diff options
Diffstat (limited to 'tools/optparse.c')
| -rw-r--r-- | tools/optparse.c | 264 |
1 files changed, 264 insertions, 0 deletions
diff --git a/tools/optparse.c b/tools/optparse.c new file mode 100644 index 0000000..4242bff --- /dev/null +++ b/tools/optparse.c @@ -0,0 +1,264 @@ +#include "optparse.h" + +#define MSG_INVALID "invalid option" +#define MSG_MISSING "option requires an argument" +#define MSG_TOOMANY "option takes no arguments" + +static int +opterror(struct optparse *options, const char *message, const char *data) +{ + unsigned p = 0; + while (*message) + options->errmsg[p++] = *message++; + const char *sep = " -- '"; + while (*sep) + options->errmsg[p++] = *sep++; + while (p < sizeof(options->errmsg) - 2 && *data) + options->errmsg[p++] = *data++; + options->errmsg[p++] = '\''; + options->errmsg[p++] = '\0'; + return '?'; +} + +void optparse_init(struct optparse *options, char **argv) +{ + options->argv = argv; + options->permute = 1; + options->optind = 1; + options->subopt = 0; + options->optarg = 0; + options->errmsg[0] = '\0'; +} + +static inline int +is_dashdash(const char *arg) +{ + return arg != 0 && arg[0] == '-' && arg[1] == '-' && arg[2] == '\0'; +} + +static inline int +is_shortopt(const char *arg) +{ + return arg != 0 && arg[0] == '-' && arg[1] != '-' && arg[1] != '\0'; +} + +static inline int +is_longopt(const char *arg) +{ + return arg != 0 && arg[0] == '-' && arg[1] == '-' && arg[2] != '\0'; +} + +static void +permute(struct optparse *options, int index) +{ + char *nonoption = options->argv[index]; + for (int i = index; i < options->optind - 1; i++) + options->argv[i] = options->argv[i + 1]; + options->argv[options->optind - 1] = nonoption; +} + +static int +argtype(const char *optstring, char c) +{ + if (c == ':') + return -1; + for (; *optstring && c != *optstring; optstring++); + if (!*optstring) + return -1; + int count = OPTPARSE_NONE; + if (optstring[1] == ':') + count += optstring[2] == ':' ? 2 : 1; + return count; +} + +int optparse(struct optparse *options, const char *optstring) +{ + options->errmsg[0] = '\0'; + options->optopt = 0; + options->optarg = 0; + char *option = options->argv[options->optind]; + if (option == 0) { + return -1; + } else if (is_dashdash(option)) { + options->optind++; /* consume "--" */ + return -1; + } else if (!is_shortopt(option)) { + if (options->permute) { + int index = options->optind; + options->optind++; + int r = optparse(options, optstring); + permute(options, index); + options->optind--; + return r; + } else { + return -1; + } + } + option += options->subopt + 1; + options->optopt = option[0]; + int type = argtype(optstring, option[0]); + char *next = options->argv[options->optind + 1]; + switch (type) { + case -1: { + options->optind++; + char str[2] = {option[0]}; + return opterror(options, MSG_INVALID, str); + } + case OPTPARSE_NONE: + if (option[1]) { + options->subopt++; + } else { + options->subopt = 0; + options->optind++; + } + return option[0]; + case OPTPARSE_REQUIRED: + options->subopt = 0; + options->optind++; + if (option[1]) { + options->optarg = option + 1; + } else if (next != 0) { + options->optarg = next; + options->optind++; + } else { + options->optarg = 0; + char str[2] = {option[0]}; + return opterror(options, MSG_MISSING, str); + } + return option[0]; + case OPTPARSE_OPTIONAL: + options->subopt = 0; + options->optind++; + if (option[1]) + options->optarg = option + 1; + else + options->optarg = 0; + return option[0]; + } + return 0; +} + +char *optparse_arg(struct optparse *options) +{ + options->subopt = 0; + char *option = options->argv[options->optind]; + if (option != 0) + options->optind++; + return option; +} + +static inline int +longopts_end(const struct optparse_long *longopts, int i) +{ + return !longopts[i].longname && !longopts[i].shortname; +} + +static void +optstring_from_long(const struct optparse_long *longopts, char *optstring) +{ + char *p = optstring; + for (int i = 0; !longopts_end(longopts, i); i++) { + if (longopts[i].shortname) { + *p++ = longopts[i].shortname; + for (int a = 0; a < (int)longopts[i].argtype; a++) + *p++ = ':'; + } + } + *p = '\0'; +} + +/* Unlike strcmp(), handles options containing "=". */ +static int +longopts_match(const char *longname, const char *option) +{ + if (longname == 0) + return 0; + const char *a = option, *n = longname; + for (; *a && *n && *a != '='; a++, n++) + if (*a != *n) + return 0; + return *n == '\0' && (*a == '\0' || *a == '='); +} + +/* Return the part after "=", or NULL. */ +static char * +longopts_arg(char *option) +{ + for (; *option && *option != '='; option++); + if (*option == '=') + return option + 1; + else + return 0; +} + +static int +long_fallback(struct optparse *options, + const struct optparse_long *longopts, + int *longindex) +{ + char optstring[96 * 3 + 1]; /* 96 ASCII printable characters */ + optstring_from_long(longopts, optstring); + int result = optparse(options, optstring); + if (longindex != 0) { + *longindex = -1; + if (result != -1) + for (int i = 0; !longopts_end(longopts, i); i++) + if (longopts[i].shortname == options->optopt) + *longindex = i; + } + return result; +} + +int +optparse_long(struct optparse *options, + const struct optparse_long *longopts, + int *longindex) +{ + char *option = options->argv[options->optind]; + if (option == 0) { + return -1; + } else if (is_dashdash(option)) { + options->optind++; /* consume "--" */ + return -1; + } else if (is_shortopt(option)) { + return long_fallback(options, longopts, longindex); + } else if (!is_longopt(option)) { + if (options->permute) { + int index = options->optind; + options->optind++; + int r = optparse_long(options, longopts, longindex); + permute(options, index); + options->optind--; + return r; + } else { + return -1; + } + } + + /* Parse as long option. */ + options->errmsg[0] = '\0'; + options->optopt = 0; + options->optarg = 0; + option += 2; /* skip "--" */ + options->optind++; + for (int i = 0; !longopts_end(longopts, i); i++) { + const char *name = longopts[i].longname; + if (longopts_match(name, option)) { + if (longindex) + *longindex = i; + options->optopt = longopts[i].shortname; + char *arg = longopts_arg(option); + if (longopts[i].argtype == OPTPARSE_NONE && arg != 0) { + return opterror(options, MSG_TOOMANY, name); + } if (arg != 0) { + options->optarg = arg; + } else if (longopts[i].argtype == OPTPARSE_REQUIRED) { + options->optarg = options->argv[options->optind++]; + if (options->optarg == 0) + return opterror(options, MSG_MISSING, name); + } + return options->optopt; + } + } + return opterror(options, MSG_INVALID, option); +} |