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/*
* Copyright (C) 2012 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 (at your option) 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., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*/
FILE_LICENCE ( GPL2_OR_LATER );
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <ipxe/xfer.h>
#include <ipxe/iobuf.h>
#include <ipxe/xferbuf.h>
/** @file
*
* Data transfer buffer
*
*/
/**
* Finish using data transfer buffer
*
* @v xferbuf Data transfer buffer
*/
void xferbuf_done ( struct xfer_buffer *xferbuf ) {
free ( xferbuf->data );
xferbuf->data = NULL;
xferbuf->len = 0;
xferbuf->pos = 0;
}
/**
* Ensure that data transfer buffer is large enough for the specified size
*
* @v xferbuf Data transfer buffer
* @v len Required minimum size
* @ret rc Return status code
*/
static int xferbuf_ensure_size ( struct xfer_buffer *xferbuf, size_t len ) {
void *new_data;
/* If buffer is already large enough, do nothing */
if ( len <= xferbuf->len )
return 0;
/* Extend buffer */
new_data = realloc ( xferbuf->data, len );
if ( ! new_data ) {
DBGC ( xferbuf, "XFERBUF %p could not extend buffer to "
"%zd bytes\n", xferbuf, len );
return -ENOSPC;
}
xferbuf->data = new_data;
xferbuf->len = len;
return 0;
}
/**
* Add received data to data transfer buffer
*
* @v xferbuf Data transfer buffer
* @v iobuf I/O buffer
* @v meta Data transfer metadata
* @ret rc Return status code
*/
int xferbuf_deliver ( struct xfer_buffer *xferbuf, struct io_buffer *iobuf,
struct xfer_metadata *meta ) {
size_t len;
size_t max;
int rc;
/* Calculate new buffer position */
if ( meta->flags & XFER_FL_ABS_OFFSET )
xferbuf->pos = 0;
xferbuf->pos += meta->offset;
/* Ensure that we have enough buffer space for this data */
len = iob_len ( iobuf );
max = ( xferbuf->pos + len );
if ( ( rc = xferbuf_ensure_size ( xferbuf, max ) ) != 0 )
goto done;
/* Copy data to buffer */
memcpy ( ( xferbuf->data + xferbuf->pos ), iobuf->data, len );
/* Update current buffer position */
xferbuf->pos += len;
done:
free_iob ( iobuf );
return rc;
}
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