1 /* fsusage.c -- return space usage of mounted file systems
3 Copyright (C) 1991-1992, 1996, 1998-1999, 2002-2006, 2009-2016 Free Software
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.
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.
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/>. */
24 #include <sys/types.h>
26 #if STAT_STATVFS || STAT_STATVFS64 /* POSIX 1003.1-2001 (and later) with XSI */
27 # include <sys/statvfs.h>
29 /* Don't include backward-compatibility files unless they're needed.
30 Eventually we'd like to remove all this cruft. */
33 # include <sys/stat.h>
35 # include <sys/param.h>
38 # include <sys/mount.h>
43 # if HAVE_SYS_FS_S5PARAM_H /* Fujitsu UXP/V */
44 # include <sys/fs/s5param.h>
46 # if defined HAVE_SYS_FILSYS_H && !defined _CRAY
47 # include <sys/filsys.h> /* SVR2 */
49 # if HAVE_SYS_STATFS_H
50 # include <sys/statfs.h>
52 # if HAVE_DUSTAT_H /* AIX PS/2 */
53 # include <sys/dustat.h>
55 # include "full-read.h"
58 /* Many space usage primitives use all 1 bits to denote a value that is
59 not applicable or unknown. Propagate this information by returning
60 a uintmax_t value that is all 1 bits if X is all 1 bits, even if X
61 is unsigned and narrower than uintmax_t. */
62 #define PROPAGATE_ALL_ONES(x) \
63 ((sizeof (x) < sizeof (uintmax_t) \
64 && (~ (x) == (sizeof (x) < sizeof (int) \
65 ? - (1 << (sizeof (x) * CHAR_BIT)) \
67 ? UINTMAX_MAX : (uintmax_t) (x))
69 /* Extract the top bit of X as an uintmax_t value. */
70 #define EXTRACT_TOP_BIT(x) ((x) \
71 & ((uintmax_t) 1 << (sizeof (x) * CHAR_BIT - 1)))
73 /* If a value is negative, many space usage primitives store it into an
74 integer variable by assignment, even if the variable's type is unsigned.
75 So, if a space usage variable X's top bit is set, convert X to the
76 uintmax_t value V such that (- (uintmax_t) V) is the negative of
77 the original value. If X's top bit is clear, just yield X.
78 Use PROPAGATE_TOP_BIT if the original value might be negative;
79 otherwise, use PROPAGATE_ALL_ONES. */
80 #define PROPAGATE_TOP_BIT(x) ((x) | ~ (EXTRACT_TOP_BIT (x) - 1))
83 /* Return true if statvfs works. This is false for statvfs on systems
84 with GNU libc on Linux kernels before 2.6.36, which stats all
85 preceding entries in /proc/mounts; that makes df hang if even one
86 of the corresponding file systems is hard-mounted but not available. */
87 # if ! (__linux__ && (__GLIBC__ || __UCLIBC__))
88 /* The FRSIZE fallback is not required in this case. */
89 # undef STAT_STATFS2_FRSIZE
90 static int statvfs_works (void) { return 1; }
92 # include <string.h> /* for strverscmp */
93 # include <sys/utsname.h>
94 # include <sys/statfs.h>
95 # define STAT_STATFS2_BSIZE 1
100 static int statvfs_works_cache = -1;
102 if (statvfs_works_cache < 0)
103 statvfs_works_cache = (uname (&name) == 0
104 && 0 <= strverscmp (name.release, "2.6.36"));
105 return statvfs_works_cache;
111 /* Fill in the fields of FSP with information about space usage for
112 the file system on which FILE resides.
113 DISK is the device on which FILE is mounted, for space-getting
114 methods that need to know it.
115 Return 0 if successful, -1 if not. When returning -1, ensure that
116 ERRNO is either a system error value, or zero if DISK is NULL
117 on a system that requires a non-NULL value. */
119 get_fs_usage (char const *file, char const *disk, struct fs_usage *fsp)
121 #ifdef STAT_STATVFS /* POSIX, except pre-2.6.36 glibc/Linux */
123 if (statvfs_works ())
127 if (statvfs (file, &vfsd) < 0)
130 /* f_frsize isn't guaranteed to be supported. */
131 fsp->fsu_blocksize = (vfsd.f_frsize
132 ? PROPAGATE_ALL_ONES (vfsd.f_frsize)
133 : PROPAGATE_ALL_ONES (vfsd.f_bsize));
135 fsp->fsu_blocks = PROPAGATE_ALL_ONES (vfsd.f_blocks);
136 fsp->fsu_bfree = PROPAGATE_ALL_ONES (vfsd.f_bfree);
137 fsp->fsu_bavail = PROPAGATE_TOP_BIT (vfsd.f_bavail);
138 fsp->fsu_bavail_top_bit_set = EXTRACT_TOP_BIT (vfsd.f_bavail) != 0;
139 fsp->fsu_files = PROPAGATE_ALL_ONES (vfsd.f_files);
140 fsp->fsu_ffree = PROPAGATE_ALL_ONES (vfsd.f_ffree);
146 #if defined STAT_STATVFS64 /* AIX */
148 struct statvfs64 fsd;
150 if (statvfs64 (file, &fsd) < 0)
153 /* f_frsize isn't guaranteed to be supported. */
154 fsp->fsu_blocksize = (fsd.f_frsize
155 ? PROPAGATE_ALL_ONES (fsd.f_frsize)
156 : PROPAGATE_ALL_ONES (fsd.f_bsize));
158 #elif defined STAT_STATFS2_FS_DATA /* Ultrix */
162 if (statfs (file, &fsd) != 1)
165 fsp->fsu_blocksize = 1024;
166 fsp->fsu_blocks = PROPAGATE_ALL_ONES (fsd.fd_req.btot);
167 fsp->fsu_bfree = PROPAGATE_ALL_ONES (fsd.fd_req.bfree);
168 fsp->fsu_bavail = PROPAGATE_TOP_BIT (fsd.fd_req.bfreen);
169 fsp->fsu_bavail_top_bit_set = EXTRACT_TOP_BIT (fsd.fd_req.bfreen) != 0;
170 fsp->fsu_files = PROPAGATE_ALL_ONES (fsd.fd_req.gtot);
171 fsp->fsu_ffree = PROPAGATE_ALL_ONES (fsd.fd_req.gfree);
173 #elif defined STAT_READ_FILSYS /* SVR2 */
175 # define SUPERBOFF (SUPERB * 512)
187 fd = open (disk, O_RDONLY);
190 lseek (fd, (off_t) SUPERBOFF, 0);
191 if (full_read (fd, (char *) &fsd, sizeof fsd) != sizeof fsd)
198 fsp->fsu_blocksize = (fsd.s_type == Fs2b ? 1024 : 512);
199 fsp->fsu_blocks = PROPAGATE_ALL_ONES (fsd.s_fsize);
200 fsp->fsu_bfree = PROPAGATE_ALL_ONES (fsd.s_tfree);
201 fsp->fsu_bavail = PROPAGATE_TOP_BIT (fsd.s_tfree);
202 fsp->fsu_bavail_top_bit_set = EXTRACT_TOP_BIT (fsd.s_tfree) != 0;
203 fsp->fsu_files = (fsd.s_isize == -1
205 : (fsd.s_isize - 2) * INOPB * (fsd.s_type == Fs2b ? 2 : 1));
206 fsp->fsu_ffree = PROPAGATE_ALL_ONES (fsd.s_tinode);
208 #elif defined STAT_STATFS3_OSF1 /* OSF/1 */
212 if (statfs (file, &fsd, sizeof (struct statfs)) != 0)
215 fsp->fsu_blocksize = PROPAGATE_ALL_ONES (fsd.f_fsize);
217 #elif defined STAT_STATFS2_FRSIZE /* 2.6 < glibc/Linux < 2.6.36 */
221 if (statfs (file, &fsd) < 0)
224 fsp->fsu_blocksize = PROPAGATE_ALL_ONES (fsd.f_frsize);
226 #elif defined STAT_STATFS2_BSIZE /* glibc/Linux < 2.6, 4.3BSD, SunOS 4, \
227 Mac OS X < 10.4, FreeBSD < 5.0, \
228 NetBSD < 3.0, OpenBSD < 4.4 */
232 if (statfs (file, &fsd) < 0)
235 fsp->fsu_blocksize = PROPAGATE_ALL_ONES (fsd.f_bsize);
237 # ifdef STATFS_TRUNCATES_BLOCK_COUNTS
239 /* In SunOS 4.1.2, 4.1.3, and 4.1.3_U1, the block counts in the
240 struct statfs are truncated to 2GB. These conditions detect that
241 truncation, presumably without botching the 4.1.1 case, in which
242 the values are not truncated. The correct counts are stored in
243 undocumented spare fields. */
244 if (fsd.f_blocks == 0x7fffffff / fsd.f_bsize && fsd.f_spare[0] > 0)
246 fsd.f_blocks = fsd.f_spare[0];
247 fsd.f_bfree = fsd.f_spare[1];
248 fsd.f_bavail = fsd.f_spare[2];
250 # endif /* STATFS_TRUNCATES_BLOCK_COUNTS */
252 #elif defined STAT_STATFS2_FSIZE /* 4.4BSD and older NetBSD */
256 if (statfs (file, &fsd) < 0)
259 fsp->fsu_blocksize = PROPAGATE_ALL_ONES (fsd.f_fsize);
261 #elif defined STAT_STATFS4 /* SVR3, Dynix, old Irix, old AIX, \
264 # if !_AIX && !defined _SEQUENT_ && !defined DOLPHIN
265 # define f_bavail f_bfree
270 if (statfs (file, &fsd, sizeof fsd, 0) < 0)
273 /* Empirically, the block counts on most SVR3 and SVR3-derived
274 systems seem to always be in terms of 512-byte blocks,
275 no matter what value f_bsize has. */
276 # if _AIX || defined _CRAY
277 fsp->fsu_blocksize = PROPAGATE_ALL_ONES (fsd.f_bsize);
279 fsp->fsu_blocksize = 512;
284 #if (defined STAT_STATVFS64 || defined STAT_STATFS3_OSF1 \
285 || defined STAT_STATFS2_FRSIZE || defined STAT_STATFS2_BSIZE \
286 || defined STAT_STATFS2_FSIZE || defined STAT_STATFS4)
288 fsp->fsu_blocks = PROPAGATE_ALL_ONES (fsd.f_blocks);
289 fsp->fsu_bfree = PROPAGATE_ALL_ONES (fsd.f_bfree);
290 fsp->fsu_bavail = PROPAGATE_TOP_BIT (fsd.f_bavail);
291 fsp->fsu_bavail_top_bit_set = EXTRACT_TOP_BIT (fsd.f_bavail) != 0;
292 fsp->fsu_files = PROPAGATE_ALL_ONES (fsd.f_files);
293 fsp->fsu_ffree = PROPAGATE_ALL_ONES (fsd.f_ffree);
297 (void) disk; /* avoid argument-unused warning */
301 #if defined _AIX && defined _I386
302 /* AIX PS/2 does not supply statfs. */
305 statfs (char *file, struct statfs *fsb)
310 if (stat (file, &stats) != 0)
312 if (dustat (stats.st_dev, 0, &fsd, sizeof (fsd)))
315 fsb->f_bsize = fsd.du_bsize;
316 fsb->f_blocks = fsd.du_fsize - fsd.du_isize;
317 fsb->f_bfree = fsd.du_tfree;
318 fsb->f_bavail = fsd.du_tfree;
319 fsb->f_files = (fsd.du_isize - 2) * fsd.du_inopb;
320 fsb->f_ffree = fsd.du_tinode;
321 fsb->f_fsid.val[0] = fsd.du_site;
322 fsb->f_fsid.val[1] = fsd.du_pckno;
326 #endif /* _AIX && _I386 */