repack_without_refs(): make the refnames argument a string_list

Most of the callers have string_lists available already, whereas two
of them had to read data out of a string_list into an array of strings
just to call this function. So change repack_without_refs() to take
the list of refnames to omit as a string_list, and change the callers
accordingly.

Suggested-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/remote.c

@@ -750,16 +750,11 @@ static int mv(int argc, const char **argv)
 static int remove_branches(struct string_list *branches)
 {
 	struct strbuf err = STRBUF_INIT;
-	const char **branch_names;
 	int i, result = 0;
 
-	branch_names = xmalloc(branches->nr * sizeof(*branch_names));
+	if (repack_without_refs(branches, &err))
-	for (i = 0; i < branches->nr; i++)
-		branch_names[i] = branches->items[i].string;
-	if (repack_without_refs(branch_names, branches->nr, &err))
 		result |= error("%s", err.buf);
 	strbuf_release(&err);
-	free(branch_names);
 
 	for (i = 0; i < branches->nr; i++) {
 		struct string_list_item *item = branches->items + i;
@@ -1317,7 +1312,6 @@ static int prune_remote(const char *remote, int dry_run)
 	int result = 0, i;
 	struct ref_states states;
 	struct string_list delete_refs_list = STRING_LIST_INIT_NODUP;
-	const char **delete_refs;
 	const char *dangling_msg = dry_run
 		? _(" %s will become dangling!")
 		: _(" %s has become dangling!");
@@ -1336,19 +1330,16 @@ static int prune_remote(const char *remote, int dry_run)
 		  ? states.remote->url[0]
 		  : _("(no URL)"));
 
-	delete_refs = xmalloc(states.stale.nr * sizeof(*delete_refs));
 	for (i = 0; i < states.stale.nr; i++) {
 		const char *refname = states.stale.items[i].util;
 
-		delete_refs[i] = refname;
 		string_list_append(&delete_refs_list, refname);
 	}
 	sort_string_list(&delete_refs_list);
 
 	if (!dry_run) {
 		struct strbuf err = STRBUF_INIT;
-		if (repack_without_refs(delete_refs, states.stale.nr,
+		if (repack_without_refs(&delete_refs_list, &err))
-					&err))
 			result |= error("%s", err.buf);
 		strbuf_release(&err);
 	}
@@ -1369,7 +1360,6 @@ static int prune_remote(const char *remote, int dry_run)
 
 	warn_dangling_symrefs(stdout, dangling_msg, &delete_refs_list);
 
-	free(delete_refs);
 	string_list_clear(&delete_refs_list, 0);
 	free_remote_ref_states(&states);
 	return result;

refs.c

@@ -2639,22 +2639,25 @@ static int curate_packed_ref_fn(struct ref_entry *entry, void *cb_data)
 	return 0;
 }
 
-int repack_without_refs(const char **refnames, int n, struct strbuf *err)
+int repack_without_refs(struct string_list *refnames, struct strbuf *err)
 {
 	struct ref_dir *packed;
 	struct string_list refs_to_delete = STRING_LIST_INIT_DUP;
-	struct string_list_item *ref_to_delete;
+	struct string_list_item *refname, *ref_to_delete;
-	int i, ret, removed = 0;
+	int ret, needs_repacking = 0, removed = 0;
 
 	assert(err);
 
 	/* Look for a packed ref */
-	for (i = 0; i < n; i++)
+	for_each_string_list_item(refname, refnames) {
-		if (get_packed_ref(refnames[i]))
+		if (get_packed_ref(refname->string)) {
+			needs_repacking = 1;
 			break;
+		}
+	}
 
 	/* Avoid locking if we have nothing to do */
-	if (i == n)
+	if (!needs_repacking)
 		return 0; /* no refname exists in packed refs */
 
 	if (lock_packed_refs(0)) {
@@ -2664,8 +2667,8 @@ int repack_without_refs(const char **refnames, int n, struct strbuf *err)
 	packed = get_packed_refs(&ref_cache);
 
 	/* Remove refnames from the cache */
-	for (i = 0; i < n; i++)
+	for_each_string_list_item(refname, refnames)
-		if (remove_entry(packed, refnames[i]) != -1)
+		if (remove_entry(packed, refname->string) != -1)
 			removed = 1;
 	if (!removed) {
 		/*
@@ -3738,10 +3741,11 @@ static int ref_update_reject_duplicates(struct ref_update **updates, int n,
 int ref_transaction_commit(struct ref_transaction *transaction,
 			   struct strbuf *err)
 {
-	int ret = 0, delnum = 0, i;
+	int ret = 0, i;
-	const char **delnames;
 	int n = transaction->nr;
 	struct ref_update **updates = transaction->updates;
+	struct string_list refs_to_delete = STRING_LIST_INIT_NODUP;
+	struct string_list_item *ref_to_delete;
 
 	assert(err);
 
@@ -3753,9 +3757,6 @@ int ref_transaction_commit(struct ref_transaction *transaction,
 		return 0;
 	}
 
-	/* Allocate work space */
-	delnames = xmalloc(sizeof(*delnames) * n);
-
 	/* Copy, sort, and reject duplicate refs */
 	qsort(updates, n, sizeof(*updates), ref_update_compare);
 	if (ref_update_reject_duplicates(updates, n, err)) {
@@ -3815,16 +3816,17 @@ int ref_transaction_commit(struct ref_transaction *transaction,
 			}
 
 			if (!(update->flags & REF_ISPRUNING))
-				delnames[delnum++] = update->lock->ref_name;
+				string_list_append(&refs_to_delete,
+						   update->lock->ref_name);
 		}
 	}
 
-	if (repack_without_refs(delnames, delnum, err)) {
+	if (repack_without_refs(&refs_to_delete, err)) {
 		ret = TRANSACTION_GENERIC_ERROR;
 		goto cleanup;
 	}
-	for (i = 0; i < delnum; i++)
+	for_each_string_list_item(ref_to_delete, &refs_to_delete)
-		unlink_or_warn(git_path("logs/%s", delnames[i]));
+		unlink_or_warn(git_path("logs/%s", ref_to_delete->string));
 	clear_loose_ref_cache(&ref_cache);
 
 cleanup:
@@ -3833,7 +3835,7 @@ cleanup:
 	for (i = 0; i < n; i++)
 		if (updates[i]->lock)
 			unlock_ref(updates[i]->lock);
-	free(delnames);
+	string_list_clear(&refs_to_delete, 0);
 	return ret;
 }
 

refs.h

@@ -163,7 +163,15 @@ extern void rollback_packed_refs(void);
  */
 int pack_refs(unsigned int flags);
 
-extern int repack_without_refs(const char **refnames, int n,
+/*
+ * Rewrite the packed-refs file, omitting any refs listed in
+ * 'refnames'. On error, packed-refs will be unchanged, the return
+ * value is nonzero, and a message about the error is written to the
+ * 'err' strbuf.
+ *
+ * The refs in 'refnames' needn't be sorted. `err` must not be NULL.
+ */
+extern int repack_without_refs(struct string_list *refnames,
 			       struct strbuf *err);
 
 extern int ref_exists(const char *);