/*
* Copyright (C) 2007 Michael Brown <mbrown@fensystems.co.uk>.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <string.h>
#include <errno.h>
#include <gpxe/xfer.h>
/** @file
*
* Data transfer interfaces
*
*/
/**
* Close data transfer interface
*
* @v xfer Data transfer interface
* @v rc Reason for close
*/
void xfer_close ( struct xfer_interface *xfer, int rc ) {
struct xfer_interface *dest = xfer_get_dest ( xfer );
dest->op->close ( dest, rc );
xfer_unplug ( xfer );
xfer_put ( dest );
}
/**
* Send redirection event
*
* @v xfer Data transfer interface
* @v type New location type
* @v args Remaining arguments depend upon location type
* @ret rc Return status code
*/
int xfer_vredirect ( struct xfer_interface *xfer, int type, va_list args ) {
struct xfer_interface *dest = xfer_get_dest ( xfer );
int rc;
rc = dest->op->vredirect ( dest, type, args );
xfer_put ( dest );
return rc;
}
/**
* Send redirection event
*
* @v xfer Data transfer interface
* @v type New location type
* @v ... Remaining arguments depend upon location type
* @ret rc Return status code
*/
int xfer_redirect ( struct xfer_interface *xfer, int type, ... ) {
va_list args;
int rc;
va_start ( args, type );
rc = xfer_vredirect ( xfer, type, args );
va_end ( args );
return rc;
}
/**
* Request data
*
* @v xfer Data transfer interface
* @v offset Offset to new position
* @v whence Basis for new position
* @v len Length of requested data
* @ret rc Return status code
*/
int xfer_request ( struct xfer_interface *xfer, off_t offset, int whence,
size_t len ) {
struct xfer_interface *dest = xfer_get_dest ( xfer );
int rc;
rc = dest->op->request ( dest, offset, whence, len );
xfer_put ( dest );
return rc;
}
/**
* Request all data
*
* @v xfer Data transfer interface
* @ret rc Return status code
*/
int xfer_request_all ( struct xfer_interface *xfer ) {
return xfer_request ( xfer, 0, SEEK_SET, ~( ( size_t ) 0 ) );
}
/**
* Seek to position
*
* @v xfer Data transfer interface
* @v offset Offset to new position
* @v whence Basis for new position
* @ret rc Return status code
*/
int xfer_seek ( struct xfer_interface *xfer, off_t offset, int whence ) {
struct xfer_interface *dest = xfer_get_dest ( xfer );
int rc;
rc = dest->op->seek ( dest, offset, whence );
xfer_put ( dest );
return rc;
}
/**
* Allocate I/O buffer
*
* @v xfer Data transfer interface
* @v len I/O buffer payload length
* @ret iobuf I/O buffer
*/
struct io_buffer * xfer_alloc_iob ( struct xfer_interface *xfer, size_t len ) {
struct xfer_interface *dest = xfer_get_dest ( xfer );
struct io_buffer *iobuf;
iobuf = dest->op->alloc_iob ( dest, len );
xfer_put ( dest );
return iobuf;
}
/**
* Deliver datagram
*
* @v xfer Data transfer interface
* @v iobuf Datagram I/O buffer
* @ret rc Return status code
*/
int xfer_deliver_iob ( struct xfer_interface *xfer, struct io_buffer *iobuf ) {
struct xfer_interface *dest = xfer_get_dest ( xfer );
int rc;
rc = dest->op->deliver_iob ( dest, iobuf );
xfer_put ( dest );
return rc;
}
/**
* Deliver datagram as raw data
*
* @v xfer Data transfer interface
* @v iobuf Datagram I/O buffer
* @ret rc Return status code
*/
int xfer_deliver_raw ( struct xfer_interface *xfer,
const void *data, size_t len ) {
struct xfer_interface *dest = xfer_get_dest ( xfer );
int rc;
rc = dest->op->deliver_raw ( dest, data, len );
xfer_put ( dest );
return rc;
}
/****************************************************************************
*
* Helper methods
*
* These functions are designed to be used as methods in the
* xfer_interface_operations table.
*
*/
/**
* Ignore close() event
*
* @v xfer Data transfer interface
* @v rc Reason for close
*/
void ignore_xfer_close ( struct xfer_interface *xfer __unused,
int rc __unused ) {
/* Nothing to do */
}
/**
* Ignore vredirect() event
*
* @v xfer Data transfer interface
* @v type New location type
* @v args Remaining arguments depend upon location type
* @ret rc Return status code
*/
int ignore_xfer_vredirect ( struct xfer_interface *xfer __unused,
int type __unused, va_list args __unused ) {
return 0;
}
/**
* Ignore request() event
*
* @v xfer Data transfer interface
* @v offset Offset to new position
* @v whence Basis for new position
* @v len Length of requested data
* @ret rc Return status code
*/
int ignore_xfer_request ( struct xfer_interface *xfer __unused,
off_t offset __unused, int whence __unused,
size_t len __unused ) {
return 0;
}
/**
* Ignore seek() event
*
* @v xfer Data transfer interface
* @v offset Offset to new position
* @v whence Basis for new position
* @ret rc Return status code
*/
int ignore_xfer_seek ( struct xfer_interface *xfer __unused,
off_t offset __unused, int whence __unused ) {
return 0;
}
/**
* Allocate I/O buffer
*
* @v xfer Data transfer interface
* @v len I/O buffer payload length
* @ret iobuf I/O buffer
*/
struct io_buffer *
default_xfer_alloc_iob ( struct xfer_interface *xfer __unused, size_t len ) {
return alloc_iob ( len );
}
/**
* Deliver datagram as raw data
*
* @v xfer Data transfer interface
* @v iobuf Datagram I/O buffer
* @ret rc Return status code
*
* This function is intended to be used as the deliver() method for
* data transfer interfaces that prefer to handle raw data.
*/
int xfer_deliver_as_raw ( struct xfer_interface *xfer,
struct io_buffer *iobuf ) {
int rc;
rc = xfer->op->deliver_raw ( xfer, iobuf->data, iob_len ( iobuf ) );
free_iob ( iobuf );
return rc;
}
/**
* Deliver datagram as I/O buffer
*
* @v xfer Data transfer interface
* @v data Data buffer
* @v len Length of data buffer
* @ret rc Return status code
*
* This function is intended to be used as the deliver_raw() method
* for data transfer interfaces that prefer to handle I/O buffers.
*/
int xfer_deliver_as_iob ( struct xfer_interface *xfer,
const void *data, size_t len ) {
struct io_buffer *iobuf;
iobuf = xfer->op->alloc_iob ( xfer, len );
if ( ! iobuf )
return -ENOMEM;
memcpy ( iob_put ( iobuf, len ), data, len );
return xfer->op->deliver_iob ( xfer, iobuf );
}
/**
* Ignore datagram as raw data event
*
* @v xfer Data transfer interface
* @v data Data buffer
* @v len Length of data buffer
* @ret rc Return status code
*/
int ignore_xfer_deliver_raw ( struct xfer_interface *xfer,
const void *data __unused, size_t len ) {
DBGC ( xfer, "XFER %p %zd bytes delivered %s\n", xfer, len,
( ( xfer == &null_xfer ) ?
"before connection" : "after termination" ) );
return 0;
}
/** Null data transfer interface operations */
struct xfer_interface_operations null_xfer_ops = {
.close = ignore_xfer_close,
.vredirect = ignore_xfer_vredirect,
.request = ignore_xfer_request,
.seek = ignore_xfer_seek,
.alloc_iob = default_xfer_alloc_iob,
.deliver_iob = xfer_deliver_as_raw,
.deliver_raw = ignore_xfer_deliver_raw,
};
/**
* Null data transfer interface
*
* This is the interface to which data transfer interfaces are
* connected when unplugged. It will never generate messages, and
* will silently absorb all received messages.
*/
struct xfer_interface null_xfer = {
.intf = {
.dest = &null_xfer.intf,
.refcnt = NULL,
},
.op = &null_xfer_ops,
};
