#include "../h/param.h"#include "../h/systm.h"#include "../h/dir.h"#include "../h/user.h"#include "../h/reg.h"#include "../h/proc.h"#include "../h/tty.h"#include "../h/inode.h"#define	KERNEL	1#include "../h/mx.h"#include "../h/file.h"#include "../h/conf.h"/* * Multiplexor:   clist version * * installation: *	requires a line in cdevsw - *		mxopen, mxclose, mxread, mxwrite, mxioctl, 0, * *	also requires a line in linesw - *		mxopen, mxclose, mcread, mcwrite, mxioctl, nulldev, nulldev, * *	The linesw entry for mpx should be the last one in the table. *	'nldisp' (number of line disciplines) should not include the *	mpx line.  This is to prevent mpx from being enabled by an ioctl. *	mxtty.c must be loaded instead of tty.c so that certain *	sleeps will not be done if a typewriter is connected to *	a channel and so that sdata will be called from ttyinput. *	 */struct	chan	chans[NCHANS];struct	schan	schans[NPORTS];struct	group	*groups[NGROUPS];int	mpxline;struct chan *xcp();dev_t	mpxdev	= -1;char	mcdebugs[NDEBUGS];/* * Allocate a channel, set c_index to index. */struct	chan *challoc(index, isport){register s;	s = spl6();	if (isport) {		register struct schan *cp, *lastcp;		cp = schans;		lastcp = &schans[NPORTS];		for (; cp < lastcp; cp++)			if (cp->c_group==NULL) {				cp->c_index = index;				cp->c_pgrp = 0;				cp->c_flags = 0;				splx(s);				return((struct chan *)cp);			}		goto out;	} else {		register struct chan *cp, *lastcp;		cp = chans;		lastcp = &chans[NCHANS];		for(; cp < lastcp; cp++) 			if(cp->c_group==NULL) {				cp->c_index = index;				cp->c_pgrp = 0;				cp->c_flags = 0;				splx(s);				return(cp);			}	}out:	splx(s);	return(NULL);}/* * Allocate a group table cell. */gpalloc(){register i,s;	s = spl6();	for(i = NGROUPS-1; i>=0; i--)		if (groups[i]==NULL) {			groups[i]++;			break;		}	splx(s);	return(i);}/* * Add a channel to the group in * inode ip. */struct chan *addch(ip, isport)struct inode *ip;{register struct chan *cp;register struct group *gp;register i;	plock(ip);	gp = &ip->i_un.i_group;	for(i=0;i<NINDEX;i++) {		cp = (struct chan *)gp->g_chans[i];		if (cp == NULL) {			if ((cp=challoc(i, isport)) != NULL) {				gp->g_chans[i] = cp;				cp->c_group = gp;			}			break;		}		cp = NULL;	}	prele(ip);	return(cp);}/* * mpxchan system call */mpxchan(){struct	inode *ip, *gip;register int i;extern	mxopen(), mcread();extern	sdata(), scontrol();dev_t	dev;struct	tty *tp;struct	file *fp, *chfp, *gfp;struct	chan *cp;struct	group *gp, *ngp;struct	a {	int	cmd;	int	*argvec;} *uap;struct mx_args vec;	/*	 * common setup code.	 */	uap = (struct a *)u.u_ap;	copyin((caddr_t)uap->argvec, (caddr_t)&vec, sizeof vec);	gp = NULL;	switch(uap->cmd) {	case NPGRP:		if (vec.m_arg[1] < 0)			goto sw;	case CHAN:	case JOIN:	case EXTR:	case ATTACH:	case DETACH:	case CSIG:		gfp = getf(vec.m_arg[1]);		if (gfp==NULL)			goto bad;		gip = gfp->f_inode;		gp = &gip->i_un.i_group;		if (gp->g_inode != gip)			goto bad;	}sw:	switch(uap->cmd) {	/*	 * creat an mpx file.	 */	case MPX:	case MPXN:		if (mpxdev < 0) {			for(i=0; linesw[i].l_open; i++) 				if (linesw[i].l_read == mcread) {					mpxline = i;					goto found1;				}			goto bad;		found1:			for(i=0; cdevsw[i].d_open; i++) {				if (cdevsw[i].d_open == mxopen)					goto found2;			}		bad:			u.u_error = ENXIO;			return;		found2:			mpxdev = (dev_t)(i<<8);		}		if (uap->cmd==MPXN) {			if ((ip=ialloc(rootdev))==NULL)				goto bad;			ip->i_mode = 0666+IFCHR;			goto merge;		}		u.u_dirp = vec.m_name;		ip = namei(uchar,1);		if (ip != NULL) {			u.u_error = EEXIST;			iput(ip);			return;		}		if (u.u_error)			return;		ip = maknode((vec.m_arg[0]&0777)+IFCHR);		if (ip == NULL)			return;	merge:		if ((i = gpalloc()) < 0) {			iput(ip);			goto bad;		}		ip->i_un.i_rdev = (daddr_t)(mpxdev+i);		gp = &ip->i_un.i_group;		groups[i] = gp;		gp->g_inode = ip;		gp->g_state = COPEN;		gp->g_group = NULL;		gp->g_index = 0;		gp->g_rotmask = 1;		gp->g_rot = 0;		gp->g_datq = 0;		open1(ip,FREAD+FWRITE,2);		if (u.u_error) {			groups[i] = NULL;			iput(ip);			goto bad;		}		ip->i_mode = (ip->i_mode & ~IFMT) | IFMPC;		ip->i_count++;		ip->i_flag |= IACC|IUPD|ICHG;		fp = u.u_ofile[u.u_r.r_val1];		fp->f_flag |= FMP;		fp->f_un.f_chan = NULL;		gp->g_file = fp;		for(i=0;i<NINDEX;)			gp->g_chans[i++] = NULL;		return;	/*	 * join file descriptor (arg 0) to group (arg 1)	 * return channel number	 */	case JOIN:		if ((fp=getf(vec.m_arg[0]))==NULL)			goto bad;		ip = fp->f_inode;		i = ip->i_mode & IFMT;		if (i == IFMPC) {			if ((fp->f_flag&FMP) != FMP) {				goto bad;			}			ngp = &ip->i_un.i_group;			mlink (ngp, gp);			fp->f_count++;			return;		}		if (i != IFCHR) 			goto bad;		dev = (dev_t)ip->i_un.i_rdev;		tp = cdevsw[major(dev)].d_ttys;		if (tp==NULL)			goto bad;		tp = &tp[minor(dev)];		if (tp->t_chan)			goto bad;		if ((cp=addch(gip, 1))==NULL)			goto bad;		tp->t_chan = cp;		cp->c_fy = fp;		fp->f_count++;		cp->c_ttyp = tp;		cp->c_line = tp->t_line;		cp->c_flags = XGRP+PORT;		u.u_r.r_val1 = cpx(cp);		return;	/*	 * attach channel (arg 0) to group (arg 1)	 */	case ATTACH:		cp = xcp(gp, vec.m_arg[0]);		if (cp==NULL)			goto bad;		u.u_r.r_val1 = cpx(cp);		wakeup((caddr_t)cp);		return;	case DETACH:		cp = xcp(gp, vec.m_arg[0]);		if (cp==NULL)			goto bad;		detach(cp);		return;	/*	 * extract channel (arg 0) from group (arg 1).	 */	case EXTR:		cp = xcp(gp, vec.m_arg[0]);		if (cp==NULL) {			goto bad;		}		if (cp->c_flags & ISGRP) {			mxfalloc(((struct group *)cp)->g_file);			return;		}		if ((fp = cp->c_fy) != NULL) {			mxfalloc(fp);			return;		}		if ((fp = falloc()) == NULL) {			return;		}		fp->f_inode = gip;		gip->i_count++;		fp->f_un.f_chan = cp;		fp->f_flag = (vec.m_arg[2]) ?				(FREAD|FWRITE|FMPY) : (FREAD|FWRITE|FMPX);		cp->c_fy = fp;		return;	/*	 * make new chan on group (arg 1)	 */	case CHAN:		if ((cp=addch(gip, 0))==NULL)			goto bad;		cp->c_flags = XGRP;		cp->c_fy = NULL;		cp->c_ttyp = cp->c_ottyp = (struct tty *)cp;		cp->c_line = cp->c_oline = mpxline;		u.u_r.r_val1 = cpx(cp);		return;	/*	 * connect fd (arg 0) to channel fd (arg 1)	 * (arg 2 <  0) => fd to chan only	 * (arg 2 >  0) => chan to fd only	 * (arg 2 == 0) => both directions	 */	case CONNECT:		if ((fp=getf(vec.m_arg[0]))==NULL)			goto bad;		if ((chfp=getf(vec.m_arg[1]))==NULL)			goto bad;		ip = fp->f_inode;		i = ip->i_mode&IFMT;		if (i!=IFCHR)			goto bad;		dev = (dev_t)ip->i_un.i_rdev;		tp = cdevsw[major(dev)].d_ttys;		if (tp==NULL)			goto bad;		tp = &tp[minor(dev)];		if (!(chfp->f_flag&FMPY)) {			goto bad;		}		cp = chfp->f_un.f_chan;		if (cp==NULL || cp->c_flags&PORT) {			goto bad;		}		i = vec.m_arg[2];		if (i>=0) {			cp->c_ottyp = tp;			cp->c_oline = tp->t_line;		}		if (i<=0)  {			tp->t_chan = cp;			cp->c_ttyp = tp;			cp->c_line = tp->t_line;		}		return;	case NPGRP: {		register struct proc *pp;		if (gp != NULL) {			cp = xcp(gp, vec.m_arg[0]);			if (cp==NULL)				goto bad;		}		pp = u.u_procp;		pp->p_pgrp = pp->p_pid;		if (vec.m_arg[2])			pp->p_pgrp = vec.m_arg[2];		if (gp != NULL)			cp->c_pgrp = pp->p_pgrp;		return;	}	case CSIG:		cp = xcp(gp, vec.m_arg[0]);		if (cp==NULL)			goto bad;		signal(cp->c_pgrp, vec.m_arg[2]);		return;	case DEBUG:		i = vec.m_arg[0];		if (i<0 || i>NDEBUGS)			return;		mcdebugs[i] = vec.m_arg[1];		if (i==ALL)			for(i=0;i<NDEBUGS;i++)				mcdebugs[i] = vec.m_arg[1];		return;	default:		goto bad;	}}detach(cp)register struct chan *cp;{	register struct group *gp;	register int i;	if (cp->c_flags&ISGRP) {		gp = (struct group *)cp;		closef(gp->g_file);		i = ((struct group *)cp)->g_index;		gp->g_chans[i] = NULL;		return;	} else if (cp->c_flags&PORT && cp->c_ttyp != NULL) {		closef(cp->c_fy);		chdrain(cp);		chfree(cp);		return;	}	if (cp->c_fy && (cp->c_flags&WCLOSE)==0) {		cp->c_flags |= WCLOSE;		chwake(cp);	} else {		chdrain(cp);		chfree(cp);	}}mxfalloc(fp)register struct file *fp;{register i;	if (fp==NULL) {		u.u_error = ENXIO;		return;	}	i = ufalloc();	if (i < 0)		return;	u.u_ofile[i] = fp;	fp->f_count++;	u.u_r.r_val1 = i;	return;}mlink(sub,master)struct group *sub, *master;{register i;	for(i=0;i<NINDEX;i++) {		if (master->g_chans[i] != NULL)			continue;		master->g_chans[i] = (struct chan *)sub;		sub->g_group = master;		sub->g_index = i;		u.u_r.r_val1 = i;		return;	}	u.u_error = ENXIO;	return;}