gecko-dev/netwerk/base/nsBufferedStreams.h
Emilio Cobos Álvarez 74327c26b4 Bug 1599615 - Make some necko code less nsresult-happy. r=kershaw,valentin
Stuff that's infallible and not virtual has no reason to return an nsresult.

Differential Revision: https://phabricator.services.mozilla.com/D54831

--HG--
extra : moz-landing-system : lando
2019-12-02 13:21:06 +00:00

168 lines
5.8 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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 nsBufferedStreams_h__
#define nsBufferedStreams_h__
#include "nsIBufferedStreams.h"
#include "nsIInputStream.h"
#include "nsIOutputStream.h"
#include "nsISafeOutputStream.h"
#include "nsISeekableStream.h"
#include "nsIStreamBufferAccess.h"
#include "nsCOMPtr.h"
#include "nsIIPCSerializableInputStream.h"
#include "nsIAsyncInputStream.h"
#include "nsICloneableInputStream.h"
#include "nsIInputStreamLength.h"
#include "mozilla/Mutex.h"
////////////////////////////////////////////////////////////////////////////////
class nsBufferedStream : public nsISeekableStream {
public:
NS_DECL_THREADSAFE_ISUPPORTS
NS_DECL_NSISEEKABLESTREAM
NS_DECL_NSITELLABLESTREAM
nsBufferedStream();
void Close();
protected:
virtual ~nsBufferedStream();
nsresult Init(nsISupports* stream, uint32_t bufferSize);
nsresult GetData(nsISupports** aResult);
NS_IMETHOD Fill() = 0;
NS_IMETHOD Flush() = 0;
uint32_t mBufferSize;
char* mBuffer;
// mBufferStartOffset is the offset relative to the start of mStream.
int64_t mBufferStartOffset;
// mCursor is the read cursor for input streams, or write cursor for
// output streams, and is relative to mBufferStartOffset.
uint32_t mCursor;
// mFillPoint is the amount available in the buffer for input streams,
// or the high watermark of bytes written into the buffer, and therefore
// is relative to mBufferStartOffset.
uint32_t mFillPoint;
nsCOMPtr<nsISupports> mStream; // cast to appropriate subclass
bool mBufferDisabled;
bool mEOF; // True if mStream is at EOF
uint8_t mGetBufferCount;
};
////////////////////////////////////////////////////////////////////////////////
class nsBufferedInputStream final : public nsBufferedStream,
public nsIBufferedInputStream,
public nsIStreamBufferAccess,
public nsIIPCSerializableInputStream,
public nsIAsyncInputStream,
public nsIInputStreamCallback,
public nsICloneableInputStream,
public nsIInputStreamLength,
public nsIAsyncInputStreamLength,
public nsIInputStreamLengthCallback {
public:
NS_DECL_ISUPPORTS_INHERITED
NS_DECL_NSIINPUTSTREAM
NS_DECL_NSIBUFFEREDINPUTSTREAM
NS_DECL_NSISTREAMBUFFERACCESS
NS_DECL_NSIIPCSERIALIZABLEINPUTSTREAM
NS_DECL_NSIASYNCINPUTSTREAM
NS_DECL_NSIINPUTSTREAMCALLBACK
NS_DECL_NSICLONEABLEINPUTSTREAM
NS_DECL_NSIINPUTSTREAMLENGTH
NS_DECL_NSIASYNCINPUTSTREAMLENGTH
NS_DECL_NSIINPUTSTREAMLENGTHCALLBACK
nsBufferedInputStream();
static nsresult Create(nsISupports* aOuter, REFNSIID aIID, void** aResult);
nsIInputStream* Source() { return (nsIInputStream*)mStream.get(); }
/**
* If there's a reference/pointer to an nsBufferedInputStream BEFORE calling
* Init() AND the intent is to ultimately convert/assign that
* reference/pointer to an nsIInputStream, DO NOT use that initial
* reference/pointer. Instead, use the value of QueryInterface-ing to an
* nsIInputStream (and, again, the QueryInterface must be performed after
* Init()). This is because nsBufferedInputStream has multiple underlying
* nsIInputStreams (one from nsIBufferedInputStream and one from
* nsIAsyncInputStream), and the correct base nsIInputStream to use will be
* unknown until the final value of mIsAsyncInputStream is set in Init().
*
* This method, however, does just that but also hides the QI details and
* will assert if called before Init().
*/
already_AddRefed<nsIInputStream> GetInputStream();
protected:
virtual ~nsBufferedInputStream() = default;
template <typename M>
void SerializeInternal(mozilla::ipc::InputStreamParams& aParams,
FileDescriptorArray& aFileDescriptors,
bool aDelayedStart, uint32_t aMaxSize,
uint32_t* aSizeUsed, M* aManager);
NS_IMETHOD Fill() override;
NS_IMETHOD Flush() override { return NS_OK; } // no-op for input streams
mozilla::Mutex mMutex;
// This value is protected by mutex.
nsCOMPtr<nsIInputStreamCallback> mAsyncWaitCallback;
// This value is protected by mutex.
nsCOMPtr<nsIInputStreamLengthCallback> mAsyncInputStreamLengthCallback;
bool mIsIPCSerializable;
bool mIsAsyncInputStream;
bool mIsCloneableInputStream;
bool mIsInputStreamLength;
bool mIsAsyncInputStreamLength;
};
////////////////////////////////////////////////////////////////////////////////
class nsBufferedOutputStream : public nsBufferedStream,
public nsISafeOutputStream,
public nsIBufferedOutputStream,
public nsIStreamBufferAccess {
public:
NS_DECL_ISUPPORTS_INHERITED
NS_DECL_NSIOUTPUTSTREAM
NS_DECL_NSISAFEOUTPUTSTREAM
NS_DECL_NSIBUFFEREDOUTPUTSTREAM
NS_DECL_NSISTREAMBUFFERACCESS
nsBufferedOutputStream() : nsBufferedStream() {}
static nsresult Create(nsISupports* aOuter, REFNSIID aIID, void** aResult);
nsIOutputStream* Sink() { return (nsIOutputStream*)mStream.get(); }
protected:
virtual ~nsBufferedOutputStream() { nsBufferedOutputStream::Close(); }
NS_IMETHOD Fill() override { return NS_OK; } // no-op for output streams
nsCOMPtr<nsISafeOutputStream> mSafeStream; // QI'd from mStream
};
////////////////////////////////////////////////////////////////////////////////
#endif // nsBufferedStreams_h__