tools/kvm/util/parse-options.c

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