[PATCH] Introduce get_octopus_merge_bases() in commit.c

[Miklos Vajna <vmiklos@frugalware.org>]

This is like get_merge_bases() but it works for multiple heads.
Internally it uses merge_bases_many() but it has the ability to clear
commit marks like get_merge_bases().

Signed-off-by: Miklos Vajna <vmiklos@frugalware.org>
---

On Thu, Jun 05, 2008 at 10:53:59PM -0700, Junio C Hamano <gitster@pobox.com> wrote:
> Something like this might be enough to get us started.  Instead of
> finding
> out the merge bases between two commits, "one" and "two", this would
> find
> merge base between "one" and a commit that would be a merge across all
> the
> "two"s.  To apply it to the above example, you would give "C" as
> "one",
> and "A" and "B" as "twos" to it, to compute "2".

Here is what I pushed to my working branch, on top of your patch.

BTW: How should I credit your patch? Add a Signed-off-by? If I make you
the author I don't know how send-email handles the situation.

Thanks.

 commit.c |   17 +++++++++++++++++
 commit.h |    1 +
 2 files changed, 18 insertions(+), 0 deletions(-)

diff --git a/commit.c b/commit.c
index 1dba717..685a144 100644
--- a/commit.c
+++ b/commit.c
@@ -618,6 +618,23 @@ static struct commit_list *merge_bases(struct commit *one, struct commit *two)
 	return merge_bases_many(one, 1, &two);
 }
 
+struct commit_list *get_octopus_merge_bases(struct commit_list *in, int cleanup)
+{
+	struct commit *head = in->item;
+	int n = 0;
+	struct commit **commits = xmalloc(n*sizeof(struct commit *));
+	struct commit_list *ret, *i;
+
+	for(i = in; i; i = i->next, n++)
+		commits[n] = i->item;
+	ret = merge_bases_many(head, n, commits);
+	free(commits);
+	if (cleanup)
+		for(i = in; i; i = i->next)
+			clear_commit_marks(i->item, all_flags);
+	return ret;
+}
+
 struct commit_list *get_merge_bases(struct commit *one,
 					struct commit *two, int cleanup)
 {
diff --git a/commit.h b/commit.h
index 7f8c5ee..ca858ed 100644
--- a/commit.h
+++ b/commit.h
@@ -121,6 +121,7 @@ int read_graft_file(const char *graft_file);
 struct commit_graft *lookup_commit_graft(const unsigned char *sha1);
 
 extern struct commit_list *get_merge_bases(struct commit *rev1, struct commit *rev2, int cleanup);
+extern struct commit_list *get_octopus_merge_bases(struct commit_list *in, int cleanup);
 
 extern int register_shallow(const unsigned char *sha1);
 extern int unregister_shallow(const unsigned char *sha1);
-- 
1.5.6.rc0.dirty