Re: [PATCH] remote.c: Fix overtight refspec validation

From: Daniel Barkalow <barkalow@iabervon.org>
Date: Mar 26, 2008, 05:42 UTC
Message-ID: <alpine.LNX.1.00.0803260130390.19665@iabervon.org>
In-Reply-To: <7vfxuejf9d.fsf@gitster.siamese.dyndns.org>

On Tue, 25 Mar 2008, Junio C Hamano wrote:

Show 10 quoted lines

> This however has unintended side effect of allowing 
> 
> 	[remote "bour"]
>         	url = ../neighbour
>                 fetch = refs/heads/*
> 
> at the syntax level.  I do not know offhand the fetch backends are
> prepared to deal with such wildcard patterns.
> 
> Daniel?

It's not a matter of the backends, which don't implement any of the control flow in the fetch direction; it's get_expanded_map(), which needs to be told that you can have something match a pattern but not have a local tracking ref.

OTOH, the only use for such a pattern is an octopus merge of whatever branches a remote happens to have, right? I remember thinking this was a non-useful refspec when I was dealing with the fetch code (and then forgetting that it was useful for push). It might be better to just disallow it in the direction-specific semantic checks.

Here's the patch to make it work, anyway: ----

commit 6a8bcb917e1aa9b3c972f14f618ab573e457ebee
Author: Daniel Barkalow <barkalow@iabervon.org>
Date:   Wed Mar 26 01:39:07 2008 -0400

    Support fetching refspecs like "refs/heads/*"
    
    Signed-off-by: Daniel Barkalow <barkalow@iabervon.org>

diff --git a/remote.c b/remote.c
index a027bca..f8f4b34 100644
--- a/remote.c
+++ b/remote.c
@@ -998,22 +998,24 @@ static struct ref *get_expanded_map(const struct ref *remote_refs,
 	struct ref **tail = &ret;
 
 	int remote_prefix_len = strlen(refspec->src);
-	int local_prefix_len = strlen(refspec->dst);
+	int local_prefix_len = refspec->dst ? strlen(refspec->dst) : 0;
 
 	for (ref = remote_refs; ref; ref = ref->next) {
 		if (strchr(ref->name, '^'))
 			continue; /* a dereference item */
 		if (!prefixcmp(ref->name, refspec->src)) {
-			const char *match;
 			struct ref *cpy = copy_ref(ref);
-			match = ref->name + remote_prefix_len;
-
-			cpy->peer_ref = alloc_ref(local_prefix_len +
-						  strlen(match) + 1);
-			sprintf(cpy->peer_ref->name, "%s%s",
-				refspec->dst, match);
-			if (refspec->force)
-				cpy->peer_ref->force = 1;
+
+			if (refspec->dst) {
+				const char *match = ref->name + 
+					remote_prefix_len;
+				cpy->peer_ref = alloc_ref(local_prefix_len +
+							  strlen(match) + 1);
+				sprintf(cpy->peer_ref->name, "%s%s",
+					refspec->dst, match);
+				if (refspec->force)
+					cpy->peer_ref->force = 1;
+			}
 			*tail = cpy;
 			tail = &cpy->next;
 		}