[RFC PATCH v2 1/3] ref filter: add multiple-option parsing functions

Kousik Sanagavarapu
2023-07-14T19:43:21Z

The functions

match_placeholder_arg_value()
match_placeholder_bool_arg()

were added in pretty (4f732e0fd7 (pretty: allow %(trailers) options
with explicit value, 2019-01-29)) to parse multiple options in an
argument to --pretty. For example,

git log --pretty="%(trailers:key=Signed-Off-By,separator=%x2C )"

will output all the trailers matching the key and seperates them by
commas per commit.

Add similar functions,

match_atom_arg_value()
match_atom_bool_arg()

in ref-filter. A particular use of this can be seen in the subsequent
commit where we parse the options given to a new atom "describe".

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Hariom Verma <hariom18599@gmail.com>
Signed-off-by: Kousik Sanagavarapu <five231003@gmail.com>
---
ref-filter.c | 59 ++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 59 insertions(+)

diff --git a/ref-filter.c b/ref-filter.c
index e0d03a9f8e..b170994d9d 100644
--- a/ref-filter.c
+++ b/ref-filter.c
@@ -251,6 +251,65 @@ static int err_bad_arg(struct strbuf *sb, const char *name, const char *arg)
return -1;
}

+static int match_atom_arg_value(const char *to_parse, const char *candidate,
+ const char **end, const char **valuestart,
+ size_t *valuelen)
+{
+ const char *atom;
+
+ if (!(skip_prefix(to_parse, candidate, &atom)))
+ return 0;
+ if (valuestart) {
+ if (*atom == '=') {
+ *valuestart = atom + 1;
+ *valuelen = strcspn(*valuestart, ",\0");
+ atom = *valuestart + *valuelen;
+ } else {
+ if (*atom != ',' && *atom != '\0')
+ return 0;
+ *valuestart = NULL;
+ *valuelen = 0;
+ }
+ }
+ if (*atom == ',') {
+ *end = atom + 1;
+ return 1;
+ }
+ if (*atom == '\0') {
+ *end = atom;
+ return 1;
+ }
+ return 0;
+}
+
+static int match_atom_bool_arg(const char *to_parse, const char *candidate,
+ const char **end, int *val)
+{
+ const char *argval;
+ char *strval;
+ size_t arglen;
+ int v;
+
+ if (!match_atom_arg_value(to_parse, candidate, end, &argval, &arglen))
+ return 0;
+
+ if (!argval) {
+ *val = 1;
+ return 1;
+ }
+
+ strval = xstrndup(argval, arglen);
+ v = git_parse_maybe_bool(strval);
+ free(strval);
+
+ if (v == -1)
+ return 0;
+
+ *val = v;
+
+ return 1;
+}
+
static int color_atom_parser(struct ref_format *format, struct used_atom *atom,
const char *color_value, struct strbuf *err)
{
--
2.41.0.321.g26b82700c0.dirty