tx.c File Reference

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Detailed Description

Network TX drivers.

This file is the "ancestor" class of all TX drivers, and therefore only implements general routines that are mostly common, as well as provides type-checked entry points for dynamically dispatched routines, such as tx_write().

Author:

Raphael Manfredi

Date:

2002-2005

#include "common.h"
#include "tx.h"
#include "nodes.h"
#include "lib/walloc.h"
#include "lib/override.h"

Data Structures
struct	tx_close_arg
	Argument for tx_close_next(). More...
Defines
#define	TX_INIT(o, a)   ((o)->ops->init((o), (a)))
#define	TX_DESTROY(o)   ((o)->ops->destroy((o)))
#define	TX_WRITE(o, d, l)   ((o)->ops->write((o), (d), (l)))
#define	TX_WRITEV(o, i, c)   ((o)->ops->writev((o), (i), (c)))
#define	TX_SENDTO(o, t, d, l)   ((o)->ops->sendto((o), (t), (d), (l)))
#define	TX_ENABLE(o)   ((o)->ops->enable((o)))
#define	TX_DISABLE(o)   ((o)->ops->disable((o)))
#define	TX_PENDING(o)   ((o)->ops->pending((o)))
#define	TX_BIO_SOURCE(o)   ((o)->ops->bio_source((o)))
#define	TX_FLUSH(o)   ((o)->ops->flush((o)))
#define	TX_SHUTDOWN(o)   ((o)->ops->shutdown((o)))
#define	TX_CLOSE(o, c, a)   ((o)->ops->close((o), (c), (a)))
Functions
	RCSID ("$Id:tx.c, v 1.21 2005/11/30 16:43:41 rmanfredi Exp $")
txdrv_t *	tx_make (gpointer owner, gnet_host_t *host, const struct txdrv_ops *ops, gpointer args)
	Create a new network driver, equipped with the `ops' operations and initialize its specific parameters by calling the init routine with `args'.
void	tx_attached (txdrv_t *tx, txdrv_t *utx)
	Called when an upper driver (utx) is attached on top of us.
txdrv_t *	tx_make_above (txdrv_t *ltx, const struct txdrv_ops *ops, gpointer args)
	Createion routine for a driver to be stacked above specified lower `ltx'.
void	tx_shutdown (txdrv_t *tx)
	Shutdown stack, disallowing further writes.
void	tx_deep_free (txdrv_t *tx)
	Dispose of the driver resources, recursively.
void	tx_free (txdrv_t *tx)
	Dispose of the driver resources, asynchronously.
void	tx_collect (void)
	Collect freed stacks.
ssize_t	tx_write (txdrv_t *tx, gpointer data, size_t len)
	Write `len' bytes starting at `data'.
ssize_t	tx_writev (txdrv_t *tx, struct iovec *iov, gint iovcnt)
	Write I/O vector.
ssize_t	tx_sendto (txdrv_t *tx, gnet_host_t *to, gpointer data, size_t len)
	Send buffer datagram to specified destination `to'.
void	tx_srv_register (txdrv_t *tx, tx_service_t srv_fn, gpointer srv_arg)
	Register service routine from upper TX layer.
void	tx_srv_enable (txdrv_t *tx)
	Record that upper layer wants its service routine enabled.
void	tx_srv_disable (txdrv_t *tx)
	Record that upper layer wants its service routine disabled.
size_t	tx_pending (txdrv_t *tx)
txdrv_t *	tx_deep_bottom (txdrv_t *tx)
void	tx_eager_mode (txdrv_t *tx, gboolean on)
	Set stack in "eager" mode: in that mode, servicing is always enabled in the whole stack, meaning the bottom layer always invokes the queue service routines whenever it can accept more data.
bio_source *	tx_bio_source (txdrv_t *tx)
	The I/O source of the lowest layer (link) that physically sends the information.
void	tx_flush (txdrv_t *tx)
	Request that data be sent immediately.
gboolean	tx_has_error (txdrv_t *tx)
void	tx_close_next (txdrv_t *tx, gpointer arg)
	Callback invoked when a layer in the TX stack was closed, i.e.
void	tx_close (txdrv_t *tx, tx_closed_t cb, gpointer arg)
	Close the transmission by ensuring each layer properly finishes sending its data.
void	tx_close_noop (txdrv_t *tx, tx_closed_t cb, gpointer arg)
	No-operation closing routine for layers that don't need anything special.
ssize_t	tx_no_write (txdrv_t *unused_tx, gpointer unused_data, size_t unused_len)
	The write() operation is forbidden.
ssize_t	tx_no_writev (txdrv_t *unused_tx, struct iovec *unused_iov, gint unused_iovcnt)
	The writev() operation is forbidden.
ssize_t	tx_no_sendto (txdrv_t *unused_tx, gnet_host_t *unused_to, gpointer unused_data, size_t unused_len)
	The sendto() operation is forbidden.
bio_source *	tx_no_source (txdrv_t *unused_tx)
	No I/O source can be fetched from this layer.
Variables
GSList *	tx_freed = NULL
	To guarantee that destruction of the stack always happens asynchronously with respect to the caller (i.e.

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Define Documentation

#define TX_BIO_SOURCE (  o   )     ((o)->ops->bio_source((o)))

#define TX_CLOSE (  o, c, a   )     ((o)->ops->close((o), (c), (a)))

#define TX_DESTROY (  o   )     ((o)->ops->destroy((o)))

#define TX_DISABLE (  o   )     ((o)->ops->disable((o)))

#define TX_ENABLE (  o   )     ((o)->ops->enable((o)))

#define TX_FLUSH (  o   )     ((o)->ops->flush((o)))

#define TX_INIT (  o, a   )     ((o)->ops->init((o), (a)))

#define TX_PENDING (  o   )     ((o)->ops->pending((o)))

#define TX_SENDTO (  o, t, d, l   )     ((o)->ops->sendto((o), (t), (d), (l)))

#define TX_SHUTDOWN (  o   )     ((o)->ops->shutdown((o)))

#define TX_WRITE (  o, d, l   )     ((o)->ops->write((o), (d), (l)))

#define TX_WRITEV (  o, i, c   )     ((o)->ops->writev((o), (i), (c)))

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Function Documentation

RCSID (  "$Id:tx.  c, v 1.21 2005/11/30 16:43:41 rmanfredi Exp $"  )

void tx_attached (  txdrv_t *  tx, txdrv_t *  utx )  [static]

Called when an upper driver (utx) is attached on top of us.

struct bio_source* tx_bio_source (  txdrv_t *  tx  )

The I/O source of the lowest layer (link) that physically sends the information.

void tx_close (  txdrv_t *  tx, tx_closed_t  cb, gpointer  arg )

Close the transmission by ensuring each layer properly finishes sending its data. When the whole stack is done, invoke the specified callback.

void tx_close_next (  txdrv_t *  tx, gpointer  arg )  [static]

Callback invoked when a layer in the TX stack was closed, i.e. has no longer any buffered data. Proceed to the next layer if any, otherwise invoke the user callback.

void tx_close_noop (  txdrv_t *  tx, tx_closed_t  cb, gpointer  arg )

No-operation closing routine for layers that don't need anything special.

void tx_collect (  void   )

Collect freed stacks.

txdrv_t* tx_deep_bottom (  txdrv_t *  tx  )  [static]

Returns: the driver at the bottom of the stack.

void tx_deep_free (  txdrv_t *  tx  )  [static]

Dispose of the driver resources, recursively.

void tx_eager_mode (  txdrv_t *  tx, gboolean  on )

Set stack in "eager" mode: in that mode, servicing is always enabled in the whole stack, meaning the bottom layer always invokes the queue service routines whenever it can accept more data. This mode is appropriate when the data to send is already generated or easily computed on demand and the limiting factor is the output bandwidth.

void tx_flush (  txdrv_t *  tx  )

Request that data be sent immediately.

void tx_free (  txdrv_t *  tx  )

Dispose of the driver resources, asynchronously. It must be called on the top layer only.

gboolean tx_has_error (  txdrv_t *  tx  )

Returns: TRUE if there is an error reported by any layer underneath.

txdrv_t* tx_make (  gpointer  owner, gnet_host_t *  host, const struct txdrv_ops *  ops, gpointer  args )

Create a new network driver, equipped with the `ops' operations and initialize its specific parameters by calling the init routine with `args'. Returns: NULL if there is an initialization problem.

txdrv_t* tx_make_above (  txdrv_t *  ltx, const struct txdrv_ops *  ops, gpointer  args )

Createion routine for a driver to be stacked above specified lower `ltx'. Returns: NULL if there is an initialization problem.

ssize_t tx_no_sendto (  txdrv_t *  unused_tx, gnet_host_t *  unused_to, gpointer  unused_data, size_t  unused_len )

The sendto() operation is forbidden.

struct bio_source* tx_no_source (  txdrv_t *  unused_tx  )

No I/O source can be fetched from this layer.

ssize_t tx_no_write (  txdrv_t *  unused_tx, gpointer  unused_data, size_t  unused_len )

The write() operation is forbidden.

ssize_t tx_no_writev (  txdrv_t *  unused_tx, struct iovec *  unused_iov, gint  unused_iovcnt )

The writev() operation is forbidden.

size_t tx_pending (  txdrv_t *  tx  )

Returns: amount of data pending in the whole stack.

ssize_t tx_sendto (  txdrv_t *  tx, gnet_host_t *  to, gpointer  data, size_t  len )

Send buffer datagram to specified destination `to'. Returns: amount of bytes written, or -1 on error with errno set.

void tx_shutdown (  txdrv_t *  tx  )

Shutdown stack, disallowing further writes.

void tx_srv_disable (  txdrv_t *  tx  )

Record that upper layer wants its service routine disabled.

void tx_srv_enable (  txdrv_t *  tx  )

Record that upper layer wants its service routine enabled.

void tx_srv_register (  txdrv_t *  tx, tx_service_t  srv_fn, gpointer  srv_arg )

Register service routine from upper TX layer.

ssize_t tx_write (  txdrv_t *  tx, gpointer  data, size_t  len )

Write `len' bytes starting at `data'. Returns: the amount of bytes written, or -1 with errno set on error.

ssize_t tx_writev (  txdrv_t *  tx, struct iovec *  iov, gint  iovcnt )

Write I/O vector. Returns: amount of bytes written, or -1 on error with errno set.

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Variable Documentation

GSList* tx_freed = NULL [static]

To guarantee that destruction of the stack always happens asynchronously with respect to the caller (i.e. it is not happening in the same calling stack), freed stacks are remembered and periodically collected.

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