text: /* Copyright (c) 1985 Ceriel J.H. Jacobs */
  
  /*
   * Terminal handling routines, mostly initializing.
   */
  
  # ifndef lint
  static char rcsid[] = "$Header$";
  # endif
  
  # define _TERM_
  
  #include "in_all.h"
  #include "term.h"
  #include "machine.h"
  #include "output.h"
  #include "display.h"
  #include "options.h"
  #include "getline.h"
  #include "keys.h"
  #include "main.h"
  
  #ifdef TIOCGWINSZ
  static struct winsize w;
  #endif
  
  char	*strcpy(),
  	*strcat(),
  	*tgoto(),
  	*tgetstr(),
  	*getenv();
  
  static char	tcbuf1[1024];	/* Holds terminal capability strings */
  static char *	ptc;		/* Pointer in it */
  static char	tcbuf[1024];	/* Another termcap buffer */
  short	ospeed;		/* Needed for tputs() */
  char	PC;		/* Needed for tputs() */
  char *	UP;		/* Needed for tgoto() */
  static char	*ll;
  
  struct linelist _X[100];	/* 100 is enough ? */
  
  # if USG_TTY
  static struct termio _tty,_svtty;
  # elif POSIX_TTY
  static struct termios _tty, _svtty;
  # else
  # ifdef TIOCSPGRP
  static int proc_id, saved_pgrpid;
  # endif
  static struct sgttyb _tty,_svtty;
  # ifdef TIOCGETC
  static struct tchars _ttyc, _svttyc;
  # endif
  # ifdef TIOCGLTC
  static int line_discipline;
  static struct ltchars _lttyc, _svlttyc;
  # endif
  # endif
  
  static VOID
  handle(c) char *c; {	/* if character *c is used, set it to undefined */
  
  	if (isused(*c)) *c = 0377;
  }
  
  /*
   * Set terminal in cbreak mode.
   * Also check if tabs need expanding.
   */
  
  VOID
  inittty() {
  # if USG_TTY
  	register struct termio *p = &_tty;
  
  	ioctl(0,TCGETA,(char *) p);
  	_svtty = *p;
  	if (p->c_oflag & TAB3) {
  		/*
  		 * We do tab expansion ourselves
  		 */
  		expandtabs = 1;
  	}
  	p->c_oflag &= ~(TAB3|OCRNL|ONLRET|ONLCR);
  	p->c_oflag |= (/*ONOCR|*/OPOST);	/* ONOCR does not seem to work
  						   very well in combination with
  						   ~ONLCR
  						*/
  	p->c_lflag &= ~(ECHO|ECHOE|ECHOK|ECHONL|ICANON);
  	if (isused('S'&037) || isused('Q'&037)) p->c_iflag &= ~IXON;
  	handle(&(p->c_cc[0]));	/* INTR and QUIT (mnemonics not defined ??) */
  	handle(&(p->c_cc[1]));
  	erasech = p->c_cc[VERASE];
  	killch = p->c_cc[VKILL];
  	p->c_cc[VMIN] = 1;	/* Just wait for one character */
  	p->c_cc[VTIME] = 0;
  	ospeed = p->c_cflag & CBAUD;
  	ioctl(0,TCSETAW,(char *) p);
  #elif POSIX_TTY
  	register struct termios *p = &_tty;
  
  	tcgetattr(0, p);
  	_svtty = *p;
  #ifdef _MINIX	/* Should be XTABS */
  	if (p->c_oflag & XTABS) {
  		/*
  		 * We do tab expansion ourselves
  		 */
  		expandtabs = 1;
  	}
  	p->c_oflag &= (OPOST|XTABS);
  #else
  	p->c_oflag &= ~OPOST;
  #endif
  	p->c_lflag &= ~(ECHO|ECHOE|ECHOK|ECHONL|ICANON);
  	if (isused('S'&037) || isused('Q'&037)) p->c_iflag &= ~IXON;
  	handle(&(p->c_cc[VINTR]));	
  	handle(&(p->c_cc[VQUIT]));
  	erasech = p->c_cc[VERASE];
  	killch = p->c_cc[VKILL];
  	p->c_cc[VMIN] = 1;	/* Just wait for one character */
  	p->c_cc[VTIME] = 0;
  	ospeed = cfgetospeed(p);
  	tcsetattr(0, TCSANOW, p);
  # else
  	register struct sgttyb *p = &_tty;
  
  # ifdef TIOCSPGRP
  	/*
  	 * If we can, we put yap in another process group, and the terminal
  	 * with it. This is done, so that interrupts given by the user
  	 * will only affect yap and not it's children (processes writing
  	 * on a pipe to yap)
  	 */
  	if (ioctl(0, TIOCSPGRP, (char *) &proc_id) != -1) {
  		setpgrp(0, proc_id);
  	}
  # endif
  	ioctl(0,TIOCGETP,(char *) p);
  	_svtty = *p;
  	erasech = p->sg_erase;
  	killch = p->sg_kill;
  	ospeed = p->sg_ospeed;
  	if (p->sg_flags & XTABS) {
  		/*
  		 * We do tab expansion ourselves
  		 */
  		expandtabs = 1;
  	}
  	p->sg_flags |= (CBREAK);
  	p->sg_flags &= ~(ECHO|XTABS|RAW|LCASE|CRMOD);
  #ifdef TIOCSETN
  	ioctl(0, TIOCSETN, (char *) p);
  #else
  	ioctl(0,TIOCSETP,(char *) p);
  #endif
  /* Bloody Sun ... */
  #undef t_startc
  #undef t_stopc
  #undef t_intrc
  #undef t_quitc
  #undef t_suspc
  #undef t_dsuspc
  #undef t_flushc
  #undef t_lnextc
  # ifdef TIOCGETC
  	{   register struct tchars *q = &_ttyc;
  
  		ioctl(0,TIOCGETC,(char *) q);
  		_svttyc = *q;
  		handle(&(q->t_intrc));
  		handle(&(q->t_quitc));
  		if (isused(q->t_startc) || isused(q->t_stopc)) {
  			q->t_startc = q->t_stopc = 0377;
  		}
  		ioctl(0,TIOCSETC, (char *) q);
  	}
  # endif
  # ifdef TIOCGLTC
  	{   register struct ltchars *q = &_lttyc;
  
  		ioctl(0,TIOCGETD,(char *) &line_discipline);
  		if (line_discipline == NTTYDISC) {
  			ioctl(0, TIOCGLTC,(char *) q);
  			_svlttyc = *q;
  			handle(&(q->t_suspc));
  			handle(&(q->t_dsuspc));
  			q->t_flushc = q->t_lnextc = 0377;
  			ioctl(0,TIOCSLTC, (char *) q);
  		}
  	}
  # endif
  # endif
  }
  
  /*
   * Reset the terminal to its original state
   */
  
  VOID
  resettty() {
  
  # if USG_TTY
  	ioctl(0,TCSETAW,(char *) &_svtty);
  # elif POSIX_TTY
  	tcsetattr(0, TCSANOW, &_svtty);
  # else
  # ifdef TIOCSPGRP
  	ioctl(0, TIOCSPGRP, (char *) &saved_pgrpid);
  	setpgrp(0, saved_pgrpid);
  # endif
  	ioctl(0,TIOCSETP,(char *) &_svtty);
  # ifdef TIOCGETC
  	ioctl(0,TIOCSETC, (char *) &_svttyc);
  # endif
  # ifdef TIOCGLTC
  	if (line_discipline == NTTYDISC) ioctl(0,TIOCSLTC, (char *) &_svlttyc);
  # endif
  # endif
  	putline(TE);
  	flush();
  }
  
  /*
   * Get terminal capability "cap".
   * If not present, return an empty string.
   */
  
  STATIC char *
  getcap(cap) char *cap; {
  	register char *s;
  
  	s = tgetstr(cap, &ptc);
  	if (!s) return "";
  	return s;
  }
  
  /*
   * Initialize some terminal-dependent stuff.
   */
  
  VOID
  ini_terminal() {
  
  	register char * s;
  	register struct linelist *lp, *lp1;
  	register i;
  	register UG, SG;
  	char tempbuf[20];
  	char *mb, *mh, *mr;	/* attributes */
  
  	initkeys();
  #if !_MINIX
  # ifdef TIOCSPGRP
  	proc_id = getpid();
  	ioctl(0,TIOCGPGRP, (char *) &saved_pgrpid);
  # endif
  #endif
  	inittty();
  	stupid = 1;
  	ptc = tcbuf1;
  	BC = "\b";
  	TA = "\t";
  	if (!(s = getenv("TERM"))) s = "dumb";
  	if (tgetent(tcbuf, s) <= 0) {
  		panic("No termcap entry");
  	}
  	stupid = 0;
  	hardcopy = tgetflag("hc");	/* Hard copy terminal?*/
  	PC = *(getcap("pc"));
  	if (*(s = getcap("bc"))) {
  		/*
  		 * Backspace if not ^H
  		 */
  		BC = s;
  	}
  	UP = getcap("up");		/* move up a line */
  	CE = getcap("ce");		/* clear to end of line */
  	CL = getcap("cl");		/* clear screen */
  	if (!*CL) cflag = 1;
  	TI = getcap("ti");		/* Initialization for CM */
  	TE = getcap("te");		/* end for CM */
  	CM = getcap("cm");		/* cursor addressing */
  	SR = getcap("sr");		/* scroll reverse */
  	AL = getcap("al");		/* Insert line */
  	SO = getcap("so");		/* standout */
  	SE = getcap("se");		/* standend */
  	SG = tgetnum("sg");		/* blanks left by SO, SE */
  	if (SG < 0) SG = 0;
  	US = getcap("us");		/* underline */
  	UE = getcap("ue");		/* end underline */
  	UG = tgetnum("ug");		/* blanks left by US, UE */
  	if (UG < 0) UG = 0;
  	UC = getcap("uc");		/* underline a character */
  	mb = getcap("mb");		/* blinking attribute */
  	MD = getcap("md");		/* bold attribute */
  	ME = getcap("me");		/* turn off attributes */
  	mh = getcap("mh");		/* half bright attribute */
  	mr = getcap("mr");		/* reversed video attribute */
  	if (!nflag) {
  		/*
  		 * Recognize special strings
  		 */
  		(VOID) addstring(SO,SG,&sppat);
  		(VOID) addstring(SE,SG,&sppat);
  		(VOID) addstring(US,UG,&sppat);
  		(VOID) addstring(UE,UG,&sppat);
  		(VOID) addstring(mb,0,&sppat);
  		(VOID) addstring(MD,0,&sppat);
  		(VOID) addstring(ME,0,&sppat);
  		(VOID) addstring(mh,0,&sppat);
  		(VOID) addstring(mr,0,&sppat);
  		if (*UC) {
  			(VOID) strcpy(tempbuf,BC);
  			(VOID) strcat(tempbuf,UC);
  			(VOID) addstring(tempbuf,0,&sppat);
  		}
  	}
  	if (UG > 0 || uflag) {
  		US = "";
  		UE = "";
  	}
  	if (*US || uflag) UC = "";
  	COLS = tgetnum("co");		/* columns on page */
  	i = tgetnum("li");		/* Lines on page */
  	AM = tgetflag("am");		/* terminal wraps automatically? */
  	XN = tgetflag("xn");		/* and then ignores next newline? */
  	DB = tgetflag("db");		/* terminal retains lines below */
  	if (!*(s = getcap("ho")) && *CM) {
  		s = tgoto(CM,0,0);	/* Another way of getting home */
  	}
  	if ((!*CE && !*AL) || !*s || hardcopy) {
  		cflag = stupid = 1;
  	}
  	(VOID) strcpy(HO,s);
  	if (*(s = getcap("ta"))) {
  		/*
  		 * Tab (other than ^I or padding)
  		 */
  		TA = s;
  	}
         if (!*(ll = getcap("ll")) && *CM && i > 0) {
  		/*
  		 * Lower left hand corner
  		 */
                 (VOID) strcpy(BO, tgoto(CM,0,i-1));
  	}
         else    (VOID) strcpy(BO, ll);
  	if (COLS <= 0 || COLS > 256) {
  		if ((unsigned) COLS >= 65409) {
  			/* SUN bug */
  			COLS &= 0xffff;
  			COLS -= (65409 - 128);
  		}
  		if (COLS <= 0 || COLS > 256) COLS = 80;
  	}
  	if (i <= 0) {
  		i = 24;
  		cflag = stupid = 1;
  	}
  	LINES = i;
  	maxpagesize = i - 1;
  	scrollsize = maxpagesize / 2;
  	if (scrollsize <= 0) scrollsize = 1;
  	if (!pagesize || pagesize >= i) {
  		pagesize = maxpagesize;
  	}
  
  	/*
  	 * The next part does not really belong here, but there it is ...
  	 * Initialize a circular list for the screenlines.
  	 */
  
         scr_info.tail = lp = _X;
         lp1 = lp + (100 - 1);
  	for (; lp <= lp1; lp++) {
  		/*
  		 * Circular doubly linked list
  		 */
  		lp->next = lp + 1;
  		lp->prev = lp - 1;
  	}
         lp1->next = scr_info.tail;
  	lp1->next->prev = lp1;
  	if (stupid) {
  		(VOID) strcpy(BO,"\r\n");
  	}
  	putline(TI);
  	window();
  }
  
  /*
   * Place cursor at start of line n.
   */
  
  VOID
  mgoto(n) register n; {
  
  	if (n == 0) home();
  	else if (n == maxpagesize && *BO) bottom();
  	else if (*CM) {
  		/*
  		 * Cursor addressing
  		 */
  		tputs(tgoto(CM,0,n),1,fputch);
  	}
  	else if (*BO && *UP && n >= (maxpagesize >> 1)) {
  		/*
  		 * Bottom and then up
  		 */
  		bottom();
  		while (n++ < maxpagesize) putline(UP);
  	}
  	else {	/* Home, and then down */
  		home();
  		while (n--) putline("\r\n");
  	}
  }
  
  /*
   * Clear bottom line
   */
  
  VOID
  clrbline() {
  
  	if (stupid) {
  		putline("\r\n");
  		return;
  	}
  	bottom();
  	if (*CE) {
  		/*
  		 * We can clear to end of line
  		 */
  		clrtoeol();
  		return;
  	}
  # ifdef VT100_PATCH
  	insert_line(maxpagesize);
  # else
  	insert_line();
  # endif
  }
  
  # ifdef VT100_PATCH
  ins_line(l) {
  	tputs(tgoto(AL, l, 0), maxpagesize - l, fputch);
  }
  # endif
  
  VOID
  home() {
  
  	tputs(HO,1,fputch);
  }
  
  VOID
  bottom() {
  
  	tputs(BO,1,fputch);
  	if (!*BO) mgoto(maxpagesize);
  }
  
  int
  window()
  {
  #ifdef TIOCGWINSZ
          if (ioctl(1, TIOCGWINSZ, &w) < 0) return 0;
  
          if (w.ws_col == 0) w.ws_col = COLS;
          if (w.ws_row == 0) w.ws_row = LINES;
          if (w.ws_col != COLS || w.ws_row != LINES) {
  		COLS = w.ws_col;
  		LINES = w.ws_row;
  		maxpagesize = LINES - 1;
  		pagesize = maxpagesize;
  		if (! *ll) (VOID) strcpy(BO, tgoto(CM,0,maxpagesize));
  		scr_info.currentpos = 0;
  		scrollsize = maxpagesize / 2; 
  		if (scrollsize <= 0) scrollsize = 1;
  		return 1;
          }
  #endif
          return 0;
  }
  