From d8ca68426060d8538fcce0590024029837adbbdb Mon Sep 17 00:00:00 2001
From: Gary Yu <gairy.yu@gmail.com>
Date: Mon, 1 Oct 2018 21:58:50 +0800
Subject: [PATCH] fix: in case of all known, update header_head and sync_head
 (#1619)

* fix: in case of all known for Headers received, update sync_head to the last header

* refactor: push this logic down into pipe
---
 chain/src/pipe.rs              | 19 +++++++++++++++++++
 servers/src/common/adapters.rs |  7 -------
 2 files changed, 19 insertions(+), 7 deletions(-)

diff --git a/chain/src/pipe.rs b/chain/src/pipe.rs
index 6c3f9d784..f3ffefa4e 100644
--- a/chain/src/pipe.rs
+++ b/chain/src/pipe.rs
@@ -205,6 +205,24 @@ pub fn sync_block_headers(
 	ctx: &mut BlockContext,
 	batch: &mut store::Batch,
 ) -> Result<(), Error> {
+	let bhs_last = headers.last().unwrap().clone();
+	let last_h = bhs_last.hash();
+	if let Ok(_) = batch.get_block_header(&last_h) {
+		info!(
+			LOGGER,
+			"All known, ignoring. Update sync_head to {} at {}", last_h, bhs_last.height,
+		);
+
+		let res = update_sync_head(&bhs_last, batch);
+		if let &Err(ref e) = &res {
+			error!(
+				LOGGER,
+				"Block header {} update_sync_head fail: {:?}", last_h, e
+			);
+		}
+		return Ok(());
+	}
+
 	if let Some(header) = headers.first() {
 		debug!(
 			LOGGER,
@@ -664,6 +682,7 @@ fn update_sync_head(bh: &BlockHeader, batch: &mut store::Batch) -> Result<(), Er
 	Ok(())
 }
 
+/// Update the header head so we can keep syncing from where we left off.
 fn update_header_head(
 	bh: &BlockHeader,
 	ctx: &mut BlockContext,
diff --git a/servers/src/common/adapters.rs b/servers/src/common/adapters.rs
index e0a429dba..ccbb15765 100644
--- a/servers/src/common/adapters.rs
+++ b/servers/src/common/adapters.rs
@@ -263,13 +263,6 @@ impl p2p::ChainAdapter for NetToChainAdapter {
 			return false;
 		}
 
-		// headers will just set us backward if even the last is unknown
-		let last_h = bhs.last().unwrap().hash();
-		if let Ok(_) = w(&self.chain).get_block_header(&last_h) {
-			info!(LOGGER, "All known, ignoring");
-			return true;
-		}
-
 		// try to add headers to our header chain
 		let res = w(&self.chain).sync_block_headers(&bhs, self.chain_opts());
 		if let &Err(ref e) = &res {