lib/util/fsusage.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    functions to calculate the free disk space
   4    Copyright (C) Andrew Tridgell 1998-2000
   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 as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "includes.h"
  21 #include "system/filesys.h"
  22
  23 /**
  24  * @file
  25  * @brief Utility functions for getting the amount of free disk space
  26  */
  27
  28 /* Return the number of TOSIZE-byte blocks used by
  29    BLOCKS FROMSIZE-byte blocks, rounding away from zero.
  30 */
  31 static uint64_t adjust_blocks(uint64_t blocks, uint64_t fromsize, uint64_t tosize)
  32 {
  33         if (fromsize == tosize) /* e.g., from 512 to 512 */
  34                 return blocks;
  35         else if (fromsize > tosize)     /* e.g., from 2048 to 512 */
  36                 return blocks * (fromsize / tosize);
  37         else                            /* e.g., from 256 to 512 */
  38                 return (blocks + 1) / (tosize / fromsize);
  39 }
  40
  41 /**
  42  * Retrieve amount of free disk space.
  43  * this does all of the system specific guff to get the free disk space.
  44  * It is derived from code in the GNU fileutils package, but has been
  45  * considerably mangled for use here
  46  *
  47  * results are returned in *dfree and *dsize, in 512 byte units
  48 */
  49 _PUBLIC_ int sys_fsusage(const char *path, uint64_t *dfree, uint64_t *dsize)
  50 {
  51 #ifdef STAT_STATFS3_OSF1
  52 #define CONVERT_BLOCKS(B) adjust_blocks ((uint64_t)(B), (uint64_t)fsd.f_fsize, (uint64_t)512)
  53         struct statfs fsd;
  54
  55         if (statfs (path, &fsd, sizeof (struct statfs)) != 0)
  56                 return -1;
  57 #endif /* STAT_STATFS3_OSF1 */
  58
  59 #ifdef STAT_STATFS2_FS_DATA     /* Ultrix */
  60 #define CONVERT_BLOCKS(B) adjust_blocks ((uint64_t)(B), (uint64_t)1024, (uint64_t)512)
  61         struct fs_data fsd;
  62
  63         if (statfs (path, &fsd) != 1)
  64                 return -1;
  65
  66         (*dsize) = CONVERT_BLOCKS (fsd.fd_req.btot);
  67         (*dfree) = CONVERT_BLOCKS (fsd.fd_req.bfreen);
  68 #endif /* STAT_STATFS2_FS_DATA */
  69
  70 #ifdef STAT_STATFS2_BSIZE       /* 4.3BSD, SunOS 4, HP-UX, AIX */
  71 #define CONVERT_BLOCKS(B) adjust_blocks ((uint64_t)(B), (uint64_t)fsd.f_bsize, (uint64_t)512)
  72         struct statfs fsd;
  73
  74         if (statfs (path, &fsd) < 0)
  75                 return -1;
  76
  77 #ifdef STATFS_TRUNCATES_BLOCK_COUNTS
  78         /* In SunOS 4.1.2, 4.1.3, and 4.1.3_U1, the block counts in the
  79            struct statfs are truncated to 2GB.  These conditions detect that
  80            truncation, presumably without botching the 4.1.1 case, in which
  81            the values are not truncated.  The correct counts are stored in
  82            undocumented spare fields.  */
  83         if (fsd.f_blocks == 0x1fffff && fsd.f_spare[0] > 0) {
  84                 fsd.f_blocks = fsd.f_spare[0];
  85                 fsd.f_bfree = fsd.f_spare[1];
  86                 fsd.f_bavail = fsd.f_spare[2];
  87         }
  88 #endif /* STATFS_TRUNCATES_BLOCK_COUNTS */
  89 #endif /* STAT_STATFS2_BSIZE */
  90
  91
  92 #ifdef STAT_STATFS2_FSIZE       /* 4.4BSD */
  93 #define CONVERT_BLOCKS(B) adjust_blocks ((uint64_t)(B), (uint64_t)fsd.f_fsize, (uint64_t)512)
  94
  95         struct statfs fsd;
  96
  97         if (statfs (path, &fsd) < 0)
  98                 return -1;
  99 #endif /* STAT_STATFS2_FSIZE */
 100
 101 #ifdef STAT_STATFS4             /* SVR3, Dynix, Irix, AIX */
 102 # if _AIX || defined(_CRAY)
 103 #  define CONVERT_BLOCKS(B) adjust_blocks ((uint64_t)(B), (uint64_t)fsd.f_bsize, (uint64_t)512)
 104 #  ifdef _CRAY
 105 #   define f_bavail f_bfree
 106 #  endif
 107 # else
 108 #  define CONVERT_BLOCKS(B) ((uint64_t)B)
 109 #  ifndef _SEQUENT_             /* _SEQUENT_ is DYNIX/ptx */
 110 #   ifndef DOLPHIN              /* DOLPHIN 3.8.alfa/7.18 has f_bavail */
 111 #    define f_bavail f_bfree
 112 #   endif
 113 #  endif
 114 # endif
 115
 116         struct statfs fsd;
 117
 118         if (statfs (path, &fsd, sizeof fsd, 0) < 0)
 119                 return -1;
 120         /* Empirically, the block counts on most SVR3 and SVR3-derived
 121            systems seem to always be in terms of 512-byte blocks,
 122            no matter what value f_bsize has.  */
 123
 124 #endif /* STAT_STATFS4 */
 125
 126 #if defined(STAT_STATVFS) || defined(STAT_STATVFS64)            /* SVR4 */
 127 # define CONVERT_BLOCKS(B) \
 128         adjust_blocks ((uint64_t)(B), fsd.f_frsize ? (uint64_t)fsd.f_frsize : (uint64_t)fsd.f_bsize, (uint64_t)512)
 129
 130 #ifdef STAT_STATVFS64
 131         struct statvfs64 fsd;
 132         if (statvfs64(path, &fsd) < 0) return -1;
 133 #else
 134         struct statvfs fsd;
 135         if (statvfs(path, &fsd) < 0) return -1;
 136 #endif
 137
 138         /* f_frsize isn't guaranteed to be supported.  */
 139
 140 #endif /* STAT_STATVFS */
 141
 142 #ifndef CONVERT_BLOCKS
 143         /* we don't have any dfree code! */
 144         return -1;
 145 #else
 146 #if !defined(STAT_STATFS2_FS_DATA)
 147         /* !Ultrix */
 148         (*dsize) = CONVERT_BLOCKS (fsd.f_blocks);
 149         (*dfree) = CONVERT_BLOCKS (fsd.f_bavail);
 150 #endif /* not STAT_STATFS2_FS_DATA */
 151 #endif
 152
 153         return 0;
 154 }