1/*-
2 * Copyright (c) 1991, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 * Copyright (c) 1997-2005
5 *	Herbert Xu <herbert@gondor.apana.org.au>.  All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Kenneth Almquist.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 *    may be used to endorse or promote products derived from this software
20 *    without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35#include <sys/types.h>
36#include <sys/stat.h>
37#include <unistd.h>
38#include <fcntl.h>
39#include <stdlib.h>
40#ifdef HAVE_PATHS_H
41#include <paths.h>
42#endif
43
44/*
45 * When commands are first encountered, they are entered in a hash table.
46 * This ensures that a full path search will not have to be done for them
47 * on each invocation.
48 *
49 * We should investigate converting to a linear search, even though that
50 * would make the command name "hash" a misnomer.
51 */
52
53#include "shell.h"
54#include "main.h"
55#include "nodes.h"
56#include "parser.h"
57#include "redir.h"
58#include "eval.h"
59#include "exec.h"
60#include "builtins.h"
61#include "var.h"
62#include "options.h"
63#include "output.h"
64#include "syntax.h"
65#include "memalloc.h"
66#include "error.h"
67#include "init.h"
68#include "mystring.h"
69#include "show.h"
70#include "jobs.h"
71#include "alias.h"
72#include "system.h"
73
74
75#define CMDTABLESIZE 31		/* should be prime */
76#define ARB 1			/* actual size determined at run time */
77
78
79
80struct tblentry {
81	struct tblentry *next;	/* next entry in hash chain */
82	union param param;	/* definition of builtin function */
83	short cmdtype;		/* index identifying command */
84	char rehash;		/* if set, cd done since entry created */
85	char cmdname[ARB];	/* name of command */
86};
87
88
89STATIC struct tblentry *cmdtable[CMDTABLESIZE];
90STATIC int builtinloc = -1;		/* index in path of %builtin, or -1 */
91
92
93STATIC void tryexec(char *, char **, char **);
94STATIC void printentry(struct tblentry *);
95STATIC void clearcmdentry(int);
96STATIC struct tblentry *cmdlookup(const char *, int);
97STATIC void delete_cmd_entry(void);
98STATIC void addcmdentry(char *, struct cmdentry *);
99STATIC int describe_command(struct output *, char *, const char *, int);
100
101
102/*
103 * Exec a program.  Never returns.  If you change this routine, you may
104 * have to change the find_command routine as well.
105 */
106
107void
108shellexec(char **argv, const char *path, int idx)
109{
110	char *cmdname;
111	int e;
112	char **envp;
113	int exerrno;
114
115	envp = environment();
116	if (strchr(argv[0], '/') != NULL) {
117		tryexec(argv[0], argv, envp);
118		e = errno;
119	} else {
120		e = ENOENT;
121		while ((cmdname = padvance(&path, argv[0])) != NULL) {
122			if (--idx < 0 && pathopt == NULL) {
123				tryexec(cmdname, argv, envp);
124				if (errno != ENOENT && errno != ENOTDIR)
125					e = errno;
126			}
127			stunalloc(cmdname);
128		}
129	}
130
131	/* Map to POSIX errors */
132	switch (e) {
133	case EACCES:
134		exerrno = 126;
135		break;
136	case ENOENT:
137		exerrno = 127;
138		break;
139	default:
140		exerrno = 2;
141		break;
142	}
143	exitstatus = exerrno;
144	TRACE(("shellexec failed for %s, errno %d, suppressint %d\n",
145		argv[0], e, suppressint ));
146	exerror(EXEXIT, "%s: %s", argv[0], errmsg(e, E_EXEC));
147	/* NOTREACHED */
148}
149
150
151STATIC void
152tryexec(char *cmd, char **argv, char **envp)
153{
154	char *const path_bshell = _PATH_BSHELL;
155
156repeat:
157#ifdef SYSV
158	do {
159		execve(cmd, argv, envp);
160	} while (errno == EINTR);
161#else
162	execve(cmd, argv, envp);
163#endif
164	if (cmd != path_bshell && errno == ENOEXEC) {
165		*argv-- = cmd;
166		*argv = cmd = path_bshell;
167		goto repeat;
168	}
169}
170
171
172
173/*
174 * Do a path search.  The variable path (passed by reference) should be
175 * set to the start of the path before the first call; padvance will update
176 * this value as it proceeds.  Successive calls to padvance will return
177 * the possible path expansions in sequence.  If an option (indicated by
178 * a percent sign) appears in the path entry then the global variable
179 * pathopt will be set to point to it; otherwise pathopt will be set to
180 * NULL.
181 */
182
183const char *pathopt;
184
185char *
186padvance(const char **path, const char *name)
187{
188	const char *p;
189	char *q;
190	const char *start;
191	size_t len;
192
193	if (*path == NULL)
194		return NULL;
195	start = *path;
196	for (p = start ; *p && *p != ':' && *p != '%' ; p++);
197	len = p - start + strlen(name) + 2;	/* "2" is for '/' and '\0' */
198	while (stackblocksize() < len)
199		growstackblock();
200	q = stackblock();
201	if (p != start) {
202		memcpy(q, start, p - start);
203		q += p - start;
204		*q++ = '/';
205	}
206	strcpy(q, name);
207	pathopt = NULL;
208	if (*p == '%') {
209		pathopt = ++p;
210		while (*p && *p != ':')  p++;
211	}
212	if (*p == ':')
213		*path = p + 1;
214	else
215		*path = NULL;
216	return stalloc(len);
217}
218
219
220
221/*** Command hashing code ***/
222
223void
224hashiter(void (*fn) (struct cmdentry *, void *), void *token)
225{
226	struct tblentry **pp;
227	struct tblentry *cmdp;
228        struct cmdentry entry;
229	for (pp = cmdtable ; pp < &cmdtable[CMDTABLESIZE] ; pp++) {
230		for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
231			entry.cmdtype = cmdp->cmdtype;
232			entry.u = cmdp->param;
233			fn(&entry, token);
234		}
235	}
236}
237
238int
239hashcmd(int argc, char **argv)
240{
241	struct tblentry **pp;
242	struct tblentry *cmdp;
243	int c;
244	struct cmdentry entry;
245	char *name;
246
247	while ((c = nextopt("r")) != '\0') {
248		clearcmdentry(0);
249		return 0;
250	}
251	if (*argptr == NULL) {
252		for (pp = cmdtable ; pp < &cmdtable[CMDTABLESIZE] ; pp++) {
253			for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
254				if (cmdp->cmdtype == CMDNORMAL)
255					printentry(cmdp);
256			}
257		}
258		return 0;
259	}
260	c = 0;
261	while ((name = *argptr) != NULL) {
262		if ((cmdp = cmdlookup(name, 0)) != NULL
263		 && (cmdp->cmdtype == CMDNORMAL
264		     || (cmdp->cmdtype == CMDBUILTIN && builtinloc >= 0)))
265			delete_cmd_entry();
266		find_command(name, &entry, DO_ERR, pathval());
267		if (entry.cmdtype == CMDUNKNOWN)
268			c = 1;
269		argptr++;
270	}
271	return c;
272}
273
274
275STATIC void
276printentry(struct tblentry *cmdp)
277{
278	int idx;
279	const char *path;
280	char *name;
281
282	idx = cmdp->param.index;
283	path = pathval();
284	do {
285		name = padvance(&path, cmdp->cmdname);
286		stunalloc(name);
287	} while (--idx >= 0);
288	out1str(name);
289	out1fmt(snlfmt, cmdp->rehash ? "*" : nullstr);
290}
291
292
293
294/*
295 * Resolve a command name.  If you change this routine, you may have to
296 * change the shellexec routine as well.
297 */
298
299void
300find_command(char *name, struct cmdentry *entry, int act, const char *path)
301{
302	struct tblentry *cmdp;
303	int idx;
304	int prev;
305	char *fullname;
306	struct stat statb;
307	int e;
308	int updatetbl;
309	struct builtincmd *bcmd;
310
311	/* If name contains a slash, don't use PATH or hash table */
312	if (strchr(name, '/') != NULL) {
313		entry->u.index = -1;
314		if (act & DO_ABS) {
315			while (stat(name, &statb) < 0) {
316#ifdef SYSV
317				if (errno == EINTR)
318					continue;
319#endif
320				entry->cmdtype = CMDUNKNOWN;
321				return;
322			}
323		}
324		entry->cmdtype = CMDNORMAL;
325		return;
326	}
327
328	updatetbl = (path == pathval());
329	if (!updatetbl) {
330		act |= DO_ALTPATH;
331		if (strstr(path, "%builtin") != NULL)
332			act |= DO_ALTBLTIN;
333	}
334
335	/* If name is in the table, check answer will be ok */
336	if ((cmdp = cmdlookup(name, 0)) != NULL) {
337		int bit;
338
339		switch (cmdp->cmdtype) {
340		default:
341#if DEBUG
342			abort();
343#endif
344		case CMDNORMAL:
345			bit = DO_ALTPATH;
346			break;
347		case CMDFUNCTION:
348			bit = DO_NOFUNC;
349			break;
350		case CMDBUILTIN:
351			bit = DO_ALTBLTIN;
352			break;
353		}
354		if (act & bit) {
355			updatetbl = 0;
356			cmdp = NULL;
357		} else if (cmdp->rehash == 0)
358			/* if not invalidated by cd, we're done */
359			goto success;
360	}
361
362	/* If %builtin not in path, check for builtin next */
363	bcmd = find_builtin(name);
364	if (bcmd && !(bcmd->flags & BUILTIN_WEAK) &&
365		(bcmd->flags & BUILTIN_REGULAR || (
366			act & DO_ALTPATH ? !(act & DO_ALTBLTIN) : builtinloc <= 0
367	)))
368		goto builtin_success;
369
370	/* We have to search path. */
371	prev = -1;		/* where to start */
372	if (cmdp && cmdp->rehash) {	/* doing a rehash */
373		if (cmdp->cmdtype == CMDBUILTIN)
374			prev = builtinloc;
375		else
376			prev = cmdp->param.index;
377	}
378
379	e = ENOENT;
380	idx = -1;
381loop:
382	while ((fullname = padvance(&path, name)) != NULL) {
383		stunalloc(fullname);
384		idx++;
385		if (pathopt) {
386			if (prefix(pathopt, "builtin")) {
387				if (bcmd)
388					goto builtin_success;
389				continue;
390			} else if (!(act & DO_NOFUNC) &&
391				   prefix(pathopt, "func")) {
392				/* handled below */
393			} else {
394				/* ignore unimplemented options */
395				continue;
396			}
397		}
398		/* if rehash, don't redo absolute path names */
399		if (fullname[0] == '/' && idx <= prev) {
400			if (idx < prev)
401				continue;
402			TRACE(("searchexec \"%s\": no change\n", name));
403			goto success;
404		}
405		while (stat(fullname, &statb) < 0) {
406#ifdef SYSV
407			if (errno == EINTR)
408				continue;
409#endif
410			if (errno != ENOENT && errno != ENOTDIR)
411				e = errno;
412			goto loop;
413		}
414		e = EACCES;	/* if we fail, this will be the error */
415		if (!S_ISREG(statb.st_mode))
416			continue;
417		if (pathopt) {		/* this is a %func directory */
418			stalloc(strlen(fullname) + 1);
419			readcmdfile(fullname);
420			if ((cmdp = cmdlookup(name, 0)) == NULL ||
421			    cmdp->cmdtype != CMDFUNCTION)
422				sh_error("%s not defined in %s", name,
423					 fullname);
424			stunalloc(fullname);
425			goto success;
426		}
427#ifdef notdef
428		/* XXX this code stops root executing stuff, and is buggy
429		   if you need a group from the group list. */
430		if (statb.st_uid == geteuid()) {
431			if ((statb.st_mode & 0100) == 0)
432				goto loop;
433		} else if (statb.st_gid == getegid()) {
434			if ((statb.st_mode & 010) == 0)
435				goto loop;
436		} else {
437			if ((statb.st_mode & 01) == 0)
438				goto loop;
439		}
440#endif
441		TRACE(("searchexec \"%s\" returns \"%s\"\n", name, fullname));
442		if (!updatetbl) {
443			entry->cmdtype = CMDNORMAL;
444			entry->u.index = idx;
445			return;
446		}
447		INTOFF;
448		cmdp = cmdlookup(name, 1);
449		cmdp->cmdtype = CMDNORMAL;
450		cmdp->param.index = idx;
451		INTON;
452		goto success;
453	}
454
455	if (bcmd && (bcmd->flags & BUILTIN_WEAK))
456		goto builtin_success;
457
458	/* We failed.  If there was an entry for this command, delete it */
459	if (cmdp && updatetbl)
460		delete_cmd_entry();
461	if (act & DO_ERR)
462		sh_warnx("%s: %s", name, errmsg(e, E_EXEC));
463	entry->cmdtype = CMDUNKNOWN;
464	return;
465
466builtin_success:
467	if (!updatetbl) {
468		entry->cmdtype = CMDBUILTIN;
469		entry->u.cmd = bcmd;
470		return;
471	}
472	INTOFF;
473	cmdp = cmdlookup(name, 1);
474	cmdp->cmdtype = CMDBUILTIN;
475	cmdp->param.cmd = bcmd;
476	INTON;
477success:
478	cmdp->rehash = 0;
479	entry->cmdtype = cmdp->cmdtype;
480	entry->u = cmdp->param;
481}
482
483
484
485/*
486 * Search the table of builtin commands.
487 */
488
489struct builtincmd *
490find_builtin(const char *name)
491{
492	struct builtincmd *bp;
493	bp = bsearch(
494		&name, builtincmd, NUMBUILTINS, sizeof(struct builtincmd),
495		pstrcmp
496	);
497	return bp;
498}
499
500
501
502/*
503 * Called when a cd is done.  Marks all commands so the next time they
504 * are executed they will be rehashed.
505 */
506
507void
508hashcd(void)
509{
510	struct tblentry **pp;
511	struct tblentry *cmdp;
512
513	for (pp = cmdtable ; pp < &cmdtable[CMDTABLESIZE] ; pp++) {
514		for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
515			if (cmdp->cmdtype == CMDNORMAL || (
516				cmdp->cmdtype == CMDBUILTIN &&
517				!(cmdp->param.cmd->flags & BUILTIN_REGULAR) &&
518				builtinloc > 0
519			))
520				cmdp->rehash = 1;
521		}
522	}
523}
524
525
526
527/*
528 * Fix command hash table when PATH changed.
529 * Called before PATH is changed.  The argument is the new value of PATH;
530 * pathval() still returns the old value at this point.
531 * Called with interrupts off.
532 */
533
534void
535changepath(const char *newval)
536{
537	const char *old, *new;
538	int idx;
539	int firstchange;
540	int bltin;
541
542	old = pathval();
543	new = newval;
544	firstchange = 9999;	/* assume no change */
545	idx = 0;
546	bltin = -1;
547	for (;;) {
548		if (*old != *new) {
549			firstchange = idx;
550			if ((*old == '\0' && *new == ':')
551			 || (*old == ':' && *new == '\0'))
552				firstchange++;
553			old = new;	/* ignore subsequent differences */
554		}
555		if (*new == '\0')
556			break;
557		if (*new == '%' && bltin < 0 && prefix(new + 1, "builtin"))
558			bltin = idx;
559		if (*new == ':') {
560			idx++;
561		}
562		new++, old++;
563	}
564	if (builtinloc < 0 && bltin >= 0)
565		builtinloc = bltin;		/* zap builtins */
566	if (builtinloc >= 0 && bltin < 0)
567		firstchange = 0;
568	clearcmdentry(firstchange);
569	builtinloc = bltin;
570}
571
572
573/*
574 * Clear out command entries.  The argument specifies the first entry in
575 * PATH which has changed.
576 */
577
578STATIC void
579clearcmdentry(int firstchange)
580{
581	struct tblentry **tblp;
582	struct tblentry **pp;
583	struct tblentry *cmdp;
584
585	INTOFF;
586	for (tblp = cmdtable ; tblp < &cmdtable[CMDTABLESIZE] ; tblp++) {
587		pp = tblp;
588		while ((cmdp = *pp) != NULL) {
589			if ((cmdp->cmdtype == CMDNORMAL &&
590			     cmdp->param.index >= firstchange)
591			 || (cmdp->cmdtype == CMDBUILTIN &&
592			     builtinloc >= firstchange)) {
593				*pp = cmdp->next;
594				ckfree(cmdp);
595			} else {
596				pp = &cmdp->next;
597			}
598		}
599	}
600	INTON;
601}
602
603
604
605/*
606 * Locate a command in the command hash table.  If "add" is nonzero,
607 * add the command to the table if it is not already present.  The
608 * variable "lastcmdentry" is set to point to the address of the link
609 * pointing to the entry, so that delete_cmd_entry can delete the
610 * entry.
611 *
612 * Interrupts must be off if called with add != 0.
613 */
614
615struct tblentry **lastcmdentry;
616
617
618STATIC struct tblentry *
619cmdlookup(const char *name, int add)
620{
621	unsigned int hashval;
622	const char *p;
623	struct tblentry *cmdp;
624	struct tblentry **pp;
625
626	p = name;
627	hashval = (unsigned char)*p << 4;
628	while (*p)
629		hashval += (unsigned char)*p++;
630	hashval &= 0x7FFF;
631	pp = &cmdtable[hashval % CMDTABLESIZE];
632	for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
633		if (equal(cmdp->cmdname, name))
634			break;
635		pp = &cmdp->next;
636	}
637	if (add && cmdp == NULL) {
638		cmdp = *pp = ckmalloc(sizeof (struct tblentry) - ARB
639					+ strlen(name) + 1);
640		cmdp->next = NULL;
641		cmdp->cmdtype = CMDUNKNOWN;
642		strcpy(cmdp->cmdname, name);
643	}
644	lastcmdentry = pp;
645	return cmdp;
646}
647
648/*
649 * Delete the command entry returned on the last lookup.
650 */
651
652STATIC void
653delete_cmd_entry(void)
654{
655	struct tblentry *cmdp;
656
657	INTOFF;
658	cmdp = *lastcmdentry;
659	*lastcmdentry = cmdp->next;
660	if (cmdp->cmdtype == CMDFUNCTION)
661		freefunc(cmdp->param.func);
662	ckfree(cmdp);
663	INTON;
664}
665
666
667
668#ifdef notdef
669void
670getcmdentry(char *name, struct cmdentry *entry)
671{
672	struct tblentry *cmdp = cmdlookup(name, 0);
673
674	if (cmdp) {
675		entry->u = cmdp->param;
676		entry->cmdtype = cmdp->cmdtype;
677	} else {
678		entry->cmdtype = CMDUNKNOWN;
679		entry->u.index = 0;
680	}
681}
682#endif
683
684
685/*
686 * Add a new command entry, replacing any existing command entry for
687 * the same name - except special builtins.
688 */
689
690STATIC void
691addcmdentry(char *name, struct cmdentry *entry)
692{
693	struct tblentry *cmdp;
694
695	cmdp = cmdlookup(name, 1);
696	if (cmdp->cmdtype == CMDFUNCTION) {
697		freefunc(cmdp->param.func);
698	}
699	cmdp->cmdtype = entry->cmdtype;
700	cmdp->param = entry->u;
701	cmdp->rehash = 0;
702}
703
704
705/*
706 * Define a shell function.
707 */
708
709void
710defun(union node *func)
711{
712	struct cmdentry entry;
713
714	INTOFF;
715	entry.cmdtype = CMDFUNCTION;
716	entry.u.func = copyfunc(func);
717	addcmdentry(func->ndefun.text, &entry);
718	INTON;
719}
720
721
722/*
723 * Delete a function if it exists.
724 */
725
726void
727unsetfunc(const char *name)
728{
729	struct tblentry *cmdp;
730
731	if ((cmdp = cmdlookup(name, 0)) != NULL &&
732	    cmdp->cmdtype == CMDFUNCTION)
733		delete_cmd_entry();
734}
735
736/*
737 * Locate and print what a word is...
738 */
739
740int
741typecmd(int argc, char **argv)
742{
743	int i;
744	int err = 0;
745
746	for (i = 1; i < argc; i++) {
747		err |= describe_command(out1, argv[i], NULL, 1);
748	}
749	return err;
750}
751
752STATIC int
753describe_command(out, command, path, verbose)
754	struct output *out;
755	char *command;
756	const char *path;
757	int verbose;
758{
759	struct cmdentry entry;
760	struct tblentry *cmdp;
761	const struct alias *ap;
762
763	path = path ?: pathval();
764
765	if (verbose) {
766		outstr(command, out);
767	}
768
769	/* First look at the keywords */
770	if (findkwd(command)) {
771		outstr(verbose ? " is a shell keyword" : command, out);
772		goto out;
773	}
774
775	/* Then look at the aliases */
776	if ((ap = lookupalias(command, 0)) != NULL) {
777		if (verbose) {
778			outfmt(out, " is an alias for %s", ap->val);
779		} else {
780			outstr("alias ", out);
781			printalias(ap);
782			return 0;
783		}
784		goto out;
785	}
786
787	/* Then check if it is a tracked alias */
788	if ((cmdp = cmdlookup(command, 0)) != NULL) {
789		entry.cmdtype = cmdp->cmdtype;
790		entry.u = cmdp->param;
791	} else {
792		/* Finally use brute force */
793		find_command(command, &entry, DO_ABS, path);
794	}
795
796	switch (entry.cmdtype) {
797	case CMDNORMAL: {
798		int j = entry.u.index;
799		char *p;
800		if (j == -1) {
801			p = command;
802		} else {
803			do {
804				p = padvance(&path, command);
805				stunalloc(p);
806			} while (--j >= 0);
807		}
808		if (verbose) {
809			outfmt(
810				out, " is%s %s",
811				cmdp ? " a tracked alias for" : nullstr, p
812			);
813		} else {
814			outstr(p, out);
815		}
816		break;
817	}
818
819	case CMDFUNCTION:
820		if (verbose) {
821			outstr(" is a shell function", out);
822		} else {
823			outstr(command, out);
824		}
825		break;
826
827	case CMDBUILTIN:
828		if (verbose) {
829			outfmt(
830				out, " is a %sshell builtin",
831				entry.u.cmd->flags & BUILTIN_SPECIAL ?
832					"special " : nullstr
833			);
834		} else {
835			outstr(command, out);
836		}
837		break;
838
839	default:
840		if (verbose) {
841			outstr(": not found\n", out);
842		}
843		return 127;
844	}
845
846out:
847	outc('\n', out);
848	return 0;
849}
850
851int
852commandcmd(argc, argv)
853	int argc;
854	char **argv;
855{
856	char *cmd;
857	int c;
858	enum {
859		VERIFY_BRIEF = 1,
860		VERIFY_VERBOSE = 2,
861	} verify = 0;
862	const char *path = NULL;
863
864	while ((c = nextopt("pvV")) != '\0')
865		if (c == 'V')
866			verify |= VERIFY_VERBOSE;
867		else if (c == 'v')
868			verify |= VERIFY_BRIEF;
869#ifdef DEBUG
870		else if (c != 'p')
871			abort();
872#endif
873		else
874			path = defpath;
875
876	cmd = *argptr;
877	if (verify && cmd)
878		return describe_command(out1, cmd, path, verify - VERIFY_BRIEF);
879
880	return 0;
881}
882