs_archive.h>

Public Types
enum	{ seek_from_beginning_of_file = 0, seek_from_current_position = 1, seek_from_end_of_file = 2 }

Public Member Functions
	ON_Buffer ()

	ON_Buffer (const ON_Buffer &src)

	~ON_Buffer ()

bool	AtEnd () const

bool	ChangeSize (ON__UINT64 buffer_size)

void	ClearLastError ()

bool	Compact ()
	Return unused memory to heap. More...

bool	Compress (ON_Buffer &compressed_buffer) const
	Compress this buffer More...

ON__UINT32	CRC32 (ON__UINT32 current_remainder) const

ON__UINT64	CurrentPosition () const

void	Destroy ()

void	EmergencyDestroy ()

ON_Buffer_ErrorHandler	ErrorHandler () const

bool	IsValid (const ON_TextLog *text_log) const

ON__UINT32	LastError () const

ON_Buffer &	operator= (const ON_Buffer &src)

ON__UINT64	Read (ON__UINT64 size, void *buffer)

bool	ReadFromBinaryArchive (ON_BinaryArchive &)
	Use ReadFromBinaryArchive() to retrieve an entire ON_Buffer that was written using WriteToBinaryArchive(). More...

bool	Seek (ON__INT64 offset, int origin)

bool	SeekFromCurrentPosition (ON__INT64 offset)

bool	SeekFromEnd (ON__INT64 offset)

bool	SeekFromStart (ON__INT64 offset)

void	SetErrorHandler (ON_Buffer_ErrorHandler error_handler)

ON__UINT64	Size () const

bool	Uncompress (ON_Buffer &uncompressed_buffer) const
	Uncompress this buffer which must have been compressed using ON_Buffer::Compress(). More...

ON__UINT64	Write (ON__UINT64 size, const void *buffer)

bool	WriteToBinaryArchive (ON_BinaryArchive &) const
	Use WriteToBinaryArchive() to save an entire ON_Buffer inside a binary archive. Use ReadFromBinaryArchive() to retrieve the ON_Buffer from the ON_BinaryArchive. More...

Static Public Member Functions
static int	Compare (const ON_Buffer &a, const ON_Buffer &b)
	Compare contents of buffers. Paramters: a - [in] b - [in] More...

Member Enumeration Documentation

◆ anonymous enum

anonymous enum

Enumerator
seek_from_beginning_of_file
seek_from_current_position
seek_from_end_of_file

Constructor & Destructor Documentation

◆ ON_Buffer() [1/2]

ON_Buffer::ON_Buffer ( )

◆ ~ON_Buffer()

ON_Buffer::~ON_Buffer ( )

◆ ON_Buffer() [2/2]

ON_Buffer::ON_Buffer ( const ON_Buffer & src )

Member Function Documentation

◆ AtEnd()

bool ON_Buffer::AtEnd ( ) const

Returns: True if Size() == CurrentPosition().

It is possible to seek beyond the end of the buffer. In this case, the current position will be past the end of the buffer and AtEnd() will return false.

◆ ChangeSize()

bool ON_Buffer::ChangeSize ( ON__UINT64 buffer_size )

Parameters

buffer_size [in] new size of buffer.

Returns: True if successful.

The current position is not changed and may be beyond the end of the file. Use Seek to set the current position after calling ChangeSize().

◆ ClearLastError()

void ON_Buffer::ClearLastError ( )

◆ Compact()

bool ON_Buffer::Compact ( )

Return unused memory to heap.

Call this function after creating an ON_Buffer that will persist for and extended amount of time. There are never more than 16 pages of unsued memory (16*4096 bytes on most computers) in an ON_Buffer. Compact() can be called at any time, but calling Compact() the then writing at the end of the buffer is not an efficient use of time or memory.

◆ Compare()

static int ON_Buffer::Compare	(	const ON_Buffer &	a,
		const ON_Buffer &	b
	)

static

Compare contents of buffers. Paramters: a - [in] b - [in]

Returns: -1: a < b 0: a == b 1: a > b

◆ Compress()

bool ON_Buffer::Compress ( ON_Buffer & compressed_buffer ) const

Compress this buffer

Parameters

compressed_buffer [out] (The reference can be *this)

Returns: True if successful. False if failed.

@verbatim
  // compress a buffer in place
  ON_Buffer buffer;
  buffer = ...;
  if ( !buffer.Compress(buffer) )
  {
     // compression failed
  }
  else
  {
     // buffer is now compressed
  }
@endverbatim

◆ CRC32()

ON__UINT32 ON_Buffer::CRC32 ( ON__UINT32 current_remainder ) const

Returns: 32-bit CRC of the buffer contents.

◆ CurrentPosition()

ON__UINT64 ON_Buffer::CurrentPosition ( ) const

Returns: Current position in the buffer.

It is possible to seek beyond the end of the buffer. In this case, the current position will be past the end of the buffer and CurrentPosition() will be greater than Size().

◆ Destroy()

void ON_Buffer::Destroy ( )

◆ EmergencyDestroy()

void ON_Buffer::EmergencyDestroy ( )

◆ ErrorHandler()

ON_Buffer_ErrorHandler ON_Buffer::ErrorHandler ( ) const

◆ IsValid()

bool ON_Buffer::IsValid ( const ON_TextLog * text_log ) const

◆ LastError()

ON__UINT32 ON_Buffer::LastError ( ) const

Returns: Value that identifies most recent error. 0: no error 1: attempt to seek to a negative position

◆ operator=()

ON_Buffer& ON_Buffer::operator= ( const ON_Buffer & src )

◆ Read()

ON__UINT64 ON_Buffer::Read	(	ON__UINT64	size,
		void *	buffer
	)

Parameters

size	[in] number of bytes to read.
buffer	[out] read values are returned in buffer.

Returns: Number of bytes read into buffer. For example, if CurrentPosition() <= Size() and size > (Size() - CurrentPosition()) and buffer is not null, then the value (Size() - CurrentPosition()) is returned.

If the size parameter is zero, then nothing is done. When CurrentPosition() <= Size(), attempts to read more than (Size() - CurrentPosition()) bytes do not generate an error. When CurrentPosition() > Size(), any attempt to read generates an error.

◆ ReadFromBinaryArchive()

bool ON_Buffer::ReadFromBinaryArchive ( ON_BinaryArchive & )

Use ReadFromBinaryArchive() to retrieve an entire ON_Buffer that was written using WriteToBinaryArchive().

◆ Seek()

bool ON_Buffer::Seek	(	ON__INT64	offset,
		int	origin
	)

Parameters

offset	[in] number of bytes to seek from origin
origin	[in] initial position. 0 (SEEK_SET) Seek from beginning of file. 1 (SEEK_CUR) Seek from current position. 2 (SEEK_END) Seek from end of file.

Returns: True if successful. False if the seek would result in a file position before the beginning of the file. If false is returned, the current position is not changed.

Seeking beyond the end of the buffer is succeeds. Seeking before the beginning of the buffer fails.

◆ SeekFromCurrentPosition()

bool ON_Buffer::SeekFromCurrentPosition ( ON__INT64 offset )

Parameters

offset [in] number of bytes to seek from the current position.

Returns: True if successful. False if the seek would result in a file position before the beginning of the file. If false is returned, the current position is not changed.

Seeking beyond the end of the buffer is succeeds. Seeking before the beginning of the buffer fails.

◆ SeekFromEnd()

bool ON_Buffer::SeekFromEnd ( ON__INT64 offset )

Parameters

offset [in] number of bytes to seek from the end fo the buffer.

Returns: True if successful. False if the seek would result in a file position before the beginning of the file. If false is returned, the current position is not changed.

Seeking beyond the end of the buffer is succeeds. Seeking before the beginning of the buffer fails.

◆ SeekFromStart()

bool ON_Buffer::SeekFromStart ( ON__INT64 offset )

Parameters

offset [in] (>= 0) number of bytes to seek from the start of the buffer.

Returns: True if successful. False if the seek would result in a file position before the beginning of the file. If false is returned, the current position is not changed.

Seeking beyond the end of the buffer is succeeds. Seeking before the beginning of the buffer fails.

◆ SetErrorHandler()

void ON_Buffer::SetErrorHandler ( ON_Buffer_ErrorHandler error_handler )

◆ Size()

ON__UINT64 ON_Buffer::Size ( ) const

Returns: Number of bytes currently in the buffer.

It is possible to seek beyond the end of the buffer. In this case, the current position will be past the end of the buffer and CurrentPosition() will be greater than Size().

◆ Uncompress()

bool ON_Buffer::Uncompress ( ON_Buffer & uncompressed_buffer ) const

Uncompress this buffer which must have been compressed using ON_Buffer::Compress().

Parameters

uncompressed_buffer [out] (The reference can be *this)

Returns: True if successful. False if failed.

// silly example that compresses and then uncompresses a buffer in place
// to show how to call the functions.
ON_Buffer buffer;
buffer = ...; // buffer is in it uncompressed form
if ( buffer.Compress(buffer) )
{
   // buffer is now compressed
   if ( buffer.Uncompress(buffer) )
   {
      // buffer is uncompressed again.
   }
}

◆ Write()

ON__UINT64 ON_Buffer::Write	(	ON__UINT64	size,
		const void *	buffer
	)

Parameters

size	[in] number of bytes to write.
buffer	[in] values to write.

Returns: Number of bytes written buffer.

◆ WriteToBinaryArchive()

bool ON_Buffer::WriteToBinaryArchive ( ON_BinaryArchive & ) const

Use WriteToBinaryArchive() to save an entire ON_Buffer inside a binary archive. Use ReadFromBinaryArchive() to retrieve the ON_Buffer from the ON_BinaryArchive.

Public Types

Public Member Functions

Static Public Member Functions

Member Enumeration Documentation

◆ anonymous enum

Constructor & Destructor Documentation

◆ ON_Buffer() [1/2]

◆ ~ON_Buffer()

◆ ON_Buffer() [2/2]

Member Function Documentation

◆ AtEnd()

◆ ChangeSize()

◆ ClearLastError()

◆ Compact()

◆ Compare()

◆ Compress()

◆ CRC32()

◆ CurrentPosition()

◆ Destroy()

◆ EmergencyDestroy()

◆ ErrorHandler()

◆ IsValid()

◆ LastError()

◆ operator=()

◆ Read()

◆ ReadFromBinaryArchive()

◆ Seek()

◆ SeekFromCurrentPosition()

◆ SeekFromEnd()

◆ SeekFromStart()

◆ SetErrorHandler()

◆ Size()

◆ Uncompress()

◆ Write()

◆ WriteToBinaryArchive()