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Diffstat (limited to 'debian/grub-extras/disabled/gpxe/src/net/iobpad.c')
-rw-r--r--debian/grub-extras/disabled/gpxe/src/net/iobpad.c68
1 files changed, 68 insertions, 0 deletions
diff --git a/debian/grub-extras/disabled/gpxe/src/net/iobpad.c b/debian/grub-extras/disabled/gpxe/src/net/iobpad.c
new file mode 100644
index 0000000..cbae221
--- /dev/null
+++ b/debian/grub-extras/disabled/gpxe/src/net/iobpad.c
@@ -0,0 +1,68 @@
+/*
+ * 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.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+/**
+ * @file
+ *
+ * I/O buffer padding
+ *
+ */
+
+#include <string.h>
+#include <gpxe/iobuf.h>
+
+/**
+ * Pad I/O buffer
+ *
+ * @v iobuf I/O buffer
+ * @v min_len Minimum length
+ *
+ * This function pads and aligns I/O buffers, for devices that
+ * aren't capable of padding in hardware, or that require specific
+ * alignment in TX buffers. The packet data will end up aligned to a
+ * multiple of @c IOB_ALIGN.
+ *
+ * @c min_len must not exceed @v IOB_ZLEN.
+ */
+void iob_pad ( struct io_buffer *iobuf, size_t min_len ) {
+ void *data;
+ size_t len;
+ size_t headroom;
+ signed int pad_len;
+
+ assert ( min_len <= IOB_ZLEN );
+
+ /* Move packet data to start of I/O buffer. This will both
+ * align the data (since I/O buffers are aligned to
+ * IOB_ALIGN) and give us sufficient space for the
+ * zero-padding
+ */
+ data = iobuf->data;
+ len = iob_len ( iobuf );
+ headroom = iob_headroom ( iobuf );
+ iob_push ( iobuf, headroom );
+ memmove ( iobuf->data, data, len );
+ iob_unput ( iobuf, headroom );
+
+ /* Pad to minimum packet length */
+ pad_len = ( min_len - iob_len ( iobuf ) );
+ if ( pad_len > 0 )
+ memset ( iob_put ( iobuf, pad_len ), 0, pad_len );
+}