Re: [PATCH 2/5] support fetching into a shallow repository

> Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:
> 
> > diff --git a/shallow.c b/shallow.c
> > new file mode 100644
> > index 0000000..3cf2127
> > --- /dev/null
> > +++ b/shallow.c
> >...
> > +struct commit_list *get_shallow_commits(struct object_array *heads, int depth)
> > +{
> > +	int i = 0, cur_depth = 0;
> > +	struct commit_list *result = NULL;
> > +	struct object_array stack = {0, 0, NULL};
> > +	struct commit *commit = NULL;
> > +
> > +	while (commit || i < heads->nr || stack.nr) {
> > +		struct commit_list *p;
> > +		if (!commit) {
> >...
> > +		}
> > +		parse_commit(commit);
> > +		cur_depth++;
> > +		for (p = commit->parents, commit = NULL; p; p = p->next) {
> > +			if (!p->item->util) {
> >...
> > +			} else {
> >...
> > +			}
> > +			if (cur_depth < depth) {
> > +				if (p->next)
> > +					add_object_array(&p->item->object,
> > +							NULL, &stack);
> > +				else {
> > +					commit = p->item;
> > +					cur_depth = *(int *)commit->util;
> > +				}
> > +			} else
> > +				commit_list_insert(p->item, &result);
> > +		}
> > +	}
> > +
> > +	return result;
> > +}
> 
> I think the "commit = p->item" part is trying to do a tail
> recursion optimization, but this is a bit too clever to my
> liking (at first I mistook that the code forgot to re-point p at
> its parents list and incrementing cur_depth).