xref: /openbsd/bin/ksh/c_sh.c (revision 9ab2d3bb)
1 /*	$OpenBSD: c_sh.c,v 1.65 2023/09/14 18:32:03 cheloha Exp $	*/
2 
3 /*
4  * built-in Bourne commands
5  */
6 
7 #include <sys/resource.h>
8 #include <sys/stat.h>
9 #include <sys/time.h>
10 
11 #include <ctype.h>
12 #include <errno.h>
13 #include <fcntl.h>
14 #include <stdio.h>
15 #include <stdlib.h>
16 #include <string.h>
17 #include <unistd.h>
18 
19 #include "sh.h"
20 
21 static void p_tv(struct shf *, int, struct timeval *, int, char *, char *);
22 static void p_ts(struct shf *, int, struct timespec *, int, char *, char *);
23 
24 /* :, false and true */
25 int
c_label(char ** wp)26 c_label(char **wp)
27 {
28 	return wp[0][0] == 'f' ? 1 : 0;
29 }
30 
31 int
c_shift(char ** wp)32 c_shift(char **wp)
33 {
34 	struct block *l = genv->loc;
35 	int n;
36 	int64_t val;
37 	char *arg;
38 
39 	if (ksh_getopt(wp, &builtin_opt, null) == '?')
40 		return 1;
41 	arg = wp[builtin_opt.optind];
42 
43 	if (arg) {
44 		evaluate(arg, &val, KSH_UNWIND_ERROR, false);
45 		n = val;
46 	} else
47 		n = 1;
48 	if (n < 0) {
49 		bi_errorf("%s: bad number", arg);
50 		return (1);
51 	}
52 	if (l->argc < n) {
53 		bi_errorf("nothing to shift");
54 		return (1);
55 	}
56 	l->argv[n] = l->argv[0];
57 	l->argv += n;
58 	l->argc -= n;
59 	return 0;
60 }
61 
62 int
c_umask(char ** wp)63 c_umask(char **wp)
64 {
65 	int i;
66 	char *cp;
67 	int symbolic = 0;
68 	mode_t old_umask;
69 	int optc;
70 
71 	while ((optc = ksh_getopt(wp, &builtin_opt, "S")) != -1)
72 		switch (optc) {
73 		case 'S':
74 			symbolic = 1;
75 			break;
76 		case '?':
77 			return 1;
78 		}
79 	cp = wp[builtin_opt.optind];
80 	if (cp == NULL) {
81 		old_umask = umask(0);
82 		umask(old_umask);
83 		if (symbolic) {
84 			char buf[18];
85 			int j;
86 
87 			old_umask = ~old_umask;
88 			cp = buf;
89 			for (i = 0; i < 3; i++) {
90 				*cp++ = "ugo"[i];
91 				*cp++ = '=';
92 				for (j = 0; j < 3; j++)
93 					if (old_umask & (1 << (8 - (3*i + j))))
94 						*cp++ = "rwx"[j];
95 				*cp++ = ',';
96 			}
97 			cp[-1] = '\0';
98 			shprintf("%s\n", buf);
99 		} else
100 			shprintf("%#3.3o\n", old_umask);
101 	} else {
102 		mode_t new_umask;
103 
104 		if (digit(*cp)) {
105 			for (new_umask = 0; *cp >= '0' && *cp <= '7'; cp++)
106 				new_umask = new_umask * 8 + (*cp - '0');
107 			if (*cp) {
108 				bi_errorf("bad number");
109 				return 1;
110 			}
111 		} else {
112 			/* symbolic format */
113 			int positions, new_val;
114 			char op;
115 
116 			old_umask = umask(0);
117 			umask(old_umask); /* in case of error */
118 			old_umask = ~old_umask;
119 			new_umask = old_umask;
120 			positions = 0;
121 			while (*cp) {
122 				while (*cp && strchr("augo", *cp))
123 					switch (*cp++) {
124 					case 'a':
125 						positions |= 0111;
126 						break;
127 					case 'u':
128 						positions |= 0100;
129 						break;
130 					case 'g':
131 						positions |= 0010;
132 						break;
133 					case 'o':
134 						positions |= 0001;
135 						break;
136 					}
137 				if (!positions)
138 					positions = 0111; /* default is a */
139 				if (!strchr("=+-", op = *cp))
140 					break;
141 				cp++;
142 				new_val = 0;
143 				while (*cp && strchr("rwxugoXs", *cp))
144 					switch (*cp++) {
145 					case 'r': new_val |= 04; break;
146 					case 'w': new_val |= 02; break;
147 					case 'x': new_val |= 01; break;
148 					case 'u': new_val |= old_umask >> 6;
149 						  break;
150 					case 'g': new_val |= old_umask >> 3;
151 						  break;
152 					case 'o': new_val |= old_umask >> 0;
153 						  break;
154 					case 'X': if (old_umask & 0111)
155 							new_val |= 01;
156 						  break;
157 					case 's': /* ignored */
158 						  break;
159 					}
160 				new_val = (new_val & 07) * positions;
161 				switch (op) {
162 				case '-':
163 					new_umask &= ~new_val;
164 					break;
165 				case '=':
166 					new_umask = new_val |
167 					    (new_umask & ~(positions * 07));
168 					break;
169 				case '+':
170 					new_umask |= new_val;
171 				}
172 				if (*cp == ',') {
173 					positions = 0;
174 					cp++;
175 				} else if (!strchr("=+-", *cp))
176 					break;
177 			}
178 			if (*cp) {
179 				bi_errorf("bad mask");
180 				return 1;
181 			}
182 			new_umask = ~new_umask;
183 		}
184 		umask(new_umask);
185 	}
186 	return 0;
187 }
188 
189 int
c_dot(char ** wp)190 c_dot(char **wp)
191 {
192 	char *file, *cp;
193 	char **argv;
194 	int argc;
195 	int i;
196 	int err;
197 
198 	if (ksh_getopt(wp, &builtin_opt, null) == '?')
199 		return 1;
200 
201 	if ((cp = wp[builtin_opt.optind]) == NULL)
202 		return 0;
203 	file = search(cp, search_path, R_OK, &err);
204 	if (file == NULL) {
205 		bi_errorf("%s: %s", cp, err ? strerror(err) : "not found");
206 		return 1;
207 	}
208 
209 	/* Set positional parameters? */
210 	if (wp[builtin_opt.optind + 1]) {
211 		argv = wp + builtin_opt.optind;
212 		argv[0] = genv->loc->argv[0]; /* preserve $0 */
213 		for (argc = 0; argv[argc + 1]; argc++)
214 			;
215 	} else {
216 		argc = 0;
217 		argv = NULL;
218 	}
219 	i = include(file, argc, argv, 0);
220 	if (i < 0) { /* should not happen */
221 		bi_errorf("%s: %s", cp, strerror(errno));
222 		return 1;
223 	}
224 	return i;
225 }
226 
227 int
c_wait(char ** wp)228 c_wait(char **wp)
229 {
230 	int rv = 0;
231 	int sig;
232 
233 	if (ksh_getopt(wp, &builtin_opt, null) == '?')
234 		return 1;
235 	wp += builtin_opt.optind;
236 	if (*wp == NULL) {
237 		while (waitfor(NULL, &sig) >= 0)
238 			;
239 		rv = sig;
240 	} else {
241 		for (; *wp; wp++)
242 			rv = waitfor(*wp, &sig);
243 		if (rv < 0)
244 			rv = sig ? sig : 127; /* magic exit code: bad job-id */
245 	}
246 	return rv;
247 }
248 
249 int
c_read(char ** wp)250 c_read(char **wp)
251 {
252 	int c = 0;
253 	int expand = 1, savehist = 0;
254 	int expanding;
255 	int ecode = 0;
256 	char *cp;
257 	int fd = 0;
258 	struct shf *shf;
259 	int optc;
260 	const char *emsg;
261 	XString cs, xs;
262 	struct tbl *vp;
263 	char *xp = NULL;
264 
265 	while ((optc = ksh_getopt(wp, &builtin_opt, "prsu,")) != -1)
266 		switch (optc) {
267 		case 'p':
268 			if ((fd = coproc_getfd(R_OK, &emsg)) < 0) {
269 				bi_errorf("-p: %s", emsg);
270 				return 1;
271 			}
272 			break;
273 		case 'r':
274 			expand = 0;
275 			break;
276 		case 's':
277 			savehist = 1;
278 			break;
279 		case 'u':
280 			if (!*(cp = builtin_opt.optarg))
281 				fd = 0;
282 			else if ((fd = check_fd(cp, R_OK, &emsg)) < 0) {
283 				bi_errorf("-u: %s: %s", cp, emsg);
284 				return 1;
285 			}
286 			break;
287 		case '?':
288 			return 1;
289 		}
290 	wp += builtin_opt.optind;
291 
292 	if (*wp == NULL)
293 		*--wp = "REPLY";
294 
295 	/* Since we can't necessarily seek backwards on non-regular files,
296 	 * don't buffer them so we can't read too much.
297 	 */
298 	shf = shf_reopen(fd, SHF_RD | SHF_INTERRUPT | can_seek(fd), shl_spare);
299 
300 	if ((cp = strchr(*wp, '?')) != NULL) {
301 		*cp = 0;
302 		if (isatty(fd)) {
303 			/* at&t ksh says it prints prompt on fd if it's open
304 			 * for writing and is a tty, but it doesn't do it
305 			 * (it also doesn't check the interactive flag,
306 			 * as is indicated in the Kornshell book).
307 			 */
308 			shellf("%s", cp+1);
309 		}
310 	}
311 
312 	/* If we are reading from the co-process for the first time,
313 	 * make sure the other side of the pipe is closed first.  This allows
314 	 * the detection of eof.
315 	 *
316 	 * This is not compatible with at&t ksh... the fd is kept so another
317 	 * coproc can be started with same output, however, this means eof
318 	 * can't be detected...  This is why it is closed here.
319 	 * If this call is removed, remove the eof check below, too.
320 	 * coproc_readw_close(fd);
321 	 */
322 
323 	if (savehist)
324 		Xinit(xs, xp, 128, ATEMP);
325 	expanding = 0;
326 	Xinit(cs, cp, 128, ATEMP);
327 	for (; *wp != NULL; wp++) {
328 		for (cp = Xstring(cs, cp); ; ) {
329 			if (c == '\n' || c == EOF)
330 				break;
331 			while (1) {
332 				c = shf_getc(shf);
333 				if (c == '\0')
334 					continue;
335 				if (c == EOF && shf_error(shf) &&
336 				    shf->errno_ == EINTR) {
337 					/* Was the offending signal one that
338 					 * would normally kill a process?
339 					 * If so, pretend the read was killed.
340 					 */
341 					ecode = fatal_trap_check();
342 
343 					/* non fatal (eg, CHLD), carry on */
344 					if (!ecode) {
345 						shf_clearerr(shf);
346 						continue;
347 					}
348 				}
349 				break;
350 			}
351 			if (savehist) {
352 				Xcheck(xs, xp);
353 				Xput(xs, xp, c);
354 			}
355 			Xcheck(cs, cp);
356 			if (expanding) {
357 				expanding = 0;
358 				if (c == '\n') {
359 					c = 0;
360 					if (Flag(FTALKING_I) && isatty(fd)) {
361 						/* set prompt in case this is
362 						 * called from .profile or $ENV
363 						 */
364 						set_prompt(PS2);
365 						pprompt(prompt, 0);
366 					}
367 				} else if (c != EOF)
368 					Xput(cs, cp, c);
369 				continue;
370 			}
371 			if (expand && c == '\\') {
372 				expanding = 1;
373 				continue;
374 			}
375 			if (c == '\n' || c == EOF)
376 				break;
377 			if (ctype(c, C_IFS)) {
378 				if (Xlength(cs, cp) == 0 && ctype(c, C_IFSWS))
379 					continue;
380 				if (wp[1])
381 					break;
382 			}
383 			Xput(cs, cp, c);
384 		}
385 		/* strip trailing IFS white space from last variable */
386 		if (!wp[1])
387 			while (Xlength(cs, cp) && ctype(cp[-1], C_IFS) &&
388 			    ctype(cp[-1], C_IFSWS))
389 				cp--;
390 		Xput(cs, cp, '\0');
391 		vp = global(*wp);
392 		/* Must be done before setting export. */
393 		if (vp->flag & RDONLY) {
394 			shf_flush(shf);
395 			bi_errorf("%s is read only", *wp);
396 			return 1;
397 		}
398 		if (Flag(FEXPORT))
399 			typeset(*wp, EXPORT, 0, 0, 0);
400 		if (!setstr(vp, Xstring(cs, cp), KSH_RETURN_ERROR)) {
401 		    shf_flush(shf);
402 		    return 1;
403 		}
404 	}
405 
406 	shf_flush(shf);
407 	if (savehist) {
408 		Xput(xs, xp, '\0');
409 		source->line++;
410 		histsave(source->line, Xstring(xs, xp), 1);
411 		Xfree(xs, xp);
412 	}
413 	/* if this is the co-process fd, close the file descriptor
414 	 * (can get eof if and only if all processes are have died, ie,
415 	 * coproc.njobs is 0 and the pipe is closed).
416 	 */
417 	if (c == EOF && !ecode)
418 		coproc_read_close(fd);
419 
420 	return ecode ? ecode : c == EOF;
421 }
422 
423 int
c_eval(char ** wp)424 c_eval(char **wp)
425 {
426 	struct source *s;
427 	struct source *saves = source;
428 	int savef;
429 	int rv;
430 
431 	if (ksh_getopt(wp, &builtin_opt, null) == '?')
432 		return 1;
433 	s = pushs(SWORDS, ATEMP);
434 	s->u.strv = wp + builtin_opt.optind;
435 	if (!Flag(FPOSIX)) {
436 		/*
437 		 * Handle case where the command is empty due to failed
438 		 * command substitution, eg, eval "$(false)".
439 		 * In this case, shell() will not set/change exstat (because
440 		 * compiled tree is empty), so will use this value.
441 		 * subst_exstat is cleared in execute(), so should be 0 if
442 		 * there were no substitutions.
443 		 *
444 		 * A strict reading of POSIX says we don't do this (though
445 		 * it is traditionally done). [from 1003.2-1992]
446 		 *    3.9.1: Simple Commands
447 		 *	... If there is a command name, execution shall
448 		 *	continue as described in 3.9.1.1.  If there
449 		 *	is no command name, but the command contained a command
450 		 *	substitution, the command shall complete with the exit
451 		 *	status of the last command substitution
452 		 *    3.9.1.1: Command Search and Execution
453 		 *	...(1)...(a) If the command name matches the name of
454 		 *	a special built-in utility, that special built-in
455 		 *	utility shall be invoked.
456 		 * 3.14.5: Eval
457 		 *	... If there are no arguments, or only null arguments,
458 		 *	eval shall return an exit status of zero.
459 		 */
460 		exstat = subst_exstat;
461 	}
462 
463 	savef = Flag(FERREXIT);
464 	Flag(FERREXIT) = 0;
465 	rv = shell(s, false);
466 	Flag(FERREXIT) = savef;
467 	source = saves;
468 	afree(s, ATEMP);
469 	return (rv);
470 }
471 
472 int
c_trap(char ** wp)473 c_trap(char **wp)
474 {
475 	int i;
476 	char *s;
477 	Trap *p;
478 
479 	if (ksh_getopt(wp, &builtin_opt, null) == '?')
480 		return 1;
481 	wp += builtin_opt.optind;
482 
483 	if (*wp == NULL) {
484 		for (p = sigtraps, i = NSIG+1; --i >= 0; p++) {
485 			if (p->trap != NULL) {
486 				shprintf("trap -- ");
487 				print_value_quoted(p->trap);
488 				shprintf(" %s\n", p->name);
489 			}
490 		}
491 		return 0;
492 	}
493 
494 	/*
495 	 * Use case sensitive lookup for first arg so the
496 	 * command 'exit' isn't confused with the pseudo-signal
497 	 * 'EXIT'.
498 	 */
499 	s = (gettrap(*wp, false) == NULL) ? *wp++ : NULL; /* get command */
500 	if (s != NULL && s[0] == '-' && s[1] == '\0')
501 		s = NULL;
502 
503 	/* set/clear traps */
504 	while (*wp != NULL) {
505 		p = gettrap(*wp++, true);
506 		if (p == NULL) {
507 			bi_errorf("bad signal %s", wp[-1]);
508 			return 1;
509 		}
510 		settrap(p, s);
511 	}
512 	return 0;
513 }
514 
515 int
c_exitreturn(char ** wp)516 c_exitreturn(char **wp)
517 {
518 	int how = LEXIT;
519 	int n;
520 	char *arg;
521 
522 	if (ksh_getopt(wp, &builtin_opt, null) == '?')
523 		return 1;
524 	arg = wp[builtin_opt.optind];
525 
526 	if (arg) {
527 		if (!getn(arg, &n)) {
528 			exstat = 1;
529 			warningf(true, "%s: bad number", arg);
530 		} else
531 			exstat = n;
532 	}
533 	if (wp[0][0] == 'r') { /* return */
534 		struct env *ep;
535 
536 		/* need to tell if this is exit or return so trap exit will
537 		 * work right (POSIX)
538 		 */
539 		for (ep = genv; ep; ep = ep->oenv)
540 			if (STOP_RETURN(ep->type)) {
541 				how = LRETURN;
542 				break;
543 			}
544 	}
545 
546 	if (how == LEXIT && !really_exit && j_stopped_running()) {
547 		really_exit = 1;
548 		how = LSHELL;
549 	}
550 
551 	quitenv(NULL);	/* get rid of any i/o redirections */
552 	unwind(how);
553 	/* NOTREACHED */
554 	return 0;
555 }
556 
557 int
c_brkcont(char ** wp)558 c_brkcont(char **wp)
559 {
560 	int n, quit;
561 	struct env *ep, *last_ep = NULL;
562 	char *arg;
563 
564 	if (ksh_getopt(wp, &builtin_opt, null) == '?')
565 		return 1;
566 	arg = wp[builtin_opt.optind];
567 
568 	if (!arg)
569 		n = 1;
570 	else if (!bi_getn(arg, &n))
571 		return 1;
572 	quit = n;
573 	if (quit <= 0) {
574 		/* at&t ksh does this for non-interactive shells only - weird */
575 		bi_errorf("%s: bad value", arg);
576 		return 1;
577 	}
578 
579 	/* Stop at E_NONE, E_PARSE, E_FUNC, or E_INCL */
580 	for (ep = genv; ep && !STOP_BRKCONT(ep->type); ep = ep->oenv)
581 		if (ep->type == E_LOOP) {
582 			if (--quit == 0)
583 				break;
584 			ep->flags |= EF_BRKCONT_PASS;
585 			last_ep = ep;
586 		}
587 
588 	if (quit) {
589 		/* at&t ksh doesn't print a message - just does what it
590 		 * can.  We print a message 'cause it helps in debugging
591 		 * scripts, but don't generate an error (ie, keep going).
592 		 */
593 		if (n == quit) {
594 			warningf(true, "%s: cannot %s", wp[0], wp[0]);
595 			return 0;
596 		}
597 		/* POSIX says if n is too big, the last enclosing loop
598 		 * shall be used.  Doesn't say to print an error but we
599 		 * do anyway 'cause the user messed up.
600 		 */
601 		if (last_ep)
602 			last_ep->flags &= ~EF_BRKCONT_PASS;
603 		warningf(true, "%s: can only %s %d level(s)",
604 		    wp[0], wp[0], n - quit);
605 	}
606 
607 	unwind(*wp[0] == 'b' ? LBREAK : LCONTIN);
608 	/* NOTREACHED */
609 }
610 
611 int
c_set(char ** wp)612 c_set(char **wp)
613 {
614 	int argi, setargs;
615 	struct block *l = genv->loc;
616 	char **owp = wp;
617 
618 	if (wp[1] == NULL) {
619 		static const char *const args [] = { "set", "-", NULL };
620 		return c_typeset((char **) args);
621 	}
622 
623 	argi = parse_args(wp, OF_SET, &setargs);
624 	if (argi < 0)
625 		return 1;
626 	/* set $# and $* */
627 	if (setargs) {
628 		owp = wp += argi - 1;
629 		wp[0] = l->argv[0]; /* save $0 */
630 		while (*++wp != NULL)
631 			*wp = str_save(*wp, &l->area);
632 		l->argc = wp - owp - 1;
633 		l->argv = areallocarray(NULL, l->argc+2, sizeof(char *), &l->area);
634 		for (wp = l->argv; (*wp++ = *owp++) != NULL; )
635 			;
636 	}
637 	/* POSIX says set exit status is 0, but old scripts that use
638 	 * getopt(1), use the construct: set -- `getopt ab:c "$@"`
639 	 * which assumes the exit value set will be that of the ``
640 	 * (subst_exstat is cleared in execute() so that it will be 0
641 	 * if there are no command substitutions).
642 	 */
643 	return Flag(FPOSIX) ? 0 : subst_exstat;
644 }
645 
646 int
c_unset(char ** wp)647 c_unset(char **wp)
648 {
649 	char *id;
650 	int optc, unset_var = 1;
651 
652 	while ((optc = ksh_getopt(wp, &builtin_opt, "fv")) != -1)
653 		switch (optc) {
654 		case 'f':
655 			unset_var = 0;
656 			break;
657 		case 'v':
658 			unset_var = 1;
659 			break;
660 		case '?':
661 			return 1;
662 		}
663 	wp += builtin_opt.optind;
664 	for (; (id = *wp) != NULL; wp++)
665 		if (unset_var) {	/* unset variable */
666 			struct tbl *vp = global(id);
667 
668 			if ((vp->flag&RDONLY)) {
669 				bi_errorf("%s is read only", vp->name);
670 				return 1;
671 			}
672 			unset(vp, strchr(id, '[') ? 1 : 0);
673 		} else {		/* unset function */
674 			define(id, NULL);
675 		}
676 	return 0;
677 }
678 
679 static void
p_tv(struct shf * shf,int posix,struct timeval * tv,int width,char * prefix,char * suffix)680 p_tv(struct shf *shf, int posix, struct timeval *tv, int width, char *prefix,
681     char *suffix)
682 {
683 	struct timespec ts;
684 
685 	TIMEVAL_TO_TIMESPEC(tv, &ts);
686 	p_ts(shf, posix, &ts, width, prefix, suffix);
687 }
688 
689 static void
p_ts(struct shf * shf,int posix,struct timespec * ts,int width,char * prefix,char * suffix)690 p_ts(struct shf *shf, int posix, struct timespec *ts, int width, char *prefix,
691     char *suffix)
692 {
693 	if (posix)
694 		shf_fprintf(shf, "%s%*lld.%02ld%s", prefix ? prefix : "",
695 		    width, (long long)ts->tv_sec, ts->tv_nsec / 10000000,
696 		    suffix);
697 	else
698 		shf_fprintf(shf, "%s%*lldm%02lld.%02lds%s", prefix ? prefix : "",
699 		    width, (long long)ts->tv_sec / 60,
700 		    (long long)ts->tv_sec % 60,
701 		    ts->tv_nsec / 10000000, suffix);
702 }
703 
704 
705 int
c_times(char ** wp)706 c_times(char **wp)
707 {
708 	struct rusage usage;
709 
710 	(void) getrusage(RUSAGE_SELF, &usage);
711 	p_tv(shl_stdout, 0, &usage.ru_utime, 0, NULL, " ");
712 	p_tv(shl_stdout, 0, &usage.ru_stime, 0, NULL, "\n");
713 
714 	(void) getrusage(RUSAGE_CHILDREN, &usage);
715 	p_tv(shl_stdout, 0, &usage.ru_utime, 0, NULL, " ");
716 	p_tv(shl_stdout, 0, &usage.ru_stime, 0, NULL, "\n");
717 
718 	return 0;
719 }
720 
721 /*
722  * time pipeline (really a statement, not a built-in command)
723  */
724 int
timex(struct op * t,int f,volatile int * xerrok)725 timex(struct op *t, int f, volatile int *xerrok)
726 {
727 #define TF_NOARGS	BIT(0)
728 #define TF_NOREAL	BIT(1)		/* don't report real time */
729 #define TF_POSIX	BIT(2)		/* report in posix format */
730 	int rv = 0;
731 	struct rusage ru0, ru1, cru0, cru1;
732 	struct timeval usrtime, systime;
733 	struct timespec ts0, ts1, ts2;
734 	int tf = 0;
735 	extern struct timeval j_usrtime, j_systime; /* computed by j_wait */
736 
737 	clock_gettime(CLOCK_MONOTONIC, &ts0);
738 	getrusage(RUSAGE_SELF, &ru0);
739 	getrusage(RUSAGE_CHILDREN, &cru0);
740 	if (t->left) {
741 		/*
742 		 * Two ways of getting cpu usage of a command: just use t0
743 		 * and t1 (which will get cpu usage from other jobs that
744 		 * finish while we are executing t->left), or get the
745 		 * cpu usage of t->left. at&t ksh does the former, while
746 		 * pdksh tries to do the later (the j_usrtime hack doesn't
747 		 * really work as it only counts the last job).
748 		 */
749 		timerclear(&j_usrtime);
750 		timerclear(&j_systime);
751 		rv = execute(t->left, f | XTIME, xerrok);
752 		if (t->left->type == TCOM)
753 			tf |= t->left->str[0];
754 		clock_gettime(CLOCK_MONOTONIC, &ts1);
755 		getrusage(RUSAGE_SELF, &ru1);
756 		getrusage(RUSAGE_CHILDREN, &cru1);
757 	} else
758 		tf = TF_NOARGS;
759 
760 	if (tf & TF_NOARGS) { /* ksh93 - report shell times (shell+kids) */
761 		tf |= TF_NOREAL;
762 		timeradd(&ru0.ru_utime, &cru0.ru_utime, &usrtime);
763 		timeradd(&ru0.ru_stime, &cru0.ru_stime, &systime);
764 	} else {
765 		timersub(&ru1.ru_utime, &ru0.ru_utime, &usrtime);
766 		timeradd(&usrtime, &j_usrtime, &usrtime);
767 		timersub(&ru1.ru_stime, &ru0.ru_stime, &systime);
768 		timeradd(&systime, &j_systime, &systime);
769 	}
770 
771 	if (!(tf & TF_NOREAL)) {
772 		timespecsub(&ts1, &ts0, &ts2);
773 		if (tf & TF_POSIX)
774 			p_ts(shl_out, 1, &ts2, 5, "real ", "\n");
775 		else
776 			p_ts(shl_out, 0, &ts2, 5, NULL, " real ");
777 	}
778 	if (tf & TF_POSIX)
779 		p_tv(shl_out, 1, &usrtime, 5, "user ", "\n");
780 	else
781 		p_tv(shl_out, 0, &usrtime, 5, NULL, " user ");
782 	if (tf & TF_POSIX)
783 		p_tv(shl_out, 1, &systime, 5, "sys  ", "\n");
784 	else
785 		p_tv(shl_out, 0, &systime, 5, NULL, " system\n");
786 	shf_flush(shl_out);
787 
788 	return rv;
789 }
790 
791 void
timex_hook(struct op * t,char ** volatile * app)792 timex_hook(struct op *t, char **volatile *app)
793 {
794 	char **wp = *app;
795 	int optc;
796 	int i, j;
797 	Getopt opt;
798 
799 	ksh_getopt_reset(&opt, 0);
800 	opt.optind = 0;	/* start at the start */
801 	while ((optc = ksh_getopt(wp, &opt, ":p")) != -1)
802 		switch (optc) {
803 		case 'p':
804 			t->str[0] |= TF_POSIX;
805 			break;
806 		case '?':
807 			errorf("time: -%s unknown option", opt.optarg);
808 		case ':':
809 			errorf("time: -%s requires an argument",
810 			    opt.optarg);
811 		}
812 	/* Copy command words down over options. */
813 	if (opt.optind != 0) {
814 		for (i = 0; i < opt.optind; i++)
815 			afree(wp[i], ATEMP);
816 		for (i = 0, j = opt.optind; (wp[i] = wp[j]); i++, j++)
817 			;
818 	}
819 	if (!wp[0])
820 		t->str[0] |= TF_NOARGS;
821 	*app = wp;
822 }
823 
824 /* exec with no args - args case is taken care of in comexec() */
825 int
c_exec(char ** wp)826 c_exec(char **wp)
827 {
828 	int i;
829 
830 	/* make sure redirects stay in place */
831 	if (genv->savefd != NULL) {
832 		for (i = 0; i < NUFILE; i++) {
833 			if (genv->savefd[i] > 0)
834 				close(genv->savefd[i]);
835 			/*
836 			 * For ksh keep anything > 2 private,
837 			 * for sh, let them be (POSIX says what
838 			 * happens is unspecified and the bourne shell
839 			 * keeps them open).
840 			 */
841 			if (!Flag(FSH) && i > 2 && genv->savefd[i])
842 				fcntl(i, F_SETFD, FD_CLOEXEC);
843 		}
844 		genv->savefd = NULL;
845 	}
846 	return 0;
847 }
848 
849 static int
c_suspend(char ** wp)850 c_suspend(char **wp)
851 {
852 	if (wp[1] != NULL) {
853 		bi_errorf("too many arguments");
854 		return 1;
855 	}
856 	if (Flag(FLOGIN)) {
857 		/* Can't suspend an orphaned process group. */
858 		pid_t parent = getppid();
859 		if (getpgid(parent) == getpgid(0) ||
860 		    getsid(parent) != getsid(0)) {
861 			bi_errorf("can't suspend a login shell");
862 			return 1;
863 		}
864 	}
865 	j_suspend();
866 	return 0;
867 }
868 
869 /* dummy function, special case in comexec() */
870 int
c_builtin(char ** wp)871 c_builtin(char **wp)
872 {
873 	return 0;
874 }
875 
876 extern	int c_test(char **wp);			/* in c_test.c */
877 extern	int c_ulimit(char **wp);		/* in c_ulimit.c */
878 
879 /* A leading = means assignments before command are kept;
880  * a leading * means a POSIX special builtin;
881  * a leading + means a POSIX regular builtin
882  * (* and + should not be combined).
883  */
884 const struct builtin shbuiltins [] = {
885 	{"*=.", c_dot},
886 	{"*=:", c_label},
887 	{"[", c_test},
888 	{"*=break", c_brkcont},
889 	{"=builtin", c_builtin},
890 	{"*=continue", c_brkcont},
891 	{"*=eval", c_eval},
892 	{"*=exec", c_exec},
893 	{"*=exit", c_exitreturn},
894 	{"+false", c_label},
895 	{"*=return", c_exitreturn},
896 	{"*=set", c_set},
897 	{"*=shift", c_shift},
898 	{"*=times", c_times},
899 	{"*=trap", c_trap},
900 	{"+=wait", c_wait},
901 	{"+read", c_read},
902 	{"test", c_test},
903 	{"+true", c_label},
904 	{"ulimit", c_ulimit},
905 	{"+umask", c_umask},
906 	{"*=unset", c_unset},
907 	{"suspend", c_suspend},
908 	{NULL, NULL}
909 };
910