content/public/browser/render_process_host_observer.h

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CONTENT_PUBLIC_BROWSER_RENDER_PROCESS_HOST_OBSERVER_H_
   6 #define CONTENT_PUBLIC_BROWSER_RENDER_PROCESS_HOST_OBSERVER_H_
   7
   8 #include "base/process/kill.h"
   9 #include "base/process/process_handle.h"
  10 #include "content/common/content_export.h"
  11
  12 namespace content {
  13
  14 class RenderProcessHost;
  15
  16 // An observer API implemented by classes which are interested
  17 // in RenderProcessHost lifecycle events.
  18 class CONTENT_EXPORT RenderProcessHostObserver {
  19  public:
  20   // This method is invoked when the process is going to exit and should not be
  21   // used for further navigations. Note that this is a COURTESY callback, not
  22   // guaranteed to be called for any particular process. Because this is the
  23   // first step in an orderly shutdown of a render process, do not expect that
  24   // a new render process will be hosted with this RenderProcessHost.
  25   virtual void RenderProcessWillExit(RenderProcessHost* host) {}
  26
  27   // This method is invoked when the process of the observed RenderProcessHost
  28   // exits (either normally or with a crash). To determine if the process closed
  29   // normally or crashed, examine the |status| parameter.
  30   //
  31   // A new render process may be spawned for this RenderProcessHost, but there
  32   // are no guarantees (e.g. if shutdown is occurring, the HostDestroyed
  33   // callback will happen soon and that will be it, but if the renderer crashed
  34   // and the user clicks 'reload', a new render process will be spawned).
  35   //
  36   // This will cause a call to WebContentsObserver::RenderProcessGone() for the
  37   // active renderer process for the top-level frame; for code that needs to be
  38   // a WebContentsObserver anyway, consider whether that API might be a better
  39   // choice.
  40   virtual void RenderProcessExited(RenderProcessHost* host,
  41                                    base::TerminationStatus status,
  42                                    int exit_code) {}
  43
  44   // This method is invoked when the observed RenderProcessHost itself is
  45   // destroyed. This is guaranteed to be the last call made to the observer, so
  46   // if the observer is tied to the observed RenderProcessHost, it is safe to
  47   // delete it.
  48   virtual void RenderProcessHostDestroyed(RenderProcessHost* host) {}
  49
  50  protected:
  51   virtual ~RenderProcessHostObserver() {}
  52 };
  53
  54 }  // namespace content
  55
  56 #endif  // CONTENT_PUBLIC_BROWSER_RENDER_PROCESS_HOST_OBSERVER_H_