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                 /* Protect against broken filesystems... */
  39                 if (fromsize == 0) {
  40                         fromsize = tosize;
  41                 }
  42                 return (blocks + 1) / (tosize / fromsize);
  43         }
  44 }
  45
  46 /**
  47  * Retrieve amount of free disk space.
  48  * this does all of the system specific guff to get the free disk space.
  49  * It is derived from code in the GNU fileutils package, but has been
  50  * considerably mangled for use here
  51  *
  52  * results are returned in *dfree and *dsize, in 512 byte units
  53 */
  54 _PUBLIC_ int sys_fsusage(const char *path, uint64_t *dfree, uint64_t *dsize)
  55 {
  56 #ifdef STAT_STATFS3_OSF1
  57 #define CONVERT_BLOCKS(B) adjust_blocks ((uint64_t)(B), (uint64_t)fsd.f_fsize, (uint64_t)512)
  58         struct statfs fsd;
  59
  60         if (statfs (path, &fsd, sizeof (struct statfs)) != 0)
  61                 return -1;
  62 #endif /* STAT_STATFS3_OSF1 */
  63
  64 #ifdef STAT_STATFS2_FS_DATA     /* Ultrix */
  65 #define CONVERT_BLOCKS(B) adjust_blocks ((uint64_t)(B), (uint64_t)1024, (uint64_t)512)
  66         struct fs_data fsd;
  67
  68         if (statfs (path, &fsd) != 1)
  69                 return -1;
  70
  71         (*dsize) = CONVERT_BLOCKS (fsd.fd_req.btot);
  72         (*dfree) = CONVERT_BLOCKS (fsd.fd_req.bfreen);
  73 #endif /* STAT_STATFS2_FS_DATA */
  74
  75 #ifdef STAT_STATFS2_BSIZE       /* 4.3BSD, SunOS 4, HP-UX, AIX */
  76 #define CONVERT_BLOCKS(B) adjust_blocks ((uint64_t)(B), (uint64_t)fsd.f_bsize, (uint64_t)512)
  77         struct statfs fsd;
  78
  79         if (statfs (path, &fsd) < 0)
  80                 return -1;
  81
  82 #ifdef STATFS_TRUNCATES_BLOCK_COUNTS
  83         /* In SunOS 4.1.2, 4.1.3, and 4.1.3_U1, the block counts in the
  84            struct statfs are truncated to 2GB.  These conditions detect that
  85            truncation, presumably without botching the 4.1.1 case, in which
  86            the values are not truncated.  The correct counts are stored in
  87            undocumented spare fields.  */
  88         if (fsd.f_blocks == 0x1fffff && fsd.f_spare[0] > 0) {
  89                 fsd.f_blocks = fsd.f_spare[0];
  90                 fsd.f_bfree = fsd.f_spare[1];
  91                 fsd.f_bavail = fsd.f_spare[2];
  92         }
  93 #endif /* STATFS_TRUNCATES_BLOCK_COUNTS */
  94 #endif /* STAT_STATFS2_BSIZE */
  95
  96
  97 #ifdef STAT_STATFS2_FSIZE       /* 4.4BSD */
  98 #define CONVERT_BLOCKS(B) adjust_blocks ((uint64_t)(B), (uint64_t)fsd.f_fsize, (uint64_t)512)
  99
 100         struct statfs fsd;
 101
 102         if (statfs (path, &fsd) < 0)
 103                 return -1;
 104 #endif /* STAT_STATFS2_FSIZE */
 105
 106 #ifdef STAT_STATFS4             /* SVR3, Dynix, Irix, AIX */
 107 # if _AIX || defined(_CRAY)
 108 #  define CONVERT_BLOCKS(B) adjust_blocks ((uint64_t)(B), (uint64_t)fsd.f_bsize, (uint64_t)512)
 109 #  ifdef _CRAY
 110 #   define f_bavail f_bfree
 111 #  endif
 112 # else
 113 #  define CONVERT_BLOCKS(B) ((uint64_t)B)
 114 #  ifndef _SEQUENT_             /* _SEQUENT_ is DYNIX/ptx */
 115 #   ifndef DOLPHIN              /* DOLPHIN 3.8.alfa/7.18 has f_bavail */
 116 #    define f_bavail f_bfree
 117 #   endif
 118 #  endif
 119 # endif
 120
 121         struct statfs fsd;
 122
 123         if (statfs (path, &fsd, sizeof fsd, 0) < 0)
 124                 return -1;
 125         /* Empirically, the block counts on most SVR3 and SVR3-derived
 126            systems seem to always be in terms of 512-byte blocks,
 127            no matter what value f_bsize has.  */
 128
 129 #endif /* STAT_STATFS4 */
 130
 131 #if defined(STAT_STATVFS) || defined(STAT_STATVFS64)            /* SVR4 */
 132 #ifdef HAVE_FRSIZE
 133 # define CONVERT_BLOCKS(B) \
 134         adjust_blocks ((uint64_t)(B), fsd.f_frsize ? (uint64_t)fsd.f_frsize : (uint64_t)fsd.f_bsize, (uint64_t)512)
 135 #else
 136 # define CONVERT_BLOCKS(B) \
 137         adjust_blocks ((uint64_t)(B), (uint64_t)fsd.f_bsize, (uint64_t)512)
 138 #endif
 139
 140 #ifdef STAT_STATVFS64
 141         struct statvfs64 fsd;
 142         if (statvfs64(path, &fsd) < 0) return -1;
 143 #else
 144         struct statvfs fsd;
 145         if (statvfs(path, &fsd) < 0) return -1;
 146 #endif
 147
 148         /* f_frsize isn't guaranteed to be supported.  */
 149
 150 #endif /* STAT_STATVFS */
 151
 152 #ifndef CONVERT_BLOCKS
 153         /* we don't have any dfree code! */
 154         return -1;
 155 #else
 156 #if !defined(STAT_STATFS2_FS_DATA)
 157         /* !Ultrix */
 158         (*dsize) = CONVERT_BLOCKS (fsd.f_blocks);
 159         (*dfree) = CONVERT_BLOCKS (fsd.f_bavail);
 160 #endif /* not STAT_STATFS2_FS_DATA */
 161 #endif
 162
 163         return 0;
 164 }