atom_sdp.cpp

AAC编解码源码

/*
 * 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 MPEG4IP.
 * 
 * The Initial Developer of the Original Code is Cisco Systems Inc.
 * Portions created by Cisco Systems Inc. are
 * Copyright (C) Cisco Systems Inc. 2001.  All Rights Reserved.
 * 
 * Contributor(s): 
 *		Dave Mackie		[e-mail]
 */

#include "mp4common.h"

MP4SdpAtom::MP4SdpAtom() : MP4Atom("sdp ") 
{
	AddProperty(
		new MP4StringProperty("sdpText"));
}

void MP4SdpAtom::Read() 
{
	// read sdp string, length is implicit in size of atom 
	u_int64_t size = GetEnd() - m_pFile->GetPosition();
	char* data = (char*)MP4Malloc(size + 1);
	m_pFile->ReadBytes((u_int8_t*)data, size);
	data[size] = '\0';
	((MP4StringProperty*)m_pProperties[0])->SetValue(data);
	MP4Free(data);
}

void MP4SdpAtom::Write()
{
	// since length of string is implicit in size of atom
	// we need to handle this specially, and not write the terminating \0
	MP4StringProperty* pSdp = (MP4StringProperty*)m_pProperties[0];
	const char* sdpText = pSdp->GetValue();
	if (sdpText) {
		pSdp->SetFixedLength(strlen(sdpText));
	}
	MP4Atom::Write();
	pSdp->SetFixedLength(0);
}