refspec: relocate matching related functions

Move the functions `refspec_find_match()`, `refspec_find_all_matches()`
and `refspec_find_negative_match()` from `remote.c` to `refspec.c`.
These functions focus on matching refspecs, so centralizing them in
`refspec.c` improves code organization by keeping refspec-related logic
in one place.

Signed-off-by: Meet Soni <meetsoni3017@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 123 insertions, 0 deletions

diff --git a/refspec.c b/refspec.c
index b447768304..cab0b0d127 100644
--- a/refspec.c
+++ b/refspec.c
@@ -5,6 +5,7 @@
 #include "gettext.h"
 #include "hash.h"
 #include "hex.h"
+#include "string-list.h"
 #include "strvec.h"
 #include "refs.h"
 #include "refspec.h"
@@ -324,3 +325,125 @@ int refname_matches_negative_refspec_item(const char *refname, struct refspec *r
 	}
 	return 0;
 }
+
+static int refspec_find_negative_match(struct refspec *rs, struct refspec_item *query)
+{
+	int i, matched_negative = 0;
+	int find_src = !query->src;
+	struct string_list reversed = STRING_LIST_INIT_DUP;
+	const char *needle = find_src ? query->dst : query->src;
+
+	/*
+	 * Check whether the queried ref matches any negative refpsec. If so,
+	 * then we should ultimately treat this as not matching the query at
+	 * all.
+	 *
+	 * Note that negative refspecs always match the source, but the query
+	 * item uses the destination. To handle this, we apply pattern
+	 * refspecs in reverse to figure out if the query source matches any
+	 * of the negative refspecs.
+	 *
+	 * The first loop finds and expands all positive refspecs
+	 * matched by the queried ref.
+	 *
+	 * The second loop checks if any of the results of the first loop
+	 * match any negative refspec.
+	 */
+	for (i = 0; i < rs->nr; i++) {
+		struct refspec_item *refspec = &rs->items[i];
+		char *expn_name;
+
+		if (refspec->negative)
+			continue;
+
+		/* Note the reversal of src and dst */
+		if (refspec->pattern) {
+			const char *key = refspec->dst ? refspec->dst : refspec->src;
+			const char *value = refspec->src;
+
+			if (match_name_with_pattern(key, needle, value, &expn_name))
+				string_list_append_nodup(&reversed, expn_name);
+		} else if (refspec->matching) {
+			/* For the special matching refspec, any query should match */
+			string_list_append(&reversed, needle);
+		} else if (!refspec->src) {
+			BUG("refspec->src should not be null here");
+		} else if (!strcmp(needle, refspec->src)) {
+			string_list_append(&reversed, refspec->src);
+		}
+	}
+
+	for (i = 0; !matched_negative && i < reversed.nr; i++) {
+		if (refname_matches_negative_refspec_item(reversed.items[i].string, rs))
+			matched_negative = 1;
+	}
+
+	string_list_clear(&reversed, 0);
+
+	return matched_negative;
+}
+
+void refspec_find_all_matches(struct refspec *rs,
+				    struct refspec_item *query,
+				    struct string_list *results)
+{
+	int i;
+	int find_src = !query->src;
+
+	if (find_src && !query->dst)
+		BUG("refspec_find_all_matches: need either src or dst");
+
+	if (refspec_find_negative_match(rs, query))
+		return;
+
+	for (i = 0; i < rs->nr; i++) {
+		struct refspec_item *refspec = &rs->items[i];
+		const char *key = find_src ? refspec->dst : refspec->src;
+		const char *value = find_src ? refspec->src : refspec->dst;
+		const char *needle = find_src ? query->dst : query->src;
+		char **result = find_src ? &query->src : &query->dst;
+
+		if (!refspec->dst || refspec->negative)
+			continue;
+		if (refspec->pattern) {
+			if (match_name_with_pattern(key, needle, value, result))
+				string_list_append_nodup(results, *result);
+		} else if (!strcmp(needle, key)) {
+			string_list_append(results, value);
+		}
+	}
+}
+
+int refspec_find_match(struct refspec *rs, struct refspec_item *query)
+{
+	int i;
+	int find_src = !query->src;
+	const char *needle = find_src ? query->dst : query->src;
+	char **result = find_src ? &query->src : &query->dst;
+
+	if (find_src && !query->dst)
+		BUG("refspec_find_match: need either src or dst");
+
+	if (refspec_find_negative_match(rs, query))
+		return -1;
+
+	for (i = 0; i < rs->nr; i++) {
+		struct refspec_item *refspec = &rs->items[i];
+		const char *key = find_src ? refspec->dst : refspec->src;
+		const char *value = find_src ? refspec->src : refspec->dst;
+
+		if (!refspec->dst || refspec->negative)
+			continue;
+		if (refspec->pattern) {
+			if (match_name_with_pattern(key, needle, value, result)) {
+				query->force = refspec->force;
+				return 0;
+			}
+		} else if (!strcmp(needle, key)) {
+			*result = xstrdup(value);
+			query->force = refspec->force;
+			return 0;
+		}
+	}
+	return -1;
+}