use only ready peers as sync source

Sync messages now carries a ready flag, telling whether the sending peer
itself is joined or is itself still (re-)joining.  In the latter case,
the peer won't be used as sync source.

1 files changed, 4 insertions, 0 deletions

diff --git a/src/state.rs b/src/state.rs
index 4fbc05b..23892a9 100644
--- a/src/state.rs
+++ b/src/state.rs
@@ -120,6 +120,9 @@ pub(crate) struct PeerState {
 
     /// Epoch the peer advertised in its most recent message.
     pub(crate) epoch: Option<Epoch>,
+
+    /// Whether the peer was ready according to its most recent sync message.
+    pub(crate) reports_ready: Option<bool>,
 }
 
 /// One Automerge sync with a peer, from a reset to the next. Everything a reset must
@@ -322,6 +325,7 @@ impl PeerState {
             last_sync_rx: None,
             last_resync_at: None,
             epoch: None,
+            reports_ready: None,
         }
     }