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