diff options
| -rw-r--r-- | README | 2 | ||||
| -rw-r--r-- | include/optparse.h | 32 | ||||
| -rw-r--r-- | lib/optparse/optparse.c | 156 |
3 files changed, 189 insertions, 1 deletions
@@ -16,9 +16,9 @@ The headers as of now are: • errors.h — err.h-inspired diagnostics functions • macros.h — miscellaneous utility macros (MIN/MAX/lengthof/etc.) • mbstring.h — multibyte-strings + • optparse.h — option parsing functions • rune.h — inttypes.h but for runes The headers planned for inclusion are: - • optparse.h — option parsing functions • unicode/gbrk.h — grapheme breaking • unicode/props.h — unicode character properties diff --git a/include/optparse.h b/include/optparse.h new file mode 100644 index 0000000..816b192 --- /dev/null +++ b/include/optparse.h @@ -0,0 +1,32 @@ +#ifndef MLIB_OPTPARSE_H +#define MLIB_OPTPARSE_H + +#include <stddef.h> + +#include "__charN_t.h" +#include "__rune.h" +#include "__u8view.h" + +struct optparse { + int optind, subopt; + char errmsg[128]; + char **argv; + struct u8view optarg; +}; + +enum op_argkind { + OPT_NONE, + OPT_OPT, + OPT_REQ, +}; + +struct op_option { + rune shortopt; + const char8_t *longopt; + enum op_argkind argtype; +}; + +rune optparse(struct optparse *, const struct op_option *, size_t); +void optparse_init(struct optparse *, char **); + +#endif /* !MLIB_OPTPARSE_H */ diff --git a/lib/optparse/optparse.c b/lib/optparse/optparse.c new file mode 100644 index 0000000..eaacc52 --- /dev/null +++ b/lib/optparse/optparse.c @@ -0,0 +1,156 @@ +#include <stdio.h> +#include <string.h> + +#include "macros.h" +#include "mbstring.h" +#include "optparse.h" + +#define OPT_MSG_INVALID "invalid option" +#define OPT_MSG_MISSING "option requires an argument" +#define OPT_MSG_TOOMANY "option takes no arguments" + +#define IS_SHORTOPT(s) ((s)[0] == '-' && (s)[1] != '-' && (s)[1] != '\0') +#define IS_LONGOPT(s) ((s)[0] == '-' && (s)[1] == '-' && (s)[2] != '\0') + +#define error(st, msg, x) \ + _Generic((x), const char *: error_s, rune: error_r)((st), (msg), (x)) + +static bool is_a_match(const char *, const char *); +static rune error_r(struct optparse *, const char *, rune); +static rune error_s(struct optparse *, const char *, const char *); +static rune shortopt(struct optparse *, const struct op_option *, size_t); + +void +optparse_init(struct optparse *st, char **argv) +{ + st->argv = argv; + st->optind = argv[0] != nullptr; + st->subopt = 0; + st->optarg = (struct u8view){}; + st->errmsg[0] = '\0'; +} + +rune +optparse(struct optparse *st, const struct op_option *opts, size_t nopts) +{ + st->errmsg[0] = '\0'; + st->optarg = (struct u8view){}; + + const char *opt = st->argv[st->optind]; + if (opt == nullptr) + return 0; + if (streq(opt, "--")) { + st->optind++; + return 0; + } + if (IS_SHORTOPT(opt)) + return shortopt(st, opts, nopts); + if (!IS_LONGOPT(opt)) + return 0; + + st->subopt = 0; + st->optind++; + opt += 2; /* Skip ‘--’ */ + + for (size_t i = 0; i < nopts; i++) { + struct op_option o = opts[i]; + if (!is_a_match(opt, o.longopt)) + continue; + switch (o.argtype) { + case OPT_NONE: + if (strchr(opt, '=') != nullptr) + return error(st, OPT_MSG_TOOMANY, opt); + break; + case OPT_REQ: { + const char *p = strchr(opt, '='); + if (p == nullptr) { + if (st->argv[st->optind] == nullptr) + return error(st, OPT_MSG_MISSING, opt); + st->optarg.p = st->argv[st->optind++]; + } else + st->optarg.p = p + 1; + st->optarg.len = strlen(st->optarg.p); + } break; + case OPT_OPT: { + const char *p = strchr(opt, '='); + if (p == nullptr) + st->optarg = (struct u8view){}; + else { + st->optarg.p = p + 1; + st->optarg.len = strlen(st->optarg.p); + } + } break; + } + return o.shortopt; + } + + return error(st, OPT_MSG_INVALID, opt); +} + +rune +shortopt(struct optparse *st, const struct op_option *opts, size_t nopts) +{ + rune ch; + const char *opt = st->argv[st->optind]; + st->subopt += u8tor(&ch, opt + st->subopt + 1); + if (ch == '\0') { + st->subopt = 0; + st->optind++; + return optparse(st, opts, nopts); + } + for (size_t i = 0; i < nopts; i++) { + if (opts[i].shortopt != ch) + continue; + if (opts[i].argtype == OPT_NONE) + goto out; + if (opt[st->subopt + 1] != '\0') { + st->optarg.p = opt + st->subopt + 1; + st->optarg.len = strlen(st->optarg.p); + st->subopt = 0; + st->optind++; + goto out; + } + if (opts[i].argtype == OPT_OPT) { + st->optarg = (struct u8view){}; + goto out; + } + if (st->argv[st->optind + 1] == nullptr) { + st->optarg = (struct u8view){}; + return error(st, OPT_MSG_MISSING, ch); + } + st->optarg.p = st->argv[st->optind + 1]; + st->optarg.len = strlen(st->optarg.p); + st->optind += 2; + goto out; + } + return error(st, OPT_MSG_INVALID, ch); +out: + return ch; +} + +bool +is_a_match(const char *u, const char *t) +{ + for (; *u && *t && *u != '='; u++, t++) { + if (*u != *t) + return false; + } + return *t == '\0' && (*u == '\0' || *u == '='); +} + +rune +error_s(struct optparse *st, const char *msg, const char *s) +{ + const char *p = strchr(s, '='); + snprintf(st->errmsg, sizeof(st->errmsg), u8"%s — ‘%.*s’", msg, + (int)(p ? p - s : strlen(s)), s); + return -1; +} + +rune +error_r(struct optparse *st, const char *msg, rune ch) +{ + char buf[U8_LEN_MAX + 1] = {}; + rtou8(buf, ch, sizeof(buf)); + return error_s(st, msg, buf); +} |