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-rw-r--r--debian/grub-extras/disabled/gpxe/src/core/iobuf.c96
1 files changed, 96 insertions, 0 deletions
diff --git a/debian/grub-extras/disabled/gpxe/src/core/iobuf.c b/debian/grub-extras/disabled/gpxe/src/core/iobuf.c
new file mode 100644
index 0000000..1ce7890
--- /dev/null
+++ b/debian/grub-extras/disabled/gpxe/src/core/iobuf.c
@@ -0,0 +1,96 @@
+/*
+ * Copyright (C) 2006 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.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <stdint.h>
+#include <errno.h>
+#include <gpxe/malloc.h>
+#include <gpxe/iobuf.h>
+
+/** @file
+ *
+ * I/O buffers
+ *
+ */
+
+/**
+ * Allocate I/O buffer
+ *
+ * @v len Required length of buffer
+ * @ret iobuf I/O buffer, or NULL if none available
+ *
+ * The I/O buffer will be physically aligned to a multiple of
+ * @c IOBUF_SIZE.
+ */
+struct io_buffer * alloc_iob ( size_t len ) {
+ struct io_buffer *iobuf = NULL;
+ void *data;
+
+ /* Pad to minimum length */
+ if ( len < IOB_ZLEN )
+ len = IOB_ZLEN;
+
+ /* Align buffer length */
+ len = ( len + __alignof__( *iobuf ) - 1 ) &
+ ~( __alignof__( *iobuf ) - 1 );
+
+ /* Allocate memory for buffer plus descriptor */
+ data = malloc_dma ( len + sizeof ( *iobuf ), IOB_ALIGN );
+ if ( ! data )
+ return NULL;
+
+ iobuf = ( struct io_buffer * ) ( data + len );
+ iobuf->head = iobuf->data = iobuf->tail = data;
+ iobuf->end = iobuf;
+ return iobuf;
+}
+
+/**
+ * Free I/O buffer
+ *
+ * @v iobuf I/O buffer
+ */
+void free_iob ( struct io_buffer *iobuf ) {
+ if ( iobuf ) {
+ assert ( iobuf->head <= iobuf->data );
+ assert ( iobuf->data <= iobuf->tail );
+ assert ( iobuf->tail <= iobuf->end );
+ free_dma ( iobuf->head,
+ ( iobuf->end - iobuf->head ) + sizeof ( *iobuf ) );
+ }
+}
+
+/**
+ * Ensure I/O buffer has sufficient headroom
+ *
+ * @v iobuf I/O buffer
+ * @v len Required headroom
+ *
+ * This function currently only checks for the required headroom; it
+ * does not reallocate the I/O buffer if required. If we ever have a
+ * code path that requires this functionality, it's a fairly trivial
+ * change to make.
+ */
+int iob_ensure_headroom ( struct io_buffer *iobuf, size_t len ) {
+
+ if ( iob_headroom ( iobuf ) >= len )
+ return 0;
+ return -ENOBUFS;
+}
+