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1 /*	$OpenBSD: exec.c,v 1.49 2009/01/29 23:27:26 jaredy Exp $	*/
2 
3 /*-
4  * Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
5  *	Thorsten Glaser <tg@mirbsd.org>
6  *
7  * Provided that these terms and disclaimer and all copyright notices
8  * are retained or reproduced in an accompanying document, permission
9  * is granted to deal in this work without restriction, including un-
10  * limited rights to use, publicly perform, distribute, sell, modify,
11  * merge, give away, or sublicence.
12  *
13  * This work is provided "AS IS" and WITHOUT WARRANTY of any kind, to
14  * the utmost extent permitted by applicable law, neither express nor
15  * implied; without malicious intent or gross negligence. In no event
16  * may a licensor, author or contributor be held liable for indirect,
17  * direct, other damage, loss, or other issues arising in any way out
18  * of dealing in the work, even if advised of the possibility of such
19  * damage or existence of a defect, except proven that it results out
20  * of said person's immediate fault when using the work as intended.
21  */
22 
23 #include "sh.h"
24 
25 __RCSID("$MirOS: src/bin/mksh/exec.c,v 1.96 2011/09/07 15:24:14 tg Exp $");
26 
27 #ifndef MKSH_DEFAULT_EXECSHELL
28 #define MKSH_DEFAULT_EXECSHELL	"/bin/sh"
29 #endif
30 
31 static int comexec(struct op *, struct tbl * volatile, const char **,
32     int volatile, volatile int *);
33 static void scriptexec(struct op *, const char **) MKSH_A_NORETURN;
34 static int call_builtin(struct tbl *, const char **);
35 static int iosetup(struct ioword *, struct tbl *);
36 static int herein(const char *, int, char **);
37 static const char *do_selectargs(const char **, bool);
38 static Test_op dbteste_isa(Test_env *, Test_meta);
39 static const char *dbteste_getopnd(Test_env *, Test_op, bool);
40 static void dbteste_error(Test_env *, int, const char *);
41 static int search_access(const char *, int);
42 
43 /*
44  * execute command tree
45  */
46 int
execute(struct op * volatile t,volatile int flags,volatile int * volatile xerrok)47 execute(struct op * volatile t,
48     /* if XEXEC don't fork */
49     volatile int flags,
50     volatile int * volatile xerrok)
51 {
52 	int i;
53 	volatile int rv = 0, dummy = 0;
54 	int pv[2];
55 	const char ** volatile ap = NULL;
56 	char ** volatile up;
57 	const char *s, *ccp;
58 	struct ioword **iowp;
59 	struct tbl *tp = NULL;
60 	char *cp;
61 
62 	if (t == NULL)
63 		return (0);
64 
65 	/* Caller doesn't care if XERROK should propagate. */
66 	if (xerrok == NULL)
67 		xerrok = &dummy;
68 
69 	if ((flags&XFORK) && !(flags&XEXEC) && t->type != TPIPE)
70 		/* run in sub-process */
71 		return (exchild(t, flags & ~XTIME, xerrok, -1));
72 
73 	newenv(E_EXEC);
74 	if (trap)
75 		runtraps(0);
76 
77 	/* we want to run an executable, do some variance checks */
78 	if (t->type == TCOM) {
79 		/* check if this is 'var=<<EOF' */
80 		if (
81 		    /* we have zero arguments, i.e. no programme to run */
82 		    t->args[0] == NULL &&
83 		    /* we have exactly one variable assignment */
84 		    t->vars[0] != NULL && t->vars[1] == NULL &&
85 		    /* we have exactly one I/O redirection */
86 		    t->ioact != NULL && t->ioact[0] != NULL &&
87 		    t->ioact[1] == NULL &&
88 		    /* of type "here document" (or "here string") */
89 		    (t->ioact[0]->flag & IOTYPE) == IOHERE &&
90 		    /* the variable assignment begins with a valid varname */
91 		    (ccp = skip_wdvarname(t->vars[0], true)) != t->vars[0] &&
92 		    /* and has no right-hand side (i.e. "varname=") */
93 		    ccp[0] == CHAR && ccp[1] == '=' && ccp[2] == EOS &&
94 		    /* plus we can have a here document content */
95 		    herein(t->ioact[0]->heredoc, t->ioact[0]->flag & IOEVAL,
96 		    &cp) == 0 && cp && *cp) {
97 			char *sp = cp, *dp;
98 			size_t n = ccp - t->vars[0] + 2, z;
99 
100 			/* drop redirection (will be garbage collected) */
101 			t->ioact = NULL;
102 
103 			/* set variable to its expanded value */
104 			z = strlen(cp) + 1;
105 			if (notoktomul(z, 2) || notoktoadd(z * 2, n))
106 				internal_errorf(Toomem, (unsigned long)-1);
107 			dp = alloc(z * 2 + n, ATEMP);
108 			memcpy(dp, t->vars[0], n);
109 			t->vars[0] = dp;
110 			dp += n;
111 			while (*sp) {
112 				*dp++ = QCHAR;
113 				*dp++ = *sp++;
114 			}
115 			*dp = EOS;
116 			/* free the expanded value */
117 			afree(cp, APERM);
118 		}
119 
120 		/*
121 		 * Clear subst_exstat before argument expansion. Used by
122 		 * null commands (see comexec() and c_eval()) and by c_set().
123 		 */
124 		subst_exstat = 0;
125 
126 		/* for $LINENO */
127 		current_lineno = t->lineno;
128 
129 		/*
130 		 * POSIX says expand command words first, then redirections,
131 		 * and assignments last..
132 		 */
133 		up = eval(t->args, t->u.evalflags | DOBLANK | DOGLOB | DOTILDE);
134 		if (flags & XTIME)
135 			/* Allow option parsing (bizarre, but POSIX) */
136 			timex_hook(t, &up);
137 		ap = (const char **)up;
138 		if (Flag(FXTRACE) && ap[0]) {
139 			shf_puts(substitute(str_val(global("PS4")), 0),
140 			    shl_out);
141 			for (i = 0; ap[i]; i++)
142 				shf_fprintf(shl_out, "%s%c", ap[i],
143 				    ap[i + 1] ? ' ' : '\n');
144 			shf_flush(shl_out);
145 		}
146 		if (ap[0])
147 			tp = findcom(ap[0], FC_BI|FC_FUNC);
148 	}
149 	flags &= ~XTIME;
150 
151 	if (t->ioact != NULL || t->type == TPIPE || t->type == TCOPROC) {
152 		e->savefd = alloc2(NUFILE, sizeof(short), ATEMP);
153 		/* initialise to not redirected */
154 		memset(e->savefd, 0, NUFILE * sizeof(short));
155 	}
156 
157 	/* mark for replacement later (unless TPIPE) */
158 	vp_pipest->flag |= INT_L;
159 
160 	/* do redirection, to be restored in quitenv() */
161 	if (t->ioact != NULL)
162 		for (iowp = t->ioact; *iowp != NULL; iowp++) {
163 			if (iosetup(*iowp, tp) < 0) {
164 				exstat = rv = 1;
165 				/*
166 				 * Redirection failures for special commands
167 				 * cause (non-interactive) shell to exit.
168 				 */
169 				if (tp && tp->type == CSHELL &&
170 				    (tp->flag & SPEC_BI))
171 					errorfz();
172 				/* Deal with FERREXIT, quitenv(), etc. */
173 				goto Break;
174 			}
175 		}
176 
177 	switch (t->type) {
178 	case TCOM:
179 		rv = comexec(t, tp, (const char **)ap, flags, xerrok);
180 		break;
181 
182 	case TPAREN:
183 		rv = execute(t->left, flags | XFORK, xerrok);
184 		break;
185 
186 	case TPIPE:
187 		flags |= XFORK;
188 		flags &= ~XEXEC;
189 		e->savefd[0] = savefd(0);
190 		e->savefd[1] = savefd(1);
191 		while (t->type == TPIPE) {
192 			openpipe(pv);
193 			/* stdout of curr */
194 			ksh_dup2(pv[1], 1, false);
195 			/**
196 			 * Let exchild() close pv[0] in child
197 			 * (if this isn't done, commands like
198 			 *	(: ; cat /etc/termcap) | sleep 1
199 			 * will hang forever).
200 			 */
201 			exchild(t->left, flags | XPIPEO | XCCLOSE,
202 			    NULL, pv[0]);
203 			/* stdin of next */
204 			ksh_dup2(pv[0], 0, false);
205 			closepipe(pv);
206 			flags |= XPIPEI;
207 			t = t->right;
208 		}
209 		/* stdout of last */
210 		restfd(1, e->savefd[1]);
211 		/* no need to re-restore this */
212 		e->savefd[1] = 0;
213 		/* Let exchild() close 0 in parent, after fork, before wait */
214 		i = exchild(t, flags | XPCLOSE | XPIPEST, xerrok, 0);
215 		if (!(flags&XBGND) && !(flags&XXCOM))
216 			rv = i;
217 		break;
218 
219 	case TLIST:
220 		while (t->type == TLIST) {
221 			execute(t->left, flags & XERROK, NULL);
222 			t = t->right;
223 		}
224 		rv = execute(t, flags & XERROK, xerrok);
225 		break;
226 
227 	case TCOPROC: {
228 #ifndef MKSH_NOPROSPECTOFWORK
229 		sigset_t omask;
230 
231 		/*
232 		 * Block sigchild as we are using things changed in the
233 		 * signal handler
234 		 */
235 		sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
236 		e->type = E_ERRH;
237 		i = sigsetjmp(e->jbuf, 0);
238 		if (i) {
239 			sigprocmask(SIG_SETMASK, &omask, NULL);
240 			quitenv(NULL);
241 			unwind(i);
242 			/* NOTREACHED */
243 		}
244 #endif
245 		/* Already have a (live) co-process? */
246 		if (coproc.job && coproc.write >= 0)
247 			errorf("coprocess already exists");
248 
249 		/* Can we re-use the existing co-process pipe? */
250 		coproc_cleanup(true);
251 
252 		/* do this before opening pipes, in case these fail */
253 		e->savefd[0] = savefd(0);
254 		e->savefd[1] = savefd(1);
255 
256 		openpipe(pv);
257 		if (pv[0] != 0) {
258 			ksh_dup2(pv[0], 0, false);
259 			close(pv[0]);
260 		}
261 		coproc.write = pv[1];
262 		coproc.job = NULL;
263 
264 		if (coproc.readw >= 0)
265 			ksh_dup2(coproc.readw, 1, false);
266 		else {
267 			openpipe(pv);
268 			coproc.read = pv[0];
269 			ksh_dup2(pv[1], 1, false);
270 			/* closed before first read */
271 			coproc.readw = pv[1];
272 			coproc.njobs = 0;
273 			/* create new coprocess id */
274 			++coproc.id;
275 		}
276 #ifndef MKSH_NOPROSPECTOFWORK
277 		sigprocmask(SIG_SETMASK, &omask, NULL);
278 		/* no more need for error handler */
279 		e->type = E_EXEC;
280 #endif
281 
282 		/*
283 		 * exchild() closes coproc.* in child after fork,
284 		 * will also increment coproc.njobs when the
285 		 * job is actually created.
286 		 */
287 		flags &= ~XEXEC;
288 		exchild(t->left, flags | XBGND | XFORK | XCOPROC | XCCLOSE,
289 		    NULL, coproc.readw);
290 		break;
291 	}
292 
293 	case TASYNC:
294 		/*
295 		 * XXX non-optimal, I think - "(foo &)", forks for (),
296 		 * forks again for async... parent should optimise
297 		 * this to "foo &"...
298 		 */
299 		rv = execute(t->left, (flags&~XEXEC)|XBGND|XFORK, xerrok);
300 		break;
301 
302 	case TOR:
303 	case TAND:
304 		rv = execute(t->left, XERROK, xerrok);
305 		if ((rv == 0) == (t->type == TAND))
306 			rv = execute(t->right, XERROK, xerrok);
307 		flags |= XERROK;
308 		if (xerrok)
309 			*xerrok = 1;
310 		break;
311 
312 	case TBANG:
313 		rv = !execute(t->right, XERROK, xerrok);
314 		flags |= XERROK;
315 		if (xerrok)
316 			*xerrok = 1;
317 		break;
318 
319 	case TDBRACKET: {
320 		Test_env te;
321 
322 		te.flags = TEF_DBRACKET;
323 		te.pos.wp = t->args;
324 		te.isa = dbteste_isa;
325 		te.getopnd = dbteste_getopnd;
326 		te.eval = test_eval;
327 		te.error = dbteste_error;
328 
329 		rv = test_parse(&te);
330 		break;
331 	}
332 
333 	case TFOR:
334 	case TSELECT: {
335 		volatile bool is_first = true;
336 		ap = (t->vars == NULL) ? e->loc->argv + 1 :
337 		    (const char **)eval((const char **)t->vars,
338 		    DOBLANK | DOGLOB | DOTILDE);
339 		e->type = E_LOOP;
340 		while (/* CONSTCOND */ 1) {
341 			i = sigsetjmp(e->jbuf, 0);
342 			if (!i)
343 				break;
344 			if ((e->flags&EF_BRKCONT_PASS) ||
345 			    (i != LBREAK && i != LCONTIN)) {
346 				quitenv(NULL);
347 				unwind(i);
348 			} else if (i == LBREAK) {
349 				rv = 0;
350 				goto Break;
351 			}
352 		}
353 		/* in case of a continue */
354 		rv = 0;
355 		if (t->type == TFOR) {
356 			while (*ap != NULL) {
357 				setstr(global(t->str), *ap++, KSH_UNWIND_ERROR);
358 				rv = execute(t->left, flags & XERROK, xerrok);
359 			}
360 		} else {
361 			/* TSELECT */
362 			for (;;) {
363 				if (!(ccp = do_selectargs(ap, is_first))) {
364 					rv = 1;
365 					break;
366 				}
367 				is_first = false;
368 				setstr(global(t->str), ccp, KSH_UNWIND_ERROR);
369 				execute(t->left, flags & XERROK, xerrok);
370 			}
371 		}
372 		break;
373 	}
374 
375 	case TWHILE:
376 	case TUNTIL:
377 		e->type = E_LOOP;
378 		while (/* CONSTCOND */ 1) {
379 			i = sigsetjmp(e->jbuf, 0);
380 			if (!i)
381 				break;
382 			if ((e->flags&EF_BRKCONT_PASS) ||
383 			    (i != LBREAK && i != LCONTIN)) {
384 				quitenv(NULL);
385 				unwind(i);
386 			} else if (i == LBREAK) {
387 				rv = 0;
388 				goto Break;
389 			}
390 		}
391 		/* in case of a continue */
392 		rv = 0;
393 		while ((execute(t->left, XERROK, NULL) == 0) ==
394 		    (t->type == TWHILE))
395 			rv = execute(t->right, flags & XERROK, xerrok);
396 		break;
397 
398 	case TIF:
399 	case TELIF:
400 		if (t->right == NULL)
401 			/* should be error */
402 			break;
403 		rv = execute(t->left, XERROK, NULL) == 0 ?
404 		    execute(t->right->left, flags & XERROK, xerrok) :
405 		    execute(t->right->right, flags & XERROK, xerrok);
406 		break;
407 
408 	case TCASE:
409 		i = 0;
410 		ccp = evalstr(t->str, DOTILDE);
411 		for (t = t->left; t != NULL && t->type == TPAT; t = t->right) {
412 			for (ap = (const char **)t->vars; *ap; ap++) {
413 				if (i || ((s = evalstr(*ap, DOTILDE|DOPAT)) &&
414 				    gmatchx(ccp, s, false))) {
415 					rv = execute(t->left, flags & XERROK,
416 					    xerrok);
417 					i = 0;
418 					switch (t->u.charflag) {
419 					case '&':
420 						i = 1;
421 						/* FALLTHROUGH */
422 					case '|':
423 						goto TCASE_next;
424 					}
425 					goto TCASE_out;
426 				}
427 			}
428 			i = 0;
429  TCASE_next:
430 			/* empty */;
431 		}
432  TCASE_out:
433 		break;
434 
435 	case TBRACE:
436 		rv = execute(t->left, flags & XERROK, xerrok);
437 		break;
438 
439 	case TFUNCT:
440 		rv = define(t->str, t);
441 		break;
442 
443 	case TTIME:
444 		/*
445 		 * Clear XEXEC so nested execute() call doesn't exit
446 		 * (allows "ls -l | time grep foo").
447 		 */
448 		rv = timex(t, flags & ~XEXEC, xerrok);
449 		break;
450 
451 	case TEXEC:
452 		/* an eval'd TCOM */
453 		s = t->args[0];
454 		up = makenv();
455 		restoresigs();
456 		cleanup_proc_env();
457 		{
458 			union mksh_ccphack cargs;
459 
460 			cargs.ro = t->args;
461 			execve(t->str, cargs.rw, up);
462 			rv = errno;
463 		}
464 		if (rv == ENOEXEC)
465 			scriptexec(t, (const char **)up);
466 		else
467 			errorf("%s: %s", s, strerror(rv));
468 	}
469  Break:
470 	exstat = rv;
471 	if (vp_pipest->flag & INT_L) {
472 		unset(vp_pipest, 1);
473 		vp_pipest->flag = DEFINED | ISSET | INTEGER | RDONLY |
474 		    ARRAY | INT_U;
475 		vp_pipest->val.i = rv;
476 	}
477 
478 	/* restores IO */
479 	quitenv(NULL);
480 	if ((flags&XEXEC))
481 		/* exit child */
482 		unwind(LEXIT);
483 	if (rv != 0 && !(flags & XERROK) &&
484 	    (xerrok == NULL || !*xerrok)) {
485 		trapsig(ksh_SIGERR);
486 		if (Flag(FERREXIT))
487 			unwind(LERROR);
488 	}
489 	return (rv);
490 }
491 
492 /*
493  * execute simple command
494  */
495 
496 static int
comexec(struct op * t,struct tbl * volatile tp,const char ** ap,volatile int flags,volatile int * xerrok)497 comexec(struct op *t, struct tbl * volatile tp, const char **ap,
498     volatile int flags, volatile int *xerrok)
499 {
500 	int i;
501 	volatile int rv = 0;
502 	const char *cp;
503 	const char **lastp;
504 	/* Must be static (XXX but why?) */
505 	static struct op texec;
506 	int type_flags;
507 	int keepasn_ok;
508 	int fcflags = FC_BI|FC_FUNC|FC_PATH;
509 	bool bourne_function_call = false;
510 	struct block *l_expand, *l_assign;
511 
512 	/*
513 	 * snag the last argument for $_ XXX not the same as AT&T ksh,
514 	 * which only seems to set $_ after a newline (but not in
515 	 * functions/dot scripts, but in interactive and script) -
516 	 * perhaps save last arg here and set it in shell()?.
517 	 */
518 	if (Flag(FTALKING) && *(lastp = ap)) {
519 		while (*++lastp)
520 			;
521 		/* setstr() can't fail here */
522 		setstr(typeset("_", LOCAL, 0, INTEGER, 0), *--lastp,
523 		    KSH_RETURN_ERROR);
524 	}
525 
526 	/**
527 	 * Deal with the shell builtins builtin, exec and command since
528 	 * they can be followed by other commands. This must be done before
529 	 * we know if we should create a local block which must be done
530 	 * before we can do a path search (in case the assignments change
531 	 * PATH).
532 	 * Odd cases:
533 	 *	FOO=bar exec >/dev/null		FOO is kept but not exported
534 	 *	FOO=bar exec foobar		FOO is exported
535 	 *	FOO=bar command exec >/dev/null	FOO is neither kept nor exported
536 	 *	FOO=bar command			FOO is neither kept nor exported
537 	 *	PATH=... foobar			use new PATH in foobar search
538 	 */
539 	keepasn_ok = 1;
540 	while (tp && tp->type == CSHELL) {
541 		/* undo effects of command */
542 		fcflags = FC_BI|FC_FUNC|FC_PATH;
543 		if (tp->val.f == c_builtin) {
544 			if ((cp = *++ap) == NULL ||
545 			    (!strcmp(cp, "--") && (cp = *++ap) == NULL)) {
546 				tp = NULL;
547 				break;
548 			}
549 			if ((tp = findcom(cp, FC_BI)) == NULL)
550 				errorf("%s: %s: %s", Tbuiltin, cp, "not a builtin");
551 			continue;
552 		} else if (tp->val.f == c_exec) {
553 			if (ap[1] == NULL)
554 				break;
555 			ap++;
556 			flags |= XEXEC;
557 		} else if (tp->val.f == c_command) {
558 			int optc, saw_p = 0;
559 
560 			/*
561 			 * Ugly dealing with options in two places (here
562 			 * and in c_command(), but such is life)
563 			 */
564 			ksh_getopt_reset(&builtin_opt, 0);
565 			while ((optc = ksh_getopt(ap, &builtin_opt, ":p")) == 'p')
566 				saw_p = 1;
567 			if (optc != EOF)
568 				/* command -vV or something */
569 				break;
570 			/* don't look for functions */
571 			fcflags = FC_BI|FC_PATH;
572 			if (saw_p) {
573 				if (Flag(FRESTRICTED)) {
574 					warningf(true, "%s: %s",
575 					    "command -p", "restricted");
576 					rv = 1;
577 					goto Leave;
578 				}
579 				fcflags |= FC_DEFPATH;
580 			}
581 			ap += builtin_opt.optind;
582 			/*
583 			 * POSIX says special builtins lose their status
584 			 * if accessed using command.
585 			 */
586 			keepasn_ok = 0;
587 			if (!ap[0]) {
588 				/* ensure command with no args exits with 0 */
589 				subst_exstat = 0;
590 				break;
591 			}
592 #ifndef MKSH_NO_EXTERNAL_CAT
593 		} else if (tp->val.f == c_cat) {
594 			/*
595 			 * if we have any flags, do not use the builtin
596 			 * in theory, we could allow -u, but that would
597 			 * mean to use ksh_getopt here and possibly ad-
598 			 * ded complexity and more code and isn't worth
599 			 * additional hassle (and the builtin must call
600 			 * ksh_getopt already but can't come back here)
601 			 */
602 			if (ap[1] && ap[1][0] == '-' && ap[1][1] != '\0' &&
603 			    /* argument, begins with -, is not - or -- */
604 			    (ap[1][1] != '-' || ap[1][2] != '\0'))
605 				/* don't look for builtins or functions */
606 				fcflags = FC_PATH;
607 			else
608 				/* go on, use the builtin */
609 				break;
610 #endif
611 		} else
612 			break;
613 		tp = findcom(ap[0], fcflags & (FC_BI|FC_FUNC));
614 	}
615 	l_expand = e->loc;
616 	if (keepasn_ok && (!ap[0] || (tp && (tp->flag & KEEPASN))))
617 		type_flags = 0;
618 	else {
619 		/* create new variable/function block */
620 		newblock();
621 		/* ksh functions don't keep assignments, POSIX functions do. */
622 		if (keepasn_ok && tp && tp->type == CFUNC &&
623 		    !(tp->flag & FKSH)) {
624 			bourne_function_call = true;
625 			type_flags = EXPORT;
626 		} else
627 			type_flags = LOCAL|LOCAL_COPY|EXPORT;
628 	}
629 	l_assign = e->loc;
630 	if (Flag(FEXPORT))
631 		type_flags |= EXPORT;
632 	for (i = 0; t->vars[i]; i++) {
633 		/* do NOT lookup in the new var/fn block just created */
634 		e->loc = l_expand;
635 		cp = evalstr(t->vars[i], DOASNTILDE);
636 		e->loc = l_assign;
637 		/* but assign in there as usual */
638 
639 		if (Flag(FXTRACE)) {
640 			if (i == 0)
641 				shf_puts(substitute(str_val(global("PS4")), 0),
642 				    shl_out);
643 			shf_fprintf(shl_out, "%s%c", cp,
644 			    t->vars[i + 1] ? ' ' : '\n');
645 			if (!t->vars[i + 1])
646 				shf_flush(shl_out);
647 		}
648 		typeset(cp, type_flags, 0, 0, 0);
649 		if (bourne_function_call && !(type_flags & EXPORT))
650 			typeset(cp, LOCAL|LOCAL_COPY|EXPORT, 0, 0, 0);
651 	}
652 
653 	if ((cp = *ap) == NULL) {
654 		rv = subst_exstat;
655 		goto Leave;
656 	} else if (!tp) {
657 		if (Flag(FRESTRICTED) && vstrchr(cp, '/')) {
658 			warningf(true, "%s: %s", cp, "restricted");
659 			rv = 1;
660 			goto Leave;
661 		}
662 		tp = findcom(cp, fcflags);
663 	}
664 
665 	switch (tp->type) {
666 
667 	/* shell built-in */
668 	case CSHELL:
669 		rv = call_builtin(tp, (const char **)ap);
670 		break;
671 
672 	/* function call */
673 	case CFUNC: {
674 		volatile unsigned char old_xflag;
675 		volatile uint32_t old_inuse;
676 		const char * volatile old_kshname;
677 
678 		if (!(tp->flag & ISSET)) {
679 			struct tbl *ftp;
680 
681 			if (!tp->u.fpath) {
682 				rv = (tp->u2.errnov == ENOENT) ? 127 : 126;
683 				warningf(true, "%s: %s %s: %s", cp,
684 				    "can't find", "function definition file",
685 				    strerror(tp->u2.errnov));
686 				break;
687 			}
688 			if (include(tp->u.fpath, 0, NULL, 0) < 0) {
689 				rv = errno;
690 				warningf(true, "%s: %s %s %s: %s", cp,
691 				    "can't open", "function definition file",
692 				    tp->u.fpath, strerror(rv));
693 				rv = 127;
694 				break;
695 			}
696 			if (!(ftp = findfunc(cp, hash(cp), false)) ||
697 			    !(ftp->flag & ISSET)) {
698 				warningf(true, "%s: %s %s", cp,
699 				    "function not defined by", tp->u.fpath);
700 				rv = 127;
701 				break;
702 			}
703 			tp = ftp;
704 		}
705 
706 		/*
707 		 * ksh functions set $0 to function name, POSIX
708 		 * functions leave $0 unchanged.
709 		 */
710 		old_kshname = kshname;
711 		if (tp->flag & FKSH)
712 			kshname = ap[0];
713 		else
714 			ap[0] = kshname;
715 		e->loc->argv = ap;
716 		for (i = 0; *ap++ != NULL; i++)
717 			;
718 		e->loc->argc = i - 1;
719 		/*
720 		 * ksh-style functions handle getopts sanely,
721 		 * Bourne/POSIX functions are insane...
722 		 */
723 		if (tp->flag & FKSH) {
724 			e->loc->flags |= BF_DOGETOPTS;
725 			e->loc->getopts_state = user_opt;
726 			getopts_reset(1);
727 		}
728 
729 		old_xflag = Flag(FXTRACE);
730 		Flag(FXTRACE) |= tp->flag & TRACE ? 1 : 0;
731 
732 		old_inuse = tp->flag & FINUSE;
733 		tp->flag |= FINUSE;
734 
735 		e->type = E_FUNC;
736 		i = sigsetjmp(e->jbuf, 0);
737 		if (i == 0) {
738 			/* seems odd to pass XERROK here, but AT&T ksh does */
739 			exstat = execute(tp->val.t, flags & XERROK, xerrok);
740 			i = LRETURN;
741 		}
742 		kshname = old_kshname;
743 		Flag(FXTRACE) = old_xflag;
744 		tp->flag = (tp->flag & ~FINUSE) | old_inuse;
745 		/*
746 		 * Were we deleted while executing? If so, free the
747 		 * execution tree. TODO: Unfortunately, the table entry
748 		 * is never re-used until the lookup table is expanded.
749 		 */
750 		if ((tp->flag & (FDELETE|FINUSE)) == FDELETE) {
751 			if (tp->flag & ALLOC) {
752 				tp->flag &= ~ALLOC;
753 				tfree(tp->val.t, tp->areap);
754 			}
755 			tp->flag = 0;
756 		}
757 		switch (i) {
758 		case LRETURN:
759 		case LERROR:
760 			rv = exstat;
761 			break;
762 		case LINTR:
763 		case LEXIT:
764 		case LLEAVE:
765 		case LSHELL:
766 			quitenv(NULL);
767 			unwind(i);
768 			/* NOTREACHED */
769 		default:
770 			quitenv(NULL);
771 			internal_errorf("%s %d", "CFUNC", i);
772 		}
773 		break;
774 	}
775 
776 	/* executable command */
777 	case CEXEC:
778 	/* tracked alias */
779 	case CTALIAS:
780 		if (!(tp->flag&ISSET)) {
781 			if (tp->u2.errnov == ENOENT) {
782 				rv = 127;
783 				warningf(true, "%s: %s", cp, "not found");
784 			} else {
785 				rv = 126;
786 				warningf(true, "%s: %s: %s", cp, "can't execute",
787 				    strerror(tp->u2.errnov));
788 			}
789 			break;
790 		}
791 
792 		/* set $_ to programme's full path */
793 		/* setstr() can't fail here */
794 		setstr(typeset("_", LOCAL|EXPORT, 0, INTEGER, 0),
795 		    tp->val.s, KSH_RETURN_ERROR);
796 
797 		if (flags&XEXEC) {
798 			j_exit();
799 			if (!(flags&XBGND)
800 #ifndef MKSH_UNEMPLOYED
801 			    || Flag(FMONITOR)
802 #endif
803 			    ) {
804 				setexecsig(&sigtraps[SIGINT], SS_RESTORE_ORIG);
805 				setexecsig(&sigtraps[SIGQUIT], SS_RESTORE_ORIG);
806 			}
807 		}
808 
809 		/* to fork we set up a TEXEC node and call execute */
810 		texec.type = TEXEC;
811 		/* for tprint */
812 		texec.left = t;
813 		texec.str = tp->val.s;
814 		texec.args = ap;
815 		rv = exchild(&texec, flags, xerrok, -1);
816 		break;
817 	}
818  Leave:
819 	if (flags & XEXEC) {
820 		exstat = rv;
821 		unwind(LLEAVE);
822 	}
823 	return (rv);
824 }
825 
826 static void
scriptexec(struct op * tp,const char ** ap)827 scriptexec(struct op *tp, const char **ap)
828 {
829 	const char *sh;
830 #ifndef MKSH_SMALL
831 	unsigned char *cp;
832 	/* 64 == MAXINTERP in MirBSD <sys/param.h> */
833 	char buf[64];
834 	int fd;
835 #endif
836 	union mksh_ccphack args, cap;
837 
838 	sh = str_val(global("EXECSHELL"));
839 	if (sh && *sh)
840 		sh = search_path(sh, path, X_OK, NULL);
841 	if (!sh || !*sh)
842 		sh = MKSH_DEFAULT_EXECSHELL;
843 
844 	*tp->args-- = tp->str;
845 
846 #ifndef MKSH_SMALL
847 	if ((fd = open(tp->str, O_RDONLY)) >= 0) {
848 		/* read first MAXINTERP octets from file */
849 		if (read(fd, buf, sizeof(buf)) <= 0)
850 			/* read error -> no good */
851 			buf[0] = '\0';
852 		close(fd);
853 
854 		/* skip UTF-8 Byte Order Mark, if present */
855 		cp = (unsigned char *)buf;
856 		if ((cp[0] == 0xEF) && (cp[1] == 0xBB) && (cp[2] == 0xBF))
857 			cp += 3;
858 		/* save begin of shebang for later */
859 		fd = (char *)cp - buf;		/* either 0 or (if BOM) 3 */
860 
861 		/* scan for newline (or CR) or NUL _before_ end of buffer */
862 		while ((char *)cp < (buf + sizeof(buf)))
863 			if (*cp == '\0' || *cp == '\n' || *cp == '\r') {
864 				*cp = '\0';
865 				break;
866 			} else
867 				++cp;
868 		/* if the shebang line is longer than MAXINTERP, bail out */
869 		if ((char *)cp >= (buf + sizeof(buf)))
870 			goto noshebang;
871 
872 		/* restore begin of shebang position (buf+0 or buf+3) */
873 		cp = (unsigned char *)(buf + fd);
874 		/* bail out if read error (above) or no shebang */
875 		if ((cp[0] != '#') || (cp[1] != '!'))
876 			goto noshebang;
877 
878 		cp += 2;
879 		/* skip whitespace before shell name */
880 		while (*cp == ' ' || *cp == '\t')
881 			++cp;
882 		/* just whitespace on the line? */
883 		if (*cp == '\0')
884 			goto noshebang;
885 		/* no, we actually found an interpreter name */
886 		sh = (char *)cp;
887 		/* look for end of shell/interpreter name */
888 		while (*cp != ' ' && *cp != '\t' && *cp != '\0')
889 			++cp;
890 		/* any arguments? */
891 		if (*cp) {
892 			*cp++ = '\0';
893 			/* skip spaces before arguments */
894 			while (*cp == ' ' || *cp == '\t')
895 				++cp;
896 			/* pass it all in ONE argument (historic reasons) */
897 			if (*cp)
898 				*tp->args-- = (char *)cp;
899 		}
900  noshebang:
901 		fd = buf[0] << 8 | buf[1];
902 		if ((fd == /* OMAGIC */ 0407) ||
903 		    (fd == /* NMAGIC */ 0410) ||
904 		    (fd == /* ZMAGIC */ 0413) ||
905 		    (fd == /* QMAGIC */ 0314) ||
906 		    (fd == /* ECOFF_I386 */ 0x4C01) ||
907 		    (fd == /* ECOFF_M68K */ 0x0150 || fd == 0x5001) ||
908 		    (fd == /* ECOFF_SH */   0x0500 || fd == 0x0005) ||
909 		    (fd == 0x7F45 && buf[2] == 'L' && buf[3] == 'F') ||
910 		    (fd == /* "MZ" */ 0x4D5A) ||
911 		    (fd == /* gzip */ 0x1F8B))
912 			errorf("%s: not executable: magic %04X", tp->str, fd);
913 	}
914 #endif
915 	args.ro = tp->args;
916 	*args.ro = sh;
917 
918 	cap.ro = ap;
919 	execve(args.rw[0], args.rw, cap.rw);
920 
921 	/* report both the programme that was run and the bogus interpreter */
922 	errorf("%s: %s: %s", tp->str, sh, strerror(errno));
923 }
924 
925 int
shcomexec(const char ** wp)926 shcomexec(const char **wp)
927 {
928 	struct tbl *tp;
929 
930 	tp = ktsearch(&builtins, *wp, hash(*wp));
931 	if (tp == NULL)
932 		internal_errorf("%s: %s", "shcomexec", *wp);
933 	return (call_builtin(tp, wp));
934 }
935 
936 /*
937  * Search function tables for a function. If create set, a table entry
938  * is created if none is found.
939  */
940 struct tbl *
findfunc(const char * name,uint32_t h,bool create)941 findfunc(const char *name, uint32_t h, bool create)
942 {
943 	struct block *l;
944 	struct tbl *tp = NULL;
945 
946 	for (l = e->loc; l; l = l->next) {
947 		tp = ktsearch(&l->funs, name, h);
948 		if (tp)
949 			break;
950 		if (!l->next && create) {
951 			tp = ktenter(&l->funs, name, h);
952 			tp->flag = DEFINED;
953 			tp->type = CFUNC;
954 			tp->val.t = NULL;
955 			break;
956 		}
957 	}
958 	return (tp);
959 }
960 
961 /*
962  * define function. Returns 1 if function is being undefined (t == 0) and
963  * function did not exist, returns 0 otherwise.
964  */
965 int
define(const char * name,struct op * t)966 define(const char *name, struct op *t)
967 {
968 	uint32_t nhash;
969 	struct tbl *tp;
970 	bool was_set = false;
971 
972 	nhash = hash(name);
973 
974 	if (t != NULL && !tobool(t->u.ksh_func)) {
975 		/* drop same-name aliases for POSIX functions */
976 		if ((tp = ktsearch(&aliases, name, nhash)))
977 			ktdelete(tp);
978 	}
979 
980 	while (/* CONSTCOND */ 1) {
981 		tp = findfunc(name, nhash, true);
982 
983 		if (tp->flag & ISSET)
984 			was_set = true;
985 		/*
986 		 * If this function is currently being executed, we zap
987 		 * this table entry so findfunc() won't see it
988 		 */
989 		if (tp->flag & FINUSE) {
990 			tp->name[0] = '\0';
991 			/* ensure it won't be found */
992 			tp->flag &= ~DEFINED;
993 			tp->flag |= FDELETE;
994 		} else
995 			break;
996 	}
997 
998 	if (tp->flag & ALLOC) {
999 		tp->flag &= ~(ISSET|ALLOC);
1000 		tfree(tp->val.t, tp->areap);
1001 	}
1002 
1003 	if (t == NULL) {
1004 		/* undefine */
1005 		ktdelete(tp);
1006 		return (was_set ? 0 : 1);
1007 	}
1008 
1009 	tp->val.t = tcopy(t->left, tp->areap);
1010 	tp->flag |= (ISSET|ALLOC);
1011 	if (t->u.ksh_func)
1012 		tp->flag |= FKSH;
1013 
1014 	return (0);
1015 }
1016 
1017 /*
1018  * add builtin
1019  */
1020 const char *
builtin(const char * name,int (* func)(const char **))1021 builtin(const char *name, int (*func) (const char **))
1022 {
1023 	struct tbl *tp;
1024 	uint32_t flag;
1025 
1026 	/* see if any flags should be set for this builtin */
1027 	for (flag = 0; ; name++) {
1028 		if (*name == '=')
1029 			/* command does variable assignment */
1030 			flag |= KEEPASN;
1031 		else if (*name == '*')
1032 			/* POSIX special builtin */
1033 			flag |= SPEC_BI;
1034 		else if (*name == '+')
1035 			/* POSIX regular builtin */
1036 			flag |= REG_BI;
1037 		else
1038 			break;
1039 	}
1040 
1041 	tp = ktenter(&builtins, name, hash(name));
1042 	tp->flag = DEFINED | flag;
1043 	tp->type = CSHELL;
1044 	tp->val.f = func;
1045 
1046 	return (name);
1047 }
1048 
1049 /*
1050  * find command
1051  * either function, hashed command, or built-in (in that order)
1052  */
1053 struct tbl *
findcom(const char * name,int flags)1054 findcom(const char *name, int flags)
1055 {
1056 	static struct tbl temp;
1057 	uint32_t h = hash(name);
1058 	struct tbl *tp = NULL, *tbi;
1059 	/* insert if not found */
1060 	unsigned char insert = Flag(FTRACKALL);
1061 	/* for function autoloading */
1062 	char *fpath;
1063 	union mksh_cchack npath;
1064 
1065 	if (vstrchr(name, '/')) {
1066 		insert = 0;
1067 		/* prevent FPATH search below */
1068 		flags &= ~FC_FUNC;
1069 		goto Search;
1070 	}
1071 	tbi = (flags & FC_BI) ? ktsearch(&builtins, name, h) : NULL;
1072 	/*
1073 	 * POSIX says special builtins first, then functions, then
1074 	 * POSIX regular builtins, then search path...
1075 	 */
1076 	if ((flags & FC_SPECBI) && tbi && (tbi->flag & SPEC_BI))
1077 		tp = tbi;
1078 	if (!tp && (flags & FC_FUNC)) {
1079 		tp = findfunc(name, h, false);
1080 		if (tp && !(tp->flag & ISSET)) {
1081 			if ((fpath = str_val(global("FPATH"))) == null) {
1082 				tp->u.fpath = NULL;
1083 				tp->u2.errnov = ENOENT;
1084 			} else
1085 				tp->u.fpath = search_path(name, fpath, R_OK,
1086 				    &tp->u2.errnov);
1087 		}
1088 	}
1089 	if (!tp && (flags & FC_REGBI) && tbi && (tbi->flag & REG_BI))
1090 		tp = tbi;
1091 	if (!tp && (flags & FC_UNREGBI) && tbi)
1092 		tp = tbi;
1093 	if (!tp && (flags & FC_PATH) && !(flags & FC_DEFPATH)) {
1094 		tp = ktsearch(&taliases, name, h);
1095 		if (tp && (tp->flag & ISSET) &&
1096 		    ksh_access(tp->val.s, X_OK) != 0) {
1097 			if (tp->flag & ALLOC) {
1098 				tp->flag &= ~ALLOC;
1099 				afree(tp->val.s, APERM);
1100 			}
1101 			tp->flag &= ~ISSET;
1102 		}
1103 	}
1104 
1105  Search:
1106 	if ((!tp || (tp->type == CTALIAS && !(tp->flag&ISSET))) &&
1107 	    (flags & FC_PATH)) {
1108 		if (!tp) {
1109 			if (insert && !(flags & FC_DEFPATH)) {
1110 				tp = ktenter(&taliases, name, h);
1111 				tp->type = CTALIAS;
1112 			} else {
1113 				tp = &temp;
1114 				tp->type = CEXEC;
1115 			}
1116 			/* make ~ISSET */
1117 			tp->flag = DEFINED;
1118 		}
1119 		npath.ro = search_path(name,
1120 		    (flags & FC_DEFPATH) ? def_path : path,
1121 		    X_OK, &tp->u2.errnov);
1122 		if (npath.ro) {
1123 			strdupx(tp->val.s, npath.ro, APERM);
1124 			if (npath.ro != name)
1125 				afree(npath.rw, ATEMP);
1126 			tp->flag |= ISSET|ALLOC;
1127 		} else if ((flags & FC_FUNC) &&
1128 		    (fpath = str_val(global("FPATH"))) != null &&
1129 		    (npath.ro = search_path(name, fpath, R_OK,
1130 		    &tp->u2.errnov)) != NULL) {
1131 			/*
1132 			 * An undocumented feature of AT&T ksh is that
1133 			 * it searches FPATH if a command is not found,
1134 			 * even if the command hasn't been set up as an
1135 			 * autoloaded function (ie, no typeset -uf).
1136 			 */
1137 			tp = &temp;
1138 			tp->type = CFUNC;
1139 			/* make ~ISSET */
1140 			tp->flag = DEFINED;
1141 			tp->u.fpath = npath.ro;
1142 		}
1143 	}
1144 	return (tp);
1145 }
1146 
1147 /*
1148  * flush executable commands with relative paths
1149  * (just relative or all?)
1150  */
1151 void
flushcom(bool all)1152 flushcom(bool all)
1153 {
1154 	struct tbl *tp;
1155 	struct tstate ts;
1156 
1157 	for (ktwalk(&ts, &taliases); (tp = ktnext(&ts)) != NULL; )
1158 		if ((tp->flag&ISSET) && (all || tp->val.s[0] != '/')) {
1159 			if (tp->flag&ALLOC) {
1160 				tp->flag &= ~(ALLOC|ISSET);
1161 				afree(tp->val.s, APERM);
1162 			}
1163 			tp->flag &= ~ISSET;
1164 		}
1165 }
1166 
1167 /* check if path is something we want to find */
1168 static int
search_access(const char * fn,int mode)1169 search_access(const char *fn, int mode)
1170 {
1171 	struct stat sb;
1172 
1173 	if (stat(fn, &sb) < 0)
1174 		/* file does not exist */
1175 		return (ENOENT);
1176 	/* LINTED use of access */
1177 	if (access(fn, mode) < 0)
1178 		/* file exists, but we can't access it */
1179 		return (errno);
1180 	if (mode == X_OK && (!S_ISREG(sb.st_mode) ||
1181 	    !(sb.st_mode & (S_IXUSR|S_IXGRP|S_IXOTH))))
1182 		/* access(2) may say root can execute everything */
1183 		return (S_ISDIR(sb.st_mode) ? EISDIR : EACCES);
1184 	return (0);
1185 }
1186 
1187 /*
1188  * search for command with PATH
1189  */
1190 const char *
search_path(const char * name,const char * lpath,int mode,int * errnop)1191 search_path(const char *name, const char *lpath,
1192     /* R_OK or X_OK */
1193     int mode,
1194     /* set if candidate found, but not suitable */
1195     int *errnop)
1196 {
1197 	const char *sp, *p;
1198 	char *xp;
1199 	XString xs;
1200 	size_t namelen;
1201 	int ec = 0, ev;
1202 
1203 	if (vstrchr(name, '/')) {
1204 		if ((ec = search_access(name, mode)) == 0) {
1205  search_path_ok:
1206 			if (errnop)
1207 				*errnop = 0;
1208 			return (name);
1209 		}
1210 		goto search_path_err;
1211 	}
1212 
1213 	namelen = strlen(name) + 1;
1214 	Xinit(xs, xp, 128, ATEMP);
1215 
1216 	sp = lpath;
1217 	while (sp != NULL) {
1218 		xp = Xstring(xs, xp);
1219 		if (!(p = cstrchr(sp, ':')))
1220 			p = sp + strlen(sp);
1221 		if (p != sp) {
1222 			XcheckN(xs, xp, p - sp);
1223 			memcpy(xp, sp, p - sp);
1224 			xp += p - sp;
1225 			*xp++ = '/';
1226 		}
1227 		sp = p;
1228 		XcheckN(xs, xp, namelen);
1229 		memcpy(xp, name, namelen);
1230 		if ((ev = search_access(Xstring(xs, xp), mode)) == 0) {
1231 			name = Xclose(xs, xp + namelen);
1232 			goto search_path_ok;
1233 		}
1234 		/* accumulate non-ENOENT errors only */
1235 		if (ev != ENOENT && ec == 0)
1236 			ec = ev;
1237 		if (*sp++ == '\0')
1238 			sp = NULL;
1239 	}
1240 	Xfree(xs, xp);
1241  search_path_err:
1242 	if (errnop)
1243 		*errnop = ec ? ec : ENOENT;
1244 	return (NULL);
1245 }
1246 
1247 static int
call_builtin(struct tbl * tp,const char ** wp)1248 call_builtin(struct tbl *tp, const char **wp)
1249 {
1250 	int rv;
1251 
1252 	builtin_argv0 = wp[0];
1253 	builtin_flag = tp->flag;
1254 	shf_reopen(1, SHF_WR, shl_stdout);
1255 	shl_stdout_ok = true;
1256 	ksh_getopt_reset(&builtin_opt, GF_ERROR);
1257 	rv = (*tp->val.f)(wp);
1258 	shf_flush(shl_stdout);
1259 	shl_stdout_ok = false;
1260 	builtin_flag = 0;
1261 	builtin_argv0 = NULL;
1262 	return (rv);
1263 }
1264 
1265 /*
1266  * set up redirection, saving old fds in e->savefd
1267  */
1268 static int
iosetup(struct ioword * iop,struct tbl * tp)1269 iosetup(struct ioword *iop, struct tbl *tp)
1270 {
1271 	int u = -1;
1272 	char *cp = iop->name;
1273 	int iotype = iop->flag & IOTYPE;
1274 	int do_open = 1, do_close = 0, flags = 0;
1275 	struct ioword iotmp;
1276 	struct stat statb;
1277 
1278 	if (iotype != IOHERE)
1279 		cp = evalonestr(cp, DOTILDE|(Flag(FTALKING_I) ? DOGLOB : 0));
1280 
1281 	/* Used for tracing and error messages to print expanded cp */
1282 	iotmp = *iop;
1283 	iotmp.name = (iotype == IOHERE) ? NULL : cp;
1284 	iotmp.flag |= IONAMEXP;
1285 
1286 	if (Flag(FXTRACE))
1287 		shellf("%s%s\n",
1288 		    substitute(str_val(global("PS4")), 0),
1289 		    snptreef(NULL, 32, "%R", &iotmp));
1290 
1291 	switch (iotype) {
1292 	case IOREAD:
1293 		flags = O_RDONLY;
1294 		break;
1295 
1296 	case IOCAT:
1297 		flags = O_WRONLY | O_APPEND | O_CREAT;
1298 		break;
1299 
1300 	case IOWRITE:
1301 		flags = O_WRONLY | O_CREAT | O_TRUNC;
1302 		/*
1303 		 * The stat() is here to allow redirections to
1304 		 * things like /dev/null without error.
1305 		 */
1306 		if (Flag(FNOCLOBBER) && !(iop->flag & IOCLOB) &&
1307 		    (stat(cp, &statb) < 0 || S_ISREG(statb.st_mode)))
1308 			flags |= O_EXCL;
1309 		break;
1310 
1311 	case IORDWR:
1312 		flags = O_RDWR | O_CREAT;
1313 		break;
1314 
1315 	case IOHERE:
1316 		do_open = 0;
1317 		/* herein() returns -2 if error has been printed */
1318 		u = herein(iop->heredoc, iop->flag & IOEVAL, NULL);
1319 		/* cp may have wrong name */
1320 		break;
1321 
1322 	case IODUP: {
1323 		const char *emsg;
1324 
1325 		do_open = 0;
1326 		if (*cp == '-' && !cp[1]) {
1327 			/* prevent error return below */
1328 			u = 1009;
1329 			do_close = 1;
1330 		} else if ((u = check_fd(cp,
1331 		    X_OK | ((iop->flag & IORDUP) ? R_OK : W_OK),
1332 		    &emsg)) < 0) {
1333 			warningf(true, "%s: %s",
1334 			    snptreef(NULL, 32, "%R", &iotmp), emsg);
1335 			return (-1);
1336 		}
1337 		if (u == iop->unit)
1338 			/* "dup from" == "dup to" */
1339 			return (0);
1340 		break;
1341 	}
1342 	}
1343 
1344 	if (do_open) {
1345 		if (Flag(FRESTRICTED) && (flags & O_CREAT)) {
1346 			warningf(true, "%s: %s", cp, "restricted");
1347 			return (-1);
1348 		}
1349 		u = open(cp, flags, 0666);
1350 	}
1351 	if (u < 0) {
1352 		/* herein() may already have printed message */
1353 		if (u == -1) {
1354 			u = errno;
1355 			warningf(true, "can't %s %s: %s",
1356 			    iotype == IODUP ? "dup" :
1357 			    (iotype == IOREAD || iotype == IOHERE) ?
1358 			    "open" : "create", cp, strerror(u));
1359 		}
1360 		return (-1);
1361 	}
1362 	/* Do not save if it has already been redirected (i.e. "cat >x >y"). */
1363 	if (e->savefd[iop->unit] == 0) {
1364 		/* If these are the same, it means unit was previously closed */
1365 		if (u == iop->unit)
1366 			e->savefd[iop->unit] = -1;
1367 		else
1368 			/*
1369 			 * c_exec() assumes e->savefd[fd] set for any
1370 			 * redirections. Ask savefd() not to close iop->unit;
1371 			 * this allows error messages to be seen if iop->unit
1372 			 * is 2; also means we can't lose the fd (eg, both
1373 			 * dup2 below and dup2 in restfd() failing).
1374 			 */
1375 			e->savefd[iop->unit] = savefd(iop->unit);
1376 	}
1377 
1378 	if (do_close)
1379 		close(iop->unit);
1380 	else if (u != iop->unit) {
1381 		if (ksh_dup2(u, iop->unit, true) < 0) {
1382 			int ev;
1383 
1384 			ev = errno;
1385 			warningf(true, "%s %s %s",
1386 			    "can't finish (dup) redirection",
1387 			    snptreef(NULL, 32, "%R", &iotmp),
1388 			    strerror(ev));
1389 			if (iotype != IODUP)
1390 				close(u);
1391 			return (-1);
1392 		}
1393 		if (iotype != IODUP)
1394 			close(u);
1395 		/*
1396 		 * Touching any co-process fd in an empty exec
1397 		 * causes the shell to close its copies
1398 		 */
1399 		else if (tp && tp->type == CSHELL && tp->val.f == c_exec) {
1400 			if (iop->flag & IORDUP)
1401 				/* possible exec <&p */
1402 				coproc_read_close(u);
1403 			else
1404 				/* possible exec >&p */
1405 				coproc_write_close(u);
1406 		}
1407 	}
1408 	if (u == 2)
1409 		/* Clear any write errors */
1410 		shf_reopen(2, SHF_WR, shl_out);
1411 	return (0);
1412 }
1413 
1414 /*
1415  * Process here documents by providing the content, either as
1416  * result (globally allocated) string or in a temp file; if
1417  * unquoted, the string is expanded first.
1418  */
1419 static int
hereinval(const char * content,int sub,char ** resbuf,struct shf * shf)1420 hereinval(const char *content, int sub, char **resbuf, struct shf *shf)
1421 {
1422 	const char *ccp;
1423 	struct source *s, *osource;
1424 
1425 	osource = source;
1426 	newenv(E_ERRH);
1427 	if (sigsetjmp(e->jbuf, 0)) {
1428 		source = osource;
1429 		quitenv(shf);
1430 		/* special to iosetup(): don't print error */
1431 		return (-2);
1432 	}
1433 	if (sub) {
1434 		/* do substitutions on the content of heredoc */
1435 		s = pushs(SSTRING, ATEMP);
1436 		s->start = s->str = content;
1437 		source = s;
1438 		if (yylex(ONEWORD|HEREDOC) != LWORD)
1439 			internal_errorf("%s: %s", "herein", "yylex");
1440 		source = osource;
1441 		ccp = evalstr(yylval.cp, 0);
1442 	} else
1443 		ccp = content;
1444 
1445 	if (resbuf == NULL)
1446 		shf_puts(ccp, shf);
1447 	else
1448 		strdupx(*resbuf, ccp, APERM);
1449 
1450 	quitenv(NULL);
1451 	return (0);
1452 }
1453 
1454 static int
herein(const char * content,int sub,char ** resbuf)1455 herein(const char *content, int sub, char **resbuf)
1456 {
1457 	int fd = -1;
1458 	struct shf *shf;
1459 	struct temp *h;
1460 	int i;
1461 
1462 	/* ksh -c 'cat << EOF' can cause this... */
1463 	if (content == NULL) {
1464 		warningf(true, "%s missing", "here document");
1465 		/* special to iosetup(): don't print error */
1466 		return (-2);
1467 	}
1468 
1469 	/* skip all the fd setup if we just want the value */
1470 	if (resbuf != NULL)
1471 		return (hereinval(content, sub, resbuf, NULL));
1472 
1473 	/*
1474 	 * Create temp file to hold content (done before newenv
1475 	 * so temp doesn't get removed too soon).
1476 	 */
1477 	h = maketemp(ATEMP, TT_HEREDOC_EXP, &e->temps);
1478 	if (!(shf = h->shf) || (fd = open(h->name, O_RDONLY, 0)) < 0) {
1479 		i = errno;
1480 		warningf(true, "can't %s temporary file %s: %s",
1481 		    !shf ? "create" : "open", h->name, strerror(i));
1482 		if (shf)
1483 			shf_close(shf);
1484 		/* special to iosetup(): don't print error */
1485 		return (-2);
1486 	}
1487 
1488 	if (hereinval(content, sub, NULL, shf) == -2) {
1489 		close(fd);
1490 		/* special to iosetup(): don't print error */
1491 		return (-2);
1492 	}
1493 
1494 	if (shf_close(shf) == EOF) {
1495 		i = errno;
1496 		close(fd);
1497 		warningf(true, "%s: %s: %s", "write", h->name, strerror(i));
1498 		/* special to iosetup(): don't print error */
1499 		return (-2);
1500 	}
1501 
1502 	return (fd);
1503 }
1504 
1505 /*
1506  *	ksh special - the select command processing section
1507  *	print the args in column form - assuming that we can
1508  */
1509 static const char *
do_selectargs(const char ** ap,bool print_menu)1510 do_selectargs(const char **ap, bool print_menu)
1511 {
1512 	static const char *read_args[] = {
1513 		"read", "-r", "REPLY", NULL
1514 	};
1515 	char *s;
1516 	int i, argct;
1517 
1518 	for (argct = 0; ap[argct]; argct++)
1519 		;
1520 	while (/* CONSTCOND */ 1) {
1521 		/*-
1522 		 * Menu is printed if
1523 		 *	- this is the first time around the select loop
1524 		 *	- the user enters a blank line
1525 		 *	- the REPLY parameter is empty
1526 		 */
1527 		if (print_menu || !*str_val(global("REPLY")))
1528 			pr_menu(ap);
1529 		shellf("%s", str_val(global("PS3")));
1530 		if (call_builtin(findcom("read", FC_BI), read_args))
1531 			return (NULL);
1532 		s = str_val(global("REPLY"));
1533 		if (*s) {
1534 			getn(s, &i);
1535 			return ((i >= 1 && i <= argct) ? ap[i - 1] : null);
1536 		}
1537 		print_menu = 1;
1538 	}
1539 }
1540 
1541 struct select_menu_info {
1542 	const char * const *args;
1543 	int num_width;
1544 };
1545 
1546 static char *select_fmt_entry(char *, size_t, int, const void *);
1547 
1548 /* format a single select menu item */
1549 static char *
select_fmt_entry(char * buf,size_t buflen,int i,const void * arg)1550 select_fmt_entry(char *buf, size_t buflen, int i, const void *arg)
1551 {
1552 	const struct select_menu_info *smi =
1553 	    (const struct select_menu_info *)arg;
1554 
1555 	shf_snprintf(buf, buflen, "%*d) %s",
1556 	    smi->num_width, i + 1, smi->args[i]);
1557 	return (buf);
1558 }
1559 
1560 /*
1561  *	print a select style menu
1562  */
1563 int
pr_menu(const char * const * ap)1564 pr_menu(const char * const *ap)
1565 {
1566 	struct select_menu_info smi;
1567 	const char * const *pp;
1568 	size_t acols = 0, aocts = 0, i;
1569 	int n;
1570 
1571 	/*
1572 	 * width/column calculations were done once and saved, but this
1573 	 * means select can't be used recursively so we re-calculate
1574 	 * each time (could save in a structure that is returned, but
1575 	 * it's probably not worth the bother)
1576 	 */
1577 
1578 	/*
1579 	 * get dimensions of the list
1580 	 */
1581 	for (n = 0, pp = ap; *pp; n++, pp++) {
1582 		i = strlen(*pp);
1583 		if (i > aocts)
1584 			aocts = i;
1585 		i = utf_mbswidth(*pp);
1586 		if (i > acols)
1587 			acols = i;
1588 	}
1589 
1590 	/*
1591 	 * we will print an index of the form "%d) " in front of
1592 	 * each entry, so get the maximum width of this
1593 	 */
1594 	for (i = n, smi.num_width = 1; i >= 10; i /= 10)
1595 		smi.num_width++;
1596 
1597 	smi.args = ap;
1598 	print_columns(shl_out, n, select_fmt_entry, (void *)&smi,
1599 	    smi.num_width + 2 + aocts, smi.num_width + 2 + acols,
1600 	    true);
1601 
1602 	return (n);
1603 }
1604 
1605 /* XXX: horrible kludge to fit within the framework */
1606 static char *plain_fmt_entry(char *, size_t, int, const void *);
1607 
1608 static char *
plain_fmt_entry(char * buf,size_t buflen,int i,const void * arg)1609 plain_fmt_entry(char *buf, size_t buflen, int i, const void *arg)
1610 {
1611 	strlcpy(buf, ((const char * const *)arg)[i], buflen);
1612 	return (buf);
1613 }
1614 
1615 int
pr_list(char * const * ap)1616 pr_list(char * const *ap)
1617 {
1618 	size_t acols = 0, aocts = 0, i;
1619 	int n;
1620 	char * const *pp;
1621 
1622 	for (n = 0, pp = ap; *pp; n++, pp++) {
1623 		i = strlen(*pp);
1624 		if (i > aocts)
1625 			aocts = i;
1626 		i = utf_mbswidth(*pp);
1627 		if (i > acols)
1628 			acols = i;
1629 	}
1630 
1631 	print_columns(shl_out, n, plain_fmt_entry, (const void *)ap,
1632 	    aocts, acols, false);
1633 
1634 	return (n);
1635 }
1636 
1637 /*
1638  *	[[ ... ]] evaluation routines
1639  */
1640 
1641 /*
1642  * Test if the current token is a whatever. Accepts the current token if
1643  * it is. Returns 0 if it is not, non-zero if it is (in the case of
1644  * TM_UNOP and TM_BINOP, the returned value is a Test_op).
1645  */
1646 static Test_op
dbteste_isa(Test_env * te,Test_meta meta)1647 dbteste_isa(Test_env *te, Test_meta meta)
1648 {
1649 	Test_op ret = TO_NONOP;
1650 	int uqword;
1651 	const char *p;
1652 
1653 	if (!*te->pos.wp)
1654 		return (meta == TM_END ? TO_NONNULL : TO_NONOP);
1655 
1656 	/* unquoted word? */
1657 	for (p = *te->pos.wp; *p == CHAR; p += 2)
1658 		;
1659 	uqword = *p == EOS;
1660 
1661 	if (meta == TM_UNOP || meta == TM_BINOP) {
1662 		if (uqword) {
1663 			/* longer than the longest operator */
1664 			char buf[8];
1665 			char *q = buf;
1666 
1667 			for (p = *te->pos.wp;
1668 			    *p == CHAR && q < &buf[sizeof(buf) - 1]; p += 2)
1669 				*q++ = p[1];
1670 			*q = '\0';
1671 			ret = test_isop(meta, buf);
1672 		}
1673 	} else if (meta == TM_END)
1674 		ret = TO_NONOP;
1675 	else
1676 		ret = (uqword && !strcmp(*te->pos.wp,
1677 		    dbtest_tokens[(int)meta])) ? TO_NONNULL : TO_NONOP;
1678 
1679 	/* Accept the token? */
1680 	if (ret != TO_NONOP)
1681 		te->pos.wp++;
1682 
1683 	return (ret);
1684 }
1685 
1686 static const char *
dbteste_getopnd(Test_env * te,Test_op op,bool do_eval)1687 dbteste_getopnd(Test_env *te, Test_op op, bool do_eval)
1688 {
1689 	const char *s = *te->pos.wp;
1690 
1691 	if (!s)
1692 		return (NULL);
1693 
1694 	te->pos.wp++;
1695 
1696 	if (!do_eval)
1697 		return (null);
1698 
1699 	if (op == TO_STEQL || op == TO_STNEQ)
1700 		s = evalstr(s, DOTILDE | DOPAT);
1701 	else
1702 		s = evalstr(s, DOTILDE);
1703 
1704 	return (s);
1705 }
1706 
1707 static void
dbteste_error(Test_env * te,int offset,const char * msg)1708 dbteste_error(Test_env *te, int offset, const char *msg)
1709 {
1710 	te->flags |= TEF_ERROR;
1711 	internal_warningf("dbteste_error: %s (offset %d)", msg, offset);
1712 }
1713