/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 *
 * The contents of this file are subject to the Netscape Public License
 * Version 1.0 (the "NPL"); you may not use this file except in
 * compliance with the NPL.  You may obtain a copy of the NPL at
 * http://www.mozilla.org/NPL/
 *
 * Software distributed under the NPL is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
 * for the specific language governing rights and limitations under the
 * NPL.
 *
 * The Initial Developer of this code under the NPL is Netscape
 * Communications Corporation.  Portions created by Netscape are
 * Copyright (C) 1998 Netscape Communications Corporation.  All Rights
 * Reserved.
 */

#ifndef nsIOutputStream_h___
#define nsIOutputStream_h___

#include "nsIBaseStream.h"

class nsIInputStream;

/* 7f13b870-e95f-11d1-beae-00805f8a66dc */
#define NS_IOUTPUTSTREAM_IID   \
{ 0x7f13b870, 0xe95f, 0x11d1, \
  {0xbe, 0xae, 0x00, 0x80, 0x5f, 0x8a, 0x66, 0xdc} }

/** Abstract byte output stream */
class nsIOutputStream : public nsIBaseStream {
public:

    static const nsIID& GetIID() { static nsIID iid = NS_IOUTPUTSTREAM_IID; return iid; }

    /** Write data into the stream.
     *  @param aBuf the buffer from which the data is read
     *  @param aCount the maximum number of bytes to write
     *  @param aWriteCount out parameter to hold the number of
     *         bytes written. if an error occurs, the writecount
     *         is undefined
     *  @return error status
     */   
    NS_IMETHOD
    Write(const char* aBuf, PRUint32 aCount, PRUint32 *aWriteCount) = 0; 

    /**
     * Writes data into the stream from an input stream.
     * Implementer's note: This method is defined by this interface in order
     * to allow the output stream to efficiently copy the data from the input
     * stream into its internal buffer (if any). If this method was provide
     * as an external facility, a separate char* buffer would need to be used
     * in order to call the output stream's other Write method.
     * @param fromStream the stream from which the data is read
     * @param aWriteCount out parameter to hold the number of
     *         bytes written. if an error occurs, the writecount
     *         is undefined
     *  @return error status
     */
    NS_IMETHOD
    Write(nsIInputStream* fromStream, PRUint32 *aWriteCount) = 0;

    /**
     * Flushes the stream.
     */
    NS_IMETHOD
    Flush(void) = 0;

};


#endif /* nsOutputStream_h___ */