xref: /original-bsd/usr.bin/more/command.c (revision a76afa45)
1 /*
2  * Copyright (c) 1988 Mark Nudleman
3  * Copyright (c) 1988 Regents of the University of California.
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms are permitted
7  * provided that the above copyright notice and this paragraph are
8  * duplicated in all such forms and that any documentation,
9  * advertising materials, and other materials related to such
10  * distribution and use acknowledge that the software was developed
11  * by Mark Nudleman and the University of California, Berkeley.  The
12  * name of Mark Nudleman or the
13  * University may not be used to endorse or promote products derived
14  * from this software without specific prior written permission.
15  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
17  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
18  */
19 
20 #ifndef lint
21 static char sccsid[] = "@(#)command.c	5.17 (Berkeley) 12/28/88";
22 #endif /* not lint */
23 
24 #include <sys/param.h>
25 #include <stdio.h>
26 #include <ctype.h>
27 #include <less.h>
28 
29 #define	NO_MCA		0
30 #define	MCA_DONE	1
31 #define	MCA_MORE	2
32 
33 extern int erase_char, kill_char, werase_char;
34 extern int ispipe;
35 extern int sigs;
36 extern int quit_at_eof;
37 extern int hit_eof;
38 extern int sc_width;
39 extern int sc_height;
40 extern int sc_window;
41 extern int curr_ac;
42 extern int ac;
43 extern int quitting;
44 extern int scroll;
45 extern int screen_trashed;	/* The screen has been overwritten */
46 
47 static char cmdbuf[120];	/* Buffer for holding a multi-char command */
48 static char *cp;		/* Pointer into cmdbuf */
49 static int cmd_col;		/* Current column of the multi-char command */
50 static int longprompt;		/* if stat command instead of prompt */
51 static int mca;			/* The multicharacter command (action) */
52 static int last_mca;		/* The previous mca */
53 static int number;		/* The number typed by the user */
54 static int wsearch;		/* Search for matches (1) or non-matches (0) */
55 
56 #define	CMD_RESET	cp = cmdbuf	/* reset command buffer to empty */
57 #define	CMD_EXEC	lower_left(); flush()
58 
59 /* backspace in command buffer. */
60 static
61 cmd_erase()
62 {
63 	/*
64 	 * backspace past beginning of the string: this usually means
65 	 * abort the command.
66 	 */
67 	if (cp == cmdbuf)
68 		return(1);
69 
70 	/* erase an extra character, for the carat. */
71 	if (CONTROL_CHAR(*--cp)) {
72 		backspace();
73 		--cmd_col;
74 	}
75 
76 	backspace();
77 	--cmd_col;
78 	return(0);
79 }
80 
81 /* set up the display to start a new multi-character command. */
82 start_mca(action, prompt)
83 	int action;
84 	char *prompt;
85 {
86 	lower_left();
87 	clear_eol();
88 	putstr(prompt);
89 	cmd_col = strlen(prompt);
90 	mca = action;
91 }
92 
93 /*
94  * process a single character of a multi-character command, such as
95  * a number, or the pattern of a search command.
96  */
97 static
98 cmd_char(c)
99 	int c;
100 {
101 	if (c == erase_char)
102 		return(cmd_erase());
103 	/* in this order, in case werase == erase_char */
104 	if (c == werase_char) {
105 		if (cp > cmdbuf) {
106 			while (isspace(cp[-1]) && !cmd_erase());
107 			while (!isspace(cp[-1]) && !cmd_erase());
108 			while (isspace(cp[-1]) && !cmd_erase());
109 		}
110 		return(cp == cmdbuf);
111 	}
112 	if (c == kill_char) {
113 		while (!cmd_erase());
114 		return(1);
115 	}
116 	/*
117 	 * No room in the command buffer, or no room on the screen;
118 	 * {{ Could get fancy here; maybe shift the displayed line
119 	 * and make room for more chars, like ksh. }}
120 	 */
121 	if (cp >= &cmdbuf[sizeof(cmdbuf)-1] || cmd_col >= sc_width-3)
122 		bell();
123 	else {
124 		*cp++ = c;
125 		if (CONTROL_CHAR(c)) {
126 			putchr('^');
127 			cmd_col++;
128 			c = CARAT_CHAR(c);
129 		}
130 		putchr(c);
131 		cmd_col++;
132 	}
133 	return(0);
134 }
135 
136 prompt()
137 {
138 	extern int linenums, short_file;
139 	extern char *current_name, *firstsearch, *next_name;
140 	off_t len, pos, ch_length(), position(), forw_line();
141 	char pbuf[40];
142 
143 	/*
144 	 * if nothing is displayed yet, display starting from line 1;
145 	 * if search string provided, go there instead.
146 	 */
147 	if (position(TOP) == NULL_POSITION) {
148 		if (forw_line((off_t)0) == NULL_POSITION)
149 			return(0);
150 		if (!firstsearch || !search(1, firstsearch, 1, 1))
151 			jump_back(1);
152 	}
153 	else if (screen_trashed)
154 		repaint();
155 
156 	/* if no -e flag and we've hit EOF on the last file, quit. */
157 	if ((!quit_at_eof || short_file) && hit_eof && curr_ac + 1 >= ac)
158 		quit();
159 
160 	/* select the proper prompt and display it. */
161 	lower_left();
162 	clear_eol();
163 	if (longprompt) {
164 		so_enter();
165 		putstr(current_name);
166 		putstr(":");
167 		if (!ispipe) {
168 			(void)sprintf(pbuf, " file %d/%d", curr_ac + 1, ac);
169 			putstr(pbuf);
170 		}
171 		if (linenums) {
172 			(void)sprintf(pbuf, " line %d", currline(BOTTOM));
173 			putstr(pbuf);
174 		}
175 		if ((pos = position(BOTTOM)) != NULL_POSITION) {
176 			(void)sprintf(pbuf, " byte %ld", pos);
177 			putstr(pbuf);
178 			if (!ispipe && (len = ch_length())) {
179 				(void)sprintf(pbuf, "/%ld pct %ld%%",
180 				    len, ((100 * pos) / len));
181 				putstr(pbuf);
182 			}
183 		}
184 		so_exit();
185 		longprompt = 0;
186 	}
187 	else {
188 		so_enter();
189 		putstr(current_name);
190 		if (hit_eof)
191 			if (next_name) {
192 				(void)sprintf(pbuf, ": END (next file: %s)",
193 				    next_name);
194 				putstr(pbuf);
195 			}
196 			else
197 				putstr(": END");
198 		else if (!ispipe &&
199 		    (pos = position(BOTTOM)) != NULL_POSITION &&
200 		    (len = ch_length())) {
201 			(void)sprintf(pbuf, " (%ld%%)", ((100 * pos) / len));
202 			putstr(pbuf);
203 		}
204 		so_exit();
205 	}
206 	return(1);
207 }
208 
209 /* get command character. */
210 static
211 getcc()
212 {
213 	extern int cmdstack;
214 	int ch;
215 
216 	/* left over from error() routine. */
217 	if (cmdstack) {
218 		ch = cmdstack;
219 		cmdstack = NULL;
220 		return(ch);
221 	}
222 	if (cp > cmdbuf && position(TOP) == NULL_POSITION) {
223 		/*
224 		 * Command is incomplete, so try to complete it.
225 		 * There are only two cases:
226 		 * 1. We have "/string" but no newline.  Add the \n.
227 		 * 2. We have a number but no command.  Treat as #g.
228 		 * (This is all pretty hokey.)
229 		 */
230 		if (mca != A_DIGIT)
231 			/* Not a number; must be search string */
232 			return('\n');
233 		else
234 			/* A number; append a 'g' */
235 			return('g');
236 	}
237 	return(getchr());
238 }
239 
240 /* execute a multicharacter command. */
241 static
242 exec_mca()
243 {
244 	extern int file;
245 	extern char *tagfile;
246 	register char *p;
247 	char *glob();
248 
249 	*cp = '\0';
250 	CMD_EXEC;
251 	switch (mca) {
252 	case A_F_SEARCH:
253 		(void)search(1, cmdbuf, number, wsearch);
254 		break;
255 	case A_B_SEARCH:
256 		(void)search(0, cmdbuf, number, wsearch);
257 		break;
258 	case A_EXAMINE:
259 		for (p = cmdbuf; isspace(*p); ++p);
260 		(void)edit(glob(p));
261 		break;
262 	case A_TAGFILE:
263 		for (p = cmdbuf; isspace(*p); ++p);
264 		findtag(p);
265 		if (tagfile == NULL)
266 			break;
267 		if (edit(tagfile))
268 			(void)tagsearch();
269 		break;
270 	}
271 }
272 
273 /* add a character to a multi-character command. */
274 static
275 mca_char(c)
276 	int c;
277 {
278 	switch (mca) {
279 	case 0:			/* not in a multicharacter command. */
280 	case A_PREFIX:		/* in the prefix of a command. */
281 		return(NO_MCA);
282 	case A_DIGIT:
283 		/*
284 		 * Entering digits of a number.
285 		 * Terminated by a non-digit.
286 		 */
287 		if (!isascii(c) || !isdigit(c) &&
288 		    c != erase_char && c != kill_char && c != werase_char) {
289 			/*
290 			 * Not part of the number.
291 			 * Treat as a normal command character.
292 			 */
293 			*cp = '\0';
294 			number = atoi(cmdbuf);
295 			CMD_RESET;
296 			mca = 0;
297 			return(NO_MCA);
298 		}
299 		break;
300 	}
301 
302 	/*
303 	 * Any other multicharacter command
304 	 * is terminated by a newline.
305 	 */
306 	if (c == '\n' || c == '\r') {
307 		exec_mca();
308 		return(MCA_DONE);
309 	}
310 
311 	/* append the char to the command buffer. */
312 	if (cmd_char(c))
313 		return(MCA_DONE);
314 
315 	return(MCA_MORE);
316 }
317 
318 /*
319  * Main command processor.
320  * Accept and execute commands until a quit command, then return.
321  */
322 commands()
323 {
324 	register int c;
325 	register int action;
326 
327 	last_mca = 0;
328 	scroll = (sc_height + 1) / 2;
329 
330 	for (;;) {
331 		mca = 0;
332 		number = 0;
333 
334 		/*
335 		 * See if any signals need processing.
336 		 */
337 		if (sigs) {
338 			psignals();
339 			if (quitting)
340 				quit();
341 		}
342 		/*
343 		 * Display prompt and accept a character.
344 		 */
345 		CMD_RESET;
346 		if (!prompt()) {
347 			next_file(1);
348 			continue;
349 		}
350 		noprefix();
351 		c = getcc();
352 
353 again:		if (sigs)
354 			continue;
355 
356 		/*
357 		 * If we are in a multicharacter command, call mca_char.
358 		 * Otherwise we call cmd_decode to determine the
359 		 * action to be performed.
360 		 */
361 		if (mca)
362 			switch (mca_char(c)) {
363 			case MCA_MORE:
364 				/*
365 				 * Need another character.
366 				 */
367 				c = getcc();
368 				goto again;
369 			case MCA_DONE:
370 				/*
371 				 * Command has been handled by mca_char.
372 				 * Start clean with a prompt.
373 				 */
374 				continue;
375 			case NO_MCA:
376 				/*
377 				 * Not a multi-char command
378 				 * (at least, not anymore).
379 				 */
380 				break;
381 			}
382 
383 		/* decode the command character and decide what to do. */
384 		switch (action = cmd_decode(c)) {
385 		case A_DIGIT:		/* first digit of a number */
386 			start_mca(A_DIGIT, ":");
387 			goto again;
388 		case A_F_SCREEN:	/* forward one screen */
389 			CMD_EXEC;
390 			if (number <= 0 && (number = sc_window) <= 0)
391 				number = sc_height - 1;
392 			forward(number, 1);
393 			break;
394 		case A_B_SCREEN:	/* backward one screen */
395 			CMD_EXEC;
396 			if (number <= 0 && (number = sc_window) <= 0)
397 				number = sc_height - 1;
398 			backward(number, 1);
399 			break;
400 		case A_F_LINE:		/* forward N (default 1) line */
401 			CMD_EXEC;
402 			forward(number <= 0 ? 1 : number, 0);
403 			break;
404 		case A_B_LINE:		/* backward N (default 1) line */
405 			CMD_EXEC;
406 			backward(number <= 0 ? 1 : number, 0);
407 			break;
408 		case A_F_SCROLL:	/* forward N lines */
409 			CMD_EXEC;
410 			if (number > 0)
411 				scroll = number;
412 			forward(scroll, 0);
413 			break;
414 		case A_B_SCROLL:	/* backward N lines */
415 			CMD_EXEC;
416 			if (number > 0)
417 				scroll = number;
418 			backward(scroll, 0);
419 			break;
420 		case A_FREPAINT:	/* flush buffers and repaint */
421 			if (!ispipe) {
422 				ch_init(0, 0);
423 				clr_linenum();
424 			}
425 			/* FALLTHROUGH */
426 		case A_REPAINT:		/* repaint the screen */
427 			CMD_EXEC;
428 			repaint();
429 			break;
430 		case A_GOLINE:		/* go to line N, default 1 */
431 			CMD_EXEC;
432 			if (number <= 0)
433 				number = 1;
434 			jump_back(number);
435 			break;
436 		case A_PERCENT:		/* go to percent of file */
437 			CMD_EXEC;
438 			if (number < 0)
439 				number = 0;
440 			else if (number > 100)
441 				number = 100;
442 			jump_percent(number);
443 			break;
444 		case A_GOEND:		/* go to line N, default end */
445 			CMD_EXEC;
446 			if (number <= 0)
447 				jump_forw();
448 			else
449 				jump_back(number);
450 			break;
451 		case A_STAT:		/* print file name, etc. */
452 			longprompt = 1;
453 			continue;
454 		case A_QUIT:		/* exit */
455 			quit();
456 		case A_F_SEARCH:	/* search for a pattern */
457 		case A_B_SEARCH:
458 			if (number <= 0)
459 				number = 1;
460 			start_mca(action, (action==A_F_SEARCH) ? "/" : "?");
461 			last_mca = mca;
462 			wsearch = 1;
463 			c = getcc();
464 			if (c == '!') {
465 				/*
466 				 * Invert the sense of the search; set wsearch
467 				 * to 0 and get a new character for the start
468 				 * of the pattern.
469 				 */
470 				start_mca(action,
471 				    (action == A_F_SEARCH) ? "!/" : "!?");
472 				wsearch = 0;
473 				c = getcc();
474 			}
475 			goto again;
476 		case A_AGAIN_SEARCH:		/* repeat previous search */
477 			if (number <= 0)
478 				number = 1;
479 			if (wsearch)
480 				start_mca(last_mca,
481 				    (last_mca == A_F_SEARCH) ? "/" : "?");
482 			else
483 				start_mca(last_mca,
484 				    (last_mca == A_F_SEARCH) ? "!/" : "!?");
485 			CMD_EXEC;
486 			(void)search(mca == A_F_SEARCH, (char *)NULL,
487 			    number, wsearch);
488 			break;
489 		case A_HELP:			/* help */
490 			lower_left();
491 			clear_eol();
492 			putstr("help");
493 			CMD_EXEC;
494 			help();
495 			break;
496 		case A_TAGFILE:			/* tag a new file */
497 			CMD_RESET;
498 			start_mca(A_TAGFILE, "Tag: ");
499 			c = getcc();
500 			goto again;
501 		case A_FILE_LIST:		/* show list of file names */
502 			CMD_EXEC;
503 			showlist();
504 			repaint();
505 			break;
506 		case A_EXAMINE:			/* edit a new file */
507 			CMD_RESET;
508 			start_mca(A_EXAMINE, "Examine: ");
509 			c = getcc();
510 			goto again;
511 		case A_VISUAL:			/* invoke the editor */
512 			if (ispipe) {
513 				error("Cannot edit standard input");
514 				break;
515 			}
516 			CMD_EXEC;
517 			editfile();
518 			ch_init(0, 0);
519 			clr_linenum();
520 			break;
521 		case A_NEXT_FILE:		/* examine next file */
522 			if (number <= 0)
523 				number = 1;
524 			next_file(number);
525 			break;
526 		case A_PREV_FILE:		/* examine previous file */
527 			if (number <= 0)
528 				number = 1;
529 			prev_file(number);
530 			break;
531 		case A_SETMARK:			/* set a mark */
532 			lower_left();
533 			clear_eol();
534 			start_mca(A_SETMARK, "mark: ");
535 			c = getcc();
536 			if (c == erase_char || c == kill_char)
537 				break;
538 			setmark(c);
539 			break;
540 		case A_GOMARK:			/* go to mark */
541 			lower_left();
542 			clear_eol();
543 			start_mca(A_GOMARK, "goto mark: ");
544 			c = getcc();
545 			if (c == erase_char || c == kill_char)
546 				break;
547 			gomark(c);
548 			break;
549 		case A_PREFIX:
550 			/*
551 			 * The command is incomplete (more chars are needed).
552 			 * Display the current char so the user knows what's
553 			 * going on and get another character.
554 			 */
555 			if (mca != A_PREFIX)
556 				start_mca(A_PREFIX, "");
557 			if (CONTROL_CHAR(c)) {
558 				putchr('^');
559 				c = CARAT_CHAR(c);
560 			}
561 			putchr(c);
562 			c = getcc();
563 			goto again;
564 		default:
565 			bell();
566 			break;
567 		}
568 	}
569 }
570 
571 static
572 editfile()
573 {
574 	extern char *current_file;
575 	static int dolinenumber;
576 	static char *editor;
577 	int c;
578 	char buf[MAXPATHLEN * 2 + 20], *getenv();
579 
580 	if (editor == NULL) {
581 		editor = getenv("EDITOR");
582 		/* pass the line number to vi */
583 		if (editor == NULL || *editor == '\0') {
584 #define	EDIT_PGM	"/usr/ucb/vi"
585 			editor = EDIT_PGM;
586 			dolinenumber = 1;
587 		}
588 		else
589 			dolinenumber = 0;
590 	}
591 	if (dolinenumber && (c = currline(MIDDLE)))
592 		(void)sprintf(buf, "%s +%d %s", editor, c, current_file);
593 	else
594 		(void)sprintf(buf, "%s %s", editor, current_file);
595 	lsystem(buf);
596 }
597 
598 static
599 showlist()
600 {
601 	extern int sc_width;
602 	extern char **av;
603 	register int indx, width;
604 	int len;
605 	char *p;
606 
607 	if (ac <= 0) {
608 		error("No files provided as arguments.");
609 		return;
610 	}
611 	for (width = indx = 0; indx < ac;) {
612 		p = strcmp(av[indx], "-") ? av[indx] : "stdin";
613 		len = strlen(p) + 1;
614 		if (curr_ac == indx)
615 			len += 2;
616 		if (width + len + 1 >= sc_width) {
617 			if (!width) {
618 				if (curr_ac == indx)
619 					putchr('[');
620 				putstr(p);
621 				if (curr_ac == indx)
622 					putchr(']');
623 				++indx;
624 			}
625 			width = 0;
626 			putchr('\n');
627 			continue;
628 		}
629 		if (width)
630 			putchr(' ');
631 		if (curr_ac == indx)
632 			putchr('[');
633 		putstr(p);
634 		if (curr_ac == indx)
635 			putchr(']');
636 		width += len;
637 		++indx;
638 	}
639 	putchr('\n');
640 	error((char *)NULL);
641 }
642