src/getpagesize.h

   1 /* Emulate getpagesize on systems that lack it.
   2    Copyright (C) 1986, 1992, 1995, 2001, 2002, 2003, 2004,
   3                  2005, 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
   4
   5 This file is part of GNU Emacs.
   6
   7 GNU Emacs is free software: you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation, either version 3 of the License, or
  10 (at your option) any later version.
  11
  12 GNU Emacs is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef HAVE_GETPAGESIZE
  21
  22 # ifdef HAVE_UNISTD_H
  23 #  include <unistd.h>
  24 # endif
  25
  26 # ifdef _SC_PAGESIZE
  27 #  define getpagesize() sysconf(_SC_PAGESIZE)
  28 # else /* no _SC_PAGESIZE */
  29 #  ifdef HAVE_SYS_PARAM_H
  30 #   include <sys/param.h>
  31 #   ifdef EXEC_PAGESIZE
  32 #    define getpagesize() EXEC_PAGESIZE
  33 #   else /* no EXEC_PAGESIZE */
  34 #    ifdef NBPG
  35 #     define getpagesize() NBPG * CLSIZE
  36 #     ifndef CLSIZE
  37 #      define CLSIZE 1
  38 #     endif /* no CLSIZE */
  39 #    else /* no NBPG */
  40 #      ifdef PAGESIZE
  41 #       define getpagesize() PAGESIZE
  42 #      endif /* PAGESIZE */
  43 #    endif /* no NBPG */
  44 #   endif /* no EXEC_PAGESIZE */
  45 #  else /* no HAVE_SYS_PARAM_H */
  46 #   define getpagesize() 8192   /* punt totally */
  47 #  endif /* no HAVE_SYS_PARAM_H */
  48 # endif /* no _SC_PAGESIZE */
  49
  50 #endif /* no HAVE_GETPAGESIZE */
  51
  52 /* arch-tag: ff6206e3-97e2-4763-923a-e84bf28eabbc
  53    (do not change this comment) */