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 "replace.h"
  21 #include "lib/util/samba_util.h"
  22 #include "system/filesys.h"
  23
  24 /**
  25  * @file
  26  * @brief Utility functions for getting the amount of free disk space
  27  */
  28
  29 /* Return the number of TOSIZE-byte blocks used by
  30    BLOCKS FROMSIZE-byte blocks, rounding away from zero.
  31 */
  32 static uint64_t adjust_blocks(uint64_t blocks, uint64_t fromsize, uint64_t tosize)
  33 {
  34         if (fromsize == tosize) { /* e.g., from 512 to 512 */
  35                 return blocks;
  36         } else if (fromsize > tosize) { /* e.g., from 2048 to 512 */
  37                 return blocks * (fromsize / tosize);
  38         } else { /* e.g., from 256 to 512 */
  39                 /* Protect against broken filesystems... */
  40                 if (fromsize == 0) {
  41                         fromsize = tosize;
  42                 }
  43                 return (blocks + 1) / (tosize / fromsize);
  44         }
  45 }
  46
  47 /**
  48  * Retrieve amount of free disk space.
  49  * this does all of the system specific guff to get the free disk space.
  50  * It is derived from code in the GNU fileutils package, but has been
  51  * considerably mangled for use here
  52  *
  53  * results are returned in *dfree and *dsize, in 512 byte units
  54 */
  55 _PUBLIC_ int sys_fsusage(const char *path, uint64_t *dfree, uint64_t *dsize)
  56 {
  57 #ifdef STAT_STATFS3_OSF1
  58 #define CONVERT_BLOCKS(B) adjust_blocks ((uint64_t)(B), (uint64_t)fsd.f_fsize, (uint64_t)512)
  59         struct statfs fsd;
  60
  61         if (statfs (path, &fsd, sizeof (struct statfs)) != 0)
  62                 return -1;
  63 #endif /* STAT_STATFS3_OSF1 */
  64
  65 #ifdef STAT_STATFS2_FS_DATA     /* Ultrix */
  66 #define CONVERT_BLOCKS(B) adjust_blocks ((uint64_t)(B), (uint64_t)1024, (uint64_t)512)
  67         struct fs_data fsd;
  68
  69         if (statfs (path, &fsd) != 1)
  70                 return -1;
  71
  72         (*dsize) = CONVERT_BLOCKS (fsd.fd_req.btot);
  73         (*dfree) = CONVERT_BLOCKS (fsd.fd_req.bfreen);
  74 #endif /* STAT_STATFS2_FS_DATA */
  75
  76 #ifdef STAT_STATFS2_BSIZE       /* 4.3BSD, SunOS 4, HP-UX, AIX */
  77 #define CONVERT_BLOCKS(B) adjust_blocks ((uint64_t)(B), (uint64_t)fsd.f_bsize, (uint64_t)512)
  78         struct statfs fsd;
  79
  80         if (statfs (path, &fsd) < 0)
  81                 return -1;
  82
  83 #ifdef STATFS_TRUNCATES_BLOCK_COUNTS
  84         /* In SunOS 4.1.2, 4.1.3, and 4.1.3_U1, the block counts in the
  85            struct statfs are truncated to 2GB.  These conditions detect that
  86            truncation, presumably without botching the 4.1.1 case, in which
  87            the values are not truncated.  The correct counts are stored in
  88            undocumented spare fields.  */
  89         if (fsd.f_blocks == 0x1fffff && fsd.f_spare[0] > 0) {
  90                 fsd.f_blocks = fsd.f_spare[0];
  91                 fsd.f_bfree = fsd.f_spare[1];
  92                 fsd.f_bavail = fsd.f_spare[2];
  93         }
  94 #endif /* STATFS_TRUNCATES_BLOCK_COUNTS */
  95 #endif /* STAT_STATFS2_BSIZE */
  96
  97
  98 #ifdef STAT_STATFS2_FSIZE       /* 4.4BSD */
  99 #define CONVERT_BLOCKS(B) adjust_blocks ((uint64_t)(B), (uint64_t)fsd.f_fsize, (uint64_t)512)
 100
 101         struct statfs fsd;
 102
 103         if (statfs (path, &fsd) < 0)
 104                 return -1;
 105 #endif /* STAT_STATFS2_FSIZE */
 106
 107 #ifdef STAT_STATFS4             /* SVR3, Dynix, Irix, AIX */
 108 # if _AIX || defined(_CRAY)
 109 #  define CONVERT_BLOCKS(B) adjust_blocks ((uint64_t)(B), (uint64_t)fsd.f_bsize, (uint64_t)512)
 110 #  ifdef _CRAY
 111 #   define f_bavail f_bfree
 112 #  endif
 113 # else
 114 #  define CONVERT_BLOCKS(B) ((uint64_t)B)
 115 #  ifndef _SEQUENT_             /* _SEQUENT_ is DYNIX/ptx */
 116 #   ifndef DOLPHIN              /* DOLPHIN 3.8.alfa/7.18 has f_bavail */
 117 #    define f_bavail f_bfree
 118 #   endif
 119 #  endif
 120 # endif
 121
 122         struct statfs fsd;
 123
 124         if (statfs (path, &fsd, sizeof fsd, 0) < 0)
 125                 return -1;
 126         /* Empirically, the block counts on most SVR3 and SVR3-derived
 127            systems seem to always be in terms of 512-byte blocks,
 128            no matter what value f_bsize has.  */
 129
 130 #endif /* STAT_STATFS4 */
 131
 132 #if defined(STAT_STATVFS)               /* SVR4 */
 133 #ifdef HAVE_FRSIZE
 134 # define CONVERT_BLOCKS(B) \
 135         adjust_blocks ((uint64_t)(B), fsd.f_frsize ? (uint64_t)fsd.f_frsize : (uint64_t)fsd.f_bsize, (uint64_t)512)
 136 #else
 137 # define CONVERT_BLOCKS(B) \
 138         adjust_blocks ((uint64_t)(B), (uint64_t)fsd.f_bsize, (uint64_t)512)
 139 #endif
 140
 141         struct statvfs fsd;
 142         if (statvfs(path, &fsd) < 0) return -1;
 143
 144         /* f_frsize isn't guaranteed to be supported.  */
 145
 146 #endif /* STAT_STATVFS */
 147
 148 #ifndef CONVERT_BLOCKS
 149         /* we don't have any dfree code! */
 150         return -1;
 151 #else
 152 #if !defined(STAT_STATFS2_FS_DATA)
 153         /* !Ultrix */
 154         (*dsize) = CONVERT_BLOCKS (fsd.f_blocks);
 155         (*dfree) = CONVERT_BLOCKS (fsd.f_bavail);
 156 #endif /* not STAT_STATFS2_FS_DATA */
 157 #endif
 158
 159         return 0;
 160 }