Overview

Implements the pw::stream::Reader interface by backing the data source with an externally provided memory buffer.

Inheritance diagram for pw::stream::MemoryReader:

Public Member Functions
constexpr	MemoryReader (ConstByteSpan source)

size_t	bytes_read () const

const std::byte *	data () const

Public Member Functions inherited from pw::stream::Stream
constexpr bool	readable () const

constexpr bool	writable () const

constexpr bool	seekable () const

constexpr bool	seekable (Whence origin) const
	True if the stream supports seeking from the specified origin.

Result< ByteSpan >	Read (ByteSpan dest)

Result< ByteSpan >	Read (void *dest, size_t size_bytes)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Result< ByteSpan >	ReadExact (ByteSpan const buffer)

Status	Write (ConstByteSpan data)

Status	Write (const void *data, size_t size_bytes)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Status	Write (const std::byte b)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Status	Seek (ptrdiff_t offset, Whence origin=kBeginning)

size_t	Tell ()

size_t	ConservativeReadLimit () const

size_t	ConservativeWriteLimit () const

Private Member Functions
size_t	ConservativeLimit (LimitType type) const override

Status	DoSeek (ptrdiff_t offset, Whence origin) override
	Virtual Seek() function implemented by derived classes.

size_t	DoTell () override

StatusWithSize	DoRead (ByteSpan dest) override
	Virtual Read() function implemented by derived classes.

Additional Inherited Members
Public Types inherited from pw::stream::Stream
enum	Whence : uint8_t { kBeginning = 0b001 , kCurrent = 0b010 , kEnd = 0b100 }
	Positions from which to seek. More...

Static Public Attributes inherited from pw::stream::Stream
static constexpr size_t	kUnlimited = std::numeric_limits<size_t>::max()
	Value returned from read/write limit if unlimited.

static constexpr size_t	kUnknownPosition = std::numeric_limits<size_t>::max()
	Returned by Tell() if getting the position is not supported.

Protected Types inherited from pw::stream::Stream
enum class	LimitType : bool { kRead , kWrite }

Member Function Documentation

size_t pw::stream::MemoryReader::ConservativeLimit ( LimitType limit_type ) const

inlineoverrideprivatevirtual

Virtual function optionally implemented by derived classes that is used for ConservativeReadLimit() and ConservativeWriteLimit().

The default implementation returns kUnlimited or 0 depending on whether the stream is readable/writable.

Reimplemented from pw::stream::Stream.

StatusWithSize pw::stream::MemoryReader::DoRead ( ByteSpan destination )

overrideprivatevirtual

Virtual Read() function implemented by derived classes.

Status pw::stream::MemoryReader::DoSeek	(	ptrdiff_t	offset,
		Whence	origin
	)

inlineoverrideprivatevirtual

Virtual Seek() function implemented by derived classes.

size_t pw::stream::MemoryReader::DoTell ( )

inlineoverrideprivatevirtual

Virtual Tell() function optionally implemented by derived classes. The default implementation always returns kUnknownPosition.

Reimplemented from pw::stream::Stream.

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