Function convert_to_sparse_rec

sparse-index.c:60–130

* Returns the number of entries "inserted" into the index. */

 * Returns the number of entries "inserted" into the index.
 */
static int convert_to_sparse_rec(struct index_state *istate,
				 int num_converted,
				 int start, int end,
				 const char *ct_path, size_t ct_pathlen,
				 struct cache_tree *ct)
{
	int i, can_convert = 1;
	int start_converted = num_converted;
	struct strbuf child_path = STRBUF_INIT;

	/*
	 * Is the current path outside of the sparse cone?
	 * Then check if the region can be replaced by a sparse
	 * directory entry (everything is sparse and merged).
	 */
	if (path_in_sparse_checkout(ct_path, istate))
		can_convert = 0;

	for (i = start; can_convert && i < end; i++) {
		struct cache_entry *ce = istate->cache[i];

		if (ce_stage(ce) ||
		    S_ISGITLINK(ce->ce_mode) ||
		    !(ce->ce_flags & CE_SKIP_WORKTREE))
			can_convert = 0;
	}

	if (can_convert) {
		struct cache_entry *se;
		se = construct_sparse_dir_entry(istate, ct_path, ct);

		istate->cache[num_converted++] = se;
		return 1;
	}

	for (i = start; i < end; ) {
		int count, span, pos = -1;
		const char *base, *slash;
		struct cache_entry *ce = istate->cache[i];

		/*
		 * Detect if this is a normal entry outside of any subtree
		 * entry.
		 */
		base = ce->name + ct_pathlen;
		slash = strchr(base, '/');

		if (slash)
			pos = cache_tree_subtree_pos(ct, base, slash - base);

		if (pos < 0) {
			istate->cache[num_converted++] = ce;
			i++;
			continue;
		}

		strbuf_setlen(&child_path, 0);
		strbuf_add(&child_path, ce->name, slash - ce->name + 1);