drivers/staging/lustre/lustre/obdclass/uuid.c

   1 /*
   2  * GPL HEADER START
   3  *
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License version 2 for more details (a copy is included
  14  * in the LICENSE file that accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * version 2 along with this program; If not, see
  18  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  19  *
  20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  21  * CA 95054 USA or visit www.sun.com if you need additional information or
  22  * have any questions.
  23  *
  24  * GPL HEADER END
  25  */
  26 /*
  27  * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
  28  * Use is subject to license terms.
  29  */
  30 /*
  31  * This file is part of Lustre, http://www.lustre.org/
  32  * Lustre is a trademark of Sun Microsystems, Inc.
  33  *
  34  * lustre/obdclass/uuid.c
  35  *
  36  * Public include file for the UUID library
  37  */
  38
  39 #define DEBUG_SUBSYSTEM S_CLASS
  40
  41 #include "../../include/linux/libcfs/libcfs.h"
  42
  43 #include <obd_support.h>
  44 #include <obd_class.h>
  45
  46
  47 static inline __u32 consume(int nob, __u8 **ptr)
  48 {
  49         __u32 value;
  50
  51         LASSERT(nob <= sizeof(value));
  52
  53         for (value = 0; nob > 0; --nob)
  54                 value = (value << 8) | *((*ptr)++);
  55         return value;
  56 }
  57
  58 #define CONSUME(val, ptr) (val) = consume(sizeof(val), (ptr))
  59
  60 static void uuid_unpack(class_uuid_t in, __u16 *uu, int nr)
  61 {
  62         __u8 *ptr = in;
  63
  64         LASSERT(nr * sizeof(*uu) == sizeof(class_uuid_t));
  65
  66         while (nr-- > 0)
  67                 CONSUME(uu[nr], &ptr);
  68 }
  69
  70 void class_uuid_unparse(class_uuid_t uu, struct obd_uuid *out)
  71 {
  72         /* uu as an array of __u16's */
  73         __u16 uuid[sizeof(class_uuid_t) / sizeof(__u16)];
  74
  75         CLASSERT(ARRAY_SIZE(uuid) == 8);
  76
  77         uuid_unpack(uu, uuid, ARRAY_SIZE(uuid));
  78         sprintf(out->uuid, "%04x%04x-%04x-%04x-%04x-%04x%04x%04x",
  79                 uuid[0], uuid[1], uuid[2], uuid[3],
  80                 uuid[4], uuid[5], uuid[6], uuid[7]);
  81 }
  82 EXPORT_SYMBOL(class_uuid_unparse);