xref: /netbsd-src/bin/ksh/exec.c (revision 23c8222edbfb0f0932d88a8351d3a0cf817dfb9e)
1 /*	$NetBSD: exec.c,v 1.9 2004/07/07 19:20:09 mycroft Exp $	*/
2 
3 /*
4  * execute command tree
5  */
6 #include <sys/cdefs.h>
7 
8 #ifndef lint
9 __RCSID("$NetBSD: exec.c,v 1.9 2004/07/07 19:20:09 mycroft Exp $");
10 #endif
11 
12 
13 #include "sh.h"
14 #include "c_test.h"
15 #include <ctype.h>
16 #include "ksh_stat.h"
17 
18 /* Does ps4 get parameter substitutions done? */
19 #ifdef KSH
20 # define PS4_SUBSTITUTE(s)	substitute((s), 0)
21 #else
22 # define PS4_SUBSTITUTE(s)	(s)
23 #endif /* KSH */
24 
25 static int	comexec	 ARGS((struct op *t, struct tbl *volatile tp, char **ap,
26 			      int volatile flags));
27 static void	scriptexec ARGS((struct op *tp, char **ap));
28 static int	call_builtin ARGS((struct tbl *tp, char **wp));
29 static int	iosetup ARGS((struct ioword *iop, struct tbl *tp));
30 static int	herein ARGS((const char *content, int sub));
31 #ifdef KSH
32 static char 	*do_selectargs ARGS((char **ap, bool_t print_menu));
33 #endif /* KSH */
34 #ifdef KSH
35 static int	dbteste_isa ARGS((Test_env *te, Test_meta meta));
36 static const char *dbteste_getopnd ARGS((Test_env *te, Test_op op,
37 					 int do_eval));
38 static int	dbteste_eval ARGS((Test_env *te, Test_op op, const char *opnd1,
39 				const char *opnd2, int do_eval));
40 static void	dbteste_error ARGS((Test_env *te, int offset, const char *msg));
41 #endif /* KSH */
42 #ifdef OS2
43 static int	search_access1 ARGS((const char *path, int mode, int *errnop));
44 #endif /* OS2 */
45 
46 
47 /*
48  * handle systems that don't have F_SETFD
49  */
50 #ifndef F_SETFD
51 # ifndef MAXFD
52 #   define  MAXFD 64
53 # endif
54 /* a bit field would be smaller, but this will work */
55 static char clexec_tab[MAXFD+1];
56 #endif
57 
58 /*
59  * we now use this function always.
60  */
61 int
62 fd_clexec(fd)
63     int fd;
64 {
65 #ifndef F_SETFD
66 	if (fd >= 0 && fd < sizeof(clexec_tab)) {
67 		clexec_tab[fd] = 1;
68 		return 0;
69 	}
70 	return -1;
71 #else
72 	return fcntl(fd, F_SETFD, 1);
73 #endif
74 }
75 
76 
77 /*
78  * execute command tree
79  */
80 int
81 execute(t, flags)
82 	struct op * volatile t;
83 	volatile int flags;	/* if XEXEC don't fork */
84 {
85 	int i;
86 	volatile int rv = 0;
87 	int pv[2];
88 	char ** volatile ap;
89 	char *s, *cp;
90 	struct ioword **iowp;
91 	struct tbl *tp = NULL;
92 
93 	if (t == NULL)
94 		return 0;
95 
96 	/* Is this the end of a pipeline?  If so, we want to evaluate the
97 	 * command arguments
98 	bool_t eval_done = FALSE;
99 	if ((flags&XFORK) && !(flags&XEXEC) && (flags&XPCLOSE)) {
100 		eval_done = TRUE;
101 		tp = eval_execute_args(t, &ap);
102 	}
103 	 */
104 	if ((flags&XFORK) && !(flags&XEXEC) && t->type != TPIPE)
105 		return exchild(t, flags & ~XTIME, -1); /* run in sub-process */
106 
107 	newenv(E_EXEC);
108 	if (trap)
109 		runtraps(0);
110 
111 	if (t->type == TCOM) {
112 		/* Clear subst_exstat before argument expansion.  Used by
113 		 * null commands (see comexec() and c_eval()) and by c_set().
114 		 */
115 		subst_exstat = 0;
116 
117 		current_lineno = t->lineno;	/* for $LINENO */
118 
119 		/* POSIX says expand command words first, then redirections,
120 		 * and assignments last..
121 		 */
122 		ap = eval(t->args, t->u.evalflags | DOBLANK | DOGLOB | DOTILDE);
123 		if (flags & XTIME)
124 			/* Allow option parsing (bizarre, but POSIX) */
125 			timex_hook(t, &ap);
126 		if (Flag(FXTRACE) && ap[0]) {
127 			shf_fprintf(shl_out, "%s",
128 				PS4_SUBSTITUTE(str_val(global("PS4"))));
129 			for (i = 0; ap[i]; i++)
130 				shf_fprintf(shl_out, "%s%s", ap[i],
131 					ap[i + 1] ? space : newline);
132 			shf_flush(shl_out);
133 		}
134 		if (ap[0])
135 			tp = findcom(ap[0], FC_BI|FC_FUNC);
136 	}
137 	flags &= ~XTIME;
138 
139 	if (t->ioact != NULL || t->type == TPIPE || t->type == TCOPROC) {
140 		e->savefd = (short *) alloc(sizeofN(short, NUFILE), ATEMP);
141 		/* initialize to not redirected */
142 		memset(e->savefd, 0, sizeofN(short, NUFILE));
143 	}
144 
145 	/* do redirection, to be restored in quitenv() */
146 	if (t->ioact != NULL)
147 		for (iowp = t->ioact; *iowp != NULL; iowp++) {
148 			if (iosetup(*iowp, tp) < 0) {
149 				exstat = rv = 1;
150 				/* Redirection failures for special commands
151 				 * cause (non-interactive) shell to exit.
152 				 */
153 				if (tp && tp->type == CSHELL
154 				    && (tp->flag & SPEC_BI))
155 					errorf(null);
156 				/* Deal with FERREXIT, quitenv(), etc. */
157 				goto Break;
158 			}
159 		}
160 
161 	switch(t->type) {
162 	  case TCOM:
163 		rv = comexec(t, tp, ap, flags);
164 		break;
165 
166 	  case TPAREN:
167 		rv = execute(t->left, flags|XFORK);
168 		break;
169 
170 	  case TPIPE:
171 		flags |= XFORK;
172 		flags &= ~XEXEC;
173 		e->savefd[0] = savefd(0, 0);
174 		(void) ksh_dup2(e->savefd[0], 0, FALSE); /* stdin of first */
175 		e->savefd[1] = savefd(1, 0);
176 		while (t->type == TPIPE) {
177 			openpipe(pv);
178 			(void) ksh_dup2(pv[1], 1, FALSE); /* stdout of curr */
179 			/* Let exchild() close pv[0] in child
180 			 * (if this isn't done, commands like
181 			 *    (: ; cat /etc/termcap) | sleep 1
182 			 *  will hang forever).
183 			 */
184 			exchild(t->left, flags|XPIPEO|XCCLOSE, pv[0]);
185 			(void) ksh_dup2(pv[0], 0, FALSE); /* stdin of next */
186 			closepipe(pv);
187 			flags |= XPIPEI;
188 			t = t->right;
189 		}
190 		restfd(1, e->savefd[1]); /* stdout of last */
191 		e->savefd[1] = 0; /* no need to re-restore this */
192 		/* Let exchild() close 0 in parent, after fork, before wait */
193 		i = exchild(t, flags|XPCLOSE, 0);
194 		if (!(flags&XBGND) && !(flags&XXCOM))
195 			rv = i;
196 		break;
197 
198 	  case TLIST:
199 		while (t->type == TLIST) {
200 			execute(t->left, flags & XERROK);
201 			t = t->right;
202 		}
203 		rv = execute(t, flags & XERROK);
204 		break;
205 
206 #ifdef KSH
207 	  case TCOPROC:
208 	  {
209 # ifdef JOB_SIGS
210 		sigset_t	omask;
211 # endif /* JOB_SIGS */
212 
213 # ifdef JOB_SIGS
214 		/* Block sigchild as we are using things changed in the
215 		 * signal handler
216 		 */
217 		sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
218 		e->type = E_ERRH;
219 		i = ksh_sigsetjmp(e->jbuf, 0);
220 		if (i) {
221 			sigprocmask(SIG_SETMASK, &omask, (sigset_t *) 0);
222 			quitenv();
223 			unwind(i);
224 			/*NOTREACHED*/
225 		}
226 # endif /* JOB_SIGS */
227 		/* Already have a (live) co-process? */
228 		if (coproc.job && coproc.write >= 0)
229 			errorf("coprocess already exists");
230 
231 		/* Can we re-use the existing co-process pipe? */
232 		coproc_cleanup(TRUE);
233 
234 		/* do this before opening pipes, in case these fail */
235 		e->savefd[0] = savefd(0, 0);
236 		e->savefd[1] = savefd(1, 0);
237 
238 		openpipe(pv);
239 		if (pv[0] != 0) {
240 			ksh_dup2(pv[0], 0, FALSE);
241 			close(pv[0]);
242 		}
243 		coproc.write = pv[1];
244 		coproc.job = (void *) 0;
245 
246 		if (coproc.readw >= 0)
247 			ksh_dup2(coproc.readw, 1, FALSE);
248 		else {
249 			openpipe(pv);
250 			coproc.read = pv[0];
251 			ksh_dup2(pv[1], 1, FALSE);
252 			coproc.readw = pv[1];	 /* closed before first read */
253 			coproc.njobs = 0;
254 			/* create new coprocess id */
255 			++coproc.id;
256 		}
257 # ifdef JOB_SIGS
258 		sigprocmask(SIG_SETMASK, &omask, (sigset_t *) 0);
259 		e->type = E_EXEC; /* no more need for error handler */
260 # endif /* JOB_SIGS */
261 
262 		/* exchild() closes coproc.* in child after fork,
263 		 * will also increment coproc.njobs when the
264 		 * job is actually created.
265 		 */
266 		flags &= ~XEXEC;
267 		exchild(t->left, flags|XBGND|XFORK|XCOPROC|XCCLOSE,
268 			coproc.readw);
269 		break;
270 	  }
271 #endif /* KSH */
272 
273 	  case TASYNC:
274 		/* XXX non-optimal, I think - "(foo &)", forks for (),
275 		 * forks again for async...  parent should optimize
276 		 * this to "foo &"...
277 		 */
278 		rv = execute(t->left, (flags&~XEXEC)|XBGND|XFORK);
279 		break;
280 
281 	  case TOR:
282 	  case TAND:
283 		rv = execute(t->left, XERROK);
284 		if (t->right != NULL && (rv == 0) == (t->type == TAND))
285 			rv = execute(t->right, flags & XERROK);
286 		else
287 			flags |= XERROK;
288 		break;
289 
290 	  case TBANG:
291 		rv = !execute(t->right, XERROK);
292 		break;
293 
294 #ifdef KSH
295 	  case TDBRACKET:
296 	    {
297 		Test_env te;
298 
299 		te.flags = TEF_DBRACKET;
300 		te.pos.wp = t->args;
301 		te.isa = dbteste_isa;
302 		te.getopnd = dbteste_getopnd;
303 		te.eval = dbteste_eval;
304 		te.error = dbteste_error;
305 
306 		rv = test_parse(&te);
307 		break;
308 	    }
309 #endif /* KSH */
310 
311 	  case TFOR:
312 #ifdef KSH
313 	  case TSELECT:
314 	    {
315 		volatile bool_t is_first = TRUE;
316 #endif /* KSH */
317 		ap = (t->vars != NULL) ?
318 			  eval(t->vars, DOBLANK|DOGLOB|DOTILDE)
319 			: e->loc->argv + 1;
320 		e->type = E_LOOP;
321 		while (1) {
322 			i = ksh_sigsetjmp(e->jbuf, 0);
323 			if (!i)
324 				break;
325 			if ((e->flags&EF_BRKCONT_PASS)
326 			    || (i != LBREAK && i != LCONTIN))
327 			{
328 				quitenv();
329 				unwind(i);
330 			} else if (i == LBREAK) {
331 				rv = 0;
332 				goto Break;
333 			}
334 		}
335 		rv = 0; /* in case of a continue */
336 		if (t->type == TFOR) {
337 			while (*ap != NULL) {
338 				setstr(global(t->str), *ap++, KSH_UNWIND_ERROR);
339 				rv = execute(t->left, flags & XERROK);
340 			}
341 		}
342 #ifdef KSH
343 		else { /* TSELECT */
344 			for (;;) {
345 				if (!(cp = do_selectargs(ap, is_first))) {
346 					rv = 1;
347 					break;
348 				}
349 				is_first = FALSE;
350 				setstr(global(t->str), cp, KSH_UNWIND_ERROR);
351 				rv = execute(t->left, flags & XERROK);
352 			}
353 		}
354 	    }
355 #endif /* KSH */
356 		break;
357 
358 	  case TWHILE:
359 	  case TUNTIL:
360 		e->type = E_LOOP;
361 		while (1) {
362 			i = ksh_sigsetjmp(e->jbuf, 0);
363 			if (!i)
364 				break;
365 			if ((e->flags&EF_BRKCONT_PASS)
366 			    || (i != LBREAK && i != LCONTIN))
367 			{
368 				quitenv();
369 				unwind(i);
370 			} else if (i == LBREAK) {
371 				rv = 0;
372 				goto Break;
373 			}
374 		}
375 		rv = 0; /* in case of a continue */
376 		while ((execute(t->left, XERROK) == 0) == (t->type == TWHILE))
377 			rv = execute(t->right, flags & XERROK);
378 		break;
379 
380 	  case TIF:
381 	  case TELIF:
382 		if (t->right == NULL)
383 			break;	/* should be error */
384 		rv = execute(t->left, XERROK) == 0 ?
385 			execute(t->right->left, flags & XERROK) :
386 			execute(t->right->right, flags & XERROK);
387 		break;
388 
389 	  case TCASE:
390 		cp = evalstr(t->str, DOTILDE);
391 		for (t = t->left; t != NULL && t->type == TPAT; t = t->right)
392 		    for (ap = t->vars; *ap; ap++)
393 			if ((s = evalstr(*ap, DOTILDE|DOPAT))
394 			    && gmatch(cp, s, FALSE))
395 				goto Found;
396 		break;
397 	  Found:
398 		rv = execute(t->left, flags & XERROK);
399 		break;
400 
401 	  case TBRACE:
402 		rv = execute(t->left, flags & XERROK);
403 		break;
404 
405 	  case TFUNCT:
406 		rv = define(t->str, t);
407 		break;
408 
409 	  case TTIME:
410 		/* Clear XEXEC so nested execute() call doesn't exit
411 		 * (allows "ls -l | time grep foo").
412 		 */
413 		rv = timex(t, flags & ~XEXEC);
414 		break;
415 
416 	  case TEXEC:		/* an eval'd TCOM */
417 		s = t->args[0];
418 		ap = makenv();
419 #ifndef F_SETFD
420 		for (i = 0; i < sizeof(clexec_tab); i++)
421 			if (clexec_tab[i]) {
422 				close(i);
423 				clexec_tab[i] = 0;
424 			}
425 #endif
426 		restoresigs();
427 		cleanup_proc_env();
428 		/* XINTACT bit is for OS2 */
429 		ksh_execve(t->str, t->args, ap, (flags & XINTACT) ? 1 : 0);
430 		if (errno == ENOEXEC)
431 			scriptexec(t, ap);
432 		else
433 			errorf("%s: %s", s, strerror(errno));
434 	}
435     Break:
436 	exstat = rv;
437 
438 	quitenv();		/* restores IO */
439 	if ((flags&XEXEC))
440 		unwind(LEXIT);	/* exit child */
441 	if (rv != 0 && !(flags & XERROK)) {
442 		if (Flag(FERREXIT))
443 			unwind(LERROR);
444 		trapsig(SIGERR_);
445 	}
446 	return rv;
447 }
448 
449 /*
450  * execute simple command
451  */
452 
453 static int
454 comexec(t, tp, ap, flags)
455 	struct op *t;
456 	struct tbl *volatile tp;
457 	register char **ap;
458 	int volatile flags;
459 {
460 	int i;
461 	volatile int rv = 0;
462 	register char *cp;
463 	register char **lastp;
464 	static struct op texec; /* Must be static (XXX but why?) */
465 	int type_flags;
466 	int keepasn_ok;
467 	int fcflags = FC_BI|FC_FUNC|FC_PATH;
468 	int bourne_function_call = 0;
469 
470 #ifdef KSH
471 	/* snag the last argument for $_ XXX not the same as at&t ksh,
472 	 * which only seems to set $_ after a newline (but not in
473 	 * functions/dot scripts, but in interactive and script) -
474 	 * perhaps save last arg here and set it in shell()?.
475 	 */
476 	if (Flag(FTALKING) && *(lastp = ap)) {
477 		while (*++lastp)
478 			;
479 		/* setstr() can't fail here */
480 		setstr(typeset("_", LOCAL, 0, INTEGER, 0), *--lastp,
481 		       KSH_RETURN_ERROR);
482 	}
483 #endif /* KSH */
484 
485 	/* Deal with the shell builtins builtin, exec and command since
486 	 * they can be followed by other commands.  This must be done before
487 	 * we know if we should create a local block, which must be done
488 	 * before we can do a path search (in case the assignments change
489 	 * PATH).
490 	 * Odd cases:
491 	 *   FOO=bar exec > /dev/null		FOO is kept but not exported
492 	 *   FOO=bar exec foobar		FOO is exported
493 	 *   FOO=bar command exec > /dev/null	FOO is neither kept nor exported
494 	 *   FOO=bar command			FOO is neither kept nor exported
495 	 *   PATH=... foobar			use new PATH in foobar search
496 	 */
497 	keepasn_ok = 1;
498 	while (tp && tp->type == CSHELL) {
499 		fcflags = FC_BI|FC_FUNC|FC_PATH;/* undo effects of command */
500 		if (tp->val.f == c_builtin) {
501 			if ((cp = *++ap) == NULL) {
502 				tp = NULL;
503 				break;
504 			}
505 			tp = findcom(cp, FC_BI);
506 			if (tp == NULL)
507 				errorf("builtin: %s: not a builtin", cp);
508 			continue;
509 		} else if (tp->val.f == c_exec) {
510 			if (ap[1] == NULL)
511 				break;
512 			ap++;
513 			flags |= XEXEC;
514 		} else if (tp->val.f == c_command) {
515 			int optc, saw_p = 0;
516 
517 			/* Ugly dealing with options in two places (here and
518 			 * in c_command(), but such is life)
519 			 */
520 			ksh_getopt_reset(&builtin_opt, 0);
521 			while ((optc = ksh_getopt(ap, &builtin_opt, ":p"))
522 									== 'p')
523 				saw_p = 1;
524 			if (optc != EOF)
525 				break;	/* command -vV or something */
526 			/* don't look for functions */
527 			fcflags = FC_BI|FC_PATH;
528 			if (saw_p) {
529 				if (Flag(FRESTRICTED)) {
530 					warningf(TRUE,
531 						"command -p: restricted");
532 					rv = 1;
533 					goto Leave;
534 				}
535 				fcflags |= FC_DEFPATH;
536 			}
537 			ap += builtin_opt.optind;
538 			/* POSIX says special builtins lose their status
539 			 * if accessed using command.
540 			 */
541 			keepasn_ok = 0;
542 			if (!ap[0]) {
543 				/* ensure command with no args exits with 0 */
544 				subst_exstat = 0;
545 				break;
546 			}
547 		} else
548 			break;
549 		tp = findcom(ap[0], fcflags & (FC_BI|FC_FUNC));
550 	}
551 	if (keepasn_ok && (!ap[0] || (tp && (tp->flag & KEEPASN))))
552 		type_flags = 0;
553 	else {
554 		/* create new variable/function block */
555 		newblock();
556 		/* ksh functions don't keep assignments, POSIX functions do. */
557 		if (keepasn_ok && tp && tp->type == CFUNC
558 		    && !(tp->flag & FKSH)) {
559 			bourne_function_call = 1;
560 			type_flags = 0;
561 		} else
562 			type_flags = LOCAL|LOCAL_COPY|EXPORT;
563 	}
564 	if (Flag(FEXPORT))
565 		type_flags |= EXPORT;
566 	for (i = 0; t->vars[i]; i++) {
567 		cp = evalstr(t->vars[i], DOASNTILDE);
568 		if (Flag(FXTRACE)) {
569 			if (i == 0)
570 				shf_fprintf(shl_out, "%s",
571 					PS4_SUBSTITUTE(str_val(global("PS4"))));
572 			shf_fprintf(shl_out, "%s%s", cp,
573 				t->vars[i + 1] ? space : newline);
574 			if (!t->vars[i + 1])
575 				shf_flush(shl_out);
576 		}
577 		typeset(cp, type_flags, 0, 0, 0);
578 		if (bourne_function_call && !(type_flags & EXPORT))
579 			typeset(cp, LOCAL|LOCAL_COPY|EXPORT, 0, 0, 0);
580 	}
581 
582 	if ((cp = *ap) == NULL) {
583 		rv = subst_exstat;
584 		goto Leave;
585 	} else if (!tp) {
586 		if (Flag(FRESTRICTED) && ksh_strchr_dirsep(cp)) {
587 			warningf(TRUE, "%s: restricted", cp);
588 			rv = 1;
589 			goto Leave;
590 		}
591 		tp = findcom(cp, fcflags);
592 	}
593 
594 	switch (tp->type) {
595 	  case CSHELL:			/* shell built-in */
596 		rv = call_builtin(tp, ap);
597 		break;
598 
599 	  case CFUNC:			/* function call */
600 	  {
601 		volatile int old_xflag;
602 		volatile Tflag old_inuse;
603 		const char *volatile old_kshname;
604 
605 		if (!(tp->flag & ISSET)) {
606 			struct tbl *ftp;
607 
608 			if (!tp->u.fpath) {
609 				if (tp->u2.errno_) {
610 					warningf(TRUE,
611 				"%s: can't find function definition file - %s",
612 						cp, strerror(tp->u2.errno_));
613 					rv = 126;
614 				} else {
615 					warningf(TRUE,
616 				"%s: can't find function definition file", cp);
617 					rv = 127;
618 				}
619 				break;
620 			}
621 			if (include(tp->u.fpath, 0, (char **) 0, 0) < 0) {
622 				warningf(TRUE,
623 			    "%s: can't open function definition file %s - %s",
624 					cp, tp->u.fpath, strerror(errno));
625 				rv = 127;
626 				break;
627 			}
628 			if (!(ftp = findfunc(cp, hash(cp), FALSE))
629 			    || !(ftp->flag & ISSET))
630 			{
631 				warningf(TRUE,
632 					"%s: function not defined by %s",
633 					cp, tp->u.fpath);
634 				rv = 127;
635 				break;
636 			}
637 			tp = ftp;
638 		}
639 
640 		/* ksh functions set $0 to function name, POSIX functions leave
641 		 * $0 unchanged.
642 		 */
643 		old_kshname = kshname;
644 		if (tp->flag & FKSH)
645 			kshname = ap[0];
646 		else
647 			ap[0] = (char *) kshname;
648 		e->loc->argv = ap;
649 		for (i = 0; *ap++ != NULL; i++)
650 			;
651 		e->loc->argc = i - 1;
652 		/* ksh-style functions handle getopts sanely,
653 		 * bourne/posix functions are insane...
654 		 */
655 		if (tp->flag & FKSH) {
656 			e->loc->flags |= BF_DOGETOPTS;
657 			e->loc->getopts_state = user_opt;
658 			getopts_reset(1);
659 		}
660 
661 		old_xflag = Flag(FXTRACE);
662 		Flag(FXTRACE) = tp->flag & TRACE ? TRUE : FALSE;
663 
664 		old_inuse = tp->flag & FINUSE;
665 		tp->flag |= FINUSE;
666 
667 		e->type = E_FUNC;
668 		i = ksh_sigsetjmp(e->jbuf, 0);
669 		if (i == 0) {
670 			/* seems odd to pass XERROK here, but at&t ksh does */
671 			exstat = execute(tp->val.t, flags & XERROK);
672 			i = LRETURN;
673 		}
674 		kshname = old_kshname;
675 		Flag(FXTRACE) = old_xflag;
676 		tp->flag = (tp->flag & ~FINUSE) | old_inuse;
677 		/* Were we deleted while executing?  If so, free the execution
678 		 * tree.  todo: Unfortunately, the table entry is never re-used
679 		 * until the lookup table is expanded.
680 		 */
681 		if ((tp->flag & (FDELETE|FINUSE)) == FDELETE) {
682 			if (tp->flag & ALLOC) {
683 				tp->flag &= ~ALLOC;
684 				tfree(tp->val.t, tp->areap);
685 			}
686 			tp->flag = 0;
687 		}
688 		switch (i) {
689 		  case LRETURN:
690 		  case LERROR:
691 			rv = exstat;
692 			break;
693 		  case LINTR:
694 		  case LEXIT:
695 		  case LLEAVE:
696 		  case LSHELL:
697 			quitenv();
698 			unwind(i);
699 			/*NOTREACHED*/
700 		  default:
701 			quitenv();
702 			internal_errorf(1, "CFUNC %d", i);
703 		}
704 		break;
705 	  }
706 
707 	  case CEXEC:		/* executable command */
708 	  case CTALIAS:		/* tracked alias */
709 		if (!(tp->flag&ISSET)) {
710 			/* errno_ will be set if the named command was found
711 			 * but could not be executed (permissions, no execute
712 			 * bit, directory, etc).  Print out a (hopefully)
713 			 * useful error message and set the exit status to 126.
714 			 */
715 			if (tp->u2.errno_) {
716 				warningf(TRUE, "%s: cannot execute - %s", cp,
717 					strerror(tp->u2.errno_));
718 				rv = 126;	/* POSIX */
719 			} else {
720 				warningf(TRUE, "%s: not found", cp);
721 				rv = 127;
722 			}
723 			break;
724 		}
725 
726 #ifdef KSH
727 		/* set $_ to program's full path */
728 		/* setstr() can't fail here */
729 		setstr(typeset("_", LOCAL|EXPORT, 0, INTEGER, 0),
730 		       tp->val.s, KSH_RETURN_ERROR);
731 #endif /* KSH */
732 
733 		if (flags&XEXEC) {
734 			j_exit();
735 			if (!(flags&XBGND) || Flag(FMONITOR)) {
736 				setexecsig(&sigtraps[SIGINT], SS_RESTORE_ORIG);
737 				setexecsig(&sigtraps[SIGQUIT], SS_RESTORE_ORIG);
738 			}
739 		}
740 
741 		/* to fork we set up a TEXEC node and call execute */
742 		texec.type = TEXEC;
743 		texec.left = t;	/* for tprint */
744 		texec.str = tp->val.s;
745 		texec.args = ap;
746 		rv = exchild(&texec, flags, -1);
747 		break;
748 	}
749   Leave:
750 	if (flags & XEXEC) {
751 		exstat = rv;
752 		unwind(LLEAVE);
753 	}
754 	return rv;
755 }
756 
757 static void
758 scriptexec(tp, ap)
759 	register struct op *tp;
760 	register char **ap;
761 {
762 	char *shell;
763 
764 	shell = str_val(global(EXECSHELL_STR));
765 	if (shell && *shell)
766 		shell = search(shell, path, X_OK, (int *) 0);
767 	if (!shell || !*shell)
768 		shell = EXECSHELL;
769 
770 	*tp->args-- = tp->str;
771 #ifdef	SHARPBANG
772 	{
773 		char buf[LINE];
774 		register char *cp;
775 		register int fd, n;
776 
777 		buf[0] = '\0';
778 		if ((fd = open(tp->str, O_RDONLY)) >= 0) {
779 			if ((n = read(fd, buf, LINE - 1)) > 0)
780 				buf[n] = '\0';
781 			(void) close(fd);
782 		}
783 		if ((buf[0] == '#' && buf[1] == '!' && (cp = &buf[2]))
784 # ifdef OS2
785 		    || (strncmp(buf, "extproc", 7) == 0 && isspace(buf[7])
786 			&& (cp = &buf[7]))
787 # endif /* OS2 */
788 		    )
789 		{
790 			while (*cp && (*cp == ' ' || *cp == '\t'))
791 				cp++;
792 			if (*cp && *cp != '\n') {
793 				char *a0 = cp, *a1 = (char *) 0;
794 # ifdef OS2
795 				char *a2 = cp;
796 # endif /* OS2 */
797 
798 				while (*cp && *cp != '\n' && *cp != ' '
799 				       && *cp != '\t')
800 				{
801 # ifdef OS2
802 			/* Allow shell search without prepended path
803 			 * if shell with / in pathname cannot be found.
804 			 * Use / explicitly so \ can be used if explicit
805 			 * needs to be forced.
806 			 */
807 					if (*cp == '/')
808 						a2 = cp + 1;
809 # endif /* OS2 */
810 					cp++;
811 				}
812 				if (*cp && *cp != '\n') {
813 					*cp++ = '\0';
814 					while (*cp
815 					       && (*cp == ' ' || *cp == '\t'))
816 						cp++;
817 					if (*cp && *cp != '\n') {
818 						a1 = cp;
819 						/* all one argument */
820 						while (*cp && *cp != '\n')
821 							cp++;
822 					}
823 				}
824 				if (*cp == '\n') {
825 					*cp = '\0';
826 					if (a1)
827 						*tp->args-- = a1;
828 # ifdef OS2
829 					if (a0 != a2) {
830 						char *tmp_a0 = str_nsave(a0,
831 							strlen(a0) + 5, ATEMP);
832 						if (search_access(tmp_a0, X_OK,
833 								(int *) 0))
834 							a0 = a2;
835 						afree(tmp_a0, ATEMP);
836 					}
837 # endif /* OS2 */
838 					shell = a0;
839 				}
840 			}
841 # ifdef OS2
842 		} else {
843 		        /* Use ksh documented shell default if present
844 			 * else use OS2_SHELL which is assumed to need
845 			 * the /c option and '\' as dir separator.
846 			 */
847 		         char *p = shell;
848 
849 			 shell = str_val(global("EXECSHELL"));
850 			 if (shell && *shell)
851 				 shell = search(shell, path, X_OK, (int *) 0);
852 			 if (!shell || !*shell) {
853 				 shell = p;
854 				 *tp->args-- = "/c";
855 				 for (p = tp->str; *p; p++)
856 					 if (*p == '/')
857 						 *p = '\\';
858 			 }
859 # endif /* OS2 */
860 		}
861 	}
862 #endif	/* SHARPBANG */
863 	*tp->args = shell;
864 
865 	ksh_execve(tp->args[0], tp->args, ap, 0);
866 
867 	/* report both the program that was run and the bogus shell */
868 	errorf("%s: %s: %s", tp->str, shell, strerror(errno));
869 }
870 
871 int
872 shcomexec(wp)
873 	register char **wp;
874 {
875 	register struct tbl *tp;
876 
877 	tp = tsearch(&builtins, *wp, hash(*wp));
878 	if (tp == NULL)
879 		internal_errorf(1, "shcomexec: %s", *wp);
880 	return call_builtin(tp, wp);
881 }
882 
883 /*
884  * Search function tables for a function.  If create set, a table entry
885  * is created if none is found.
886  */
887 struct tbl *
888 findfunc(name, h, create)
889 	const char *name;
890 	unsigned int h;
891 	int create;
892 {
893 	struct block *l;
894 	struct tbl *tp = (struct tbl *) 0;
895 
896 	for (l = e->loc; l; l = l->next) {
897 		tp = tsearch(&l->funs, name, h);
898 		if (tp)
899 			break;
900 		if (!l->next && create) {
901 			tp = tenter(&l->funs, name, h);
902 			tp->flag = DEFINED;
903 			tp->type = CFUNC;
904 			tp->val.t = (struct op *) 0;
905 			break;
906 		}
907 	}
908 	return tp;
909 }
910 
911 /*
912  * define function.  Returns 1 if function is being undefined (t == 0) and
913  * function did not exist, returns 0 otherwise.
914  */
915 int
916 define(name, t)
917 	const char *name;
918 	struct op *t;
919 {
920 	struct tbl *tp;
921 	int was_set = 0;
922 
923 	while (1) {
924 		tp = findfunc(name, hash(name), TRUE);
925 
926 		if (tp->flag & ISSET)
927 			was_set = 1;
928 		/* If this function is currently being executed, we zap this
929 		 * table entry so findfunc() won't see it
930 		 */
931 		if (tp->flag & FINUSE) {
932 			tp->name[0] = '\0';
933 			tp->flag &= ~DEFINED; /* ensure it won't be found */
934 			tp->flag |= FDELETE;
935 		} else
936 			break;
937 	}
938 
939 	if (tp->flag & ALLOC) {
940 		tp->flag &= ~(ISSET|ALLOC);
941 		tfree(tp->val.t, tp->areap);
942 	}
943 
944 	if (t == NULL) {		/* undefine */
945 		tdelete(tp);
946 		return was_set ? 0 : 1;
947 	}
948 
949 	tp->val.t = tcopy(t->left, tp->areap);
950 	tp->flag |= (ISSET|ALLOC);
951 	if (t->u.ksh_func)
952 		tp->flag |= FKSH;
953 
954 	return 0;
955 }
956 
957 /*
958  * add builtin
959  */
960 void
961 builtin(name, func)
962 	const char *name;
963 	int (*func) ARGS((char **));
964 {
965 	register struct tbl *tp;
966 	Tflag flag;
967 
968 	/* see if any flags should be set for this builtin */
969 	for (flag = 0; ; name++) {
970 		if (*name == '=')	/* command does variable assignment */
971 			flag |= KEEPASN;
972 		else if (*name == '*')	/* POSIX special builtin */
973 			flag |= SPEC_BI;
974 		else if (*name == '+')	/* POSIX regular builtin */
975 			flag |= REG_BI;
976 		else
977 			break;
978 	}
979 
980 	tp = tenter(&builtins, name, hash(name));
981 	tp->flag = DEFINED | flag;
982 	tp->type = CSHELL;
983 	tp->val.f = func;
984 }
985 
986 /*
987  * find command
988  * either function, hashed command, or built-in (in that order)
989  */
990 struct tbl *
991 findcom(name, flags)
992 	const char *name;
993 	int	flags;		/* FC_* */
994 {
995 	static struct tbl temp;
996 	unsigned int h = hash(name);
997 	struct tbl *tp = NULL, *tbi;
998 	int insert = Flag(FTRACKALL);	/* insert if not found */
999 	char *fpath;			/* for function autoloading */
1000 	char *npath;
1001 
1002 	if (ksh_strchr_dirsep(name) != NULL) {
1003 		insert = 0;
1004 		/* prevent FPATH search below */
1005 		flags &= ~FC_FUNC;
1006 		goto Search;
1007 	}
1008 	tbi = (flags & FC_BI) ? tsearch(&builtins, name, h) : NULL;
1009 	/* POSIX says special builtins first, then functions, then
1010 	 * POSIX regular builtins, then search path...
1011 	 */
1012 	if ((flags & FC_SPECBI) && tbi && (tbi->flag & SPEC_BI))
1013 		tp = tbi;
1014 	if (!tp && (flags & FC_FUNC)) {
1015 		tp = findfunc(name, h, FALSE);
1016 		if (tp && !(tp->flag & ISSET)) {
1017 			if ((fpath = str_val(global("FPATH"))) == null) {
1018 				tp->u.fpath = (char *) 0;
1019 				tp->u2.errno_ = 0;
1020 			} else
1021 				tp->u.fpath = search(name, fpath, R_OK,
1022 					&tp->u2.errno_);
1023 		}
1024 	}
1025 	if (!tp && (flags & FC_REGBI) && tbi && (tbi->flag & REG_BI))
1026 		tp = tbi;
1027 	/* todo: posix says non-special/non-regular builtins must
1028 	 * be triggered by some user-controllable means like a
1029 	 * special directory in PATH.  Requires modifications to
1030 	 * the search() function.  Tracked aliases should be
1031 	 * modified to allow tracking of builtin commands.
1032 	 * This should be under control of the FPOSIX flag.
1033 	 * If this is changed, also change c_whence...
1034 	 */
1035 	if (!tp && (flags & FC_UNREGBI) && tbi)
1036 		tp = tbi;
1037 	if (!tp && (flags & FC_PATH) && !(flags & FC_DEFPATH)) {
1038 		tp = tsearch(&taliases, name, h);
1039 		if (tp && (tp->flag & ISSET) && eaccess(tp->val.s, X_OK) != 0) {
1040 			if (tp->flag & ALLOC) {
1041 				tp->flag &= ~ALLOC;
1042 				afree(tp->val.s, APERM);
1043 			}
1044 			tp->flag &= ~ISSET;
1045 		}
1046 	}
1047 
1048   Search:
1049 	if ((!tp || (tp->type == CTALIAS && !(tp->flag&ISSET)))
1050 	    && (flags & FC_PATH))
1051 	{
1052 		if (!tp) {
1053 			if (insert && !(flags & FC_DEFPATH)) {
1054 				tp = tenter(&taliases, name, h);
1055 				tp->type = CTALIAS;
1056 			} else {
1057 				tp = &temp;
1058 				tp->type = CEXEC;
1059 			}
1060 			tp->flag = DEFINED;	/* make ~ISSET */
1061 		}
1062 		npath = search(name, flags & FC_DEFPATH ? def_path : path,
1063 				X_OK, &tp->u2.errno_);
1064 		if (npath) {
1065 			tp->val.s = tp == &temp ? npath : str_save(npath, APERM);
1066 			tp->flag |= ISSET|ALLOC;
1067 		} else if ((flags & FC_FUNC)
1068 			   && (fpath = str_val(global("FPATH"))) != null
1069 			   && (npath = search(name, fpath, R_OK,
1070 					      &tp->u2.errno_)) != (char *) 0)
1071 		{
1072 			/* An undocumented feature of at&t ksh is that it
1073 			 * searches FPATH if a command is not found, even
1074 			 * if the command hasn't been set up as an autoloaded
1075 			 * function (ie, no typeset -uf).
1076 			 */
1077 			tp = &temp;
1078 			tp->type = CFUNC;
1079 			tp->flag = DEFINED; /* make ~ISSET */
1080 			tp->u.fpath = npath;
1081 		}
1082 	}
1083 	return tp;
1084 }
1085 
1086 /*
1087  * flush executable commands with relative paths
1088  */
1089 void
1090 flushcom(all)
1091 	int all;		/* just relative or all */
1092 {
1093 	struct tbl *tp;
1094 	struct tstate ts;
1095 
1096 	for (twalk(&ts, &taliases); (tp = tnext(&ts)) != NULL; )
1097 		if ((tp->flag&ISSET) && (all || !ISDIRSEP(tp->val.s[0]))) {
1098 			if (tp->flag&ALLOC) {
1099 				tp->flag &= ~(ALLOC|ISSET);
1100 				afree(tp->val.s, APERM);
1101 			}
1102 			tp->flag &= ~ISSET;
1103 		}
1104 }
1105 
1106 /* Check if path is something we want to find.  Returns -1 for failure. */
1107 int
1108 search_access(path, mode, errnop)
1109 	const char *path;
1110 	int mode;
1111 	int *errnop;		/* set if candidate found, but not suitable */
1112 {
1113 #ifndef OS2
1114 	int ret, err = 0;
1115 	struct stat statb;
1116 
1117 	if (stat(path, &statb) < 0)
1118 		return -1;
1119 	ret = eaccess(path, mode);
1120 	if (ret < 0)
1121 		err = errno; /* File exists, but we can't access it */
1122 	else if (mode == X_OK
1123 		 && (!S_ISREG(statb.st_mode)
1124 		     /* This 'cause access() says root can execute everything */
1125 		     || !(statb.st_mode & (S_IXUSR|S_IXGRP|S_IXOTH))))
1126 	{
1127 		ret = -1;
1128 		err = S_ISDIR(statb.st_mode) ? EISDIR : EACCES;
1129 	}
1130 	if (err && errnop && !*errnop)
1131 		*errnop = err;
1132 	return ret;
1133 #else /* !OS2 */
1134 	/*
1135 	 * NOTE: ASSUMES path can be modified and has enough room at the
1136 	 *       end of the string for a suffix (ie, 4 extra characters).
1137 	 *	 Certain code knows this (eg, eval.c(globit()),
1138 	 *	 exec.c(search())).
1139 	 */
1140 	static char *xsuffixes[] = { ".ksh", ".exe", ".", ".sh", ".cmd",
1141 				     ".com", ".bat", (char *) 0
1142 				   };
1143 	static char *rsuffixes[] = { ".ksh", ".", ".sh", ".cmd", ".bat",
1144 				      (char *) 0
1145 				   };
1146 	int i;
1147 	char *mpath = (char *) path;
1148 	char *tp = mpath + strlen(mpath);
1149 	char *p;
1150 	char **sfx;
1151 
1152 	/* If a suffix has been specified, check if it is one of the
1153 	 * suffixes that indicate the file is executable - if so, change
1154 	 * the access test to R_OK...
1155 	 * This code assumes OS/2 files can have only one suffix...
1156 	 */
1157 	if ((p = strrchr((p = ksh_strrchr_dirsep(mpath)) ? p : mpath, '.'))) {
1158 		if (mode == X_OK)
1159 			mode = R_OK;
1160 		return search_access1(mpath, mode, errnop);
1161 	}
1162 	/* Try appending the various suffixes.  Different suffixes for
1163 	 * read and execute 'cause we don't want to read an executable...
1164 	 */
1165 	sfx = mode == R_OK ? rsuffixes : xsuffixes;
1166 	for (i = 0; sfx[i]; i++) {
1167 		strcpy(tp, p = sfx[i]);
1168 		if (search_access1(mpath, R_OK, errnop) == 0)
1169 			return 0;
1170 		*tp = '\0';
1171 	}
1172 	return -1;
1173 #endif /* !OS2 */
1174 }
1175 
1176 #ifdef OS2
1177 static int
1178 search_access1(path, mode, errnop)
1179 	const char *path;
1180 	int mode;
1181 	int *errnop;		/* set if candidate found, but not suitable */
1182 {
1183 	int ret, err = 0;
1184 	struct stat statb;
1185 
1186 	if (stat(path, &statb) < 0)
1187 		return -1;
1188 	ret = eaccess(path, mode);
1189 	if (ret < 0)
1190 		err = errno; /* File exists, but we can't access it */
1191 	else if (!S_ISREG(statb.st_mode)) {
1192 		ret = -1;
1193 		err = S_ISDIR(statb.st_mode) ? EISDIR : EACCES;
1194 	}
1195 	if (err && errnop && !*errnop)
1196 		*errnop = err;
1197 	return ret;
1198 }
1199 #endif /* OS2 */
1200 
1201 /*
1202  * search for command with PATH
1203  */
1204 char *
1205 search(name, path, mode, errnop)
1206 	const char *name;
1207 	const char *path;
1208 	int mode;		/* R_OK or X_OK */
1209 	int *errnop;		/* set if candidate found, but not suitable */
1210 {
1211 	const char *sp, *p;
1212 	char *xp;
1213 	XString xs;
1214 	int namelen;
1215 
1216 	if (errnop)
1217 		*errnop = 0;
1218 #ifdef OS2
1219 	/* Xinit() allocates 8 additional bytes, so appended suffixes won't
1220 	 * overflow the memory.
1221 	 */
1222 	namelen = strlen(name) + 1;
1223 	Xinit(xs, xp, namelen, ATEMP);
1224 	memcpy(Xstring(xs, xp), name, namelen);
1225 
1226  	if (ksh_strchr_dirsep(name)) {
1227 		if (search_access(Xstring(xs, xp), mode, errnop) >= 0)
1228 			return Xstring(xs, xp); /* not Xclose() - see above */
1229 		Xfree(xs, xp);
1230 		return NULL;
1231 	}
1232 
1233 	/* Look in current context always. (os2 style) */
1234 	if (search_access(Xstring(xs, xp), mode, errnop) == 0)
1235 		return Xstring(xs, xp); /* not Xclose() - xp may be wrong */
1236 #else /* OS2 */
1237 	if (ksh_strchr_dirsep(name)) {
1238 		if (search_access(name, mode, errnop) == 0)
1239 			return (char *) name;
1240 		return NULL;
1241 	}
1242 
1243 	namelen = strlen(name) + 1;
1244 	Xinit(xs, xp, 128, ATEMP);
1245 #endif /* OS2 */
1246 
1247 	sp = path;
1248 	while (sp != NULL) {
1249 		xp = Xstring(xs, xp);
1250 		if (!(p = strchr(sp, PATHSEP)))
1251 			p = sp + strlen(sp);
1252 		if (p != sp) {
1253 			XcheckN(xs, xp, p - sp);
1254 			memcpy(xp, sp, p - sp);
1255 			xp += p - sp;
1256 			*xp++ = DIRSEP;
1257 		}
1258 		sp = p;
1259 		XcheckN(xs, xp, namelen);
1260 		memcpy(xp, name, namelen);
1261  		if (search_access(Xstring(xs, xp), mode, errnop) == 0)
1262 #ifdef OS2
1263  			return Xstring(xs, xp); /* Not Xclose() - see above */
1264 #else /* OS2 */
1265 			return Xclose(xs, xp + namelen);
1266 #endif /* OS2 */
1267 		if (*sp++ == '\0')
1268 			sp = NULL;
1269 	}
1270 	Xfree(xs, xp);
1271 	return NULL;
1272 }
1273 
1274 static int
1275 call_builtin(tp, wp)
1276 	struct tbl *tp;
1277 	char **wp;
1278 {
1279 	int rv;
1280 
1281 	builtin_argv0 = wp[0];
1282 	builtin_flag = tp->flag;
1283 	shf_reopen(1, SHF_WR, shl_stdout);
1284 	shl_stdout_ok = 1;
1285 	ksh_getopt_reset(&builtin_opt, GF_ERROR);
1286 	rv = (*tp->val.f)(wp);
1287 	shf_flush(shl_stdout);
1288 	shl_stdout_ok = 0;
1289 	builtin_flag = 0;
1290 	builtin_argv0 = (char *) 0;
1291 	return rv;
1292 }
1293 
1294 /*
1295  * set up redirection, saving old fd's in e->savefd
1296  */
1297 static int
1298 iosetup(iop, tp)
1299 	register struct ioword *iop;
1300 	struct tbl *tp;
1301 {
1302 	register int u = -1;
1303 	char *cp = iop->name;
1304 	int iotype = iop->flag & IOTYPE;
1305 	int do_open = 1, do_close = 0, UNINITIALIZED(flags);
1306 	struct ioword iotmp;
1307 	struct stat statb;
1308 
1309 	if (iotype != IOHERE)
1310 		cp = evalonestr(cp, DOTILDE|(Flag(FTALKING_I) ? DOGLOB : 0));
1311 
1312 	/* Used for tracing and error messages to print expanded cp */
1313 	iotmp = *iop;
1314 	iotmp.name = (iotype == IOHERE) ? (char *) 0 : cp;
1315 	iotmp.flag |= IONAMEXP;
1316 
1317 	if (Flag(FXTRACE))
1318 		shellf("%s%s\n",
1319 			PS4_SUBSTITUTE(str_val(global("PS4"))),
1320 			snptreef((char *) 0, 32, "%R", &iotmp));
1321 
1322 	switch (iotype) {
1323 	  case IOREAD:
1324 		flags = O_RDONLY;
1325 		break;
1326 
1327 	  case IOCAT:
1328 		flags = O_WRONLY | O_APPEND | O_CREAT;
1329 		break;
1330 
1331 	  case IOWRITE:
1332 		flags = O_WRONLY | O_CREAT | O_TRUNC;
1333 		/* The stat() is here to allow redirections to
1334 		 * things like /dev/null without error.
1335 		 */
1336 		if (Flag(FNOCLOBBER) && !(iop->flag & IOCLOB)
1337 		    && (stat(cp, &statb) < 0 || S_ISREG(statb.st_mode)))
1338 			flags |= O_EXCL;
1339 		break;
1340 
1341 	  case IORDWR:
1342 		flags = O_RDWR | O_CREAT;
1343 		break;
1344 
1345 	  case IOHERE:
1346 		do_open = 0;
1347 		/* herein() returns -2 if error has been printed */
1348 		u = herein(iop->heredoc, iop->flag & IOEVAL);
1349 		/* cp may have wrong name */
1350 		break;
1351 
1352 	  case IODUP:
1353 	  {
1354 		const char *emsg;
1355 
1356 		do_open = 0;
1357 		if (*cp == '-' && !cp[1]) {
1358 			u = 1009;	 /* prevent error return below */
1359 			do_close = 1;
1360 		} else if ((u = check_fd(cp,
1361 				X_OK | ((iop->flag & IORDUP) ? R_OK : W_OK),
1362 				&emsg)) < 0)
1363 		{
1364 			warningf(TRUE, "%s: %s",
1365 				snptreef((char *) 0, 32, "%R", &iotmp), emsg);
1366 			return -1;
1367 		}
1368 		if (u == iop->unit)
1369 			return 0;		/* "dup from" == "dup to" */
1370 		break;
1371 	  }
1372 	}
1373 	if (do_open) {
1374 		if (Flag(FRESTRICTED) && (flags & O_CREAT)) {
1375 			warningf(TRUE, "%s: restricted", cp);
1376 			return -1;
1377 		}
1378 		u = open(cp, flags, 0666);
1379 #ifdef OS2
1380 		if (u < 0 && strcmp(cp, "/dev/null") == 0)
1381 			u = open("nul", flags, 0666);
1382 #endif /* OS2 */
1383 	}
1384 	if (u < 0) {
1385 		/* herein() may already have printed message */
1386 		if (u == -1)
1387 			warningf(TRUE, "cannot %s %s: %s",
1388 			       iotype == IODUP ? "dup"
1389 				: (iotype == IOREAD || iotype == IOHERE) ?
1390 				    "open" : "create", cp, strerror(errno));
1391 		return -1;
1392 	}
1393 	/* Do not save if it has already been redirected (i.e. "cat >x >y"). */
1394 	if (e->savefd[iop->unit] == 0) {
1395 		/* If these are the same, it means unit was previously closed */
1396 		if (u == iop->unit)
1397 			e->savefd[iop->unit] = -1;
1398 		else
1399 			/* c_exec() assumes e->savefd[fd] set for any
1400 			 * redirections.  Ask savefd() not to close iop->unit;
1401 			 * this allows error messages to be seen if iop->unit
1402 			 * is 2; also means we can't lose the fd (eg, both
1403 			 * dup2 below and dup2 in restfd() failing).
1404 			 */
1405 			e->savefd[iop->unit] = savefd(iop->unit, 1);
1406 	}
1407 
1408 	if (do_close)
1409 		close(iop->unit);
1410 	else if (u != iop->unit) {
1411 		if (ksh_dup2(u, iop->unit, TRUE) < 0) {
1412 			warningf(TRUE,
1413 				"could not finish (dup) redirection %s: %s",
1414 				snptreef((char *) 0, 32, "%R", &iotmp),
1415 				strerror(errno));
1416 			if (iotype != IODUP)
1417 				close(u);
1418 			return -1;
1419 		}
1420 		if (iotype != IODUP)
1421 			close(u);
1422 #ifdef KSH
1423 		/* Touching any co-process fd in an empty exec
1424 		 * causes the shell to close its copies
1425 		 */
1426 		else if (tp && tp->type == CSHELL && tp->val.f == c_exec) {
1427 			if (iop->flag & IORDUP)	/* possible exec <&p */
1428 				coproc_read_close(u);
1429 			else			/* possible exec >&p */
1430 				coproc_write_close(u);
1431 		}
1432 #endif /* KSH */
1433 	}
1434 	if (u == 2) /* Clear any write errors */
1435 		shf_reopen(2, SHF_WR, shl_out);
1436 	return 0;
1437 }
1438 
1439 /*
1440  * open here document temp file.
1441  * if unquoted here, expand here temp file into second temp file.
1442  */
1443 static int
1444 herein(content, sub)
1445 	const char *content;
1446 	int sub;
1447 {
1448 	volatile int fd = -1;
1449 	struct source *s, *volatile osource;
1450 	struct shf *volatile shf;
1451 	struct temp *h;
1452 	int i;
1453 
1454 	/* ksh -c 'cat << EOF' can cause this... */
1455 	if (content == (char *) 0) {
1456 		warningf(TRUE, "here document missing");
1457 		return -2; /* special to iosetup(): don't print error */
1458 	}
1459 
1460 	/* Create temp file to hold content (done before newenv so temp
1461 	 * doesn't get removed too soon).
1462 	 */
1463 	h = maketemp(ATEMP, TT_HEREDOC_EXP, &e->temps);
1464 	if (!(shf = h->shf) || (fd = open(h->name, O_RDONLY, 0)) < 0) {
1465 		warningf(TRUE, "can't %s temporary file %s: %s",
1466 			!shf ? "create" : "open",
1467 			h->name, strerror(errno));
1468 		if (shf)
1469 			shf_close(shf);
1470 		return -2 /* special to iosetup(): don't print error */;
1471 	}
1472 
1473 	osource = source;
1474 	newenv(E_ERRH);
1475 	i = ksh_sigsetjmp(e->jbuf, 0);
1476 	if (i) {
1477 		source = osource;
1478 		quitenv();
1479 		shf_close(shf);	/* after quitenv */
1480 		close(fd);
1481 		return -2; /* special to iosetup(): don't print error */
1482 	}
1483 	if (sub) {
1484 		/* Do substitutions on the content of heredoc */
1485 		s = pushs(SSTRING, ATEMP);
1486 		s->start = s->str = content;
1487 		source = s;
1488 		if (yylex(ONEWORD) != LWORD)
1489 			internal_errorf(1, "herein: yylex");
1490 		source = osource;
1491 		shf_puts(evalstr(yylval.cp, 0), shf);
1492 	} else
1493 		shf_puts(content, shf);
1494 
1495 	quitenv();
1496 
1497 	if (shf_close(shf) == EOF) {
1498 		close(fd);
1499 		warningf(TRUE, "error writing %s: %s", h->name,
1500 			strerror(errno));
1501 		return -2; /* special to iosetup(): don't print error */
1502 	}
1503 
1504 	return fd;
1505 }
1506 
1507 #ifdef KSH
1508 /*
1509  *	ksh special - the select command processing section
1510  *	print the args in column form - assuming that we can
1511  */
1512 static char *
1513 do_selectargs(ap, print_menu)
1514 	register char **ap;
1515 	bool_t print_menu;
1516 {
1517 	static const char *const read_args[] = {
1518 					"read", "-r", "REPLY", (char *) 0
1519 				    };
1520 	char *s;
1521 	int i, argct;
1522 
1523 	for (argct = 0; ap[argct]; argct++)
1524 		;
1525 	while (1) {
1526 		/* Menu is printed if
1527 		 *	- this is the first time around the select loop
1528 		 *	- the user enters a blank line
1529 		 *	- the REPLY parameter is empty
1530 		 */
1531 		if (print_menu || !*str_val(global("REPLY")))
1532 			pr_menu(ap);
1533 		shellf("%s", str_val(global("PS3")));
1534 		if (call_builtin(findcom("read", FC_BI), (char **) read_args))
1535 			return (char *) 0;
1536 		s = str_val(global("REPLY"));
1537 		if (*s) {
1538 			i = atoi(s);
1539 			return (i >= 1 && i <= argct) ? ap[i - 1] : null;
1540 		}
1541 		print_menu = 1;
1542 	}
1543 }
1544 
1545 struct select_menu_info {
1546 	char	*const *args;
1547 	int	arg_width;
1548 	int	num_width;
1549 } info;
1550 
1551 static char *select_fmt_entry ARGS((void *arg, int i, char *buf, int buflen));
1552 
1553 /* format a single select menu item */
1554 static char *
1555 select_fmt_entry(arg, i, buf, buflen)
1556 	void *arg;
1557 	int i;
1558 	char *buf;
1559 	int buflen;
1560 {
1561 	struct select_menu_info *smi = (struct select_menu_info *) arg;
1562 
1563 	shf_snprintf(buf, buflen, "%*d) %s",
1564 		smi->num_width, i + 1, smi->args[i]);
1565 	return buf;
1566 }
1567 
1568 /*
1569  *	print a select style menu
1570  */
1571 int
1572 pr_menu(ap)
1573 	char *const *ap;
1574 {
1575 	struct select_menu_info smi;
1576 	char *const *pp;
1577 	int nwidth, dwidth;
1578 	int i, n;
1579 
1580 	/* Width/column calculations were done once and saved, but this
1581 	 * means select can't be used recursively so we re-calculate each
1582 	 * time (could save in a structure that is returned, but its probably
1583 	 * not worth the bother).
1584 	 */
1585 
1586 	/*
1587 	 * get dimensions of the list
1588 	 */
1589 	for (n = 0, nwidth = 0, pp = ap; *pp; n++, pp++) {
1590 		i = strlen(*pp);
1591 		nwidth = (i > nwidth) ? i : nwidth;
1592 	}
1593 	/*
1594 	 * we will print an index of the form
1595 	 *	%d)
1596 	 * in front of each entry
1597 	 * get the max width of this
1598 	 */
1599 	for (i = n, dwidth = 1; i >= 10; i /= 10)
1600 		dwidth++;
1601 
1602 	smi.args = ap;
1603 	smi.arg_width = nwidth;
1604 	smi.num_width = dwidth;
1605 	print_columns(shl_out, n, select_fmt_entry, (void *) &smi,
1606 		dwidth + nwidth + 2, 1);
1607 
1608 	return n;
1609 }
1610 
1611 /* XXX: horrible kludge to fit within the framework */
1612 
1613 static char *plain_fmt_entry ARGS((void *arg, int i, char *buf, int buflen));
1614 
1615 static char *
1616 plain_fmt_entry(arg, i, buf, buflen)
1617 	void *arg;
1618 	int i;
1619 	char *buf;
1620 	int buflen;
1621 {
1622 	shf_snprintf(buf, buflen, "%s", ((char *const *)arg)[i]);
1623 	return buf;
1624 }
1625 
1626 int
1627 pr_list(ap)
1628 	char *const *ap;
1629 {
1630 	char *const *pp;
1631 	int nwidth;
1632 	int i, n;
1633 
1634 	for (n = 0, nwidth = 0, pp = ap; *pp; n++, pp++) {
1635 		i = strlen(*pp);
1636 		nwidth = (i > nwidth) ? i : nwidth;
1637 	}
1638 	print_columns(shl_out, n, plain_fmt_entry, (void *) ap, nwidth + 1, 0);
1639 
1640 	return n;
1641 }
1642 #endif /* KSH */
1643 #ifdef KSH
1644 
1645 /*
1646  *	[[ ... ]] evaluation routines
1647  */
1648 
1649 extern const char *const dbtest_tokens[];
1650 extern const char db_close[];
1651 
1652 /* Test if the current token is a whatever.  Accepts the current token if
1653  * it is.  Returns 0 if it is not, non-zero if it is (in the case of
1654  * TM_UNOP and TM_BINOP, the returned value is a Test_op).
1655  */
1656 static int
1657 dbteste_isa(te, meta)
1658 	Test_env *te;
1659 	Test_meta meta;
1660 {
1661 	int ret = 0;
1662 	int uqword;
1663 	char *p;
1664 
1665 	if (!*te->pos.wp)
1666 		return meta == TM_END;
1667 
1668 	/* unquoted word? */
1669 	for (p = *te->pos.wp; *p == CHAR; p += 2)
1670 		;
1671 	uqword = *p == EOS;
1672 
1673 	if (meta == TM_UNOP || meta == TM_BINOP) {
1674 		if (uqword) {
1675 			char buf[8];	/* longer than the longest operator */
1676 			char *q = buf;
1677 			for (p = *te->pos.wp; *p == CHAR
1678 					      && q < &buf[sizeof(buf) - 1];
1679 					      p += 2)
1680 				*q++ = p[1];
1681 			*q = '\0';
1682 			ret = (int) test_isop(te, meta, buf);
1683 		}
1684 	} else if (meta == TM_END)
1685 		ret = 0;
1686 	else
1687 		ret = uqword
1688 			&& strcmp(*te->pos.wp, dbtest_tokens[(int) meta]) == 0;
1689 
1690 	/* Accept the token? */
1691 	if (ret)
1692 		te->pos.wp++;
1693 
1694 	return ret;
1695 }
1696 
1697 static const char *
1698 dbteste_getopnd(te, op, do_eval)
1699 	Test_env *te;
1700 	Test_op op;
1701 	int do_eval;
1702 {
1703 	char *s = *te->pos.wp;
1704 
1705 	if (!s)
1706 		return (char *) 0;
1707 
1708 	te->pos.wp++;
1709 
1710 	if (!do_eval)
1711 		return null;
1712 
1713 	if (op == TO_STEQL || op == TO_STNEQ)
1714 		s = evalstr(s, DOTILDE | DOPAT);
1715 	else
1716 		s = evalstr(s, DOTILDE);
1717 
1718 	return s;
1719 }
1720 
1721 static int
1722 dbteste_eval(te, op, opnd1, opnd2, do_eval)
1723 	Test_env *te;
1724 	Test_op op;
1725 	const char *opnd1;
1726 	const char *opnd2;
1727 	int do_eval;
1728 {
1729 	return test_eval(te, op, opnd1, opnd2, do_eval);
1730 }
1731 
1732 static void
1733 dbteste_error(te, offset, msg)
1734 	Test_env *te;
1735 	int offset;
1736 	const char *msg;
1737 {
1738 	te->flags |= TEF_ERROR;
1739 	internal_errorf(0, "dbteste_error: %s (offset %d)", msg, offset);
1740 }
1741 #endif /* KSH */
1742