xref: /netbsd-src/bin/ksh/exec.c (revision 2a399c6883d870daece976daec6ffa7bb7f934ce)
1 /*	$NetBSD: exec.c,v 1.3 1997/07/20 17:42:03 christos Exp $	*/
2 
3 /*
4  * execute command tree
5  */
6 
7 #include "sh.h"
8 #include "c_test.h"
9 #include <ctype.h>
10 #include "ksh_stat.h"
11 
12 /* Does ps4 get parameter substitutions done? */
13 #ifdef KSH
14 # define PS4_SUBSTITUTE(s)	substitute((s), 0)
15 #else
16 # define PS4_SUBSTITUTE(s)	(s)
17 #endif /* KSH */
18 
19 static int	comexec	 ARGS((struct op *t, struct tbl *volatile tp, char **ap,
20 			      int volatile flags));
21 static void	scriptexec ARGS((struct op *tp, char **ap));
22 static int	call_builtin ARGS((struct tbl *tp, char **wp));
23 static int	iosetup ARGS((struct ioword *iop, struct tbl *tp));
24 static int	herein ARGS((char *hname, int sub));
25 #ifdef KSH
26 static char 	*do_selectargs ARGS((char **ap, bool_t print_menu));
27 #endif /* KSH */
28 #ifdef KSH
29 static int	dbteste_isa ARGS((Test_env *te, Test_meta meta));
30 static const char *dbteste_getopnd ARGS((Test_env *te, Test_op op,
31 					 int do_eval));
32 static int	dbteste_eval ARGS((Test_env *te, Test_op op, const char *opnd1,
33 				const char *opnd2, int do_eval));
34 static void	dbteste_error ARGS((Test_env *te, int offset, const char *msg));
35 #endif /* KSH */
36 #ifdef OS2
37 static int	search_access1 ARGS((const char *path, int mode, int *errnop));
38 #endif /* OS2 */
39 
40 
41 /*
42  * handle systems that don't have F_SETFD
43  */
44 #ifndef F_SETFD
45 # ifndef MAXFD
46 #   define  MAXFD 64
47 # endif
48 /* a bit field would be smaller, but this will work */
49 static char clexec_tab[MAXFD+1];
50 #endif
51 
52 /*
53  * we now use this function always.
54  */
55 int
56 fd_clexec(fd)
57     int fd;
58 {
59 #ifndef F_SETFD
60 	if (fd >= 0 && fd < sizeof(clexec_tab)) {
61 		clexec_tab[fd] = 1;
62 		return 0;
63 	}
64 	return -1;
65 #else
66 	return fcntl(fd, F_SETFD, 1);
67 #endif
68 }
69 
70 
71 /*
72  * execute command tree
73  */
74 int
75 execute(t, flags)
76 	struct op * volatile t;
77 	volatile int flags;	/* if XEXEC don't fork */
78 {
79 	int i;
80 	volatile int rv = 0;
81 	int pv[2];
82 	char ** volatile ap;
83 	char *s, *cp;
84 	struct ioword **iowp;
85 	struct tbl *tp = NULL;
86 
87 	if (t == NULL)
88 		return 0;
89 
90 	/* Is this the end of a pipeline?  If so, we want to evaluate the
91 	 * command arguments
92 	bool_t eval_done = FALSE;
93 	if ((flags&XFORK) && !(flags&XEXEC) && (flags&XPCLOSE)) {
94 		eval_done = TRUE;
95 		tp = eval_execute_args(t, &ap);
96 	}
97 	 */
98 	if ((flags&XFORK) && !(flags&XEXEC) && t->type != TPIPE)
99 		return exchild(t, flags, -1); /* run in sub-process */
100 
101 	newenv(E_EXEC);
102 	if (trap)
103 		runtraps(0);
104 
105 	if (t->type == TCOM) {
106 		/* Clear subst_exstat before argument expansion.  Used by
107 		 * null commands (see comexec()) and by c_set().
108 		 */
109 		subst_exstat = 0;
110 
111 		/* POSIX says expand command words first, then redirections,
112 		 * and assignments last..
113 		 */
114 		ap = eval(t->args, t->u.evalflags | DOBLANK | DOGLOB | DOTILDE);
115 		if (Flag(FXTRACE) && ap[0]) {
116 			shf_fprintf(shl_out, "%s",
117 				PS4_SUBSTITUTE(str_val(global("PS4"))));
118 			for (i = 0; ap[i]; i++)
119 				shf_fprintf(shl_out, "%s%s", ap[i],
120 					ap[i + 1] ? space : newline);
121 			shf_flush(shl_out);
122 		}
123 		if (ap[0])
124 			tp = findcom(ap[0], FC_BI|FC_FUNC);
125 	}
126 
127 	if (t->ioact != NULL || t->type == TPIPE || t->type == TCOPROC) {
128 		e->savefd = (short *) alloc(sizeofN(short, NUFILE), ATEMP);
129 		/* initialize to not redirected */
130 		memset(e->savefd, 0, sizeofN(short, NUFILE));
131 	}
132 
133 	/* do redirection, to be restored in quitenv() */
134 	if (t->ioact != NULL)
135 		for (iowp = t->ioact; *iowp != NULL; iowp++) {
136 			if (iosetup(*iowp, tp) < 0) {
137 				exstat = rv = 1;
138 				/* Redirection failures for special commands
139 				 * cause (non-interactive) shell to exit.
140 				 */
141 				if (tp && tp->type == CSHELL
142 				    && (tp->flag & SPEC_BI))
143 					errorf(null);
144 				/* Deal with FERREXIT, quitenv(), etc. */
145 				goto Break;
146 			}
147 		}
148 
149 	switch(t->type) {
150 	  case TCOM:
151 		rv = comexec(t, tp, ap, flags);
152 		break;
153 
154 	  case TPAREN:
155 		rv = execute(t->left, flags|XFORK);
156 		break;
157 
158 	  case TPIPE:
159 		flags |= XFORK;
160 		flags &= ~XEXEC;
161 		e->savefd[0] = savefd(0, 0);
162 		(void) ksh_dup2(e->savefd[0], 0, FALSE); /* stdin of first */
163 		e->savefd[1] = savefd(1, 0);
164 		while (t->type == TPIPE) {
165 			openpipe(pv);
166 			(void) ksh_dup2(pv[1], 1, FALSE); /* stdout of curr */
167 			/* Let exchild() close pv[0] in child
168 			 * (if this isn't done, commands like
169 			 *    (: ; cat /etc/termcap) | sleep 1
170 			 *  will hang forever).
171 			 */
172 			exchild(t->left, flags|XPIPEO|XCCLOSE, pv[0]);
173 			(void) ksh_dup2(pv[0], 0, FALSE); /* stdin of next */
174 			closepipe(pv);
175 			flags |= XPIPEI;
176 			t = t->right;
177 		}
178 		restfd(1, e->savefd[1]); /* stdout of last */
179 		e->savefd[1] = 0; /* no need to re-restore this */
180 		/* Let exchild() close 0 in parent, after fork, before wait */
181 		i = exchild(t, flags|XPCLOSE, 0);
182 		if (!(flags&XBGND) && !(flags&XXCOM))
183 			rv = i;
184 		break;
185 
186 	  case TLIST:
187 		while (t->type == TLIST) {
188 			execute(t->left, flags & XERROK);
189 			t = t->right;
190 		}
191 		rv = execute(t, flags & XERROK);
192 		break;
193 
194 #ifdef KSH
195 	  case TCOPROC:
196 	  {
197 # ifdef JOB_SIGS
198 		sigset_t	omask;
199 # endif /* JOB_SIGS */
200 
201 # ifdef JOB_SIGS
202 		/* Block sigchild as we are using things changed in the
203 		 * signal handler
204 		 */
205 		sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
206 		e->type = E_ERRH;
207 		i = ksh_sigsetjmp(e->jbuf, 0);
208 		if (i) {
209 			sigprocmask(SIG_SETMASK, &omask, (sigset_t *) 0);
210 			quitenv();
211 			unwind(i);
212 			/*NOTREACHED*/
213 		}
214 # endif /* JOB_SIGS */
215 		/* Already have a (live) co-process? */
216 		if (coproc.job && coproc.write >= 0)
217 			errorf("coprocess already exists");
218 
219 		/* Can we re-use the existing co-process pipe? */
220 		coproc_cleanup(TRUE);
221 
222 		/* do this before opening pipes, in case these fail */
223 		e->savefd[0] = savefd(0, 0);
224 		e->savefd[1] = savefd(1, 0);
225 
226 		openpipe(pv);
227 		ksh_dup2(pv[0], 0, FALSE);
228 		close(pv[0]);
229 		coproc.write = pv[1];
230 		coproc.job = (void *) 0;
231 
232 		if (coproc.readw >= 0)
233 			ksh_dup2(coproc.readw, 1, FALSE);
234 		else {
235 			openpipe(pv);
236 			coproc.read = pv[0];
237 			ksh_dup2(pv[1], 1, FALSE);
238 			coproc.readw = pv[1];	 /* closed before first read */
239 			coproc.njobs = 0;
240 			/* create new coprocess id */
241 			++coproc.id;
242 		}
243 # ifdef JOB_SIGS
244 		sigprocmask(SIG_SETMASK, &omask, (sigset_t *) 0);
245 		e->type = E_EXEC; /* no more need for error handler */
246 # endif /* JOB_SIGS */
247 
248 		/* exchild() closes coproc.* in child after fork,
249 		 * will also increment coproc.njobs when the
250 		 * job is actually created.
251 		 */
252 		flags &= ~XEXEC;
253 		exchild(t->left, flags|XBGND|XFORK|XCOPROC|XCCLOSE,
254 			coproc.readw);
255 		break;
256 	  }
257 #endif /* KSH */
258 
259 	  case TASYNC:
260 		/* XXX non-optimal, I think - "(foo &)", forks for (),
261 		 * forks again for async...  parent should optimize
262 		 * this to "foo &"...
263 		 */
264 		rv = execute(t->left, (flags&~XEXEC)|XBGND|XFORK);
265 		break;
266 
267 	  case TOR:
268 	  case TAND:
269 		rv = execute(t->left, XERROK);
270 		if (t->right != NULL && (rv == 0) == (t->type == TAND))
271 			rv = execute(t->right, flags & XERROK);
272 		else
273 			flags |= XERROK;
274 		break;
275 
276 	  case TBANG:
277 		rv = !execute(t->right, XERROK);
278 		break;
279 
280 #ifdef KSH
281 	  case TDBRACKET:
282 	    {
283 		Test_env te;
284 
285 		te.flags = TEF_DBRACKET;
286 		te.pos.wp = t->args;
287 		te.isa = dbteste_isa;
288 		te.getopnd = dbteste_getopnd;
289 		te.eval = dbteste_eval;
290 		te.error = dbteste_error;
291 
292 		rv = test_parse(&te);
293 		break;
294 	    }
295 #endif /* KSH */
296 
297 	  case TFOR:
298 #ifdef KSH
299 	  case TSELECT:
300 	    {
301 		volatile bool_t is_first = TRUE;
302 #endif /* KSH */
303 		ap = (t->vars != NULL) ?
304 			  eval(t->vars, DOBLANK|DOGLOB|DOTILDE)
305 			: e->loc->argv + 1;
306 		e->type = E_LOOP;
307 		while (1) {
308 			i = ksh_sigsetjmp(e->jbuf, 0);
309 			if (!i)
310 				break;
311 			if ((e->flags&EF_BRKCONT_PASS)
312 			    || (i != LBREAK && i != LCONTIN))
313 			{
314 				quitenv();
315 				unwind(i);
316 			} else if (i == LBREAK) {
317 				rv = 0;
318 				goto Break;
319 			}
320 		}
321 		rv = 0; /* in case of a continue */
322 		if (t->type == TFOR) {
323 			struct tbl *vq;
324 
325 			while (*ap != NULL) {
326 				vq = global(t->str);
327 				if (vq->flag & RDONLY)
328 					errorf("%s is read only", t->str);
329 				setstr(vq, *ap++);
330 				rv = execute(t->left, flags & XERROK);
331 			}
332 		}
333 #ifdef KSH
334 		else { /* TSELECT */
335 			struct tbl *vq;
336 
337 			for (;;) {
338 				if (!(cp = do_selectargs(ap, is_first))) {
339 					rv = 1;
340 					break;
341 				}
342 				is_first = FALSE;
343 				vq = global(t->str);
344 				if (vq->flag & RDONLY)
345 					errorf("%s is read only", t->str);
346 				setstr(vq, cp);
347 				rv = execute(t->left, flags & XERROK);
348 			}
349 		}
350 	    }
351 #endif /* KSH */
352 		break;
353 
354 	  case TWHILE:
355 	  case TUNTIL:
356 		e->type = E_LOOP;
357 		while (1) {
358 			i = ksh_sigsetjmp(e->jbuf, 0);
359 			if (!i)
360 				break;
361 			if ((e->flags&EF_BRKCONT_PASS)
362 			    || (i != LBREAK && i != LCONTIN))
363 			{
364 				quitenv();
365 				unwind(i);
366 			} else if (i == LBREAK) {
367 				rv = 0;
368 				goto Break;
369 			}
370 		}
371 		rv = 0; /* in case of a continue */
372 		while ((execute(t->left, XERROK) == 0) == (t->type == TWHILE))
373 			rv = execute(t->right, flags & XERROK);
374 		break;
375 
376 	  case TIF:
377 	  case TELIF:
378 		if (t->right == NULL)
379 			break;	/* should be error */
380 		rv = execute(t->left, XERROK) == 0 ?
381 			execute(t->right->left, flags & XERROK) :
382 			execute(t->right->right, flags & XERROK);
383 		break;
384 
385 	  case TCASE:
386 		cp = evalstr(t->str, DOTILDE);
387 		for (t = t->left; t != NULL && t->type == TPAT; t = t->right)
388 		    for (ap = t->vars; *ap; ap++)
389 			if ((s = evalstr(*ap, DOTILDE|DOPAT))
390 			    && gmatch(cp, s, FALSE))
391 				goto Found;
392 		break;
393 	  Found:
394 		rv = execute(t->left, flags & XERROK);
395 		break;
396 
397 	  case TBRACE:
398 		rv = execute(t->left, flags & XERROK);
399 		break;
400 
401 	  case TFUNCT:
402 		rv = define(t->str, t);
403 		break;
404 
405 	  case TTIME:
406 		rv = timex(t, flags);
407 		break;
408 
409 	  case TEXEC:		/* an eval'd TCOM */
410 		s = t->args[0];
411 		ap = makenv();
412 #ifndef F_SETFD
413 		for (i = 0; i < sizeof(clexec_tab); i++)
414 			if (clexec_tab[i]) {
415 				close(i);
416 				clexec_tab[i] = 0;
417 			}
418 #endif
419 		restoresigs();
420 		cleanup_proc_env();
421 		ksh_execve(t->str, t->args, ap);
422 		if (errno == ENOEXEC)
423 			scriptexec(t, ap);
424 		else
425 			errorf("%s: %s", s, strerror(errno));
426 	}
427     Break:
428 	exstat = rv;
429 
430 	quitenv();		/* restores IO */
431 	if ((flags&XEXEC))
432 		exit(rv);	/* exit child */
433 	if (rv != 0 && !(flags & XERROK)) {
434 		if (Flag(FERREXIT))
435 			unwind(LERROR);
436 		trapsig(SIGERR_);
437 	}
438 	return rv;
439 }
440 
441 /*
442  * execute simple command
443  */
444 
445 static int
446 comexec(t, tp, ap, flags)
447 	struct op *t;
448 	struct tbl *volatile tp;
449 	register char **ap;
450 	int volatile flags;
451 {
452 	int i;
453 	int rv = 0;
454 	register char *cp;
455 	register char **lastp;
456 	static struct op texec; /* Must be static (XXX but why?) */
457 	int type_flags;
458 	int keepasn_ok;
459 	int fcflags = FC_BI|FC_FUNC|FC_PATH;
460 #ifdef __GNUC__
461 	(void) &rv;
462 #endif
463 
464 	/* snag the last argument for $_ XXX not the same as at&t ksh,
465 	 * which only seems to set $_ after a newline (but not in
466 	 * functions/dot scripts, but in interactive and scipt) -
467 	 * perhaps save last arg here and set it in shell()?.
468 	 */
469 	if (*(lastp = ap)) {
470 		while (*++lastp)
471 			;
472 		setstr(typeset("_", LOCAL, 0, 0, 0), *--lastp);
473 	}
474 
475 	/* Deal with the shell builtins builtin, exec and command since
476 	 * they can be followed by other commands.  This must be done before
477 	 * we know if we should create a local block, which must be done
478 	 * before we can do a path search (in case the assignments change
479 	 * PATH).
480 	 * Odd cases:
481 	 *   FOO=bar exec > /dev/null		FOO is kept but not exported
482 	 *   FOO=bar exec foobar		FOO is exported
483 	 *   FOO=bar command exec > /dev/null	FOO is neither kept nor exported
484 	 *   FOO=bar command			FOO is neither kept nor exported
485 	 *   PATH=... foobar			use new PATH in foobar search
486 	 */
487 	keepasn_ok = 1;
488 	while (tp && tp->type == CSHELL) {
489 		fcflags = FC_BI|FC_FUNC|FC_PATH;/* undo effects of command */
490 		if (tp->val.f == c_builtin) {
491 			if ((cp = *++ap) == NULL) {
492 				tp = NULL;
493 				break;
494 			}
495 			tp = findcom(cp, FC_BI);
496 			if (tp == NULL)
497 				errorf("builtin: %s: not a builtin", cp);
498 			continue;
499 		} else if (tp->val.f == c_exec) {
500 			if (ap[1] == NULL)
501 				break;
502 			ap++;
503 			flags |= XEXEC;
504 		} else if (tp->val.f == c_command) {
505 			int optc, saw_p = 0;
506 
507 			/* Ugly dealing with options in two places (here and
508 			 * in c_command(), but such is life)
509 			 */
510 			ksh_getopt_reset(&builtin_opt, 0);
511 			while ((optc = ksh_getopt(ap, &builtin_opt, ":p"))
512 									== 'p')
513 				saw_p = 1;
514 			if (optc != EOF)
515 				break;	/* command -vV or something */
516 			/* don't look for functions */
517 			fcflags = FC_BI|FC_PATH;
518 			if (saw_p) {
519 				if (Flag(FRESTRICTED)) {
520 					warningf(TRUE,
521 						"command -p: restricted");
522 					rv = 1;
523 					goto Leave;
524 				}
525 				fcflags |= FC_DEFPATH;
526 			}
527 			ap += builtin_opt.optind;
528 			/* POSIX says special builtins lose their status
529 			 * if accessed using command.
530 			 */
531 			keepasn_ok = 0;
532 			if (!ap[0]) {
533 				/* ensure command with no args exits with 0 */
534 				subst_exstat = 0;
535 				break;
536 			}
537 		} else
538 			break;
539 		tp = findcom(ap[0], fcflags & (FC_BI|FC_FUNC));
540 	}
541 	if (keepasn_ok && (!ap[0] || (tp && (tp->flag & KEEPASN))))
542 		type_flags = 0;
543 	else {
544 		/* create new variable/function block */
545 		newblock();
546 		/* ksh functions don't keep assignments, POSIX functions do. */
547 		if (keepasn_ok && tp && tp->type == CFUNC
548 		    && !(tp->flag & FKSH))
549 			type_flags = 0;
550 		else
551 			type_flags = LOCAL|LOCAL_COPY|EXPORT;
552 	}
553 	if (Flag(FEXPORT))
554 		type_flags |= EXPORT;
555 	for (i = 0; t->vars[i]; i++) {
556 		cp = evalstr(t->vars[i], DOASNTILDE);
557 		if (Flag(FXTRACE)) {
558 			if (i == 0)
559 				shf_fprintf(shl_out, "%s",
560 					PS4_SUBSTITUTE(str_val(global("PS4"))));
561 			shf_fprintf(shl_out, "%s%s", cp,
562 				t->vars[i + 1] ? space : newline);
563 			if (!t->vars[i + 1])
564 				shf_flush(shl_out);
565 		}
566 		typeset(cp, type_flags, 0, 0, 0);
567 	}
568 
569 	if ((cp = *ap) == NULL) {
570 		rv = subst_exstat;
571 		goto Leave;
572 	} else if (!tp) {
573 		if (Flag(FRESTRICTED) && ksh_strchr_dirsep(cp)) {
574 			warningf(TRUE, "%s: restricted", cp);
575 			rv = 1;
576 			goto Leave;
577 		}
578 		tp = findcom(cp, fcflags);
579 	}
580 
581 	switch (tp->type) {
582 	  case CSHELL:			/* shell built-in */
583 		rv = call_builtin(tp, ap);
584 		break;
585 
586 	  case CFUNC:			/* function call */
587 	  {
588 		volatile int old_xflag;
589 		volatile Tflag old_inuse;
590 		const char *volatile old_kshname;
591 
592 		if (!(tp->flag & ISSET)) {
593 			struct tbl *ftp;
594 
595 			if (!tp->u.fpath) {
596 				if (tp->u2.errno_) {
597 					warningf(TRUE,
598 				"%s: can't find function definition file - %s",
599 						cp, strerror(tp->u2.errno_));
600 					rv = 126;
601 				} else {
602 					warningf(TRUE,
603 				"%s: can't find function definition file", cp);
604 					rv = 127;
605 				}
606 				break;
607 			}
608 			if (include(tp->u.fpath, 0, (char **) 0, 0) < 0) {
609 				warningf(TRUE,
610 			    "%s: can't open function definition file %s - %s",
611 					cp, tp->u.fpath, strerror(errno));
612 				rv = 127;
613 				break;
614 			}
615 			if (!(ftp = findfunc(cp, hash(cp), FALSE))
616 			    || !(ftp->flag & ISSET))
617 			{
618 				warningf(TRUE,
619 					"%s: function not defined by %s",
620 					cp, tp->u.fpath);
621 				rv = 127;
622 				break;
623 			}
624 			tp = ftp;
625 		}
626 
627 		/* ksh functions set $0 to function name, POSIX functions leave
628 		 * $0 unchanged.
629 		 */
630 		old_kshname = kshname;
631 		if (tp->flag & FKSH)
632 			kshname = ap[0];
633 		e->loc->argv = ap;
634 		for (i = 0; *ap++ != NULL; i++)
635 			;
636 		e->loc->argc = i - 1;
637 		getopts_reset(1);
638 
639 		old_xflag = Flag(FXTRACE);
640 		Flag(FXTRACE) = tp->flag & TRACE ? TRUE : FALSE;
641 
642 		old_inuse = tp->flag & FINUSE;
643 		tp->flag |= FINUSE;
644 
645 		e->type = E_FUNC;
646 		i = ksh_sigsetjmp(e->jbuf, 0);
647 		if (i == 0) {
648 			/* seems odd to pass XERROK here, but at&t ksh does */
649 			exstat = execute(tp->val.t, flags & XERROK);
650 			i = LRETURN;
651 		}
652 		kshname = old_kshname;
653 		Flag(FXTRACE) = old_xflag;
654 		tp->flag = (tp->flag & ~FINUSE) | old_inuse;
655 		/* Were we deleted while executing?  If so, free the execution
656 		 * tree.  todo: Unfortunately, the table entry is never re-used
657 		 * until the lookup table is expanded.
658 		 */
659 		if ((tp->flag & (FDELETE|FINUSE)) == FDELETE) {
660 			if (tp->flag & ALLOC) {
661 				tp->flag &= ~ALLOC;
662 				tfree(tp->val.t, tp->areap);
663 			}
664 			tp->flag = 0;
665 		}
666 		switch (i) {
667 		  case LRETURN:
668 		  case LERROR:
669 			rv = exstat;
670 			break;
671 		  case LINTR:
672 		  case LEXIT:
673 		  case LLEAVE:
674 		  case LSHELL:
675 			quitenv();
676 			unwind(i);
677 			/*NOTREACHED*/
678 		  default:
679 			quitenv();
680 			internal_errorf(1, "CFUNC %d", i);
681 		}
682 		break;
683 	  }
684 
685 	  case CEXEC:		/* executable command */
686 	  case CTALIAS:		/* tracked alias */
687 		if (!(tp->flag&ISSET)) {
688 			/* errno_ will be set if the named command was found
689 			 * but could not be executed (permissions, no execute
690 			 * bit, directory, etc).  Print out a (hopefully)
691 			 * useful error message and set the exit status to 126.
692 			 */
693 			if (tp->u2.errno_) {
694 				warningf(TRUE, "%s: cannot execute - %s", cp,
695 					strerror(tp->u2.errno_));
696 				rv = 126;	/* POSIX */
697 			} else {
698 				warningf(TRUE, "%s: not found", cp);
699 				rv = 127;
700 			}
701 			break;
702 		}
703 
704 		/* set $_ to program's full path */
705 		setstr(typeset("_", LOCAL|EXPORT, 0, 0, 0), tp->val.s);
706 
707 		if (flags&XEXEC) {
708 			j_exit();
709 			if (!(flags&XBGND) || Flag(FMONITOR)) {
710 				setexecsig(&sigtraps[SIGINT], SS_RESTORE_ORIG);
711 				setexecsig(&sigtraps[SIGQUIT], SS_RESTORE_ORIG);
712 			}
713 		}
714 
715 		/* to fork we set up a TEXEC node and call execute */
716 		texec.type = TEXEC;
717 		texec.left = t;	/* for tprint */
718 		texec.str = tp->val.s;
719 		texec.args = ap;
720 		rv = exchild(&texec, flags, -1);
721 		break;
722 	}
723   Leave:
724 	if (flags & XEXEC) {
725 		exstat = rv;
726 		unwind(LLEAVE);
727 	}
728 	return rv;
729 }
730 
731 static void
732 scriptexec(tp, ap)
733 	register struct op *tp;
734 	register char **ap;
735 {
736 	char *shell;
737 
738 	shell = str_val(global(EXECSHELL_STR));
739 	if (shell && *shell)
740 		shell = search(shell, path, X_OK, (int *) 0);
741 	if (!shell || !*shell)
742 		shell = EXECSHELL;
743 
744 	*tp->args-- = tp->str;
745 #ifdef	SHARPBANG
746 	{
747 		char buf[LINE];
748 		register char *cp;
749 		register int fd, n;
750 
751 		buf[0] = '\0';
752 		if ((fd = open(tp->str, O_RDONLY)) >= 0) {
753 			if ((n = read(fd, buf, LINE - 1)) > 0)
754 				buf[n] = '\0';
755 			(void) close(fd);
756 		}
757 		if ((buf[0] == '#' && buf[1] == '!' && (cp = &buf[2]))
758 # ifdef OS2
759 		    || (strncmp(buf, "extproc", 7) == 0 && isspace(buf[7])
760 			&& (cp = &buf[7]))
761 # endif /* OS2 */
762 		    )
763 		{
764 			while (*cp && (*cp == ' ' || *cp == '\t'))
765 				cp++;
766 			if (*cp && *cp != '\n') {
767 				char *a0 = cp, *a1 = (char *) 0;
768 # ifdef OS2
769 				char *a2 = cp;
770 # endif /* OS2 */
771 
772 				while (*cp && *cp != '\n' && *cp != ' '
773 				       && *cp != '\t')
774 				{
775 # ifdef OS2
776 			/* Allow shell search without prepended path
777 			 * if shell with / in pathname cannot be found.
778 			 * Use / explicitly so \ can be used if explicit
779 			 * needs to be forced.
780 			 */
781 					if (*cp == '/')
782 						a2 = cp + 1;
783 # endif /* OS2 */
784 					cp++;
785 				}
786 				if (*cp && *cp != '\n') {
787 					*cp++ = '\0';
788 					while (*cp
789 					       && (*cp == ' ' || *cp == '\t'))
790 						cp++;
791 					if (*cp && *cp != '\n') {
792 						a1 = cp;
793 						/* all one argument */
794 						while (*cp && *cp != '\n')
795 							cp++;
796 					}
797 				}
798 				if (*cp == '\n') {
799 					*cp = '\0';
800 					if (a1)
801 						*tp->args-- = a1;
802 # ifdef OS2
803 					if (a0 != a2 && search_access(a0, X_OK, (int *) 0))
804 						a0 = a2;
805 # endif /* OS2 */
806 					shell = a0;
807 				}
808 			}
809 # ifdef OS2
810 		} else {
811 		        /* Use ksh documented shell default if present
812 			 * else use OS2_SHELL which is assumed to need
813 			 * the /c option and '\' as dir separater.
814 			 */
815 		         char *p = shell;
816 
817 			 shell = str_val(global("EXECSHELL"));
818 			 if (shell && *shell)
819 				 shell = search(shell, path, X_OK, (int *) 0);
820 			 if (!shell || !*shell) {
821 				 shell = p;
822 				 *tp->args-- = "/c";
823 				 for (p = tp->str; *p; p++)
824 					 if (*p == '/')
825 						 *p = '\\';
826 			 }
827 # endif /* OS2 */
828 		}
829 	}
830 #endif	/* SHARPBANG */
831 	*tp->args = shell;
832 
833 	ksh_execve(tp->args[0], tp->args, ap);
834 
835 	/* report both the program that was run and the bogus shell */
836 	errorf("%s: %s: %s", tp->str, shell, strerror(errno));
837 }
838 
839 int
840 shcomexec(wp)
841 	register char **wp;
842 {
843 	register struct tbl *tp;
844 
845 	tp = tsearch(&builtins, *wp, hash(*wp));
846 	if (tp == NULL)
847 		internal_errorf(1, "shcomexec: %s", *wp);
848 	return call_builtin(tp, wp);
849 }
850 
851 /*
852  * Search function tables for a function.  If create set, a table entry
853  * is created if none is found.
854  */
855 struct tbl *
856 findfunc(name, h, create)
857 	const char *name;
858 	unsigned int	h;
859 	int	create;
860 {
861 	struct block *l;
862 	struct tbl *tp = (struct tbl *) 0;
863 
864 	for (l = e->loc; l; l = l->next) {
865 		tp = tsearch(&l->funs, name, h);
866 		if (tp)
867 			break;
868 		if (!l->next && create) {
869 			tp = tenter(&l->funs, name, h);
870 			tp->flag = DEFINED;
871 			tp->type = CFUNC;
872 			tp->val.t = (struct op *) 0;
873 			break;
874 		}
875 	}
876 	return tp;
877 }
878 
879 /*
880  * define function.  Returns 1 if function is being undefined (t == 0) and
881  * function did not exist, returns 0 otherwise.
882  */
883 int
884 define(name, t)
885 	const char *name;
886 	struct op *t;
887 {
888 	struct tbl *tp;
889 	int was_set = 0;
890 
891 	while (1) {
892 		tp = findfunc(name, hash(name), TRUE);
893 
894 		if (tp->flag & ISSET)
895 			was_set = 1;
896 		/* If this function is currently being executed, we zap this
897 		 * table entry so findfunc() won't see it
898 		 */
899 		if (tp->flag & FINUSE) {
900 			tp->name[0] = '\0';
901 			tp->flag &= ~DEFINED; /* ensure it won't be found */
902 			tp->flag |= FDELETE;
903 		} else
904 			break;
905 	}
906 
907 	if (tp->flag & ALLOC) {
908 		tp->flag &= ~(ISSET|ALLOC);
909 		tfree(tp->val.t, tp->areap);
910 	}
911 
912 	if (t == NULL) {		/* undefine */
913 		tdelete(tp);
914 		return was_set ? 0 : 1;
915 	}
916 
917 	tp->val.t = tcopy(t->left, tp->areap);
918 	tp->flag |= (ISSET|ALLOC);
919 	if (t->u.ksh_func)
920 	    tp->flag |= FKSH;
921 
922 	return 0;
923 }
924 
925 /*
926  * add builtin
927  */
928 void
929 builtin(name, func)
930 	const char *name;
931 	int (*func) ARGS((char **));
932 {
933 	register struct tbl *tp;
934 	Tflag flag;
935 
936 	/* see if any flags should be set for this builtin */
937 	for (flag = 0; ; name++) {
938 		if (*name == '=')	/* command does variable assignment */
939 			flag |= KEEPASN;
940 		else if (*name == '*')	/* POSIX special builtin */
941 			flag |= SPEC_BI;
942 		else if (*name == '+')	/* POSIX regular builtin */
943 			flag |= REG_BI;
944 		else
945 			break;
946 	}
947 
948 	tp = tenter(&builtins, name, hash(name));
949 	tp->flag = DEFINED | flag;
950 	tp->type = CSHELL;
951 	tp->val.f = func;
952 }
953 
954 /*
955  * find command
956  * either function, hashed command, or built-in (in that order)
957  */
958 struct tbl *
959 findcom(name, flags)
960 	const char *name;
961 	int	flags;		/* FC_* */
962 {
963 	static struct tbl temp;
964 	unsigned int h = hash(name);
965 	struct tbl *tp = NULL, *tbi;
966 	int insert = Flag(FTRACKALL);	/* insert if not found */
967 	char *fpath;			/* for function autoloading */
968 	char *npath;
969 
970 	if (ksh_strchr_dirsep(name) != NULL) {
971 		insert = 0;
972 		/* prevent FPATH search below */
973 		flags &= ~FC_FUNC;
974 		goto Search;
975 	}
976 	tbi = (flags & FC_BI) ? tsearch(&builtins, name, h) : NULL;
977 	/* POSIX says special builtins first, then functions, then
978 	 * POSIX regular builtins, then search path...
979 	 */
980 	if ((flags & FC_SPECBI) && tbi && (tbi->flag & SPEC_BI))
981 		tp = tbi;
982 	if (!tp && (flags & FC_FUNC)) {
983 		tp = findfunc(name, h, FALSE);
984 		if (tp && !(tp->flag & ISSET)) {
985 			if ((fpath = str_val(global("FPATH"))) == null) {
986 				tp->u.fpath = (char *) 0;
987 				tp->u2.errno_ = 0;
988 			} else
989 				tp->u.fpath = search(name, fpath, R_OK,
990 					&tp->u2.errno_);
991 		}
992 	}
993 	if (!tp && (flags & FC_REGBI) && tbi && (tbi->flag & REG_BI))
994 		tp = tbi;
995 	/* todo: posix says non-special/non-regular builtins must
996 	 * be triggered by some user-controllable means like a
997 	 * special directory in PATH.  Requires modifications to
998 	 * the search() function.  Tracked aliases should be
999 	 * modified to allow tracking of builtin commands.
1000 	 * This should be under control of the FPOSIX flag.
1001 	 * If this is changed, also change c_whence...
1002 	 */
1003 	if (!tp && (flags & FC_UNREGBI) && tbi)
1004 		tp = tbi;
1005 	if (!tp && (flags & FC_PATH) && !(flags & FC_DEFPATH)) {
1006 		tp = tsearch(&taliases, name, h);
1007 		if (tp && (tp->flag & ISSET) && eaccess(tp->val.s, X_OK) != 0) {
1008 			if (tp->flag & ALLOC) {
1009 				tp->flag &= ~ALLOC;
1010 				afree(tp->val.s, APERM);
1011 			}
1012 			tp->flag &= ~ISSET;
1013 		}
1014 	}
1015 
1016   Search:
1017 	if ((!tp || (tp->type == CTALIAS && !(tp->flag&ISSET)))
1018 	    && (flags & FC_PATH))
1019 	{
1020 		if (!tp) {
1021 			if (insert && !(flags & FC_DEFPATH)) {
1022 				tp = tenter(&taliases, name, h);
1023 				tp->type = CTALIAS;
1024 			} else {
1025 				tp = &temp;
1026 				tp->type = CEXEC;
1027 			}
1028 			tp->flag = DEFINED;	/* make ~ISSET */
1029 		}
1030 		npath = search(name, flags & FC_DEFPATH ? def_path : path,
1031 				X_OK, &tp->u2.errno_);
1032 		if (npath) {
1033 			tp->val.s = tp == &temp ? npath : str_save(npath, APERM);
1034 			tp->flag |= ISSET|ALLOC;
1035 		} else if ((flags & FC_FUNC)
1036 			   && (fpath = str_val(global("FPATH"))) != null
1037 			   && (npath = search(name, fpath, R_OK,
1038 					      &tp->u2.errno_)) != (char *) 0)
1039 		{
1040 			/* An undocumented feature of at&t ksh is that it
1041 			 * searches FPATH if a command is not found, even
1042 			 * if the command hasn't been set up as an autoloaded
1043 			 * function (ie, no typeset -uf).
1044 			 */
1045 			tp = &temp;
1046 			tp->type = CFUNC;
1047 			tp->flag = DEFINED; /* make ~ISSET */
1048 			tp->u.fpath = npath;
1049 		}
1050 	}
1051 	return tp;
1052 }
1053 
1054 /*
1055  * flush executable commands with relative paths
1056  */
1057 void
1058 flushcom(all)
1059 	int all;		/* just relative or all */
1060 {
1061 	struct tbl *tp;
1062 	struct tstate ts;
1063 
1064 	for (twalk(&ts, &taliases); (tp = tnext(&ts)) != NULL; )
1065 		if ((tp->flag&ISSET) && (all || !ISDIRSEP(tp->val.s[0]))) {
1066 			if (tp->flag&ALLOC) {
1067 				tp->flag &= ~(ALLOC|ISSET);
1068 				afree(tp->val.s, APERM);
1069 			}
1070 			tp->flag = ~ISSET;
1071 		}
1072 }
1073 
1074 /* Check if path is something we want to find.  Returns -1 for failure. */
1075 int
1076 search_access(path, mode, errnop)
1077 	const char *path;
1078 	int mode;
1079 	int *errnop;		/* set if candidate found, but not suitable */
1080 {
1081 #ifndef OS2
1082 	int ret, err = 0;
1083 	struct stat statb;
1084 
1085 	if (stat(path, &statb) < 0)
1086 		return -1;
1087 	ret = eaccess(path, mode);
1088 	if (ret < 0)
1089 		err = errno; /* File exists, but we can't access it */
1090 	else if (mode == X_OK && (!S_ISREG(statb.st_mode)
1091 		   /* This 'cause access() says root can execute everything */
1092 		   || !(statb.st_mode & (S_IXUSR|S_IXGRP|S_IXOTH))))
1093 	{
1094 		ret = -1;
1095 		err = S_ISDIR(statb.st_mode) ? EISDIR : EACCES;
1096 	}
1097 	if (err && errnop)
1098 		*errnop = err;
1099 	return ret;
1100 #else /* !OS2 */
1101 	/*
1102 	 * NOTE: ASSUMES path can be modified and has enough room at the
1103 	 *       end of the string for a suffix (ie, 4 extra characters).
1104 	 *	 Certain code knows this (eg, eval.c(globit()),
1105 	 *	 exec.c(search())).
1106 	 */
1107 	static char *xsuffixes[] = { ".ksh", ".exe", ".", ".sh", ".cmd",
1108 				     ".com", ".bat", (char *) 0
1109 				   };
1110 	static char *rsuffixes[] = { ".ksh", ".", ".sh", ".cmd", ".bat",
1111 				      (char *) 0
1112 				   };
1113 	int i;
1114 	char *mpath = (char *) path;
1115 	char *tp = mpath + strlen(mpath);
1116 	char *p;
1117 	char **sfx;
1118 
1119 	/* If a suffix has been specified, check if it is one of the
1120 	 * suffixes that indicate the file is executable - if so, change
1121 	 * the access test to R_OK...
1122 	 * This code assumes OS/2 files can have only one suffix...
1123 	 */
1124 	if ((p = strrchr((p = ksh_strrchr_dirsep(mpath)) ? p : mpath, '.'))) {
1125 		if (mode == X_OK)
1126 			mode = R_OK;
1127 		return search_access1(mpath, mode, errnop);
1128 	}
1129 	/* Try appending the various suffixes.  Different suffixes for
1130 	 * read and execute 'cause we don't want to read an executable...
1131 	 */
1132 	sfx = mode == R_OK ? rsuffixes : xsuffixes;
1133 	for (i = 0; sfx[i]; i++) {
1134 		strcpy(tp, p = sfx[i]);
1135 		if (search_access1(mpath, R_OK, errnop) == 0)
1136 			return 0;
1137 		*tp = '\0';
1138 	}
1139 	return -1;
1140 #endif /* !OS2 */
1141 }
1142 
1143 #ifdef OS2
1144 static int
1145 search_access1(path, mode, errnop)
1146 	const char *path;
1147 	int mode;
1148 	int *errnop;		/* set if candidate found, but not suitable */
1149 {
1150 	int ret, err = 0;
1151 	struct stat statb;
1152 
1153 	if (stat(path, &statb) < 0)
1154 		return -1;
1155 	ret = eaccess(path, mode);
1156 	if (ret < 0)
1157 		err = errno; /* File exists, but we can't access it */
1158 	else if (!S_ISREG(statb.st_mode)) {
1159 		ret = -1;
1160 		err = S_ISDIR(statb.st_mode) ? EISDIR : EACCES;
1161 	}
1162 	if (err && errnop)
1163 		*errnop = err;
1164 	return ret;
1165 }
1166 #endif /* OS2 */
1167 
1168 /*
1169  * search for command with PATH
1170  */
1171 char *
1172 search(name, path, mode, errnop)
1173 	const char *name;
1174 	const char *path;
1175 	int mode;		/* R_OK or X_OK */
1176 	int *errnop;		/* set if candidate found, but not suitable */
1177 {
1178 	const char *sp, *p;
1179 	char *xp;
1180 	XString xs;
1181 	int namelen;
1182 
1183 	if (errnop)
1184 		*errnop = 0;
1185 #ifdef OS2
1186 	/* Xinit() allocates 8 additional bytes, so appended suffixes won't
1187 	 * overflow the memory.
1188 	 */
1189 	namelen = strlen(name) + 1;
1190 	Xinit(xs, xp, namelen, ATEMP);
1191 	memcpy(Xstring(xs, xp), name, namelen);
1192 
1193  	if (ksh_strchr_dirsep(name)) {
1194 		if (search_access(Xstring(xs, xp), mode, errnop) >= 0)
1195 			return Xstring(xs, xp); /* not Xclose() - see above */
1196 		Xfree(xs, xp);
1197 		return NULL;
1198 	}
1199 
1200 	/* Look in current context always. (os2 style) */
1201 	if (search_access(Xstring(xs, xp), mode, errnop) == 0)
1202 		return Xstring(xs, xp); /* not Xclose() - xp may be wrong */
1203 #else /* OS2 */
1204 	if (ksh_strchr_dirsep(name)) {
1205 		if (search_access(name, mode, errnop) == 0)
1206 			return (char *) name;
1207 		return NULL;
1208 	}
1209 
1210 	namelen = strlen(name) + 1;
1211 	Xinit(xs, xp, 128, ATEMP);
1212 #endif /* OS2 */
1213 
1214 	sp = path;
1215 	while (sp != NULL) {
1216 		xp = Xstring(xs, xp);
1217 		if (!(p = strchr(sp, PATHSEP)))
1218 			p = sp + strlen(sp);
1219 		if (p != sp) {
1220 			XcheckN(xs, xp, p - sp);
1221 			memcpy(xp, sp, p - sp);
1222 			xp += p - sp;
1223 			*xp++ = DIRSEP;
1224 		}
1225 		sp = p;
1226 		XcheckN(xs, xp, namelen);
1227 		memcpy(xp, name, namelen);
1228  		if (search_access(Xstring(xs, xp), mode, errnop) == 0)
1229 #ifdef OS2
1230  			return Xstring(xs, xp); /* Not Xclose() - see above */
1231 #else /* OS2 */
1232 			return Xclose(xs, xp + namelen);
1233 #endif /* OS2 */
1234 		if (*sp++ == '\0')
1235 			sp = NULL;
1236 	}
1237 	Xfree(xs, xp);
1238 	return NULL;
1239 }
1240 
1241 static int
1242 call_builtin(tp, wp)
1243 	struct tbl *tp;
1244 	char **wp;
1245 {
1246 	int rv;
1247 
1248 	builtin_argv0 = wp[0];
1249 	builtin_flag = tp->flag;
1250 	shf_reopen(1, SHF_WR, shl_stdout);
1251 	shl_stdout_ok = 1;
1252 	ksh_getopt_reset(&builtin_opt, GF_ERROR);
1253 	rv = (*tp->val.f)(wp);
1254 	shf_flush(shl_stdout);
1255 	shl_stdout_ok = 0;
1256 	builtin_flag = 0;
1257 	builtin_argv0 = (char *) 0;
1258 	return rv;
1259 }
1260 
1261 /*
1262  * set up redirection, saving old fd's in e->savefd
1263  */
1264 static int
1265 iosetup(iop, tp)
1266 	register struct ioword *iop;
1267 	struct tbl *tp;
1268 {
1269 	register int u = -1;
1270 	char *cp = iop->name;
1271 	int iotype = iop->flag & IOTYPE;
1272 	int do_open = 1, do_close = 0, UNINITIALIZED(flags);
1273 	struct ioword iotmp;
1274 	struct stat statb;
1275 
1276 	if (iotype != IOHERE)
1277 		cp = evalonestr(cp, DOTILDE|(Flag(FTALKING) ? DOGLOB : 0));
1278 
1279 	/* Used for tracing and error messages to print expanded cp */
1280 	iotmp = *iop;
1281 	iotmp.name = (iotype == IOHERE) ? (char *) 0 : cp;
1282 	iotmp.flag |= IONAMEXP;
1283 
1284 	if (Flag(FXTRACE))
1285 		shellf("%s%s\n",
1286 			PS4_SUBSTITUTE(str_val(global("PS4"))),
1287 			snptreef((char *) 0, 32, "%R", &iotmp));
1288 
1289 	switch (iotype) {
1290 	  case IOREAD:
1291 		flags = O_RDONLY;
1292 		break;
1293 
1294 	  case IOCAT:
1295 		flags = O_WRONLY | O_APPEND | O_CREAT;
1296 		break;
1297 
1298 	  case IOWRITE:
1299 		flags = O_WRONLY | O_CREAT | O_TRUNC;
1300 		if (Flag(FNOCLOBBER) && !(iop->flag & IOCLOB)
1301 		    && (stat(cp, &statb) < 0 || S_ISREG(statb.st_mode)))
1302 			flags |= O_EXCL;
1303 		break;
1304 
1305 	  case IORDWR:
1306 		flags = O_RDWR | O_CREAT;
1307 		break;
1308 
1309 	  case IOHERE:
1310 		do_open = 0;
1311 		/* herein() returns -2 if error has been printed */
1312 		u = herein(cp, iop->flag & IOEVAL);
1313 		/* cp may have wrong name */
1314 		break;
1315 
1316 	  case IODUP:
1317 	  {
1318 		const char *emsg;
1319 
1320 		do_open = 0;
1321 		if (*cp == '-' && !cp[1]) {
1322 			u = 1009;	 /* prevent error return below */
1323 			do_close = 1;
1324 		} else if ((u = check_fd(cp,
1325 				X_OK | ((iop->flag & IORDUP) ? R_OK : W_OK),
1326 				&emsg)) < 0)
1327 		{
1328 			warningf(TRUE, "%s: %s",
1329 				snptreef((char *) 0, 32, "%R", &iotmp), emsg);
1330 			return -1;
1331 		}
1332 		break;
1333 	  }
1334 	}
1335 	if (do_open) {
1336 		if (Flag(FRESTRICTED) && (flags & O_CREAT)) {
1337 			warningf(TRUE, "%s: restricted", cp);
1338 			return -1;
1339 		}
1340 		u = open(cp, flags, 0666);
1341 #ifdef OS2
1342 		if (u < 0 && strcmp(cp, "/dev/null") == 0)
1343 			u = open("nul", flags, 0666);
1344 #endif /* OS2 */
1345 	}
1346 	if (u < 0) {
1347 		/* herein() may already have printed message */
1348 		if (u == -1)
1349 			warningf(TRUE, "cannot %s %s: %s",
1350 			       iotype == IODUP ? "dup"
1351 				: (iotype == IOREAD || iotype == IOHERE) ?
1352 				    "open" : "create", cp, strerror(errno));
1353 		return -1;
1354 	}
1355 	/* Do not save if it has already been redirected (i.e. "cat >x >y"). */
1356 	if (e->savefd[iop->unit] == 0)
1357 		/* c_exec() assumes e->savefd[fd] set for any redirections.
1358 		 * Ask savefd() not to close iop->unit - allows error messages
1359 		 * to be seen if iop->unit is 2; also means we can't lose
1360 		 * the fd (eg, both dup2 below and dup2 in restfd() failing).
1361 		 */
1362 		e->savefd[iop->unit] = savefd(iop->unit, 1);
1363 
1364 	if (do_close)
1365 		close(iop->unit);
1366 	else if (u != iop->unit) {
1367 		if (ksh_dup2(u, iop->unit, TRUE) < 0) {
1368 			warningf(TRUE,
1369 				"could not finish (dup) redirection %s: %s",
1370 				snptreef((char *) 0, 32, "%R", &iotmp),
1371 				strerror(errno));
1372 			if (iotype != IODUP)
1373 				close(u);
1374 			return -1;
1375 		}
1376 		if (iotype != IODUP)
1377 			close(u);
1378 #ifdef KSH
1379 		/* Touching any co-process fd in an empty exec
1380 		 * causes the shell to close its copies
1381 		 */
1382 		else if (tp && tp->type == CSHELL && tp->val.f == c_exec) {
1383 			if (iop->flag & IORDUP)	/* possible exec <&p */
1384 				coproc_read_close(u);
1385 			else			/* possible exec >&p */
1386 				coproc_write_close(u);
1387 		}
1388 #endif /* KSH */
1389 	}
1390 	if (u == 2) /* Clear any write errors */
1391 		shf_reopen(2, SHF_WR, shl_out);
1392 	return 0;
1393 }
1394 
1395 /*
1396  * open here document temp file.
1397  * if unquoted here, expand here temp file into second temp file.
1398  */
1399 static int
1400 herein(hname, sub)
1401 	char *hname;
1402 	int sub;
1403 {
1404 	int fd;
1405 
1406 	/* ksh -c 'cat << EOF' can cause this... */
1407 	if (hname == (char *) 0) {
1408 		warningf(TRUE, "here document missing");
1409 		return -2; /* special to iosetup(): don't print error */
1410 	}
1411 	if (sub) {
1412 		char *cp;
1413 		struct source *s, *volatile osource = source;
1414 		struct temp *h;
1415 		struct shf *volatile shf;
1416 		int i;
1417 
1418 		/* must be before newenv() 'cause shf uses ATEMP */
1419 		shf = shf_open(hname, O_RDONLY, 0, SHF_MAPHI|SHF_CLEXEC);
1420 		if (shf == NULL)
1421 			return -1;
1422 		newenv(E_ERRH);
1423 		i = ksh_sigsetjmp(e->jbuf, 0);
1424 		if (i) {
1425 			if (shf)
1426 				shf_close(shf);
1427 			source = osource;
1428 			quitenv(); /* after shf_close() due to alloc */
1429 			return -2; /* special to iosetup(): don't print error */
1430 		}
1431 		/* set up yylex input from here file */
1432 		s = pushs(SFILE, ATEMP);
1433 		s->u.shf = shf;
1434 		source = s;
1435 		if (yylex(ONEWORD) != LWORD)
1436 			internal_errorf(1, "herein: yylex");
1437 		shf_close(shf);
1438 		shf = (struct shf *) 0;
1439 		cp = evalstr(yylval.cp, 0);
1440 
1441 		/* write expanded input to another temp file */
1442 		h = maketemp(ATEMP);
1443 		h->next = e->temps; e->temps = h;
1444 		if (!(shf = h->shf) || (fd = open(h->name, O_RDONLY, 0)) < 0)
1445 			/* shf closeed by error handler */
1446 			errorf("%s: %s", h->name, strerror(errno));
1447 		shf_puts(cp, shf);
1448 		if (shf_close(shf) == EOF) {
1449 			close(fd);
1450 			shf = (struct shf *) 0;
1451 			errorf("error writing %s: %s", h->name,
1452 				strerror(errno));
1453 		}
1454 		shf = (struct shf *) 0;
1455 
1456 		quitenv();
1457 	} else {
1458 		fd = open(hname, O_RDONLY, 0);
1459 		if (fd < 0)
1460 			return -1;
1461 	}
1462 
1463 	return fd;
1464 }
1465 
1466 #ifdef KSH
1467 /*
1468  *	ksh special - the select command processing section
1469  *	print the args in column form - assuming that we can
1470  */
1471 static char *
1472 do_selectargs(ap, print_menu)
1473 	register char **ap;
1474 	bool_t print_menu;
1475 {
1476 	static const char *const read_args[] = {
1477 					"read", "-r", "REPLY", (char *) 0
1478 				    };
1479 	char *s;
1480 	int i, argct;
1481 
1482 	for (argct = 0; ap[argct]; argct++)
1483 		;
1484 	while (1) {
1485 		/* Menu is printed if
1486 		 *	- this is the first time around the select loop
1487 		 *	- the user enters a blank line
1488 		 *	- the REPLY parameter is empty
1489 		 */
1490 		if (print_menu || !*str_val(global("REPLY")))
1491 			pr_menu(ap);
1492 		shellf("%s", str_val(global("PS3")));
1493 		if (call_builtin(findcom("read", FC_BI), (char **) read_args))
1494 			return (char *) 0;
1495 		s = str_val(global("REPLY"));
1496 		if (*s) {
1497 			i = atoi(s);
1498 			return (i >= 1 && i <= argct) ? ap[i - 1] : null;
1499 		}
1500 		print_menu = 1;
1501 	}
1502 }
1503 
1504 struct select_menu_info {
1505 	char	*const *args;
1506 	int	arg_width;
1507 	int	num_width;
1508 } info;
1509 
1510 static char *select_fmt_entry ARGS((void *arg, int i, char *buf, int buflen));
1511 
1512 /* format a single select menu item */
1513 static char *
1514 select_fmt_entry(arg, i, buf, buflen)
1515 	void *arg;
1516 	int i;
1517 	char *buf;
1518 	int buflen;
1519 {
1520 	struct select_menu_info *smi = (struct select_menu_info *) arg;
1521 
1522 	shf_snprintf(buf, buflen, "%*d) %s",
1523 		smi->num_width, i + 1, smi->args[i]);
1524 	return buf;
1525 }
1526 
1527 /*
1528  *	print a select style menu
1529  */
1530 int
1531 pr_menu(ap)
1532 	char *const *ap;
1533 {
1534 	struct select_menu_info smi;
1535 	char *const *pp;
1536 	int nwidth, dwidth;
1537 	int i, n;
1538 
1539 	/* Width/column calculations were done once and saved, but this
1540 	 * means select can't be used recursively so we re-calculate each
1541 	 * time (could save in a structure that is returned, but its probably
1542 	 * not worth the bother).
1543 	 */
1544 
1545 	/*
1546 	 * get dimensions of the list
1547 	 */
1548 	for (n = 0, nwidth = 0, pp = ap; *pp; n++, pp++) {
1549 		i = strlen(*pp);
1550 		nwidth = (i > nwidth) ? i : nwidth;
1551 	}
1552 	/*
1553 	 * we will print an index of the form
1554 	 *	%d)
1555 	 * in front of each entry
1556 	 * get the max width of this
1557 	 */
1558 	for (i = n, dwidth = 1; i >= 10; i /= 10)
1559 		dwidth++;
1560 
1561 	smi.args = ap;
1562 	smi.arg_width = nwidth;
1563 	smi.num_width = dwidth;
1564 	print_columns(shl_out, n, select_fmt_entry, (void *) &smi,
1565 		dwidth + nwidth + 2);
1566 
1567 	return n;
1568 }
1569 #endif /* KSH */
1570 #ifdef KSH
1571 
1572 /*
1573  *	[[ ... ]] evaluation routines
1574  */
1575 
1576 extern const char *const dbtest_tokens[];
1577 extern const char db_close[];
1578 
1579 /* Test if the current token is a whatever.  Accepts the current token if
1580  * it is.  Returns 0 if it is not, non-zero if it is (in the case of
1581  * TM_UNOP and TM_BINOP, the returned value is a Test_op).
1582  */
1583 static int
1584 dbteste_isa(te, meta)
1585 	Test_env *te;
1586 	Test_meta meta;
1587 {
1588 	int ret = 0;
1589 	int uqword;
1590 	char *p;
1591 
1592 	if (!*te->pos.wp)
1593 		return meta == TM_END;
1594 
1595 	/* unquoted word? */
1596 	for (p = *te->pos.wp; *p == CHAR; p += 2)
1597 		;
1598 	uqword = *p == EOS;
1599 
1600 	if (meta == TM_UNOP || meta == TM_BINOP) {
1601 		if (uqword) {
1602 			char buf[8];	/* longer than the longest operator */
1603 			char *q = buf;
1604 			for (p = *te->pos.wp; *p == CHAR
1605 					      && q < &buf[sizeof(buf) - 1];
1606 					      p += 2)
1607 				*q++ = p[1];
1608 			*q = '\0';
1609 			ret = (int) test_isop(te, meta, buf);
1610 		}
1611 	} else if (meta == TM_END)
1612 		ret = 0;
1613 	else
1614 		ret = uqword
1615 			&& strcmp(*te->pos.wp, dbtest_tokens[(int) meta]) == 0;
1616 
1617 	/* Accept the token? */
1618 	if (ret)
1619 		te->pos.wp++;
1620 
1621 	return ret;
1622 }
1623 
1624 static const char *
1625 dbteste_getopnd(te, op, do_eval)
1626 	Test_env *te;
1627 	Test_op op;
1628 	int do_eval;
1629 {
1630 	char *s = *te->pos.wp;
1631 
1632 	if (!s)
1633 		return (char *) 0;
1634 
1635 	te->pos.wp++;
1636 
1637 	if (!do_eval)
1638 		return null;
1639 
1640 	if (op == TO_STEQL || op == TO_STNEQ)
1641 		s = evalstr(s, DOTILDE | DOPAT);
1642 	else
1643 		s = evalstr(s, DOTILDE);
1644 
1645 	return s;
1646 }
1647 
1648 static int
1649 dbteste_eval(te, op, opnd1, opnd2, do_eval)
1650 	Test_env *te;
1651 	Test_op op;
1652 	const char *opnd1;
1653 	const char *opnd2;
1654 	int do_eval;
1655 {
1656 	return test_eval(te, op, opnd1, opnd2, do_eval);
1657 }
1658 
1659 static void
1660 dbteste_error(te, offset, msg)
1661 	Test_env *te;
1662 	int offset;
1663 	const char *msg;
1664 {
1665 	te->flags |= TEF_ERROR;
1666 	internal_errorf(0, "dbteste_error: %s (offset %d)", msg, offset);
1667 }
1668 #endif /* KSH */
1669