mvalloc.c

早期freebsd实现

/* Allocate memory on a page boundary.
   Copyright (C) 1991 Free Software Foundation, Inc.

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., 675 Mass Ave,
Cambridge, MA 02139, USA.  */

#include "mmalloc.h"

/* Cache the pagesize for the current host machine.  Note that if the host
   does not readily provide a getpagesize() function, we need to emulate it
   elsewhere, not clutter up this file with lots of kluges to try to figure
   it out. */

static size_t pagesize;
extern int getpagesize PARAMS ((void));

PTR
mvalloc (md, size)
  PTR md;
  size_t size;
{
  if (pagesize == 0)
    {
      pagesize = getpagesize ();
    }

  return (mmemalign (md, pagesize, size));
}