Be more systematic about conversion of on-disk formats in a endian/width

agnostic way.

Collapse the MBR and MBREXT methods into one file and make them endian/width
agnostic.

Sponsored by:	DARPA & NAI Labs.

1 files changed, 101 insertions, 0 deletions

diff --git a/sys/geom/geom_enc.c b/sys/geom/geom_enc.c
new file mode 100644
index 0000000..d711215
--- /dev/null
+++ b/sys/geom/geom_enc.c
@@ -0,0 +1,101 @@
+/*-
+ * Copyright (c) 2002 Poul-Henning Kamp
+ * Copyright (c) 2002 Networks Associates Technology, Inc.
+ * All rights reserved.
+ *
+ * This software was developed for the FreeBSD Project by Poul-Henning Kamp
+ * and NAI Labs, the Security Research Division of Network Associates, Inc.
+ * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
+ * DARPA CHATS research program.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The names of the authors may not be used to endorse or promote
+ *    products derived from this software without specific prior written
+ *    permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+/*
+ * This file contains routines to pack and unpack integerfields of varying
+ * width and endianess with.  Ideally the C language would have this built
+ * in but I guess Dennis and Brian forgot that back in the early 70ies.
+ *
+ * The function names are systematic: g_{enc|dec}_{be|le}%d
+ *	enc -> encode
+ *	dec -> decode
+ *	be -> big endian
+ *	le -> little endian
+ *	%d -> width in bytes
+ *
+ * Please keep the functions sorted:
+ *	decode before encode
+ *	big endian before little endian
+ *	small width before larger width
+ *	(this happens to be alphabetically)
+ */
+
+#include <sys/param.h>
+#ifdef _KERNEL
+#include <sys/malloc.h>
+#endif
+#include <geom/geom.h>
+
+uint32_t
+g_dec_be2(u_char *p)
+{
+
+	return((p[0] << 8) | p[1]);
+}
+
+uint32_t
+g_dec_be4(u_char *p)
+{
+
+	return((p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3]);
+}
+
+uint32_t
+g_dec_le2(u_char *p)
+{
+
+	return((p[1] << 8) | p[0]);
+}
+
+uint32_t
+g_dec_le4(u_char *p)
+{
+
+	return((p[3] << 24) | (p[2] << 16) | (p[1] << 8) | p[0]);
+}
+
+
+void
+g_enc_le4(u_char *p, uint32_t u)
+{
+
+	p[0] = u & 0xff;
+	p[1] = (u >> 8) & 0xff;
+	p[2] = (u >> 16) & 0xff;
+	p[3] = (u >> 24) & 0xff;
+}
+