usr/src/lib/libast/common/port/iblocks.c

   1 /***********************************************************************
   2 *                                                                      *
   3 *               This software is part of the ast package               *
   4 *          Copyright (c) 1985-2010 AT&T Intellectual Property          *
   5 *                      and is licensed under the                       *
   6 *                  Common Public License, Version 1.0                  *
   7 *                    by AT&T Intellectual Property                     *
   8 *                                                                      *
   9 *                A copy of the License is available at                 *
  10 *            http://www.opensource.org/licenses/cpl1.0.txt             *
  11 *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
  12 *                                                                      *
  13 *              Information and Software Systems Research               *
  14 *                            AT&T Research                             *
  15 *                           Florham Park NJ                            *
  16 *                                                                      *
  17 *                 Glenn Fowler <gsf@research.att.com>                  *
  18 *                  David Korn <dgk@research.att.com>                   *
  19 *                   Phong Vo <kpv@research.att.com>                    *
  20 *                                                                      *
  21 ***********************************************************************/
  22 #pragma prototyped
  23 /*
  24  * aux function for <ls.h> iblocks() macro
  25  *
  26  * return number of blocks, including indirect block count
  27  * given stat info
  28  *
  29  * mail gsf@research.att.com when you figure out the stat.st_blocks units
  30  * until then we assume LS_BLOCKSIZE (512)
  31  */
  32
  33 #include <ast.h>
  34 #if _AIX /* XXX */
  35 #undef  major
  36 #undef  minor
  37 #undef  makedev
  38 #endif
  39 #include <ast_param.h>
  40 #include <ls.h>
  41
  42 #if !_mem_st_blocks_stat
  43
  44 #ifndef B_DIRECT
  45 #define B_DIRECT        10
  46 #endif
  47
  48 #ifdef BITFS
  49
  50 #define B_SIZE          BSIZE(st->st_dev)
  51 #define B_INDIRECT      NINDIR(st->st_dev)
  52
  53 #else
  54
  55 #ifdef BSIZE
  56 #define B_SIZE          BSIZE
  57 #else
  58 #define B_SIZE          1024
  59 #endif
  60
  61 #ifdef NINDIR
  62 #define B_INDIRECT      NINDIR
  63 #else
  64 #define B_INDIRECT      128
  65 #endif
  66
  67 #endif
  68
  69 #endif
  70
  71 off_t
  72 _iblocks(register struct stat* st)
  73 {
  74 #if _mem_st_blocks_stat
  75
  76         return (st->st_blocks <= 0 || st->st_size <= 0) ? 0 : st->st_blocks;
  77
  78 #else
  79         unsigned long   b;
  80         unsigned long   t;
  81
  82         t = b = (st->st_size + B_SIZE - 1) / B_SIZE;
  83         if ((b -= B_DIRECT) > 0)
  84         {
  85                 t += (b - 1) / B_INDIRECT + 1;
  86                 if ((b -= B_INDIRECT) > 0)
  87                 {
  88                         t += (b - 1) / (B_INDIRECT * B_INDIRECT) + 1;
  89                         if (b > B_INDIRECT * B_INDIRECT)
  90                                 t++;
  91                 }
  92         }
  93         return t * B_SIZE / LS_BLOCKSIZE;
  94 #endif
  95 }