/*
 * Copyright (c) 1993-1995 The Regents of the University of California.
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 * 	This product includes software developed by the Network Research
 * 	Group at Lawrence Berkeley National Laboratory.
 * 4. Neither the name of the University nor of the Laboratory may be used
 *    to endorse or promote products derived from this software without
 *    specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * @(#) $Header: transmitter.h,v 1.6 96/03/16 13:14:00 van Exp $ (LBL)
 */

#ifndef vic_transmitter_h
#define vic_transmitter_h

#ifdef WIN32
#include <winsock.h>
#else
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/uio.h>
#endif
#include "Tcl.h"
#include "timer.h"
#include "rtp.h"
#include "inet.h"

/*
 * The base object for performing the outbound path of
 * the application level protocol.
 */
class Transmitter : public TclObject, public Timer {
    public:
	Transmitter();
	virtual void timeout();

	struct buffer {
		struct buffer* next;
		/*
		 * make buffer twice as big as necessary so we can
		 * run off end while doing in-place encoding.
		 */
		u_char data[2 * RTP_MTU];
	};
	struct pktbuf {
		struct pktbuf* next;
		iovec iov[2];
		u_char hdr[MAXHDR];
		buffer* buf;
	};
	static void dump(int fd);
	static inline void seqno(u_int16_t s) { seqno_ = s; }
	inline void bps(int kbps) { kbps = kbps_; }
	inline int mtu() const { return (mtu_); }
	void flush();
	void send(pktbuf*);
	/*
	 * Buffer allocation hooks.
	 */
	pktbuf* alloch(u_int32_t, int fmt);
	void release(pktbuf*);
	pktbuf* alloc(u_int32_t, int fmt);
    protected:
	void update(int nbytes);
	void dump(int fd, iovec*, int iovel) const;
	void loopback(pktbuf*);
	void output(pktbuf* pb);
	virtual void transmit(pktbuf* pb) = 0;
	double gettimeofday() const;
	double txtime(pktbuf* pb);

	int mtu_;		/* mtu of wire (as seen by application) */
	msghdr mh_;

	int nf_;		/* number of frames sent */
	int nb_;		/* number of bytes sent */
	int np_;		/* number of packets sent */
	
	int kbps_;		/* bit-rate for interpkt spacing */
	double nextpkttime_;

	/* packet transmission queue */
	int busy_;
	pktbuf* head_;
	pktbuf* tail_;

	int loopback_;		/* true to loopback data packets */
	static int dumpfd_;	/* fd to dump packet stream to */
	static u_int16_t seqno_;
    private:
	static pktbuf* freehdrs_;
	static buffer* freebufs_;
	static int nbufs_;
	static int nhdrs_;
};

#endif
