sysdeps/unix/sysv/linux/internal_statvfs.c

   1 /* Copyright (C) 1998-2024 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library 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 GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <https://www.gnu.org/licenses/>.  */
  17
  18 #include <sys/statfs.h>
  19 #include <sys/statvfs.h>
  20 #include <internal_statvfs.h>
  21 #include <string.h>
  22 #include <time.h>
  23 #include <kernel_stat.h>
  24
  25 /* Special internal-only bit value.  */
  26 # define ST_VALID 0x0020
  27
  28 #if !STATFS_IS_STATFS64
  29 void
  30 __internal_statvfs (struct statvfs *buf, const struct statfs *fsbuf)
  31 {
  32   /* Now fill in the fields we have information for.  */
  33   buf->f_bsize = fsbuf->f_bsize;
  34   /* Linux has the f_frsize size only in later version of the kernel.
  35      If the value is not filled in use f_bsize.  */
  36   buf->f_frsize = fsbuf->f_frsize ?: fsbuf->f_bsize;
  37   buf->f_blocks = fsbuf->f_blocks;
  38   buf->f_bfree = fsbuf->f_bfree;
  39   buf->f_bavail = fsbuf->f_bavail;
  40   buf->f_files = fsbuf->f_files;
  41   buf->f_ffree = fsbuf->f_ffree;
  42   if (sizeof (buf->f_fsid) == sizeof (fsbuf->f_fsid))
  43     /* The shifting uses 'unsigned long long int' even though the target
  44        field might only have 32 bits.  This is OK since the 'if' branch
  45        is not used in this case but the compiler would still generate
  46        warnings.  */
  47     buf->f_fsid = ((fsbuf->f_fsid.__val[0]
  48                     & ((1ULL << (8 * sizeof (fsbuf->f_fsid.__val[0]))) - 1))
  49                    | ((unsigned long long int) fsbuf->f_fsid.__val[1]
  50                       << (8 * (sizeof (buf->f_fsid)
  51                                - sizeof (fsbuf->f_fsid.__val[0])))));
  52   else
  53     /* We cannot help here.  The statvfs element is not large enough to
  54        contain both words of the statfs f_fsid field.  */
  55     buf->f_fsid = fsbuf->f_fsid.__val[0];
  56 #ifdef _STATVFSBUF_F_UNUSED
  57   buf->__f_unused = 0;
  58 #endif
  59   buf->f_namemax = fsbuf->f_namelen;
  60   buf->f_type = fsbuf->f_type;
  61   memset (buf->__f_spare, '\0', sizeof (buf->__f_spare));
  62
  63   /* What remains to do is to fill the fields f_favail and f_flag.  */
  64
  65   /* XXX I have no idea how to compute f_favail.  Any idea???  */
  66   buf->f_favail = buf->f_ffree;
  67
  68   buf->f_flag = fsbuf->f_flags ^ ST_VALID;
  69 }
  70 #endif
  71
  72 void
  73 __internal_statvfs64 (struct statvfs64 *buf, const struct statfs64 *fsbuf)
  74 {
  75   /* Now fill in the fields we have information for.  */
  76   buf->f_bsize = fsbuf->f_bsize;
  77   /* Linux has the f_frsize size only in later version of the kernel.
  78      If the value is not filled in use f_bsize.  */
  79   buf->f_frsize = fsbuf->f_frsize ?: fsbuf->f_bsize;
  80   buf->f_blocks = fsbuf->f_blocks;
  81   buf->f_bfree = fsbuf->f_bfree;
  82   buf->f_bavail = fsbuf->f_bavail;
  83   buf->f_files = fsbuf->f_files;
  84   buf->f_ffree = fsbuf->f_ffree;
  85   if (sizeof (buf->f_fsid) == sizeof (fsbuf->f_fsid))
  86     /* The shifting uses 'unsigned long long int' even though the target
  87        field might only have 32 bits.  This is OK since the 'if' branch
  88        is not used in this case but the compiler would still generate
  89        warnings.  */
  90     buf->f_fsid = ((fsbuf->f_fsid.__val[0]
  91                     & ((1ULL << (8 * sizeof (fsbuf->f_fsid.__val[0]))) - 1))
  92                    | ((unsigned long long int) fsbuf->f_fsid.__val[1]
  93                       << (8 * (sizeof (buf->f_fsid)
  94                                - sizeof (fsbuf->f_fsid.__val[0])))));
  95   else
  96     /* We cannot help here.  The statvfs element is not large enough to
  97        contain both words of the statfs f_fsid field.  */
  98     buf->f_fsid = fsbuf->f_fsid.__val[0];
  99 #ifdef _STATVFSBUF_F_UNUSED
 100   buf->__f_unused = 0;
 101 #endif
 102   buf->f_namemax = fsbuf->f_namelen;
 103   buf->f_type = fsbuf->f_type;
 104   memset (buf->__f_spare, '\0', sizeof (buf->__f_spare));
 105
 106   /* What remains to do is to fill the fields f_favail and f_flag.  */
 107
 108   /* XXX I have no idea how to compute f_favail.  Any idea???  */
 109   buf->f_favail = buf->f_ffree;
 110
 111   buf->f_flag = fsbuf->f_flags ^ ST_VALID;
 112 }