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1 #include "util.h"
2 #include "parse-options.h"
3 #include "cache.h"
4 #include "header.h"
5 
6 #define OPT_SHORT 1
7 #define OPT_UNSET 2
8 
opterror(const struct option * opt,const char * reason,int flags)9 static int opterror(const struct option *opt, const char *reason, int flags)
10 {
11 	if (flags & OPT_SHORT)
12 		return error("switch `%c' %s", opt->short_name, reason);
13 	if (flags & OPT_UNSET)
14 		return error("option `no-%s' %s", opt->long_name, reason);
15 	return error("option `%s' %s", opt->long_name, reason);
16 }
17 
get_arg(struct parse_opt_ctx_t * p,const struct option * opt,int flags,const char ** arg)18 static int get_arg(struct parse_opt_ctx_t *p, const struct option *opt,
19 		   int flags, const char **arg)
20 {
21 	if (p->opt) {
22 		*arg = p->opt;
23 		p->opt = NULL;
24 	} else if ((opt->flags & PARSE_OPT_LASTARG_DEFAULT) && (p->argc == 1 ||
25 		    **(p->argv + 1) == '-')) {
26 		*arg = (const char *)opt->defval;
27 	} else if (p->argc > 1) {
28 		p->argc--;
29 		*arg = *++p->argv;
30 	} else
31 		return opterror(opt, "requires a value", flags);
32 	return 0;
33 }
34 
get_value(struct parse_opt_ctx_t * p,const struct option * opt,int flags)35 static int get_value(struct parse_opt_ctx_t *p,
36 		     const struct option *opt, int flags)
37 {
38 	const char *s, *arg = NULL;
39 	const int unset = flags & OPT_UNSET;
40 
41 	if (unset && p->opt)
42 		return opterror(opt, "takes no value", flags);
43 	if (unset && (opt->flags & PARSE_OPT_NONEG))
44 		return opterror(opt, "isn't available", flags);
45 
46 	if (!(flags & OPT_SHORT) && p->opt) {
47 		switch (opt->type) {
48 		case OPTION_CALLBACK:
49 			if (!(opt->flags & PARSE_OPT_NOARG))
50 				break;
51 			/* FALLTHROUGH */
52 		case OPTION_BOOLEAN:
53 		case OPTION_INCR:
54 		case OPTION_BIT:
55 		case OPTION_SET_UINT:
56 		case OPTION_SET_PTR:
57 			return opterror(opt, "takes no value", flags);
58 		case OPTION_END:
59 		case OPTION_ARGUMENT:
60 		case OPTION_GROUP:
61 		case OPTION_STRING:
62 		case OPTION_INTEGER:
63 		case OPTION_UINTEGER:
64 		case OPTION_LONG:
65 		case OPTION_U64:
66 		default:
67 			break;
68 		}
69 	}
70 
71 	switch (opt->type) {
72 	case OPTION_BIT:
73 		if (unset)
74 			*(int *)opt->value &= ~opt->defval;
75 		else
76 			*(int *)opt->value |= opt->defval;
77 		return 0;
78 
79 	case OPTION_BOOLEAN:
80 		*(bool *)opt->value = unset ? false : true;
81 		if (opt->set)
82 			*(bool *)opt->set = true;
83 		return 0;
84 
85 	case OPTION_INCR:
86 		*(int *)opt->value = unset ? 0 : *(int *)opt->value + 1;
87 		return 0;
88 
89 	case OPTION_SET_UINT:
90 		*(unsigned int *)opt->value = unset ? 0 : opt->defval;
91 		return 0;
92 
93 	case OPTION_SET_PTR:
94 		*(void **)opt->value = unset ? NULL : (void *)opt->defval;
95 		return 0;
96 
97 	case OPTION_STRING:
98 		if (unset)
99 			*(const char **)opt->value = NULL;
100 		else if (opt->flags & PARSE_OPT_OPTARG && !p->opt)
101 			*(const char **)opt->value = (const char *)opt->defval;
102 		else
103 			return get_arg(p, opt, flags, (const char **)opt->value);
104 		return 0;
105 
106 	case OPTION_CALLBACK:
107 		if (unset)
108 			return (*opt->callback)(opt, NULL, 1) ? (-1) : 0;
109 		if (opt->flags & PARSE_OPT_NOARG)
110 			return (*opt->callback)(opt, NULL, 0) ? (-1) : 0;
111 		if (opt->flags & PARSE_OPT_OPTARG && !p->opt)
112 			return (*opt->callback)(opt, NULL, 0) ? (-1) : 0;
113 		if (get_arg(p, opt, flags, &arg))
114 			return -1;
115 		return (*opt->callback)(opt, arg, 0) ? (-1) : 0;
116 
117 	case OPTION_INTEGER:
118 		if (unset) {
119 			*(int *)opt->value = 0;
120 			return 0;
121 		}
122 		if (opt->flags & PARSE_OPT_OPTARG && !p->opt) {
123 			*(int *)opt->value = opt->defval;
124 			return 0;
125 		}
126 		if (get_arg(p, opt, flags, &arg))
127 			return -1;
128 		*(int *)opt->value = strtol(arg, (char **)&s, 10);
129 		if (*s)
130 			return opterror(opt, "expects a numerical value", flags);
131 		return 0;
132 
133 	case OPTION_UINTEGER:
134 		if (unset) {
135 			*(unsigned int *)opt->value = 0;
136 			return 0;
137 		}
138 		if (opt->flags & PARSE_OPT_OPTARG && !p->opt) {
139 			*(unsigned int *)opt->value = opt->defval;
140 			return 0;
141 		}
142 		if (get_arg(p, opt, flags, &arg))
143 			return -1;
144 		*(unsigned int *)opt->value = strtol(arg, (char **)&s, 10);
145 		if (*s)
146 			return opterror(opt, "expects a numerical value", flags);
147 		return 0;
148 
149 	case OPTION_LONG:
150 		if (unset) {
151 			*(long *)opt->value = 0;
152 			return 0;
153 		}
154 		if (opt->flags & PARSE_OPT_OPTARG && !p->opt) {
155 			*(long *)opt->value = opt->defval;
156 			return 0;
157 		}
158 		if (get_arg(p, opt, flags, &arg))
159 			return -1;
160 		*(long *)opt->value = strtol(arg, (char **)&s, 10);
161 		if (*s)
162 			return opterror(opt, "expects a numerical value", flags);
163 		return 0;
164 
165 	case OPTION_U64:
166 		if (unset) {
167 			*(u64 *)opt->value = 0;
168 			return 0;
169 		}
170 		if (opt->flags & PARSE_OPT_OPTARG && !p->opt) {
171 			*(u64 *)opt->value = opt->defval;
172 			return 0;
173 		}
174 		if (get_arg(p, opt, flags, &arg))
175 			return -1;
176 		*(u64 *)opt->value = strtoull(arg, (char **)&s, 10);
177 		if (*s)
178 			return opterror(opt, "expects a numerical value", flags);
179 		return 0;
180 
181 	case OPTION_END:
182 	case OPTION_ARGUMENT:
183 	case OPTION_GROUP:
184 	default:
185 		die("should not happen, someone must be hit on the forehead");
186 	}
187 }
188 
parse_short_opt(struct parse_opt_ctx_t * p,const struct option * options)189 static int parse_short_opt(struct parse_opt_ctx_t *p, const struct option *options)
190 {
191 	for (; options->type != OPTION_END; options++) {
192 		if (options->short_name == *p->opt) {
193 			p->opt = p->opt[1] ? p->opt + 1 : NULL;
194 			return get_value(p, options, OPT_SHORT);
195 		}
196 	}
197 	return -2;
198 }
199 
parse_long_opt(struct parse_opt_ctx_t * p,const char * arg,const struct option * options)200 static int parse_long_opt(struct parse_opt_ctx_t *p, const char *arg,
201                           const struct option *options)
202 {
203 	const char *arg_end = strchr(arg, '=');
204 	const struct option *abbrev_option = NULL, *ambiguous_option = NULL;
205 	int abbrev_flags = 0, ambiguous_flags = 0;
206 
207 	if (!arg_end)
208 		arg_end = arg + strlen(arg);
209 
210 	for (; options->type != OPTION_END; options++) {
211 		const char *rest;
212 		int flags = 0;
213 
214 		if (!options->long_name)
215 			continue;
216 
217 		rest = skip_prefix(arg, options->long_name);
218 		if (options->type == OPTION_ARGUMENT) {
219 			if (!rest)
220 				continue;
221 			if (*rest == '=')
222 				return opterror(options, "takes no value", flags);
223 			if (*rest)
224 				continue;
225 			p->out[p->cpidx++] = arg - 2;
226 			return 0;
227 		}
228 		if (!rest) {
229 			if (!prefixcmp(options->long_name, "no-")) {
230 				/*
231 				 * The long name itself starts with "no-", so
232 				 * accept the option without "no-" so that users
233 				 * do not have to enter "no-no-" to get the
234 				 * negation.
235 				 */
236 				rest = skip_prefix(arg, options->long_name + 3);
237 				if (rest) {
238 					flags |= OPT_UNSET;
239 					goto match;
240 				}
241 				/* Abbreviated case */
242 				if (!prefixcmp(options->long_name + 3, arg)) {
243 					flags |= OPT_UNSET;
244 					goto is_abbreviated;
245 				}
246 			}
247 			/* abbreviated? */
248 			if (!strncmp(options->long_name, arg, arg_end - arg)) {
249 is_abbreviated:
250 				if (abbrev_option) {
251 					/*
252 					 * If this is abbreviated, it is
253 					 * ambiguous. So when there is no
254 					 * exact match later, we need to
255 					 * error out.
256 					 */
257 					ambiguous_option = abbrev_option;
258 					ambiguous_flags = abbrev_flags;
259 				}
260 				if (!(flags & OPT_UNSET) && *arg_end)
261 					p->opt = arg_end + 1;
262 				abbrev_option = options;
263 				abbrev_flags = flags;
264 				continue;
265 			}
266 			/* negated and abbreviated very much? */
267 			if (!prefixcmp("no-", arg)) {
268 				flags |= OPT_UNSET;
269 				goto is_abbreviated;
270 			}
271 			/* negated? */
272 			if (strncmp(arg, "no-", 3))
273 				continue;
274 			flags |= OPT_UNSET;
275 			rest = skip_prefix(arg + 3, options->long_name);
276 			/* abbreviated and negated? */
277 			if (!rest && !prefixcmp(options->long_name, arg + 3))
278 				goto is_abbreviated;
279 			if (!rest)
280 				continue;
281 		}
282 match:
283 		if (*rest) {
284 			if (*rest != '=')
285 				continue;
286 			p->opt = rest + 1;
287 		}
288 		return get_value(p, options, flags);
289 	}
290 
291 	if (ambiguous_option)
292 		return error("Ambiguous option: %s "
293 			"(could be --%s%s or --%s%s)",
294 			arg,
295 			(ambiguous_flags & OPT_UNSET) ?  "no-" : "",
296 			ambiguous_option->long_name,
297 			(abbrev_flags & OPT_UNSET) ?  "no-" : "",
298 			abbrev_option->long_name);
299 	if (abbrev_option)
300 		return get_value(p, abbrev_option, abbrev_flags);
301 	return -2;
302 }
303 
check_typos(const char * arg,const struct option * options)304 static void check_typos(const char *arg, const struct option *options)
305 {
306 	if (strlen(arg) < 3)
307 		return;
308 
309 	if (!prefixcmp(arg, "no-")) {
310 		error ("did you mean `--%s` (with two dashes ?)", arg);
311 		exit(129);
312 	}
313 
314 	for (; options->type != OPTION_END; options++) {
315 		if (!options->long_name)
316 			continue;
317 		if (!prefixcmp(options->long_name, arg)) {
318 			error ("did you mean `--%s` (with two dashes ?)", arg);
319 			exit(129);
320 		}
321 	}
322 }
323 
parse_options_start(struct parse_opt_ctx_t * ctx,int argc,const char ** argv,int flags)324 void parse_options_start(struct parse_opt_ctx_t *ctx,
325 			 int argc, const char **argv, int flags)
326 {
327 	memset(ctx, 0, sizeof(*ctx));
328 	ctx->argc = argc - 1;
329 	ctx->argv = argv + 1;
330 	ctx->out  = argv;
331 	ctx->cpidx = ((flags & PARSE_OPT_KEEP_ARGV0) != 0);
332 	ctx->flags = flags;
333 	if ((flags & PARSE_OPT_KEEP_UNKNOWN) &&
334 	    (flags & PARSE_OPT_STOP_AT_NON_OPTION))
335 		die("STOP_AT_NON_OPTION and KEEP_UNKNOWN don't go together");
336 }
337 
338 static int usage_with_options_internal(const char * const *,
339 				       const struct option *, int);
340 
parse_options_step(struct parse_opt_ctx_t * ctx,const struct option * options,const char * const usagestr[])341 int parse_options_step(struct parse_opt_ctx_t *ctx,
342 		       const struct option *options,
343 		       const char * const usagestr[])
344 {
345 	int internal_help = !(ctx->flags & PARSE_OPT_NO_INTERNAL_HELP);
346 
347 	/* we must reset ->opt, unknown short option leave it dangling */
348 	ctx->opt = NULL;
349 
350 	for (; ctx->argc; ctx->argc--, ctx->argv++) {
351 		const char *arg = ctx->argv[0];
352 
353 		if (*arg != '-' || !arg[1]) {
354 			if (ctx->flags & PARSE_OPT_STOP_AT_NON_OPTION)
355 				break;
356 			ctx->out[ctx->cpidx++] = ctx->argv[0];
357 			continue;
358 		}
359 
360 		if (arg[1] != '-') {
361 			ctx->opt = arg + 1;
362 			if (internal_help && *ctx->opt == 'h')
363 				return usage_with_options_internal(usagestr, options, 0);
364 			switch (parse_short_opt(ctx, options)) {
365 			case -1:
366 				return parse_options_usage(usagestr, options, arg + 1, 1);
367 			case -2:
368 				goto unknown;
369 			default:
370 				break;
371 			}
372 			if (ctx->opt)
373 				check_typos(arg + 1, options);
374 			while (ctx->opt) {
375 				if (internal_help && *ctx->opt == 'h')
376 					return usage_with_options_internal(usagestr, options, 0);
377 				arg = ctx->opt;
378 				switch (parse_short_opt(ctx, options)) {
379 				case -1:
380 					return parse_options_usage(usagestr, options, arg, 1);
381 				case -2:
382 					/* fake a short option thing to hide the fact that we may have
383 					 * started to parse aggregated stuff
384 					 *
385 					 * This is leaky, too bad.
386 					 */
387 					ctx->argv[0] = strdup(ctx->opt - 1);
388 					*(char *)ctx->argv[0] = '-';
389 					goto unknown;
390 				default:
391 					break;
392 				}
393 			}
394 			continue;
395 		}
396 
397 		if (!arg[2]) { /* "--" */
398 			if (!(ctx->flags & PARSE_OPT_KEEP_DASHDASH)) {
399 				ctx->argc--;
400 				ctx->argv++;
401 			}
402 			break;
403 		}
404 
405 		if (internal_help && !strcmp(arg + 2, "help-all"))
406 			return usage_with_options_internal(usagestr, options, 1);
407 		if (internal_help && !strcmp(arg + 2, "help"))
408 			return usage_with_options_internal(usagestr, options, 0);
409 		if (!strcmp(arg + 2, "list-opts"))
410 			return PARSE_OPT_LIST_OPTS;
411 		if (!strcmp(arg + 2, "list-cmds"))
412 			return PARSE_OPT_LIST_SUBCMDS;
413 		switch (parse_long_opt(ctx, arg + 2, options)) {
414 		case -1:
415 			return parse_options_usage(usagestr, options, arg + 2, 0);
416 		case -2:
417 			goto unknown;
418 		default:
419 			break;
420 		}
421 		continue;
422 unknown:
423 		if (!(ctx->flags & PARSE_OPT_KEEP_UNKNOWN))
424 			return PARSE_OPT_UNKNOWN;
425 		ctx->out[ctx->cpidx++] = ctx->argv[0];
426 		ctx->opt = NULL;
427 	}
428 	return PARSE_OPT_DONE;
429 }
430 
parse_options_end(struct parse_opt_ctx_t * ctx)431 int parse_options_end(struct parse_opt_ctx_t *ctx)
432 {
433 	memmove(ctx->out + ctx->cpidx, ctx->argv, ctx->argc * sizeof(*ctx->out));
434 	ctx->out[ctx->cpidx + ctx->argc] = NULL;
435 	return ctx->cpidx + ctx->argc;
436 }
437 
parse_options_subcommand(int argc,const char ** argv,const struct option * options,const char * const subcommands[],const char * usagestr[],int flags)438 int parse_options_subcommand(int argc, const char **argv, const struct option *options,
439 			const char *const subcommands[], const char *usagestr[], int flags)
440 {
441 	struct parse_opt_ctx_t ctx;
442 
443 	perf_header__set_cmdline(argc, argv);
444 
445 	/* build usage string if it's not provided */
446 	if (subcommands && !usagestr[0]) {
447 		struct strbuf buf = STRBUF_INIT;
448 
449 		strbuf_addf(&buf, "perf %s [<options>] {", argv[0]);
450 		for (int i = 0; subcommands[i]; i++) {
451 			if (i)
452 				strbuf_addstr(&buf, "|");
453 			strbuf_addstr(&buf, subcommands[i]);
454 		}
455 		strbuf_addstr(&buf, "}");
456 
457 		usagestr[0] = strdup(buf.buf);
458 		strbuf_release(&buf);
459 	}
460 
461 	parse_options_start(&ctx, argc, argv, flags);
462 	switch (parse_options_step(&ctx, options, usagestr)) {
463 	case PARSE_OPT_HELP:
464 		exit(129);
465 	case PARSE_OPT_DONE:
466 		break;
467 	case PARSE_OPT_LIST_OPTS:
468 		while (options->type != OPTION_END) {
469 			printf("--%s ", options->long_name);
470 			options++;
471 		}
472 		exit(130);
473 	case PARSE_OPT_LIST_SUBCMDS:
474 		for (int i = 0; subcommands[i]; i++)
475 			printf("%s ", subcommands[i]);
476 		exit(130);
477 	default: /* PARSE_OPT_UNKNOWN */
478 		if (ctx.argv[0][1] == '-') {
479 			error("unknown option `%s'", ctx.argv[0] + 2);
480 		} else {
481 			error("unknown switch `%c'", *ctx.opt);
482 		}
483 		usage_with_options(usagestr, options);
484 	}
485 
486 	return parse_options_end(&ctx);
487 }
488 
parse_options(int argc,const char ** argv,const struct option * options,const char * const usagestr[],int flags)489 int parse_options(int argc, const char **argv, const struct option *options,
490 		  const char * const usagestr[], int flags)
491 {
492 	return parse_options_subcommand(argc, argv, options, NULL,
493 					(const char **) usagestr, flags);
494 }
495 
496 #define USAGE_OPTS_WIDTH 24
497 #define USAGE_GAP         2
498 
print_option_help(const struct option * opts,int full)499 static void print_option_help(const struct option *opts, int full)
500 {
501 	size_t pos;
502 	int pad;
503 
504 	if (opts->type == OPTION_GROUP) {
505 		fputc('\n', stderr);
506 		if (*opts->help)
507 			fprintf(stderr, "%s\n", opts->help);
508 		return;
509 	}
510 	if (!full && (opts->flags & PARSE_OPT_HIDDEN))
511 		return;
512 
513 	pos = fprintf(stderr, "    ");
514 	if (opts->short_name)
515 		pos += fprintf(stderr, "-%c", opts->short_name);
516 	else
517 		pos += fprintf(stderr, "    ");
518 
519 	if (opts->long_name && opts->short_name)
520 		pos += fprintf(stderr, ", ");
521 	if (opts->long_name)
522 		pos += fprintf(stderr, "--%s", opts->long_name);
523 
524 	switch (opts->type) {
525 	case OPTION_ARGUMENT:
526 		break;
527 	case OPTION_LONG:
528 	case OPTION_U64:
529 	case OPTION_INTEGER:
530 	case OPTION_UINTEGER:
531 		if (opts->flags & PARSE_OPT_OPTARG)
532 			if (opts->long_name)
533 				pos += fprintf(stderr, "[=<n>]");
534 			else
535 				pos += fprintf(stderr, "[<n>]");
536 		else
537 			pos += fprintf(stderr, " <n>");
538 		break;
539 	case OPTION_CALLBACK:
540 		if (opts->flags & PARSE_OPT_NOARG)
541 			break;
542 		/* FALLTHROUGH */
543 	case OPTION_STRING:
544 		if (opts->argh) {
545 			if (opts->flags & PARSE_OPT_OPTARG)
546 				if (opts->long_name)
547 					pos += fprintf(stderr, "[=<%s>]", opts->argh);
548 				else
549 					pos += fprintf(stderr, "[<%s>]", opts->argh);
550 			else
551 				pos += fprintf(stderr, " <%s>", opts->argh);
552 		} else {
553 			if (opts->flags & PARSE_OPT_OPTARG)
554 				if (opts->long_name)
555 					pos += fprintf(stderr, "[=...]");
556 				else
557 					pos += fprintf(stderr, "[...]");
558 			else
559 				pos += fprintf(stderr, " ...");
560 		}
561 		break;
562 	default: /* OPTION_{BIT,BOOLEAN,SET_UINT,SET_PTR} */
563 	case OPTION_END:
564 	case OPTION_GROUP:
565 	case OPTION_BIT:
566 	case OPTION_BOOLEAN:
567 	case OPTION_INCR:
568 	case OPTION_SET_UINT:
569 	case OPTION_SET_PTR:
570 		break;
571 	}
572 
573 	if (pos <= USAGE_OPTS_WIDTH)
574 		pad = USAGE_OPTS_WIDTH - pos;
575 	else {
576 		fputc('\n', stderr);
577 		pad = USAGE_OPTS_WIDTH;
578 	}
579 	fprintf(stderr, "%*s%s\n", pad + USAGE_GAP, "", opts->help);
580 }
581 
usage_with_options_internal(const char * const * usagestr,const struct option * opts,int full)582 int usage_with_options_internal(const char * const *usagestr,
583 				const struct option *opts, int full)
584 {
585 	if (!usagestr)
586 		return PARSE_OPT_HELP;
587 
588 	fprintf(stderr, "\n usage: %s\n", *usagestr++);
589 	while (*usagestr && **usagestr)
590 		fprintf(stderr, "    or: %s\n", *usagestr++);
591 	while (*usagestr) {
592 		fprintf(stderr, "%s%s\n",
593 				**usagestr ? "    " : "",
594 				*usagestr);
595 		usagestr++;
596 	}
597 
598 	if (opts->type != OPTION_GROUP)
599 		fputc('\n', stderr);
600 
601 	for (  ; opts->type != OPTION_END; opts++)
602 		print_option_help(opts, full);
603 
604 	fputc('\n', stderr);
605 
606 	return PARSE_OPT_HELP;
607 }
608 
usage_with_options(const char * const * usagestr,const struct option * opts)609 void usage_with_options(const char * const *usagestr,
610 			const struct option *opts)
611 {
612 	exit_browser(false);
613 	usage_with_options_internal(usagestr, opts, 0);
614 	exit(129);
615 }
616 
parse_options_usage(const char * const * usagestr,const struct option * opts,const char * optstr,bool short_opt)617 int parse_options_usage(const char * const *usagestr,
618 			const struct option *opts,
619 			const char *optstr, bool short_opt)
620 {
621 	if (!usagestr)
622 		goto opt;
623 
624 	fprintf(stderr, "\n usage: %s\n", *usagestr++);
625 	while (*usagestr && **usagestr)
626 		fprintf(stderr, "    or: %s\n", *usagestr++);
627 	while (*usagestr) {
628 		fprintf(stderr, "%s%s\n",
629 				**usagestr ? "    " : "",
630 				*usagestr);
631 		usagestr++;
632 	}
633 	fputc('\n', stderr);
634 
635 opt:
636 	for (  ; opts->type != OPTION_END; opts++) {
637 		if (short_opt) {
638 			if (opts->short_name == *optstr)
639 				break;
640 			continue;
641 		}
642 
643 		if (opts->long_name == NULL)
644 			continue;
645 
646 		if (!prefixcmp(optstr, opts->long_name))
647 			break;
648 		if (!prefixcmp(optstr, "no-") &&
649 		    !prefixcmp(optstr + 3, opts->long_name))
650 			break;
651 	}
652 
653 	if (opts->type != OPTION_END)
654 		print_option_help(opts, 0);
655 
656 	return PARSE_OPT_HELP;
657 }
658 
659 
parse_opt_verbosity_cb(const struct option * opt,const char * arg __maybe_unused,int unset)660 int parse_opt_verbosity_cb(const struct option *opt,
661 			   const char *arg __maybe_unused,
662 			   int unset)
663 {
664 	int *target = opt->value;
665 
666 	if (unset)
667 		/* --no-quiet, --no-verbose */
668 		*target = 0;
669 	else if (opt->short_name == 'v') {
670 		if (*target >= 0)
671 			(*target)++;
672 		else
673 			*target = 1;
674 	} else {
675 		if (*target <= 0)
676 			(*target)--;
677 		else
678 			*target = -1;
679 	}
680 	return 0;
681 }
682