lib/malloc/getpagesize.h

   1 /* Emulation of getpagesize() for systems that need it.
   2    Copyright (C) 1991 Free Software Foundation, Inc.
   3
   4 This program is free software; you can redistribute it and/or modify
   5 it under the terms of the GNU General Public License as published by
   6 the Free Software Foundation; either version 2 of the License, or
   7 (at your option) any later version.
   8
   9 This program 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
  12 GNU General Public License for more details.
  13
  14 You should have received a copy of the GNU General Public License
  15 along with this program; if not, write to the Free Software
  16 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  17
  18 #if defined (HAVE_UNISTD_H)
  19 #  ifdef _MINIX
  20 #    include <sys/types.h>
  21 #  endif
  22 #  include <unistd.h>
  23 #  if defined (_SC_PAGESIZE)
  24 #    define getpagesize() sysconf(_SC_PAGESIZE)
  25 #  else
  26 #    if defined (_SC_PAGE_SIZE)
  27 #      define getpagesize() sysconf(_SC_PAGE_SIZE)
  28 #    endif /* _SC_PAGE_SIZE */
  29 #  endif /* _SC_PAGESIZE */
  30 #endif
  31
  32 #if !defined (getpagesize)
  33 #  ifndef _MINIX
  34 #    include <sys/param.h>
  35 #  endif
  36 #  if defined (PAGESIZE)
  37 #     define getpagesize() PAGESIZE
  38 #  else /* !PAGESIZE */
  39 #    if defined (EXEC_PAGESIZE)
  40 #      define getpagesize() EXEC_PAGESIZE
  41 #    else /* !EXEC_PAGESIZE */
  42 #      if defined (NBPG)
  43 #        if !defined (CLSIZE)
  44 #          define CLSIZE 1
  45 #        endif /* !CLSIZE */
  46 #        define getpagesize() (NBPG * CLSIZE)
  47 #      else /* !NBPG */
  48 #        if defined (NBPC)
  49 #          define getpagesize() NBPC
  50 #        endif /* NBPC */
  51 #      endif /* !NBPG */
  52 #    endif /* !EXEC_PAGESIZE */
  53 #  endif /* !PAGESIZE */
  54 #endif /* !getpagesize */
  55
  56 #if !defined (getpagesize)
  57 #  define getpagesize() 4096  /* Just punt and use reasonable value */
  58 #endif