xref: /original-bsd/old/more/more.c (revision 792e4f5f)
1 /*
2  * Copyright (c) 1980 Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms are permitted
6  * provided that the above copyright notice and this paragraph are
7  * duplicated in all such forms and that any documentation,
8  * advertising materials, and other materials related to such
9  * distribution and use acknowledge that the software was developed
10  * by the University of California, Berkeley.  The name of the
11  * University may not be used to endorse or promote products derived
12  * from this software without specific prior written permission.
13  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
14  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
15  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
16  */
17 
18 #ifndef lint
19 char copyright[] =
20 "@(#) Copyright (c) 1980 Regents of the University of California.\n\
21  All rights reserved.\n";
22 #endif /* not lint */
23 
24 #ifndef lint
25 static char sccsid[] = "@(#)more.c	5.21 (Berkeley) 05/11/89";
26 #endif /* not lint */
27 
28 /*
29 ** more.c - General purpose tty output filter and file perusal program
30 **
31 **	by Eric Shienbrood, UC Berkeley
32 **
33 **	modified by Geoff Peck, UCB to add underlining, single spacing
34 **	modified by John Foderaro, UCB to add -c and MORE environment variable
35 */
36 
37 #include <stdio.h>
38 #include <sys/param.h>
39 #include <ctype.h>
40 #include <signal.h>
41 #include <errno.h>
42 #include <sgtty.h>
43 #include <setjmp.h>
44 #include <sys/stat.h>
45 #include <sys/file.h>
46 #include <a.out.h>
47 #include <varargs.h>
48 #include "pathnames.h"
49 
50 #define Fopen(s,m)	(Currline = 0,file_pos=0,fopen(s,m))
51 #define Ftell(f)	file_pos
52 #define Fseek(f,off)	(file_pos=off,fseek(f,off,0))
53 #define Getc(f)		(++file_pos, getc(f))
54 #define Ungetc(c,f)	(--file_pos, ungetc(c,f))
55 
56 #define MBIT	CBREAK
57 #define stty(fd,argp)	ioctl(fd,TIOCSETN,argp)
58 
59 #define TBUFSIZ	1024
60 #define LINSIZ	256
61 #define ctrl(letter)	(letter & 077)
62 #define RUBOUT	'\177'
63 #define ESC	'\033'
64 #define QUIT	'\034'
65 
66 struct sgttyb	otty, savetty;
67 long		file_pos, file_size;
68 int		fnum, no_intty, no_tty, slow_tty;
69 int		dum_opt, dlines, onquit(), end_it(), chgwinsz();
70 int		onsusp();
71 int		nscroll = 11;	/* Number of lines scrolled by 'd' */
72 int		fold_opt = 1;	/* Fold long lines */
73 int		stop_opt = 1;	/* Stop after form feeds */
74 int		ssp_opt = 0;	/* Suppress white space */
75 int		ul_opt = 1;	/* Underline as best we can */
76 int		promptlen;
77 int		Currline;	/* Line we are currently at */
78 int		startup = 1;
79 int		firstf = 1;
80 int		notell = 1;
81 int		docrterase = 0;
82 int		docrtkill = 0;
83 int		bad_so;	/* True if overwriting does not turn off standout */
84 int		inwait, Pause, errors;
85 int		within;	/* true if we are within a file,
86 			false if we are between files */
87 int		hard, dumb, noscroll, hardtabs, clreol, eatnl;
88 int		catch_susp;	/* We should catch the SIGTSTP signal */
89 char		**fnames;	/* The list of file names */
90 int		nfiles;		/* Number of files left to process */
91 char		*shell;		/* The name of the shell to use */
92 int		shellp;		/* A previous shell command exists */
93 char		ch;
94 jmp_buf		restore;
95 char		Line[LINSIZ];	/* Line buffer */
96 int		Lpp = 24;	/* lines per page */
97 char		*Clear;		/* clear screen */
98 char		*eraseln;	/* erase line */
99 char		*Senter, *Sexit;/* enter and exit standout mode */
100 char		*ULenter, *ULexit;	/* enter and exit underline mode */
101 char		*chUL;		/* underline character */
102 char		*chBS;		/* backspace character */
103 char		*Home;		/* go to home */
104 char		*cursorm;	/* cursor movement */
105 char		cursorhome[40];	/* contains cursor movement to home */
106 char		*EodClr;	/* clear rest of screen */
107 char		*tgetstr();
108 int		Mcol = 80;	/* number of columns */
109 int		Wrap = 1;	/* set if automargins */
110 int		soglitch;	/* terminal has standout mode glitch */
111 int		ulglitch;	/* terminal has underline mode glitch */
112 int		pstate = 0;	/* current UL state */
113 long		fseek();
114 char		*getenv();
115 struct {
116     long chrctr, line;
117 } context, screen_start;
118 extern char	PC;		/* pad character */
119 extern short	ospeed;
120 
121 
122 main(argc, argv)
123 int argc;
124 char *argv[];
125 {
126     register FILE	*f;
127     register char	*s;
128     register char	*p;
129     register char	ch;
130     register int	left;
131     int			prnames = 0;
132     int			initopt = 0;
133     int			srchopt = 0;
134     int			clearit = 0;
135     int			initline;
136     char		initbuf[80];
137     FILE		*checkf();
138 
139     nfiles = argc;
140     fnames = argv;
141     initterm ();
142     nscroll = Lpp/2 - 1;
143     if (nscroll <= 0)
144 	nscroll = 1;
145     if(s = getenv("MORE")) argscan(s);
146     while (--nfiles > 0) {
147 	if ((ch = (*++fnames)[0]) == '-') {
148 	    argscan(*fnames+1);
149 	}
150 	else if (ch == '+') {
151 	    s = *fnames;
152 	    if (*++s == '/') {
153 		srchopt++;
154 		for (++s, p = initbuf; p < initbuf + 79 && *s != '\0';)
155 		    *p++ = *s++;
156 		*p = '\0';
157 	    }
158 	    else {
159 		initopt++;
160 		for (initline = 0; *s != '\0'; s++)
161 		    if (isdigit (*s))
162 			initline = initline*10 + *s -'0';
163 		--initline;
164 	    }
165 	}
166 	else break;
167     }
168     /* allow clreol only if Home and eraseln and EodClr strings are
169      *  defined, and in that case, make sure we are in noscroll mode
170      */
171     if(clreol)
172     {
173         if((Home == NULL) || (*Home == '\0') ||
174 	   (eraseln == NULL) || (*eraseln == '\0') ||
175            (EodClr == NULL) || (*EodClr == '\0') )
176 	      clreol = 0;
177 	else noscroll = 1;
178     }
179     if (dlines == 0)
180 	dlines = Lpp - (noscroll ? 1 : 2);
181     left = dlines;
182     if (nfiles > 1)
183 	prnames++;
184     if (!no_intty && nfiles == 0) {
185 	char *rindex();
186 
187 	p = rindex(argv[0], '/');
188 	fputs("usage: ",stderr);
189 	fputs(p ? p + 1 : argv[0],stderr);
190 	fputs(" [-dfln] [+linenum | +/pattern] name1 name2 ...\n",stderr);
191 	exit(1);
192     }
193     else
194 	f = stdin;
195     if (!no_tty) {
196 	signal(SIGQUIT, onquit);
197 	signal(SIGINT, end_it);
198 	signal(SIGWINCH, chgwinsz);
199 	if (signal (SIGTSTP, SIG_IGN) == SIG_DFL) {
200 	    signal(SIGTSTP, onsusp);
201 	    catch_susp++;
202 	}
203 	stty (fileno(stderr), &otty);
204     }
205     if (no_intty) {
206 	if (no_tty)
207 	    copy_file (stdin);
208 	else {
209 	    if ((ch = Getc (f)) == '\f')
210 		doclear();
211 	    else {
212 		Ungetc (ch, f);
213 		if (noscroll && (ch != EOF)) {
214 		    if (clreol)
215 			home ();
216 		    else
217 			doclear ();
218 		}
219 	    }
220 	    if (srchopt)
221 	    {
222 		search (initbuf, stdin, 1);
223 		if (noscroll)
224 		    left--;
225 	    }
226 	    else if (initopt)
227 		skiplns (initline, stdin);
228 	    screen (stdin, left);
229 	}
230 	no_intty = 0;
231 	prnames++;
232 	firstf = 0;
233     }
234 
235     while (fnum < nfiles) {
236 	if ((f = checkf (fnames[fnum], &clearit)) != NULL) {
237 	    context.line = context.chrctr = 0;
238 	    Currline = 0;
239 	    if (firstf) setjmp (restore);
240 	    if (firstf) {
241 		firstf = 0;
242 		if (srchopt)
243 		{
244 		    search (initbuf, f, 1);
245 		    if (noscroll)
246 			left--;
247 		}
248 		else if (initopt)
249 		    skiplns (initline, f);
250 	    }
251 	    else if (fnum < nfiles && !no_tty) {
252 		setjmp (restore);
253 		left = command (fnames[fnum], f);
254 	    }
255 	    if (left != 0) {
256 		if ((noscroll || clearit) && (file_size != LONG_MAX))
257 		    if (clreol)
258 			home ();
259 		    else
260 			doclear ();
261 		if (prnames) {
262 		    if (bad_so)
263 			erase (0);
264 		    if (clreol)
265 			cleareol ();
266 		    pr("::::::::::::::");
267 		    if (promptlen > 14)
268 			erase (14);
269 		    printf ("\n");
270 		    if(clreol) cleareol();
271 		    printf("%s\n", fnames[fnum]);
272 		    if(clreol) cleareol();
273 		    printf("::::::::::::::\n");
274 		    if (left > Lpp - 4)
275 			left = Lpp - 4;
276 		}
277 		if (no_tty)
278 		    copy_file (f);
279 		else {
280 		    within++;
281 		    screen(f, left);
282 		    within = 0;
283 		}
284 	    }
285 	    setjmp (restore);
286 	    fflush(stdout);
287 	    fclose(f);
288 	    screen_start.line = screen_start.chrctr = 0L;
289 	    context.line = context.chrctr = 0L;
290 	}
291 	fnum++;
292 	firstf = 0;
293     }
294     reset_tty ();
295     exit(0);
296 }
297 
298 argscan(s)
299 char *s;
300 {
301 	int seen_num = 0;
302 
303 	while (*s != '\0') {
304 		switch (*s) {
305 		  case '0': case '1': case '2':
306 		  case '3': case '4': case '5':
307 		  case '6': case '7': case '8':
308 		  case '9':
309 			if (!seen_num) {
310 				dlines = 0;
311 				seen_num = 1;
312 			}
313 			dlines = dlines*10 + *s - '0';
314 			break;
315 		  case 'd':
316 			dum_opt = 1;
317 			break;
318 		  case 'l':
319 			stop_opt = 0;
320 			break;
321 		  case 'f':
322 			fold_opt = 0;
323 			break;
324 		  case 'p':
325 			noscroll++;
326 			break;
327 		  case 'c':
328 			clreol++;
329 			break;
330 		  case 's':
331 			ssp_opt = 1;
332 			break;
333 		  case 'u':
334 			ul_opt = 0;
335 			break;
336 		}
337 		s++;
338 	}
339 }
340 
341 
342 /*
343 ** Check whether the file named by fs is an ASCII file which the user may
344 ** access.  If it is, return the opened file. Otherwise return NULL.
345 */
346 
347 FILE *
348 checkf (fs, clearfirst)
349 	register char *fs;
350 	int *clearfirst;
351 {
352 	struct stat stbuf;
353 	register FILE *f;
354 	char c;
355 
356 	if (stat (fs, &stbuf) == -1) {
357 		(void)fflush(stdout);
358 		if (clreol)
359 			cleareol ();
360 		perror(fs);
361 		return((FILE *)NULL);
362 	}
363 	if ((stbuf.st_mode & S_IFMT) == S_IFDIR) {
364 		printf("\n*** %s: directory ***\n\n", fs);
365 		return((FILE *)NULL);
366 	}
367 	if ((f = Fopen(fs, "r")) == NULL) {
368 		(void)fflush(stdout);
369 		perror(fs);
370 		return((FILE *)NULL);
371 	}
372 	if (magic(f, fs))
373 		return((FILE *)NULL);
374 	c = Getc(f);
375 	*clearfirst = c == '\f';
376 	Ungetc (c, f);
377 	if ((file_size = stbuf.st_size) == 0)
378 		file_size = LONG_MAX;
379 	return(f);
380 }
381 
382 /*
383  * magic --
384  *	check for file magic numbers.  This code would best be shared with
385  *	the file(1) program or, perhaps, more should not try and be so smart?
386  */
387 static
388 magic(f, fs)
389 	FILE *f;
390 	char *fs;
391 {
392 	struct exec ex;
393 
394 	if (fread(&ex, sizeof(ex), 1, f) == 1)
395 		switch(ex.a_magic) {
396 		case OMAGIC:
397 		case NMAGIC:
398 		case ZMAGIC:
399 		case 0405:
400 		case 0411:
401 		case 0177545:
402 			printf("\n******** %s: Not a text file ********\n\n", fs);
403 			(void)fclose(f);
404 			return(1);
405 		}
406 	(void)fseek(f, 0L, L_SET);		/* rewind() not necessary */
407 	return(0);
408 }
409 
410 /*
411 ** A real function, for the tputs routine in termlib
412 */
413 
414 putch (ch)
415 char ch;
416 {
417     putchar (ch);
418 }
419 
420 /*
421 ** Print out the contents of the file f, one screenful at a time.
422 */
423 
424 #define STOP -10
425 
426 screen (f, num_lines)
427 register FILE *f;
428 register int num_lines;
429 {
430     register int c;
431     register int nchars;
432     int length;			/* length of current line */
433     static int prev_len = 1;	/* length of previous line */
434 
435     for (;;) {
436 	while (num_lines > 0 && !Pause) {
437 	    if ((nchars = getline (f, &length)) == EOF)
438 	    {
439 		if (clreol)
440 		    clreos();
441 		return;
442 	    }
443 	    if (ssp_opt && length == 0 && prev_len == 0)
444 		continue;
445 	    prev_len = length;
446 	    if (bad_so || (Senter && *Senter == ' ') && promptlen > 0)
447 		erase (0);
448 	    /* must clear before drawing line since tabs on some terminals
449 	     * do not erase what they tab over.
450 	     */
451 	    if (clreol)
452 		cleareol ();
453 	    prbuf (Line, length);
454 	    if (nchars < promptlen)
455 		erase (nchars);	/* erase () sets promptlen to 0 */
456 	    else promptlen = 0;
457 	    /* is this needed?
458 	     * if (clreol)
459 	     *	cleareol();	/* must clear again in case we wrapped *
460 	     */
461 	    if (nchars < Mcol || !fold_opt)
462 		prbuf("\n", 1);	/* will turn off UL if necessary */
463 	    if (nchars == STOP)
464 		break;
465 	    num_lines--;
466 	}
467 	if (pstate) {
468 		tputs(ULexit, 1, putch);
469 		pstate = 0;
470 	}
471 	fflush(stdout);
472 	if ((c = Getc(f)) == EOF)
473 	{
474 	    if (clreol)
475 		clreos ();
476 	    return;
477 	}
478 
479 	if (Pause && clreol)
480 	    clreos ();
481 	Ungetc (c, f);
482 	setjmp (restore);
483 	Pause = 0; startup = 0;
484 	if ((num_lines = command (NULL, f)) == 0)
485 	    return;
486 	if (hard && promptlen > 0)
487 		erase (0);
488 	if (noscroll && num_lines >= dlines)
489 	{
490 	    if (clreol)
491 		home();
492 	    else
493 		doclear ();
494 	}
495 	screen_start.line = Currline;
496 	screen_start.chrctr = Ftell (f);
497     }
498 }
499 
500 /*
501 ** Come here if a quit signal is received
502 */
503 
504 onquit()
505 {
506     signal(SIGQUIT, SIG_IGN);
507     if (!inwait) {
508 	putchar ('\n');
509 	if (!startup) {
510 	    signal(SIGQUIT, onquit);
511 	    longjmp (restore, 1);
512 	}
513 	else
514 	    Pause++;
515     }
516     else if (!dum_opt && notell) {
517 	write (2, "[Use q or Q to quit]", 20);
518 	promptlen += 20;
519 	notell = 0;
520     }
521     signal(SIGQUIT, onquit);
522 }
523 
524 /*
525 ** Come here if a signal for a window size change is received
526 */
527 
528 chgwinsz()
529 {
530     struct winsize win;
531 
532     (void) signal(SIGWINCH, SIG_IGN);
533     if (ioctl(fileno(stdout), TIOCGWINSZ, &win) != -1) {
534 	if (win.ws_row != 0) {
535 	    Lpp = win.ws_row;
536 	    nscroll = Lpp/2 - 1;
537 	    if (nscroll <= 0)
538 		nscroll = 1;
539 	    dlines = Lpp - (noscroll ? 1 : 2);
540 	}
541 	if (win.ws_col != 0)
542 	    Mcol = win.ws_col;
543     }
544     (void) signal(SIGWINCH, chgwinsz);
545 }
546 
547 /*
548 ** Clean up terminal state and exit. Also come here if interrupt signal received
549 */
550 
551 end_it ()
552 {
553 
554     reset_tty ();
555     if (clreol) {
556 	putchar ('\r');
557 	clreos ();
558 	fflush (stdout);
559     }
560     else if (!clreol && (promptlen > 0)) {
561 	kill_line ();
562 	fflush (stdout);
563     }
564     else
565 	write (2, "\n", 1);
566     _exit(0);
567 }
568 
569 copy_file(f)
570 register FILE *f;
571 {
572     register int c;
573 
574     while ((c = getc(f)) != EOF)
575 	putchar(c);
576 }
577 
578 /* Simplified printf function */
579 
580 printf (fmt, va_alist)
581 register char *fmt;
582 va_dcl
583 {
584 	va_list ap;
585 	register char ch;
586 	register int ccount;
587 
588 	ccount = 0;
589 	va_start(ap);
590 	while (*fmt) {
591 		while ((ch = *fmt++) != '%') {
592 			if (ch == '\0')
593 				return (ccount);
594 			ccount++;
595 			putchar (ch);
596 		}
597 		switch (*fmt++) {
598 		case 'd':
599 			ccount += printd (va_arg(ap, int));
600 			break;
601 		case 's':
602 			ccount += pr (va_arg(ap, char *));
603 			break;
604 		case '%':
605 			ccount++;
606 			putchar ('%');
607 			break;
608 		case '0':
609 			return (ccount);
610 		default:
611 			break;
612 		}
613 	}
614 	va_end(ap);
615 	return (ccount);
616 
617 }
618 
619 /*
620 ** Print an integer as a string of decimal digits,
621 ** returning the length of the print representation.
622 */
623 
624 printd (n)
625 int n;
626 {
627     int a, nchars;
628 
629     if (a = n/10)
630 	nchars = 1 + printd(a);
631     else
632 	nchars = 1;
633     putchar (n % 10 + '0');
634     return (nchars);
635 }
636 
637 /* Put the print representation of an integer into a string */
638 static char *sptr;
639 
640 scanstr (n, str)
641 int n;
642 char *str;
643 {
644     sptr = str;
645     Sprintf (n);
646     *sptr = '\0';
647 }
648 
649 Sprintf (n)
650 {
651     int a;
652 
653     if (a = n/10)
654 	Sprintf (a);
655     *sptr++ = n % 10 + '0';
656 }
657 
658 static char bell = ctrl('G');
659 
660 strlen (s)
661 char *s;
662 {
663     register char *p;
664 
665     p = s;
666     while (*p++)
667 	;
668     return (p - s - 1);
669 }
670 
671 /* See whether the last component of the path name "path" is equal to the
672 ** string "string"
673 */
674 
675 tailequ (path, string)
676 char *path;
677 register char *string;
678 {
679 	register char *tail;
680 
681 	tail = path + strlen(path);
682 	while (tail >= path)
683 		if (*(--tail) == '/')
684 			break;
685 	++tail;
686 	while (*tail++ == *string++)
687 		if (*tail == '\0')
688 			return(1);
689 	return(0);
690 }
691 
692 prompt (filename)
693 char *filename;
694 {
695     if (clreol)
696 	cleareol ();
697     else if (promptlen > 0)
698 	kill_line ();
699     if (!hard) {
700 	promptlen = 8;
701 	if (Senter && Sexit) {
702 	    tputs (Senter, 1, putch);
703 	    promptlen += (2 * soglitch);
704 	}
705 	if (clreol)
706 	    cleareol ();
707 	pr("--More--");
708 	if (filename != NULL) {
709 	    promptlen += printf ("(Next file: %s)", filename);
710 	}
711 	else if (!no_intty) {
712 	    promptlen += printf ("(%d%%)", (int)((file_pos * 100) / file_size));
713 	}
714 	if (dum_opt) {
715 	    promptlen += pr("[Press space to continue, 'q' to quit.]");
716 	}
717 	if (Senter && Sexit)
718 	    tputs (Sexit, 1, putch);
719 	if (clreol)
720 	    clreos ();
721 	fflush(stdout);
722     }
723     else
724 	write (2, &bell, 1);
725     inwait++;
726 }
727 
728 /*
729 ** Get a logical line
730 */
731 
732 getline(f, length)
733 register FILE *f;
734 int *length;
735 {
736     register int	c;
737     register char	*p;
738     register int	column;
739     static int		colflg;
740 
741     p = Line;
742     column = 0;
743     c = Getc (f);
744     if (colflg && c == '\n') {
745 	Currline++;
746 	c = Getc (f);
747     }
748     while (p < &Line[LINSIZ - 1]) {
749 	if (c == EOF) {
750 	    if (p > Line) {
751 		*p = '\0';
752 		*length = p - Line;
753 		return (column);
754 	    }
755 	    *length = p - Line;
756 	    return (EOF);
757 	}
758 	if (c == '\n') {
759 	    Currline++;
760 	    break;
761 	}
762 	*p++ = c;
763 	if (c == '\t')
764 	    if (!hardtabs || column < promptlen && !hard) {
765 		if (hardtabs && eraseln && !dumb) {
766 		    column = 1 + (column | 7);
767 		    tputs (eraseln, 1, putch);
768 		    promptlen = 0;
769 		}
770 		else {
771 		    for (--p; p < &Line[LINSIZ - 1];) {
772 			*p++ = ' ';
773 			if ((++column & 7) == 0)
774 			    break;
775 		    }
776 		    if (column >= promptlen) promptlen = 0;
777 		}
778 	    }
779 	    else
780 		column = 1 + (column | 7);
781 	else if (c == '\b' && column > 0)
782 	    column--;
783 	else if (c == '\r')
784 	    column = 0;
785 	else if (c == '\f' && stop_opt) {
786 		p[-1] = '^';
787 		*p++ = 'L';
788 		column += 2;
789 		Pause++;
790 	}
791 	else if (c == EOF) {
792 	    *length = p - Line;
793 	    return (column);
794 	}
795 	else if (c >= ' ' && c != RUBOUT)
796 	    column++;
797 	if (column >= Mcol && fold_opt) break;
798 	c = Getc (f);
799     }
800     if (column >= Mcol && Mcol > 0) {
801 	if (!Wrap) {
802 	    *p++ = '\n';
803 	}
804     }
805     colflg = column == Mcol && fold_opt;
806     if (colflg && eatnl && Wrap) {
807 	*p++ = '\n'; /* simulate normal wrap */
808     }
809     *length = p - Line;
810     *p = 0;
811     return (column);
812 }
813 
814 /*
815 ** Erase the rest of the prompt, assuming we are starting at column col.
816 */
817 
818 erase (col)
819 register int col;
820 {
821 
822     if (promptlen == 0)
823 	return;
824     if (hard) {
825 	putchar ('\n');
826     }
827     else {
828 	if (col == 0)
829 	    putchar ('\r');
830 	if (!dumb && eraseln)
831 	    tputs (eraseln, 1, putch);
832 	else
833 	    for (col = promptlen - col; col > 0; col--)
834 		putchar (' ');
835     }
836     promptlen = 0;
837 }
838 
839 /*
840 ** Erase the current line entirely
841 */
842 
843 kill_line ()
844 {
845     erase (0);
846     if (!eraseln || dumb) putchar ('\r');
847 }
848 
849 /*
850  * force clear to end of line
851  */
852 cleareol()
853 {
854     tputs(eraseln, 1, putch);
855 }
856 
857 clreos()
858 {
859     tputs(EodClr, 1, putch);
860 }
861 
862 /*
863 **  Print string and return number of characters
864 */
865 
866 pr(s1)
867 char	*s1;
868 {
869     register char	*s;
870     register char	c;
871 
872     for (s = s1; c = *s++; )
873 	putchar(c);
874     return (s - s1 - 1);
875 }
876 
877 
878 /* Print a buffer of n characters */
879 
880 prbuf (s, n)
881 register char *s;
882 register int n;
883 {
884     register char c;			/* next output character */
885     register int state;			/* next output char's UL state */
886 #define wouldul(s,n)	((n) >= 2 && (((s)[0] == '_' && (s)[1] == '\b') || ((s)[1] == '\b' && (s)[2] == '_')))
887 
888     while (--n >= 0)
889 	if (!ul_opt)
890 	    putchar (*s++);
891 	else {
892 	    if (*s == ' ' && pstate == 0 && ulglitch && wouldul(s+1, n-1)) {
893 		s++;
894 		continue;
895 	    }
896 	    if (state = wouldul(s, n)) {
897 		c = (*s == '_')? s[2] : *s ;
898 		n -= 2;
899 		s += 3;
900 	    } else
901 		c = *s++;
902 	    if (state != pstate) {
903 		if (c == ' ' && state == 0 && ulglitch && wouldul(s, n-1))
904 		    state = 1;
905 		else
906 		    tputs(state ? ULenter : ULexit, 1, putch);
907 	    }
908 	    if (c != ' ' || pstate == 0 || state != 0 || ulglitch == 0)
909 	        putchar(c);
910 	    if (state && *chUL) {
911 		pr(chBS);
912 		tputs(chUL, 1, putch);
913 	    }
914 	    pstate = state;
915 	}
916 }
917 
918 /*
919 **  Clear the screen
920 */
921 
922 doclear()
923 {
924     if (Clear && !hard) {
925 	tputs(Clear, 1, putch);
926 
927 	/* Put out carriage return so that system doesn't
928 	** get confused by escape sequences when expanding tabs
929 	*/
930 	putchar ('\r');
931 	promptlen = 0;
932     }
933 }
934 
935 /*
936  * Go to home position
937  */
938 home()
939 {
940     tputs(Home,1,putch);
941 }
942 
943 static int lastcmd, lastarg, lastp;
944 static int lastcolon;
945 char shell_line[132];
946 
947 /*
948 ** Read a command and do it. A command consists of an optional integer
949 ** argument followed by the command character.  Return the number of lines
950 ** to display in the next screenful.  If there is nothing more to display
951 ** in the current file, zero is returned.
952 */
953 
954 command (filename, f)
955 char *filename;
956 register FILE *f;
957 {
958     register int nlines;
959     register int retval;
960     register char c;
961     char colonch;
962     FILE *helpf;
963     int done;
964     char comchar, cmdbuf[80], *p;
965 
966 #define ret(val) retval=val;done++;break
967 
968     done = 0;
969     if (!errors)
970 	prompt (filename);
971     else
972 	errors = 0;
973     if (MBIT == RAW && slow_tty) {
974 	otty.sg_flags |= MBIT;
975 	stty(fileno(stderr), &otty);
976     }
977     for (;;) {
978 	nlines = number (&comchar);
979 	lastp = colonch = 0;
980 	if (comchar == '.') {	/* Repeat last command */
981 		lastp++;
982 		comchar = lastcmd;
983 		nlines = lastarg;
984 		if (lastcmd == ':')
985 			colonch = lastcolon;
986 	}
987 	lastcmd = comchar;
988 	lastarg = nlines;
989 	if (comchar == otty.sg_erase) {
990 	    kill_line ();
991 	    prompt (filename);
992 	    continue;
993 	}
994 	switch (comchar) {
995 	case ':':
996 	    retval = colon (filename, colonch, nlines);
997 	    if (retval >= 0)
998 		done++;
999 	    break;
1000 	case 'b':
1001 	case ctrl('B'):
1002 	    {
1003 		register int initline;
1004 
1005 		if (no_intty) {
1006 		    write(2, &bell, 1);
1007 		    return (-1);
1008 		}
1009 
1010 		if (nlines == 0) nlines++;
1011 
1012 		putchar ('\r');
1013 		erase (0);
1014 		printf ("\n");
1015 		if (clreol)
1016 			cleareol ();
1017 		printf ("...back %d page", nlines);
1018 		if (nlines > 1)
1019 			pr ("s\n");
1020 		else
1021 			pr ("\n");
1022 
1023 		if (clreol)
1024 			cleareol ();
1025 		pr ("\n");
1026 
1027 		initline = Currline - dlines * (nlines + 1);
1028 		if (! noscroll)
1029 		    --initline;
1030 		if (initline < 0) initline = 0;
1031 		Fseek(f, 0L);
1032 		Currline = 0;	/* skiplns() will make Currline correct */
1033 		skiplns(initline, f);
1034 		if (! noscroll) {
1035 		    ret(dlines + 1);
1036 		}
1037 		else {
1038 		    ret(dlines);
1039 		}
1040 	    }
1041 	case ' ':
1042 	case 'z':
1043 	    if (nlines == 0) nlines = dlines;
1044 	    else if (comchar == 'z') dlines = nlines;
1045 	    ret (nlines);
1046 	case 'd':
1047 	case ctrl('D'):
1048 	    if (nlines != 0) nscroll = nlines;
1049 	    ret (nscroll);
1050 	case 'q':
1051 	case 'Q':
1052 	    end_it ();
1053 	case 's':
1054 	case 'f':
1055 	    if (nlines == 0) nlines++;
1056 	    if (comchar == 'f')
1057 		nlines *= dlines;
1058 	    putchar ('\r');
1059 	    erase (0);
1060 	    printf ("\n");
1061 	    if (clreol)
1062 		cleareol ();
1063 	    printf ("...skipping %d line", nlines);
1064 	    if (nlines > 1)
1065 		pr ("s\n");
1066 	    else
1067 		pr ("\n");
1068 
1069 	    if (clreol)
1070 		cleareol ();
1071 	    pr ("\n");
1072 
1073 	    while (nlines > 0) {
1074 		while ((c = Getc (f)) != '\n')
1075 		    if (c == EOF) {
1076 			retval = 0;
1077 			done++;
1078 			goto endsw;
1079 		    }
1080 		    Currline++;
1081 		    nlines--;
1082 	    }
1083 	    ret (dlines);
1084 	case '\n':
1085 	    if (nlines != 0)
1086 		dlines = nlines;
1087 	    else
1088 		nlines = 1;
1089 	    ret (nlines);
1090 	case '\f':
1091 	    if (!no_intty) {
1092 		doclear ();
1093 		Fseek (f, screen_start.chrctr);
1094 		Currline = screen_start.line;
1095 		ret (dlines);
1096 	    }
1097 	    else {
1098 		write (2, &bell, 1);
1099 		break;
1100 	    }
1101 	case '\'':
1102 	    if (!no_intty) {
1103 		kill_line ();
1104 		pr ("\n***Back***\n\n");
1105 		Fseek (f, context.chrctr);
1106 		Currline = context.line;
1107 		ret (dlines);
1108 	    }
1109 	    else {
1110 		write (2, &bell, 1);
1111 		break;
1112 	    }
1113 	case '=':
1114 	    kill_line ();
1115 	    promptlen = printd (Currline);
1116 	    fflush (stdout);
1117 	    break;
1118 	case 'n':
1119 	    lastp++;
1120 	case '/':
1121 	    if (nlines == 0) nlines++;
1122 	    kill_line ();
1123 	    pr ("/");
1124 	    promptlen = 1;
1125 	    fflush (stdout);
1126 	    if (lastp) {
1127 		write (2,"\r", 1);
1128 		search (NULL, f, nlines);	/* Use previous r.e. */
1129 	    }
1130 	    else {
1131 		ttyin (cmdbuf, 78, '/');
1132 		write (2, "\r", 1);
1133 		search (cmdbuf, f, nlines);
1134 	    }
1135 	    ret (dlines-1);
1136 	case '!':
1137 	    do_shell (filename);
1138 	    break;
1139 	case '?':
1140 	case 'h':
1141 	    if ((helpf = fopen (HELPFILE, "r")) == NULL)
1142 		error ("Can't open help file");
1143 	    if (noscroll) doclear ();
1144 	    copy_file (helpf);
1145 	    fclose (helpf);
1146 	    prompt (filename);
1147 	    break;
1148 	case 'v':	/* This case should go right before default */
1149 	    if (!no_intty) {
1150 		kill_line ();
1151 		cmdbuf[0] = '+';
1152 		scanstr (Currline - dlines < 0 ? 0
1153 				: Currline - (dlines + 1) / 2, &cmdbuf[1]);
1154 		pr ("vi "); pr (cmdbuf); putchar (' '); pr (fnames[fnum]);
1155 		execute (filename, VI, "vi", cmdbuf, fnames[fnum], 0);
1156 		break;
1157 	    }
1158 	default:
1159 	    if (dum_opt) {
1160    		kill_line ();
1161 		if (Senter && Sexit) {
1162 		    tputs (Senter, 1, putch);
1163 		    promptlen = pr ("[Press 'h' for instructions.]") + (2 * soglitch);
1164 		    tputs (Sexit, 1, putch);
1165 		}
1166 		else
1167 		    promptlen = pr ("[Press 'h' for instructions.]");
1168 		fflush (stdout);
1169 	    }
1170 	    else
1171 		write (2, &bell, 1);
1172 	    break;
1173 	}
1174 	if (done) break;
1175     }
1176     putchar ('\r');
1177 endsw:
1178     inwait = 0;
1179     notell++;
1180     if (MBIT == RAW && slow_tty) {
1181 	otty.sg_flags &= ~MBIT;
1182 	stty(fileno(stderr), &otty);
1183     }
1184     return (retval);
1185 }
1186 
1187 char ch;
1188 
1189 /*
1190  * Execute a colon-prefixed command.
1191  * Returns <0 if not a command that should cause
1192  * more of the file to be printed.
1193  */
1194 
1195 colon (filename, cmd, nlines)
1196 char *filename;
1197 int cmd;
1198 int nlines;
1199 {
1200 	if (cmd == 0)
1201 		ch = readch ();
1202 	else
1203 		ch = cmd;
1204 	lastcolon = ch;
1205 	switch (ch) {
1206 	case 'f':
1207 		kill_line ();
1208 		if (!no_intty)
1209 			promptlen = printf ("\"%s\" line %d", fnames[fnum], Currline);
1210 		else
1211 			promptlen = printf ("[Not a file] line %d", Currline);
1212 		fflush (stdout);
1213 		return (-1);
1214 	case 'n':
1215 		if (nlines == 0) {
1216 			if (fnum >= nfiles - 1)
1217 				end_it ();
1218 			nlines++;
1219 		}
1220 		putchar ('\r');
1221 		erase (0);
1222 		skipf (nlines);
1223 		return (0);
1224 	case 'p':
1225 		if (no_intty) {
1226 			write (2, &bell, 1);
1227 			return (-1);
1228 		}
1229 		putchar ('\r');
1230 		erase (0);
1231 		if (nlines == 0)
1232 			nlines++;
1233 		skipf (-nlines);
1234 		return (0);
1235 	case '!':
1236 		do_shell (filename);
1237 		return (-1);
1238 	case 'q':
1239 	case 'Q':
1240 		end_it ();
1241 	default:
1242 		write (2, &bell, 1);
1243 		return (-1);
1244 	}
1245 }
1246 
1247 /*
1248 ** Read a decimal number from the terminal. Set cmd to the non-digit which
1249 ** terminates the number.
1250 */
1251 
1252 number(cmd)
1253 char *cmd;
1254 {
1255 	register int i;
1256 
1257 	i = 0; ch = otty.sg_kill;
1258 	for (;;) {
1259 		ch = readch ();
1260 		if (ch >= '0' && ch <= '9')
1261 			i = i*10 + ch - '0';
1262 		else if (ch == otty.sg_kill)
1263 			i = 0;
1264 		else {
1265 			*cmd = ch;
1266 			break;
1267 		}
1268 	}
1269 	return (i);
1270 }
1271 
1272 do_shell (filename)
1273 char *filename;
1274 {
1275 	char cmdbuf[80];
1276 
1277 	kill_line ();
1278 	pr ("!");
1279 	fflush (stdout);
1280 	promptlen = 1;
1281 	if (lastp)
1282 		pr (shell_line);
1283 	else {
1284 		ttyin (cmdbuf, 78, '!');
1285 		if (expand (shell_line, cmdbuf)) {
1286 			kill_line ();
1287 			promptlen = printf ("!%s", shell_line);
1288 		}
1289 	}
1290 	fflush (stdout);
1291 	write (2, "\n", 1);
1292 	promptlen = 0;
1293 	shellp = 1;
1294 	execute (filename, shell, shell, "-c", shell_line, 0);
1295 }
1296 
1297 /*
1298 ** Search for nth ocurrence of regular expression contained in buf in the file
1299 */
1300 
1301 search (buf, file, n)
1302 char buf[];
1303 FILE *file;
1304 register int n;
1305 {
1306     long startline = Ftell (file);
1307     register long line1 = startline;
1308     register long line2 = startline;
1309     register long line3 = startline;
1310     register int lncount;
1311     int saveln, rv, re_exec();
1312     char *s, *re_comp();
1313 
1314     context.line = saveln = Currline;
1315     context.chrctr = startline;
1316     lncount = 0;
1317     if ((s = re_comp (buf)) != 0)
1318 	error (s);
1319     while (!feof (file)) {
1320 	line3 = line2;
1321 	line2 = line1;
1322 	line1 = Ftell (file);
1323 	rdline (file);
1324 	lncount++;
1325 	if ((rv = re_exec (Line)) == 1)
1326 		if (--n == 0) {
1327 		    if (lncount > 3 || (lncount > 1 && no_intty))
1328 		    {
1329 			pr ("\n");
1330 			if (clreol)
1331 			    cleareol ();
1332 			pr("...skipping\n");
1333 		    }
1334 		    if (!no_intty) {
1335 			Currline -= (lncount >= 3 ? 3 : lncount);
1336 			Fseek (file, line3);
1337 			if (noscroll)
1338 			    if (clreol) {
1339 				home ();
1340 				cleareol ();
1341 			    }
1342 			    else
1343 				doclear ();
1344 		    }
1345 		    else {
1346 			kill_line ();
1347 			if (noscroll)
1348 			    if (clreol) {
1349 			        home ();
1350 			        cleareol ();
1351 			    }
1352 			    else
1353 				doclear ();
1354 			pr (Line);
1355 			putchar ('\n');
1356 		    }
1357 		    break;
1358 		}
1359 	else if (rv == -1)
1360 	    error ("Regular expression botch");
1361     }
1362     if (feof (file)) {
1363 	if (!no_intty) {
1364 	    file->_flag &= ~_IOEOF; /* why doesn't fseek do this ??!!??! */
1365 	    Currline = saveln;
1366 	    Fseek (file, startline);
1367 	}
1368 	else {
1369 	    pr ("\nPattern not found\n");
1370 	    end_it ();
1371 	}
1372 	error ("Pattern not found");
1373     }
1374 }
1375 
1376 /*VARARGS2*/
1377 execute (filename, cmd, va_alist)
1378 char *filename;
1379 char *cmd;
1380 va_dcl
1381 {
1382 	int id;
1383 	int n;
1384 	va_list argp;
1385 
1386 	fflush (stdout);
1387 	reset_tty ();
1388 	for (n = 10; (id = fork ()) < 0 && n > 0; n--)
1389 	    sleep (5);
1390 	if (id == 0) {
1391 	    if (!isatty(0)) {
1392 		close(0);
1393 		open("/dev/tty", 0);
1394 	    }
1395 	    va_start(argp);
1396 	    execv (cmd, argp);
1397 	    write (2, "exec failed\n", 12);
1398 	    exit (1);
1399 	    va_end(argp);	/* balance {}'s for some UNIX's */
1400 	}
1401 	if (id > 0) {
1402 	    signal (SIGINT, SIG_IGN);
1403 	    signal (SIGQUIT, SIG_IGN);
1404 	    if (catch_susp)
1405 		signal(SIGTSTP, SIG_DFL);
1406 	    while (wait(0) > 0);
1407 	    signal (SIGINT, end_it);
1408 	    signal (SIGQUIT, onquit);
1409 	    if (catch_susp)
1410 		signal(SIGTSTP, onsusp);
1411 	} else
1412 	    write(2, "can't fork\n", 11);
1413 	set_tty ();
1414 	pr ("------------------------\n");
1415 	prompt (filename);
1416 }
1417 /*
1418 ** Skip n lines in the file f
1419 */
1420 
1421 skiplns (n, f)
1422 register int n;
1423 register FILE *f;
1424 {
1425     register char c;
1426 
1427     while (n > 0) {
1428 	while ((c = Getc (f)) != '\n')
1429 	    if (c == EOF)
1430 		return;
1431 	    n--;
1432 	    Currline++;
1433     }
1434 }
1435 
1436 /*
1437 ** Skip nskip files in the file list (from the command line). Nskip may be
1438 ** negative.
1439 */
1440 
1441 skipf (nskip)
1442 register int nskip;
1443 {
1444     if (nskip == 0) return;
1445     if (nskip > 0) {
1446 	if (fnum + nskip > nfiles - 1)
1447 	    nskip = nfiles - fnum - 1;
1448     }
1449     else if (within)
1450 	++fnum;
1451     fnum += nskip;
1452     if (fnum < 0)
1453 	fnum = 0;
1454     pr ("\n...Skipping ");
1455     pr ("\n");
1456     if (clreol)
1457 	cleareol ();
1458     pr ("...Skipping ");
1459     pr (nskip > 0 ? "to file " : "back to file ");
1460     pr (fnames[fnum]);
1461     pr ("\n");
1462     if (clreol)
1463 	cleareol ();
1464     pr ("\n");
1465     --fnum;
1466 }
1467 
1468 /*----------------------------- Terminal I/O -------------------------------*/
1469 
1470 initterm ()
1471 {
1472     char	buf[TBUFSIZ];
1473     static char	clearbuf[TBUFSIZ];
1474     char	*clearptr, *padstr;
1475     int		ldisc;
1476     int		lmode;
1477     char	*term;
1478     int		tgrp;
1479     struct winsize win;
1480 
1481 retry:
1482     if (!(no_tty = gtty(fileno(stdout), &otty))) {
1483 	if (ioctl(fileno(stdout), TIOCLGET, &lmode) < 0) {
1484 	    perror("TIOCLGET");
1485 	    exit(1);
1486 	}
1487 	docrterase = ((lmode & LCRTERA) != 0);
1488 	docrtkill = ((lmode & LCRTKIL) != 0);
1489 	/*
1490 	 * Wait until we're in the foreground before we save the
1491 	 * the terminal modes.
1492 	 */
1493 	if (ioctl(fileno(stdout), TIOCGPGRP, &tgrp) < 0) {
1494 	    perror("TIOCGPGRP");
1495 	    exit(1);
1496 	}
1497 	if (tgrp != getpgrp(0)) {
1498 	    kill(0, SIGTTOU);
1499 	    goto retry;
1500 	}
1501 	if ((term = getenv("TERM")) == 0 || tgetent(buf, term) <= 0) {
1502 	    dumb++; ul_opt = 0;
1503 	}
1504 	else {
1505 	    if (ioctl(fileno(stdout), TIOCGWINSZ, &win) < 0) {
1506 		Lpp = tgetnum("li");
1507 		Mcol = tgetnum("co");
1508 	    } else {
1509 		if ((Lpp = win.ws_row) == 0)
1510 		    Lpp = tgetnum("li");
1511 		if ((Mcol = win.ws_col) == 0)
1512 		    Mcol = tgetnum("co");
1513 	    }
1514 	    if ((Lpp <= 0) || tgetflag("hc")) {
1515 		hard++;	/* Hard copy terminal */
1516 		Lpp = 24;
1517 	    }
1518 	    if (tgetflag("xn"))
1519 		eatnl++; /* Eat newline at last column + 1; dec, concept */
1520 	    if (Mcol <= 0)
1521 		Mcol = 80;
1522 
1523 	    if (tailequ (fnames[0], "page") || !hard && tgetflag("ns"))
1524 		noscroll++;
1525 	    Wrap = tgetflag("am");
1526 	    bad_so = tgetflag ("xs");
1527 	    clearptr = clearbuf;
1528 	    eraseln = tgetstr("ce",&clearptr);
1529 	    Clear = tgetstr("cl", &clearptr);
1530 	    Senter = tgetstr("so", &clearptr);
1531 	    Sexit = tgetstr("se", &clearptr);
1532 	    if ((soglitch = tgetnum("sg")) < 0)
1533 		soglitch = 0;
1534 
1535 	    /*
1536 	     *  Set up for underlining:  some terminals don't need it;
1537 	     *  others have start/stop sequences, still others have an
1538 	     *  underline char sequence which is assumed to move the
1539 	     *  cursor forward one character.  If underline sequence
1540 	     *  isn't available, settle for standout sequence.
1541 	     */
1542 
1543 	    if (tgetflag("ul") || tgetflag("os"))
1544 		ul_opt = 0;
1545 	    if ((chUL = tgetstr("uc", &clearptr)) == NULL )
1546 		chUL = "";
1547 	    if (((ULenter = tgetstr("us", &clearptr)) == NULL ||
1548 	         (ULexit = tgetstr("ue", &clearptr)) == NULL) && !*chUL) {
1549 	        if ((ULenter = Senter) == NULL || (ULexit = Sexit) == NULL) {
1550 			ULenter = "";
1551 			ULexit = "";
1552 		} else
1553 			ulglitch = soglitch;
1554 	    } else {
1555 		if ((ulglitch = tgetnum("ug")) < 0)
1556 		    ulglitch = 0;
1557 	    }
1558 
1559 	    if (padstr = tgetstr("pc", &clearptr))
1560 		PC = *padstr;
1561 	    Home = tgetstr("ho",&clearptr);
1562 	    if (Home == 0 || *Home == '\0')
1563 	    {
1564 		if ((cursorm = tgetstr("cm", &clearptr)) != NULL) {
1565 		    strcpy(cursorhome, tgoto(cursorm, 0, 0));
1566 		    Home = cursorhome;
1567 	       }
1568 	    }
1569 	    EodClr = tgetstr("cd", &clearptr);
1570 	    if ((chBS = tgetstr("bc", &clearptr)) == NULL)
1571 		chBS = "\b";
1572 
1573 	}
1574 	if ((shell = getenv("SHELL")) == NULL)
1575 	    shell = "/bin/sh";
1576     }
1577     no_intty = gtty(fileno(stdin), &otty);
1578     gtty(fileno(stderr), &otty);
1579     savetty = otty;
1580     ospeed = otty.sg_ospeed;
1581     slow_tty = ospeed < B1200;
1582     hardtabs = (otty.sg_flags & TBDELAY) != XTABS;
1583     if (!no_tty) {
1584 	otty.sg_flags &= ~ECHO;
1585 	if (MBIT == CBREAK || !slow_tty)
1586 	    otty.sg_flags |= MBIT;
1587     }
1588 }
1589 
1590 readch ()
1591 {
1592 	char ch;
1593 	extern int errno;
1594 
1595 	errno = 0;
1596 	if (read (2, &ch, 1) <= 0)
1597 		if (errno != EINTR)
1598 			end_it();
1599 		else
1600 			ch = otty.sg_kill;
1601 	return (ch);
1602 }
1603 
1604 static char BS = '\b';
1605 static char *BSB = "\b \b";
1606 static char CARAT = '^';
1607 #define ERASEONECHAR \
1608     if (docrterase) \
1609 	write (2, BSB, sizeof(BSB)); \
1610     else \
1611 	write (2, &BS, sizeof(BS));
1612 
1613 ttyin (buf, nmax, pchar)
1614 char buf[];
1615 register int nmax;
1616 char pchar;
1617 {
1618     register char *sptr;
1619     register char ch;
1620     register int slash = 0;
1621     int	maxlen;
1622     char cbuf;
1623 
1624     sptr = buf;
1625     maxlen = 0;
1626     while (sptr - buf < nmax) {
1627 	if (promptlen > maxlen) maxlen = promptlen;
1628 	ch = readch ();
1629 	if (ch == '\\') {
1630 	    slash++;
1631 	}
1632 	else if ((ch == otty.sg_erase) && !slash) {
1633 	    if (sptr > buf) {
1634 		--promptlen;
1635 		ERASEONECHAR
1636 		--sptr;
1637 		if ((*sptr < ' ' && *sptr != '\n') || *sptr == RUBOUT) {
1638 		    --promptlen;
1639 		    ERASEONECHAR
1640 		}
1641 		continue;
1642 	    }
1643 	    else {
1644 		if (!eraseln) promptlen = maxlen;
1645 		longjmp (restore, 1);
1646 	    }
1647 	}
1648 	else if ((ch == otty.sg_kill) && !slash) {
1649 	    if (hard) {
1650 		show (ch);
1651 		putchar ('\n');
1652 		putchar (pchar);
1653 	    }
1654 	    else {
1655 		putchar ('\r');
1656 		putchar (pchar);
1657 		if (eraseln)
1658 		    erase (1);
1659 		else if (docrtkill)
1660 		    while (promptlen-- > 1)
1661 			write (2, BSB, sizeof(BSB));
1662 		promptlen = 1;
1663 	    }
1664 	    sptr = buf;
1665 	    fflush (stdout);
1666 	    continue;
1667 	}
1668 	if (slash && (ch == otty.sg_kill || ch == otty.sg_erase)) {
1669 	    ERASEONECHAR
1670 	    --sptr;
1671 	}
1672 	if (ch != '\\')
1673 	    slash = 0;
1674 	*sptr++ = ch;
1675 	if ((ch < ' ' && ch != '\n' && ch != ESC) || ch == RUBOUT) {
1676 	    ch += ch == RUBOUT ? -0100 : 0100;
1677 	    write (2, &CARAT, 1);
1678 	    promptlen++;
1679 	}
1680 	cbuf = ch;
1681 	if (ch != '\n' && ch != ESC) {
1682 	    write (2, &cbuf, 1);
1683 	    promptlen++;
1684 	}
1685 	else
1686 	    break;
1687     }
1688     *--sptr = '\0';
1689     if (!eraseln) promptlen = maxlen;
1690     if (sptr - buf >= nmax - 1)
1691 	error ("Line too long");
1692 }
1693 
1694 expand (outbuf, inbuf)
1695 char *outbuf;
1696 char *inbuf;
1697 {
1698     register char *instr;
1699     register char *outstr;
1700     register char ch;
1701     char temp[200];
1702     int changed = 0;
1703 
1704     instr = inbuf;
1705     outstr = temp;
1706     while ((ch = *instr++) != '\0')
1707 	switch (ch) {
1708 	case '%':
1709 	    if (!no_intty) {
1710 		strcpy (outstr, fnames[fnum]);
1711 		outstr += strlen (fnames[fnum]);
1712 		changed++;
1713 	    }
1714 	    else
1715 		*outstr++ = ch;
1716 	    break;
1717 	case '!':
1718 	    if (!shellp)
1719 		error ("No previous command to substitute for");
1720 	    strcpy (outstr, shell_line);
1721 	    outstr += strlen (shell_line);
1722 	    changed++;
1723 	    break;
1724 	case '\\':
1725 	    if (*instr == '%' || *instr == '!') {
1726 		*outstr++ = *instr++;
1727 		break;
1728 	    }
1729 	default:
1730 	    *outstr++ = ch;
1731 	}
1732     *outstr++ = '\0';
1733     strcpy (outbuf, temp);
1734     return (changed);
1735 }
1736 
1737 show (ch)
1738 register char ch;
1739 {
1740     char cbuf;
1741 
1742     if ((ch < ' ' && ch != '\n' && ch != ESC) || ch == RUBOUT) {
1743 	ch += ch == RUBOUT ? -0100 : 0100;
1744 	write (2, &CARAT, 1);
1745 	promptlen++;
1746     }
1747     cbuf = ch;
1748     write (2, &cbuf, 1);
1749     promptlen++;
1750 }
1751 
1752 error (mess)
1753 char *mess;
1754 {
1755     if (clreol)
1756 	cleareol ();
1757     else
1758 	kill_line ();
1759     promptlen += strlen (mess);
1760     if (Senter && Sexit) {
1761 	tputs (Senter, 1, putch);
1762 	pr(mess);
1763 	tputs (Sexit, 1, putch);
1764     }
1765     else
1766 	pr (mess);
1767     fflush(stdout);
1768     errors++;
1769     longjmp (restore, 1);
1770 }
1771 
1772 
1773 set_tty ()
1774 {
1775 	otty.sg_flags |= MBIT;
1776 	otty.sg_flags &= ~ECHO;
1777 	stty(fileno(stderr), &otty);
1778 }
1779 
1780 reset_tty ()
1781 {
1782     if (no_tty)
1783 	return;
1784     if (pstate) {
1785 	tputs(ULexit, 1, putch);
1786 	fflush(stdout);
1787 	pstate = 0;
1788     }
1789     otty.sg_flags |= ECHO;
1790     otty.sg_flags &= ~MBIT;
1791     stty(fileno(stderr), &savetty);
1792 }
1793 
1794 rdline (f)
1795 register FILE *f;
1796 {
1797     register char c;
1798     register char *p;
1799 
1800     p = Line;
1801     while ((c = Getc (f)) != '\n' && c != EOF && p - Line < LINSIZ - 1)
1802 	*p++ = c;
1803     if (c == '\n')
1804 	Currline++;
1805     *p = '\0';
1806 }
1807 
1808 /* Come here when we get a suspend signal from the terminal */
1809 
1810 onsusp ()
1811 {
1812     /* ignore SIGTTOU so we don't get stopped if csh grabs the tty */
1813     signal(SIGTTOU, SIG_IGN);
1814     reset_tty ();
1815     fflush (stdout);
1816     signal(SIGTTOU, SIG_DFL);
1817     /* Send the TSTP signal to suspend our process group */
1818     signal(SIGTSTP, SIG_DFL);
1819     sigsetmask(0);
1820     kill (0, SIGTSTP);
1821     /* Pause for station break */
1822 
1823     /* We're back */
1824     signal (SIGTSTP, onsusp);
1825     set_tty ();
1826     if (inwait)
1827 	    longjmp (restore);
1828 }
1829