parse-options.c

   1 #include "git-compat-util.h"
   2 #include "parse-options.h"
   3
   4 #define OPT_SHORT 1
   5 #define OPT_UNSET 2
   6
   7 static inline const char *get_arg(struct parse_opt_ctx_t *p)
   8 {
   9         if (p->opt) {
  10                 const char *res = p->opt;
  11                 p->opt = NULL;
  12                 return res;
  13         }
  14         p->argc--;
  15         return *++p->argv;
  16 }
  17
  18 static inline const char *skip_prefix(const char *str, const char *prefix)
  19 {
  20         size_t len = strlen(prefix);
  21         return strncmp(str, prefix, len) ? NULL : str + len;
  22 }
  23
  24 static int opterror(const struct option *opt, const char *reason, int flags)
  25 {
  26         if (flags & OPT_SHORT)
  27                 return error("switch `%c' %s", opt->short_name, reason);
  28         if (flags & OPT_UNSET)
  29                 return error("option `no-%s' %s", opt->long_name, reason);
  30         return error("option `%s' %s", opt->long_name, reason);
  31 }
  32
  33 static int get_value(struct parse_opt_ctx_t *p,
  34                      const struct option *opt, int flags)
  35 {
  36         const char *s, *arg;
  37         const int unset = flags & OPT_UNSET;
  38
  39         if (unset && p->opt)
  40                 return opterror(opt, "takes no value", flags);
  41         if (unset && (opt->flags & PARSE_OPT_NONEG))
  42                 return opterror(opt, "isn't available", flags);
  43
  44         if (!(flags & OPT_SHORT) && p->opt) {
  45                 switch (opt->type) {
  46                 case OPTION_CALLBACK:
  47                         if (!(opt->flags & PARSE_OPT_NOARG))
  48                                 break;
  49                         /* FALLTHROUGH */
  50                 case OPTION_BOOLEAN:
  51                 case OPTION_BIT:
  52                 case OPTION_SET_INT:
  53                 case OPTION_SET_PTR:
  54                         return opterror(opt, "takes no value", flags);
  55                 default:
  56                         break;
  57                 }
  58         }
  59
  60         arg = p->opt ? p->opt : (p->argc > 1 ? p->argv[1] : NULL);
  61         switch (opt->type) {
  62         case OPTION_BIT:
  63                 if (unset)
  64                         *(int *)opt->value &= ~opt->defval;
  65                 else
  66                         *(int *)opt->value |= opt->defval;
  67                 return 0;
  68
  69         case OPTION_BOOLEAN:
  70                 *(int *)opt->value = unset ? 0 : *(int *)opt->value + 1;
  71                 return 0;
  72
  73         case OPTION_SET_INT:
  74                 *(int *)opt->value = unset ? 0 : opt->defval;
  75                 return 0;
  76
  77         case OPTION_SET_PTR:
  78                 *(void **)opt->value = unset ? NULL : (void *)opt->defval;
  79                 return 0;
  80
  81         case OPTION_STRING:
  82                 if (unset) {
  83                         *(const char **)opt->value = NULL;
  84                         return 0;
  85                 }
  86                 if (opt->flags & PARSE_OPT_OPTARG && !p->opt) {
  87                         *(const char **)opt->value = (const char *)opt->defval;
  88                         return 0;
  89                 }
  90                 if (!arg)
  91                         return opterror(opt, "requires a value", flags);
  92                 *(const char **)opt->value = get_arg(p);
  93                 return 0;
  94
  95         case OPTION_CALLBACK:
  96                 if (unset)
  97                         return (*opt->callback)(opt, NULL, 1);
  98                 if (opt->flags & PARSE_OPT_NOARG)
  99                         return (*opt->callback)(opt, NULL, 0);
 100                 if (opt->flags & PARSE_OPT_OPTARG && !p->opt)
 101                         return (*opt->callback)(opt, NULL, 0);
 102                 if (!arg)
 103                         return opterror(opt, "requires a value", flags);
 104                 return (*opt->callback)(opt, get_arg(p), 0);
 105
 106         case OPTION_INTEGER:
 107                 if (unset) {
 108                         *(int *)opt->value = 0;
 109                         return 0;
 110                 }
 111                 if (opt->flags & PARSE_OPT_OPTARG && !p->opt) {
 112                         *(int *)opt->value = opt->defval;
 113                         return 0;
 114                 }
 115                 if (!arg)
 116                         return opterror(opt, "requires a value", flags);
 117                 *(int *)opt->value = strtol(get_arg(p), (char **)&s, 10);
 118                 if (*s)
 119                         return opterror(opt, "expects a numerical value", flags);
 120                 return 0;
 121
 122         default:
 123                 die("should not happen, someone must be hit on the forehead");
 124         }
 125 }
 126
 127 static int parse_short_opt(struct parse_opt_ctx_t *p, const struct option *options)
 128 {
 129         for (; options->type != OPTION_END; options++) {
 130                 if (options->short_name == *p->opt) {
 131                         p->opt = p->opt[1] ? p->opt + 1 : NULL;
 132                         return get_value(p, options, OPT_SHORT);
 133                 }
 134         }
 135         return error("unknown switch `%c'", *p->opt);
 136 }
 137
 138 static int parse_long_opt(struct parse_opt_ctx_t *p, const char *arg,
 139                           const struct option *options)
 140 {
 141         const char *arg_end = strchr(arg, '=');
 142         const struct option *abbrev_option = NULL, *ambiguous_option = NULL;
 143         int abbrev_flags = 0, ambiguous_flags = 0;
 144
 145         if (!arg_end)
 146                 arg_end = arg + strlen(arg);
 147
 148         for (; options->type != OPTION_END; options++) {
 149                 const char *rest;
 150                 int flags = 0;
 151
 152                 if (!options->long_name)
 153                         continue;
 154
 155                 rest = skip_prefix(arg, options->long_name);
 156                 if (options->type == OPTION_ARGUMENT) {
 157                         if (!rest)
 158                                 continue;
 159                         if (*rest == '=')
 160                                 return opterror(options, "takes no value", flags);
 161                         if (*rest)
 162                                 continue;
 163                         p->out[p->cpidx++] = arg - 2;
 164                         return 0;
 165                 }
 166                 if (!rest) {
 167                         /* abbreviated? */
 168                         if (!strncmp(options->long_name, arg, arg_end - arg)) {
 169 is_abbreviated:
 170                                 if (abbrev_option) {
 171                                         /*
 172                                          * If this is abbreviated, it is
 173                                          * ambiguous. So when there is no
 174                                          * exact match later, we need to
 175                                          * error out.
 176                                          */
 177                                         ambiguous_option = abbrev_option;
 178                                         ambiguous_flags = abbrev_flags;
 179                                 }
 180                                 if (!(flags & OPT_UNSET) && *arg_end)
 181                                         p->opt = arg_end + 1;
 182                                 abbrev_option = options;
 183                                 abbrev_flags = flags;
 184                                 continue;
 185                         }
 186                         /* negated and abbreviated very much? */
 187                         if (!prefixcmp("no-", arg)) {
 188                                 flags |= OPT_UNSET;
 189                                 goto is_abbreviated;
 190                         }
 191                         /* negated? */
 192                         if (strncmp(arg, "no-", 3))
 193                                 continue;
 194                         flags |= OPT_UNSET;
 195                         rest = skip_prefix(arg + 3, options->long_name);
 196                         /* abbreviated and negated? */
 197                         if (!rest && !prefixcmp(options->long_name, arg + 3))
 198                                 goto is_abbreviated;
 199                         if (!rest)
 200                                 continue;
 201                 }
 202                 if (*rest) {
 203                         if (*rest != '=')
 204                                 continue;
 205                         p->opt = rest + 1;
 206                 }
 207                 return get_value(p, options, flags);
 208         }
 209
 210         if (ambiguous_option)
 211                 return error("Ambiguous option: %s "
 212                         "(could be --%s%s or --%s%s)",
 213                         arg,
 214                         (ambiguous_flags & OPT_UNSET) ?  "no-" : "",
 215                         ambiguous_option->long_name,
 216                         (abbrev_flags & OPT_UNSET) ?  "no-" : "",
 217                         abbrev_option->long_name);
 218         if (abbrev_option)
 219                 return get_value(p, abbrev_option, abbrev_flags);
 220         return error("unknown option `%s'", arg);
 221 }
 222
 223 void check_typos(const char *arg, const struct option *options)
 224 {
 225         if (strlen(arg) < 3)
 226                 return;
 227
 228         if (!prefixcmp(arg, "no-")) {
 229                 error ("did you mean `--%s` (with two dashes ?)", arg);
 230                 exit(129);
 231         }
 232
 233         for (; options->type != OPTION_END; options++) {
 234                 if (!options->long_name)
 235                         continue;
 236                 if (!prefixcmp(options->long_name, arg)) {
 237                         error ("did you mean `--%s` (with two dashes ?)", arg);
 238                         exit(129);
 239                 }
 240         }
 241 }
 242
 243 void parse_options_start(struct parse_opt_ctx_t *ctx,
 244                          int argc, const char **argv, int flags)
 245 {
 246         memset(ctx, 0, sizeof(*ctx));
 247         ctx->argc = argc - 1;
 248         ctx->argv = argv + 1;
 249         ctx->out  = argv;
 250         ctx->flags = flags;
 251 }
 252
 253 int parse_options_end(struct parse_opt_ctx_t *ctx)
 254 {
 255         memmove(ctx->out + ctx->cpidx, ctx->argv, ctx->argc * sizeof(*ctx->out));
 256         ctx->out[ctx->cpidx + ctx->argc] = NULL;
 257         return ctx->cpidx + ctx->argc;
 258 }
 259
 260 static NORETURN void usage_with_options_internal(const char * const *,
 261                                                  const struct option *, int);
 262
 263 int parse_options(int argc, const char **argv, const struct option *options,
 264                   const char * const usagestr[], int flags)
 265 {
 266         struct parse_opt_ctx_t ctx;
 267
 268         parse_options_start(&ctx, argc, argv, flags);
 269         for (; ctx.argc; ctx.argc--, ctx.argv++) {
 270                 const char *arg = ctx.argv[0];
 271
 272                 if (*arg != '-' || !arg[1]) {
 273                         if (ctx.flags & PARSE_OPT_STOP_AT_NON_OPTION)
 274                                 break;
 275                         ctx.out[ctx.cpidx++] = ctx.argv[0];
 276                         continue;
 277                 }
 278
 279                 if (arg[1] != '-') {
 280                         ctx.opt = arg + 1;
 281                         if (*ctx.opt == 'h')
 282                                 usage_with_options(usagestr, options);
 283                         if (parse_short_opt(&ctx, options) < 0)
 284                                 usage_with_options(usagestr, options);
 285                         if (ctx.opt)
 286                                 check_typos(arg + 1, options);
 287                         while (ctx.opt) {
 288                                 if (*ctx.opt == 'h')
 289                                         usage_with_options(usagestr, options);
 290                                 if (parse_short_opt(&ctx, options) < 0)
 291                                         usage_with_options(usagestr, options);
 292                         }
 293                         continue;
 294                 }
 295
 296                 if (!arg[2]) { /* "--" */
 297                         if (!(ctx.flags & PARSE_OPT_KEEP_DASHDASH)) {
 298                                 ctx.argc--;
 299                                 ctx.argv++;
 300                         }
 301                         break;
 302                 }
 303
 304                 if (!strcmp(arg + 2, "help-all"))
 305                         usage_with_options_internal(usagestr, options, 1);
 306                 if (!strcmp(arg + 2, "help"))
 307                         usage_with_options(usagestr, options);
 308                 if (parse_long_opt(&ctx, arg + 2, options))
 309                         usage_with_options(usagestr, options);
 310         }
 311
 312         return parse_options_end(&ctx);
 313 }
 314
 315 #define USAGE_OPTS_WIDTH 24
 316 #define USAGE_GAP         2
 317
 318 void usage_with_options_internal(const char * const *usagestr,
 319                                  const struct option *opts, int full)
 320 {
 321         fprintf(stderr, "usage: %s\n", *usagestr++);
 322         while (*usagestr && **usagestr)
 323                 fprintf(stderr, "   or: %s\n", *usagestr++);
 324         while (*usagestr) {
 325                 fprintf(stderr, "%s%s\n",
 326                                 **usagestr ? "    " : "",
 327                                 *usagestr);
 328                 usagestr++;
 329         }
 330
 331         if (opts->type != OPTION_GROUP)
 332                 fputc('\n', stderr);
 333
 334         for (; opts->type != OPTION_END; opts++) {
 335                 size_t pos;
 336                 int pad;
 337
 338                 if (opts->type == OPTION_GROUP) {
 339                         fputc('\n', stderr);
 340                         if (*opts->help)
 341                                 fprintf(stderr, "%s\n", opts->help);
 342                         continue;
 343                 }
 344                 if (!full && (opts->flags & PARSE_OPT_HIDDEN))
 345                         continue;
 346
 347                 pos = fprintf(stderr, "    ");
 348                 if (opts->short_name)
 349                         pos += fprintf(stderr, "-%c", opts->short_name);
 350                 if (opts->long_name && opts->short_name)
 351                         pos += fprintf(stderr, ", ");
 352                 if (opts->long_name)
 353                         pos += fprintf(stderr, "--%s", opts->long_name);
 354
 355                 switch (opts->type) {
 356                 case OPTION_ARGUMENT:
 357                         break;
 358                 case OPTION_INTEGER:
 359                         if (opts->flags & PARSE_OPT_OPTARG)
 360                                 if (opts->long_name)
 361                                         pos += fprintf(stderr, "[=<n>]");
 362                                 else
 363                                         pos += fprintf(stderr, "[<n>]");
 364                         else
 365                                 pos += fprintf(stderr, " <n>");
 366                         break;
 367                 case OPTION_CALLBACK:
 368                         if (opts->flags & PARSE_OPT_NOARG)
 369                                 break;
 370                         /* FALLTHROUGH */
 371                 case OPTION_STRING:
 372                         if (opts->argh) {
 373                                 if (opts->flags & PARSE_OPT_OPTARG)
 374                                         if (opts->long_name)
 375                                                 pos += fprintf(stderr, "[=<%s>]", opts->argh);
 376                                         else
 377                                                 pos += fprintf(stderr, "[<%s>]", opts->argh);
 378                                 else
 379                                         pos += fprintf(stderr, " <%s>", opts->argh);
 380                         } else {
 381                                 if (opts->flags & PARSE_OPT_OPTARG)
 382                                         if (opts->long_name)
 383                                                 pos += fprintf(stderr, "[=...]");
 384                                         else
 385                                                 pos += fprintf(stderr, "[...]");
 386                                 else
 387                                         pos += fprintf(stderr, " ...");
 388                         }
 389                         break;
 390                 default: /* OPTION_{BIT,BOOLEAN,SET_INT,SET_PTR} */
 391                         break;
 392                 }
 393
 394                 if (pos <= USAGE_OPTS_WIDTH)
 395                         pad = USAGE_OPTS_WIDTH - pos;
 396                 else {
 397                         fputc('\n', stderr);
 398                         pad = USAGE_OPTS_WIDTH;
 399                 }
 400                 fprintf(stderr, "%*s%s\n", pad + USAGE_GAP, "", opts->help);
 401         }
 402         fputc('\n', stderr);
 403
 404         exit(129);
 405 }
 406
 407 void usage_with_options(const char * const *usagestr,
 408                         const struct option *opts)
 409 {
 410         usage_with_options_internal(usagestr, opts, 0);
 411 }
 412
 413 /*----- some often used options -----*/
 414 #include "cache.h"
 415
 416 int parse_opt_abbrev_cb(const struct option *opt, const char *arg, int unset)
 417 {
 418         int v;
 419
 420         if (!arg) {
 421                 v = unset ? 0 : DEFAULT_ABBREV;
 422         } else {
 423                 v = strtol(arg, (char **)&arg, 10);
 424                 if (*arg)
 425                         return opterror(opt, "expects a numerical value", 0);
 426                 if (v && v < MINIMUM_ABBREV)
 427                         v = MINIMUM_ABBREV;
 428                 else if (v > 40)
 429                         v = 40;
 430         }
 431         *(int *)(opt->value) = v;
 432         return 0;
 433 }
 434
 435 int parse_opt_approxidate_cb(const struct option *opt, const char *arg,
 436                              int unset)
 437 {
 438         *(unsigned long *)(opt->value) = approxidate(arg);
 439         return 0;
 440 }