Detailed Description

PacketBuffer with heap allocation (in stream mode).

(As PacketBufferHeap, but ignores packet boundaries.)

Definition at line 148 of file posix_utils.h.

#include <posix_utils.h>

Inheritance diagram for satcat5::io::StreamBufferHeap:

Collaboration diagram for satcat5::io::StreamBufferHeap:

Public Member Functions
	StreamBufferHeap (unsigned nbytes=4096)

void	clear ()
	Reset buffer contents. More...

unsigned	byte_count (bool reset=true) override
	Bytes transferred since the last query.

unsigned	frame_count (bool reset=true) override
	Frames transferred since the last query.

u8	get_percent_full () const
	Get overall buffer occupancy as percentage full (0-100%).

unsigned	get_write_partial () const
	Get number of bytes in a partial packet, or -1 on overflow.

unsigned	get_write_space () const override
	How many bytes can be written without blocking? More...

void	write_bytes (unsigned nbytes, const void *src) override
	Write 0 or more bytes from a buffer. More...

void	write_abort () override
	If possible, abort the current partially-written packet. More...

bool	write_finalize () override
	Mark end of frame and release temporary working data. More...

void	zcw_write (unsigned nbytes)
	Zero-copy write (zcw) mode, required for UART interface. More...

unsigned	zcw_maxlen () const
	Max contiguous write length (ZCW).

u8 *	zcw_start ()
	Pointer to a contiguous buffer (ZCW).

unsigned	get_read_ready () const override
	How many bytes can be read without blocking? More...

bool	read_bytes (unsigned nbytes, void *dst) override
	Read 0 or more bytes into a buffer. More...

bool	read_consume (unsigned nbytes) override
	Read and discard 0 or more bytes. More...

void	read_finalize () override
	Consume any remaining bytes in this frame, if applicable. More...

const u8 *	peek (unsigned nbytes) const
	Peek `nbytes` into the circular buffer. More...

unsigned	get_peek_ready () const
	Find the longest available contiguous segment that can be requested by peek().

void	write_u8 (u8 data)
	One of many functions for writing integer/floating point values, see details. More...

void	write_str (const char *str)
	Write the contents of a null-terminated string. More...

template<class T >
void	write_obj (const T &obj)
	Templated wrapper for any object with the following method: `void write_to(satcat5::io::Writeable* wr) const;`

virtual void	set_callback (satcat5::io::EventListener *callback)
	Update registered callback for data_rcvd() events. More...

u8	read_u8 ()
	One of many functions for reading integer/floating point values, see details. More...

unsigned	read_str (unsigned dst_size, char *dst)
	Safely read a null-terminated input string. More...

template<class T >
bool	read_obj (T &t)
	Templated wrapper for any object with the following method: `bool read_from(satcat5::io::Readable* rd);`

unsigned	copy_to (satcat5::io::Writeable *dst)
	Copy data to a Writeable object, without finalizing. More...

bool	copy_and_finalize (satcat5::io::Writeable *dst, satcat5::io::CopyMode mode=CopyMode::PACKET)
	Copy data to a Writeable object, then finalize. More...

void	request_poll ()
	Call this method to request polling at a later time. More...

void	request_cancel ()
	Call this method to cancel a previous request_poll().

virtual unsigned	error_count (bool reset=true)
	(Optional) Error events since the last query.


u8 *	get_buff_dtor () const
	Accessor for children that need to delete underlying buffer. More...

unsigned	get_buff_size () const
	Accessor for children that need to delete underlying buffer. More...

Static Public Member Functions
static unsigned	count_ondemand ()
	Count queued objects of this type (i.e., non-idle).

Protected Member Functions
void	write_next (u8 data) override
	Write the next byte to the underlying buffer or device. More...

void	write_overflow () override
	Optional error handling for write overflow. More...

u8	read_next () override
	Read the next byte from the underlying buffer or device. More...

bool	can_read_internal (unsigned nbytes) const

void	consume_internal (unsigned nbytes)

void	read_notify ()
	Attempt notification by calling `m_callback->data_rcvd()`. More...

virtual void	read_underflow ()
	Optional error handling for read underflow. More...

Protected Attributes
u8 *const	m_buffptr
	Pointer to the underlying buffer.

friend	LimitedWrite

friend	WriteableBroadcast

friend	WriteableRedirect

Private Member Functions
void	poll_demand ()
	Event handler for on-demand polling.

Private Attributes
satcat5::io::EventListener *	m_callback
	Pointer to the callback object, or NULL. More...

satcat5::poll::OnDemand *	m_next

bool	m_idle


u8 *const	m_buff
	State for the main circular buffer (read domain)

const unsigned	m_buff_size
	State for the main circular buffer (read domain)

unsigned	m_buff_rdidx
	State for the main circular buffer (read domain)

unsigned	m_buff_rdcount
	State for the main circular buffer (read domain)


u16 *const	m_pkt_lbuff
	Store packet lengths in an auxiliary buffer (read domain)

const unsigned	m_pkt_maxct
	Store packet lengths in an auxiliary buffer (read domain)

unsigned	m_pkt_rdidx
	Store packet lengths in an auxiliary buffer (read domain)


unsigned	m_total_bytes
	Cumulative total-bytes and total-frames statistics counters.

unsigned	m_total_frames
	Cumulative total-bytes and total-frames statistics counters.


unsigned	m_next_wrpos
	Working state for writes (write domain)

unsigned	m_next_wrlen
	Working state for writes (write domain)


volatile unsigned	m_shared_rdavail
	Shared state is constant except for cross-domain events.

volatile unsigned	m_shared_pktcount
	Shared state is constant except for cross-domain events.

Member Function Documentation

◆ clear()

void PacketBuffer::clear ( )

inherited

Reset buffer contents.

Note: This does not reset byte_count and frame_count.

Definition at line 22 of file pkt_buffer.cc.

◆ copy_and_finalize()

bool Readable::copy_and_finalize	(	satcat5::io::Writeable *	dst,
		satcat5::io::CopyMode	mode = `CopyMode::PACKET`
	)

inherited

Copy data to a Writeable object, then finalize.

As copy_to(), but also calls read_finalize() and/or write_finalize() depending on the input/output mode.

In packet mode (the default), call both read_finalize() and write_finalize() if the operation copies all available data. Use this mode whenever the input is packetized.

In byte-stream mode, call write_finalize() if the operation copies any data, but never call read_finalize(). Use this mode for inputs that do not delimit packet boundaries.

Parameters

dst	The destination object.
mode	Select packet mode or stream mode.

Returns: True if the output was finalized successfully.

Definition at line 234 of file io_readable.cc.

◆ copy_to()

unsigned Readable::copy_to ( satcat5::io::Writeable * dst )

inherited

Copy data to a Writeable object, without finalizing.

Copy the contents of this Readable to a Writeable object, stopping at end-of-input, end-of-frame, or the capacity of the destination buffer (whichever comes first). This method does not call read_finalize or write_finalize(). To automatically make finalize calls,

See also: copy_and_finalize.

Returns: The number of bytes copied.

Definition at line 214 of file io_readable.cc.

◆ get_buff_dtor()

u8* satcat5::io::PacketBuffer::get_buff_dtor ( ) const

inlineinherited

Accessor for children that need to delete underlying buffer.

Returned value matches pointer passed to the constructor.

Definition at line 137 of file pkt_buffer.h.

◆ get_buff_size()

unsigned satcat5::io::PacketBuffer::get_buff_size ( ) const

inlineinherited

Accessor for children that need to delete underlying buffer.

Returned value matches pointer passed to the constructor.

Definition at line 138 of file pkt_buffer.h.

◆ get_read_ready()

unsigned PacketBuffer::get_read_ready ( ) const

overridevirtualinherited

How many bytes can be read without blocking?

Child objects of io::Readable MUST override this method.

Implements satcat5::io::Readable.

Definition at line 177 of file pkt_buffer.cc.

◆ get_write_space()

unsigned PacketBuffer::get_write_space ( ) const

overridevirtualinherited

How many bytes can be written without blocking?

Child objects of io::Writeable MUST override this method.

Implements satcat5::io::Writeable.

Definition at line 52 of file pkt_buffer.cc.

◆ peek()

const u8 * PacketBuffer::peek ( unsigned nbytes ) const

inherited

Peek nbytes into the circular buffer.

Due to this circular buffer, packet data may not be contiguous. Use get_peek_ready() to find the longest available contiguous segment.

Returns: A pointer to packet data, or NULL if nbytes > get_peek_ready().

Definition at line 248 of file pkt_buffer.cc.

◆ read_bytes()

bool PacketBuffer::read_bytes	(	unsigned	nbytes,
		void *	dst
	)

overridevirtualinherited

Read 0 or more bytes into a buffer.

Child objects of io::Readable MAY override this method for improved performance.

Reimplemented from satcat5::io::Readable.

Definition at line 187 of file pkt_buffer.cc.

◆ read_consume()

bool PacketBuffer::read_consume ( unsigned nbytes )

overridevirtualinherited

Read and discard 0 or more bytes.

Child objects of io::Readable MAY override this method for improved performance.

Reimplemented from satcat5::io::Readable.

Definition at line 256 of file pkt_buffer.cc.

◆ read_finalize()

void PacketBuffer::read_finalize ( )

overridevirtualinherited

Consume any remaining bytes in this frame, if applicable.

Child objects of io::Readable SHOULD override this method if they support framing.

Reimplemented from satcat5::io::Readable.

Definition at line 266 of file pkt_buffer.cc.

◆ read_next()

u8 PacketBuffer::read_next ( )

overrideprotectedvirtualinherited

Read the next byte from the underlying buffer or device.

Child objects of io::Readable MUST override this method.

Implements satcat5::io::Readable.

Definition at line 206 of file pkt_buffer.cc.

◆ read_notify()

void Readable::read_notify ( )

protectedinherited

Attempt notification by calling m_callback->data_rcvd().

Child objects of io::Readable MAY call this to override default notifications.

Definition at line 254 of file io_readable.cc.

◆ read_str()

unsigned Readable::read_str	(	unsigned	dst_size,
		char *	dst
	)

inherited

Safely read a null-terminated input string.

The input is always consumed up to the end-of-input or the first zero byte, whichever comes first.

Returns: The length of the output string, which may be truncated as needed to fit in the provided buffer.

Definition at line 179 of file io_readable.cc.

◆ read_u8()

u8 Readable::read_u8 ( )

inherited

One of many functions for reading integer/floating point values, see details.

Several functions are provided for reading and writing scalar types to/from io::Readable and io::Writeable instances. Since there are many of these that are frequently inherited, they are hidden from documentation. These functions follow a shared template:

read_ or write_ prefix.
u for unsigned, s for signed, f for floating-point.
Data-type width in bits.
- Available widths for ints: 8/16/24/32/48/64.
- Available widths for floats: 32/64.
l suffix if little-endian, no suffix if big-endian.

Example: write_s48l is "Write 48 bits (6 bytes) to this io::Writeable as a signed value in little-endian order".

Definition at line 44 of file io_readable.cc.

◆ read_underflow()

void Readable::read_underflow ( )

protectedvirtualinherited

Optional error handling for read underflow.

Child objects of io::Readable MAY override this method.

Reimplemented in satcat5::port::Mailmap, and satcat5::io::ReadableRedirect.

Definition at line 271 of file io_readable.cc.

◆ request_poll()

void satcat5::poll::OnDemand::request_poll ( )

inherited

Call this method to request polling at a later time.

Safe to stack requests, but only one call to poll().

Definition at line 208 of file polling.cc.

◆ set_callback()

void Readable::set_callback ( satcat5::io::EventListener * callback )

virtualinherited

Update registered callback for data_rcvd() events.

Child objects of io::Readable SHOULD usually leave this method as-is.

Reimplemented in satcat5::io::ReadableRedirect, satcat5::io::Override, satcat5::io::MuxPort, and satcat5::test::EthernetInterface.

Definition at line 39 of file io_readable.cc.

◆ write_abort()

void PacketBuffer::write_abort ( )

overridevirtualinherited

If possible, abort the current partially-written packet.

Child objects of io::Writeable SHOULD override this method if it is practical to prevent in-progress data from being relayed downstream.

Reimplemented from satcat5::io::Writeable.

Definition at line 89 of file pkt_buffer.cc.

◆ write_bytes()

void PacketBuffer::write_bytes	(	unsigned	nbytes,
		const void *	src
	)

overridevirtualinherited

Write 0 or more bytes from a buffer.

Child objects of io::Writeable MAY override write_bytes as needed for performance.

Reimplemented from satcat5::io::Writeable.

Definition at line 73 of file pkt_buffer.cc.

◆ write_finalize()

bool PacketBuffer::write_finalize ( )

overridevirtualinherited

Mark end of frame and release temporary working data.

Child objects of io::Writeable SHOULD override this method to mark frame bounds.

Returns: True if successful, false on error.

Reimplemented from satcat5::io::Writeable.

Definition at line 105 of file pkt_buffer.cc.

◆ write_next()

void PacketBuffer::write_next ( u8 data )

overrideprotectedvirtualinherited

Write the next byte to the underlying buffer or device.

Child objects of io::Writeable MUST override this method.

Implements satcat5::io::Writeable.

Definition at line 93 of file pkt_buffer.cc.

◆ write_overflow()

void PacketBuffer::write_overflow ( )

overrideprotectedvirtualinherited

Optional error handling for write overflow.

Child objects of io::Writeable MAY override this method for error handling.

Reimplemented from satcat5::io::Writeable.

Definition at line 101 of file pkt_buffer.cc.

◆ write_str()

void Writeable::write_str ( const char * str )

inherited

Write the contents of a null-terminated string.

Note: Null-termination is not copied to the output.

Definition at line 180 of file io_writeable.cc.

◆ write_u8()

void Writeable::write_u8 ( u8 data )

inherited

One of many functions for writing integer/floating point values, see details.

Several functions are provided for reading and writing scalar types to/from io::Readable and io::Writeable instances. Since there are many of these that are frequently inherited, they are hidden from documentation. These functions follow a shared template:

read_ or write_ prefix.
u for unsigned, s for signed, f for floating-point.
Data-type width in bits.
- Available widths for ints: 8/16/24/32/48/64.
- Available widths for floats: 32/64.
l suffix if little-endian, no suffix if big-endian.

Example: write_s48l is "Write 48 bits (6 bytes) to this io::Writeable as a signed value in little-endian order".

Definition at line 20 of file io_writeable.cc.

◆ zcw_write()

void PacketBuffer::zcw_write ( unsigned nbytes )

inherited

Zero-copy write (zcw) mode, required for UART interface.

Create an AtomicLock object to ensure thread safety (MANDATORY).
Call zcw_maxlen() to find maximum contiguous write length.
Call zcw_start() to get a pointer to that contiguous buffer.
Call zcw_write(N) once those bytes have been written.

Definition at line 164 of file pkt_buffer.cc.

Member Data Documentation

◆ m_callback

satcat5::io::EventListener* satcat5::io::Readable::m_callback

privateinherited

Pointer to the callback object, or NULL.

This can only be modified through the set_callback(...) method.

Definition at line 199 of file io_readable.h.

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

Detailed Description

Public Member Functions

Static Public Member Functions

Protected Member Functions

Protected Attributes

Private Member Functions

Private Attributes

Member Function Documentation

◆ clear()

◆ copy_and_finalize()

◆ copy_to()

◆ get_buff_dtor()

◆ get_buff_size()

◆ get_read_ready()

◆ get_write_space()

◆ peek()

◆ read_bytes()

◆ read_consume()

◆ read_finalize()

◆ read_next()

◆ read_notify()

◆ read_str()

◆ read_u8()

◆ read_underflow()

◆ request_poll()

◆ set_callback()

◆ write_abort()

◆ write_bytes()

◆ write_finalize()

◆ write_next()

◆ write_overflow()

◆ write_str()

◆ write_u8()

◆ zcw_write()

Member Data Documentation

◆ m_callback