Collaboration diagram for Pipes:

Detailed Description

Macros
#define	_PIPE_DATA(name, buffer, size)
	Data part of a static pipe initializer. More...

#define	PIPE_DECL(name, buffer, size) pipe_t name = _PIPE_DATA(name, buffer, size)
	Static pipe initializer. More...

Data Structures
struct	pipe_t
	Structure representing a pipe object. More...

Functions
static size_t	pipe_write (pipe_t pp, const uint8_t bp, size_t n)
	Non-blocking pipe write. More...

static size_t	pipe_read (pipe_t pp, uint8_t bp, size_t n)
	Non-blocking pipe read. More...

void	chPipeObjectInit (pipe_t pp, uint8_t buf, size_t n)
	Initializes a `mailbox_t` object. More...

void	chPipeReset (pipe_t *pp)
	Resets a `pipe_t` object. More...

size_t	chPipeWriteTimeout (pipe_t pp, const uint8_t bp, size_t n, sysinterval_t timeout)
	Pipe write with timeout. More...

size_t	chPipeReadTimeout (pipe_t pp, uint8_t bp, size_t n, sysinterval_t timeout)
	Pipe read with timeout. More...

static size_t	chPipeGetSize (const pipe_t *pp)
	Returns the pipe buffer size as number of bytes. More...

static size_t	chPipeGetUsedCount (const pipe_t *pp)
	Returns the number of used byte slots into a pipe. More...

static size_t	chPipeGetFreeCount (const pipe_t *pp)
	Returns the number of free byte slots into a pipe. More...

static void	chPipeResume (pipe_t *pp)
	Terminates the reset state. More...

Macro Definition Documentation

#define _PIPE_DATA	(	name,
		buffer,
		size
	)

Value:

{                                    \
  (uint8_t *)(buffer),                                                      \
  (uint8_t *)(buffer) + size,                                               \
  (uint8_t *)(buffer),                                                      \
  (uint8_t *)(buffer),                                                      \
  (size_t)0,                                                                \
  false,                                                                    \
  NULL,                                                                     \
  NULL,                                                                     \
  _MUTEX_DATA(name.cmtx),                                                   \
  _MUTEX_DATA(name.wmtx),                                                   \
  _MUTEX_DATA(name.rmtx),                                                   \
}

Data part of a static pipe initializer.

This macro should be used when statically initializing a pipe that is part of a bigger structure.

Parameters

[in]	name	the name of the pipe variable
[in]	buffer	pointer to the pipe buffer array of `uint8_t`
[in]	size	number of `uint8_t` elements in the buffer array

Definition at line 88 of file chpipes.h.

#define PIPE_DECL	(	name,
		buffer,
		size
	)	pipe_t name = _PIPE_DATA(name, buffer, size)

Static pipe initializer.

Statically initialized pipes require no explicit initialization using chPipeObjectInit().

Parameters

[in]	name	the name of the pipe variable
[in]	buffer	pointer to the pipe buffer array of `uint8_t`
[in]	size	number of `uint8_t` elements in the buffer array

Definition at line 126 of file chpipes.h.

Function Documentation

static size_t pipe_write	(	pipe_t *	pp,
		const uint8_t *	bp,
		size_t	n
	)

static

Non-blocking pipe write.

The function writes data from a buffer to a pipe. The operation completes when the specified amount of data has been transferred or when the pipe buffer has been filled.

Parameters

[in]	pp	the pointer to an initialized `pipe_t` object
[in]	bp	pointer to the data buffer
[in]	n	the maximum amount of data to be transferred, the value 0 is reserved

Returns: The number of bytes effectively transferred.

Function Class:: Not an API, this function is for internal use only.

Definition at line 105 of file chpipes.c.

References pipe_t::buffer, chPipeGetFreeCount(), pipe_t::cnt, pipe_t::top, and pipe_t::wrptr.

Referenced by chPipeWriteTimeout().

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static size_t pipe_read	(	pipe_t *	pp,
		uint8_t *	bp,
		size_t	n
	)

static

Non-blocking pipe read.

The function reads data from a pipe into a buffer. The operation completes when the specified amount of data has been transferred or when the pipe buffer has been emptied.

Parameters

[in]	pp	the pointer to an initialized `pipe_t` object
[out]	bp	pointer to the data buffer
[in]	n	the maximum amount of data to be transferred, the value 0 is reserved

Returns: The number of bytes effectively transferred.

Function Class:: Not an API, this function is for internal use only.

Definition at line 156 of file chpipes.c.

References pipe_t::buffer, chPipeGetUsedCount(), pipe_t::cnt, pipe_t::rdptr, and pipe_t::top.

Referenced by chPipeReadTimeout().

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void chPipeObjectInit	(	pipe_t *	pp,
		uint8_t *	buf,
		size_t	n
	)

Initializes a mailbox_t object.

Parameters

[out]	pp	the pointer to the `pipe_t` structure to be initialized
[in]	buf	pointer to the pipe buffer as an array of `uint8_t`
[in]	n	number of elements in the buffer array

Function Class:: Initializer, this function just initializes an object and can be invoked before the kernel is initialized.

Definition at line 207 of file chpipes.c.

References pipe_t::buffer, chDbgCheck, pipe_t::cnt, pipe_t::rdptr, pipe_t::reset, pipe_t::rtr, pipe_t::top, pipe_t::wrptr, and pipe_t::wtr.

Referenced by chFactoryCreatePipe().

void chPipeReset ( pipe_t * pp )

Resets a pipe_t object.

All the waiting threads are resumed with status MSG_RESET and the queued data is lost.

Postcondition: The pipe is in reset state, all operations will fail and return MSG_RESET until the mailbox is enabled again using chPipeResumeX().

Parameters

[in] pp the pointer to an initialized pipe_t object

Function Class:: Normal API, this function can be invoked by regular system threads but not from within a lock zone.

Definition at line 236 of file chpipes.c.

References pipe_t::buffer, chDbgCheck, chSchRescheduleS(), chSysLock(), chSysUnlock(), chThdResumeI(), pipe_t::cnt, MSG_RESET, pipe_t::rdptr, pipe_t::reset, pipe_t::rtr, pipe_t::wrptr, and pipe_t::wtr.

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size_t chPipeWriteTimeout	(	pipe_t *	pp,
		const uint8_t *	bp,
		size_t	n,
		sysinterval_t	timeout
	)

Pipe write with timeout.

The function writes data from a buffer to a pipe. The operation completes when the specified amount of data has been transferred or after the specified timeout or if the pipe has been reset.

Parameters

[in]	pp	the pointer to an initialized `pipe_t` object
[in]	bp	pointer to the data buffer
[in]	n	the number of bytes to be written, the value 0 is reserved
[in]	timeout	the number of ticks before the operation timeouts, the following special values are allowed: TIME_IMMEDIATE immediate timeout. TIME_INFINITE no timeout.

Returns: The number of bytes effectively transferred. A number lower than n means that a timeout occurred or the pipe went in reset state.

Function Class:: Normal API, this function can be invoked by regular system threads but not from within a lock zone.

Definition at line 278 of file chpipes.c.

References chDbgCheck, chSysLock(), chSysUnlock(), chThdResume(), chThdSuspendTimeoutS(), MSG_OK, pipe_write(), pipe_t::reset, pipe_t::rtr, and pipe_t::wtr.

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size_t chPipeReadTimeout	(	pipe_t *	pp,
		uint8_t *	bp,
		size_t	n,
		sysinterval_t	timeout
	)

Pipe read with timeout.

The function reads data from a pipe into a buffer. The operation completes when the specified amount of data has been transferred or after the specified timeout or if the pipe has been reset.

Parameters

[in]	pp	the pointer to an initialized `pipe_t` object
[out]	bp	pointer to the data buffer
[in]	n	the number of bytes to be read, the value 0 is reserved
[in]	timeout	the number of ticks before the operation timeouts, the following special values are allowed: TIME_IMMEDIATE immediate timeout. TIME_INFINITE no timeout.