parse-options.c

   1 #include "git-compat-util.h"
   2 #include "parse-options.h"
   3 #include "cache.h"
   4 #include "commit.h"
   5 #include "color.h"
   6
   7 static int parse_options_usage(struct parse_opt_ctx_t *ctx,
   8                                const char * const *usagestr,
   9                                const struct option *opts, int err);
  10
  11 #define OPT_SHORT 1
  12 #define OPT_UNSET 2
  13
  14 static int optbug(const struct option *opt, const char *reason)
  15 {
  16         if (opt->long_name)
  17                 return error("BUG: option '%s' %s", opt->long_name, reason);
  18         return error("BUG: switch '%c' %s", opt->short_name, reason);
  19 }
  20
  21 static int opterror(const struct option *opt, const char *reason, int flags)
  22 {
  23         if (flags & OPT_SHORT)
  24                 return error("switch `%c' %s", opt->short_name, reason);
  25         if (flags & OPT_UNSET)
  26                 return error("option `no-%s' %s", opt->long_name, reason);
  27         return error("option `%s' %s", opt->long_name, reason);
  28 }
  29
  30 static int get_arg(struct parse_opt_ctx_t *p, const struct option *opt,
  31                    int flags, const char **arg)
  32 {
  33         if (p->opt) {
  34                 *arg = p->opt;
  35                 p->opt = NULL;
  36         } else if (p->argc == 1 && (opt->flags & PARSE_OPT_LASTARG_DEFAULT)) {
  37                 *arg = (const char *)opt->defval;
  38         } else if (p->argc > 1) {
  39                 p->argc--;
  40                 *arg = *++p->argv;
  41         } else
  42                 return opterror(opt, "requires a value", flags);
  43         return 0;
  44 }
  45
  46 static void fix_filename(const char *prefix, const char **file)
  47 {
  48         if (!file || !*file || !prefix || is_absolute_path(*file)
  49             || !strcmp("-", *file))
  50                 return;
  51         *file = xstrdup(prefix_filename(prefix, strlen(prefix), *file));
  52 }
  53
  54 static int get_value(struct parse_opt_ctx_t *p,
  55                      const struct option *opt, int flags)
  56 {
  57         const char *s, *arg;
  58         const int unset = flags & OPT_UNSET;
  59         int err;
  60
  61         if (unset && p->opt)
  62                 return opterror(opt, "takes no value", flags);
  63         if (unset && (opt->flags & PARSE_OPT_NONEG))
  64                 return opterror(opt, "isn't available", flags);
  65         if (!(flags & OPT_SHORT) && p->opt && (opt->flags & PARSE_OPT_NOARG))
  66                 return opterror(opt, "takes no value", flags);
  67
  68         switch (opt->type) {
  69         case OPTION_BIT:
  70                 if (unset)
  71                         *(int *)opt->value &= ~opt->defval;
  72                 else
  73                         *(int *)opt->value |= opt->defval;
  74                 return 0;
  75
  76         case OPTION_NEGBIT:
  77                 if (unset)
  78                         *(int *)opt->value |= opt->defval;
  79                 else
  80                         *(int *)opt->value &= ~opt->defval;
  81                 return 0;
  82
  83         case OPTION_BOOLEAN:
  84                 *(int *)opt->value = unset ? 0 : *(int *)opt->value + 1;
  85                 return 0;
  86
  87         case OPTION_SET_INT:
  88                 *(int *)opt->value = unset ? 0 : opt->defval;
  89                 return 0;
  90
  91         case OPTION_SET_PTR:
  92                 *(void **)opt->value = unset ? NULL : (void *)opt->defval;
  93                 return 0;
  94
  95         case OPTION_STRING:
  96                 if (unset)
  97                         *(const char **)opt->value = NULL;
  98                 else if (opt->flags & PARSE_OPT_OPTARG && !p->opt)
  99                         *(const char **)opt->value = (const char *)opt->defval;
 100                 else
 101                         return get_arg(p, opt, flags, (const char **)opt->value);
 102                 return 0;
 103
 104         case OPTION_FILENAME:
 105                 err = 0;
 106                 if (unset)
 107                         *(const char **)opt->value = NULL;
 108                 else if (opt->flags & PARSE_OPT_OPTARG && !p->opt)
 109                         *(const char **)opt->value = (const char *)opt->defval;
 110                 else
 111                         err = get_arg(p, opt, flags, (const char **)opt->value);
 112
 113                 if (!err)
 114                         fix_filename(p->prefix, (const char **)opt->value);
 115                 return err;
 116
 117         case OPTION_CALLBACK:
 118                 if (unset)
 119                         return (*opt->callback)(opt, NULL, 1) ? (-1) : 0;
 120                 if (opt->flags & PARSE_OPT_NOARG)
 121                         return (*opt->callback)(opt, NULL, 0) ? (-1) : 0;
 122                 if (opt->flags & PARSE_OPT_OPTARG && !p->opt)
 123                         return (*opt->callback)(opt, NULL, 0) ? (-1) : 0;
 124                 if (get_arg(p, opt, flags, &arg))
 125                         return -1;
 126                 return (*opt->callback)(opt, arg, 0) ? (-1) : 0;
 127
 128         case OPTION_INTEGER:
 129                 if (unset) {
 130                         *(int *)opt->value = 0;
 131                         return 0;
 132                 }
 133                 if (opt->flags & PARSE_OPT_OPTARG && !p->opt) {
 134                         *(int *)opt->value = opt->defval;
 135                         return 0;
 136                 }
 137                 if (get_arg(p, opt, flags, &arg))
 138                         return -1;
 139                 *(int *)opt->value = strtol(arg, (char **)&s, 10);
 140                 if (*s)
 141                         return opterror(opt, "expects a numerical value", flags);
 142                 return 0;
 143
 144         default:
 145                 die("should not happen, someone must be hit on the forehead");
 146         }
 147 }
 148
 149 static int parse_short_opt(struct parse_opt_ctx_t *p, const struct option *options)
 150 {
 151         const struct option *numopt = NULL;
 152
 153         for (; options->type != OPTION_END; options++) {
 154                 if (options->short_name == *p->opt) {
 155                         p->opt = p->opt[1] ? p->opt + 1 : NULL;
 156                         return get_value(p, options, OPT_SHORT);
 157                 }
 158
 159                 /*
 160                  * Handle the numerical option later, explicit one-digit
 161                  * options take precedence over it.
 162                  */
 163                 if (options->type == OPTION_NUMBER)
 164                         numopt = options;
 165         }
 166         if (numopt && isdigit(*p->opt)) {
 167                 size_t len = 1;
 168                 char *arg;
 169                 int rc;
 170
 171                 while (isdigit(p->opt[len]))
 172                         len++;
 173                 arg = xmemdupz(p->opt, len);
 174                 p->opt = p->opt[len] ? p->opt + len : NULL;
 175                 rc = (*numopt->callback)(numopt, arg, 0) ? (-1) : 0;
 176                 free(arg);
 177                 return rc;
 178         }
 179         return -2;
 180 }
 181
 182 static int parse_long_opt(struct parse_opt_ctx_t *p, const char *arg,
 183                           const struct option *options)
 184 {
 185         const char *arg_end = strchr(arg, '=');
 186         const struct option *abbrev_option = NULL, *ambiguous_option = NULL;
 187         int abbrev_flags = 0, ambiguous_flags = 0;
 188
 189         if (!arg_end)
 190                 arg_end = arg + strlen(arg);
 191
 192         for (; options->type != OPTION_END; options++) {
 193                 const char *rest;
 194                 int flags = 0;
 195
 196                 if (!options->long_name)
 197                         continue;
 198
 199                 rest = skip_prefix(arg, options->long_name);
 200                 if (options->type == OPTION_ARGUMENT) {
 201                         if (!rest)
 202                                 continue;
 203                         if (*rest == '=')
 204                                 return opterror(options, "takes no value", flags);
 205                         if (*rest)
 206                                 continue;
 207                         p->out[p->cpidx++] = arg - 2;
 208                         return 0;
 209                 }
 210                 if (!rest) {
 211                         /* abbreviated? */
 212                         if (!strncmp(options->long_name, arg, arg_end - arg)) {
 213 is_abbreviated:
 214                                 if (abbrev_option) {
 215                                         /*
 216                                          * If this is abbreviated, it is
 217                                          * ambiguous. So when there is no
 218                                          * exact match later, we need to
 219                                          * error out.
 220                                          */
 221                                         ambiguous_option = abbrev_option;
 222                                         ambiguous_flags = abbrev_flags;
 223                                 }
 224                                 if (!(flags & OPT_UNSET) && *arg_end)
 225                                         p->opt = arg_end + 1;
 226                                 abbrev_option = options;
 227                                 abbrev_flags = flags;
 228                                 continue;
 229                         }
 230                         /* negation allowed? */
 231                         if (options->flags & PARSE_OPT_NONEG)
 232                                 continue;
 233                         /* negated and abbreviated very much? */
 234                         if (!prefixcmp("no-", arg)) {
 235                                 flags |= OPT_UNSET;
 236                                 goto is_abbreviated;
 237                         }
 238                         /* negated? */
 239                         if (strncmp(arg, "no-", 3))
 240                                 continue;
 241                         flags |= OPT_UNSET;
 242                         rest = skip_prefix(arg + 3, options->long_name);
 243                         /* abbreviated and negated? */
 244                         if (!rest && !prefixcmp(options->long_name, arg + 3))
 245                                 goto is_abbreviated;
 246                         if (!rest)
 247                                 continue;
 248                 }
 249                 if (*rest) {
 250                         if (*rest != '=')
 251                                 continue;
 252                         p->opt = rest + 1;
 253                 }
 254                 return get_value(p, options, flags);
 255         }
 256
 257         if (ambiguous_option)
 258                 return error("Ambiguous option: %s "
 259                         "(could be --%s%s or --%s%s)",
 260                         arg,
 261                         (ambiguous_flags & OPT_UNSET) ?  "no-" : "",
 262                         ambiguous_option->long_name,
 263                         (abbrev_flags & OPT_UNSET) ?  "no-" : "",
 264                         abbrev_option->long_name);
 265         if (abbrev_option)
 266                 return get_value(p, abbrev_option, abbrev_flags);
 267         return -2;
 268 }
 269
 270 static int parse_nodash_opt(struct parse_opt_ctx_t *p, const char *arg,
 271                             const struct option *options)
 272 {
 273         for (; options->type != OPTION_END; options++) {
 274                 if (!(options->flags & PARSE_OPT_NODASH))
 275                         continue;
 276                 if (options->short_name == arg[0] && arg[1] == '\0')
 277                         return get_value(p, options, OPT_SHORT);
 278         }
 279         return -2;
 280 }
 281
 282 static void check_typos(const char *arg, const struct option *options)
 283 {
 284         if (strlen(arg) < 3)
 285                 return;
 286
 287         if (!prefixcmp(arg, "no-")) {
 288                 error ("did you mean `--%s` (with two dashes ?)", arg);
 289                 exit(129);
 290         }
 291
 292         for (; options->type != OPTION_END; options++) {
 293                 if (!options->long_name)
 294                         continue;
 295                 if (!prefixcmp(options->long_name, arg)) {
 296                         error ("did you mean `--%s` (with two dashes ?)", arg);
 297                         exit(129);
 298                 }
 299         }
 300 }
 301
 302 static void parse_options_check(const struct option *opts)
 303 {
 304         int err = 0;
 305
 306         for (; opts->type != OPTION_END; opts++) {
 307                 if ((opts->flags & PARSE_OPT_LASTARG_DEFAULT) &&
 308                     (opts->flags & PARSE_OPT_OPTARG))
 309                         err |= optbug(opts, "uses incompatible flags "
 310                                         "LASTARG_DEFAULT and OPTARG");
 311                 if (opts->flags & PARSE_OPT_NODASH &&
 312                     ((opts->flags & PARSE_OPT_OPTARG) ||
 313                      !(opts->flags & PARSE_OPT_NOARG) ||
 314                      !(opts->flags & PARSE_OPT_NONEG) ||
 315                      opts->long_name))
 316                         err |= optbug(opts, "uses feature "
 317                                         "not supported for dashless options");
 318                 switch (opts->type) {
 319                 case OPTION_BOOLEAN:
 320                 case OPTION_BIT:
 321                 case OPTION_NEGBIT:
 322                 case OPTION_SET_INT:
 323                 case OPTION_SET_PTR:
 324                 case OPTION_NUMBER:
 325                         if ((opts->flags & PARSE_OPT_OPTARG) ||
 326                             !(opts->flags & PARSE_OPT_NOARG))
 327                                 err |= optbug(opts, "should not accept an argument");
 328                 default:
 329                         ; /* ok. (usually accepts an argument) */
 330                 }
 331         }
 332         if (err)
 333                 exit(128);
 334 }
 335
 336 void parse_options_start(struct parse_opt_ctx_t *ctx,
 337                          int argc, const char **argv, const char *prefix,
 338                          const struct option *options, int flags)
 339 {
 340         memset(ctx, 0, sizeof(*ctx));
 341         ctx->argc = argc - 1;
 342         ctx->argv = argv + 1;
 343         ctx->out  = argv;
 344         ctx->prefix = prefix;
 345         ctx->cpidx = ((flags & PARSE_OPT_KEEP_ARGV0) != 0);
 346         ctx->flags = flags;
 347         if ((flags & PARSE_OPT_KEEP_UNKNOWN) &&
 348             (flags & PARSE_OPT_STOP_AT_NON_OPTION))
 349                 die("STOP_AT_NON_OPTION and KEEP_UNKNOWN don't go together");
 350         parse_options_check(options);
 351 }
 352
 353 static int usage_with_options_internal(struct parse_opt_ctx_t *,
 354                                        const char * const *,
 355                                        const struct option *, int, int);
 356
 357 int parse_options_step(struct parse_opt_ctx_t *ctx,
 358                        const struct option *options,
 359                        const char * const usagestr[])
 360 {
 361         int internal_help = !(ctx->flags & PARSE_OPT_NO_INTERNAL_HELP);
 362
 363         /* we must reset ->opt, unknown short option leave it dangling */
 364         ctx->opt = NULL;
 365
 366         for (; ctx->argc; ctx->argc--, ctx->argv++) {
 367                 const char *arg = ctx->argv[0];
 368
 369                 if (*arg != '-' || !arg[1]) {
 370                         if (parse_nodash_opt(ctx, arg, options) == 0)
 371                                 continue;
 372                         if (ctx->flags & PARSE_OPT_STOP_AT_NON_OPTION)
 373                                 break;
 374                         ctx->out[ctx->cpidx++] = ctx->argv[0];
 375                         continue;
 376                 }
 377
 378                 if (arg[1] != '-') {
 379                         ctx->opt = arg + 1;
 380                         if (internal_help && *ctx->opt == 'h')
 381                                 return parse_options_usage(ctx, usagestr, options, 0);
 382                         switch (parse_short_opt(ctx, options)) {
 383                         case -1:
 384                                 return parse_options_usage(ctx, usagestr, options, 1);
 385                         case -2:
 386                                 goto unknown;
 387                         }
 388                         if (ctx->opt)
 389                                 check_typos(arg + 1, options);
 390                         while (ctx->opt) {
 391                                 if (internal_help && *ctx->opt == 'h')
 392                                         return parse_options_usage(ctx, usagestr, options, 0);
 393                                 switch (parse_short_opt(ctx, options)) {
 394                                 case -1:
 395                                         return parse_options_usage(ctx, usagestr, options, 1);
 396                                 case -2:
 397                                         /* fake a short option thing to hide the fact that we may have
 398                                          * started to parse aggregated stuff
 399                                          *
 400                                          * This is leaky, too bad.
 401                                          */
 402                                         ctx->argv[0] = xstrdup(ctx->opt - 1);
 403                                         *(char *)ctx->argv[0] = '-';
 404                                         goto unknown;
 405                                 }
 406                         }
 407                         continue;
 408                 }
 409
 410                 if (!arg[2]) { /* "--" */
 411                         if (!(ctx->flags & PARSE_OPT_KEEP_DASHDASH)) {
 412                                 ctx->argc--;
 413                                 ctx->argv++;
 414                         }
 415                         break;
 416                 }
 417
 418                 if (internal_help && !strcmp(arg + 2, "help-all"))
 419                         return usage_with_options_internal(ctx, usagestr, options, 1, 0);
 420                 if (internal_help && !strcmp(arg + 2, "help"))
 421                         return parse_options_usage(ctx, usagestr, options, 0);
 422                 switch (parse_long_opt(ctx, arg + 2, options)) {
 423                 case -1:
 424                         return parse_options_usage(ctx, usagestr, options, 1);
 425                 case -2:
 426                         goto unknown;
 427                 }
 428                 continue;
 429 unknown:
 430                 if (!(ctx->flags & PARSE_OPT_KEEP_UNKNOWN))
 431                         return PARSE_OPT_UNKNOWN;
 432                 ctx->out[ctx->cpidx++] = ctx->argv[0];
 433                 ctx->opt = NULL;
 434         }
 435         return PARSE_OPT_DONE;
 436 }
 437
 438 int parse_options_end(struct parse_opt_ctx_t *ctx)
 439 {
 440         memmove(ctx->out + ctx->cpidx, ctx->argv, ctx->argc * sizeof(*ctx->out));
 441         ctx->out[ctx->cpidx + ctx->argc] = NULL;
 442         return ctx->cpidx + ctx->argc;
 443 }
 444
 445 int parse_options(int argc, const char **argv, const char *prefix,
 446                   const struct option *options, const char * const usagestr[],
 447                   int flags)
 448 {
 449         struct parse_opt_ctx_t ctx;
 450
 451         parse_options_start(&ctx, argc, argv, prefix, options, flags);
 452         switch (parse_options_step(&ctx, options, usagestr)) {
 453         case PARSE_OPT_HELP:
 454                 exit(129);
 455         case PARSE_OPT_DONE:
 456                 break;
 457         default: /* PARSE_OPT_UNKNOWN */
 458                 if (ctx.argv[0][1] == '-') {
 459                         error("unknown option `%s'", ctx.argv[0] + 2);
 460                 } else {
 461                         error("unknown switch `%c'", *ctx.opt);
 462                 }
 463                 usage_with_options(usagestr, options);
 464         }
 465
 466         return parse_options_end(&ctx);
 467 }
 468
 469 static int usage_argh(const struct option *opts, FILE *outfile)
 470 {
 471         const char *s;
 472         int literal = (opts->flags & PARSE_OPT_LITERAL_ARGHELP) || !opts->argh;
 473         if (opts->flags & PARSE_OPT_OPTARG)
 474                 if (opts->long_name)
 475                         s = literal ? "[=%s]" : "[=<%s>]";
 476                 else
 477                         s = literal ? "[%s]" : "[<%s>]";
 478         else
 479                 s = literal ? " %s" : " <%s>";
 480         return fprintf(outfile, s, opts->argh ? opts->argh : "...");
 481 }
 482
 483 #define USAGE_OPTS_WIDTH 24
 484 #define USAGE_GAP         2
 485
 486 static int usage_with_options_internal(struct parse_opt_ctx_t *ctx,
 487                                        const char * const *usagestr,
 488                                        const struct option *opts, int full, int err)
 489 {
 490         FILE *outfile = err ? stderr : stdout;
 491
 492         if (!usagestr)
 493                 return PARSE_OPT_HELP;
 494
 495         if (!err && ctx && ctx->flags & PARSE_OPT_SHELL_EVAL)
 496                 fprintf(outfile, "cat <<\\EOF\n");
 497
 498         fprintf(outfile, "usage: %s\n", *usagestr++);
 499         while (*usagestr && **usagestr)
 500                 fprintf(outfile, "   or: %s\n", *usagestr++);
 501         while (*usagestr) {
 502                 fprintf(outfile, "%s%s\n",
 503                                 **usagestr ? "    " : "",
 504                                 *usagestr);
 505                 usagestr++;
 506         }
 507
 508         if (opts->type != OPTION_GROUP)
 509                 fputc('\n', outfile);
 510
 511         for (; opts->type != OPTION_END; opts++) {
 512                 size_t pos;
 513                 int pad;
 514
 515                 if (opts->type == OPTION_GROUP) {
 516                         fputc('\n', outfile);
 517                         if (*opts->help)
 518                                 fprintf(outfile, "%s\n", opts->help);
 519                         continue;
 520                 }
 521                 if (!full && (opts->flags & PARSE_OPT_HIDDEN))
 522                         continue;
 523
 524                 pos = fprintf(outfile, "    ");
 525                 if (opts->short_name && !(opts->flags & PARSE_OPT_NEGHELP)) {
 526                         if (opts->flags & PARSE_OPT_NODASH)
 527                                 pos += fprintf(outfile, "%c", opts->short_name);
 528                         else
 529                                 pos += fprintf(outfile, "-%c", opts->short_name);
 530                 }
 531                 if (opts->long_name && opts->short_name)
 532                         pos += fprintf(outfile, ", ");
 533                 if (opts->long_name)
 534                         pos += fprintf(outfile, "--%s%s",
 535                                 (opts->flags & PARSE_OPT_NEGHELP) ?  "no-" : "",
 536                                 opts->long_name);
 537                 if (opts->type == OPTION_NUMBER)
 538                         pos += fprintf(outfile, "-NUM");
 539
 540                 if (!(opts->flags & PARSE_OPT_NOARG))
 541                         pos += usage_argh(opts, outfile);
 542
 543                 if (pos <= USAGE_OPTS_WIDTH)
 544                         pad = USAGE_OPTS_WIDTH - pos;
 545                 else {
 546                         fputc('\n', outfile);
 547                         pad = USAGE_OPTS_WIDTH;
 548                 }
 549                 fprintf(outfile, "%*s%s\n", pad + USAGE_GAP, "", opts->help);
 550         }
 551         fputc('\n', outfile);
 552
 553         if (!err && ctx && ctx->flags & PARSE_OPT_SHELL_EVAL)
 554                 fputs("EOF\n", outfile);
 555
 556         return PARSE_OPT_HELP;
 557 }
 558
 559 void usage_with_options(const char * const *usagestr,
 560                         const struct option *opts)
 561 {
 562         usage_with_options_internal(NULL, usagestr, opts, 0, 1);
 563         exit(129);
 564 }
 565
 566 void usage_msg_opt(const char *msg,
 567                    const char * const *usagestr,
 568                    const struct option *options)
 569 {
 570         fprintf(stderr, "%s\n\n", msg);
 571         usage_with_options(usagestr, options);
 572 }
 573
 574 static int parse_options_usage(struct parse_opt_ctx_t *ctx,
 575                                const char * const *usagestr,
 576                                const struct option *opts, int err)
 577 {
 578         return usage_with_options_internal(ctx, usagestr, opts, 0, err);
 579 }
 580
 581
 582 /*----- some often used options -----*/
 583 #include "cache.h"
 584
 585 int parse_opt_abbrev_cb(const struct option *opt, const char *arg, int unset)
 586 {
 587         int v;
 588
 589         if (!arg) {
 590                 v = unset ? 0 : DEFAULT_ABBREV;
 591         } else {
 592                 v = strtol(arg, (char **)&arg, 10);
 593                 if (*arg)
 594                         return opterror(opt, "expects a numerical value", 0);
 595                 if (v && v < MINIMUM_ABBREV)
 596                         v = MINIMUM_ABBREV;
 597                 else if (v > 40)
 598                         v = 40;
 599         }
 600         *(int *)(opt->value) = v;
 601         return 0;
 602 }
 603
 604 int parse_opt_approxidate_cb(const struct option *opt, const char *arg,
 605                              int unset)
 606 {
 607         *(unsigned long *)(opt->value) = approxidate(arg);
 608         return 0;
 609 }
 610
 611 int parse_opt_color_flag_cb(const struct option *opt, const char *arg,
 612                             int unset)
 613 {
 614         int value;
 615
 616         if (!arg)
 617                 arg = unset ? "never" : (const char *)opt->defval;
 618         value = git_config_colorbool(NULL, arg, -1);
 619         if (value < 0)
 620                 return opterror(opt,
 621                         "expects \"always\", \"auto\", or \"never\"", 0);
 622         *(int *)opt->value = value;
 623         return 0;
 624 }
 625
 626 int parse_opt_verbosity_cb(const struct option *opt, const char *arg,
 627                            int unset)
 628 {
 629         int *target = opt->value;
 630
 631         if (unset)
 632                 /* --no-quiet, --no-verbose */
 633                 *target = 0;
 634         else if (opt->short_name == 'v') {
 635                 if (*target >= 0)
 636                         (*target)++;
 637                 else
 638                         *target = 1;
 639         } else {
 640                 if (*target <= 0)
 641                         (*target)--;
 642                 else
 643                         *target = -1;
 644         }
 645         return 0;
 646 }
 647
 648 int parse_opt_with_commit(const struct option *opt, const char *arg, int unset)
 649 {
 650         unsigned char sha1[20];
 651         struct commit *commit;
 652
 653         if (!arg)
 654                 return -1;
 655         if (get_sha1(arg, sha1))
 656                 return error("malformed object name %s", arg);
 657         commit = lookup_commit_reference(sha1);
 658         if (!commit)
 659                 return error("no such commit %s", arg);
 660         commit_list_insert(commit, opt->value);
 661         return 0;
 662 }
 663
 664 int parse_opt_tertiary(const struct option *opt, const char *arg, int unset)
 665 {
 666         int *target = opt->value;
 667         *target = unset ? 2 : 1;
 668         return 0;
 669 }
 670
 671 int parse_options_concat(struct option *dst, size_t dst_size, struct option *src)
 672 {
 673         int i, j;
 674
 675         for (i = 0; i < dst_size; i++)
 676                 if (dst[i].type == OPTION_END)
 677                         break;
 678         for (j = 0; i < dst_size; i++, j++) {
 679                 dst[i] = src[j];
 680                 if (src[j].type == OPTION_END)
 681                         return 0;
 682         }
 683         return -1;
 684 }