From 5f8de423f190bbb79a62f804151bc24824fa32d8 Mon Sep 17 00:00:00 2001 From: "Matt A. Tobin" Date: Fri, 2 Feb 2018 04:16:08 -0500 Subject: Add m-esr52 at 52.6.0 --- netwerk/base/nsBaseContentStream.h | 82 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 82 insertions(+) create mode 100644 netwerk/base/nsBaseContentStream.h (limited to 'netwerk/base/nsBaseContentStream.h') diff --git a/netwerk/base/nsBaseContentStream.h b/netwerk/base/nsBaseContentStream.h new file mode 100644 index 000000000..992c8733e --- /dev/null +++ b/netwerk/base/nsBaseContentStream.h @@ -0,0 +1,82 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ +/* 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 nsBaseContentStream_h__ +#define nsBaseContentStream_h__ + +#include "nsIAsyncInputStream.h" +#include "nsIEventTarget.h" +#include "nsCOMPtr.h" + +//----------------------------------------------------------------------------- +// nsBaseContentStream is designed to be subclassed with the intention of being +// used to satisfy the nsBaseChannel::OpenContentStream method. +// +// The subclass typically overrides the default Available, ReadSegments and +// CloseWithStatus methods. By default, Read is implemented in terms of +// ReadSegments, and Close is implemented in terms of CloseWithStatus. If +// CloseWithStatus is overriden, then the subclass will usually want to call +// the base class' CloseWithStatus method before returning. +// +// If the stream is non-blocking, then readSegments may return the exception +// NS_BASE_STREAM_WOULD_BLOCK if there is no data available and the stream is +// not at the "end-of-file" or already closed. This error code must not be +// returned from the Available implementation. When the caller receives this +// error code, he may choose to call the stream's AsyncWait method, in which +// case the base stream will have a non-null PendingCallback. When the stream +// has data or encounters an error, it should be sure to dispatch a pending +// callback if one exists (see DispatchCallback). The implementation of the +// base stream's CloseWithStatus (and Close) method will ensure that any +// pending callback is dispatched. It is the responsibility of the subclass +// to ensure that the pending callback is dispatched when it wants to have its +// ReadSegments method called again. + +class nsBaseContentStream : public nsIAsyncInputStream +{ +public: + NS_DECL_THREADSAFE_ISUPPORTS + NS_DECL_NSIINPUTSTREAM + NS_DECL_NSIASYNCINPUTSTREAM + + explicit nsBaseContentStream(bool nonBlocking) + : mStatus(NS_OK) + , mNonBlocking(nonBlocking) { + } + + nsresult Status() { return mStatus; } + bool IsNonBlocking() { return mNonBlocking; } + bool IsClosed() { return NS_FAILED(mStatus); } + + // Called to test if the stream has a pending callback. + bool HasPendingCallback() { return mCallback != nullptr; } + + // The current dispatch target (may be null) for the pending callback if any. + nsIEventTarget *CallbackTarget() { return mCallbackTarget; } + + // Called to dispatch a pending callback. If there is no pending callback, + // then this function does nothing. Pass true to this function to cause the + // callback to occur asynchronously; otherwise, the callback will happen + // before this function returns. + void DispatchCallback(bool async = true); + + // Helper function to make code more self-documenting. + void DispatchCallbackSync() { DispatchCallback(false); } + +protected: + virtual ~nsBaseContentStream() {} + +private: + // Called from the base stream's AsyncWait method when a pending callback + // is installed on the stream. + virtual void OnCallbackPending() {} + +private: + nsCOMPtr mCallback; + nsCOMPtr mCallbackTarget; + nsresult mStatus; + bool mNonBlocking; +}; + +#endif // nsBaseContentStream_h__ -- cgit v1.2.3