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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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