[PATCH 1/4] Do not try to process objects more than once during fetch

[Sergey Vlasov <vsu@altlinux.ru>]

fetch.c:process() is often called more than once for the same object;
e.g., for unpacked git repository with 7313 objects there are 320997
calls to process() for objects which were already seen (and 7528 of
those calls are for tree objects, which is a real problem because of
recursive processing).

---

 fetch.c |    8 ++++++++
 1 files changed, 8 insertions(+), 0 deletions(-)

f8285569e916a21c28379b55415165a89794272a
diff --git a/fetch.c b/fetch.c
--- a/fetch.c
+++ b/fetch.c
@@ -7,6 +7,8 @@
 #include "blob.h"
 #include "refs.h"
 
+#define SEEN		(1u << 0)
+
 const char *write_ref = NULL;
 
 const unsigned char *current_ref = NULL;
@@ -126,6 +128,12 @@ static int process_object(struct object 
 static int process(unsigned char *sha1, const char *type)
 {
 	struct object *obj = lookup_object_type(sha1, type);
+
+	/* Do not try to process objects more than once */
+	if (obj->flags & SEEN)
+		return 0;
+	obj->flags |= SEEN;
+
 	if (has_sha1_file(sha1)) {
 		parse_object(sha1);
 		/* We already have it, so we should scan it now. */