about summary refs log tree commit diff
path: root/sysdeps/unix/sysv/linux/fstatvfs.c
blob: 11f6f8eb44fa7943abd8fe5dfdbedd1addd47960 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
/* Copyright (C) 1998 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public License as
   published by the Free Software Foundation; either version 2 of the
   License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#include <errno.h>
#include <mntent.h>
#include <paths.h>
#include <string.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/statfs.h>
#include <sys/statvfs.h>

#include "linux_fsinfo.h"


int
fstatvfs (int fd, struct statvfs *buf)
{
  struct statfs fsbuf;
  struct stat st;

  /* Get as much information as possible from the system.  */
  if (__fstatfs (fd, &fsbuf) < 0)
    return -1;

  /* Now fill in the fields we have information for.  */
  buf->f_bsize = fsbuf.f_bsize;
  buf->f_blocks = fsbuf.f_blocks;
  buf->f_bfree = fsbuf.f_bfree;
  buf->f_bavail = fsbuf.f_bavail;
  buf->f_files = fsbuf.f_files;
  buf->f_ffree = fsbuf.f_ffree;
  buf->f_fsid = fsbuf.f_fsid;
  buf->f_namemax = fsbuf.f_namelen;
  memset (buf->f_spare, '\0', 6 * sizeof (int));

  /* What remains to do is to fill the fields f_frsize, f_favail,
     and f_flag.  */
  switch (fsbuf.f_type)
    {
    case EXT2_SUPER_MAGIC:
      /* This is not really correct since the fragment size can vary.  */
      buf->f_frsize = 1024;
      break;

    case ADFS_SUPER_MAGIC:
    case AFFS_SUPER_MAGIC:
    case CODA_SUPER_MAGIC:
    case HPFS_SUPER_MAGIC:
    case ISOFS_SUPER_MAGIC:
    case MINIX_SUPER_MAGIC:
    case MINIX_SUPER_MAGIC2:
    case MINIX2_SUPER_MAGIC:
    case MINIX2_SUPER_MAGIC2:
    case MSDOS_SUPER_MAGIC:
    case NCP_SUPER_MAGIC:
    case NFS_SUPER_MAGIC:
    case PROC_SUPER_MAGIC:
    case SMB_SUPER_MAGIC:
    case XENIX_SUPER_MAGIC:
    case SYSV4_SUPER_MAGIC:
    case SYSV2_SUPER_MAGIC:
    case COH_SUPER_MAGIC:
    case UFS_MAGIC:
    case UFS_CIGAM:
    default:
      /* I hope it's safe to assume no fragmentation.  */
      buf->f_frsize = buf->f_bsize;
      break;
    }

  /* XXX I have no idea how to compute f_favail.  Any idea???  */
  buf->f_favail = buf->f_ffree;

  /* Determining the flags is tricky.  We have to read /proc/mounts or
     the /etc/mtab file and search for the entry which matches the given
     file.  The way we can test for matching filesystem is using the
     device number.  */
  buf->f_flag = 0;
  if (fstat (fd, &st) >= 0)
    {
      int save_errno = errno;
      struct mntent mntbuf;
      FILE *mtab;

      mtab = __setmntent ("/proc/mounts", "r");
      if (mtab == NULL)
	mtab = __setmntent (_PATH_MOUNTED, "r");

      if (mtab != NULL)
	{
	  char tmpbuf[1024];

	  while (__getmntent_r (mtab, &mntbuf, tmpbuf, sizeof (tmpbuf)))
	    {
	      struct stat fsst;

	      /* Find out about the device the current entry is for.  */
	      if (stat (mntbuf.mnt_dir, &fsst) >= 0
		  && st.st_dev == fsst.st_dev)
		{
		  /* Bingo, we found the entry for the device FD is on.
		     Now interpret the option string.  */
		  char *cp = mntbuf.mnt_opts;
		  char *opt;

		  while ((opt = strsep (&cp, ",")) != NULL)
		    if (strcmp (opt, "ro") == 0)
		      buf->f_flag |= ST_RDONLY;
		    else if (strcmp (opt, "nosuid") == 0)
		      buf->f_flag |= ST_NOSUID;
		    else if (strcmp (opt, "noexec") == 0)
		      buf->f_flag |= ST_NOEXEC;
		    else if (strcmp (opt, "nodev") == 0)
		      buf->f_flag |= ST_NODEV;
		    else if (strcmp (opt, "sync") == 0)
		      buf->f_flag |= ST_SYNCHRONOUS;
		    else if (strcmp (opt, "mand") == 0)
		      buf->f_flag |= ST_MANDLOCK;
		    else if (strcmp (opt, "noatime") == 0)
		      buf->f_flag |= ST_NOATIME;
		    else if (strcmp (opt, "nodiratime") == 0)
		      buf->f_flag |= ST_NODIRATIME;

		  /* We can stop looking for more entries.  */
		  break;
		}
	    }

	  /* Close the file.  */
	  __endmntent (mtab);
	}

      __set_errno (save_errno);
    }

  /* We signal success if the statfs call succeeded.  */
  return 0;
}