www.pudn.com > simplec++codeforp2p.rar > atom.h

// ------------------------------------------------ 
// File : atom.h 
// Date: 1-mar-2004 
// Author: giles 
// 
// (c) 2002-4 peercast.org 
// ------------------------------------------------ 
// This program is free software; you can redistribute it and/or modify 
// it under the terms of the GNU General Public License as published by 
// the Free Software Foundation; either version 2 of the License, or 
// (at your option) any later version. 
 
// This program is distributed in the hope that it will be useful, 
// but WITHOUT ANY WARRANTY; without even the implied warranty of 
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
// GNU General Public License for more details. 
// ------------------------------------------------ 
 
#ifndef _ATOM_H 
#define _ATOM_H 
 
#include "stream.h" 
 
#include "id.h" 
 
// ------------------------------------------------ 
class AtomStream 
{ 
public: 
	AtomStream(Stream &s) : io(s),numChildren(0),numData(0) 
	{} 
 
	void checkData(int d) 
	{ 
		if (numData != d) 
			throw StreamException("Bad atom data"); 
	} 
 
	void writeParent(ID4 id,int nc) 
	{ 
		io.writeID4(id); 
		io.writeInt(nc|0x80000000); 
	} 
 
	void writeInt(ID4 id,int d) 
	{ 
		io.writeID4(id); 
		io.writeInt(4); 
		io.writeInt(d); 
	} 
	 
	void writeID4(ID4 id,ID4 d) 
	{ 
		io.writeID4(id); 
		io.writeInt(4); 
		io.writeID4(d); 
	} 
 
	void writeShort(ID4 id,short d) 
	{ 
		io.writeID4(id); 
		io.writeInt(2); 
		io.writeShort(d); 
	} 
 
	void writeChar(ID4 id,char d) 
	{ 
		io.writeID4(id); 
		io.writeInt(1); 
		io.writeChar(d); 
	} 
 
	void writeBytes(ID4 id,const void *p,int l) 
	{ 
		io.writeID4(id); 
		io.writeInt(l); 
		io.write(p,l); 
	} 
 
 
	int writeStream(ID4 id,Stream &in,int l) 
	{ 
		io.writeID4(id); 
		io.writeInt(l); 
		in.writeTo(io,l); 
		return (sizeof(int)*2)+l; 
 
	} 
 
	void writeString(ID4 id,const char *p) 
	{ 
		writeBytes(id,p,strlen(p)+1); 
	} 
 
	ID4	read(int &numc,int &dlen) 
	{ 
		ID4 id = io.readID4(); 
 
		unsigned int v = io.readInt(); 
		if (v & 0x80000000) 
		{ 
			numc = v&0x7fffffff; 
			dlen = 0; 
		}else 
		{ 
			numc = 0; 
			dlen = v; 
		} 
 
		numChildren = numc; 
		numData = dlen; 
 
		return id; 
	} 
 
	void skip(int c, int d) 
	{ 
		if (d) 
			io.skip(d); 
 
		for(int i=0; i dlen) 
			readBytes(s,dlen); 
		else 
		{ 
			readBytes(s,max); 
			io.skip(dlen-max); 
		} 
	} 
 
	int		writeAtoms(ID4 id, Stream &in, int cnt, int data) 
	{ 
		int total=0; 
 
		if (cnt) 
		{ 
			writeParent(id,cnt); 
			total+=sizeof(int)*2; 
 
			for(int i=0; i