// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "base/process_info.h"

#include <sys/sysctl.h>
#include <sys/time.h>
#include <unistd.h>

#include "base/basictypes.h"
#include "base/memory/scoped_ptr.h"
#include "base/time.h"

namespace {

using base::Time;

// Returns the process creation time, or NULL if an error occurred.
Time* ProcessCreationTimeInternal() {
  int mib[] = { CTL_KERN, KERN_PROC, KERN_PROC_PID, getpid() };
  size_t len = 0;
  if (sysctl(mib, arraysize(mib), NULL, &len, NULL, 0) < 0)
    return NULL;

  scoped_ptr_malloc<struct kinfo_proc>
      proc(static_cast<struct kinfo_proc*>(malloc(len)));
  if (sysctl(mib, arraysize(mib), proc.get(), &len, NULL, 0) < 0)
    return NULL;
  return new Time(Time::FromTimeVal(proc->kp_proc.p_un.__p_starttime));
}

}  // namespace

namespace base {

//static
const Time* CurrentProcessInfo::CreationTime() {
  static Time* process_creation_time = ProcessCreationTimeInternal();
  return process_creation_time;
}

}  // namespace base