/*
 *	The Unix Channel
 *
 *	by Michel Beaudouin-Lafon
 *
 *	Copyright 1990-1993
 *	Laboratoire de Recherche en Informatique (LRI)
 *
 *	Channel sets, or multiplexers
 *
 *	$Id$
 *	$CurLog$
 */

#ifndef UchMultiplexer_H_
#define UchMultiplexer_H_

#include "dnn/Loop.h"
#include "Channel.h"
#include <sys/types.h>
#include "ccu/Timer.h"

extern	char*	StrReprBuf;

//	This class defines channel sets for multiplexing i/o
//	Because of the coercion defined for FILDES -> int,
//	most arguments of type ints can be FILDES, UchChannel, ...
//	An array of pointers to channels is kept in the object;
//	The masks for reading/writing are kept consistent with the IOMode of
//	the channels, as long as it is not changed by a direct access to the channel
//	operator[] returns a pointer and cannot be used as an lhs of an assignment.
//

//     WARNING: when the Multiplexer is deleted, the Channels it still
//     have in its channel set are not Removed; instead UchChannel::Removed
//     is called 

typedef DnnMpxHook UchMpxHook;

class UchBaseMultiplexer : public DnnBaseMultiplexer {
friend	class	UchBaseTimeOut;
friend	class	UchBaseSignalHandler;
friend	class	UchChannel;
friend	MPX_RES	UchLoop ();

protected:
	UchChannel**	Channels;
	CcuTimerSet	Timers;
	short		ReadCount;
	short		WriteCount;
	short		SelectCount;
	bool		Looping;
	bool	SigFired;
	UchBaseSignalHandler**	Handlers;
	int*	NbSignals;

	bool	Add (UchChannel*);
	bool	Remove (int);
	void	HandleSignal (UchBaseSignalHandler&);
	void	HandleDeferredSignals ();
inline	CcuTimerSet*	GetTimerSet ()	{ return &Timers; }

virtual	void	SetMasks (int, IOMODE);
virtual	void	SetTimeOut (Millisecond) = 0;
virtual	void	SuppressTimeOut () = 0;
virtual	void	AddSignalHook ();

public:
		UchBaseMultiplexer ();
		~UchBaseMultiplexer ();
	
	UchChannel*	operator [] (int);

	void	RemoveAll ();
	void	SetMode (int, IOMODE);
	MPX_RES	Run ();

	void	Abort ();
	void	Close ();
};


class UchMultiplexer : public UchBaseMultiplexer {
protected:
	fd_set	ReadMask;
	fd_set	WriteMask;
	fd_set	SelectMask;
	CcuList	Hooks;
	CcuList	FinalHooks;
	bool	Looping;
	Millisecond	TimeOut;

	void	SetMasks (int, IOMODE);
	void	SetTimeOut (Millisecond);
	void	SuppressTimeOut ();
	MPX_RES	Loop ();
	void	ExecHooks (bool = false);


public:
		UchMultiplexer ();
		~UchMultiplexer ();
	
	MPX_RES	LoopScan (bool nointr = true);
	int	Scan (bool nointr = true, bool poll = false);
	void	Stop ();
	char*	StrRepr (char* = StrReprBuf);
	void	AddHook (DnnMpxHook*, bool = false);
	void	RemoveHook (DnnMpxHook*, bool = false);
	void	AddFinalHook (DnnMpxHook*);
	void	RemoveFinalHook (DnnMpxHook*);
};

extern UchBaseMultiplexer* UchMpx;
extern void UchOpen (UchBaseMultiplexer* = 0);
extern MPX_RES UchLoop ();
extern void UchStop ();

#endif /* UchMultiplexer_H_ */