From 9e501fe5d0e030791628c07480f25291913b3f34 Mon Sep 17 00:00:00 2001
From: debris <marek.kotewicz@gmail.com>
Date: Mon, 7 Nov 2016 11:20:27 +0100
Subject: [PATCH] shutdown gracefully on incompatible db open

---
 pbtc/commands/import.rs |  2 +-
 pbtc/commands/start.rs  |  2 +-
 pbtc/util.rs            | 12 +++++++-----
 3 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/pbtc/commands/import.rs b/pbtc/commands/import.rs
index 5653ef99..39b045cf 100644
--- a/pbtc/commands/import.rs
+++ b/pbtc/commands/import.rs
@@ -6,7 +6,7 @@ use util::{open_db, init_db};
 pub fn import(cfg: Config, matches: &ArgMatches) -> Result<(), String> {
 	let db = open_db(&cfg);
 	// TODO: this might be unnecessary here!
-	init_db(&cfg, &db);
+	try!(init_db(&cfg, &db));
 
 	let mut writer = create_sync_blocks_writer(db);
 
diff --git a/pbtc/commands/start.rs b/pbtc/commands/start.rs
index 1bf3ef44..5860893d 100644
--- a/pbtc/commands/start.rs
+++ b/pbtc/commands/start.rs
@@ -8,7 +8,7 @@ pub fn start(cfg: config::Config) -> Result<(), String> {
 	let mut el = p2p::event_loop();
 
 	let db = open_db(&cfg);
-	init_db(&cfg, &db);
+	try!(init_db(&cfg, &db));
 
 	let p2p_cfg = p2p::Config {
 		threads: 4,
diff --git a/pbtc/util.rs b/pbtc/util.rs
index 112d6723..768f247d 100644
--- a/pbtc/util.rs
+++ b/pbtc/util.rs
@@ -23,13 +23,15 @@ pub fn node_table_path() -> PathBuf {
 	node_table
 }
 
-pub fn init_db(cfg: &Config, db: &Arc<db::Store>) {
+pub fn init_db(cfg: &Config, db: &Arc<db::Store>) -> Result<(), String> {
 	// insert genesis block if db is empty
 	let genesis_block = cfg.magic.genesis_block();
 	match db.block_hash(0) {
-		Some(ref db_genesis_block_hash) if db_genesis_block_hash != &genesis_block.hash() => panic!("Trying to open database with incompatible genesis block"),
-		Some(_) => (),
-		None => db.insert_block(&genesis_block)
-			.expect("Failed to insert genesis block to the database"),
+		Some(ref db_genesis_block_hash) if db_genesis_block_hash != &genesis_block.hash() => Err("Trying to open database with incompatible genesis block".into()),
+		Some(_) => Ok(()),
+		None => {
+			db.insert_block(&genesis_block).expect("Failed to insert genesis block to the database");
+			Ok(())
+		}
 	}
 }