Andrew's git / gitweb.git / parse-options.c
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parse-options.con commit Merge branch 'maint' (82527cf)
   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        int argc;
  10        const char *opt;
  11};
  12
  13static inline const char *get_arg(struct optparse_t *p)
  14{
  15        if (p->opt) {
  16                const char *res = p->opt;
  17                p->opt = NULL;
  18                return res;
  19        }
  20        p->argc--;
  21        return *++p->argv;
  22}
  23
  24static inline const char *skip_prefix(const char *str, const char *prefix)
  25{
  26        size_t len = strlen(prefix);
  27        return strncmp(str, prefix, len) ? NULL : str + len;
  28}
  29
  30static int opterror(const struct option *opt, const char *reason, int flags)
  31{
  32        if (flags & OPT_SHORT)
  33                return error("switch `%c' %s", opt->short_name, reason);
  34        if (flags & OPT_UNSET)
  35                return error("option `no-%s' %s", opt->long_name, reason);
  36        return error("option `%s' %s", opt->long_name, reason);
  37}
  38
  39static int get_value(struct optparse_t *p,
  40                     const struct option *opt, int flags)
  41{
  42        const char *s, *arg;
  43        arg = p->opt ? p->opt : (p->argc > 1 ? p->argv[1] : NULL);
  44
  45        if (p->opt && (flags & OPT_UNSET))
  46                return opterror(opt, "takes no value", flags);
  47
  48        switch (opt->type) {
  49        case OPTION_BOOLEAN:
  50                if (!(flags & OPT_SHORT) && p->opt)
  51                        return opterror(opt, "takes no value", flags);
  52                if (flags & OPT_UNSET)
  53                        *(int *)opt->value = 0;
  54                else
  55                        (*(int *)opt->value)++;
  56                return 0;
  57
  58        case OPTION_STRING:
  59                if (flags & OPT_UNSET) {
  60                        *(const char **)opt->value = (const char *)NULL;
  61                        return 0;
  62                }
  63                if (opt->flags & PARSE_OPT_OPTARG && (!arg || *arg == '-')) {
  64                        *(const char **)opt->value = (const char *)opt->defval;
  65                        return 0;
  66                }
  67                if (!arg)
  68                        return opterror(opt, "requires a value", flags);
  69                *(const char **)opt->value = get_arg(p);
  70                return 0;
  71
  72        case OPTION_CALLBACK:
  73                if (flags & OPT_UNSET)
  74                        return (*opt->callback)(opt, NULL, 1);
  75                if (opt->flags & PARSE_OPT_NOARG) {
  76                        if (p->opt && !(flags & OPT_SHORT))
  77                                return opterror(opt, "takes no value", flags);
  78                        return (*opt->callback)(opt, NULL, 0);
  79                }
  80                if (opt->flags & PARSE_OPT_OPTARG && (!arg || *arg == '-'))
  81                        return (*opt->callback)(opt, NULL, 0);
  82                if (!arg)
  83                        return opterror(opt, "requires a value", flags);
  84                return (*opt->callback)(opt, get_arg(p), 0);
  85
  86        case OPTION_INTEGER:
  87                if (flags & OPT_UNSET) {
  88                        *(int *)opt->value = 0;
  89                        return 0;
  90                }
  91                if (opt->flags & PARSE_OPT_OPTARG && (!arg || !isdigit(*arg))) {
  92                        *(int *)opt->value = opt->defval;
  93                        return 0;
  94                }
  95                if (!arg)
  96                        return opterror(opt, "requires a value", flags);
  97                *(int *)opt->value = strtol(get_arg(p), (char **)&s, 10);
  98                if (*s)
  99                        return opterror(opt, "expects a numerical value", flags);
 100                return 0;
 101
 102        default:
 103                die("should not happen, someone must be hit on the forehead");
 104        }
 105}
 106
 107static int parse_short_opt(struct optparse_t *p, const struct option *options)
 108{
 109        for (; options->type != OPTION_END; options++) {
 110                if (options->short_name == *p->opt) {
 111                        p->opt = p->opt[1] ? p->opt + 1 : NULL;
 112                        return get_value(p, options, OPT_SHORT);
 113                }
 114        }
 115        return error("unknown switch `%c'", *p->opt);
 116}
 117
 118static int parse_long_opt(struct optparse_t *p, const char *arg,
 119                          const struct option *options)
 120{
 121        const char *arg_end = strchr(arg, '=');
 122        const struct option *abbrev_option = NULL;
 123        int abbrev_flags = 0;
 124
 125        if (!arg_end)
 126                arg_end = arg + strlen(arg);
 127
 128        for (; options->type != OPTION_END; options++) {
 129                const char *rest;
 130                int flags = 0;
 131
 132                if (!options->long_name)
 133                        continue;
 134
 135                rest = skip_prefix(arg, options->long_name);
 136                if (!rest) {
 137                        /* abbreviated? */
 138                        if (!strncmp(options->long_name, arg, arg_end - arg)) {
 139is_abbreviated:
 140                                if (abbrev_option)
 141                                        return error("Ambiguous option: %s "
 142                                                "(could be --%s%s or --%s%s)",
 143                                                arg,
 144                                                (flags & OPT_UNSET) ?
 145                                                        "no-" : "",
 146                                                options->long_name,
 147                                                (abbrev_flags & OPT_UNSET) ?
 148                                                        "no-" : "",
 149                                                abbrev_option->long_name);
 150                                if (!(flags & OPT_UNSET) && *arg_end)
 151                                        p->opt = arg_end + 1;
 152                                abbrev_option = options;
 153                                abbrev_flags = flags;
 154                                continue;
 155                        }
 156                        /* negated and abbreviated very much? */
 157                        if (!prefixcmp("no-", arg)) {
 158                                flags |= OPT_UNSET;
 159                                goto is_abbreviated;
 160                        }
 161                        /* negated? */
 162                        if (strncmp(arg, "no-", 3))
 163                                continue;
 164                        flags |= OPT_UNSET;
 165                        rest = skip_prefix(arg + 3, options->long_name);
 166                        /* abbreviated and negated? */
 167                        if (!rest && !prefixcmp(options->long_name, arg + 3))
 168                                goto is_abbreviated;
 169                        if (!rest)
 170                                continue;
 171                }
 172                if (*rest) {
 173                        if (*rest != '=')
 174                                continue;
 175                        p->opt = rest + 1;
 176                }
 177                return get_value(p, options, flags);
 178        }
 179        if (abbrev_option)
 180                return get_value(p, abbrev_option, abbrev_flags);
 181        return error("unknown option `%s'", arg);
 182}
 183
 184int parse_options(int argc, const char **argv, const struct option *options,
 185                  const char * const usagestr[], int flags)
 186{
 187        struct optparse_t args = { argv + 1, argc - 1, NULL };
 188        int j = 0;
 189
 190        for (; args.argc; args.argc--, args.argv++) {
 191                const char *arg = args.argv[0];
 192
 193                if (*arg != '-' || !arg[1]) {
 194                        argv[j++] = args.argv[0];
 195                        continue;
 196                }
 197
 198                if (arg[1] != '-') {
 199                        args.opt = arg + 1;
 200                        do {
 201                                if (*args.opt == 'h')
 202                                        usage_with_options(usagestr, options);
 203                                if (parse_short_opt(&args, options) < 0)
 204                                        usage_with_options(usagestr, options);
 205                        } while (args.opt);
 206                        continue;
 207                }
 208
 209                if (!arg[2]) { /* "--" */
 210                        if (!(flags & PARSE_OPT_KEEP_DASHDASH)) {
 211                                args.argc--;
 212                                args.argv++;
 213                        }
 214                        break;
 215                }
 216
 217                if (!strcmp(arg + 2, "help"))
 218                        usage_with_options(usagestr, options);
 219                if (parse_long_opt(&args, arg + 2, options))
 220                        usage_with_options(usagestr, options);
 221        }
 222
 223        memmove(argv + j, args.argv, args.argc * sizeof(*argv));
 224        argv[j + args.argc] = NULL;
 225        return j + args.argc;
 226}
 227
 228#define USAGE_OPTS_WIDTH 24
 229#define USAGE_GAP         2
 230
 231void usage_with_options(const char * const *usagestr,
 232                        const struct option *opts)
 233{
 234        fprintf(stderr, "usage: %s\n", *usagestr++);
 235        while (*usagestr && **usagestr)
 236                fprintf(stderr, "   or: %s\n", *usagestr++);
 237        while (*usagestr)
 238                fprintf(stderr, "    %s\n", *usagestr++);
 239
 240        if (opts->type != OPTION_GROUP)
 241                fputc('\n', stderr);
 242
 243        for (; opts->type != OPTION_END; opts++) {
 244                size_t pos;
 245                int pad;
 246
 247                if (opts->type == OPTION_GROUP) {
 248                        fputc('\n', stderr);
 249                        if (*opts->help)
 250                                fprintf(stderr, "%s\n", opts->help);
 251                        continue;
 252                }
 253
 254                pos = fprintf(stderr, "    ");
 255                if (opts->short_name)
 256                        pos += fprintf(stderr, "-%c", opts->short_name);
 257                if (opts->long_name && opts->short_name)
 258                        pos += fprintf(stderr, ", ");
 259                if (opts->long_name)
 260                        pos += fprintf(stderr, "--%s", opts->long_name);
 261
 262                switch (opts->type) {
 263                case OPTION_INTEGER:
 264                        if (opts->flags & PARSE_OPT_OPTARG)
 265                                pos += fprintf(stderr, " [<n>]");
 266                        else
 267                                pos += fprintf(stderr, " <n>");
 268                        break;
 269                case OPTION_CALLBACK:
 270                        if (opts->flags & PARSE_OPT_NOARG)
 271                                break;
 272                        /* FALLTHROUGH */
 273                case OPTION_STRING:
 274                        if (opts->argh) {
 275                                if (opts->flags & PARSE_OPT_OPTARG)
 276                                        pos += fprintf(stderr, " [<%s>]", opts->argh);
 277                                else
 278                                        pos += fprintf(stderr, " <%s>", opts->argh);
 279                        } else {
 280                                if (opts->flags & PARSE_OPT_OPTARG)
 281                                        pos += fprintf(stderr, " [...]");
 282                                else
 283                                        pos += fprintf(stderr, " ...");
 284                        }
 285                        break;
 286                default:
 287                        break;
 288                }
 289
 290                if (pos <= USAGE_OPTS_WIDTH)
 291                        pad = USAGE_OPTS_WIDTH - pos;
 292                else {
 293                        fputc('\n', stderr);
 294                        pad = USAGE_OPTS_WIDTH;
 295                }
 296                fprintf(stderr, "%*s%s\n", pad + USAGE_GAP, "", opts->help);
 297        }
 298        fputc('\n', stderr);
 299
 300        exit(129);
 301}
 302
 303/*----- some often used options -----*/
 304#include "cache.h"
 305int parse_opt_abbrev_cb(const struct option *opt, const char *arg, int unset)
 306{
 307        int v;
 308
 309        if (!arg) {
 310                v = unset ? 0 : DEFAULT_ABBREV;
 311        } else {
 312                v = strtol(arg, (char **)&arg, 10);
 313                if (*arg)
 314                        return opterror(opt, "expects a numerical value", 0);
 315                if (v && v < MINIMUM_ABBREV)
 316                        v = MINIMUM_ABBREV;
 317                else if (v > 40)
 318                        v = 40;
 319        }
 320        *(int *)(opt->value) = v;
 321        return 0;
 322}