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 {
  27     DEFINE_WRAPPERTYPEINFO();
  28 public:
  29     enum State {
  30         Readable,
  31         Waiting,
  32         Closed,
  33         Errored,
  34     };
  35
  36     // FIXME: Define Strategy here.
  37     // FIXME: Add |strategy| constructor parameter.
  38     // After ReadableStream construction, |didSourceStart| must be called when
  39     // |source| initialization succeeds and |error| must be called when
  40     // |source| initialization fails.
  41     ReadableStream(ExecutionContext*, UnderlyingSource* /* source */);
  42     virtual ~ReadableStream();
  43
  44     bool isStarted() const { return m_isStarted; }
  45     bool isDraining() const { return m_isDraining; }
  46     bool isPulling() const { return m_isPulling; }
  47     State state() const { return m_state; }
  48     String stateString() const;
  49
  50     virtual ScriptValue read(ScriptState*, ExceptionState&) = 0;
  51     ScriptPromise wait(ScriptState*);
  52     ScriptPromise cancel(ScriptState*, ScriptValue reason);
  53     ScriptPromise closed(ScriptState*);
  54
  55     void close();
  56     void error(PassRefPtrWillBeRawPtr<DOMException>);
  57
  58     void didSourceStart();
  59
  60     virtual void trace(Visitor*);
  61
  62 protected:
  63     bool enqueuePreliminaryCheck(size_t chunkSize);
  64     bool enqueuePostAction(size_t totalQueueSize);
  65     void readPreliminaryCheck(ExceptionState&);
  66     void readPostAction();
  67
  68 private:
  69     typedef ScriptPromiseProperty<Member<ReadableStream>, V8UndefinedType, RefPtrWillBeMember<DOMException> > WaitPromise;
  70     typedef ScriptPromiseProperty<Member<ReadableStream>, V8UndefinedType, RefPtrWillBeMember<DOMException> > ClosedPromise;
  71
  72     virtual bool isQueueEmpty() const = 0;
  73     virtual void clearQueue() = 0;
  74
  75     void callOrSchedulePull();
  76
  77     Member<UnderlyingSource> m_source;
  78     bool m_isStarted;
  79     bool m_isDraining;
  80     bool m_isPulling;
  81     bool m_isSchedulingPull;
  82     State m_state;
  83
  84     Member<WaitPromise> m_wait;
  85     Member<ClosedPromise> m_closed;
  86     RefPtrWillBeMember<DOMException> m_exception;
  87 };
  88
  89 } // namespace blink
  90
  91 #endif // ReadableStream_h