sysdeps/posix/fpathconf.c

   1 /* Copyright (C) 1991,1995,1996,1998,2000,2001 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 Library General Public License as
   6    published by the Free Software Foundation; either version 2 of the
   7    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    Library General Public License for more details.
  13
  14    You should have received a copy of the GNU Library General Public
  15    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 02111-1307, USA.  */
  18
  19 #include <errno.h>
  20 #include <stddef.h>
  21 #include <unistd.h>
  22 #include <limits.h>
  23 #include <sys/statfs.h>
  24 #include <sys/statvfs.h>
  25
  26
  27 /* Get file-specific information about descriptor FD.  */
  28 long int
  29 __fpathconf (fd, name)
  30      int fd;
  31      int name;
  32 {
  33   if (fd < 0)
  34     {
  35       __set_errno (EBADF);
  36       return -1;
  37     }
  38
  39   switch (name)
  40     {
  41     default:
  42       __set_errno (EINVAL);
  43       return -1;
  44
  45     case _PC_LINK_MAX:
  46 #ifdef  LINK_MAX
  47       return LINK_MAX;
  48 #else
  49       return -1;
  50 #endif
  51
  52     case _PC_MAX_CANON:
  53 #ifdef  MAX_CANON
  54       return MAX_CANON;
  55 #else
  56       return -1;
  57 #endif
  58
  59     case _PC_MAX_INPUT:
  60 #ifdef  MAX_INPUT
  61       return MAX_INPUT;
  62 #else
  63       return -1;
  64 #endif
  65
  66     case _PC_NAME_MAX:
  67 #ifdef  NAME_MAX
  68       {
  69         struct statfs buf;
  70         int save_errno = errno;
  71
  72         if (__fstatfs (fd, &buf) < 0)
  73           {
  74             if (errno == ENOSYS)
  75               {
  76                 __set_errno (save_errno);
  77                 return NAME_MAX;
  78               }
  79             else if (errno == ENODEV)
  80               __set_errno (EINVAL);
  81
  82             return -1;
  83           }
  84         else
  85           {
  86 #ifdef _STATFS_F_NAMELEN
  87             return buf.f_namelen;
  88 #else
  89 # ifdef _STATFS_F_NAME_MAX
  90             return buf.f_name_max;
  91 # else
  92             return NAME_MAX;
  93 # endif
  94 #endif
  95           }
  96       }
  97 #else
  98       return -1;
  99 #endif
 100
 101     case _PC_PATH_MAX:
 102 #ifdef  PATH_MAX
 103       return PATH_MAX;
 104 #else
 105       return -1;
 106 #endif
 107
 108     case _PC_PIPE_BUF:
 109 #ifdef  PIPE_BUF
 110       return PIPE_BUF;
 111 #else
 112       return -1;
 113 #endif
 114
 115     case _PC_CHOWN_RESTRICTED:
 116 #ifdef  _POSIX_CHOWN_RESTRICTED
 117       return _POSIX_CHOWN_RESTRICTED;
 118 #else
 119       return -1;
 120 #endif
 121
 122     case _PC_NO_TRUNC:
 123 #ifdef  _POSIX_NO_TRUNC
 124       return _POSIX_NO_TRUNC;
 125 #else
 126       return -1;
 127 #endif
 128
 129     case _PC_VDISABLE:
 130 #ifdef  _POSIX_VDISABLE
 131       return _POSIX_VDISABLE;
 132 #else
 133       return -1;
 134 #endif
 135
 136     case _PC_SYNC_IO:
 137 #ifdef  _POSIX_SYNC_IO
 138       return _POSIX_SYNC_IO;
 139 #else
 140       return -1;
 141 #endif
 142
 143     case _PC_ASYNC_IO:
 144 #ifdef  _POSIX_ASYNC_IO
 145       return _POSIX_ASYNC_IO;
 146 #else
 147       return -1;
 148 #endif
 149
 150     case _PC_PRIO_IO:
 151 #ifdef  _POSIX_PRIO_IO
 152       return _POSIX_PRIO_IO;
 153 #else
 154       return -1;
 155 #endif
 156
 157     case _PC_SOCK_MAXBUF:
 158 #ifdef  SOCK_MAXBUF
 159       return SOCK_MAXBUF;
 160 #else
 161       return -1;
 162 #endif
 163
 164     case _PC_FILESIZEBITS:
 165 #ifdef FILESIZEBITS
 166       return FILESIZEBITS;
 167 #else
 168       /* We let platforms with larger file sizes overwrite this value.  */
 169       return 32;
 170 #endif
 171
 172     case _PC_REC_INCR_XFER_SIZE:
 173       /* XXX It is not entirely clear what the limit is supposed to do.
 174          What is incremented?  */
 175       return -1;
 176
 177     case _PC_REC_MAX_XFER_SIZE:
 178       /* XXX It is not entirely clear what the limit is supposed to do.
 179          In general there is no top limit of the number of bytes which
 180          case be transported at once.  */
 181       return -1;
 182
 183     case _PC_REC_MIN_XFER_SIZE:
 184       {
 185         /* XXX It is not entirely clear what the limit is supposed to do.
 186            I assume this is the block size of the filesystem.  */
 187         struct statvfs64 sv;
 188
 189         if (__fstatvfs64 (fd, &sv) < 0)
 190           return -1;
 191         return sv.f_bsize;
 192       }
 193
 194     case _PC_REC_XFER_ALIGN:
 195       {
 196         /* XXX It is not entirely clear what the limit is supposed to do.
 197            I assume that the number should reflect the minimal block
 198            alignment.  */
 199         struct statvfs64 sv;
 200
 201         if (__fstatvfs64 (fd, &sv) < 0)
 202           return -1;
 203         return sv.f_frsize;
 204       }
 205     }
 206 }
 207
 208 #undef __fpathconf
 209 weak_alias (__fpathconf, fpathconf)