lib: avoid set size check when generating diff datum from json

Added ovsdb_transient_datum_from_json() to avoid size check for
the diff datum that is transient in nature.
Suppose a datum contains set, and the max number of elements is 2.
If we are changing from set that contains [A, B], to a set contains
[C, D], the diff datum will contains 4 elements [A, B, C, D].

Thus diff datum should not be constrained by the size limit. However
the datum after diff is applied should not violate the size limit.

Signed-off-by: Andy Zhou <azhou@nicira.com>
Acked-by: Ben Pfaff <blp@ovn.org>

1 files changed, 5 insertions, 0 deletions

diff --git a/lib/ovsdb-data.h b/lib/ovsdb-data.h
index e144c70d0..802f7184c 100644
--- a/lib/ovsdb-data.h
+++ b/lib/ovsdb-data.h
@@ -161,6 +161,11 @@ struct ovsdb_error *ovsdb_datum_from_json(struct ovsdb_datum *,
                                           const struct json *,
                                           struct ovsdb_symbol_table *)
     OVS_WARN_UNUSED_RESULT;
+struct ovsdb_error *ovsdb_transient_datum_from_json(
+                                          struct ovsdb_datum *,
+                                          const struct ovsdb_type *,
+                                          const struct json *)
+    OVS_WARN_UNUSED_RESULT;
 struct json *ovsdb_datum_to_json(const struct ovsdb_datum *,
                                  const struct ovsdb_type *);