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 --- xpcom/io/nsIAsyncOutputStream.idl | 104 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 104 insertions(+) create mode 100644 xpcom/io/nsIAsyncOutputStream.idl (limited to 'xpcom/io/nsIAsyncOutputStream.idl') diff --git a/xpcom/io/nsIAsyncOutputStream.idl b/xpcom/io/nsIAsyncOutputStream.idl new file mode 100644 index 000000000..7e74579c6 --- /dev/null +++ b/xpcom/io/nsIAsyncOutputStream.idl @@ -0,0 +1,104 @@ +/* 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/. */ + +#include "nsIOutputStream.idl" + +interface nsIOutputStreamCallback; +interface nsIEventTarget; + +/** + * If an output stream is non-blocking, it may return NS_BASE_STREAM_WOULD_BLOCK + * when written to. The caller must then wait for the stream to become + * writable. If the stream implements nsIAsyncOutputStream, then the caller can + * use this interface to request an asynchronous notification when the stream + * becomes writable or closed (via the AsyncWait method). + * + * While this interface is almost exclusively used with non-blocking streams, it + * is not necessary that nsIOutputStream::isNonBlocking return true. Nor is it + * necessary that a non-blocking nsIOutputStream implementation also implement + * nsIAsyncOutputStream. + */ +[scriptable, uuid(beb632d3-d77a-4e90-9134-f9ece69e8200)] +interface nsIAsyncOutputStream : nsIOutputStream +{ + /** + * This method closes the stream and sets its internal status. If the + * stream is already closed, then this method is ignored. Once the stream + * is closed, the stream's status cannot be changed. Any successful status + * code passed to this method is treated as NS_BASE_STREAM_CLOSED, which + * is equivalent to nsIInputStream::close. + * + * NOTE: this method exists in part to support pipes, which have both an + * input end and an output end. If the output end of a pipe is closed, then + * reads from the input end of the pipe will fail. The error code returned + * when an attempt is made to read from a "closed" pipe corresponds to the + * status code passed in when the output end of the pipe is closed, which + * greatly simplifies working with pipes in some cases. + * + * @param aStatus + * The error that will be reported if this stream is accessed after + * it has been closed. + */ + void closeWithStatus(in nsresult reason); + + /** + * Asynchronously wait for the stream to be writable or closed. The + * notification is one-shot, meaning that each asyncWait call will result + * in exactly one notification callback. After the OnOutputStreamReady event + * is dispatched, the stream releases its reference to the + * nsIOutputStreamCallback object. It is safe to call asyncWait again from the + * notification handler. + * + * This method may be called at any time (even if write has not been called). + * In other words, this method may be called when the stream already has + * room for more data. It may also be called when the stream is closed. If + * the stream is already writable or closed when AsyncWait is called, then the + * OnOutputStreamReady event will be dispatched immediately. Otherwise, the + * event will be dispatched when the stream becomes writable or closed. + * + * @param aCallback + * This object is notified when the stream becomes ready. This + * parameter may be null to clear an existing callback. + * @param aFlags + * This parameter specifies optional flags passed in to configure + * the behavior of this method. Pass zero to specify no flags. + * @param aRequestedCount + * Wait until at least this many bytes can be written. This is only + * a suggestion to the underlying stream; it may be ignored. The + * caller may pass zero to indicate no preference. + * @param aEventTarget + * Specify NULL to receive notification on ANY thread (possibly even + * recursively on the calling thread -- i.e., synchronously), or + * specify that the notification be delivered to a specific event + * target. + */ + void asyncWait(in nsIOutputStreamCallback aCallback, + in unsigned long aFlags, + in unsigned long aRequestedCount, + in nsIEventTarget aEventTarget); + + /** + * If passed to asyncWait, this flag overrides the default behavior, + * causing the OnOutputStreamReady notification to be suppressed until the + * stream becomes closed (either as a result of closeWithStatus/close being + * called on the stream or possibly due to some error in the underlying + * stream). + */ + const unsigned long WAIT_CLOSURE_ONLY = (1<<0); +}; + +/** + * This is a companion interface for nsIAsyncOutputStream::asyncWait. + */ +[function, scriptable, uuid(40dbcdff-9053-42c5-a57c-3ec910d0f148)] +interface nsIOutputStreamCallback : nsISupports +{ + /** + * Called to indicate that the stream is either writable or closed. + * + * @param aStream + * The stream whose asyncWait method was called. + */ + void onOutputStreamReady(in nsIAsyncOutputStream aStream); +}; -- cgit v1.2.3