Am 20.01.24 um 18:55 schrieb Junio C Hamano:
>
> I agree with you that the structure of that loop and the processing
> in it does look confusing.
Here's a small simplification.
--- >8 ---
Subject: [PATCH 2/1] parse-options: simplify positivation handling
We accept the positive version of options whose long name starts with
"no-" and are defined without the flag PARSE_OPT_NONEG. E.g. git clone
has an explicitly defined --no-checkout option and also implicitly
accepts --checkout to override it.
parse_long_opt() handles that by restarting the option matching with the
positive version when it finds that only the current option definition
starts with "no-", but not the user-supplied argument. This code is
located almost at the end of the matching logic.
Avoid the need for a restart by moving the code up. We don't have to
check the positive arg against the negative long_name at all -- the
"no-" prefix of the latter makes a match impossible. Skip it and toggle
OPT_UNSET right away to simplify the control flow.
Signed-off-by: René Scharfe <l.s.r@xxxxxx>
---
Patch formatted with --function-context for easier review.
parse-options.c | 13 ++++++-------
1 file changed, 6 insertions(+), 7 deletions(-)
diff --git a/parse-options.c b/parse-options.c
index 92e96ca6cd..63a99dea6e 100644
--- a/parse-options.c
+++ b/parse-options.c
@@ -353,95 +353,94 @@ static int is_alias(struct parse_opt_ctx_t *ctx,
static enum parse_opt_result parse_long_opt(
struct parse_opt_ctx_t *p, const char *arg,
const struct option *options)
{
const char *arg_end = strchrnul(arg, '=');
const struct option *abbrev_option = NULL, *ambiguous_option = NULL;
enum opt_parsed abbrev_flags = OPT_LONG, ambiguous_flags = OPT_LONG;
int allow_abbrev = !(p->flags & PARSE_OPT_KEEP_UNKNOWN_OPT);
for (; options->type != OPTION_END; options++) {
const char *rest, *long_name = options->long_name;
enum opt_parsed flags = OPT_LONG, opt_flags = OPT_LONG;
if (options->type == OPTION_SUBCOMMAND)
continue;
if (!long_name)
continue;
-again:
+ if (!starts_with(arg, "no-") &&
+ !(options->flags & PARSE_OPT_NONEG) &&
+ skip_prefix(long_name, "no-", &long_name))
+ opt_flags |= OPT_UNSET;
+
if (!skip_prefix(arg, long_name, &rest))
rest = NULL;
if (!rest) {
/* abbreviated? */
if (allow_abbrev &&
!strncmp(long_name, arg, arg_end - arg)) {
is_abbreviated:
if (abbrev_option &&
!is_alias(p, abbrev_option, options)) {
/*
* 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 ^ opt_flags;
continue;
}
/* negation allowed? */
if (options->flags & PARSE_OPT_NONEG)
continue;
/* negated and abbreviated very much? */
if (allow_abbrev && starts_with("no-", arg)) {
flags |= OPT_UNSET;
goto is_abbreviated;
}
/* negated? */
- if (!starts_with(arg, "no-")) {
- if (skip_prefix(long_name, "no-", &long_name)) {
- opt_flags |= OPT_UNSET;
- goto again;
- }
+ if (!starts_with(arg, "no-"))
continue;
- }
flags |= OPT_UNSET;
if (!skip_prefix(arg + 3, long_name, &rest)) {
/* abbreviated and negated? */
if (allow_abbrev &&
starts_with(long_name, arg + 3))
goto is_abbreviated;
else
continue;
}
}
if (*rest) {
if (*rest != '=')
continue;
p->opt = rest + 1;
}
return get_value(p, options, flags ^ opt_flags);
}
if (disallow_abbreviated_options && (ambiguous_option || abbrev_option))
die("disallowed abbreviated or ambiguous option '%.*s'",
(int)(arg_end - arg), arg);
if (ambiguous_option) {
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);
return PARSE_OPT_HELP;
}
if (abbrev_option)
return get_value(p, abbrev_option, abbrev_flags);
return PARSE_OPT_UNKNOWN;
}
--
2.43.0
