xref: /plan9/sys/src/ape/cmd/pdksh/exec.c (revision 7dd7cddf99dd7472612f1413b4da293630e6b1bc)
1 /*
2  * execute command tree
3  */
4 
5 #include "sh.h"
6 #include "c_test.h"
7 #include <ctype.h>
8 #include "ksh_stat.h"
9 
10 /* Does ps4 get parameter substitutions done? */
11 #ifdef KSH
12 # define PS4_SUBSTITUTE(s)	substitute((s), 0)
13 #else
14 # define PS4_SUBSTITUTE(s)	(s)
15 #endif /* KSH */
16 
17 static int	comexec	 ARGS((struct op *t, struct tbl *volatile tp, char **ap,
18 			      int volatile flags));
19 static void	scriptexec ARGS((struct op *tp, char **ap));
20 static int	call_builtin ARGS((struct tbl *tp, char **wp));
21 static int	iosetup ARGS((struct ioword *iop, struct tbl *tp));
22 static int	herein ARGS((const char *content, int sub));
23 #ifdef KSH
24 static char 	*do_selectargs ARGS((char **ap, bool_t print_menu));
25 #endif /* KSH */
26 #ifdef KSH
27 static int	dbteste_isa ARGS((Test_env *te, Test_meta meta));
28 static const char *dbteste_getopnd ARGS((Test_env *te, Test_op op,
29 					 int do_eval));
30 static int	dbteste_eval ARGS((Test_env *te, Test_op op, const char *opnd1,
31 				const char *opnd2, int do_eval));
32 static void	dbteste_error ARGS((Test_env *te, int offset, const char *msg));
33 #endif /* KSH */
34 #ifdef OS2
35 static int	search_access1 ARGS((const char *path, int mode, int *errnop));
36 #endif /* OS2 */
37 
38 
39 /*
40  * handle systems that don't have F_SETFD
41  */
42 #ifndef F_SETFD
43 # ifndef MAXFD
44 #   define  MAXFD 64
45 # endif
46 /* a bit field would be smaller, but this will work */
47 static char clexec_tab[MAXFD+1];
48 #endif
49 
50 /*
51  * we now use this function always.
52  */
53 int
fd_clexec(fd)54 fd_clexec(fd)
55     int fd;
56 {
57 #ifndef F_SETFD
58 	if (fd >= 0 && fd < sizeof(clexec_tab)) {
59 		clexec_tab[fd] = 1;
60 		return 0;
61 	}
62 	return -1;
63 #else
64 	return fcntl(fd, F_SETFD, 1);
65 #endif
66 }
67 
68 
69 /*
70  * execute command tree
71  */
72 int
execute(t,flags)73 execute(t, flags)
74 	struct op * volatile t;
75 	volatile int flags;	/* if XEXEC don't fork */
76 {
77 	int i;
78 	volatile int rv = 0;
79 	int pv[2];
80 	char ** volatile ap;
81 	char *s, *cp;
82 	struct ioword **iowp;
83 	struct tbl *tp = NULL;
84 
85 	if (t == NULL)
86 		return 0;
87 
88 	/* Is this the end of a pipeline?  If so, we want to evaluate the
89 	 * command arguments
90 	bool_t eval_done = FALSE;
91 	if ((flags&XFORK) && !(flags&XEXEC) && (flags&XPCLOSE)) {
92 		eval_done = TRUE;
93 		tp = eval_execute_args(t, &ap);
94 	}
95 	 */
96 	if ((flags&XFORK) && !(flags&XEXEC) && t->type != TPIPE)
97 		return exchild(t, flags & ~XTIME, -1); /* run in sub-process */
98 
99 	newenv(E_EXEC);
100 	if (trap)
101 		runtraps(0);
102 
103 	if (t->type == TCOM) {
104 		/* Clear subst_exstat before argument expansion.  Used by
105 		 * null commands (see comexec() and c_eval()) and by c_set().
106 		 */
107 		subst_exstat = 0;
108 
109 		current_lineno = t->lineno;	/* for $LINENO */
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 (flags & XTIME)
116 			/* Allow option parsing (bizarre, but POSIX) */
117 			timex_hook(t, &ap);
118 		if (Flag(FXTRACE) && ap[0]) {
119 			shf_fprintf(shl_out, "%s",
120 				PS4_SUBSTITUTE(str_val(global("PS4"))));
121 			for (i = 0; ap[i]; i++)
122 				shf_fprintf(shl_out, "%s%s", ap[i],
123 					ap[i + 1] ? space : newline);
124 			shf_flush(shl_out);
125 		}
126 		if (ap[0])
127 			tp = findcom(ap[0], FC_BI|FC_FUNC);
128 	}
129 	flags &= ~XTIME;
130 
131 	if (t->ioact != NULL || t->type == TPIPE || t->type == TCOPROC) {
132 		e->savefd = (short *) alloc(sizeofN(short, NUFILE), ATEMP);
133 		/* initialize to not redirected */
134 		memset(e->savefd, 0, sizeofN(short, NUFILE));
135 	}
136 
137 	/* do redirection, to be restored in quitenv() */
138 	if (t->ioact != NULL)
139 		for (iowp = t->ioact; *iowp != NULL; iowp++) {
140 			if (iosetup(*iowp, tp) < 0) {
141 				exstat = rv = 1;
142 				/* Redirection failures for special commands
143 				 * cause (non-interactive) shell to exit.
144 				 */
145 				if (tp && tp->type == CSHELL
146 				    && (tp->flag & SPEC_BI))
147 					errorf(null);
148 				/* Deal with FERREXIT, quitenv(), etc. */
149 				goto Break;
150 			}
151 		}
152 
153 	switch(t->type) {
154 	  case TCOM:
155 		rv = comexec(t, tp, ap, flags);
156 		break;
157 
158 	  case TPAREN:
159 		rv = execute(t->left, flags|XFORK);
160 		break;
161 
162 	  case TPIPE:
163 		flags |= XFORK;
164 		flags &= ~XEXEC;
165 		e->savefd[0] = savefd(0, 0);
166 		(void) ksh_dup2(e->savefd[0], 0, FALSE); /* stdin of first */
167 		e->savefd[1] = savefd(1, 0);
168 		while (t->type == TPIPE) {
169 			openpipe(pv);
170 			(void) ksh_dup2(pv[1], 1, FALSE); /* stdout of curr */
171 			/* Let exchild() close pv[0] in child
172 			 * (if this isn't done, commands like
173 			 *    (: ; cat /etc/termcap) | sleep 1
174 			 *  will hang forever).
175 			 */
176 			exchild(t->left, flags|XPIPEO|XCCLOSE, pv[0]);
177 			(void) ksh_dup2(pv[0], 0, FALSE); /* stdin of next */
178 			closepipe(pv);
179 			flags |= XPIPEI;
180 			t = t->right;
181 		}
182 		restfd(1, e->savefd[1]); /* stdout of last */
183 		e->savefd[1] = 0; /* no need to re-restore this */
184 		/* Let exchild() close 0 in parent, after fork, before wait */
185 		i = exchild(t, flags|XPCLOSE, 0);
186 		if (!(flags&XBGND) && !(flags&XXCOM))
187 			rv = i;
188 		break;
189 
190 	  case TLIST:
191 		while (t->type == TLIST) {
192 			execute(t->left, flags & XERROK);
193 			t = t->right;
194 		}
195 		rv = execute(t, flags & XERROK);
196 		break;
197 
198 #ifdef KSH
199 	  case TCOPROC:
200 	  {
201 # ifdef JOB_SIGS
202 		sigset_t	omask;
203 # endif /* JOB_SIGS */
204 
205 # ifdef JOB_SIGS
206 		/* Block sigchild as we are using things changed in the
207 		 * signal handler
208 		 */
209 		sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
210 		e->type = E_ERRH;
211 		i = ksh_sigsetjmp(e->jbuf, 0);
212 		if (i) {
213 			sigprocmask(SIG_SETMASK, &omask, (sigset_t *) 0);
214 			quitenv();
215 			unwind(i);
216 			/*NOTREACHED*/
217 		}
218 # endif /* JOB_SIGS */
219 		/* Already have a (live) co-process? */
220 		if (coproc.job && coproc.write >= 0)
221 			errorf("coprocess already exists");
222 
223 		/* Can we re-use the existing co-process pipe? */
224 		coproc_cleanup(TRUE);
225 
226 		/* do this before opening pipes, in case these fail */
227 		e->savefd[0] = savefd(0, 0);
228 		e->savefd[1] = savefd(1, 0);
229 
230 		openpipe(pv);
231 		ksh_dup2(pv[0], 0, FALSE);
232 		close(pv[0]);
233 		coproc.write = pv[1];
234 		coproc.job = (void *) 0;
235 
236 		if (coproc.readw >= 0)
237 			ksh_dup2(coproc.readw, 1, FALSE);
238 		else {
239 			openpipe(pv);
240 			coproc.read = pv[0];
241 			ksh_dup2(pv[1], 1, FALSE);
242 			coproc.readw = pv[1];	 /* closed before first read */
243 			coproc.njobs = 0;
244 			/* create new coprocess id */
245 			++coproc.id;
246 		}
247 # ifdef JOB_SIGS
248 		sigprocmask(SIG_SETMASK, &omask, (sigset_t *) 0);
249 		e->type = E_EXEC; /* no more need for error handler */
250 # endif /* JOB_SIGS */
251 
252 		/* exchild() closes coproc.* in child after fork,
253 		 * will also increment coproc.njobs when the
254 		 * job is actually created.
255 		 */
256 		flags &= ~XEXEC;
257 		exchild(t->left, flags|XBGND|XFORK|XCOPROC|XCCLOSE,
258 			coproc.readw);
259 		break;
260 	  }
261 #endif /* KSH */
262 
263 	  case TASYNC:
264 		/* XXX non-optimal, I think - "(foo &)", forks for (),
265 		 * forks again for async...  parent should optimize
266 		 * this to "foo &"...
267 		 */
268 		rv = execute(t->left, (flags&~XEXEC)|XBGND|XFORK);
269 		break;
270 
271 	  case TOR:
272 	  case TAND:
273 		rv = execute(t->left, XERROK);
274 		if (t->right != NULL && (rv == 0) == (t->type == TAND))
275 			rv = execute(t->right, flags & XERROK);
276 		else
277 			flags |= XERROK;
278 		break;
279 
280 	  case TBANG:
281 		rv = !execute(t->right, XERROK);
282 		break;
283 
284 #ifdef KSH
285 	  case TDBRACKET:
286 	    {
287 		Test_env te;
288 
289 		te.flags = TEF_DBRACKET;
290 		te.pos.wp = t->args;
291 		te.isa = dbteste_isa;
292 		te.getopnd = dbteste_getopnd;
293 		te.eval = dbteste_eval;
294 		te.error = dbteste_error;
295 
296 		rv = test_parse(&te);
297 		break;
298 	    }
299 #endif /* KSH */
300 
301 	  case TFOR:
302 #ifdef KSH
303 	  case TSELECT:
304 	    {
305 		volatile bool_t is_first = TRUE;
306 #endif /* KSH */
307 		ap = (t->vars != NULL) ?
308 			  eval(t->vars, DOBLANK|DOGLOB|DOTILDE)
309 			: e->loc->argv + 1;
310 		e->type = E_LOOP;
311 		while (1) {
312 			i = ksh_sigsetjmp(e->jbuf, 0);
313 			if (!i)
314 				break;
315 			if ((e->flags&EF_BRKCONT_PASS)
316 			    || (i != LBREAK && i != LCONTIN))
317 			{
318 				quitenv();
319 				unwind(i);
320 			} else if (i == LBREAK) {
321 				rv = 0;
322 				goto Break;
323 			}
324 		}
325 		rv = 0; /* in case of a continue */
326 		if (t->type == TFOR) {
327 			while (*ap != NULL) {
328 				setstr(global(t->str), *ap++, KSH_UNWIND_ERROR);
329 				rv = execute(t->left, flags & XERROK);
330 			}
331 		}
332 #ifdef KSH
333 		else { /* TSELECT */
334 			for (;;) {
335 				if (!(cp = do_selectargs(ap, is_first))) {
336 					rv = 1;
337 					break;
338 				}
339 				is_first = FALSE;
340 				setstr(global(t->str), cp, KSH_UNWIND_ERROR);
341 				rv = execute(t->left, flags & XERROK);
342 			}
343 		}
344 	    }
345 #endif /* KSH */
346 		break;
347 
348 	  case TWHILE:
349 	  case TUNTIL:
350 		e->type = E_LOOP;
351 		while (1) {
352 			i = ksh_sigsetjmp(e->jbuf, 0);
353 			if (!i)
354 				break;
355 			if ((e->flags&EF_BRKCONT_PASS)
356 			    || (i != LBREAK && i != LCONTIN))
357 			{
358 				quitenv();
359 				unwind(i);
360 			} else if (i == LBREAK) {
361 				rv = 0;
362 				goto Break;
363 			}
364 		}
365 		rv = 0; /* in case of a continue */
366 		while ((execute(t->left, XERROK) == 0) == (t->type == TWHILE))
367 			rv = execute(t->right, flags & XERROK);
368 		break;
369 
370 	  case TIF:
371 	  case TELIF:
372 		if (t->right == NULL)
373 			break;	/* should be error */
374 		rv = execute(t->left, XERROK) == 0 ?
375 			execute(t->right->left, flags & XERROK) :
376 			execute(t->right->right, flags & XERROK);
377 		break;
378 
379 	  case TCASE:
380 		cp = evalstr(t->str, DOTILDE);
381 		for (t = t->left; t != NULL && t->type == TPAT; t = t->right)
382 		    for (ap = t->vars; *ap; ap++)
383 			if ((s = evalstr(*ap, DOTILDE|DOPAT))
384 			    && gmatch(cp, s, FALSE))
385 				goto Found;
386 		break;
387 	  Found:
388 		rv = execute(t->left, flags & XERROK);
389 		break;
390 
391 	  case TBRACE:
392 		rv = execute(t->left, flags & XERROK);
393 		break;
394 
395 	  case TFUNCT:
396 		rv = define(t->str, t);
397 		break;
398 
399 	  case TTIME:
400 		/* Clear XEXEC so nested execute() call doesn't exit
401 		 * (allows "ls -l | time grep foo").
402 		 */
403 		rv = timex(t, flags & ~XEXEC);
404 		break;
405 
406 	  case TEXEC:		/* an eval'd TCOM */
407 		s = t->args[0];
408 		ap = makenv();
409 #ifndef F_SETFD
410 		for (i = 0; i < sizeof(clexec_tab); i++)
411 			if (clexec_tab[i]) {
412 				close(i);
413 				clexec_tab[i] = 0;
414 			}
415 #endif
416 		restoresigs();
417 		cleanup_proc_env();
418 		/* XINTACT bit is for OS2 */
419 		ksh_execve(t->str, t->args, ap, (flags & XINTACT) ? 1 : 0);
420 		if (errno == ENOEXEC)
421 			scriptexec(t, ap);
422 		else
423 			errorf("%s: %s", s, strerror(errno));
424 	}
425     Break:
426 	exstat = rv;
427 
428 	quitenv();		/* restores IO */
429 	if ((flags&XEXEC))
430 		unwind(LEXIT);	/* exit child */
431 	if (rv != 0 && !(flags & XERROK)) {
432 		if (Flag(FERREXIT))
433 			unwind(LERROR);
434 		trapsig(SIGERR_);
435 	}
436 	return rv;
437 }
438 
439 /*
440  * execute simple command
441  */
442 
443 static int
comexec(t,tp,ap,flags)444 comexec(t, tp, ap, flags)
445 	struct op *t;
446 	struct tbl *volatile tp;
447 	register char **ap;
448 	int volatile flags;
449 {
450 	int i;
451 	int rv = 0;
452 	register char *cp;
453 	register char **lastp;
454 	static struct op texec; /* Must be static (XXX but why?) */
455 	int type_flags;
456 	int keepasn_ok;
457 	int fcflags = FC_BI|FC_FUNC|FC_PATH;
458 
459 #ifdef KSH
460 	/* snag the last argument for $_ XXX not the same as at&t ksh,
461 	 * which only seems to set $_ after a newline (but not in
462 	 * functions/dot scripts, but in interactive and scipt) -
463 	 * perhaps save last arg here and set it in shell()?.
464 	 */
465 	if (Flag(FTALKING) && *(lastp = ap)) {
466 		while (*++lastp)
467 			;
468 		/* setstr() can't fail here */
469 		setstr(typeset("_", LOCAL, 0, INTEGER, 0), *--lastp,
470 		       KSH_RETURN_ERROR);
471 	}
472 #endif /* KSH */
473 
474 	/* Deal with the shell builtins builtin, exec and command since
475 	 * they can be followed by other commands.  This must be done before
476 	 * we know if we should create a local block, which must be done
477 	 * before we can do a path search (in case the assignments change
478 	 * PATH).
479 	 * Odd cases:
480 	 *   FOO=bar exec > /dev/null		FOO is kept but not exported
481 	 *   FOO=bar exec foobar		FOO is exported
482 	 *   FOO=bar command exec > /dev/null	FOO is neither kept nor exported
483 	 *   FOO=bar command			FOO is neither kept nor exported
484 	 *   PATH=... foobar			use new PATH in foobar search
485 	 */
486 	keepasn_ok = 1;
487 	while (tp && tp->type == CSHELL) {
488 		fcflags = FC_BI|FC_FUNC|FC_PATH;/* undo effects of command */
489 		if (tp->val.f == c_builtin) {
490 			if ((cp = *++ap) == NULL) {
491 				tp = NULL;
492 				break;
493 			}
494 			tp = findcom(cp, FC_BI);
495 			if (tp == NULL)
496 				errorf("builtin: %s: not a builtin", cp);
497 			continue;
498 		} else if (tp->val.f == c_exec) {
499 			if (ap[1] == NULL)
500 				break;
501 			ap++;
502 			flags |= XEXEC;
503 		} else if (tp->val.f == c_command) {
504 			int optc, saw_p = 0;
505 
506 			/* Ugly dealing with options in two places (here and
507 			 * in c_command(), but such is life)
508 			 */
509 			ksh_getopt_reset(&builtin_opt, 0);
510 			while ((optc = ksh_getopt(ap, &builtin_opt, ":p"))
511 									== 'p')
512 				saw_p = 1;
513 			if (optc != EOF)
514 				break;	/* command -vV or something */
515 			/* don't look for functions */
516 			fcflags = FC_BI|FC_PATH;
517 			if (saw_p) {
518 				if (Flag(FRESTRICTED)) {
519 					warningf(TRUE,
520 						"command -p: restricted");
521 					rv = 1;
522 					goto Leave;
523 				}
524 				fcflags |= FC_DEFPATH;
525 			}
526 			ap += builtin_opt.optind;
527 			/* POSIX says special builtins lose their status
528 			 * if accessed using command.
529 			 */
530 			keepasn_ok = 0;
531 			if (!ap[0]) {
532 				/* ensure command with no args exits with 0 */
533 				subst_exstat = 0;
534 				break;
535 			}
536 		} else
537 			break;
538 		tp = findcom(ap[0], fcflags & (FC_BI|FC_FUNC));
539 	}
540 	if (keepasn_ok && (!ap[0] || (tp && (tp->flag & KEEPASN))))
541 		type_flags = 0;
542 	else {
543 		/* create new variable/function block */
544 		newblock();
545 		/* ksh functions don't keep assignments, POSIX functions do. */
546 		if (keepasn_ok && tp && tp->type == CFUNC
547 		    && !(tp->flag & FKSH))
548 			type_flags = 0;
549 		else
550 			type_flags = LOCAL|LOCAL_COPY|EXPORT;
551 	}
552 	if (Flag(FEXPORT))
553 		type_flags |= EXPORT;
554 	for (i = 0; t->vars[i]; i++) {
555 		cp = evalstr(t->vars[i], DOASNTILDE);
556 		if (Flag(FXTRACE)) {
557 			if (i == 0)
558 				shf_fprintf(shl_out, "%s",
559 					PS4_SUBSTITUTE(str_val(global("PS4"))));
560 			shf_fprintf(shl_out, "%s%s", cp,
561 				t->vars[i + 1] ? space : newline);
562 			if (!t->vars[i + 1])
563 				shf_flush(shl_out);
564 		}
565 		typeset(cp, type_flags, 0, 0, 0);
566 	}
567 
568 	if ((cp = *ap) == NULL) {
569 		rv = subst_exstat;
570 		goto Leave;
571 	} else if (!tp) {
572 		if (Flag(FRESTRICTED) && ksh_strchr_dirsep(cp)) {
573 			warningf(TRUE, "%s: restricted", cp);
574 			rv = 1;
575 			goto Leave;
576 		}
577 		tp = findcom(cp, fcflags);
578 	}
579 
580 	switch (tp->type) {
581 	  case CSHELL:			/* shell built-in */
582 		rv = call_builtin(tp, ap);
583 		break;
584 
585 	  case CFUNC:			/* function call */
586 	  {
587 		volatile int old_xflag;
588 		volatile Tflag old_inuse;
589 		const char *volatile old_kshname;
590 
591 		if (!(tp->flag & ISSET)) {
592 			struct tbl *ftp;
593 
594 			if (!tp->u.fpath) {
595 				if (tp->u2.errno_) {
596 					warningf(TRUE,
597 				"%s: can't find function definition file - %s",
598 						cp, strerror(tp->u2.errno_));
599 					rv = 126;
600 				} else {
601 					warningf(TRUE,
602 				"%s: can't find function definition file", cp);
603 					rv = 127;
604 				}
605 				break;
606 			}
607 			if (include(tp->u.fpath, 0, (char **) 0, 0) < 0) {
608 				warningf(TRUE,
609 			    "%s: can't open function definition file %s - %s",
610 					cp, tp->u.fpath, strerror(errno));
611 				rv = 127;
612 				break;
613 			}
614 			if (!(ftp = findfunc(cp, hash(cp), FALSE))
615 			    || !(ftp->flag & ISSET))
616 			{
617 				warningf(TRUE,
618 					"%s: function not defined by %s",
619 					cp, tp->u.fpath);
620 				rv = 127;
621 				break;
622 			}
623 			tp = ftp;
624 		}
625 
626 		/* ksh functions set $0 to function name, POSIX functions leave
627 		 * $0 unchanged.
628 		 */
629 		old_kshname = kshname;
630 		if (tp->flag & FKSH)
631 			kshname = ap[0];
632 		else
633 			ap[0] = (char *) kshname;
634 		e->loc->argv = ap;
635 		for (i = 0; *ap++ != NULL; i++)
636 			;
637 		e->loc->argc = i - 1;
638 		/* ksh-style functions handle getopts sanely,
639 		 * bourne/posix functions are insane...
640 		 */
641 		if (tp->flag & FKSH) {
642 			e->loc->flags |= BF_DOGETOPTS;
643 			e->loc->getopts_state = user_opt;
644 			getopts_reset(1);
645 		}
646 
647 		old_xflag = Flag(FXTRACE);
648 		Flag(FXTRACE) = tp->flag & TRACE ? TRUE : FALSE;
649 
650 		old_inuse = tp->flag & FINUSE;
651 		tp->flag |= FINUSE;
652 
653 		e->type = E_FUNC;
654 		i = ksh_sigsetjmp(e->jbuf, 0);
655 		if (i == 0) {
656 			/* seems odd to pass XERROK here, but at&t ksh does */
657 			exstat = execute(tp->val.t, flags & XERROK);
658 			i = LRETURN;
659 		}
660 		kshname = old_kshname;
661 		Flag(FXTRACE) = old_xflag;
662 		tp->flag = (tp->flag & ~FINUSE) | old_inuse;
663 		/* Were we deleted while executing?  If so, free the execution
664 		 * tree.  todo: Unfortunately, the table entry is never re-used
665 		 * until the lookup table is expanded.
666 		 */
667 		if ((tp->flag & (FDELETE|FINUSE)) == FDELETE) {
668 			if (tp->flag & ALLOC) {
669 				tp->flag &= ~ALLOC;
670 				tfree(tp->val.t, tp->areap);
671 			}
672 			tp->flag = 0;
673 		}
674 		switch (i) {
675 		  case LRETURN:
676 		  case LERROR:
677 			rv = exstat;
678 			break;
679 		  case LINTR:
680 		  case LEXIT:
681 		  case LLEAVE:
682 		  case LSHELL:
683 			quitenv();
684 			unwind(i);
685 			/*NOTREACHED*/
686 		  default:
687 			quitenv();
688 			internal_errorf(1, "CFUNC %d", i);
689 		}
690 		break;
691 	  }
692 
693 	  case CEXEC:		/* executable command */
694 	  case CTALIAS:		/* tracked alias */
695 		if (!(tp->flag&ISSET)) {
696 			/* errno_ will be set if the named command was found
697 			 * but could not be executed (permissions, no execute
698 			 * bit, directory, etc).  Print out a (hopefully)
699 			 * useful error message and set the exit status to 126.
700 			 */
701 			if (tp->u2.errno_) {
702 				warningf(TRUE, "%s: cannot execute - %s", cp,
703 					strerror(tp->u2.errno_));
704 				rv = 126;	/* POSIX */
705 			} else {
706 				warningf(TRUE, "%s: not found", cp);
707 				rv = 127;
708 			}
709 			break;
710 		}
711 
712 #ifdef KSH
713 		/* set $_ to program's full path */
714 		/* setstr() can't fail here */
715 		setstr(typeset("_", LOCAL|EXPORT, 0, INTEGER, 0), tp->val.s,
716 		       KSH_RETURN_ERROR);
717 #endif /* KSH */
718 
719 		if (flags&XEXEC) {
720 			j_exit();
721 			if (!(flags&XBGND) || Flag(FMONITOR)) {
722 				setexecsig(&sigtraps[SIGINT], SS_RESTORE_ORIG);
723 				setexecsig(&sigtraps[SIGQUIT], SS_RESTORE_ORIG);
724 			}
725 		}
726 
727 		/* to fork we set up a TEXEC node and call execute */
728 		texec.type = TEXEC;
729 		texec.left = t;	/* for tprint */
730 		texec.str = tp->val.s;
731 		texec.args = ap;
732 		rv = exchild(&texec, flags, -1);
733 		break;
734 	}
735   Leave:
736 	if (flags & XEXEC) {
737 		exstat = rv;
738 		unwind(LLEAVE);
739 	}
740 	return rv;
741 }
742 
743 static void
scriptexec(tp,ap)744 scriptexec(tp, ap)
745 	register struct op *tp;
746 	register char **ap;
747 {
748 	char *shell;
749 
750 	shell = str_val(global(EXECSHELL_STR));
751 	if (shell && *shell)
752 		shell = search(shell, path, X_OK, (int *) 0);
753 	if (!shell || !*shell)
754 		shell = EXECSHELL;
755 
756 	*tp->args-- = tp->str;
757 #ifdef	SHARPBANG
758 	{
759 		char buf[LINE];
760 		register char *cp;
761 		register int fd, n;
762 
763 		buf[0] = '\0';
764 		if ((fd = open(tp->str, O_RDONLY)) >= 0) {
765 			if ((n = read(fd, buf, LINE - 1)) > 0)
766 				buf[n] = '\0';
767 			(void) close(fd);
768 		}
769 		if ((buf[0] == '#' && buf[1] == '!' && (cp = &buf[2]))
770 # ifdef OS2
771 		    || (strncmp(buf, "extproc", 7) == 0 && isspace(buf[7])
772 			&& (cp = &buf[7]))
773 # endif /* OS2 */
774 		    )
775 		{
776 			while (*cp && (*cp == ' ' || *cp == '\t'))
777 				cp++;
778 			if (*cp && *cp != '\n') {
779 				char *a0 = cp, *a1 = (char *) 0;
780 # ifdef OS2
781 				char *a2 = cp;
782 # endif /* OS2 */
783 
784 				while (*cp && *cp != '\n' && *cp != ' '
785 				       && *cp != '\t')
786 				{
787 # ifdef OS2
788 			/* Allow shell search without prepended path
789 			 * if shell with / in pathname cannot be found.
790 			 * Use / explicitly so \ can be used if explicit
791 			 * needs to be forced.
792 			 */
793 					if (*cp == '/')
794 						a2 = cp + 1;
795 # endif /* OS2 */
796 					cp++;
797 				}
798 				if (*cp && *cp != '\n') {
799 					*cp++ = '\0';
800 					while (*cp
801 					       && (*cp == ' ' || *cp == '\t'))
802 						cp++;
803 					if (*cp && *cp != '\n') {
804 						a1 = cp;
805 						/* all one argument */
806 						while (*cp && *cp != '\n')
807 							cp++;
808 					}
809 				}
810 				if (*cp == '\n') {
811 					*cp = '\0';
812 					if (a1)
813 						*tp->args-- = a1;
814 # ifdef OS2
815 					if (a0 != a2) {
816 						char *tmp_a0 = str_nsave(a0,
817 							strlen(a0) + 5, ATEMP);
818 						if (search_access(tmp_a0, X_OK,
819 								(int *) 0))
820 							a0 = a2;
821 						afree(tmp_a0, ATEMP);
822 					}
823 # endif /* OS2 */
824 					shell = a0;
825 				}
826 			}
827 # ifdef OS2
828 		} else {
829 		        /* Use ksh documented shell default if present
830 			 * else use OS2_SHELL which is assumed to need
831 			 * the /c option and '\' as dir separater.
832 			 */
833 		         char *p = shell;
834 
835 			 shell = str_val(global("EXECSHELL"));
836 			 if (shell && *shell)
837 				 shell = search(shell, path, X_OK, (int *) 0);
838 			 if (!shell || !*shell) {
839 				 shell = p;
840 				 *tp->args-- = "/c";
841 				 for (p = tp->str; *p; p++)
842 					 if (*p == '/')
843 						 *p = '\\';
844 			 }
845 # endif /* OS2 */
846 		}
847 	}
848 #endif	/* SHARPBANG */
849 	*tp->args = shell;
850 
851 	ksh_execve(tp->args[0], tp->args, ap, 0);
852 
853 	/* report both the program that was run and the bogus shell */
854 	errorf("%s: %s: %s", tp->str, shell, strerror(errno));
855 }
856 
857 int
shcomexec(wp)858 shcomexec(wp)
859 	register char **wp;
860 {
861 	register struct tbl *tp;
862 
863 	tp = tsearch(&builtins, *wp, hash(*wp));
864 	if (tp == NULL)
865 		internal_errorf(1, "shcomexec: %s", *wp);
866 	return call_builtin(tp, wp);
867 }
868 
869 /*
870  * Search function tables for a function.  If create set, a table entry
871  * is created if none is found.
872  */
873 struct tbl *
findfunc(name,h,create)874 findfunc(name, h, create)
875 	const char *name;
876 	unsigned int h;
877 	int create;
878 {
879 	struct block *l;
880 	struct tbl *tp = (struct tbl *) 0;
881 
882 	for (l = e->loc; l; l = l->next) {
883 		tp = tsearch(&l->funs, name, h);
884 		if (tp)
885 			break;
886 		if (!l->next && create) {
887 			tp = tenter(&l->funs, name, h);
888 			tp->flag = DEFINED;
889 			tp->type = CFUNC;
890 			tp->val.t = (struct op *) 0;
891 			break;
892 		}
893 	}
894 	return tp;
895 }
896 
897 /*
898  * define function.  Returns 1 if function is being undefined (t == 0) and
899  * function did not exist, returns 0 otherwise.
900  */
901 int
define(name,t)902 define(name, t)
903 	const char *name;
904 	struct op *t;
905 {
906 	struct tbl *tp;
907 	int was_set = 0;
908 
909 	while (1) {
910 		tp = findfunc(name, hash(name), TRUE);
911 
912 		if (tp->flag & ISSET)
913 			was_set = 1;
914 		/* If this function is currently being executed, we zap this
915 		 * table entry so findfunc() won't see it
916 		 */
917 		if (tp->flag & FINUSE) {
918 			tp->name[0] = '\0';
919 			tp->flag &= ~DEFINED; /* ensure it won't be found */
920 			tp->flag |= FDELETE;
921 		} else
922 			break;
923 	}
924 
925 	if (tp->flag & ALLOC) {
926 		tp->flag &= ~(ISSET|ALLOC);
927 		tfree(tp->val.t, tp->areap);
928 	}
929 
930 	if (t == NULL) {		/* undefine */
931 		tdelete(tp);
932 		return was_set ? 0 : 1;
933 	}
934 
935 	tp->val.t = tcopy(t->left, tp->areap);
936 	tp->flag |= (ISSET|ALLOC);
937 	if (t->u.ksh_func)
938 		tp->flag |= FKSH;
939 
940 	return 0;
941 }
942 
943 /*
944  * add builtin
945  */
946 void
builtin(name,func)947 builtin(name, func)
948 	const char *name;
949 	int (*func) ARGS((char **));
950 {
951 	register struct tbl *tp;
952 	Tflag flag;
953 
954 	/* see if any flags should be set for this builtin */
955 	for (flag = 0; ; name++) {
956 		if (*name == '=')	/* command does variable assignment */
957 			flag |= KEEPASN;
958 		else if (*name == '*')	/* POSIX special builtin */
959 			flag |= SPEC_BI;
960 		else if (*name == '+')	/* POSIX regular builtin */
961 			flag |= REG_BI;
962 		else
963 			break;
964 	}
965 
966 	tp = tenter(&builtins, name, hash(name));
967 	tp->flag = DEFINED | flag;
968 	tp->type = CSHELL;
969 	tp->val.f = func;
970 }
971 
972 /*
973  * find command
974  * either function, hashed command, or built-in (in that order)
975  */
976 struct tbl *
findcom(name,flags)977 findcom(name, flags)
978 	const char *name;
979 	int	flags;		/* FC_* */
980 {
981 	static struct tbl temp;
982 	unsigned int h = hash(name);
983 	struct tbl *tp = NULL, *tbi;
984 	int insert = Flag(FTRACKALL);	/* insert if not found */
985 	char *fpath;			/* for function autoloading */
986 	char *npath;
987 
988 	if (ksh_strchr_dirsep(name) != NULL) {
989 		insert = 0;
990 		/* prevent FPATH search below */
991 		flags &= ~FC_FUNC;
992 		goto Search;
993 	}
994 	tbi = (flags & FC_BI) ? tsearch(&builtins, name, h) : NULL;
995 	/* POSIX says special builtins first, then functions, then
996 	 * POSIX regular builtins, then search path...
997 	 */
998 	if ((flags & FC_SPECBI) && tbi && (tbi->flag & SPEC_BI))
999 		tp = tbi;
1000 	if (!tp && (flags & FC_FUNC)) {
1001 		tp = findfunc(name, h, FALSE);
1002 		if (tp && !(tp->flag & ISSET)) {
1003 			if ((fpath = str_val(global("FPATH"))) == null) {
1004 				tp->u.fpath = (char *) 0;
1005 				tp->u2.errno_ = 0;
1006 			} else
1007 				tp->u.fpath = search(name, fpath, R_OK,
1008 					&tp->u2.errno_);
1009 		}
1010 	}
1011 	if (!tp && (flags & FC_REGBI) && tbi && (tbi->flag & REG_BI))
1012 		tp = tbi;
1013 	/* todo: posix says non-special/non-regular builtins must
1014 	 * be triggered by some user-controllable means like a
1015 	 * special directory in PATH.  Requires modifications to
1016 	 * the search() function.  Tracked aliases should be
1017 	 * modified to allow tracking of builtin commands.
1018 	 * This should be under control of the FPOSIX flag.
1019 	 * If this is changed, also change c_whence...
1020 	 */
1021 	if (!tp && (flags & FC_UNREGBI) && tbi)
1022 		tp = tbi;
1023 	if (!tp && (flags & FC_PATH) && !(flags & FC_DEFPATH)) {
1024 		tp = tsearch(&taliases, name, h);
1025 		if (tp && (tp->flag & ISSET) && eaccess(tp->val.s, X_OK) != 0) {
1026 			if (tp->flag & ALLOC) {
1027 				tp->flag &= ~ALLOC;
1028 				afree(tp->val.s, APERM);
1029 			}
1030 			tp->flag &= ~ISSET;
1031 		}
1032 	}
1033 
1034   Search:
1035 	if ((!tp || (tp->type == CTALIAS && !(tp->flag&ISSET)))
1036 	    && (flags & FC_PATH))
1037 	{
1038 		if (!tp) {
1039 			if (insert && !(flags & FC_DEFPATH)) {
1040 				tp = tenter(&taliases, name, h);
1041 				tp->type = CTALIAS;
1042 			} else {
1043 				tp = &temp;
1044 				tp->type = CEXEC;
1045 			}
1046 			tp->flag = DEFINED;	/* make ~ISSET */
1047 		}
1048 		npath = search(name, flags & FC_DEFPATH ? def_path : path,
1049 				X_OK, &tp->u2.errno_);
1050 		if (npath) {
1051 			tp->val.s = tp == &temp ? npath : str_save(npath, APERM);
1052 			tp->flag |= ISSET|ALLOC;
1053 		} else if ((flags & FC_FUNC)
1054 			   && (fpath = str_val(global("FPATH"))) != null
1055 			   && (npath = search(name, fpath, R_OK,
1056 					      &tp->u2.errno_)) != (char *) 0)
1057 		{
1058 			/* An undocumented feature of at&t ksh is that it
1059 			 * searches FPATH if a command is not found, even
1060 			 * if the command hasn't been set up as an autoloaded
1061 			 * function (ie, no typeset -uf).
1062 			 */
1063 			tp = &temp;
1064 			tp->type = CFUNC;
1065 			tp->flag = DEFINED; /* make ~ISSET */
1066 			tp->u.fpath = npath;
1067 		}
1068 	}
1069 	return tp;
1070 }
1071 
1072 /*
1073  * flush executable commands with relative paths
1074  */
1075 void
flushcom(all)1076 flushcom(all)
1077 	int all;		/* just relative or all */
1078 {
1079 	struct tbl *tp;
1080 	struct tstate ts;
1081 
1082 	for (twalk(&ts, &taliases); (tp = tnext(&ts)) != NULL; )
1083 		if ((tp->flag&ISSET) && (all || !ISDIRSEP(tp->val.s[0]))) {
1084 			if (tp->flag&ALLOC) {
1085 				tp->flag &= ~(ALLOC|ISSET);
1086 				afree(tp->val.s, APERM);
1087 			}
1088 			tp->flag &= ~ISSET;
1089 		}
1090 }
1091 
1092 /* Check if path is something we want to find.  Returns -1 for failure. */
1093 int
search_access(path,mode,errnop)1094 search_access(path, mode, errnop)
1095 	const char *path;
1096 	int mode;
1097 	int *errnop;		/* set if candidate found, but not suitable */
1098 {
1099 #ifndef OS2
1100 	int ret, err = 0;
1101 	struct stat statb;
1102 
1103 	if (stat(path, &statb) < 0)
1104 		return -1;
1105 	ret = eaccess(path, mode);
1106 	if (ret < 0)
1107 		err = errno; /* File exists, but we can't access it */
1108 	else if (mode == X_OK
1109 		 && (!S_ISREG(statb.st_mode)
1110 		     /* This 'cause access() says root can execute everything */
1111 		     || !(statb.st_mode & (S_IXUSR|S_IXGRP|S_IXOTH))))
1112 	{
1113 		ret = -1;
1114 		err = S_ISDIR(statb.st_mode) ? EISDIR : EACCES;
1115 	}
1116 	if (err && errnop && !*errnop)
1117 		*errnop = err;
1118 	return ret;
1119 #else /* !OS2 */
1120 	/*
1121 	 * NOTE: ASSUMES path can be modified and has enough room at the
1122 	 *       end of the string for a suffix (ie, 4 extra characters).
1123 	 *	 Certain code knows this (eg, eval.c(globit()),
1124 	 *	 exec.c(search())).
1125 	 */
1126 	static char *xsuffixes[] = { ".ksh", ".exe", ".", ".sh", ".cmd",
1127 				     ".com", ".bat", (char *) 0
1128 				   };
1129 	static char *rsuffixes[] = { ".ksh", ".", ".sh", ".cmd", ".bat",
1130 				      (char *) 0
1131 				   };
1132 	int i;
1133 	char *mpath = (char *) path;
1134 	char *tp = mpath + strlen(mpath);
1135 	char *p;
1136 	char **sfx;
1137 
1138 	/* If a suffix has been specified, check if it is one of the
1139 	 * suffixes that indicate the file is executable - if so, change
1140 	 * the access test to R_OK...
1141 	 * This code assumes OS/2 files can have only one suffix...
1142 	 */
1143 	if ((p = strrchr((p = ksh_strrchr_dirsep(mpath)) ? p : mpath, '.'))) {
1144 		if (mode == X_OK)
1145 			mode = R_OK;
1146 		return search_access1(mpath, mode, errnop);
1147 	}
1148 	/* Try appending the various suffixes.  Different suffixes for
1149 	 * read and execute 'cause we don't want to read an executable...
1150 	 */
1151 	sfx = mode == R_OK ? rsuffixes : xsuffixes;
1152 	for (i = 0; sfx[i]; i++) {
1153 		strcpy(tp, p = sfx[i]);
1154 		if (search_access1(mpath, R_OK, errnop) == 0)
1155 			return 0;
1156 		*tp = '\0';
1157 	}
1158 	return -1;
1159 #endif /* !OS2 */
1160 }
1161 
1162 #ifdef OS2
1163 static int
search_access1(path,mode,errnop)1164 search_access1(path, mode, errnop)
1165 	const char *path;
1166 	int mode;
1167 	int *errnop;		/* set if candidate found, but not suitable */
1168 {
1169 	int ret, err = 0;
1170 	struct stat statb;
1171 
1172 	if (stat(path, &statb) < 0)
1173 		return -1;
1174 	ret = eaccess(path, mode);
1175 	if (ret < 0)
1176 		err = errno; /* File exists, but we can't access it */
1177 	else if (!S_ISREG(statb.st_mode)) {
1178 		ret = -1;
1179 		err = S_ISDIR(statb.st_mode) ? EISDIR : EACCES;
1180 	}
1181 	if (err && errnop && !*errnop)
1182 		*errnop = err;
1183 	return ret;
1184 }
1185 #endif /* OS2 */
1186 
1187 /*
1188  * search for command with PATH
1189  */
1190 char *
search(name,path,mode,errnop)1191 search(name, path, mode, errnop)
1192 	const char *name;
1193 	const char *path;
1194 	int mode;		/* R_OK or X_OK */
1195 	int *errnop;		/* set if candidate found, but not suitable */
1196 {
1197 	const char *sp, *p;
1198 	char *xp;
1199 	XString xs;
1200 	int namelen;
1201 
1202 	if (errnop)
1203 		*errnop = 0;
1204 #ifdef OS2
1205 	/* Xinit() allocates 8 additional bytes, so appended suffixes won't
1206 	 * overflow the memory.
1207 	 */
1208 	namelen = strlen(name) + 1;
1209 	Xinit(xs, xp, namelen, ATEMP);
1210 	memcpy(Xstring(xs, xp), name, namelen);
1211 
1212  	if (ksh_strchr_dirsep(name)) {
1213 		if (search_access(Xstring(xs, xp), mode, errnop) >= 0)
1214 			return Xstring(xs, xp); /* not Xclose() - see above */
1215 		Xfree(xs, xp);
1216 		return NULL;
1217 	}
1218 
1219 	/* Look in current context always. (os2 style) */
1220 	if (search_access(Xstring(xs, xp), mode, errnop) == 0)
1221 		return Xstring(xs, xp); /* not Xclose() - xp may be wrong */
1222 #else /* OS2 */
1223 	if (ksh_strchr_dirsep(name)) {
1224 		if (search_access(name, mode, errnop) == 0)
1225 			return (char *) name;
1226 		return NULL;
1227 	}
1228 
1229 	namelen = strlen(name) + 1;
1230 	Xinit(xs, xp, 128, ATEMP);
1231 #endif /* OS2 */
1232 
1233 	sp = path;
1234 	while (sp != NULL) {
1235 		xp = Xstring(xs, xp);
1236 		if (!(p = strchr(sp, PATHSEP)))
1237 			p = sp + strlen(sp);
1238 		if (p != sp) {
1239 			XcheckN(xs, xp, p - sp);
1240 			memcpy(xp, sp, p - sp);
1241 			xp += p - sp;
1242 			*xp++ = DIRSEP;
1243 		}
1244 		sp = p;
1245 		XcheckN(xs, xp, namelen);
1246 		memcpy(xp, name, namelen);
1247  		if (search_access(Xstring(xs, xp), mode, errnop) == 0)
1248 #ifdef OS2
1249  			return Xstring(xs, xp); /* Not Xclose() - see above */
1250 #else /* OS2 */
1251 			return Xclose(xs, xp + namelen);
1252 #endif /* OS2 */
1253 		if (*sp++ == '\0')
1254 			sp = NULL;
1255 	}
1256 	Xfree(xs, xp);
1257 	return NULL;
1258 }
1259 
1260 static int
call_builtin(tp,wp)1261 call_builtin(tp, wp)
1262 	struct tbl *tp;
1263 	char **wp;
1264 {
1265 	int rv;
1266 
1267 	builtin_argv0 = wp[0];
1268 	builtin_flag = tp->flag;
1269 	shf_reopen(1, SHF_WR, shl_stdout);
1270 	shl_stdout_ok = 1;
1271 	ksh_getopt_reset(&builtin_opt, GF_ERROR);
1272 	rv = (*tp->val.f)(wp);
1273 	shf_flush(shl_stdout);
1274 	shl_stdout_ok = 0;
1275 	builtin_flag = 0;
1276 	builtin_argv0 = (char *) 0;
1277 	return rv;
1278 }
1279 
1280 /*
1281  * set up redirection, saving old fd's in e->savefd
1282  */
1283 static int
iosetup(iop,tp)1284 iosetup(iop, tp)
1285 	register struct ioword *iop;
1286 	struct tbl *tp;
1287 {
1288 	register int u = -1;
1289 	char *cp = iop->name;
1290 	int iotype = iop->flag & IOTYPE;
1291 	int do_open = 1, do_close = 0, UNINITIALIZED(flags);
1292 	struct ioword iotmp;
1293 	struct stat statb;
1294 
1295 	if (iotype != IOHERE)
1296 		cp = evalonestr(cp, DOTILDE|(Flag(FTALKING_I) ? DOGLOB : 0));
1297 
1298 	/* Used for tracing and error messages to print expanded cp */
1299 	iotmp = *iop;
1300 	iotmp.name = (iotype == IOHERE) ? (char *) 0 : cp;
1301 	iotmp.flag |= IONAMEXP;
1302 
1303 	if (Flag(FXTRACE))
1304 		shellf("%s%s\n",
1305 			PS4_SUBSTITUTE(str_val(global("PS4"))),
1306 			snptreef((char *) 0, 32, "%R", &iotmp));
1307 
1308 	switch (iotype) {
1309 	  case IOREAD:
1310 		flags = O_RDONLY;
1311 		break;
1312 
1313 	  case IOCAT:
1314 		flags = O_WRONLY | O_APPEND | O_CREAT;
1315 		break;
1316 
1317 	  case IOWRITE:
1318 		flags = O_WRONLY | O_CREAT | O_TRUNC;
1319 		/* The stat() is here to allow redirections to
1320 		 * things like /dev/null without error.
1321 		 */
1322 		if (Flag(FNOCLOBBER) && !(iop->flag & IOCLOB)
1323 		    && (stat(cp, &statb) < 0 || S_ISREG(statb.st_mode)))
1324 			flags |= O_EXCL;
1325 		break;
1326 
1327 	  case IORDWR:
1328 		flags = O_RDWR | O_CREAT;
1329 		break;
1330 
1331 	  case IOHERE:
1332 		do_open = 0;
1333 		/* herein() returns -2 if error has been printed */
1334 		u = herein(iop->heredoc, iop->flag & IOEVAL);
1335 		/* cp may have wrong name */
1336 		break;
1337 
1338 	  case IODUP:
1339 	  {
1340 		const char *emsg;
1341 
1342 		do_open = 0;
1343 		if (*cp == '-' && !cp[1]) {
1344 			u = 1009;	 /* prevent error return below */
1345 			do_close = 1;
1346 		} else if ((u = check_fd(cp,
1347 				X_OK | ((iop->flag & IORDUP) ? R_OK : W_OK),
1348 				&emsg)) < 0)
1349 		{
1350 			warningf(TRUE, "%s: %s",
1351 				snptreef((char *) 0, 32, "%R", &iotmp), emsg);
1352 			return -1;
1353 		}
1354 		break;
1355 	  }
1356 	}
1357 	if (do_open) {
1358 		if (Flag(FRESTRICTED) && (flags & O_CREAT)) {
1359 			warningf(TRUE, "%s: restricted", cp);
1360 			return -1;
1361 		}
1362 		u = open(cp, flags, 0666);
1363 #ifdef OS2
1364 		if (u < 0 && strcmp(cp, "/dev/null") == 0)
1365 			u = open("nul", flags, 0666);
1366 #endif /* OS2 */
1367 	}
1368 	if (u < 0) {
1369 		/* herein() may already have printed message */
1370 		if (u == -1)
1371 			warningf(TRUE, "cannot %s %s: %s",
1372 			       iotype == IODUP ? "dup"
1373 				: (iotype == IOREAD || iotype == IOHERE) ?
1374 				    "open" : "create", cp, strerror(errno));
1375 		return -1;
1376 	}
1377 	/* Do not save if it has already been redirected (i.e. "cat >x >y"). */
1378 	if (e->savefd[iop->unit] == 0)
1379 		/* c_exec() assumes e->savefd[fd] set for any redirections.
1380 		 * Ask savefd() not to close iop->unit - allows error messages
1381 		 * to be seen if iop->unit is 2; also means we can't lose
1382 		 * the fd (eg, both dup2 below and dup2 in restfd() failing).
1383 		 */
1384 		e->savefd[iop->unit] = savefd(iop->unit, 1);
1385 
1386 	if (do_close)
1387 		close(iop->unit);
1388 	else if (u != iop->unit) {
1389 		if (ksh_dup2(u, iop->unit, TRUE) < 0) {
1390 			warningf(TRUE,
1391 				"could not finish (dup) redirection %s: %s",
1392 				snptreef((char *) 0, 32, "%R", &iotmp),
1393 				strerror(errno));
1394 			if (iotype != IODUP)
1395 				close(u);
1396 			return -1;
1397 		}
1398 		if (iotype != IODUP)
1399 			close(u);
1400 #ifdef KSH
1401 		/* Touching any co-process fd in an empty exec
1402 		 * causes the shell to close its copies
1403 		 */
1404 		else if (tp && tp->type == CSHELL && tp->val.f == c_exec) {
1405 			if (iop->flag & IORDUP)	/* possible exec <&p */
1406 				coproc_read_close(u);
1407 			else			/* possible exec >&p */
1408 				coproc_write_close(u);
1409 		}
1410 #endif /* KSH */
1411 	}
1412 	if (u == 2) /* Clear any write errors */
1413 		shf_reopen(2, SHF_WR, shl_out);
1414 	return 0;
1415 }
1416 
1417 /*
1418  * open here document temp file.
1419  * if unquoted here, expand here temp file into second temp file.
1420  */
1421 static int
herein(content,sub)1422 herein(content, sub)
1423 	const char *content;
1424 	int sub;
1425 {
1426 	volatile int fd = -1;
1427 	struct source *s, *volatile osource;
1428 	struct shf *volatile shf;
1429 	struct temp *h;
1430 	int i;
1431 
1432 	/* ksh -c 'cat << EOF' can cause this... */
1433 	if (content == (char *) 0) {
1434 		warningf(TRUE, "here document missing");
1435 		return -2; /* special to iosetup(): don't print error */
1436 	}
1437 
1438 	/* Create temp file to hold content (done before newenv so temp
1439 	 * doesn't get removed too soon).
1440 	 */
1441 	h = maketemp(ATEMP, TT_HEREDOC_EXP, &e->temps);
1442 	if (!(shf = h->shf) || (fd = open(h->name, O_RDONLY, 0)) < 0) {
1443 		warningf(TRUE, "can't %s temporary file %s: %s",
1444 			!shf ? "create" : "open",
1445 			h->name, strerror(errno));
1446 		if (shf)
1447 			shf_close(shf);
1448 		return -2 /* special to iosetup(): don't print error */;
1449 	}
1450 
1451 	osource = source;
1452 	newenv(E_ERRH);
1453 	i = ksh_sigsetjmp(e->jbuf, 0);
1454 	if (i) {
1455 		source = osource;
1456 		quitenv();
1457 		shf_close(shf);	/* after quitenv */
1458 		close(fd);
1459 		return -2; /* special to iosetup(): don't print error */
1460 	}
1461 	if (sub) {
1462 		/* Do substitutions on the content of heredoc */
1463 		s = pushs(SSTRING, ATEMP);
1464 		s->start = s->str = content;
1465 		source = s;
1466 		if (yylex(ONEWORD) != LWORD)
1467 			internal_errorf(1, "herein: yylex");
1468 		source = osource;
1469 		shf_puts(evalstr(yylval.cp, 0), shf);
1470 	} else
1471 		shf_puts(content, shf);
1472 
1473 	quitenv();
1474 
1475 	if (shf_close(shf) == EOF) {
1476 		close(fd);
1477 		warningf(TRUE, "error writing %s: %s", h->name,
1478 			strerror(errno));
1479 		return -2; /* special to iosetup(): don't print error */
1480 	}
1481 
1482 	return fd;
1483 }
1484 
1485 #ifdef KSH
1486 /*
1487  *	ksh special - the select command processing section
1488  *	print the args in column form - assuming that we can
1489  */
1490 static char *
do_selectargs(ap,print_menu)1491 do_selectargs(ap, print_menu)
1492 	register char **ap;
1493 	bool_t print_menu;
1494 {
1495 	static const char *const read_args[] = {
1496 					"read", "-r", "REPLY", (char *) 0
1497 				    };
1498 	char *s;
1499 	int i, argct;
1500 
1501 	for (argct = 0; ap[argct]; argct++)
1502 		;
1503 	while (1) {
1504 		/* Menu is printed if
1505 		 *	- this is the first time around the select loop
1506 		 *	- the user enters a blank line
1507 		 *	- the REPLY parameter is empty
1508 		 */
1509 		if (print_menu || !*str_val(global("REPLY")))
1510 			pr_menu(ap);
1511 		shellf("%s", str_val(global("PS3")));
1512 		if (call_builtin(findcom("read", FC_BI), (char **) read_args))
1513 			return (char *) 0;
1514 		s = str_val(global("REPLY"));
1515 		if (*s) {
1516 			i = atoi(s);
1517 			return (i >= 1 && i <= argct) ? ap[i - 1] : null;
1518 		}
1519 		print_menu = 1;
1520 	}
1521 }
1522 
1523 struct select_menu_info {
1524 	char	*const *args;
1525 	int	arg_width;
1526 	int	num_width;
1527 } info;
1528 
1529 static char *select_fmt_entry ARGS((void *arg, int i, char *buf, int buflen));
1530 
1531 /* format a single select menu item */
1532 static char *
select_fmt_entry(arg,i,buf,buflen)1533 select_fmt_entry(arg, i, buf, buflen)
1534 	void *arg;
1535 	int i;
1536 	char *buf;
1537 	int buflen;
1538 {
1539 	struct select_menu_info *smi = (struct select_menu_info *) arg;
1540 
1541 	shf_snprintf(buf, buflen, "%*d) %s",
1542 		smi->num_width, i + 1, smi->args[i]);
1543 	return buf;
1544 }
1545 
1546 /*
1547  *	print a select style menu
1548  */
1549 int
pr_menu(ap)1550 pr_menu(ap)
1551 	char *const *ap;
1552 {
1553 	struct select_menu_info smi;
1554 	char *const *pp;
1555 	int nwidth, dwidth;
1556 	int i, n;
1557 
1558 	/* Width/column calculations were done once and saved, but this
1559 	 * means select can't be used recursively so we re-calculate each
1560 	 * time (could save in a structure that is returned, but its probably
1561 	 * not worth the bother).
1562 	 */
1563 
1564 	/*
1565 	 * get dimensions of the list
1566 	 */
1567 	for (n = 0, nwidth = 0, pp = ap; *pp; n++, pp++) {
1568 		i = strlen(*pp);
1569 		nwidth = (i > nwidth) ? i : nwidth;
1570 	}
1571 	/*
1572 	 * we will print an index of the form
1573 	 *	%d)
1574 	 * in front of each entry
1575 	 * get the max width of this
1576 	 */
1577 	for (i = n, dwidth = 1; i >= 10; i /= 10)
1578 		dwidth++;
1579 
1580 	smi.args = ap;
1581 	smi.arg_width = nwidth;
1582 	smi.num_width = dwidth;
1583 	print_columns(shl_out, n, select_fmt_entry, (void *) &smi,
1584 		dwidth + nwidth + 2);
1585 
1586 	return n;
1587 }
1588 #endif /* KSH */
1589 #ifdef KSH
1590 
1591 /*
1592  *	[[ ... ]] evaluation routines
1593  */
1594 
1595 extern const char *const dbtest_tokens[];
1596 extern const char db_close[];
1597 
1598 /* Test if the current token is a whatever.  Accepts the current token if
1599  * it is.  Returns 0 if it is not, non-zero if it is (in the case of
1600  * TM_UNOP and TM_BINOP, the returned value is a Test_op).
1601  */
1602 static int
dbteste_isa(te,meta)1603 dbteste_isa(te, meta)
1604 	Test_env *te;
1605 	Test_meta meta;
1606 {
1607 	int ret = 0;
1608 	int uqword;
1609 	char *p;
1610 
1611 	if (!*te->pos.wp)
1612 		return meta == TM_END;
1613 
1614 	/* unquoted word? */
1615 	for (p = *te->pos.wp; *p == CHAR; p += 2)
1616 		;
1617 	uqword = *p == EOS;
1618 
1619 	if (meta == TM_UNOP || meta == TM_BINOP) {
1620 		if (uqword) {
1621 			char buf[8];	/* longer than the longest operator */
1622 			char *q = buf;
1623 			for (p = *te->pos.wp; *p == CHAR
1624 					      && q < &buf[sizeof(buf) - 1];
1625 					      p += 2)
1626 				*q++ = p[1];
1627 			*q = '\0';
1628 			ret = (int) test_isop(te, meta, buf);
1629 		}
1630 	} else if (meta == TM_END)
1631 		ret = 0;
1632 	else
1633 		ret = uqword
1634 			&& strcmp(*te->pos.wp, dbtest_tokens[(int) meta]) == 0;
1635 
1636 	/* Accept the token? */
1637 	if (ret)
1638 		te->pos.wp++;
1639 
1640 	return ret;
1641 }
1642 
1643 static const char *
dbteste_getopnd(te,op,do_eval)1644 dbteste_getopnd(te, op, do_eval)
1645 	Test_env *te;
1646 	Test_op op;
1647 	int do_eval;
1648 {
1649 	char *s = *te->pos.wp;
1650 
1651 	if (!s)
1652 		return (char *) 0;
1653 
1654 	te->pos.wp++;
1655 
1656 	if (!do_eval)
1657 		return null;
1658 
1659 	if (op == TO_STEQL || op == TO_STNEQ)
1660 		s = evalstr(s, DOTILDE | DOPAT);
1661 	else
1662 		s = evalstr(s, DOTILDE);
1663 
1664 	return s;
1665 }
1666 
1667 static int
dbteste_eval(te,op,opnd1,opnd2,do_eval)1668 dbteste_eval(te, op, opnd1, opnd2, do_eval)
1669 	Test_env *te;
1670 	Test_op op;
1671 	const char *opnd1;
1672 	const char *opnd2;
1673 	int do_eval;
1674 {
1675 	return test_eval(te, op, opnd1, opnd2, do_eval);
1676 }
1677 
1678 static void
dbteste_error(te,offset,msg)1679 dbteste_error(te, offset, msg)
1680 	Test_env *te;
1681 	int offset;
1682 	const char *msg;
1683 {
1684 	te->flags |= TEF_ERROR;
1685 	internal_errorf(0, "dbteste_error: %s (offset %d)", msg, offset);
1686 }
1687 #endif /* KSH */
1688