gecko/dom/cache/ReadStream.h

113 lines
3.4 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef mozilla_dom_cache_ReadStream_h
#define mozilla_dom_cache_ReadStream_h
#include "mozilla/ipc/FileDescriptor.h"
#include "nsCOMPtr.h"
#include "nsID.h"
#include "nsIInputStream.h"
#include "nsISupportsImpl.h"
#include "mozilla/nsRefPtr.h"
#include "nsTArrayForwardDeclare.h"
namespace mozilla {
namespace dom {
namespace cache {
class CacheReadStream;
class CacheReadStreamOrVoid;
class PCacheStreamControlParent;
// IID for the dom::cache::ReadStream interface
#define NS_DOM_CACHE_READSTREAM_IID \
{0x8e5da7c9, 0x0940, 0x4f1d, \
{0x97, 0x25, 0x5c, 0x59, 0x38, 0xdd, 0xb9, 0x9f}}
// Custom stream class for Request and Response bodies being read from
// a Cache. The main purpose of this class is to report back to the
// Cache's Manager when the stream is closed. This allows the Cache to
// accurately determine when the underlying body file can be deleted,
// etc.
//
// The ReadStream class also provides us with a convenient QI'able
// interface that we can use to pass additional meta-data with the
// stream channel. For example, Cache.put() can detect that the content
// script is passing a Cache-originated-stream back into the Cache
// again. This enables certain optimizations.
class ReadStream final : public nsIInputStream
{
public:
// Interface that lets the StreamControl classes interact with
// our private inner stream.
class Controllable
{
public:
// Closes the stream, notifies the stream control, and then forgets
// the stream control.
virtual void
CloseStream() = 0;
// Closes the stream and then forgets the stream control. Does not
// notify.
virtual void
CloseStreamWithoutReporting() = 0;
virtual bool
MatchId(const nsID& aId) const = 0;
virtual bool
HasEverBeenRead() const = 0;
NS_IMETHOD_(MozExternalRefCountType)
AddRef(void) = 0;
NS_IMETHOD_(MozExternalRefCountType)
Release(void) = 0;
};
static already_AddRefed<ReadStream>
Create(const CacheReadStreamOrVoid& aReadStreamOrVoid);
static already_AddRefed<ReadStream>
Create(const CacheReadStream& aReadStream);
static already_AddRefed<ReadStream>
Create(PCacheStreamControlParent* aControl, const nsID& aId,
nsIInputStream* aStream);
void Serialize(CacheReadStreamOrVoid* aReadStreamOut);
void Serialize(CacheReadStream* aReadStreamOut);
private:
class Inner;
explicit ReadStream(Inner* aInner);
~ReadStream();
// Hold a strong ref to an inner class that actually implements the
// majority of the stream logic. Before releasing this ref the outer
// ReadStream guarantees it will call Close() on the inner stream.
// This is essential for the inner stream to avoid dealing with the
// implicit close that can happen when a stream is destroyed.
nsRefPtr<Inner> mInner;
public:
NS_DECLARE_STATIC_IID_ACCESSOR(NS_DOM_CACHE_READSTREAM_IID);
NS_DECL_THREADSAFE_ISUPPORTS
NS_DECL_NSIINPUTSTREAM
};
NS_DEFINE_STATIC_IID_ACCESSOR(ReadStream, NS_DOM_CACHE_READSTREAM_IID);
} // namespace cache
} // namespace dom
} // namespace mozilla
#endif // mozilla_dom_cache_ReadStream_h