move locate_head() to remote.c

Move locate_head() to remote.c and rename it to guess_remote_head() to
more accurately reflect what it does. This is in preparation for being
able to call it from builtin-remote.c
Signed-off-by: NJay Soffian <jaysoffian@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

builtin-clone.c

@@ -20,6 +20,7 @@
 #include "dir.h"
 #include "pack-refs.h"
 #include "sigchain.h"
+#include "remote.h"
 
 /*
  * Overall FIXMEs:
@@ -293,43 +294,6 @@ static void remove_junk_on_signal(int signo)
 	raise(signo);
 }
 
-static const struct ref *locate_head(const struct ref *refs,
-				     const struct ref *mapped_refs,
-				     const struct ref **remote_head_p)
-{
-	const struct ref *remote_head = NULL;
-	const struct ref *remote_master = NULL;
-	const struct ref *r;
-	for (r = refs; r; r = r->next)
-		if (!strcmp(r->name, "HEAD"))
-			remote_head = r;
-
-	for (r = mapped_refs; r; r = r->next)
-		if (!strcmp(r->name, "refs/heads/master"))
-			remote_master = r;
-
-	if (remote_head_p)
-		*remote_head_p = remote_head;
-
-	/* If there's no HEAD value at all, never mind. */
-	if (!remote_head)
-		return NULL;
-
-	/* If refs/heads/master could be right, it is. */
-	if (remote_master && !hashcmp(remote_master->old_sha1,
-				      remote_head->old_sha1))
-		return remote_master;
-
-	/* Look for another ref that points there */
-	for (r = mapped_refs; r; r = r->next)
-		if (r != remote_head &&
-		    !hashcmp(r->old_sha1, remote_head->old_sha1))
-			return r;
-
-	/* Nothing is the same */
-	return NULL;
-}
-
 static struct ref *write_remote_refs(const struct ref *refs,
 		struct refspec *refspec, const char *reflog)
 {
@@ -545,7 +509,8 @@ int cmd_clone(int argc, const char **argv, const char *prefix)
 
 		mapped_refs = write_remote_refs(refs, &refspec, reflog_msg.buf);
 
-		head_points_at = locate_head(refs, mapped_refs, &remote_head);
+		head_points_at = guess_remote_head(refs, mapped_refs,
+						   &remote_head);
 	}
 	else {
 		warning("You appear to have cloned an empty repository.");

remote.c

@@ -1451,3 +1451,40 @@ struct ref *get_local_heads(void)
 	for_each_ref(one_local_ref, &local_tail);
 	return local_refs;
 }
+
+const struct ref *guess_remote_head(const struct ref *refs,
+				    const struct ref *mapped_refs,
+				    const struct ref **remote_head_p)
+{
+	const struct ref *remote_head = NULL;
+	const struct ref *remote_master = NULL;
+	const struct ref *r;
+	for (r = refs; r; r = r->next)
+		if (!strcmp(r->name, "HEAD"))
+			remote_head = r;
+
+	for (r = mapped_refs; r; r = r->next)
+		if (!strcmp(r->name, "refs/heads/master"))
+			remote_master = r;
+
+	if (remote_head_p)
+		*remote_head_p = remote_head;
+
+	/* If there's no HEAD value at all, never mind. */
+	if (!remote_head)
+		return NULL;
+
+	/* If refs/heads/master could be right, it is. */
+	if (remote_master && !hashcmp(remote_master->old_sha1,
+				      remote_head->old_sha1))
+		return remote_master;
+
+	/* Look for another ref that points there */
+	for (r = mapped_refs; r; r = r->next)
+		if (r != remote_head &&
+		    !hashcmp(r->old_sha1, remote_head->old_sha1))
+			return r;
+
+	/* Nothing is the same */
+	return NULL;
+}

remote.h

@@ -139,4 +139,13 @@ int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs);
 int format_tracking_info(struct branch *branch, struct strbuf *sb);
 
 struct ref *get_local_heads(void);
+/*
+ * Look in refs for HEAD. Then look for a matching SHA1 in mapped_refs,
+ * first checking if refs/heads/master matches. Return NULL if nothing matches
+ * or if there is no HEAD in refs. remote_head_p is assigned HEAD if not NULL.
+ */
+const struct ref *guess_remote_head(const struct ref *refs,
+				    const struct ref *mapped_refs,
+				    const struct ref **remote_head_p);
+
 #endif