/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "prbit.h"
#include "prsystem.h"

#ifdef XP_UNIX
#  include <unistd.h>
#endif
#ifdef _WIN32
#  include <windows.h>
#endif

PRInt32 _pr_pageShift;
PRInt32 _pr_pageSize;

/*
** Get system page size
*/
static void GetPageSize(void) {
  PRInt32 pageSize;

  /* Get page size */
#ifdef XP_UNIX
#  if defined AIX || defined LINUX || defined __GNU__ || defined __GLIBC__ || \
      defined FREEBSD || defined NETBSD || defined OPENBSD || defined DARWIN
  _pr_pageSize = getpagesize();
#  else
  _pr_pageSize = sysconf(_SC_PAGESIZE);
#  endif
#endif /* XP_UNIX */

#ifdef XP_PC
#  ifdef _WIN32
  SYSTEM_INFO info;
  GetSystemInfo(&info);
  _pr_pageSize = info.dwPageSize;
#  else
  _pr_pageSize = 4096;
#  endif
#endif /* XP_PC */

  pageSize = _pr_pageSize;
  PR_CEILING_LOG2(_pr_pageShift, pageSize);
}

PR_IMPLEMENT(PRInt32) PR_GetPageShift(void) {
  if (!_pr_pageSize) {
    GetPageSize();
  }
  return _pr_pageShift;
}

PR_IMPLEMENT(PRInt32) PR_GetPageSize(void) {
  if (!_pr_pageSize) {
    GetPageSize();
  }
  return _pr_pageSize;
}