// Copyright 2011 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "base/system/sys_info.h"

#include <stddef.h>
#include <stdint.h>
#include <sys/sysctl.h>

#include "base/notreached.h"
#include "base/numerics/safe_conversions.h"

namespace base {

ByteSize SysInfo::AmountOfTotalPhysicalMemoryImpl() {
  int pages, page_size;
  size_t size = sizeof(pages);
  sysctlbyname("vm.stats.vm.v_page_count", &pages, &size, NULL, 0);
  sysctlbyname("vm.stats.vm.v_page_size", &page_size, &size, NULL, 0);
  if (pages == -1 || page_size == -1) {
    NOTREACHED();
  }
  return ByteSize(checked_cast<unsigned>(page_size)) * pages;
}

// static
uint64_t SysInfo::MaxSharedMemorySize() {
  size_t limit;
  size_t size = sizeof(limit);
  if (sysctlbyname("kern.ipc.shmmax", &limit, &size, NULL, 0) < 0) {
    NOTREACHED();
  }
  return static_cast<uint64_t>(limit);
}

}  // namespace base