xref: /openbsd-src/bin/ed/main.c (revision a28daedfc357b214be5c701aa8ba8adb29a7f1c2)
1 /*	$OpenBSD: main.c,v 1.32 2009/01/28 22:17:30 sobrado Exp $	*/
2 /*	$NetBSD: main.c,v 1.3 1995/03/21 09:04:44 cgd Exp $	*/
3 
4 /* main.c: This file contains the main control and user-interface routines
5    for the ed line editor. */
6 /*-
7  * Copyright (c) 1993 Andrew Moore, Talke Studio.
8  * All rights reserved.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #ifndef lint
33 char *copyright =
34 "@(#) Copyright (c) 1993 Andrew Moore, Talke Studio. \n\
35  All rights reserved.\n";
36 #endif /* not lint */
37 
38 #ifndef lint
39 #if 0
40 static char *rcsid = "@(#)main.c,v 1.1 1994/02/01 00:34:42 alm Exp";
41 #else
42 static char rcsid[] = "$OpenBSD: main.c,v 1.32 2009/01/28 22:17:30 sobrado Exp $";
43 #endif
44 #endif /* not lint */
45 
46 /*
47  * CREDITS
48  *
49  *	This program is based on the editor algorithm described in
50  *	Brian W. Kernighan and P. J. Plauger's book "Software Tools
51  *	in Pascal," Addison-Wesley, 1981.
52  *
53  *	The buffering algorithm is attributed to Rodney Ruddock of
54  *	the University of Guelph, Guelph, Ontario.
55  *
56  *	The cbc.c encryption code is adapted from
57  *	the bdes program by Matt Bishop of Dartmouth College,
58  *	Hanover, NH.
59  *
60  */
61 
62 #include <sys/ioctl.h>
63 #include <sys/stat.h>
64 #include <sys/wait.h>
65 #include <ctype.h>
66 #include <setjmp.h>
67 #include <unistd.h>
68 #include <pwd.h>
69 
70 #include "ed.h"
71 
72 
73 #ifdef _POSIX_SOURCE
74 sigjmp_buf env;
75 #else
76 jmp_buf env;
77 #endif
78 
79 /* static buffers */
80 char stdinbuf[1];		/* stdin buffer */
81 char *shcmd;			/* shell command buffer */
82 int shcmdsz;			/* shell command buffer size */
83 int shcmdi;			/* shell command buffer index */
84 char *ibuf;			/* ed command-line buffer */
85 int ibufsz;			/* ed command-line buffer size */
86 char *ibufp;			/* pointer to ed command-line buffer */
87 
88 /* global flags */
89 int des = 0;			/* if set, use crypt(3) for i/o */
90 int garrulous = 0;		/* if set, print all error messages */
91 int isbinary;			/* if set, buffer contains ASCII NULs */
92 int isglobal;			/* if set, doing a global command */
93 int modified;			/* if set, buffer modified since last write */
94 int mutex = 0;			/* if set, signals set "sigflags" */
95 int red = 0;			/* if set, restrict shell/directory access */
96 int scripted = 0;		/* if set, suppress diagnostics */
97 int sigflags = 0;		/* if set, signals received while mutex set */
98 int interactive = 0;		/* if set, we are in interactive mode */
99 
100 /* if set, signal handlers are enabled */
101 volatile sig_atomic_t sigactive = 0;
102 
103 char old_filename[MAXPATHLEN] = "";	/* default filename */
104 int current_addr;		/* current address in editor buffer */
105 int addr_last;			/* last address in editor buffer */
106 int lineno;			/* script line number */
107 char *prompt;			/* command-line prompt */
108 char *dps = "*";		/* default command-line prompt */
109 
110 char *usage = "usage: %s [-] [-sx] [-p string] [file]\n";
111 
112 char *home;		/* home directory */
113 
114 void
115 seterrmsg(char *s)
116 {
117 	strlcpy(errmsg, s, sizeof(errmsg));
118 }
119 
120 /* ed: line editor */
121 int
122 main(volatile int argc, char ** volatile argv)
123 {
124 	int c, n;
125 	int status = 0;
126 
127 	home = getenv("HOME");
128 
129 	red = (n = strlen(argv[0])) > 2 && argv[0][n - 3] == 'r';
130 top:
131 	while ((c = getopt(argc, argv, "p:sx")) != -1)
132 		switch (c) {
133 		case 'p':				/* set prompt */
134 			prompt = optarg;
135 			break;
136 		case 's':				/* run script */
137 			scripted = 1;
138 			break;
139 		case 'x':				/* use crypt */
140 #ifdef DES
141 			des = get_keyword();
142 #else
143 			fprintf(stderr, "crypt unavailable\n?\n");
144 #endif
145 			break;
146 
147 		default:
148 			fprintf(stderr, usage, argv[0]);
149 			exit(1);
150 		}
151 	argv += optind;
152 	argc -= optind;
153 	if (argc && **argv == '-') {
154 		scripted = 1;
155 		if (argc > 1) {
156 			optind = 1;
157 			goto top;
158 		}
159 		argv++;
160 		argc--;
161 	}
162 
163 	if (!(interactive = isatty(0))) {
164 		struct stat sb;
165 
166 		/* assert: pipes show up as fifo's when fstat'd */
167 		if (fstat(0, &sb) || !S_ISFIFO(sb.st_mode)) {
168 			if (lseek(0, 0, SEEK_CUR)) {
169 				interactive = 1;
170 				setlinebuf(stdout);
171 			}
172 		}
173 	}
174 
175 	/* assert: reliable signals! */
176 #ifdef SIGWINCH
177 	handle_winch(SIGWINCH);
178 	if (isatty(0))
179 		signal(SIGWINCH, handle_winch);
180 #endif
181 	signal(SIGHUP, signal_hup);
182 	signal(SIGQUIT, SIG_IGN);
183 	signal(SIGINT, signal_int);
184 #ifdef _POSIX_SOURCE
185 	if (status = sigsetjmp(env, 1))
186 #else
187 	if ((status = setjmp(env)) != 0)
188 #endif
189 	{
190 		fputs("\n?\n", stderr);
191 		seterrmsg("interrupt");
192 	} else {
193 		init_buffers();
194 		sigactive = 1;			/* enable signal handlers */
195 		if (argc && **argv && is_legal_filename(*argv)) {
196 			if (read_file(*argv, 0) < 0 && !interactive)
197 				quit(2);
198 			else if (**argv != '!')
199 				strlcpy(old_filename, *argv,
200 				    sizeof old_filename);
201 		} else if (argc) {
202 			fputs("?\n", stderr);
203 			if (**argv == '\0')
204 				seterrmsg("invalid filename");
205 			if (!interactive)
206 				quit(2);
207 		}
208 	}
209 	for (;;) {
210 		if (status < 0 && garrulous)
211 			fprintf(stderr, "%s\n", errmsg);
212 		if (prompt) {
213 			fputs(prompt, stdout);
214 			fflush(stdout);
215 		}
216 		if ((n = get_tty_line()) < 0) {
217 			status = ERR;
218 			continue;
219 		} else if (n == 0) {
220 			if (modified && !scripted) {
221 				fputs("?\n", stderr);
222 				seterrmsg("warning: file modified");
223 				if (!interactive) {
224 					fprintf(stderr, garrulous ?
225 					    "script, line %d: %s\n" :
226 					    "", lineno, errmsg);
227 					quit(2);
228 				}
229 				clearerr(stdin);
230 				modified = 0;
231 				status = EMOD;
232 				continue;
233 			} else
234 				quit(0);
235 		} else if (ibuf[n - 1] != '\n') {
236 			/* discard line */
237 			seterrmsg("unexpected end-of-file");
238 			clearerr(stdin);
239 			status = ERR;
240 			continue;
241 		}
242 		isglobal = 0;
243 		if ((status = extract_addr_range()) >= 0 &&
244 		    (status = exec_command()) >= 0)
245 			if (!status || (status &&
246 			    (status = display_lines(current_addr, current_addr,
247 				status)) >= 0))
248 				continue;
249 		switch (status) {
250 		case EOF:
251 			quit(0);
252 		case EMOD:
253 			modified = 0;
254 			fputs("?\n", stderr);		/* give warning */
255 			seterrmsg("warning: file modified");
256 			if (!interactive) {
257 				fprintf(stderr, garrulous ?
258 				    "script, line %d: %s\n" :
259 				    "", lineno, errmsg);
260 				quit(2);
261 			}
262 			break;
263 		case FATAL:
264 			if (!interactive)
265 				fprintf(stderr, garrulous ?
266 				    "script, line %d: %s\n" : "",
267 				    lineno, errmsg);
268 			else
269 				fprintf(stderr, garrulous ? "%s\n" : "",
270 				    errmsg);
271 			quit(3);
272 		default:
273 			fputs("?\n", stderr);
274 			if (!interactive) {
275 				fprintf(stderr, garrulous ?
276 				    "script, line %d: %s\n" : "",
277 				    lineno, errmsg);
278 				quit(2);
279 			}
280 			break;
281 		}
282 	}
283 	/*NOTREACHED*/
284 }
285 
286 int first_addr, second_addr, addr_cnt;
287 
288 /* extract_addr_range: get line addresses from the command buffer until an
289    illegal address is seen; return status */
290 int
291 extract_addr_range(void)
292 {
293 	int addr;
294 
295 	addr_cnt = 0;
296 	first_addr = second_addr = current_addr;
297 	while ((addr = next_addr()) >= 0) {
298 		addr_cnt++;
299 		first_addr = second_addr;
300 		second_addr = addr;
301 		if (*ibufp != ',' && *ibufp != ';')
302 			break;
303 		else if (*ibufp++ == ';')
304 			current_addr = addr;
305 	}
306 	if ((addr_cnt = min(addr_cnt, 2)) == 1 || second_addr != addr)
307 		first_addr = second_addr;
308 	return (addr == ERR) ? ERR : 0;
309 }
310 
311 
312 #define	SKIP_BLANKS() \
313 	do { \
314 		while (isspace(*ibufp) && *ibufp != '\n') \
315 			ibufp++; \
316 	} while (0)
317 
318 #define MUST_BE_FIRST() \
319 	do { \
320 		if (!first) { \
321 			seterrmsg("invalid address"); \
322 			return ERR; \
323 		} \
324 	} while (0)
325 
326 
327 /*  next_addr: return the next line address in the command buffer */
328 int
329 next_addr(void)
330 {
331 	char *hd;
332 	int addr = current_addr;
333 	int n;
334 	int first = 1;
335 	int c;
336 
337 	SKIP_BLANKS();
338 	for (hd = ibufp;; first = 0)
339 		switch ((c = *ibufp)) {
340 		case '+':
341 		case '\t':
342 		case ' ':
343 		case '-':
344 		case '^':
345 			ibufp++;
346 			SKIP_BLANKS();
347 			if (isdigit(*ibufp)) {
348 				STRTOI(n, ibufp);
349 				addr += (c == '-' || c == '^') ? -n : n;
350 			} else if (!isspace(c))
351 				addr += (c == '-' || c == '^') ? -1 : 1;
352 			break;
353 		case '0': case '1': case '2':
354 		case '3': case '4': case '5':
355 		case '6': case '7': case '8': case '9':
356 			MUST_BE_FIRST();
357 			STRTOI(addr, ibufp);
358 			break;
359 		case '.':
360 		case '$':
361 			MUST_BE_FIRST();
362 			ibufp++;
363 			addr = (c == '.') ? current_addr : addr_last;
364 			break;
365 		case '/':
366 		case '?':
367 			MUST_BE_FIRST();
368 			if ((addr = get_matching_node_addr(
369 			    get_compiled_pattern(), c == '/')) < 0)
370 				return ERR;
371 			else if (c == *ibufp)
372 				ibufp++;
373 			break;
374 		case '\'':
375 			MUST_BE_FIRST();
376 			ibufp++;
377 			if ((addr = get_marked_node_addr(*ibufp++)) < 0)
378 				return ERR;
379 			break;
380 		case '%':
381 		case ',':
382 		case ';':
383 			if (first) {
384 				ibufp++;
385 				addr_cnt++;
386 				second_addr = (c == ';') ? current_addr : 1;
387 				addr = addr_last;
388 				break;
389 			}
390 			/* FALLTHROUGH */
391 		default:
392 			if (ibufp == hd)
393 				return EOF;
394 			else if (addr < 0 || addr_last < addr) {
395 				seterrmsg("invalid address");
396 				return ERR;
397 			} else
398 				return addr;
399 		}
400 	/* NOTREACHED */
401 }
402 
403 
404 #ifdef BACKWARDS
405 /* GET_THIRD_ADDR: get a legal address from the command buffer */
406 #define GET_THIRD_ADDR(addr) \
407 	do { \
408 		int ol1, ol2; \
409 		\
410 		ol1 = first_addr; \
411 		ol2 = second_addr; \
412 		if (extract_addr_range() < 0) \
413 			return ERR; \
414 		else if (addr_cnt == 0) { \
415 			seterrmsg("destination expected"); \
416 			return ERR; \
417 		} else if (second_addr < 0 || addr_last < second_addr) { \
418 			seterrmsg("invalid address"); \
419 			return ERR; \
420 		} \
421 		addr = second_addr; \
422 		first_addr = ol1; \
423 		second_addr = ol2; \
424 	} while (0)
425 
426 #else	/* BACKWARDS */
427 /* GET_THIRD_ADDR: get a legal address from the command buffer */
428 #define GET_THIRD_ADDR(addr) \
429 	do { \
430 		int ol1, ol2; \
431 		\
432 		ol1 = first_addr; \
433 		ol2 = second_addr; \
434 		if (extract_addr_range() < 0) \
435 			return ERR; \
436 		if (second_addr < 0 || addr_last < second_addr) { \
437 			seterrmsg("invalid address"); \
438 			return ERR; \
439 		} \
440 		addr = second_addr; \
441 		first_addr = ol1; \
442 		second_addr = ol2; \
443 	} while (0)
444 #endif
445 
446 
447 /* GET_COMMAND_SUFFIX: verify the command suffix in the command buffer */
448 #define GET_COMMAND_SUFFIX() \
449 	do { \
450 		int done = 0; \
451 		do { \
452 			switch (*ibufp) { \
453 			case 'p': \
454 				gflag |= GPR; \
455 				ibufp++; \
456 				break; \
457 			case 'l': \
458 				gflag |= GLS; \
459 				ibufp++; \
460 				break; \
461 			case 'n': \
462 				gflag |= GNP; \
463 				ibufp++; \
464 				break; \
465 			default: \
466 				done++; \
467 			} \
468 		} while (!done); \
469 		if (*ibufp++ != '\n') { \
470 			seterrmsg("invalid command suffix"); \
471 			return ERR; \
472 		} \
473 	} while (0)
474 
475 /* sflags */
476 #define SGG 001		/* complement previous global substitute suffix */
477 #define SGP 002		/* complement previous print suffix */
478 #define SGR 004		/* use last regex instead of last pat */
479 #define SGF 010		/* repeat last substitution */
480 
481 int patlock = 0;	/* if set, pattern not freed by get_compiled_pattern() */
482 
483 volatile sig_atomic_t rows = 22;	/* scroll length: ws_row - 2 */
484 volatile sig_atomic_t cols = 72;	/* wrap column */
485 
486 /* exec_command: execute the next command in command buffer; return print
487    request, if any */
488 int
489 exec_command(void)
490 {
491 	extern int u_current_addr;
492 	extern int u_addr_last;
493 
494 	static pattern_t *pat = NULL;
495 	static int sgflag = 0;
496 	static int sgnum = 0;
497 
498 	pattern_t *tpat;
499 	char *fnp;
500 	int gflag = 0;
501 	int sflags = 0;
502 	int addr = 0;
503 	int n = 0;
504 	int c;
505 
506 	SKIP_BLANKS();
507 	switch ((c = *ibufp++)) {
508 	case 'a':
509 		GET_COMMAND_SUFFIX();
510 		if (!isglobal) clear_undo_stack();
511 		if (append_lines(second_addr) < 0)
512 			return ERR;
513 		break;
514 	case 'c':
515 		if (check_addr_range(current_addr, current_addr) < 0)
516 			return ERR;
517 		GET_COMMAND_SUFFIX();
518 		if (!isglobal) clear_undo_stack();
519 		if (delete_lines(first_addr, second_addr) < 0 ||
520 		    append_lines(current_addr) < 0)
521 			return ERR;
522 		break;
523 	case 'd':
524 		if (check_addr_range(current_addr, current_addr) < 0)
525 			return ERR;
526 		GET_COMMAND_SUFFIX();
527 		if (!isglobal) clear_undo_stack();
528 		if (delete_lines(first_addr, second_addr) < 0)
529 			return ERR;
530 		else if ((addr = INC_MOD(current_addr, addr_last)) != 0)
531 			current_addr = addr;
532 		break;
533 	case 'e':
534 		if (modified && !scripted)
535 			return EMOD;
536 		/* FALLTHROUGH */
537 	case 'E':
538 		if (addr_cnt > 0) {
539 			seterrmsg("unexpected address");
540 			return ERR;
541 		} else if (!isspace(*ibufp)) {
542 			seterrmsg("unexpected command suffix");
543 			return ERR;
544 		} else if ((fnp = get_filename()) == NULL)
545 			return ERR;
546 		GET_COMMAND_SUFFIX();
547 		if (delete_lines(1, addr_last) < 0)
548 			return ERR;
549 		clear_undo_stack();
550 		if (close_sbuf() < 0)
551 			return ERR;
552 		else if (open_sbuf() < 0)
553 			return FATAL;
554 		if (*fnp && *fnp != '!')
555 			strlcpy(old_filename, fnp, sizeof old_filename);
556 #ifdef BACKWARDS
557 		if (*fnp == '\0' && *old_filename == '\0') {
558 			seterrmsg("no current filename");
559 			return ERR;
560 		}
561 #endif
562 		if (read_file(*fnp ? fnp : old_filename, 0) < 0)
563 			return ERR;
564 		clear_undo_stack();
565 		modified = 0;
566 		u_current_addr = u_addr_last = -1;
567 		break;
568 	case 'f':
569 		if (addr_cnt > 0) {
570 			seterrmsg("unexpected address");
571 			return ERR;
572 		} else if (!isspace(*ibufp)) {
573 			seterrmsg("unexpected command suffix");
574 			return ERR;
575 		} else if ((fnp = get_filename()) == NULL)
576 			return ERR;
577 		else if (*fnp == '!') {
578 			seterrmsg("invalid redirection");
579 			return ERR;
580 		}
581 		GET_COMMAND_SUFFIX();
582 		if (*fnp)
583 			strlcpy(old_filename, fnp, sizeof old_filename);
584 		puts(strip_escapes(old_filename));
585 		break;
586 	case 'g':
587 	case 'v':
588 	case 'G':
589 	case 'V':
590 		if (isglobal) {
591 			seterrmsg("cannot nest global commands");
592 			return ERR;
593 		} else if (check_addr_range(1, addr_last) < 0)
594 			return ERR;
595 		else if (build_active_list(c == 'g' || c == 'G') < 0)
596 			return ERR;
597 		else if ((n = (c == 'G' || c == 'V')))
598 			GET_COMMAND_SUFFIX();
599 		isglobal++;
600 		if (exec_global(n, gflag) < 0)
601 			return ERR;
602 		break;
603 	case 'h':
604 		if (addr_cnt > 0) {
605 			seterrmsg("unexpected address");
606 			return ERR;
607 		}
608 		GET_COMMAND_SUFFIX();
609 		if (*errmsg) fprintf(stderr, "%s\n", errmsg);
610 		break;
611 	case 'H':
612 		if (addr_cnt > 0) {
613 			seterrmsg("unexpected address");
614 			return ERR;
615 		}
616 		GET_COMMAND_SUFFIX();
617 		if ((garrulous = 1 - garrulous) && *errmsg)
618 			fprintf(stderr, "%s\n", errmsg);
619 		break;
620 	case 'i':
621 		if (second_addr == 0) {
622 			seterrmsg("invalid address");
623 			return ERR;
624 		}
625 		GET_COMMAND_SUFFIX();
626 		if (!isglobal) clear_undo_stack();
627 		if (append_lines(second_addr - 1) < 0)
628 			return ERR;
629 		break;
630 	case 'j':
631 		if (check_addr_range(current_addr, current_addr + 1) < 0)
632 			return ERR;
633 		GET_COMMAND_SUFFIX();
634 		if (!isglobal) clear_undo_stack();
635 		if (first_addr != second_addr &&
636 		    join_lines(first_addr, second_addr) < 0)
637 			return ERR;
638 		break;
639 	case 'k':
640 		c = *ibufp++;
641 		if (second_addr == 0) {
642 			seterrmsg("invalid address");
643 			return ERR;
644 		}
645 		GET_COMMAND_SUFFIX();
646 		if (mark_line_node(get_addressed_line_node(second_addr), c) < 0)
647 			return ERR;
648 		break;
649 	case 'l':
650 		if (check_addr_range(current_addr, current_addr) < 0)
651 			return ERR;
652 		GET_COMMAND_SUFFIX();
653 		if (display_lines(first_addr, second_addr, gflag | GLS) < 0)
654 			return ERR;
655 		gflag = 0;
656 		break;
657 	case 'm':
658 		if (check_addr_range(current_addr, current_addr) < 0)
659 			return ERR;
660 		GET_THIRD_ADDR(addr);
661 		if (first_addr <= addr && addr < second_addr) {
662 			seterrmsg("invalid destination");
663 			return ERR;
664 		}
665 		GET_COMMAND_SUFFIX();
666 		if (!isglobal) clear_undo_stack();
667 		if (move_lines(addr) < 0)
668 			return ERR;
669 		break;
670 	case 'n':
671 		if (check_addr_range(current_addr, current_addr) < 0)
672 			return ERR;
673 		GET_COMMAND_SUFFIX();
674 		if (display_lines(first_addr, second_addr, gflag | GNP) < 0)
675 			return ERR;
676 		gflag = 0;
677 		break;
678 	case 'p':
679 		if (check_addr_range(current_addr, current_addr) < 0)
680 			return ERR;
681 		GET_COMMAND_SUFFIX();
682 		if (display_lines(first_addr, second_addr, gflag | GPR) < 0)
683 			return ERR;
684 		gflag = 0;
685 		break;
686 	case 'P':
687 		if (addr_cnt > 0) {
688 			seterrmsg("unexpected address");
689 			return ERR;
690 		}
691 		GET_COMMAND_SUFFIX();
692 		prompt = prompt ? NULL : optarg ? optarg : dps;
693 		break;
694 	case 'q':
695 	case 'Q':
696 		if (addr_cnt > 0) {
697 			seterrmsg("unexpected address");
698 			return ERR;
699 		}
700 		GET_COMMAND_SUFFIX();
701 		gflag =  (modified && !scripted && c == 'q') ? EMOD : EOF;
702 		break;
703 	case 'r':
704 		if (!isspace(*ibufp)) {
705 			seterrmsg("unexpected command suffix");
706 			return ERR;
707 		} else if (addr_cnt == 0)
708 			second_addr = addr_last;
709 		if ((fnp = get_filename()) == NULL)
710 			return ERR;
711 		GET_COMMAND_SUFFIX();
712 		if (!isglobal) clear_undo_stack();
713 		if (*old_filename == '\0' && *fnp != '!')
714 			strlcpy(old_filename, fnp, sizeof old_filename);
715 #ifdef BACKWARDS
716 		if (*fnp == '\0' && *old_filename == '\0') {
717 			seterrmsg("no current filename");
718 			return ERR;
719 		}
720 #endif
721 		if ((addr = read_file(*fnp ? fnp : old_filename,
722 		    second_addr)) < 0)
723 			return ERR;
724 		else if (addr && addr != addr_last)
725 			modified = 1;
726 		break;
727 	case 's':
728 		do {
729 			switch (*ibufp) {
730 			case '\n':
731 				sflags |=SGF;
732 				break;
733 			case 'g':
734 				sflags |= SGG;
735 				ibufp++;
736 				break;
737 			case 'p':
738 				sflags |= SGP;
739 				ibufp++;
740 				break;
741 			case 'r':
742 				sflags |= SGR;
743 				ibufp++;
744 				break;
745 			case '0': case '1': case '2': case '3': case '4':
746 			case '5': case '6': case '7': case '8': case '9':
747 				STRTOI(sgnum, ibufp);
748 				sflags |= SGF;
749 				sgflag &= ~GSG;		/* override GSG */
750 				break;
751 			default:
752 				if (sflags) {
753 					seterrmsg("invalid command suffix");
754 					return ERR;
755 				}
756 			}
757 		} while (sflags && *ibufp != '\n');
758 		if (sflags && !pat) {
759 			seterrmsg("no previous substitution");
760 			return ERR;
761 		} else if (sflags & SGG)
762 			sgnum = 0;		/* override numeric arg */
763 		if (*ibufp != '\n' && *(ibufp + 1) == '\n') {
764 			seterrmsg("invalid pattern delimiter");
765 			return ERR;
766 		}
767 		tpat = pat;
768 		SPL1();
769 		if ((!sflags || (sflags & SGR)) &&
770 		    (tpat = get_compiled_pattern()) == NULL) {
771 		 	SPL0();
772 			return ERR;
773 		} else if (tpat != pat) {
774 			if (pat) {
775 				regfree(pat);
776 				free(pat);
777 			}
778 			pat = tpat;
779 			patlock = 1;		/* reserve pattern */
780 		}
781 		SPL0();
782 		if (!sflags && extract_subst_tail(&sgflag, &sgnum) < 0)
783 			return ERR;
784 		else if (isglobal)
785 			sgflag |= GLB;
786 		else
787 			sgflag &= ~GLB;
788 		if (sflags & SGG)
789 			sgflag ^= GSG;
790 		if (sflags & SGP) {
791 			sgflag ^= GPR;
792 			sgflag &= ~(GLS | GNP);
793 		}
794 		do {
795 			switch (*ibufp) {
796 			case 'p':
797 				sgflag |= GPR;
798 				ibufp++;
799 				break;
800 			case 'l':
801 				sgflag |= GLS;
802 				ibufp++;
803 				break;
804 			case 'n':
805 				sgflag |= GNP;
806 				ibufp++;
807 				break;
808 			default:
809 				n++;
810 			}
811 		} while (!n);
812 		if (check_addr_range(current_addr, current_addr) < 0)
813 			return ERR;
814 		GET_COMMAND_SUFFIX();
815 		if (!isglobal) clear_undo_stack();
816 		if (search_and_replace(pat, sgflag, sgnum) < 0)
817 			return ERR;
818 		break;
819 	case 't':
820 		if (check_addr_range(current_addr, current_addr) < 0)
821 			return ERR;
822 		GET_THIRD_ADDR(addr);
823 		GET_COMMAND_SUFFIX();
824 		if (!isglobal) clear_undo_stack();
825 		if (copy_lines(addr) < 0)
826 			return ERR;
827 		break;
828 	case 'u':
829 		if (addr_cnt > 0) {
830 			seterrmsg("unexpected address");
831 			return ERR;
832 		}
833 		GET_COMMAND_SUFFIX();
834 		if (pop_undo_stack() < 0)
835 			return ERR;
836 		break;
837 	case 'w':
838 	case 'W':
839 		if ((n = *ibufp) == 'q' || n == 'Q') {
840 			gflag = EOF;
841 			ibufp++;
842 		}
843 		if (!isspace(*ibufp)) {
844 			seterrmsg("unexpected command suffix");
845 			return ERR;
846 		} else if ((fnp = get_filename()) == NULL)
847 			return ERR;
848 		if (addr_cnt == 0 && !addr_last)
849 			first_addr = second_addr = 0;
850 		else if (check_addr_range(1, addr_last) < 0)
851 			return ERR;
852 		GET_COMMAND_SUFFIX();
853 		if (*old_filename == '\0' && *fnp != '!')
854 			strlcpy(old_filename, fnp, sizeof old_filename);
855 #ifdef BACKWARDS
856 		if (*fnp == '\0' && *old_filename == '\0') {
857 			seterrmsg("no current filename");
858 			return ERR;
859 		}
860 #endif
861 		if ((addr = write_file(*fnp ? fnp : old_filename,
862 		    (c == 'W') ? "a" : "w", first_addr, second_addr)) < 0)
863 			return ERR;
864 		else if (addr == addr_last)
865 			modified = 0;
866 		else if (modified && !scripted && n == 'q')
867 			gflag = EMOD;
868 		break;
869 	case 'x':
870 		if (addr_cnt > 0) {
871 			seterrmsg("unexpected address");
872 			return ERR;
873 		}
874 		GET_COMMAND_SUFFIX();
875 #ifdef DES
876 		des = get_keyword();
877 #else
878 		seterrmsg("crypt unavailable");
879 		return ERR;
880 #endif
881 		break;
882 	case 'z':
883 		first_addr = 1;
884 #ifdef BACKWARDS
885 		if (check_addr_range(first_addr, current_addr + 1) < 0)
886 #else
887 		if (check_addr_range(first_addr, current_addr + !isglobal) < 0)
888 #endif
889 			return ERR;
890 		else if ('0' < *ibufp && *ibufp <= '9')
891 			STRTOI(rows, ibufp);
892 		GET_COMMAND_SUFFIX();
893 		if (display_lines(second_addr, min(addr_last,
894 		    second_addr + rows), gflag) < 0)
895 			return ERR;
896 		gflag = 0;
897 		break;
898 	case '=':
899 		GET_COMMAND_SUFFIX();
900 		printf("%d\n", addr_cnt ? second_addr : addr_last);
901 		break;
902 	case '!':
903 		if (addr_cnt > 0) {
904 			seterrmsg("unexpected address");
905 			return ERR;
906 		} else if ((sflags = get_shell_command()) < 0)
907 			return ERR;
908 		GET_COMMAND_SUFFIX();
909 		if (sflags) printf("%s\n", shcmd + 1);
910 		system(shcmd + 1);
911 		if (!scripted) printf("!\n");
912 		break;
913 	case '\n':
914 		first_addr = 1;
915 #ifdef BACKWARDS
916 		if (check_addr_range(first_addr, current_addr + 1) < 0
917 #else
918 		if (check_addr_range(first_addr, current_addr + !isglobal) < 0
919 #endif
920 		 || display_lines(second_addr, second_addr, 0) < 0)
921 			return ERR;
922 		break;
923 	default:
924 		seterrmsg("unknown command");
925 		return ERR;
926 	}
927 	return gflag;
928 }
929 
930 
931 /* check_addr_range: return status of address range check */
932 int
933 check_addr_range(int n, int m)
934 {
935 	if (addr_cnt == 0) {
936 		first_addr = n;
937 		second_addr = m;
938 	}
939 	if (first_addr > second_addr || 1 > first_addr ||
940 	    second_addr > addr_last) {
941 		seterrmsg("invalid address");
942 		return ERR;
943 	}
944 	return 0;
945 }
946 
947 
948 /* get_matching_node_addr: return the address of the next line matching a
949    pattern in a given direction.  wrap around begin/end of editor buffer if
950    necessary */
951 int
952 get_matching_node_addr(pattern_t *pat, int dir)
953 {
954 	char *s;
955 	int n = current_addr;
956 	line_t *lp;
957 
958 	if (!pat) return ERR;
959 	do {
960 		if ((n = dir ? INC_MOD(n, addr_last) : DEC_MOD(n, addr_last))) {
961 			lp = get_addressed_line_node(n);
962 			if ((s = get_sbuf_line(lp)) == NULL)
963 				return ERR;
964 			if (isbinary)
965 				NUL_TO_NEWLINE(s, lp->len);
966 			if (!regexec(pat, s, 0, NULL, 0))
967 				return n;
968 		}
969 	} while (n != current_addr);
970 	seterrmsg("no match");
971 	return  ERR;
972 }
973 
974 
975 /* get_filename: return pointer to copy of filename in the command buffer */
976 char *
977 get_filename(void)
978 {
979 	static char *file = NULL;
980 	static int filesz = 0;
981 	int n;
982 
983 	if (*ibufp != '\n') {
984 		SKIP_BLANKS();
985 		if (*ibufp == '\n') {
986 			seterrmsg("invalid filename");
987 			return NULL;
988 		} else if ((ibufp = get_extended_line(&n, 1)) == NULL)
989 			return NULL;
990 		else if (*ibufp == '!') {
991 			ibufp++;
992 			if ((n = get_shell_command()) < 0)
993 				return NULL;
994 			if (n) printf("%s\n", shcmd + 1);
995 			return shcmd;
996 		} else if (n >= MAXPATHLEN) {
997 			seterrmsg("filename too long");
998 			return  NULL;
999 		}
1000 	}
1001 #ifndef BACKWARDS
1002 	else if (*old_filename == '\0') {
1003 		seterrmsg("no current filename");
1004 		return  NULL;
1005 	}
1006 #endif
1007 	REALLOC(file, filesz, MAXPATHLEN, NULL);
1008 	for (n = 0; *ibufp != '\n';)
1009 		file[n++] = *ibufp++;
1010 	file[n] = '\0';
1011 	return is_legal_filename(file) ? file : NULL;
1012 }
1013 
1014 
1015 /* get_shell_command: read a shell command from stdin; return substitution
1016    status */
1017 int
1018 get_shell_command(void)
1019 {
1020 	static char *buf = NULL;
1021 	static int n = 0;
1022 
1023 	char *s;			/* substitution char pointer */
1024 	int i = 0;
1025 	int j = 0;
1026 
1027 	if (red) {
1028 		seterrmsg("shell access restricted");
1029 		return ERR;
1030 	} else if ((s = ibufp = get_extended_line(&j, 1)) == NULL)
1031 		return ERR;
1032 	REALLOC(buf, n, j + 1, ERR);
1033 	buf[i++] = '!';			/* prefix command w/ bang */
1034 	while (*ibufp != '\n')
1035 		switch (*ibufp) {
1036 		default:
1037 			REALLOC(buf, n, i + 2, ERR);
1038 			buf[i++] = *ibufp;
1039 			if (*ibufp++ == '\\')
1040 				buf[i++] = *ibufp++;
1041 			break;
1042 		case '!':
1043 			if (s != ibufp) {
1044 				REALLOC(buf, n, i + 1, ERR);
1045 				buf[i++] = *ibufp++;
1046 			}
1047 #ifdef BACKWARDS
1048 			else if (shcmd == NULL || *(shcmd + 1) == '\0')
1049 #else
1050 			else if (shcmd == NULL)
1051 #endif
1052 			{
1053 				seterrmsg("no previous command");
1054 				return ERR;
1055 			} else {
1056 				REALLOC(buf, n, i + shcmdi, ERR);
1057 				for (s = shcmd + 1; s < shcmd + shcmdi;)
1058 					buf[i++] = *s++;
1059 				s = ibufp++;
1060 			}
1061 			break;
1062 		case '%':
1063 			if (*old_filename  == '\0') {
1064 				seterrmsg("no current filename");
1065 				return ERR;
1066 			}
1067 			j = strlen(s = strip_escapes(old_filename));
1068 			REALLOC(buf, n, i + j, ERR);
1069 			while (j--)
1070 				buf[i++] = *s++;
1071 			s = ibufp++;
1072 			break;
1073 		}
1074 	REALLOC(shcmd, shcmdsz, i + 1, ERR);
1075 	memcpy(shcmd, buf, i);
1076 	shcmd[shcmdi = i] = '\0';
1077 	return *s == '!' || *s == '%';
1078 }
1079 
1080 
1081 /* append_lines: insert text from stdin to after line n; stop when either a
1082    single period is read or EOF; return status */
1083 int
1084 append_lines(int n)
1085 {
1086 	int l;
1087 	char *lp = ibuf;
1088 	char *eot;
1089 	undo_t *up = NULL;
1090 
1091 	for (current_addr = n;;) {
1092 		if (!isglobal) {
1093 			if ((l = get_tty_line()) < 0)
1094 				return ERR;
1095 			else if (l == 0 || ibuf[l - 1] != '\n') {
1096 				clearerr(stdin);
1097 				return  l ? EOF : 0;
1098 			}
1099 			lp = ibuf;
1100 		} else if (*(lp = ibufp) == '\0')
1101 			return 0;
1102 		else {
1103 			while (*ibufp++ != '\n')
1104 				;
1105 			l = ibufp - lp;
1106 		}
1107 		if (l == 2 && lp[0] == '.' && lp[1] == '\n') {
1108 			return 0;
1109 		}
1110 		eot = lp + l;
1111 		SPL1();
1112 		do {
1113 			if ((lp = put_sbuf_line(lp)) == NULL) {
1114 				SPL0();
1115 				return ERR;
1116 			} else if (up)
1117 				up->t = get_addressed_line_node(current_addr);
1118 			else if ((up = push_undo_stack(UADD, current_addr,
1119 			    current_addr)) == NULL) {
1120 				SPL0();
1121 				return ERR;
1122 			}
1123 		} while (lp != eot);
1124 		modified = 1;
1125 		SPL0();
1126 	}
1127 	/* NOTREACHED */
1128 }
1129 
1130 
1131 /* join_lines: replace a range of lines with the joined text of those lines */
1132 int
1133 join_lines(int from, int to)
1134 {
1135 	static char *buf = NULL;
1136 	static int n;
1137 
1138 	char *s;
1139 	int size = 0;
1140 	line_t *bp, *ep;
1141 
1142 	ep = get_addressed_line_node(INC_MOD(to, addr_last));
1143 	bp = get_addressed_line_node(from);
1144 	for (; bp != ep; bp = bp->q_forw) {
1145 		if ((s = get_sbuf_line(bp)) == NULL)
1146 			return ERR;
1147 		REALLOC(buf, n, size + bp->len, ERR);
1148 		memcpy(buf + size, s, bp->len);
1149 		size += bp->len;
1150 	}
1151 	REALLOC(buf, n, size + 2, ERR);
1152 	memcpy(buf + size, "\n", 2);
1153 	if (delete_lines(from, to) < 0)
1154 		return ERR;
1155 	current_addr = from - 1;
1156 	SPL1();
1157 	if (put_sbuf_line(buf) == NULL ||
1158 	    push_undo_stack(UADD, current_addr, current_addr) == NULL) {
1159 		SPL0();
1160 		return ERR;
1161 	}
1162 	modified = 1;
1163 	SPL0();
1164 	return 0;
1165 }
1166 
1167 
1168 /* move_lines: move a range of lines */
1169 int
1170 move_lines(int addr)
1171 {
1172 	line_t *b1, *a1, *b2, *a2;
1173 	int n = INC_MOD(second_addr, addr_last);
1174 	int p = first_addr - 1;
1175 	int done = (addr == first_addr - 1 || addr == second_addr);
1176 
1177 	SPL1();
1178 	if (done) {
1179 		a2 = get_addressed_line_node(n);
1180 		b2 = get_addressed_line_node(p);
1181 		current_addr = second_addr;
1182 	} else if (push_undo_stack(UMOV, p, n) == NULL ||
1183 	    push_undo_stack(UMOV, addr, INC_MOD(addr, addr_last)) == NULL) {
1184 		SPL0();
1185 		return ERR;
1186 	} else {
1187 		a1 = get_addressed_line_node(n);
1188 		if (addr < first_addr) {
1189 			b1 = get_addressed_line_node(p);
1190 			b2 = get_addressed_line_node(addr);
1191 					/* this get_addressed_line_node last! */
1192 		} else {
1193 			b2 = get_addressed_line_node(addr);
1194 			b1 = get_addressed_line_node(p);
1195 					/* this get_addressed_line_node last! */
1196 		}
1197 		a2 = b2->q_forw;
1198 		REQUE(b2, b1->q_forw);
1199 		REQUE(a1->q_back, a2);
1200 		REQUE(b1, a1);
1201 		current_addr = addr + ((addr < first_addr) ?
1202 		    second_addr - first_addr + 1 : 0);
1203 	}
1204 	if (isglobal)
1205 		unset_active_nodes(b2->q_forw, a2);
1206 	modified = 1;
1207 	SPL0();
1208 	return 0;
1209 }
1210 
1211 
1212 /* copy_lines: copy a range of lines; return status */
1213 int
1214 copy_lines(int addr)
1215 {
1216 	line_t *lp, *np = get_addressed_line_node(first_addr);
1217 	undo_t *up = NULL;
1218 	int n = second_addr - first_addr + 1;
1219 	int m = 0;
1220 
1221 	current_addr = addr;
1222 	if (first_addr <= addr && addr < second_addr) {
1223 		n =  addr - first_addr + 1;
1224 		m = second_addr - addr;
1225 	}
1226 	for (; n > 0; n=m, m=0, np = get_addressed_line_node(current_addr + 1))
1227 		for (; n-- > 0; np = np->q_forw) {
1228 			SPL1();
1229 			if ((lp = dup_line_node(np)) == NULL) {
1230 				SPL0();
1231 				return ERR;
1232 			}
1233 			add_line_node(lp);
1234 			if (up)
1235 				up->t = lp;
1236 			else if ((up = push_undo_stack(UADD, current_addr,
1237 			    current_addr)) == NULL) {
1238 				SPL0();
1239 				return ERR;
1240 			}
1241 			modified = 1;
1242 			SPL0();
1243 		}
1244 	return 0;
1245 }
1246 
1247 
1248 /* delete_lines: delete a range of lines */
1249 int
1250 delete_lines(int from, int to)
1251 {
1252 	line_t *n, *p;
1253 
1254 	SPL1();
1255 	if (push_undo_stack(UDEL, from, to) == NULL) {
1256 		SPL0();
1257 		return ERR;
1258 	}
1259 	n = get_addressed_line_node(INC_MOD(to, addr_last));
1260 	p = get_addressed_line_node(from - 1);
1261 					/* this get_addressed_line_node last! */
1262 	if (isglobal)
1263 		unset_active_nodes(p->q_forw, n);
1264 	REQUE(p, n);
1265 	addr_last -= to - from + 1;
1266 	current_addr = from - 1;
1267 	modified = 1;
1268 	SPL0();
1269 	return 0;
1270 }
1271 
1272 
1273 /* display_lines: print a range of lines to stdout */
1274 int
1275 display_lines(int from, int to, int gflag)
1276 {
1277 	line_t *bp;
1278 	line_t *ep;
1279 	char *s;
1280 
1281 	if (!from) {
1282 		seterrmsg("invalid address");
1283 		return ERR;
1284 	}
1285 	ep = get_addressed_line_node(INC_MOD(to, addr_last));
1286 	bp = get_addressed_line_node(from);
1287 	for (; bp != ep; bp = bp->q_forw) {
1288 		if ((s = get_sbuf_line(bp)) == NULL)
1289 			return ERR;
1290 		if (put_tty_line(s, bp->len, current_addr = from++, gflag) < 0)
1291 			return ERR;
1292 	}
1293 	return 0;
1294 }
1295 
1296 
1297 #define MAXMARK 26			/* max number of marks */
1298 
1299 line_t	*mark[MAXMARK];			/* line markers */
1300 int markno;				/* line marker count */
1301 
1302 /* mark_line_node: set a line node mark */
1303 int
1304 mark_line_node(line_t *lp, int n)
1305 {
1306 	if (!islower(n)) {
1307 		seterrmsg("invalid mark character");
1308 		return ERR;
1309 	} else if (mark[n - 'a'] == NULL)
1310 		markno++;
1311 	mark[n - 'a'] = lp;
1312 	return 0;
1313 }
1314 
1315 
1316 /* get_marked_node_addr: return address of a marked line */
1317 int
1318 get_marked_node_addr(int n)
1319 {
1320 	if (!islower(n)) {
1321 		seterrmsg("invalid mark character");
1322 		return ERR;
1323 	}
1324 	return get_line_node_addr(mark[n - 'a']);
1325 }
1326 
1327 
1328 /* unmark_line_node: clear line node mark */
1329 void
1330 unmark_line_node(line_t *lp)
1331 {
1332 	int i;
1333 
1334 	for (i = 0; markno && i < MAXMARK; i++)
1335 		if (mark[i] == lp) {
1336 			mark[i] = NULL;
1337 			markno--;
1338 		}
1339 }
1340 
1341 
1342 /* dup_line_node: return a pointer to a copy of a line node */
1343 line_t *
1344 dup_line_node(line_t *lp)
1345 {
1346 	line_t *np;
1347 
1348 	if ((np = (line_t *) malloc(sizeof(line_t))) == NULL) {
1349 		perror(NULL);
1350 		seterrmsg("out of memory");
1351 		return NULL;
1352 	}
1353 	np->seek = lp->seek;
1354 	np->len = lp->len;
1355 	return np;
1356 }
1357 
1358 
1359 /* has_trailing_escape:  return the parity of escapes preceding a character
1360    in a string */
1361 int
1362 has_trailing_escape(char *s, char *t)
1363 {
1364     return (s == t || *(t - 1) != '\\') ? 0 : !has_trailing_escape(s, t - 1);
1365 }
1366 
1367 
1368 /* strip_escapes: return copy of escaped string of at most length MAXPATHLEN */
1369 char *
1370 strip_escapes(char *s)
1371 {
1372 	static char *file = NULL;
1373 	static int filesz = 0;
1374 
1375 	int i = 0;
1376 
1377 	REALLOC(file, filesz, MAXPATHLEN, NULL);
1378 	/* assert: no trailing escape */
1379 	while ((file[i++] = (*s == '\\') ? *++s : *s) != '\0' &&
1380 	       i < MAXPATHLEN-1)
1381 		s++;
1382 	file[MAXPATHLEN-1] = '\0';
1383 	return file;
1384 }
1385 
1386 
1387 void
1388 signal_hup(int signo)
1389 {
1390 	int save_errno = errno;
1391 
1392 	if (mutex)
1393 		sigflags |= (1 << (signo - 1));
1394 	else
1395 		handle_hup(signo);
1396 	errno = save_errno;
1397 }
1398 
1399 
1400 void
1401 signal_int(int signo)
1402 {
1403 	int save_errno = errno;
1404 
1405 	if (mutex)
1406 		sigflags |= (1 << (signo - 1));
1407 	else
1408 		handle_int(signo);
1409 	errno = save_errno;
1410 }
1411 
1412 
1413 void
1414 handle_hup(int signo)
1415 {
1416 	char hup[MAXPATHLEN];
1417 
1418 	if (!sigactive)
1419 		quit(1);
1420 	sigflags &= ~(1 << (signo - 1));
1421 	/* XXX signal race */
1422 	if (addr_last && write_file("ed.hup", "w", 1, addr_last) < 0 &&
1423 	    home != NULL && home[0] == '/') {
1424 		if (strlcpy(hup, home, sizeof(hup)) < sizeof(hup) &&
1425 		    strlcat(hup, "/ed.hup", sizeof(hup)) < sizeof(hup))
1426 			write_file(hup, "w", 1, addr_last);
1427 	}
1428 	_exit(2);
1429 }
1430 
1431 
1432 void
1433 handle_int(int signo)
1434 {
1435 	if (!sigactive)
1436 		_exit(1);
1437 	sigflags &= ~(1 << (signo - 1));
1438 #ifdef _POSIX_SOURCE
1439 	siglongjmp(env, -1);
1440 #else
1441 	longjmp(env, -1);
1442 #endif
1443 }
1444 
1445 
1446 void
1447 handle_winch(int signo)
1448 {
1449 	int save_errno = errno;
1450 	struct winsize ws;		/* window size structure */
1451 
1452 	sigflags &= ~(1 << (signo - 1));
1453 	if (ioctl(0, TIOCGWINSZ, &ws) >= 0) {
1454 		if (ws.ws_row > 2)
1455 			rows = ws.ws_row - 2;
1456 		if (ws.ws_col > 8)
1457 			cols = ws.ws_col - 8;
1458 	}
1459 	errno = save_errno;
1460 }
1461 
1462 
1463 /* is_legal_filename: return a legal filename */
1464 int
1465 is_legal_filename(char *s)
1466 {
1467 	if (red && (*s == '!' || !strcmp(s, "..") || strchr(s, '/'))) {
1468 		seterrmsg("shell access restricted");
1469 		return 0;
1470 	}
1471 	return 1;
1472 }
1473