glibc/sysdeps/posix/pathconf.c

/* Copyright (C) 1991, 1995, 1996, 1998 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   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 <stddef.h>
#include <unistd.h>
#include <limits.h>
#include <fcntl.h>
#include <sys/statfs.h>

/* Get file-specific information about PATH.  */
long int
__pathconf (const char *path, int name)
{
  if (path[0] == '\0')
    {
      __set_errno (ENOENT);
      return -1;
    }

  switch (name)
    {
    default:
      __set_errno (EINVAL);
      return -1;

    case _PC_LINK_MAX:
#ifdef	LINK_MAX
      return LINK_MAX;
#else
      return -1;
#endif

    case _PC_MAX_CANON:
#ifdef	MAX_CANON
      return MAX_CANON;
#else
      return -1;
#endif

    case _PC_MAX_INPUT:
#ifdef	MAX_INPUT
      return MAX_INPUT;
#else
      return -1;
#endif

    case _PC_NAME_MAX:
#ifdef	NAME_MAX
      {
	struct statfs buf;
	int save_errno = errno;

	if (__statfs (path, &buf) < 0)
	  {
	    if (errno == ENOSYS)
	      {
		errno = save_errno;
		return NAME_MAX;
	      }
	    return -1;
	  }
	else
	  return buf.f_namelen;
      }
#else
      return -1;
#endif

    case _PC_PATH_MAX:
#ifdef	PATH_MAX
      return PATH_MAX;
#else
      return -1;
#endif

    case _PC_PIPE_BUF:
#ifdef	PIPE_BUF
      return PIPE_BUF;
#else
      return -1;
#endif

    case _PC_CHOWN_RESTRICTED:
#ifdef	_POSIX_CHOWN_RESTRICTED
      return _POSIX_CHOWN_RESTRICTED;
#else
      return -1;
#endif

    case _PC_NO_TRUNC:
#ifdef	_POSIX_NO_TRUNC
      return _POSIX_NO_TRUNC;
#else
      return -1;
#endif

    case _PC_VDISABLE:
#ifdef	_POSIX_VDISABLE
      return _POSIX_VDISABLE;
#else
      return -1;
#endif

    case _PC_SYNC_IO:
#ifdef	_POSIX_SYNC_IO
      return _POSIX_SYNC_IO;
#else
      return -1;
#endif

    case _PC_ASYNC_IO:
#ifdef	_POSIX_ASYNC_IO
      return _POSIX_ASYNC_IO;
#else
      return -1;
#endif

    case _PC_PRIO_IO:
#ifdef	_POSIX_PRIO_IO
      return _POSIX_PRIO_IO;
#else
      return -1;
#endif

    case _PC_SOCK_MAXBUF:
#ifdef	SOCK_MAXBUF
      return SOCK_MAXBUF;
#else
      return -1;
#endif

    case _PC_FILESIZEBITS:
#ifdef FILESIZEBITS
      return FILESIZEBITS;
#else
      /* We let platforms with larger file sizes overwrite this value.  */
      return 32;
#endif
    }
}

#undef __pathconf
weak_alias (__pathconf, pathconf)