Re: [PATCH v3 2/8] Add delta-islands.{c,h}

> diff --git a/delta-islands.c b/delta-islands.c
> new file mode 100644
> index 0000000000..448ddcbbe4
> --- /dev/null
> +++ b/delta-islands.c

> +static void deduplicate_islands(void)
> +{
> +	struct remote_island *island, *core = NULL, **list;
> +	unsigned int island_count, dst, src, ref, i = 0;
> +
> +	island_count = kh_size(remote_islands);
> +	list = xmalloc(island_count * sizeof(struct remote_island *));

> +
> +	kh_foreach_value(remote_islands, island, {
> +		list[i++] = island;
> +	});
> +
> +	for (ref = 0; ref + 1 < island_count; ref++) {
> +		for (src = ref + 1, dst = src; src < island_count; src++) {
> +			if (list[ref]->hash == list[src]->hash)
> +				continue;
> +
> +			if (src != dst)
> +				list[dst] = list[src];
> +
> +			dst++;
> +		}
> +		island_count = dst;
> +	}
> +
> +	island_bitmap_size = (island_count / 32) + 1;
> +	core = get_core_island();
> +
> +	for (i = 0; i < island_count; ++i) {
> +		mark_remote_island_1(list[i], core && list[i]->hash == core->hash);
> +	}
> +
> +	free(list);
> +}