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/* ***** BEGIN LICENSE BLOCK *****
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* Version: MPL 1.1/GPL 2.0/LGPL 2.1
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* The contents of this file are subject to the Mozilla Public License Version
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* 1.1 (the "License"); you may not use this file except in compliance with
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* the License. You may obtain a copy of the License at
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* http://www.mozilla.org/MPL/
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* Software distributed under the License is distributed on an "AS IS" basis,
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* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
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* for the specific language governing rights and limitations under the
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* The Original Code is Mozilla.
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* The Initial Developer of the Original Code is
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* Netscape Communications Corporation.
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* Portions created by the Initial Developer are Copyright (C) 2002
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* the Initial Developer. All Rights Reserved.
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* Darin Fisher <darin@netscape.com>
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* Alternatively, the contents of this file may be used under the terms of
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* either the GNU General Public License Version 2 or later (the "GPL"), or
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* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
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* in which case the provisions of the GPL or the LGPL are applicable instead
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* of those above. If you wish to allow use of your version of this file only
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* under the terms of either the GPL or the LGPL, and not to allow others to
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* use your version of this file under the terms of the MPL, indicate your
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* decision by deleting the provisions above and replace them with the notice
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* and other provisions required by the GPL or the LGPL. If you do not delete
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* the provisions above, a recipient may use your version of this file under
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* the terms of any one of the MPL, the GPL or the LGPL.
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* ***** END LICENSE BLOCK ***** */
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#include "nsIOutputStream.idl"
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interface nsIOutputStreamCallback;
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interface nsIEventTarget;
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* If an output stream is non-blocking, it may return NS_BASE_STREAM_WOULD_BLOCK
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* when written to. The caller must then wait for the stream to become
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* writable. If the stream implements nsIAsyncOutputStream, then the caller can
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* use this interface to request an asynchronous notification when the stream
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* becomes writable or closed (via the AsyncWait method).
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* While this interface is almost exclusively used with non-blocking streams, it
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* is not necessary that nsIOutputStream::isNonBlocking return true. Nor is it
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* necessary that a non-blocking nsIOutputStream implementation also implement
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* nsIAsyncOutputStream.
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[scriptable, uuid(10dc9c94-8aff-49c6-8af9-d7fdb7339dae)]
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interface nsIAsyncOutputStream : nsIOutputStream
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* This method closes the stream and sets its internal status. If the
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* stream is already closed, then this method is ignored. Once the stream
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* is closed, the stream's status cannot be changed. Any successful status
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* code passed to this method is treated as NS_BASE_STREAM_CLOSED, which
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* is equivalent to nsIInputStream::close.
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* NOTE: this method exists in part to support pipes, which have both an
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* input end and an output end. If the output end of a pipe is closed, then
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* reads from the input end of the pipe will fail. The error code returned
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* when an attempt is made to read from a "closed" pipe corresponds to the
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* status code passed in when the output end of the pipe is closed, which
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* greatly simplifies working with pipes in some cases.
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* The error that will be reported if this stream is accessed after
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void closeWithStatus(in nsresult reason);
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* Asynchronously wait for the stream to be writable or closed. The
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* notification is one-shot, meaning that each asyncWait call will result
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* in exactly one notification callback. After the OnOutputStreamReady event
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* is dispatched, the stream releases its reference to the
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* nsIOutputStreamCallback object. It is safe to call asyncWait again from the
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* notification handler.
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* This method may be called at any time (even if write has not been called).
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* In other words, this method may be called when the stream already has
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* room for more data. It may also be called when the stream is closed. If
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* the stream is already writable or closed when AsyncWait is called, then the
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* OnOutputStreamReady event will be dispatched immediately. Otherwise, the
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* event will be dispatched when the stream becomes writable or closed.
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* This object is notified when the stream becomes ready.
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* This parameter specifies optional flags passed in to configure
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* the behavior of this method. Pass zero to specify no flags.
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* @param aRequestedCount
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* Wait until at least this many bytes can be written. This is only
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* a suggestion to the underlying stream; it may be ignored. The
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* caller may pass zero to indicate no preference.
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* @param aEventTarget
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* Specify NULL to receive notification on ANY thread (possibly even
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* recursively on the calling thread -- i.e., synchronously), or
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* specify that the notification be delivered to a specific event
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void asyncWait(in nsIOutputStreamCallback aCallback,
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in unsigned long aFlags,
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in unsigned long aRequestedCount,
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in nsIEventTarget aEventTarget);
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* If passed to asyncWait, this flag overrides the default behavior,
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* causing the OnOutputStreamReady notification to be suppressed until the
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* stream becomes closed (either as a result of closeWithStatus/close being
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* called on the stream or possibly due to some error in the underlying
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const unsigned long WAIT_CLOSURE_ONLY = (1<<0);
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* This is a companion interface for nsIAsyncOutputStream::asyncWait.
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[scriptable, uuid(40dbcdff-9053-42c5-a57c-3ec910d0f148)]
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interface nsIOutputStreamCallback : nsISupports
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* Called to indicate that the stream is either writable or closed.
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* The stream whose asyncWait method was called.
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void onOutputStreamReady(in nsIAsyncOutputStream aStream);