neorados: Do not try to decode an empty response in notify

The response can be empty on some errors. Attempting to decode an
empty one loses the error value on valid errors. Also swallow any
decode errors.

Signed-off-by: Adam C. Emerson <aemerson@redhat.com>

diff --git a/src/neorados/RADOS.cc b/src/neorados/RADOS.cc
index 69d5bc4cd256d25ccd8f54eef9bbaead51242d55..3cd8fcc50b09d218e1c10c7cb01c331e80fa9f2d 100644 (file)
--- a/src/neorados/RADOS.cc
+++ b/src/neorados/RADOS.cc
@@ -1721,11 +1721,16 @@ struct NotifyHandler : std::enable_shared_from_this<NotifyHandler> {
       ceph_assert(c);
       bc::flat_map<std::pair<uint64_t, uint64_t>, buffer::list> reply_map;
       bc::flat_set<std::pair<uint64_t, uint64_t>> missed_set;
-      auto p = rbl.cbegin();
-      decode(reply_map, p);
-      decode(missed_set, p);
-      asio::dispatch(asio::append(std::move(c), res, std::move(reply_map),
-                                 std::move(missed_set)));
+      if (rbl.length() > 0) try {
+          auto p = rbl.cbegin();
+          decode(reply_map, p);
+          decode(missed_set, p);
+      } catch (const std::exception&) {
+        // Swallowing the decode error.
+      }
+      asio::dispatch(
+          asio::append(
+              std::move(c), res, std::move(reply_map), std::move(missed_set)));
     }
   }
 };