xref: /netbsd-src/bin/ksh/exec.c (revision bada23909e740596d0a3785a73bd3583a9807fb8)
1 /*	$NetBSD: exec.c,v 1.4 1998/07/28 05:31:25 mycroft 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 		/* NOTREACHED */
434 	}
435 	if (rv != 0 && !(flags & XERROK)) {
436 		if (Flag(FERREXIT))
437 			unwind(LERROR);
438 		trapsig(SIGERR_);
439 	}
440 	return rv;
441 }
442 
443 /*
444  * execute simple command
445  */
446 
447 static int
448 comexec(t, tp, ap, flags)
449 	struct op *t;
450 	struct tbl *volatile tp;
451 	register char **ap;
452 	int volatile flags;
453 {
454 	int i;
455 	int rv = 0;
456 	register char *cp;
457 	register char **lastp;
458 	static struct op texec; /* Must be static (XXX but why?) */
459 	int type_flags;
460 	int keepasn_ok;
461 	int fcflags = FC_BI|FC_FUNC|FC_PATH;
462 #ifdef __GNUC__
463 	(void) &rv;
464 #endif
465 
466 	/* snag the last argument for $_ XXX not the same as at&t ksh,
467 	 * which only seems to set $_ after a newline (but not in
468 	 * functions/dot scripts, but in interactive and scipt) -
469 	 * perhaps save last arg here and set it in shell()?.
470 	 */
471 	if (*(lastp = ap)) {
472 		while (*++lastp)
473 			;
474 		setstr(typeset("_", LOCAL, 0, 0, 0), *--lastp);
475 	}
476 
477 	/* Deal with the shell builtins builtin, exec and command since
478 	 * they can be followed by other commands.  This must be done before
479 	 * we know if we should create a local block, which must be done
480 	 * before we can do a path search (in case the assignments change
481 	 * PATH).
482 	 * Odd cases:
483 	 *   FOO=bar exec > /dev/null		FOO is kept but not exported
484 	 *   FOO=bar exec foobar		FOO is exported
485 	 *   FOO=bar command exec > /dev/null	FOO is neither kept nor exported
486 	 *   FOO=bar command			FOO is neither kept nor exported
487 	 *   PATH=... foobar			use new PATH in foobar search
488 	 */
489 	keepasn_ok = 1;
490 	while (tp && tp->type == CSHELL) {
491 		fcflags = FC_BI|FC_FUNC|FC_PATH;/* undo effects of command */
492 		if (tp->val.f == c_builtin) {
493 			if ((cp = *++ap) == NULL) {
494 				tp = NULL;
495 				break;
496 			}
497 			tp = findcom(cp, FC_BI);
498 			if (tp == NULL)
499 				errorf("builtin: %s: not a builtin", cp);
500 			continue;
501 		} else if (tp->val.f == c_exec) {
502 			if (ap[1] == NULL)
503 				break;
504 			ap++;
505 			flags |= XEXEC;
506 		} else if (tp->val.f == c_command) {
507 			int optc, saw_p = 0;
508 
509 			/* Ugly dealing with options in two places (here and
510 			 * in c_command(), but such is life)
511 			 */
512 			ksh_getopt_reset(&builtin_opt, 0);
513 			while ((optc = ksh_getopt(ap, &builtin_opt, ":p"))
514 									== 'p')
515 				saw_p = 1;
516 			if (optc != EOF)
517 				break;	/* command -vV or something */
518 			/* don't look for functions */
519 			fcflags = FC_BI|FC_PATH;
520 			if (saw_p) {
521 				if (Flag(FRESTRICTED)) {
522 					warningf(TRUE,
523 						"command -p: restricted");
524 					rv = 1;
525 					goto Leave;
526 				}
527 				fcflags |= FC_DEFPATH;
528 			}
529 			ap += builtin_opt.optind;
530 			/* POSIX says special builtins lose their status
531 			 * if accessed using command.
532 			 */
533 			keepasn_ok = 0;
534 			if (!ap[0]) {
535 				/* ensure command with no args exits with 0 */
536 				subst_exstat = 0;
537 				break;
538 			}
539 		} else
540 			break;
541 		tp = findcom(ap[0], fcflags & (FC_BI|FC_FUNC));
542 	}
543 	if (keepasn_ok && (!ap[0] || (tp && (tp->flag & KEEPASN))))
544 		type_flags = 0;
545 	else {
546 		/* create new variable/function block */
547 		newblock();
548 		/* ksh functions don't keep assignments, POSIX functions do. */
549 		if (keepasn_ok && tp && tp->type == CFUNC
550 		    && !(tp->flag & FKSH))
551 			type_flags = 0;
552 		else
553 			type_flags = LOCAL|LOCAL_COPY|EXPORT;
554 	}
555 	if (Flag(FEXPORT))
556 		type_flags |= EXPORT;
557 	for (i = 0; t->vars[i]; i++) {
558 		cp = evalstr(t->vars[i], DOASNTILDE);
559 		if (Flag(FXTRACE)) {
560 			if (i == 0)
561 				shf_fprintf(shl_out, "%s",
562 					PS4_SUBSTITUTE(str_val(global("PS4"))));
563 			shf_fprintf(shl_out, "%s%s", cp,
564 				t->vars[i + 1] ? space : newline);
565 			if (!t->vars[i + 1])
566 				shf_flush(shl_out);
567 		}
568 		typeset(cp, type_flags, 0, 0, 0);
569 	}
570 
571 	if ((cp = *ap) == NULL) {
572 		rv = subst_exstat;
573 		goto Leave;
574 	} else if (!tp) {
575 		if (Flag(FRESTRICTED) && ksh_strchr_dirsep(cp)) {
576 			warningf(TRUE, "%s: restricted", cp);
577 			rv = 1;
578 			goto Leave;
579 		}
580 		tp = findcom(cp, fcflags);
581 	}
582 
583 	switch (tp->type) {
584 	  case CSHELL:			/* shell built-in */
585 		rv = call_builtin(tp, ap);
586 		break;
587 
588 	  case CFUNC:			/* function call */
589 	  {
590 		volatile int old_xflag;
591 		volatile Tflag old_inuse;
592 		const char *volatile old_kshname;
593 
594 		if (!(tp->flag & ISSET)) {
595 			struct tbl *ftp;
596 
597 			if (!tp->u.fpath) {
598 				if (tp->u2.errno_) {
599 					warningf(TRUE,
600 				"%s: can't find function definition file - %s",
601 						cp, strerror(tp->u2.errno_));
602 					rv = 126;
603 				} else {
604 					warningf(TRUE,
605 				"%s: can't find function definition file", cp);
606 					rv = 127;
607 				}
608 				break;
609 			}
610 			if (include(tp->u.fpath, 0, (char **) 0, 0) < 0) {
611 				warningf(TRUE,
612 			    "%s: can't open function definition file %s - %s",
613 					cp, tp->u.fpath, strerror(errno));
614 				rv = 127;
615 				break;
616 			}
617 			if (!(ftp = findfunc(cp, hash(cp), FALSE))
618 			    || !(ftp->flag & ISSET))
619 			{
620 				warningf(TRUE,
621 					"%s: function not defined by %s",
622 					cp, tp->u.fpath);
623 				rv = 127;
624 				break;
625 			}
626 			tp = ftp;
627 		}
628 
629 		/* ksh functions set $0 to function name, POSIX functions leave
630 		 * $0 unchanged.
631 		 */
632 		old_kshname = kshname;
633 		if (tp->flag & FKSH)
634 			kshname = ap[0];
635 		e->loc->argv = ap;
636 		for (i = 0; *ap++ != NULL; i++)
637 			;
638 		e->loc->argc = i - 1;
639 		getopts_reset(1);
640 
641 		old_xflag = Flag(FXTRACE);
642 		Flag(FXTRACE) = tp->flag & TRACE ? TRUE : FALSE;
643 
644 		old_inuse = tp->flag & FINUSE;
645 		tp->flag |= FINUSE;
646 
647 		e->type = E_FUNC;
648 		i = ksh_sigsetjmp(e->jbuf, 0);
649 		if (i == 0) {
650 			/* seems odd to pass XERROK here, but at&t ksh does */
651 			exstat = execute(tp->val.t, flags & XERROK);
652 			i = LRETURN;
653 		}
654 		kshname = old_kshname;
655 		Flag(FXTRACE) = old_xflag;
656 		tp->flag = (tp->flag & ~FINUSE) | old_inuse;
657 		/* Were we deleted while executing?  If so, free the execution
658 		 * tree.  todo: Unfortunately, the table entry is never re-used
659 		 * until the lookup table is expanded.
660 		 */
661 		if ((tp->flag & (FDELETE|FINUSE)) == FDELETE) {
662 			if (tp->flag & ALLOC) {
663 				tp->flag &= ~ALLOC;
664 				tfree(tp->val.t, tp->areap);
665 			}
666 			tp->flag = 0;
667 		}
668 		switch (i) {
669 		  case LRETURN:
670 		  case LERROR:
671 			rv = exstat;
672 			break;
673 		  case LINTR:
674 		  case LEXIT:
675 		  case LLEAVE:
676 		  case LSHELL:
677 			quitenv();
678 			unwind(i);
679 			/*NOTREACHED*/
680 		  default:
681 			quitenv();
682 			internal_errorf(1, "CFUNC %d", i);
683 		}
684 		break;
685 	  }
686 
687 	  case CEXEC:		/* executable command */
688 	  case CTALIAS:		/* tracked alias */
689 		if (!(tp->flag&ISSET)) {
690 			/* errno_ will be set if the named command was found
691 			 * but could not be executed (permissions, no execute
692 			 * bit, directory, etc).  Print out a (hopefully)
693 			 * useful error message and set the exit status to 126.
694 			 */
695 			if (tp->u2.errno_) {
696 				warningf(TRUE, "%s: cannot execute - %s", cp,
697 					strerror(tp->u2.errno_));
698 				rv = 126;	/* POSIX */
699 			} else {
700 				warningf(TRUE, "%s: not found", cp);
701 				rv = 127;
702 			}
703 			break;
704 		}
705 
706 		/* set $_ to program's full path */
707 		setstr(typeset("_", LOCAL|EXPORT, 0, 0, 0), tp->val.s);
708 
709 		if (flags&XEXEC) {
710 			j_exit();
711 			if (!(flags&XBGND) || Flag(FMONITOR)) {
712 				setexecsig(&sigtraps[SIGINT], SS_RESTORE_ORIG);
713 				setexecsig(&sigtraps[SIGQUIT], SS_RESTORE_ORIG);
714 			}
715 		}
716 
717 		/* to fork we set up a TEXEC node and call execute */
718 		texec.type = TEXEC;
719 		texec.left = t;	/* for tprint */
720 		texec.str = tp->val.s;
721 		texec.args = ap;
722 		rv = exchild(&texec, flags, -1);
723 		break;
724 	}
725   Leave:
726 	if (flags & XEXEC) {
727 		exstat = rv;
728 		unwind(LLEAVE);
729 	}
730 	return rv;
731 }
732 
733 static void
734 scriptexec(tp, ap)
735 	register struct op *tp;
736 	register char **ap;
737 {
738 	char *shell;
739 
740 	shell = str_val(global(EXECSHELL_STR));
741 	if (shell && *shell)
742 		shell = search(shell, path, X_OK, (int *) 0);
743 	if (!shell || !*shell)
744 		shell = EXECSHELL;
745 
746 	*tp->args-- = tp->str;
747 #ifdef	SHARPBANG
748 	{
749 		char buf[LINE];
750 		register char *cp;
751 		register int fd, n;
752 
753 		buf[0] = '\0';
754 		if ((fd = open(tp->str, O_RDONLY)) >= 0) {
755 			if ((n = read(fd, buf, LINE - 1)) > 0)
756 				buf[n] = '\0';
757 			(void) close(fd);
758 		}
759 		if ((buf[0] == '#' && buf[1] == '!' && (cp = &buf[2]))
760 # ifdef OS2
761 		    || (strncmp(buf, "extproc", 7) == 0 && isspace(buf[7])
762 			&& (cp = &buf[7]))
763 # endif /* OS2 */
764 		    )
765 		{
766 			while (*cp && (*cp == ' ' || *cp == '\t'))
767 				cp++;
768 			if (*cp && *cp != '\n') {
769 				char *a0 = cp, *a1 = (char *) 0;
770 # ifdef OS2
771 				char *a2 = cp;
772 # endif /* OS2 */
773 
774 				while (*cp && *cp != '\n' && *cp != ' '
775 				       && *cp != '\t')
776 				{
777 # ifdef OS2
778 			/* Allow shell search without prepended path
779 			 * if shell with / in pathname cannot be found.
780 			 * Use / explicitly so \ can be used if explicit
781 			 * needs to be forced.
782 			 */
783 					if (*cp == '/')
784 						a2 = cp + 1;
785 # endif /* OS2 */
786 					cp++;
787 				}
788 				if (*cp && *cp != '\n') {
789 					*cp++ = '\0';
790 					while (*cp
791 					       && (*cp == ' ' || *cp == '\t'))
792 						cp++;
793 					if (*cp && *cp != '\n') {
794 						a1 = cp;
795 						/* all one argument */
796 						while (*cp && *cp != '\n')
797 							cp++;
798 					}
799 				}
800 				if (*cp == '\n') {
801 					*cp = '\0';
802 					if (a1)
803 						*tp->args-- = a1;
804 # ifdef OS2
805 					if (a0 != a2 && search_access(a0, X_OK, (int *) 0))
806 						a0 = a2;
807 # endif /* OS2 */
808 					shell = a0;
809 				}
810 			}
811 # ifdef OS2
812 		} else {
813 		        /* Use ksh documented shell default if present
814 			 * else use OS2_SHELL which is assumed to need
815 			 * the /c option and '\' as dir separater.
816 			 */
817 		         char *p = shell;
818 
819 			 shell = str_val(global("EXECSHELL"));
820 			 if (shell && *shell)
821 				 shell = search(shell, path, X_OK, (int *) 0);
822 			 if (!shell || !*shell) {
823 				 shell = p;
824 				 *tp->args-- = "/c";
825 				 for (p = tp->str; *p; p++)
826 					 if (*p == '/')
827 						 *p = '\\';
828 			 }
829 # endif /* OS2 */
830 		}
831 	}
832 #endif	/* SHARPBANG */
833 	*tp->args = shell;
834 
835 	ksh_execve(tp->args[0], tp->args, ap);
836 
837 	/* report both the program that was run and the bogus shell */
838 	errorf("%s: %s: %s", tp->str, shell, strerror(errno));
839 }
840 
841 int
842 shcomexec(wp)
843 	register char **wp;
844 {
845 	register struct tbl *tp;
846 
847 	tp = tsearch(&builtins, *wp, hash(*wp));
848 	if (tp == NULL)
849 		internal_errorf(1, "shcomexec: %s", *wp);
850 	return call_builtin(tp, wp);
851 }
852 
853 /*
854  * Search function tables for a function.  If create set, a table entry
855  * is created if none is found.
856  */
857 struct tbl *
858 findfunc(name, h, create)
859 	const char *name;
860 	unsigned int	h;
861 	int	create;
862 {
863 	struct block *l;
864 	struct tbl *tp = (struct tbl *) 0;
865 
866 	for (l = e->loc; l; l = l->next) {
867 		tp = tsearch(&l->funs, name, h);
868 		if (tp)
869 			break;
870 		if (!l->next && create) {
871 			tp = tenter(&l->funs, name, h);
872 			tp->flag = DEFINED;
873 			tp->type = CFUNC;
874 			tp->val.t = (struct op *) 0;
875 			break;
876 		}
877 	}
878 	return tp;
879 }
880 
881 /*
882  * define function.  Returns 1 if function is being undefined (t == 0) and
883  * function did not exist, returns 0 otherwise.
884  */
885 int
886 define(name, t)
887 	const char *name;
888 	struct op *t;
889 {
890 	struct tbl *tp;
891 	int was_set = 0;
892 
893 	while (1) {
894 		tp = findfunc(name, hash(name), TRUE);
895 
896 		if (tp->flag & ISSET)
897 			was_set = 1;
898 		/* If this function is currently being executed, we zap this
899 		 * table entry so findfunc() won't see it
900 		 */
901 		if (tp->flag & FINUSE) {
902 			tp->name[0] = '\0';
903 			tp->flag &= ~DEFINED; /* ensure it won't be found */
904 			tp->flag |= FDELETE;
905 		} else
906 			break;
907 	}
908 
909 	if (tp->flag & ALLOC) {
910 		tp->flag &= ~(ISSET|ALLOC);
911 		tfree(tp->val.t, tp->areap);
912 	}
913 
914 	if (t == NULL) {		/* undefine */
915 		tdelete(tp);
916 		return was_set ? 0 : 1;
917 	}
918 
919 	tp->val.t = tcopy(t->left, tp->areap);
920 	tp->flag |= (ISSET|ALLOC);
921 	if (t->u.ksh_func)
922 	    tp->flag |= FKSH;
923 
924 	return 0;
925 }
926 
927 /*
928  * add builtin
929  */
930 void
931 builtin(name, func)
932 	const char *name;
933 	int (*func) ARGS((char **));
934 {
935 	register struct tbl *tp;
936 	Tflag flag;
937 
938 	/* see if any flags should be set for this builtin */
939 	for (flag = 0; ; name++) {
940 		if (*name == '=')	/* command does variable assignment */
941 			flag |= KEEPASN;
942 		else if (*name == '*')	/* POSIX special builtin */
943 			flag |= SPEC_BI;
944 		else if (*name == '+')	/* POSIX regular builtin */
945 			flag |= REG_BI;
946 		else
947 			break;
948 	}
949 
950 	tp = tenter(&builtins, name, hash(name));
951 	tp->flag = DEFINED | flag;
952 	tp->type = CSHELL;
953 	tp->val.f = func;
954 }
955 
956 /*
957  * find command
958  * either function, hashed command, or built-in (in that order)
959  */
960 struct tbl *
961 findcom(name, flags)
962 	const char *name;
963 	int	flags;		/* FC_* */
964 {
965 	static struct tbl temp;
966 	unsigned int h = hash(name);
967 	struct tbl *tp = NULL, *tbi;
968 	int insert = Flag(FTRACKALL);	/* insert if not found */
969 	char *fpath;			/* for function autoloading */
970 	char *npath;
971 
972 	if (ksh_strchr_dirsep(name) != NULL) {
973 		insert = 0;
974 		/* prevent FPATH search below */
975 		flags &= ~FC_FUNC;
976 		goto Search;
977 	}
978 	tbi = (flags & FC_BI) ? tsearch(&builtins, name, h) : NULL;
979 	/* POSIX says special builtins first, then functions, then
980 	 * POSIX regular builtins, then search path...
981 	 */
982 	if ((flags & FC_SPECBI) && tbi && (tbi->flag & SPEC_BI))
983 		tp = tbi;
984 	if (!tp && (flags & FC_FUNC)) {
985 		tp = findfunc(name, h, FALSE);
986 		if (tp && !(tp->flag & ISSET)) {
987 			if ((fpath = str_val(global("FPATH"))) == null) {
988 				tp->u.fpath = (char *) 0;
989 				tp->u2.errno_ = 0;
990 			} else
991 				tp->u.fpath = search(name, fpath, R_OK,
992 					&tp->u2.errno_);
993 		}
994 	}
995 	if (!tp && (flags & FC_REGBI) && tbi && (tbi->flag & REG_BI))
996 		tp = tbi;
997 	/* todo: posix says non-special/non-regular builtins must
998 	 * be triggered by some user-controllable means like a
999 	 * special directory in PATH.  Requires modifications to
1000 	 * the search() function.  Tracked aliases should be
1001 	 * modified to allow tracking of builtin commands.
1002 	 * This should be under control of the FPOSIX flag.
1003 	 * If this is changed, also change c_whence...
1004 	 */
1005 	if (!tp && (flags & FC_UNREGBI) && tbi)
1006 		tp = tbi;
1007 	if (!tp && (flags & FC_PATH) && !(flags & FC_DEFPATH)) {
1008 		tp = tsearch(&taliases, name, h);
1009 		if (tp && (tp->flag & ISSET) && eaccess(tp->val.s, X_OK) != 0) {
1010 			if (tp->flag & ALLOC) {
1011 				tp->flag &= ~ALLOC;
1012 				afree(tp->val.s, APERM);
1013 			}
1014 			tp->flag &= ~ISSET;
1015 		}
1016 	}
1017 
1018   Search:
1019 	if ((!tp || (tp->type == CTALIAS && !(tp->flag&ISSET)))
1020 	    && (flags & FC_PATH))
1021 	{
1022 		if (!tp) {
1023 			if (insert && !(flags & FC_DEFPATH)) {
1024 				tp = tenter(&taliases, name, h);
1025 				tp->type = CTALIAS;
1026 			} else {
1027 				tp = &temp;
1028 				tp->type = CEXEC;
1029 			}
1030 			tp->flag = DEFINED;	/* make ~ISSET */
1031 		}
1032 		npath = search(name, flags & FC_DEFPATH ? def_path : path,
1033 				X_OK, &tp->u2.errno_);
1034 		if (npath) {
1035 			tp->val.s = tp == &temp ? npath : str_save(npath, APERM);
1036 			tp->flag |= ISSET|ALLOC;
1037 		} else if ((flags & FC_FUNC)
1038 			   && (fpath = str_val(global("FPATH"))) != null
1039 			   && (npath = search(name, fpath, R_OK,
1040 					      &tp->u2.errno_)) != (char *) 0)
1041 		{
1042 			/* An undocumented feature of at&t ksh is that it
1043 			 * searches FPATH if a command is not found, even
1044 			 * if the command hasn't been set up as an autoloaded
1045 			 * function (ie, no typeset -uf).
1046 			 */
1047 			tp = &temp;
1048 			tp->type = CFUNC;
1049 			tp->flag = DEFINED; /* make ~ISSET */
1050 			tp->u.fpath = npath;
1051 		}
1052 	}
1053 	return tp;
1054 }
1055 
1056 /*
1057  * flush executable commands with relative paths
1058  */
1059 void
1060 flushcom(all)
1061 	int all;		/* just relative or all */
1062 {
1063 	struct tbl *tp;
1064 	struct tstate ts;
1065 
1066 	for (twalk(&ts, &taliases); (tp = tnext(&ts)) != NULL; )
1067 		if ((tp->flag&ISSET) && (all || !ISDIRSEP(tp->val.s[0]))) {
1068 			if (tp->flag&ALLOC) {
1069 				tp->flag &= ~(ALLOC|ISSET);
1070 				afree(tp->val.s, APERM);
1071 			}
1072 			tp->flag = ~ISSET;
1073 		}
1074 }
1075 
1076 /* Check if path is something we want to find.  Returns -1 for failure. */
1077 int
1078 search_access(path, mode, errnop)
1079 	const char *path;
1080 	int mode;
1081 	int *errnop;		/* set if candidate found, but not suitable */
1082 {
1083 #ifndef OS2
1084 	int ret, err = 0;
1085 	struct stat statb;
1086 
1087 	if (stat(path, &statb) < 0)
1088 		return -1;
1089 	ret = eaccess(path, mode);
1090 	if (ret < 0)
1091 		err = errno; /* File exists, but we can't access it */
1092 	else if (mode == X_OK && (!S_ISREG(statb.st_mode)
1093 		   /* This 'cause access() says root can execute everything */
1094 		   || !(statb.st_mode & (S_IXUSR|S_IXGRP|S_IXOTH))))
1095 	{
1096 		ret = -1;
1097 		err = S_ISDIR(statb.st_mode) ? EISDIR : EACCES;
1098 	}
1099 	if (err && errnop)
1100 		*errnop = err;
1101 	return ret;
1102 #else /* !OS2 */
1103 	/*
1104 	 * NOTE: ASSUMES path can be modified and has enough room at the
1105 	 *       end of the string for a suffix (ie, 4 extra characters).
1106 	 *	 Certain code knows this (eg, eval.c(globit()),
1107 	 *	 exec.c(search())).
1108 	 */
1109 	static char *xsuffixes[] = { ".ksh", ".exe", ".", ".sh", ".cmd",
1110 				     ".com", ".bat", (char *) 0
1111 				   };
1112 	static char *rsuffixes[] = { ".ksh", ".", ".sh", ".cmd", ".bat",
1113 				      (char *) 0
1114 				   };
1115 	int i;
1116 	char *mpath = (char *) path;
1117 	char *tp = mpath + strlen(mpath);
1118 	char *p;
1119 	char **sfx;
1120 
1121 	/* If a suffix has been specified, check if it is one of the
1122 	 * suffixes that indicate the file is executable - if so, change
1123 	 * the access test to R_OK...
1124 	 * This code assumes OS/2 files can have only one suffix...
1125 	 */
1126 	if ((p = strrchr((p = ksh_strrchr_dirsep(mpath)) ? p : mpath, '.'))) {
1127 		if (mode == X_OK)
1128 			mode = R_OK;
1129 		return search_access1(mpath, mode, errnop);
1130 	}
1131 	/* Try appending the various suffixes.  Different suffixes for
1132 	 * read and execute 'cause we don't want to read an executable...
1133 	 */
1134 	sfx = mode == R_OK ? rsuffixes : xsuffixes;
1135 	for (i = 0; sfx[i]; i++) {
1136 		strcpy(tp, p = sfx[i]);
1137 		if (search_access1(mpath, R_OK, errnop) == 0)
1138 			return 0;
1139 		*tp = '\0';
1140 	}
1141 	return -1;
1142 #endif /* !OS2 */
1143 }
1144 
1145 #ifdef OS2
1146 static int
1147 search_access1(path, mode, errnop)
1148 	const char *path;
1149 	int mode;
1150 	int *errnop;		/* set if candidate found, but not suitable */
1151 {
1152 	int ret, err = 0;
1153 	struct stat statb;
1154 
1155 	if (stat(path, &statb) < 0)
1156 		return -1;
1157 	ret = eaccess(path, mode);
1158 	if (ret < 0)
1159 		err = errno; /* File exists, but we can't access it */
1160 	else if (!S_ISREG(statb.st_mode)) {
1161 		ret = -1;
1162 		err = S_ISDIR(statb.st_mode) ? EISDIR : EACCES;
1163 	}
1164 	if (err && errnop)
1165 		*errnop = err;
1166 	return ret;
1167 }
1168 #endif /* OS2 */
1169 
1170 /*
1171  * search for command with PATH
1172  */
1173 char *
1174 search(name, path, mode, errnop)
1175 	const char *name;
1176 	const char *path;
1177 	int mode;		/* R_OK or X_OK */
1178 	int *errnop;		/* set if candidate found, but not suitable */
1179 {
1180 	const char *sp, *p;
1181 	char *xp;
1182 	XString xs;
1183 	int namelen;
1184 
1185 	if (errnop)
1186 		*errnop = 0;
1187 #ifdef OS2
1188 	/* Xinit() allocates 8 additional bytes, so appended suffixes won't
1189 	 * overflow the memory.
1190 	 */
1191 	namelen = strlen(name) + 1;
1192 	Xinit(xs, xp, namelen, ATEMP);
1193 	memcpy(Xstring(xs, xp), name, namelen);
1194 
1195  	if (ksh_strchr_dirsep(name)) {
1196 		if (search_access(Xstring(xs, xp), mode, errnop) >= 0)
1197 			return Xstring(xs, xp); /* not Xclose() - see above */
1198 		Xfree(xs, xp);
1199 		return NULL;
1200 	}
1201 
1202 	/* Look in current context always. (os2 style) */
1203 	if (search_access(Xstring(xs, xp), mode, errnop) == 0)
1204 		return Xstring(xs, xp); /* not Xclose() - xp may be wrong */
1205 #else /* OS2 */
1206 	if (ksh_strchr_dirsep(name)) {
1207 		if (search_access(name, mode, errnop) == 0)
1208 			return (char *) name;
1209 		return NULL;
1210 	}
1211 
1212 	namelen = strlen(name) + 1;
1213 	Xinit(xs, xp, 128, ATEMP);
1214 #endif /* OS2 */
1215 
1216 	sp = path;
1217 	while (sp != NULL) {
1218 		xp = Xstring(xs, xp);
1219 		if (!(p = strchr(sp, PATHSEP)))
1220 			p = sp + strlen(sp);
1221 		if (p != sp) {
1222 			XcheckN(xs, xp, p - sp);
1223 			memcpy(xp, sp, p - sp);
1224 			xp += p - sp;
1225 			*xp++ = DIRSEP;
1226 		}
1227 		sp = p;
1228 		XcheckN(xs, xp, namelen);
1229 		memcpy(xp, name, namelen);
1230  		if (search_access(Xstring(xs, xp), mode, errnop) == 0)
1231 #ifdef OS2
1232  			return Xstring(xs, xp); /* Not Xclose() - see above */
1233 #else /* OS2 */
1234 			return Xclose(xs, xp + namelen);
1235 #endif /* OS2 */
1236 		if (*sp++ == '\0')
1237 			sp = NULL;
1238 	}
1239 	Xfree(xs, xp);
1240 	return NULL;
1241 }
1242 
1243 static int
1244 call_builtin(tp, wp)
1245 	struct tbl *tp;
1246 	char **wp;
1247 {
1248 	int rv;
1249 
1250 	builtin_argv0 = wp[0];
1251 	builtin_flag = tp->flag;
1252 	shf_reopen(1, SHF_WR, shl_stdout);
1253 	shl_stdout_ok = 1;
1254 	ksh_getopt_reset(&builtin_opt, GF_ERROR);
1255 	rv = (*tp->val.f)(wp);
1256 	shf_flush(shl_stdout);
1257 	shl_stdout_ok = 0;
1258 	builtin_flag = 0;
1259 	builtin_argv0 = (char *) 0;
1260 	return rv;
1261 }
1262 
1263 /*
1264  * set up redirection, saving old fd's in e->savefd
1265  */
1266 static int
1267 iosetup(iop, tp)
1268 	register struct ioword *iop;
1269 	struct tbl *tp;
1270 {
1271 	register int u = -1;
1272 	char *cp = iop->name;
1273 	int iotype = iop->flag & IOTYPE;
1274 	int do_open = 1, do_close = 0, UNINITIALIZED(flags);
1275 	struct ioword iotmp;
1276 	struct stat statb;
1277 
1278 	if (iotype != IOHERE)
1279 		cp = evalonestr(cp, DOTILDE|(Flag(FTALKING) ? DOGLOB : 0));
1280 
1281 	/* Used for tracing and error messages to print expanded cp */
1282 	iotmp = *iop;
1283 	iotmp.name = (iotype == IOHERE) ? (char *) 0 : cp;
1284 	iotmp.flag |= IONAMEXP;
1285 
1286 	if (Flag(FXTRACE))
1287 		shellf("%s%s\n",
1288 			PS4_SUBSTITUTE(str_val(global("PS4"))),
1289 			snptreef((char *) 0, 32, "%R", &iotmp));
1290 
1291 	switch (iotype) {
1292 	  case IOREAD:
1293 		flags = O_RDONLY;
1294 		break;
1295 
1296 	  case IOCAT:
1297 		flags = O_WRONLY | O_APPEND | O_CREAT;
1298 		break;
1299 
1300 	  case IOWRITE:
1301 		flags = O_WRONLY | O_CREAT | O_TRUNC;
1302 		if (Flag(FNOCLOBBER) && !(iop->flag & IOCLOB)
1303 		    && (stat(cp, &statb) < 0 || S_ISREG(statb.st_mode)))
1304 			flags |= O_EXCL;
1305 		break;
1306 
1307 	  case IORDWR:
1308 		flags = O_RDWR | O_CREAT;
1309 		break;
1310 
1311 	  case IOHERE:
1312 		do_open = 0;
1313 		/* herein() returns -2 if error has been printed */
1314 		u = herein(cp, iop->flag & IOEVAL);
1315 		/* cp may have wrong name */
1316 		break;
1317 
1318 	  case IODUP:
1319 	  {
1320 		const char *emsg;
1321 
1322 		do_open = 0;
1323 		if (*cp == '-' && !cp[1]) {
1324 			u = 1009;	 /* prevent error return below */
1325 			do_close = 1;
1326 		} else if ((u = check_fd(cp,
1327 				X_OK | ((iop->flag & IORDUP) ? R_OK : W_OK),
1328 				&emsg)) < 0)
1329 		{
1330 			warningf(TRUE, "%s: %s",
1331 				snptreef((char *) 0, 32, "%R", &iotmp), emsg);
1332 			return -1;
1333 		}
1334 		break;
1335 	  }
1336 	}
1337 	if (do_open) {
1338 		if (Flag(FRESTRICTED) && (flags & O_CREAT)) {
1339 			warningf(TRUE, "%s: restricted", cp);
1340 			return -1;
1341 		}
1342 		u = open(cp, flags, 0666);
1343 #ifdef OS2
1344 		if (u < 0 && strcmp(cp, "/dev/null") == 0)
1345 			u = open("nul", flags, 0666);
1346 #endif /* OS2 */
1347 	}
1348 	if (u < 0) {
1349 		/* herein() may already have printed message */
1350 		if (u == -1)
1351 			warningf(TRUE, "cannot %s %s: %s",
1352 			       iotype == IODUP ? "dup"
1353 				: (iotype == IOREAD || iotype == IOHERE) ?
1354 				    "open" : "create", cp, strerror(errno));
1355 		return -1;
1356 	}
1357 	/* Do not save if it has already been redirected (i.e. "cat >x >y"). */
1358 	if (e->savefd[iop->unit] == 0)
1359 		/* c_exec() assumes e->savefd[fd] set for any redirections.
1360 		 * Ask savefd() not to close iop->unit - allows error messages
1361 		 * to be seen if iop->unit is 2; also means we can't lose
1362 		 * the fd (eg, both dup2 below and dup2 in restfd() failing).
1363 		 */
1364 		e->savefd[iop->unit] = savefd(iop->unit, 1);
1365 
1366 	if (do_close)
1367 		close(iop->unit);
1368 	else if (u != iop->unit) {
1369 		if (ksh_dup2(u, iop->unit, TRUE) < 0) {
1370 			warningf(TRUE,
1371 				"could not finish (dup) redirection %s: %s",
1372 				snptreef((char *) 0, 32, "%R", &iotmp),
1373 				strerror(errno));
1374 			if (iotype != IODUP)
1375 				close(u);
1376 			return -1;
1377 		}
1378 		if (iotype != IODUP)
1379 			close(u);
1380 #ifdef KSH
1381 		/* Touching any co-process fd in an empty exec
1382 		 * causes the shell to close its copies
1383 		 */
1384 		else if (tp && tp->type == CSHELL && tp->val.f == c_exec) {
1385 			if (iop->flag & IORDUP)	/* possible exec <&p */
1386 				coproc_read_close(u);
1387 			else			/* possible exec >&p */
1388 				coproc_write_close(u);
1389 		}
1390 #endif /* KSH */
1391 	}
1392 	if (u == 2) /* Clear any write errors */
1393 		shf_reopen(2, SHF_WR, shl_out);
1394 	return 0;
1395 }
1396 
1397 /*
1398  * open here document temp file.
1399  * if unquoted here, expand here temp file into second temp file.
1400  */
1401 static int
1402 herein(hname, sub)
1403 	char *hname;
1404 	int sub;
1405 {
1406 	int fd;
1407 
1408 	/* ksh -c 'cat << EOF' can cause this... */
1409 	if (hname == (char *) 0) {
1410 		warningf(TRUE, "here document missing");
1411 		return -2; /* special to iosetup(): don't print error */
1412 	}
1413 	if (sub) {
1414 		char *cp;
1415 		struct source *s, *volatile osource = source;
1416 		struct temp *h;
1417 		struct shf *volatile shf;
1418 		int i;
1419 
1420 		/* must be before newenv() 'cause shf uses ATEMP */
1421 		shf = shf_open(hname, O_RDONLY, 0, SHF_MAPHI|SHF_CLEXEC);
1422 		if (shf == NULL)
1423 			return -1;
1424 		newenv(E_ERRH);
1425 		i = ksh_sigsetjmp(e->jbuf, 0);
1426 		if (i) {
1427 			if (shf)
1428 				shf_close(shf);
1429 			source = osource;
1430 			quitenv(); /* after shf_close() due to alloc */
1431 			return -2; /* special to iosetup(): don't print error */
1432 		}
1433 		/* set up yylex input from here file */
1434 		s = pushs(SFILE, ATEMP);
1435 		s->u.shf = shf;
1436 		source = s;
1437 		if (yylex(ONEWORD) != LWORD)
1438 			internal_errorf(1, "herein: yylex");
1439 		shf_close(shf);
1440 		shf = (struct shf *) 0;
1441 		cp = evalstr(yylval.cp, 0);
1442 
1443 		/* write expanded input to another temp file */
1444 		h = maketemp(ATEMP);
1445 		h->next = e->temps; e->temps = h;
1446 		if (!(shf = h->shf) || (fd = open(h->name, O_RDONLY, 0)) < 0)
1447 			/* shf closeed by error handler */
1448 			errorf("%s: %s", h->name, strerror(errno));
1449 		shf_puts(cp, shf);
1450 		if (shf_close(shf) == EOF) {
1451 			close(fd);
1452 			shf = (struct shf *) 0;
1453 			errorf("error writing %s: %s", h->name,
1454 				strerror(errno));
1455 		}
1456 		shf = (struct shf *) 0;
1457 
1458 		quitenv();
1459 	} else {
1460 		fd = open(hname, O_RDONLY, 0);
1461 		if (fd < 0)
1462 			return -1;
1463 	}
1464 
1465 	return fd;
1466 }
1467 
1468 #ifdef KSH
1469 /*
1470  *	ksh special - the select command processing section
1471  *	print the args in column form - assuming that we can
1472  */
1473 static char *
1474 do_selectargs(ap, print_menu)
1475 	register char **ap;
1476 	bool_t print_menu;
1477 {
1478 	static const char *const read_args[] = {
1479 					"read", "-r", "REPLY", (char *) 0
1480 				    };
1481 	char *s;
1482 	int i, argct;
1483 
1484 	for (argct = 0; ap[argct]; argct++)
1485 		;
1486 	while (1) {
1487 		/* Menu is printed if
1488 		 *	- this is the first time around the select loop
1489 		 *	- the user enters a blank line
1490 		 *	- the REPLY parameter is empty
1491 		 */
1492 		if (print_menu || !*str_val(global("REPLY")))
1493 			pr_menu(ap);
1494 		shellf("%s", str_val(global("PS3")));
1495 		if (call_builtin(findcom("read", FC_BI), (char **) read_args))
1496 			return (char *) 0;
1497 		s = str_val(global("REPLY"));
1498 		if (*s) {
1499 			i = atoi(s);
1500 			return (i >= 1 && i <= argct) ? ap[i - 1] : null;
1501 		}
1502 		print_menu = 1;
1503 	}
1504 }
1505 
1506 struct select_menu_info {
1507 	char	*const *args;
1508 	int	arg_width;
1509 	int	num_width;
1510 } info;
1511 
1512 static char *select_fmt_entry ARGS((void *arg, int i, char *buf, int buflen));
1513 
1514 /* format a single select menu item */
1515 static char *
1516 select_fmt_entry(arg, i, buf, buflen)
1517 	void *arg;
1518 	int i;
1519 	char *buf;
1520 	int buflen;
1521 {
1522 	struct select_menu_info *smi = (struct select_menu_info *) arg;
1523 
1524 	shf_snprintf(buf, buflen, "%*d) %s",
1525 		smi->num_width, i + 1, smi->args[i]);
1526 	return buf;
1527 }
1528 
1529 /*
1530  *	print a select style menu
1531  */
1532 int
1533 pr_menu(ap)
1534 	char *const *ap;
1535 {
1536 	struct select_menu_info smi;
1537 	char *const *pp;
1538 	int nwidth, dwidth;
1539 	int i, n;
1540 
1541 	/* Width/column calculations were done once and saved, but this
1542 	 * means select can't be used recursively so we re-calculate each
1543 	 * time (could save in a structure that is returned, but its probably
1544 	 * not worth the bother).
1545 	 */
1546 
1547 	/*
1548 	 * get dimensions of the list
1549 	 */
1550 	for (n = 0, nwidth = 0, pp = ap; *pp; n++, pp++) {
1551 		i = strlen(*pp);
1552 		nwidth = (i > nwidth) ? i : nwidth;
1553 	}
1554 	/*
1555 	 * we will print an index of the form
1556 	 *	%d)
1557 	 * in front of each entry
1558 	 * get the max width of this
1559 	 */
1560 	for (i = n, dwidth = 1; i >= 10; i /= 10)
1561 		dwidth++;
1562 
1563 	smi.args = ap;
1564 	smi.arg_width = nwidth;
1565 	smi.num_width = dwidth;
1566 	print_columns(shl_out, n, select_fmt_entry, (void *) &smi,
1567 		dwidth + nwidth + 2);
1568 
1569 	return n;
1570 }
1571 #endif /* KSH */
1572 #ifdef KSH
1573 
1574 /*
1575  *	[[ ... ]] evaluation routines
1576  */
1577 
1578 extern const char *const dbtest_tokens[];
1579 extern const char db_close[];
1580 
1581 /* Test if the current token is a whatever.  Accepts the current token if
1582  * it is.  Returns 0 if it is not, non-zero if it is (in the case of
1583  * TM_UNOP and TM_BINOP, the returned value is a Test_op).
1584  */
1585 static int
1586 dbteste_isa(te, meta)
1587 	Test_env *te;
1588 	Test_meta meta;
1589 {
1590 	int ret = 0;
1591 	int uqword;
1592 	char *p;
1593 
1594 	if (!*te->pos.wp)
1595 		return meta == TM_END;
1596 
1597 	/* unquoted word? */
1598 	for (p = *te->pos.wp; *p == CHAR; p += 2)
1599 		;
1600 	uqword = *p == EOS;
1601 
1602 	if (meta == TM_UNOP || meta == TM_BINOP) {
1603 		if (uqword) {
1604 			char buf[8];	/* longer than the longest operator */
1605 			char *q = buf;
1606 			for (p = *te->pos.wp; *p == CHAR
1607 					      && q < &buf[sizeof(buf) - 1];
1608 					      p += 2)
1609 				*q++ = p[1];
1610 			*q = '\0';
1611 			ret = (int) test_isop(te, meta, buf);
1612 		}
1613 	} else if (meta == TM_END)
1614 		ret = 0;
1615 	else
1616 		ret = uqword
1617 			&& strcmp(*te->pos.wp, dbtest_tokens[(int) meta]) == 0;
1618 
1619 	/* Accept the token? */
1620 	if (ret)
1621 		te->pos.wp++;
1622 
1623 	return ret;
1624 }
1625 
1626 static const char *
1627 dbteste_getopnd(te, op, do_eval)
1628 	Test_env *te;
1629 	Test_op op;
1630 	int do_eval;
1631 {
1632 	char *s = *te->pos.wp;
1633 
1634 	if (!s)
1635 		return (char *) 0;
1636 
1637 	te->pos.wp++;
1638 
1639 	if (!do_eval)
1640 		return null;
1641 
1642 	if (op == TO_STEQL || op == TO_STNEQ)
1643 		s = evalstr(s, DOTILDE | DOPAT);
1644 	else
1645 		s = evalstr(s, DOTILDE);
1646 
1647 	return s;
1648 }
1649 
1650 static int
1651 dbteste_eval(te, op, opnd1, opnd2, do_eval)
1652 	Test_env *te;
1653 	Test_op op;
1654 	const char *opnd1;
1655 	const char *opnd2;
1656 	int do_eval;
1657 {
1658 	return test_eval(te, op, opnd1, opnd2, do_eval);
1659 }
1660 
1661 static void
1662 dbteste_error(te, offset, msg)
1663 	Test_env *te;
1664 	int offset;
1665 	const char *msg;
1666 {
1667 	te->flags |= TEF_ERROR;
1668 	internal_errorf(0, "dbteste_error: %s (offset %d)", msg, offset);
1669 }
1670 #endif /* KSH */
1671