#include <I_Cache.h>

Inherited by CacheVC, and ClusterVConnectionBase.

Collaboration diagram for CacheVConnection:

Public Member Functions
VIO *	do_io_read (Continuation c, int64_t nbytes, MIOBuffer buf)=0
	Read data from the VConnection.
virtual VIO *	do_io_pread (Continuation c, int64_t nbytes, MIOBuffer buf, int64_t offset)=0
VIO *	do_io_write (Continuation c, int64_t nbytes, IOBufferReader buf, bool owner=false)=0
	Write data to the VConnection.
void	do_io_close (int lerrno=-1)=0
	Indicate that the VConnection is no longer needed.
void	reenable (VIO *avio)=0
void	reenable_re (VIO *avio)=0
void	do_io_shutdown (ShutdownHowTo_t howto)
	Terminate one or both directions of the VConnection.
virtual int	get_header (void *ptr, int len)=0
virtual int	set_header (void *ptr, int len)=0
virtual int	get_single_data (void *ptr, int len)=0
virtual bool	is_ram_cache_hit () const =0
virtual bool	set_disk_io_priority (int priority)=0
virtual int	get_disk_io_priority ()=0
virtual bool	set_pin_in_cache (time_t t)=0
virtual time_t	get_pin_in_cache ()=0
virtual int64_t	get_object_size ()=0
virtual bool	is_pread_capable ()=0
	Test if the VC can support pread.
	CacheVConnection ()

Detailed Description

Definition at line 202 of file I_Cache.h.

Constructor & Destructor Documentation

CacheVConnection::CacheVConnection ( )

Definition at line 2938 of file Cache.cc.

Member Function Documentation

void CacheVConnection::do_io_close ( int lerrno = -1 ) [pure virtual]

Indicate that the VConnection is no longer needed.

Once the state machine has finished using this VConnection, it must call this function to indicate that the VConnection can be deallocated. After a close has been called, the VConnection and underlying processor must not send any more events related to this VConnection to the state machine. Likeswise, the state machine must not access the VConnection or any VIOs obtained from it after calling this method.

Parameters:

lerrno

indicates where a close is a normal close or an abort. The difference between a normal close and an abort depends on the underlying type of the VConnection.

Implements VConnection.

Implemented in CacheVC, ClusterVConnectionBase, and ClusterVConnection.

Referenced by CacheTestSM::event_handler().

virtual VIO* CacheVConnection::do_io_pread	(	Continuation *	c,
		int64_t	nbytes,
		MIOBuffer *	buf,
		int64_t	offset
	)			`[pure virtual]`

Implemented in CacheVC, and ClusterVConnectionBase.

VIO* CacheVConnection::do_io_read	(	Continuation *	c,
		int64_t	nbytes,
		MIOBuffer *	buf
	)			`[pure virtual]`

Read data from the VConnection.

Called by a state machine to read data from the VConnection. Processors implementing read functionality take out lock, put new bytes on the buffer and call the continuation back before releasing the lock in order to enable the state machine to handle transfer schemes where the end of a given transaction is marked by a special character (ie: NNTP).

Possible Event Codes

On the callback to the continuation, the VConnection may use on of the following values for the event code:

Event code	Meaning
VC_EVENT_READ_READY	Data has been added to the buffer or the buffer is full
VC_EVENT_READ_COMPLETE	The amount of data indicated by 'nbytes' has been read into the buffer
VC_EVENT_EOS	The stream being read from has been shutdown
VC_EVENT_ERROR	An error occurred during the read

Parameters:

	c	Continuation to be called back with events.
	nbytes	Number of bytes to read. If unknown, nbytes must be set to INT64_MAX.
	buf	buffer to read into.

Returns:: VIO representing the scheduled IO operation.

Implements VConnection.

Implemented in CacheVC, ClusterVConnectionBase, and ClusterVConnection.

Referenced by CacheTestSM::open_read_callout().

void CacheVConnection::do_io_shutdown ( ShutdownHowTo_t howto ) [inline, virtual]

Terminate one or both directions of the VConnection.

Indicates that one or both sides of the VConnection should be terminated. After this call is issued, no further I/O can be done on the specified direction of the connection. The processor must not send any further events (including timeout events) to the state machine, and the state machine must not use any VIOs from a shutdown direction of the connection. Even if both sides of a connection are shutdown, the state machine must still call do_io_close() when it wishes the VConnection to be deallocated.

Possible howto values

Value	Meaning
IO_SHUTDOWN_READ	Indicates that this VConnection should not generate any more read events
IO_SHUTDOWN_WRITE	Indicates that this VConnection should not generate any more write events
IO_SHUTDOWN_READWRITE	Indicates that this VConnection should not generate any more read nor write events

Parameters:

howto

Specifies which direction of the VConnection to shutdown.

Implements VConnection.

Reimplemented in ClusterVConnectionBase.

Definition at line 210 of file I_Cache.h.

References ink_assert.

VIO* CacheVConnection::do_io_write	(	Continuation *	c,
		int64_t	nbytes,
		IOBufferReader *	buf,
		bool	owner = `false`
	)			`[pure virtual]`

Write data to the VConnection.

This method is called by a state machine to write data to the VConnection.

Possible Event Codes

On the callback to the continuation, the VConnection may use on of the following event codes:

Event code	Meaning
VC_EVENT_WRITE_READY	Data was written from the reader or there are no bytes available for the reader to write.
VC_EVENT_WRITE_COMPLETE	The amount of data indicated by 'nbytes' has been written to the VConnection
VC_EVENT_INACTIVITY_TIMEOUT	No activity was performed for a certain period.
VC_EVENT_ACTIVE_TIMEOUT	Write operation continued beyond a time limit.
VC_EVENT_ERROR	An error occurred during the write

Parameters:

	c	Continuation to be called back with events.
	nbytes	Number of bytes to write. If unknown, nbytes must be set to INT64_MAX.
	buf	Reader whose data is to be read from.
	owner