fs/intermezzo/intermezzo_lib.h

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  * Copyright (C) 2001 Cluster File Systems, Inc. <braam@clusterfs.com>
   5  *
   6  *   This file is part of InterMezzo, http://www.inter-mezzo.org.
   7  *
   8  *   InterMezzo is free software; you can redistribute it and/or
   9  *   modify it under the terms of version 2 of the GNU General Public
  10  *   License as published by the Free Software Foundation.
  11  *
  12  *   InterMezzo is distributed in the hope that it will be useful,
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *   GNU General Public License for more details.
  16  *
  17  *   You should have received a copy of the GNU General Public License
  18  *   along with InterMezzo; if not, write to the Free Software
  19  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20  *
  21  * Data structures unpacking/packing macros & inlines
  22  *
  23  */
  24
  25 #ifndef _INTERMEZZO_LIB_H
  26 #define _INTERMEZZO_LIB_H
  27
  28 #ifdef __KERNEL__
  29 # include <linux/types.h>
  30 #else
  31 # include <string.h>
  32 # include <sys/types.h>
  33 #endif
  34
  35 static inline int size_round (int val)
  36 {
  37         return (val + 3) & (~0x3);
  38 }
  39
  40 static inline int size_round0(int val)
  41 {
  42         if (!val)
  43                 return 0;
  44         return (val + 1 + 3) & (~0x3);
  45 }
  46
  47 static inline size_t round_strlen(char *fset)
  48 {
  49         return size_round(strlen(fset) + 1);
  50 }
  51
  52 #ifdef __KERNEL__
  53 # define NTOH__u32(var) le32_to_cpu(var)
  54 # define NTOH__u64(var) le64_to_cpu(var)
  55 # define HTON__u32(var) cpu_to_le32(var)
  56 # define HTON__u64(var) cpu_to_le64(var)
  57 #else
  58 # include <glib.h>
  59 # define NTOH__u32(var) GUINT32_FROM_LE(var)
  60 # define NTOH__u64(var) GUINT64_FROM_LE(var)
  61 # define HTON__u32(var) GUINT32_TO_LE(var)
  62 # define HTON__u64(var) GUINT64_TO_LE(var)
  63 #endif
  64
  65 /*
  66  * copy sizeof(type) bytes from pointer to var and move ptr forward.
  67  * return EFAULT if pointer goes beyond end
  68  */
  69 #define UNLOGV(var,type,ptr,end)                \
  70 do {                                            \
  71         var = *(type *)ptr;                     \
  72         ptr += sizeof(type);                    \
  73         if (ptr > end )                         \
  74                 return -EFAULT;                 \
  75 } while (0)
  76
  77 /* the following two macros convert to little endian */
  78 /* type MUST be __u32 or __u64 */
  79 #define LUNLOGV(var,type,ptr,end)               \
  80 do {                                            \
  81         var = NTOH##type(*(type *)ptr);         \
  82         ptr += sizeof(type);                    \
  83         if (ptr > end )                         \
  84                 return -EFAULT;                 \
  85 } while (0)
  86
  87 /* now log values */
  88 #define LOGV(var,type,ptr)                      \
  89 do {                                            \
  90         *((type *)ptr) = var;                   \
  91         ptr += sizeof(type);                    \
  92 } while (0)
  93
  94 /* and in network order */
  95 #define LLOGV(var,type,ptr)                     \
  96 do {                                            \
  97         *((type *)ptr) = HTON##type(var);       \
  98         ptr += sizeof(type);                    \
  99 } while (0)
 100
 101
 102 /*
 103  * set var to point at (type *)ptr, move ptr forward with sizeof(type)
 104  * return from function with EFAULT if ptr goes beyond end
 105  */
 106 #define UNLOGP(var,type,ptr,end)                \
 107 do {                                            \
 108         var = (type *)ptr;                      \
 109         ptr += sizeof(type);                    \
 110         if (ptr > end )                         \
 111                 return -EFAULT;                 \
 112 } while (0)
 113
 114 #define LOGP(var,type,ptr)                      \
 115 do {                                            \
 116         memcpy(ptr, var, sizeof(type));         \
 117         ptr += sizeof(type);                    \
 118 } while (0)
 119
 120 /*
 121  * set var to point at (char *)ptr, move ptr forward by size_round(len);
 122  * return from function with EFAULT if ptr goes beyond end
 123  */
 124 #define UNLOGL(var,type,len,ptr,end)                    \
 125 do {                                                    \
 126         if (len == 0)                                   \
 127                 var = (type *)0;                        \
 128         else {                                          \
 129                 var = (type *)ptr;                      \
 130                 ptr += size_round(len * sizeof(type));  \
 131         }                                               \
 132         if (ptr > end )                                 \
 133                 return -EFAULT;                         \
 134 } while (0)
 135
 136 #define UNLOGL0(var,type,len,ptr,end)                           \
 137 do {                                                            \
 138         UNLOGL(var,type,len+1,ptr,end);                         \
 139         if ( *((char *)ptr - size_round(len+1) + len) != '\0')  \
 140                         return -EFAULT;                         \
 141 } while (0)
 142
 143 #define LOGL(var,len,ptr)                               \
 144 do {                                                    \
 145         size_t __fill = size_round(len);                \
 146         /* Prevent data leakage. */                     \
 147         if (__fill > 0)                                 \
 148                 memset((char *)ptr, 0, __fill);         \
 149         memcpy((char *)ptr, (const char *)var, len);    \
 150         ptr += __fill;                                  \
 151 } while (0)
 152
 153 #define LOGL0(var,len,ptr)                              \
 154 do {                                                    \
 155         if (!len) break;                                \
 156         memcpy((char *)ptr, (const char *)var, len);    \
 157         *((char *)(ptr) + len) = 0;                     \
 158         ptr += size_round(len + 1);                     \
 159 } while (0)
 160
 161 #endif /* _INTERMEZZO_LIB_H */
 162