src/third_party/WebKit/Source/core/streams/ReadableStream.h

   1 // Copyright 2014 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 ReadableStream_h
   6 #define ReadableStream_h
   7
   8 #include "bindings/core/v8/ScriptPromise.h"
   9 #include "bindings/core/v8/ScriptPromiseProperty.h"
  10 #include "bindings/core/v8/ScriptState.h"
  11 #include "bindings/core/v8/ScriptValue.h"
  12 #include "bindings/core/v8/ScriptWrappable.h"
  13 #include "bindings/core/v8/V8Binding.h"
  14 #include "core/dom/ContextLifecycleObserver.h"
  15 #include "platform/heap/Handle.h"
  16 #include "wtf/Forward.h"
  17 #include "wtf/PassRefPtr.h"
  18 #include "wtf/RefPtr.h"
  19
  20 namespace blink {
  21
  22 class DOMException;
  23 class ExceptionState;
  24 class UnderlyingSource;
  25
  26 class ReadableStream : public GarbageCollectedFinalized<ReadableStream>, public ScriptWrappable, public ContextLifecycleObserver {
  27 public:
  28     enum State {
  29         Readable,
  30         Waiting,
  31         Closed,
  32         Errored,
  33     };
  34
  35     // FIXME: Define Strategy here.
  36     // FIXME: Add |strategy| constructor parameter.
  37     ReadableStream(ScriptState*, UnderlyingSource*, ExceptionState*);
  38     virtual ~ReadableStream();
  39
  40     bool isStarted() const { return m_isStarted; }
  41     bool isDraining() const { return m_isDraining; }
  42     bool isPulling() const { return m_isPulling; }
  43     State state() const { return m_state; }
  44
  45     virtual ScriptValue read(ScriptState*, ExceptionState*) = 0;
  46     ScriptPromise wait(ScriptState*);
  47     ScriptPromise cancel(ScriptState*, ScriptValue reason);
  48     ScriptPromise closed(ScriptState*);
  49
  50     void close();
  51     void error(PassRefPtrWillBeRawPtr<DOMException>);
  52
  53     virtual void trace(Visitor*);
  54
  55 protected:
  56     bool enqueuePreliminaryCheck(size_t chunkSize);
  57     bool enqueuePostAction(size_t totalQueueSize);
  58     void readPreliminaryCheck(ExceptionState*);
  59     void readPostAction();
  60
  61 private:
  62     class OnStarted;
  63     typedef ScriptPromiseProperty<Member<ReadableStream>, V8UndefinedType, RefPtrWillBeMember<DOMException> > WaitPromise;
  64     typedef ScriptPromiseProperty<Member<ReadableStream>, V8UndefinedType, RefPtrWillBeMember<DOMException> > ClosedPromise;
  65
  66     virtual bool isQueueEmpty() const = 0;
  67     virtual void clearQueue() = 0;
  68
  69     void onStarted(void);
  70     void callOrSchedulePull();
  71
  72     Member<UnderlyingSource> m_source;
  73     bool m_isStarted;
  74     bool m_isDraining;
  75     bool m_isPulling;
  76     bool m_isSchedulingPull;
  77     State m_state;
  78
  79     Member<WaitPromise> m_wait;
  80     Member<ClosedPromise> m_closed;
  81     RefPtrWillBeMember<DOMException> m_exception;
  82 };
  83
  84 } // namespace blink
  85
  86 #endif // ReadableStream_h
  87