+static int verify_uptodate_sparse(struct cache_entry *ce, struct unpack_trees_options *o);
+static int verify_absent_sparse(struct cache_entry *ce, const char *action, struct unpack_trees_options *o);
+
+static int will_have_skip_worktree(const struct cache_entry *ce, struct unpack_trees_options *o)
+{
+ const char *basename;
+
+ if (ce_stage(ce))
+ return 0;
+
+ basename = strrchr(ce->name, '/');
+ basename = basename ? basename+1 : ce->name;
+ return excluded_from_list(ce->name, ce_namelen(ce), basename, NULL, o->el) <= 0;
+}
+
+static int apply_sparse_checkout(struct cache_entry *ce, struct unpack_trees_options *o)
+{
+ int was_skip_worktree = ce_skip_worktree(ce);
+
+ if (will_have_skip_worktree(ce, o))
+ ce->ce_flags |= CE_SKIP_WORKTREE;
+ else
+ ce->ce_flags &= ~CE_SKIP_WORKTREE;
+
+ /*
+ * We only care about files getting into the checkout area
+ * If merge strategies want to remove some, go ahead, this
+ * flag will be removed eventually in unpack_trees() if it's
+ * outside checkout area.
+ */
+ if (ce->ce_flags & CE_REMOVE)
+ return 0;
+
+ if (!was_skip_worktree && ce_skip_worktree(ce)) {
+ /*
+ * If CE_UPDATE is set, verify_uptodate() must be called already
+ * also stat info may have lost after merged_entry() so calling
+ * verify_uptodate() again may fail
+ */
+ if (!(ce->ce_flags & CE_UPDATE) && verify_uptodate_sparse(ce, o))
+ return -1;
+ ce->ce_flags |= CE_WT_REMOVE;
+ }
+ if (was_skip_worktree && !ce_skip_worktree(ce)) {
+ if (verify_absent_sparse(ce, "overwritten", o))
+ return -1;
+ ce->ce_flags |= CE_UPDATE;
+ }
+ return 0;
+}
+