lib/fsusage.c

   1 /* fsusage.c -- return space usage of mounted filesystems
   2    Copyright (C) 1991, 1992, 1996, 1998, 1999 Free Software Foundation, Inc.
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 2, or (at your option)
   7    any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program; if not, write to the Free Software Foundation,
  16    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  17
  18 #if HAVE_CONFIG_H
  19 # include <config.h>
  20 #endif
  21
  22 #if HAVE_INTTYPES_H
  23 # include <inttypes.h>
  24 #endif
  25 #include <sys/types.h>
  26 #include <sys/stat.h>
  27 #include "fsusage.h"
  28
  29 #if HAVE_LIMITS_H
  30 # include <limits.h>
  31 #endif
  32 #ifndef CHAR_BIT
  33 # define CHAR_BIT 8
  34 #endif
  35
  36 int statfs ();
  37
  38 #if HAVE_SYS_PARAM_H
  39 # include <sys/param.h>
  40 #endif
  41
  42 #if HAVE_SYS_MOUNT_H
  43 # include <sys/mount.h>
  44 #endif
  45
  46 #if HAVE_SYS_VFS_H
  47 # include <sys/vfs.h>
  48 #endif
  49
  50 #if HAVE_SYS_FS_S5PARAM_H       /* Fujitsu UXP/V */
  51 # include <sys/fs/s5param.h>
  52 #endif
  53
  54 #if defined (HAVE_SYS_FILSYS_H) && !defined (_CRAY)
  55 # include <sys/filsys.h>        /* SVR2 */
  56 #endif
  57
  58 #if HAVE_FCNTL_H
  59 # include <fcntl.h>
  60 #endif
  61
  62 #if HAVE_SYS_STATFS_H
  63 # include <sys/statfs.h>
  64 #endif
  65
  66 #if HAVE_DUSTAT_H               /* AIX PS/2 */
  67 # include <sys/dustat.h>
  68 #endif
  69
  70 #if HAVE_SYS_STATVFS_H          /* SVR4 */
  71 # include <sys/statvfs.h>
  72 int statvfs ();
  73 #endif
  74
  75 /* Many space usage primitives use all 1 bits to denote a value that is
  76    not applicable or unknown.  Propagate this information by returning
  77    a uintmax_t value that is all 1 bits if the argument is all 1 bits,
  78    even if the argument is unsigned and smaller than uintmax_t.  */
  79 #define PROPAGATE_ALL_ONES(x) ((x) == -1 ? (uintmax_t) -1 : (uintmax_t) (x))
  80
  81 /* Extract the top bit of X as an uintmax_t value.  */
  82 #define EXTRACT_TOP_BIT(x) ((x) \
  83                             & ((uintmax_t) 1 << (sizeof (x) * CHAR_BIT - 1)))
  84
  85 /* If a value is negative, many space usage primitives store it into an
  86    integer variable by assignment, even if the variable's type is unsigned.
  87    So, if a space usage variable X's top bit is set, convert X to the
  88    uintmax_t value V such that (- (uintmax_t) V) is the negative of
  89    the original value.  If X's top bit is clear, just yield X.
  90    Use PROPAGATE_TOP_BIT if the original value might be negative;
  91    otherwise, use PROPAGATE_ALL_ONES.  */
  92 #define PROPAGATE_TOP_BIT(x) ((x) | ~ (EXTRACT_TOP_BIT (x) - 1))
  93
  94 int safe_read ();
  95
  96 /* Fill in the fields of FSP with information about space usage for
  97    the filesystem on which PATH resides.
  98    DISK is the device on which PATH is mounted, for space-getting
  99    methods that need to know it.
 100    Return 0 if successful, -1 if not.  When returning -1, ensure that
 101    ERRNO is either a system error value, or zero if DISK is NULL
 102    on a system that requires a non-NULL value.  */
 103 int
 104 get_fs_usage (const char *path, const char *disk, struct fs_usage *fsp)
 105 {
 106 #ifdef STAT_STATFS3_OSF1
 107
 108   struct statfs fsd;
 109
 110   if (statfs (path, &fsd, sizeof (struct statfs)) != 0)
 111     return -1;
 112
 113   fsp->fsu_blocksize = PROPAGATE_ALL_ONES (fsd.f_fsize);
 114
 115 #endif /* STAT_STATFS3_OSF1 */
 116
 117 #ifdef STAT_STATFS2_FS_DATA     /* Ultrix */
 118
 119   struct fs_data fsd;
 120
 121   if (statfs (path, &fsd) != 1)
 122     return -1;
 123
 124   fsp->fsu_blocksize = 1024;
 125   fsp->fsu_blocks = PROPAGATE_ALL_ONES (fsd.fd_req.btot);
 126   fsp->fsu_bfree = PROPAGATE_ALL_ONES (fsd.fd_req.bfree);
 127   fsp->fsu_bavail = PROPAGATE_TOP_BIT (fsd.fd_req.bfreen);
 128   fsp->fsu_bavail_top_bit_set = EXTRACT_TOP_BIT (fsd.fd_req.bfreen) != 0;
 129   fsp->fsu_files = PROPAGATE_ALL_ONES (fsd.fd_req.gtot);
 130   fsp->fsu_ffree = PROPAGATE_ALL_ONES (fsd.fd_req.gfree);
 131
 132 #endif /* STAT_STATFS2_FS_DATA */
 133
 134 #ifdef STAT_READ_FILSYS         /* SVR2 */
 135 # ifndef SUPERBOFF
 136 #  define SUPERBOFF (SUPERB * 512)
 137 # endif
 138
 139   struct filsys fsd;
 140   int fd;
 141
 142   if (! disk)
 143     {
 144       errno = 0;
 145       return -1;
 146     }
 147
 148   fd = open (disk, O_RDONLY);
 149   if (fd < 0)
 150     return -1;
 151   lseek (fd, (off_t) SUPERBOFF, 0);
 152   if (safe_read (fd, (char *) &fsd, sizeof fsd) != sizeof fsd)
 153     {
 154       close (fd);
 155       return -1;
 156     }
 157   close (fd);
 158
 159   fsp->fsu_blocksize = (fsd.s_type == Fs2b ? 1024 : 512);
 160   fsp->fsu_blocks = PROPAGATE_ALL_ONES (fsd.s_fsize);
 161   fsp->fsu_bfree = PROPAGATE_ALL_ONES (fsd.s_tfree);
 162   fsp->fsu_bavail = PROPAGATE_TOP_BIT (fsd.s_tfree);
 163   fsp->fsu_bavail_top_bit_set = EXTRACT_TOP_BIT (fsd.s_tfree) != 0;
 164   fsp->fsu_files = (fsd.s_isize == -1
 165                     ? (uintmax_t) -1
 166                     : (fsd.s_isize - 2) * INOPB * (fsd.s_type == Fs2b ? 2 : 1));
 167   fsp->fsu_ffree = PROPAGATE_ALL_ONES (fsd.s_tinode);
 168
 169 #endif /* STAT_READ_FILSYS */
 170
 171 #ifdef STAT_STATFS2_BSIZE       /* 4.3BSD, SunOS 4, HP-UX, AIX */
 172
 173   struct statfs fsd;
 174
 175   if (statfs (path, &fsd) < 0)
 176     return -1;
 177
 178   fsp->fsu_blocksize = PROPAGATE_ALL_ONES (fsd.f_bsize);
 179
 180 # ifdef STATFS_TRUNCATES_BLOCK_COUNTS
 181
 182   /* In SunOS 4.1.2, 4.1.3, and 4.1.3_U1, the block counts in the
 183      struct statfs are truncated to 2GB.  These conditions detect that
 184      truncation, presumably without botching the 4.1.1 case, in which
 185      the values are not truncated.  The correct counts are stored in
 186      undocumented spare fields.  */
 187   if (fsd.f_blocks == 0x7fffffff / fsd.f_bsize && fsd.f_spare[0] > 0)
 188     {
 189       fsd.f_blocks = fsd.f_spare[0];
 190       fsd.f_bfree = fsd.f_spare[1];
 191       fsd.f_bavail = fsd.f_spare[2];
 192     }
 193 # endif /* STATFS_TRUNCATES_BLOCK_COUNTS */
 194
 195 #endif /* STAT_STATFS2_BSIZE */
 196
 197 #ifdef STAT_STATFS2_FSIZE       /* 4.4BSD */
 198
 199   struct statfs fsd;
 200
 201   if (statfs (path, &fsd) < 0)
 202     return -1;
 203
 204   fsp->fsu_blocksize = PROPAGATE_ALL_ONES (fsd.f_fsize);
 205
 206 #endif /* STAT_STATFS2_FSIZE */
 207
 208 #ifdef STAT_STATFS4             /* SVR3, Dynix, Irix, AIX */
 209
 210 # if !_AIX && !defined _SEQUENT_ && !defined DOLPHIN
 211 #  define f_bavail f_bfree
 212 # endif
 213
 214   struct statfs fsd;
 215
 216   if (statfs (path, &fsd, sizeof fsd, 0) < 0)
 217     return -1;
 218
 219   /* Empirically, the block counts on most SVR3 and SVR3-derived
 220      systems seem to always be in terms of 512-byte blocks,
 221      no matter what value f_bsize has.  */
 222 # if _AIX || defined(_CRAY)
 223    fsp->fsu_blocksize = PROPAGATE_ALL_ONES (fsd.f_bsize);
 224 # else
 225    fsp->fsu_blocksize = 512;
 226 # endif
 227
 228 #endif /* STAT_STATFS4 */
 229
 230 #ifdef STAT_STATVFS             /* SVR4 */
 231
 232   struct statvfs fsd;
 233
 234   if (statvfs (path, &fsd) < 0)
 235     return -1;
 236
 237   /* f_frsize isn't guaranteed to be supported.  */
 238   fsp->fsu_blocksize =
 239     PROPAGATE_ALL_ONES (fsd.f_frsize ? fsd.f_frsize : fsd.f_bsize);
 240
 241 #endif /* STAT_STATVFS */
 242
 243 #if !defined(STAT_STATFS2_FS_DATA) && !defined(STAT_READ_FILSYS)
 244                                 /* !Ultrix && !SVR2 */
 245
 246   fsp->fsu_blocks = PROPAGATE_ALL_ONES (fsd.f_blocks);
 247   fsp->fsu_bfree = PROPAGATE_ALL_ONES (fsd.f_bfree);
 248   fsp->fsu_bavail = PROPAGATE_TOP_BIT (fsd.f_bavail);
 249   fsp->fsu_bavail_top_bit_set = EXTRACT_TOP_BIT (fsd.f_bavail) != 0;
 250   fsp->fsu_files = PROPAGATE_ALL_ONES (fsd.f_files);
 251   fsp->fsu_ffree = PROPAGATE_ALL_ONES (fsd.f_ffree);
 252
 253 #endif /* not STAT_STATFS2_FS_DATA && not STAT_READ_FILSYS */
 254
 255   return 0;
 256 }
 257
 258 #if defined(_AIX) && defined(_I386)
 259 /* AIX PS/2 does not supply statfs.  */
 260
 261 int
 262 statfs (char *path, struct statfs *fsb)
 263 {
 264   struct stat stats;
 265   struct dustat fsd;
 266
 267   if (stat (path, &stats))
 268     return -1;
 269   if (dustat (stats.st_dev, 0, &fsd, sizeof (fsd)))
 270     return -1;
 271   fsb->f_type   = 0;
 272   fsb->f_bsize  = fsd.du_bsize;
 273   fsb->f_blocks = fsd.du_fsize - fsd.du_isize;
 274   fsb->f_bfree  = fsd.du_tfree;
 275   fsb->f_bavail = fsd.du_tfree;
 276   fsb->f_files  = (fsd.du_isize - 2) * fsd.du_inopb;
 277   fsb->f_ffree  = fsd.du_tinode;
 278   fsb->f_fsid.val[0] = fsd.du_site;
 279   fsb->f_fsid.val[1] = fsd.du_pckno;
 280   return 0;
 281 }
 282
 283 #endif /* _AIX && _I386 */