refs: pass NULL to resolve_ref_unsafe() if hash is not needed

This allows us to get rid of some write-only variables, among them seven
SHA1 buffers.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

6 files changed, 7 insertions, 14 deletions

diff --git a/builtin/commit.c b/builtin/commit.c
index 58f9747c2f..39d5b7f6c7 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -1431,7 +1431,6 @@ static void print_summary(const char *prefix, const struct object_id *oid,
 	struct rev_info rev;
 	struct commit *commit;
 	struct strbuf format = STRBUF_INIT;
-	struct object_id junk_oid;
 	const char *head;
 	struct pretty_print_context pctx = {0};
 	struct strbuf author_ident = STRBUF_INIT;
@@ -1484,7 +1483,7 @@ static void print_summary(const char *prefix, const struct object_id *oid,
 	rev.diffopt.break_opt = 0;
 	diff_setup_done(&rev.diffopt);
 
-	head = resolve_ref_unsafe("HEAD", 0, junk_oid.hash, NULL);
+	head = resolve_ref_unsafe("HEAD", 0, NULL, NULL);
 	if (!strcmp(head, "HEAD"))
 		head = _("detached HEAD");
 	else
diff --git a/builtin/log.c b/builtin/log.c
index f8cccbc964..d81a09051e 100644
--- a/builtin/log.c
+++ b/builtin/log.c
@@ -1660,10 +1660,9 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
 			check_head = 1;
 
 		if (check_head) {
-			struct object_id oid;
 			const char *ref, *v;
 			ref = resolve_ref_unsafe("HEAD", RESOLVE_REF_READING,
-						 oid.hash, NULL);
+						 NULL, NULL);
 			if (ref && skip_prefix(ref, "refs/heads/", &v))
 				branch_name = xstrdup(v);
 			else
diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c
index 52c63ebfdc..65d89078ab 100644
--- a/builtin/receive-pack.c
+++ b/builtin/receive-pack.c
@@ -1207,11 +1207,10 @@ static void check_aliased_update(struct command *cmd, struct string_list *list)
 	const char *dst_name;
 	struct string_list_item *item;
 	struct command *dst_cmd;
-	unsigned char sha1[GIT_MAX_RAWSZ];
 	int flag;
 
 	strbuf_addf(&buf, "%s%s", get_git_namespace(), cmd->ref_name);
-	dst_name = resolve_ref_unsafe(buf.buf, 0, sha1, &flag);
+	dst_name = resolve_ref_unsafe(buf.buf, 0, NULL, &flag);
 	strbuf_release(&buf);
 
 	if (!(flag & REF_ISSYMREF))
diff --git a/builtin/remote.c b/builtin/remote.c
index 33ba739332..4f5cac96b0 100644
--- a/builtin/remote.c
+++ b/builtin/remote.c
@@ -558,14 +558,13 @@ static int read_remote_branches(const char *refname,
 	struct strbuf buf = STRBUF_INIT;
 	struct string_list_item *item;
 	int flag;
-	struct object_id orig_oid;
 	const char *symref;
 
 	strbuf_addf(&buf, "refs/remotes/%s/", rename->old);
 	if (starts_with(refname, buf.buf)) {
 		item = string_list_append(rename->remote_branches, xstrdup(refname));
 		symref = resolve_ref_unsafe(refname, RESOLVE_REF_READING,
-					    orig_oid.hash, &flag);
+					    NULL, &flag);
 		if (flag & REF_ISSYMREF)
 			item->util = xstrdup(symref);
 		else
diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index 818fe74f0a..ea49710893 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -17,9 +17,8 @@
 static char *get_default_remote(void)
 {
 	char *dest = NULL, *ret;
-	unsigned char sha1[20];
 	struct strbuf sb = STRBUF_INIT;
-	const char *refname = resolve_ref_unsafe("HEAD", 0, sha1, NULL);
+	const char *refname = resolve_ref_unsafe("HEAD", 0, NULL, NULL);
 
 	if (!refname)
 		die(_("No such ref: %s"), "HEAD");
@@ -1089,8 +1088,7 @@ static const char *remote_submodule_branch(const char *path)
 		return "master";
 
 	if (!strcmp(branch, ".")) {
-		unsigned char sha1[20];
-		const char *refname = resolve_ref_unsafe("HEAD", 0, sha1, NULL);
+		const char *refname = resolve_ref_unsafe("HEAD", 0, NULL, NULL);
 
 		if (!refname)
 			die(_("No such ref: %s"), "HEAD");
diff --git a/builtin/symbolic-ref.c b/builtin/symbolic-ref.c
index df75cb9d4a..17aabaa679 100644
--- a/builtin/symbolic-ref.c
+++ b/builtin/symbolic-ref.c
@@ -12,9 +12,8 @@ static const char * const git_symbolic_ref_usage[] = {
 
 static int check_symref(const char *HEAD, int quiet, int shorten, int print)
 {
-	unsigned char sha1[20];
 	int flag;
-	const char *refname = resolve_ref_unsafe(HEAD, 0, sha1, &flag);
+	const char *refname = resolve_ref_unsafe(HEAD, 0, NULL, &flag);
 
 	if (!refname)
 		die("No such ref: %s", HEAD);