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 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 VMS
  23 #  define getpagesize() 512
  24 # endif
  25
  26 # ifdef HAVE_UNISTD_H
  27 #  include <unistd.h>
  28 # endif
  29
  30 # ifdef _SC_PAGESIZE
  31 #  define getpagesize() sysconf(_SC_PAGESIZE)
  32 # else /* no _SC_PAGESIZE */
  33 #  ifdef HAVE_SYS_PARAM_H
  34 #   include <sys/param.h>
  35 #   ifdef EXEC_PAGESIZE
  36 #    define getpagesize() EXEC_PAGESIZE
  37 #   else /* no EXEC_PAGESIZE */
  38 #    ifdef NBPG
  39 #     define getpagesize() NBPG * CLSIZE
  40 #     ifndef CLSIZE
  41 #      define CLSIZE 1
  42 #     endif /* no CLSIZE */
  43 #    else /* no NBPG */
  44 #      ifdef PAGESIZE
  45 #       define getpagesize() PAGESIZE
  46 #      endif /* PAGESIZE */
  47 #    endif /* no NBPG */
  48 #   endif /* no EXEC_PAGESIZE */
  49 #  else /* no HAVE_SYS_PARAM_H */
  50 #   define getpagesize() 8192   /* punt totally */
  51 #  endif /* no HAVE_SYS_PARAM_H */
  52 # endif /* no _SC_PAGESIZE */
  53
  54 #endif /* no HAVE_GETPAGESIZE */
  55
  56 /* arch-tag: ff6206e3-97e2-4763-923a-e84bf28eabbc
  57    (do not change this comment) */