gecko-dev/xpcom/io/nsStreamUtils.h

112 lines
4.5 KiB
C++

/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Mozilla.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 2002
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Darin Fisher <darin@netscape.com>
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#ifndef nsStreamUtils_h__
#define nsStreamUtils_h__
#include "nscore.h"
class nsIInputStream;
class nsIOutputStream;
class nsIInputStreamCallback;
class nsIOutputStreamCallback;
class nsIEventTarget;
/**
* A "one-shot" proxy of the OnInputStreamReady callback. The resulting
* proxy object's OnInputStreamReady function may only be called once! The
* proxy object ensures that the real notify object will be free'd on the
* thread corresponding to the given event target regardless of what thread
* the proxy object is destroyed on.
*
* This function is designed to be used to implement AsyncWait when the
* aEventTarget parameter is non-null.
*/
extern NS_COM nsresult
NS_NewInputStreamReadyEvent(nsIInputStreamCallback **aEvent,
nsIInputStreamCallback *aNotify,
nsIEventTarget *aEventTarget);
/**
* A "one-shot" proxy of the OnOutputStreamReady callback. The resulting
* proxy object's OnOutputStreamReady function may only be called once! The
* proxy object ensures that the real notify object will be free'd on the
* thread corresponding to the given event target regardless of what thread
* the proxy object is destroyed on.
*
* This function is designed to be used to implement AsyncWait when the
* aEventTarget parameter is non-null.
*/
extern NS_COM nsresult
NS_NewOutputStreamReadyEvent(nsIOutputStreamCallback **aEvent,
nsIOutputStreamCallback *aNotify,
nsIEventTarget *aEventTarget);
/* ------------------------------------------------------------------------- */
enum nsAsyncCopyMode {
NS_ASYNCCOPY_VIA_READSEGMENTS,
NS_ASYNCCOPY_VIA_WRITESEGMENTS
};
/**
* This function is called when the async copy process completes. The reported
* status is NS_OK on success and some error code on failure.
*/
typedef void (* nsAsyncCopyCallbackFun)(void *closure, nsresult status);
/**
* This function asynchronously copies data from the source to the sink. All
* data transfer occurs on the thread corresponding to the given event target.
* A null event target is not permitted.
*
* The copier handles blocking or non-blocking streams transparently. If a
* stream operation returns NS_BASE_STREAM_WOULD_BLOCK, then the stream will
* be QI'd to nsIAsync{In,Out}putStream and its AsyncWait method will be used
* to determine when to resume copying.
*/
extern NS_COM nsresult
NS_AsyncCopy(nsIInputStream *aSource,
nsIOutputStream *aSink,
nsIEventTarget *aEventTarget,
nsAsyncCopyMode aMode = NS_ASYNCCOPY_VIA_READSEGMENTS,
PRUint32 aChunkSize = 4096,
nsAsyncCopyCallbackFun aCallbackFun = nsnull,
void *aCallbackClosure = nsnull);
#endif // !nsStreamUtils_h__