wstring_buffer.cpp

Windows CE 6.0 Server 源码

//
// Copyright (c) Microsoft Corporation.  All rights reserved.
//
//
// Use of this source code is subject to the terms of the Microsoft shared
// source or premium shared source license agreement under which you licensed
// this source code. If you did not accept the terms of the license agreement,
// you are not authorized to use this source code. For the terms of the license,
// please see the license agreement between you and Microsoft or, if applicable,
// see the SOURCE.RTF on your install media or the root of your tools installation.
// THE SOURCE CODE IS PROVIDED "AS IS", WITH NO WARRANTIES.
//

#include <algorithm>
#include "av_upnp.h"

using namespace av_upnp;
using namespace av_upnp::details;

/////////////////////////////////////////////////////////////////////////////
// wstring_buffer

wstring_buffer::wstring_buffer(unsigned int nSizeCheckPeriod)
    : m_nMaxSize(0),
      m_nUsesSinceSizeCheck(0),
      m_nSizeCheckPeriod(nSizeCheckPeriod)
{
}


void wstring_buffer::ResetBuffer()
{
    ++m_nUsesSinceSizeCheck;
    const size_t strBuffer_size = strBuffer.size();

    if( m_nUsesSinceSizeCheck >= m_nSizeCheckPeriod )
    {
        /* NOTE:
         * av::wstring does not at time of this code's writing allow shrinking.
         * If this ability is added, here strBuffer should be shrunk to m_nMaxSize.
         */
        /* strBuffer.shrink_allocation(m_nMaxSize); */

        m_nMaxSize            = strBuffer_size;
        m_nUsesSinceSizeCheck = 0;
    }
    else
    {
        // Update m_nMaxSize to take into account the current buffer
        m_nMaxSize = max(m_nMaxSize, strBuffer_size);
    }

    // Ready the buffer for usage again
    // NOTE: assumes resize does not affect the amount of memory strBuffer has allocated internally
    strBuffer.resize(0);
}