diff options
Diffstat (limited to 'parse-options.c')
| -rw-r--r-- | parse-options.c | 331 |
1 files changed, 331 insertions, 0 deletions
diff --git a/parse-options.c b/parse-options.c new file mode 100644 index 0000000000..15b32f741b --- /dev/null +++ b/parse-options.c @@ -0,0 +1,331 @@ +#include "git-compat-util.h" +#include "parse-options.h" + +#define OPT_SHORT 1 +#define OPT_UNSET 2 + +struct optparse_t { + const char **argv; + int argc; + const char *opt; +}; + +static inline const char *get_arg(struct optparse_t *p) +{ + if (p->opt) { + const char *res = p->opt; + p->opt = NULL; + return res; + } + p->argc--; + return *++p->argv; +} + +static inline const char *skip_prefix(const char *str, const char *prefix) +{ + size_t len = strlen(prefix); + return strncmp(str, prefix, len) ? NULL : str + len; +} + +static int opterror(const struct option *opt, const char *reason, int flags) +{ + if (flags & OPT_SHORT) + return error("switch `%c' %s", opt->short_name, reason); + if (flags & OPT_UNSET) + return error("option `no-%s' %s", opt->long_name, reason); + return error("option `%s' %s", opt->long_name, reason); +} + +static int get_value(struct optparse_t *p, + const struct option *opt, int flags) +{ + const char *s, *arg; + arg = p->opt ? p->opt : (p->argc > 1 ? p->argv[1] : NULL); + + if (p->opt && (flags & OPT_UNSET)) + return opterror(opt, "takes no value", flags); + + switch (opt->type) { + case OPTION_BOOLEAN: + if (!(flags & OPT_SHORT) && p->opt) + return opterror(opt, "takes no value", flags); + if (flags & OPT_UNSET) + *(int *)opt->value = 0; + else + (*(int *)opt->value)++; + return 0; + + case OPTION_STRING: + if (flags & OPT_UNSET) { + *(const char **)opt->value = (const char *)NULL; + return 0; + } + if (opt->flags & PARSE_OPT_OPTARG && (!arg || *arg == '-')) { + *(const char **)opt->value = (const char *)opt->defval; + return 0; + } + if (!arg) + return opterror(opt, "requires a value", flags); + *(const char **)opt->value = get_arg(p); + return 0; + + case OPTION_CALLBACK: + if (flags & OPT_UNSET) + return (*opt->callback)(opt, NULL, 1); + if (opt->flags & PARSE_OPT_NOARG) { + if (p->opt && !(flags & OPT_SHORT)) + return opterror(opt, "takes no value", flags); + return (*opt->callback)(opt, NULL, 0); + } + if (opt->flags & PARSE_OPT_OPTARG && (!arg || *arg == '-')) + return (*opt->callback)(opt, NULL, 0); + if (!arg) + return opterror(opt, "requires a value", flags); + return (*opt->callback)(opt, get_arg(p), 0); + + case OPTION_INTEGER: + if (flags & OPT_UNSET) { + *(int *)opt->value = 0; + return 0; + } + if (opt->flags & PARSE_OPT_OPTARG && (!arg || !isdigit(*arg))) { + *(int *)opt->value = opt->defval; + return 0; + } + if (!arg) + return opterror(opt, "requires a value", flags); + *(int *)opt->value = strtol(get_arg(p), (char **)&s, 10); + if (*s) + return opterror(opt, "expects a numerical value", flags); + return 0; + + default: + die("should not happen, someone must be hit on the forehead"); + } +} + +static int parse_short_opt(struct optparse_t *p, const struct option *options) +{ + for (; options->type != OPTION_END; options++) { + if (options->short_name == *p->opt) { + p->opt = p->opt[1] ? p->opt + 1 : NULL; + return get_value(p, options, OPT_SHORT); + } + } + return error("unknown switch `%c'", *p->opt); +} + +static int parse_long_opt(struct optparse_t *p, const char *arg, + const struct option *options) +{ + const char *arg_end = strchr(arg, '='); + const struct option *abbrev_option = NULL, *ambiguous_option = NULL; + int abbrev_flags = 0, ambiguous_flags = 0; + + if (!arg_end) + arg_end = arg + strlen(arg); + + for (; options->type != OPTION_END; options++) { + const char *rest; + int flags = 0; + + if (!options->long_name) + continue; + + rest = skip_prefix(arg, options->long_name); + if (!rest) { + /* abbreviated? */ + if (!strncmp(options->long_name, arg, arg_end - arg)) { +is_abbreviated: + if (abbrev_option) { + /* + * If this is abbreviated, it is + * ambiguous. So when there is no + * exact match later, we need to + * error out. + */ + ambiguous_option = abbrev_option; + ambiguous_flags = abbrev_flags; + } + if (!(flags & OPT_UNSET) && *arg_end) + p->opt = arg_end + 1; + abbrev_option = options; + abbrev_flags = flags; + continue; + } + /* negated and abbreviated very much? */ + if (!prefixcmp("no-", arg)) { + flags |= OPT_UNSET; + goto is_abbreviated; + } + /* negated? */ + if (strncmp(arg, "no-", 3)) + continue; + flags |= OPT_UNSET; + rest = skip_prefix(arg + 3, options->long_name); + /* abbreviated and negated? */ + if (!rest && !prefixcmp(options->long_name, arg + 3)) + goto is_abbreviated; + if (!rest) + continue; + } + if (*rest) { + if (*rest != '=') + continue; + p->opt = rest + 1; + } + return get_value(p, options, flags); + } + + if (ambiguous_option) + return error("Ambiguous option: %s " + "(could be --%s%s or --%s%s)", + arg, + (ambiguous_flags & OPT_UNSET) ? "no-" : "", + ambiguous_option->long_name, + (abbrev_flags & OPT_UNSET) ? "no-" : "", + abbrev_option->long_name); + if (abbrev_option) + return get_value(p, abbrev_option, abbrev_flags); + return error("unknown option `%s'", arg); +} + +int parse_options(int argc, const char **argv, const struct option *options, + const char * const usagestr[], int flags) +{ + struct optparse_t args = { argv + 1, argc - 1, NULL }; + int j = 0; + + for (; args.argc; args.argc--, args.argv++) { + const char *arg = args.argv[0]; + + if (*arg != '-' || !arg[1]) { + argv[j++] = args.argv[0]; + continue; + } + + if (arg[1] != '-') { + args.opt = arg + 1; + do { + if (*args.opt == 'h') + usage_with_options(usagestr, options); + if (parse_short_opt(&args, options) < 0) + usage_with_options(usagestr, options); + } while (args.opt); + continue; + } + + if (!arg[2]) { /* "--" */ + if (!(flags & PARSE_OPT_KEEP_DASHDASH)) { + args.argc--; + args.argv++; + } + break; + } + + if (!strcmp(arg + 2, "help")) + usage_with_options(usagestr, options); + if (parse_long_opt(&args, arg + 2, options)) + usage_with_options(usagestr, options); + } + + memmove(argv + j, args.argv, args.argc * sizeof(*argv)); + argv[j + args.argc] = NULL; + return j + args.argc; +} + +#define USAGE_OPTS_WIDTH 24 +#define USAGE_GAP 2 + +void usage_with_options(const char * const *usagestr, + const struct option *opts) +{ + fprintf(stderr, "usage: %s\n", *usagestr++); + while (*usagestr && **usagestr) + fprintf(stderr, " or: %s\n", *usagestr++); + while (*usagestr) + fprintf(stderr, " %s\n", *usagestr++); + + if (opts->type != OPTION_GROUP) + fputc('\n', stderr); + + for (; opts->type != OPTION_END; opts++) { + size_t pos; + int pad; + + if (opts->type == OPTION_GROUP) { + fputc('\n', stderr); + if (*opts->help) + fprintf(stderr, "%s\n", opts->help); + continue; + } + + pos = fprintf(stderr, " "); + if (opts->short_name) + pos += fprintf(stderr, "-%c", opts->short_name); + if (opts->long_name && opts->short_name) + pos += fprintf(stderr, ", "); + if (opts->long_name) + pos += fprintf(stderr, "--%s", opts->long_name); + + switch (opts->type) { + case OPTION_INTEGER: + if (opts->flags & PARSE_OPT_OPTARG) + pos += fprintf(stderr, " [<n>]"); + else + pos += fprintf(stderr, " <n>"); + break; + case OPTION_CALLBACK: + if (opts->flags & PARSE_OPT_NOARG) + break; + /* FALLTHROUGH */ + case OPTION_STRING: + if (opts->argh) { + if (opts->flags & PARSE_OPT_OPTARG) + pos += fprintf(stderr, " [<%s>]", opts->argh); + else + pos += fprintf(stderr, " <%s>", opts->argh); + } else { + if (opts->flags & PARSE_OPT_OPTARG) + pos += fprintf(stderr, " [...]"); + else + pos += fprintf(stderr, " ..."); + } + break; + default: + break; + } + + if (pos <= USAGE_OPTS_WIDTH) + pad = USAGE_OPTS_WIDTH - pos; + else { + fputc('\n', stderr); + pad = USAGE_OPTS_WIDTH; + } + fprintf(stderr, "%*s%s\n", pad + USAGE_GAP, "", opts->help); + } + fputc('\n', stderr); + + exit(129); +} + +/*----- some often used options -----*/ +#include "cache.h" +int parse_opt_abbrev_cb(const struct option *opt, const char *arg, int unset) +{ + int v; + + if (!arg) { + v = unset ? 0 : DEFAULT_ABBREV; + } else { + v = strtol(arg, (char **)&arg, 10); + if (*arg) + return opterror(opt, "expects a numerical value", 0); + if (v && v < MINIMUM_ABBREV) + v = MINIMUM_ABBREV; + else if (v > 40) + v = 40; + } + *(int *)(opt->value) = v; + return 0; +} |