1 /* fsusage.c -- return space usage of mounted file systems
3 Copyright (C) 1991-1992, 1996, 1998-1999, 2002-2006, 2009-2012 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 /* The results of open() in this file are not used with fchdir,
59 therefore save some unnecessary work in fchdir.c. */
63 /* Many space usage primitives use all 1 bits to denote a value that is
64 not applicable or unknown. Propagate this information by returning
65 a uintmax_t value that is all 1 bits if X is all 1 bits, even if X
66 is unsigned and narrower than uintmax_t. */
67 #define PROPAGATE_ALL_ONES(x) \
68 ((sizeof (x) < sizeof (uintmax_t) \
69 && (~ (x) == (sizeof (x) < sizeof (int) \
70 ? - (1 << (sizeof (x) * CHAR_BIT)) \
72 ? UINTMAX_MAX : (uintmax_t) (x))
74 /* Extract the top bit of X as an uintmax_t value. */
75 #define EXTRACT_TOP_BIT(x) ((x) \
76 & ((uintmax_t) 1 << (sizeof (x) * CHAR_BIT - 1)))
78 /* If a value is negative, many space usage primitives store it into an
79 integer variable by assignment, even if the variable's type is unsigned.
80 So, if a space usage variable X's top bit is set, convert X to the
81 uintmax_t value V such that (- (uintmax_t) V) is the negative of
82 the original value. If X's top bit is clear, just yield X.
83 Use PROPAGATE_TOP_BIT if the original value might be negative;
84 otherwise, use PROPAGATE_ALL_ONES. */
85 #define PROPAGATE_TOP_BIT(x) ((x) | ~ (EXTRACT_TOP_BIT (x) - 1))
88 /* Return true if statvfs works. This is false for statvfs on systems
89 with GNU libc on Linux kernels before 2.6.36, which stats all
90 preceding entries in /proc/mounts; that makes df hang if even one
91 of the corresponding file systems is hard-mounted but not available. */
92 # if ! (__linux__ && (__GLIBC__ || __UCLIBC__))
93 static int statvfs_works (void) { return 1; }
95 # include <string.h> /* for strverscmp */
96 # include <sys/utsname.h>
97 # include <sys/statfs.h>
98 # define STAT_STATFS2_BSIZE 1
103 static int statvfs_works_cache = -1;
105 if (statvfs_works_cache < 0)
106 statvfs_works_cache = (uname (&name) == 0
107 && 0 <= strverscmp (name.release, "2.6.36"));
108 return statvfs_works_cache;
114 /* Fill in the fields of FSP with information about space usage for
115 the file system on which FILE resides.
116 DISK is the device on which FILE is mounted, for space-getting
117 methods that need to know it.
118 Return 0 if successful, -1 if not. When returning -1, ensure that
119 ERRNO is either a system error value, or zero if DISK is NULL
120 on a system that requires a non-NULL value. */
122 get_fs_usage (char const *file, char const *disk, struct fs_usage *fsp)
124 #ifdef STAT_STATVFS /* POSIX, except pre-2.6.36 glibc/Linux */
126 if (statvfs_works ())
130 if (statvfs (file, &vfsd) < 0)
133 /* f_frsize isn't guaranteed to be supported. */
134 fsp->fsu_blocksize = (vfsd.f_frsize
135 ? PROPAGATE_ALL_ONES (vfsd.f_frsize)
136 : PROPAGATE_ALL_ONES (vfsd.f_bsize));
138 fsp->fsu_blocks = PROPAGATE_ALL_ONES (vfsd.f_blocks);
139 fsp->fsu_bfree = PROPAGATE_ALL_ONES (vfsd.f_bfree);
140 fsp->fsu_bavail = PROPAGATE_TOP_BIT (vfsd.f_bavail);
141 fsp->fsu_bavail_top_bit_set = EXTRACT_TOP_BIT (vfsd.f_bavail) != 0;
142 fsp->fsu_files = PROPAGATE_ALL_ONES (vfsd.f_files);
143 fsp->fsu_ffree = PROPAGATE_ALL_ONES (vfsd.f_ffree);
149 #if defined STAT_STATVFS64 /* AIX */
151 struct statvfs64 fsd;
153 if (statvfs64 (file, &fsd) < 0)
156 /* f_frsize isn't guaranteed to be supported. */
157 fsp->fsu_blocksize = (fsd.f_frsize
158 ? PROPAGATE_ALL_ONES (fsd.f_frsize)
159 : PROPAGATE_ALL_ONES (fsd.f_bsize));
161 #elif defined STAT_STATFS2_FS_DATA /* Ultrix */
165 if (statfs (file, &fsd) != 1)
168 fsp->fsu_blocksize = 1024;
169 fsp->fsu_blocks = PROPAGATE_ALL_ONES (fsd.fd_req.btot);
170 fsp->fsu_bfree = PROPAGATE_ALL_ONES (fsd.fd_req.bfree);
171 fsp->fsu_bavail = PROPAGATE_TOP_BIT (fsd.fd_req.bfreen);
172 fsp->fsu_bavail_top_bit_set = EXTRACT_TOP_BIT (fsd.fd_req.bfreen) != 0;
173 fsp->fsu_files = PROPAGATE_ALL_ONES (fsd.fd_req.gtot);
174 fsp->fsu_ffree = PROPAGATE_ALL_ONES (fsd.fd_req.gfree);
176 #elif defined STAT_READ_FILSYS /* SVR2 */
178 # define SUPERBOFF (SUPERB * 512)
190 fd = open (disk, O_RDONLY);
193 lseek (fd, (off_t) SUPERBOFF, 0);
194 if (full_read (fd, (char *) &fsd, sizeof fsd) != sizeof fsd)
201 fsp->fsu_blocksize = (fsd.s_type == Fs2b ? 1024 : 512);
202 fsp->fsu_blocks = PROPAGATE_ALL_ONES (fsd.s_fsize);
203 fsp->fsu_bfree = PROPAGATE_ALL_ONES (fsd.s_tfree);
204 fsp->fsu_bavail = PROPAGATE_TOP_BIT (fsd.s_tfree);
205 fsp->fsu_bavail_top_bit_set = EXTRACT_TOP_BIT (fsd.s_tfree) != 0;
206 fsp->fsu_files = (fsd.s_isize == -1
208 : (fsd.s_isize - 2) * INOPB * (fsd.s_type == Fs2b ? 2 : 1));
209 fsp->fsu_ffree = PROPAGATE_ALL_ONES (fsd.s_tinode);
211 #elif defined STAT_STATFS3_OSF1 /* OSF/1 */
215 if (statfs (file, &fsd, sizeof (struct statfs)) != 0)
218 fsp->fsu_blocksize = PROPAGATE_ALL_ONES (fsd.f_fsize);
220 #elif defined STAT_STATFS2_FRSIZE /* 2.6 < glibc/Linux < 2.6.36 */
224 if (statfs (file, &fsd) < 0)
227 fsp->fsu_blocksize = PROPAGATE_ALL_ONES (fsd.f_frsize);
229 #elif defined STAT_STATFS2_BSIZE /* glibc/Linux < 2.6, 4.3BSD, SunOS 4, \
230 Mac OS X < 10.4, FreeBSD < 5.0, \
231 NetBSD < 3.0, OpenBSD < 4.4 */
235 if (statfs (file, &fsd) < 0)
238 fsp->fsu_blocksize = PROPAGATE_ALL_ONES (fsd.f_bsize);
240 # ifdef STATFS_TRUNCATES_BLOCK_COUNTS
242 /* In SunOS 4.1.2, 4.1.3, and 4.1.3_U1, the block counts in the
243 struct statfs are truncated to 2GB. These conditions detect that
244 truncation, presumably without botching the 4.1.1 case, in which
245 the values are not truncated. The correct counts are stored in
246 undocumented spare fields. */
247 if (fsd.f_blocks == 0x7fffffff / fsd.f_bsize && fsd.f_spare[0] > 0)
249 fsd.f_blocks = fsd.f_spare[0];
250 fsd.f_bfree = fsd.f_spare[1];
251 fsd.f_bavail = fsd.f_spare[2];
253 # endif /* STATFS_TRUNCATES_BLOCK_COUNTS */
255 #elif defined STAT_STATFS2_FSIZE /* 4.4BSD and older NetBSD */
259 if (statfs (file, &fsd) < 0)
262 fsp->fsu_blocksize = PROPAGATE_ALL_ONES (fsd.f_fsize);
264 #elif defined STAT_STATFS4 /* SVR3, Dynix, old Irix, old AIX, \
267 # if !_AIX && !defined _SEQUENT_ && !defined DOLPHIN
268 # define f_bavail f_bfree
273 if (statfs (file, &fsd, sizeof fsd, 0) < 0)
276 /* Empirically, the block counts on most SVR3 and SVR3-derived
277 systems seem to always be in terms of 512-byte blocks,
278 no matter what value f_bsize has. */
279 # if _AIX || defined _CRAY
280 fsp->fsu_blocksize = PROPAGATE_ALL_ONES (fsd.f_bsize);
282 fsp->fsu_blocksize = 512;
287 #if (defined STAT_STATVFS64 \
288 || (!defined STAT_STATFS2_FS_DATA && !defined STAT_READ_FILSYS))
290 fsp->fsu_blocks = PROPAGATE_ALL_ONES (fsd.f_blocks);
291 fsp->fsu_bfree = PROPAGATE_ALL_ONES (fsd.f_bfree);
292 fsp->fsu_bavail = PROPAGATE_TOP_BIT (fsd.f_bavail);
293 fsp->fsu_bavail_top_bit_set = EXTRACT_TOP_BIT (fsd.f_bavail) != 0;
294 fsp->fsu_files = PROPAGATE_ALL_ONES (fsd.f_files);
295 fsp->fsu_ffree = PROPAGATE_ALL_ONES (fsd.f_ffree);
299 (void) disk; /* avoid argument-unused warning */
303 #if defined _AIX && defined _I386
304 /* AIX PS/2 does not supply statfs. */
307 statfs (char *file, struct statfs *fsb)
312 if (stat (file, &stats) != 0)
314 if (dustat (stats.st_dev, 0, &fsd, sizeof (fsd)))
317 fsb->f_bsize = fsd.du_bsize;
318 fsb->f_blocks = fsd.du_fsize - fsd.du_isize;
319 fsb->f_bfree = fsd.du_tfree;
320 fsb->f_bavail = fsd.du_tfree;
321 fsb->f_files = (fsd.du_isize - 2) * fsd.du_inopb;
322 fsb->f_ffree = fsd.du_tinode;
323 fsb->f_fsid.val[0] = fsd.du_site;
324 fsb->f_fsid.val[1] = fsd.du_pckno;
328 #endif /* _AIX && _I386 */