third_party/blink/renderer/core/loader/frame_loader_state_machine.h

/*
 * Copyright (C) 2010 Google Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 * 2.  Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 * 3.  Neither the name of Google, Inc. nor the names of
 *     its contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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#ifndef THIRD_PARTY_BLINK_RENDERER_CORE_LOADER_FRAME_LOADER_STATE_MACHINE_H_
#define THIRD_PARTY_BLINK_RENDERER_CORE_LOADER_FRAME_LOADER_STATE_MACHINE_H_

#include "base/macros.h"
#include "third_party/blink/renderer/core/core_export.h"
#include "third_party/blink/renderer/platform/wtf/allocator.h"
#include "third_party/blink/renderer/platform/wtf/text/wtf_string.h"

namespace blink {

// Encapsulates a state machine for FrameLoader. Note that this is different
// from FrameState, which stores the state of the current load that FrameLoader
// is executing.
class CORE_EXPORT FrameLoaderStateMachine {
  DISALLOW_NEW();

 public:
  FrameLoaderStateMachine();

  // Once a load has been committed, the state may alternate between
  // CommittedFirstRealLoad and FirstLayoutDone. Otherwise, the states only go
  // down the list.
  enum State {
    kCreatingInitialEmptyDocument,
    kDisplayingInitialEmptyDocument,
    kCommittedFirstRealLoad,
    kCommittedMultipleRealLoads
  };

  bool CommittedFirstRealDocumentLoad() const;
  bool CreatingInitialEmptyDocument() const;
  bool IsDisplayingInitialEmptyDocument() const;
  bool CommittedMultipleRealLoads() const;
  void AdvanceTo(State);

  String ToString() const;

 private:
  State state_;

  DISALLOW_COPY_AND_ASSIGN(FrameLoaderStateMachine);
};

}  // namespace blink

#endif  // THIRD_PARTY_BLINK_RENDERER_CORE_LOADER_FRAME_LOADER_STATE_MACHINE_H_