Remove Hung plugin detector

chrome/browser/hang_monitor/hung_window_detector.cc

-// 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 "chrome/browser/hang_monitor/hung_window_detector.h"
-
-#include <windows.h>
-#include <atlbase.h>
-
-#include "base/logging.h"
-#include "base/win/win_util.h"
-#include "chrome/browser/hang_monitor/hang_crash_dump_win.h"
-#include "content/public/common/result_codes.h"
-
-const wchar_t HungWindowDetector::kHungChildWindowTimeout[] =
-    L"Chrome_HungChildWindowTimeout";
-
-HungWindowDetector::HungWindowDetector(HungWindowNotification* notification)
-    : notification_(notification),
-      top_level_window_(NULL),
-      message_response_timeout_(0),
-      enumerating_(false) {
-  DCHECK(NULL != notification_);
-}
-// NOTE: It is the caller's responsibility to make sure that
-// callbacks on this object have been stopped before
-// destroying this object
-HungWindowDetector::~HungWindowDetector() {
-}
-
-bool HungWindowDetector::Initialize(HWND top_level_window,
-                                    int message_response_timeout) {
-  if (NULL ==  notification_) {
-    return false;
-  }
-  if (NULL == top_level_window) {
-    return false;
-  }
-  // It is OK to call Initialize on this object repeatedly
-  // with different top lebel HWNDs and timeout values each time.
-  // And we do not need a lock for this because we are just
-  // swapping DWORDs.
-  top_level_window_ = top_level_window;
-  message_response_timeout_ = message_response_timeout;
-  return true;
-}
-
-void HungWindowDetector::OnTick() {
-  do {
-    base::AutoLock lock(hang_detection_lock_);
-    // If we already are checking for hung windows on another thread,
-    // don't do this again.
-    if (enumerating_) {
-      return;
-    }
-    enumerating_ = true;
-  } while (false);  // To scope the AutoLock
-
-  EnumChildWindows(top_level_window_, ChildWndEnumProc,
-                   reinterpret_cast<LPARAM>(this));
-
-  // The window shouldn't be disabled unless we're showing a modal dialog.
-  // If we're not, then reenable the window.
-  if (!::IsWindowEnabled(top_level_window_) &&
-      !::GetWindow(top_level_window_, GW_ENABLEDPOPUP)) {
-    ::EnableWindow(top_level_window_, TRUE);
-  }
-
-  enumerating_ = false;
-}
-
-bool HungWindowDetector::CheckChildWindow(HWND child_window) {
-  // It can happen that the window is DOA. It specifically happens
-  // when we have just killed a plugin process and the enum is still
-  // enumerating windows from that process.
-  if (!IsWindow(child_window))  {
-    return true;
-  }
-
-  DWORD top_level_window_thread_id =
-      GetWindowThreadProcessId(top_level_window_, NULL);
-
-  DWORD child_window_process_id = 0;
-  DWORD child_window_thread_id =
-      GetWindowThreadProcessId(child_window, &child_window_process_id);
-  bool continue_hang_detection = true;
-
-  if (top_level_window_thread_id != child_window_thread_id) {
-    // The message timeout for a child window starts of with a default
-    // value specified by the message_response_timeout_ member. It is
-    // tracked by a property on the child window.
-    int child_window_message_timeout = base::win::HandleToUint32(
-        GetProp(child_window, kHungChildWindowTimeout));
-    if (!child_window_message_timeout) {
-      child_window_message_timeout = message_response_timeout_;
-    }
-
-    DWORD_PTR result = 0;
-    if (0 == SendMessageTimeout(child_window,
-                                WM_NULL,
-                                0,
-                                0,
-                                SMTO_BLOCK,
-                                child_window_message_timeout,
-                                &result)) {
-      HungWindowNotification::ActionOnHungWindow action =
-          HungWindowNotification::HUNG_WINDOW_IGNORE;
-#pragma warning(disable:4312)
-      SetProp(child_window, kHungChildWindowTimeout,
-              reinterpret_cast<HANDLE>(child_window_message_timeout));
-#pragma warning(default:4312)
-      continue_hang_detection =
-        notification_->OnHungWindowDetected(child_window, top_level_window_,
-                                            &action);
-      // Make sure this window still a child of our top-level parent
-      if (!IsChild(top_level_window_, child_window)) {
-        return continue_hang_detection;
-      }
-
-      if (action == HungWindowNotification::HUNG_WINDOW_TERMINATE_PROCESS) {
-        RemoveProp(child_window, kHungChildWindowTimeout);
-        CHandle child_process(OpenProcess(PROCESS_ALL_ACCESS,
-                                          FALSE,
-                                          child_window_process_id));
-
-        if (NULL == child_process.m_h) {
-          return continue_hang_detection;
-        }
-        // Before swinging the axe, do some sanity checks to make
-        // sure this window still belongs to the same process
-        DWORD process_id_check = 0;
-        GetWindowThreadProcessId(child_window, &process_id_check);
-        if (process_id_check !=  child_window_process_id) {
-          return continue_hang_detection;
-        }
-
-        // Before terminating the process we try collecting a dump. Which
-        // a transient thread in the child process will do for us.
-        CrashDumpAndTerminateHungChildProcess(child_process);
-        child_process.Close();
-      }
-    } else {
-      RemoveProp(child_window, kHungChildWindowTimeout);
-    }
-  }
-
-  return continue_hang_detection;
-}
-
-BOOL CALLBACK HungWindowDetector::ChildWndEnumProc(HWND child_window,
-                                                   LPARAM param) {
-  HungWindowDetector* detector_instance =
-      reinterpret_cast<HungWindowDetector*>(param);
-  if (NULL == detector_instance) {
-    NOTREACHED();
-    return FALSE;
-  }
-
-  return detector_instance->CheckChildWindow(child_window);
-}