/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 *
 * 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 nsIByteBuffer_h___
#define nsIByteBuffer_h___

#include "nscore.h"
#include "nsISupports.h"

class nsIInputStream;

#define NS_IBYTE_BUFFER_IID    \
{ 0xe4a6e4b0, 0x93b4, 0x11d1, \
  {0x89, 0x5b, 0x00, 0x60, 0x08, 0x91, 0x1b, 0x81} }

/** Interface to a buffer that holds bytes */
class nsIByteBuffer : public nsISupports {
public:
  /** @return length of buffer, i.e. how many bytes are currently in it. */
  virtual PRInt32 GetLength() const = 0;

  /** @return number of bytes allocated in the buffer */
  virtual PRInt32 GetBufferSize() const = 0;

  /** @return the buffer */
  virtual char* GetBuffer() const = 0;

  /** Grow buffer to aNewSize bytes. */
  virtual PRBool Grow(PRInt32 aNewSize) = 0;

  /** Fill the buffer with data from aStream.  Don't grow the buffer, only
   *  read until length of buffer equals buffer size. */
  virtual PRInt32 Fill(PRInt32* aErrorCode, nsIInputStream* aStream,
                       PRInt32 aKeep) = 0;
};

/** Create a new byte buffer using the given buffer size. */
extern NS_BASE nsresult NS_NewByteBuffer(nsIByteBuffer** aInstancePtrResult,
                                         nsISupports* aOuter,
                                         PRInt32 aBufferSize = 0);

#endif /* nsIByteBuffer_h___ */
