dom/workers/WorkerFeature.h

   1 /* -*- Mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; tab-width: 40 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #ifndef mozilla_dom_workers_workerfeature_h__
   7 #define mozilla_dom_workers_workerfeature_h__
   8
   9 #include "mozilla/dom/workers/Workers.h"
  10
  11 BEGIN_WORKERS_NAMESPACE
  12
  13 /**
  14  * Use this chart to help figure out behavior during each of the closing
  15  * statuses. Details below.
  16  *
  17  * +==============================================================+
  18  * |                       Closing Statuses                       |
  19  * +=============+=============+=================+================+
  20  * |    status   | clear queue | abort execution |  close handler |
  21  * +=============+=============+=================+================+
  22  * |   Closing   |     yes     |       no        |   no timeout   |
  23  * +-------------+-------------+-----------------+----------------+
  24  * | Terminating |     yes     |       yes       |   no timeout   |
  25  * +-------------+-------------+-----------------+----------------+
  26  * |  Canceling  |     yes     |       yes       | short duration |
  27  * +-------------+-------------+-----------------+----------------+
  28  * |   Killing   |     yes     |       yes       |   doesn't run  |
  29  * +-------------+-------------+-----------------+----------------+
  30  */
  31
  32 #ifdef Status
  33 /* Xlib headers insist on this for some reason... Nuke it because
  34    it'll override our member name */
  35 #undef Status
  36 #endif
  37 enum Status
  38 {
  39   // Not yet scheduled.
  40   Pending = 0,
  41
  42   // This status means that the close handler has not yet been scheduled.
  43   Running,
  44
  45   // Inner script called close() on the worker global scope. Setting this
  46   // status causes the worker to clear its queue of events but does not abort
  47   // the currently running script. The close handler is also scheduled with
  48   // no expiration time.
  49   Closing,
  50
  51   // Outer script called terminate() on the worker or the worker object was
  52   // garbage collected in its outer script. Setting this status causes the
  53   // worker to abort immediately, clear its queue of events, and schedules the
  54   // close handler with no expiration time.
  55   Terminating,
  56
  57   // Either the user navigated away from the owning page or the owning page fell
  58   // out of bfcache. Setting this status causes the worker to abort immediately
  59   // and schedules the close handler with a short expiration time. Since the
  60   // page has gone away the worker may not post any messages.
  61   Canceling,
  62
  63   // The application is shutting down. Setting this status causes the worker to
  64   // abort immediately and the close handler is never scheduled.
  65   Killing,
  66
  67   // The close handler has run and the worker is effectively dead.
  68   Dead
  69 };
  70
  71 class WorkerFeature
  72 {
  73 public:
  74   virtual ~WorkerFeature() { }
  75
  76   virtual bool Suspend(JSContext* aCx) { return true; }
  77   virtual bool Resume(JSContext* aCx) { return true; }
  78
  79   virtual bool Notify(JSContext* aCx, Status aStatus) = 0;
  80 };
  81
  82 END_WORKERS_NAMESPACE
  83
  84 #endif /* mozilla_dom_workers_workerfeature_h__ */