Rlp decode returns Result

ethcore/light/src/client/header_chain.rs

@@ -228,15 +228,15 @@ impl HeaderChain {
 		let decoded_header = spec.genesis_header();
 
 		let chain = if let Some(current) = db.get(col, CURRENT_KEY)? {
-			let curr : BestAndLatest = ::rlp::decode(&current);
+			let curr : BestAndLatest = ::rlp::decode(&current)?;
 
 			let mut cur_number = curr.latest_num;
 			let mut candidates = BTreeMap::new();
 
 			// load all era entries, referenced headers within them,
 			// and live epoch proofs.
 			while let Some(entry) = db.get(col, era_key(cur_number).as_bytes())? {
-				let entry: Entry = ::rlp::decode(&entry);
+				let entry: Entry = ::rlp::decode(&entry)?;
 				trace!(target: "chain", "loaded header chain entry for era {} with {} candidates",
 					cur_number, entry.candidates.len());
 
@@ -524,7 +524,16 @@ impl HeaderChain {
 											None
 										}
 										Ok(None) => panic!("stored candidates always have corresponding headers; qed"),
-										Ok(Some(header)) => Some((epoch_transition, ::rlp::decode(&header))),
+										Ok(Some(header)) => {
+											match ::rlp::decode(&header) {
+												Ok(decoded_header) => Some((epoch_transition, decoded_header)),
+												Err(e) => {
+													warn!(target: "chain", "Error decoding header: {}\n", e);
+													None
+												}
+											}
+
+										},
 									};
 								}
 							}
@@ -591,7 +600,7 @@ impl HeaderChain {
 													in an inconsistent state", h_num);
 								ErrorKind::Database(msg.into())
 							})?;
-						::rlp::decode(&bytes)
+						::rlp::decode(&bytes)?
 					};
 
 					let total_difficulty = entry.candidates.iter()
@@ -604,9 +613,9 @@ impl HeaderChain {
 						.total_difficulty;
 
 					break Ok(Some(SpecHardcodedSync {
-						header: header,
-						total_difficulty: total_difficulty,
-						chts: chts,
+						header,
+						total_difficulty,
+						chts,
 					}));
 				},
 				None => {
@@ -742,7 +751,17 @@ impl HeaderChain {
 	/// so including it within a CHT would be redundant.
 	pub fn cht_root(&self, n: usize) -> Option<H256> {
 		match self.db.get(self.col, cht_key(n as u64).as_bytes()) {
-			Ok(val) => val.map(|x| ::rlp::decode(&x)),
+			Ok(db_fetch) => {
+				db_fetch.map_or(None, |bytes| {
+					match ::rlp::decode(&bytes) {
+						Ok(h256) => Some(h256),
+						Err(e) => {
+							warn!(target: "chain", "Error decoding data from database: {}", e);
+							None
+						}
+					}
+				})
+			},
 			Err(e) => {
 				warn!(target: "chain", "Error reading from database: {}", e);
 				None
@@ -793,7 +812,17 @@ impl HeaderChain {
 	pub fn pending_transition(&self, hash: H256) -> Option<PendingEpochTransition> {
 		let key = pending_transition_key(hash);
 		match self.db.get(self.col, &*key) {
-			Ok(val) => val.map(|x| ::rlp::decode(&x)),
+			Ok(db_fetch) => {
+				db_fetch.map_or(None, |bytes| {
+					match ::rlp::decode(&bytes) {
+						Ok(pending_transition) => Some(pending_transition),
+						Err(e) => {
+							warn!(target: "chain", "Error decoding data from database: {}", e);
+							None
+						}
+					}
+				})
+			},
 			Err(e) => {
 				warn!(target: "chain", "Error reading from database: {}", e);
 				None
@@ -1192,7 +1221,7 @@ mod tests {
 
 		let cache = Arc::new(Mutex::new(Cache::new(Default::default(), Duration::from_secs(6 * 3600))));
 
-		let chain = HeaderChain::new(db.clone(), None, &spec, cache, HardcodedSync::Allow).unwrap();
+		let chain = HeaderChain::new(db.clone(), None, &spec, cache, HardcodedSync::Allow).expect("failed to instantiate a new HeaderChain");
 
 		let mut parent_hash = genesis_header.hash();
 		let mut rolling_timestamp = genesis_header.timestamp();
@@ -1211,14 +1240,14 @@ mod tests {
 			parent_hash = header.hash();
 
 			let mut tx = db.transaction();
-			let pending = chain.insert(&mut tx, header, None).unwrap();
+			let pending = chain.insert(&mut tx, header, None).expect("failed inserting a transaction");
 			db.write(tx).unwrap();
 			chain.apply_pending(pending);
 
 			rolling_timestamp += 10;
 		}
 
-		let hardcoded_sync = chain.read_hardcoded_sync().unwrap().unwrap();
+		let hardcoded_sync = chain.read_hardcoded_sync().expect("failed reading hardcoded sync").expect("failed unwrapping hardcoded sync");
 		assert_eq!(hardcoded_sync.chts.len(), 3);
 		assert_eq!(hardcoded_sync.total_difficulty, total_difficulty);
 		let decoded: Header = hardcoded_sync.header.decode();

ethcore/light/src/net/request_credits.rs

@@ -407,7 +407,7 @@ mod tests {
 		let costs = CostTable::default();
 		let serialized = ::rlp::encode(&costs);
 
-		let new_costs: CostTable = ::rlp::decode(&*serialized);
+		let new_costs: CostTable = ::rlp::decode(&*serialized).unwrap();
 
 		assert_eq!(costs, new_costs);
 	}

ethcore/light/src/types/request/mod.rs

@@ -1642,7 +1642,7 @@ mod tests {
 	{
 		// check as single value.
 		let bytes = ::rlp::encode(&val);
-		let new_val: T = ::rlp::decode(&bytes);
+		let new_val: T = ::rlp::decode(&bytes).unwrap();
 		assert_eq!(val, new_val);
 
 		// check as list containing single value.

ethcore/src/blockchain/blockchain.rs

@@ -430,7 +430,10 @@ impl<'a> Iterator for EpochTransitionIter<'a> {
 				return None
 			}
 
-			let transitions: EpochTransitions = ::rlp::decode(&val[..]);
+			let transitions: EpochTransitions = match ::rlp::decode(&val[..]) {
+				Ok(decoded) => decoded,
+				Err(_) => return None
+			};
 
 			// if there are multiple candidates, at most one will be on the
 			// canon chain.

ethcore/src/db.rs

@@ -218,11 +218,18 @@ impl Writable for DBTransaction {
 }
 
 impl<KVDB: KeyValueDB + ?Sized> Readable for KVDB {
-	fn read<T, R>(&self, col: Option<u32>, key: &Key<T, Target = R>) -> Option<T> where T: rlp::Decodable, R: Deref<Target = [u8]> {
+	fn read<T, R>(&self, col: Option<u32>, key: &Key<T, Target = R>) -> Option<T>
+		where T: rlp::Decodable, R: Deref<Target = [u8]> {
 		let result = self.get(col, &key.key());
 
 		match result {
-			Ok(option) => option.map(|v| rlp::decode(&v)),
+			Ok(option) => option.map(|v| match rlp::decode(&v){
+				Ok(decoded_rlp) => decoded_rlp,
+				//REVIEW: Should we panic here?
+				Err(decode_err) => {
+					panic!("decoding db value failed, key={:?}, err={}", &key.key() as &[u8], decode_err)
+				}
+			}),
 			Err(err) => {
 				panic!("db get failed, key: {:?}, err: {:?}", &key.key() as &[u8], err);
 			}

ethcore/src/encoded.rs

@@ -48,7 +48,7 @@ impl Header {
 	pub fn new(encoded: Vec<u8>) -> Self { Header(encoded) }
 
 	/// Upgrade this encoded view to a fully owned `Header` object.
-	pub fn decode(&self) -> FullHeader { ::rlp::decode(&self.0) }
+	pub fn decode(&self) -> FullHeader { ::rlp::decode(&self.0).unwrap_or(FullHeader::default()) } // REVIEW: is the default ok here? Useful? The real fix would be to make `decode` return a `Result` as well.
 
 	/// Get a borrowed header view onto the data.
 	#[inline]
@@ -205,7 +205,7 @@ impl Block {
 	pub fn header_view(&self) -> HeaderView { self.view().header_view() }
 
 	/// Decode to a full block.
-	pub fn decode(&self) -> FullBlock { ::rlp::decode(&self.0) }
+	pub fn decode(&self) -> FullBlock { ::rlp::decode(&self.0).unwrap_or(FullBlock::default()) }
 
 	/// Decode the header.
 	pub fn decode_header(&self) -> FullHeader { self.view().rlp().val_at(0) }

ethcore/src/engines/tendermint/mod.rs

@@ -142,8 +142,10 @@ impl <F> super::EpochVerifier<EthereumMachine> for EpochVerifier<F>
 	}
 
 	fn check_finality_proof(&self, proof: &[u8]) -> Option<Vec<H256>> {
-		let header: Header = ::rlp::decode(proof);
-		self.verify_light(&header).ok().map(|_| vec![header.hash()])
+		match ::rlp::decode(proof) {
+			Ok(header) => self.verify_light(&header).ok().map(|_| vec![header.hash()]),
+			Err(_) => None // REVIEW: log perhaps? Not sure what the policy is.
+		}
 	}
 }
 

ethcore/src/header.rs

@@ -398,7 +398,7 @@ mod tests {
 		let nonce = "88ab4e252a7e8c2a23".from_hex().unwrap();
 		let nonce_decoded = "ab4e252a7e8c2a23".from_hex().unwrap();
 
-		let header: Header = rlp::decode(&header_rlp);
+		let header: Header = rlp::decode(&header_rlp).expect("error decoding header");
 		let seal_fields = header.seal.clone();
 		assert_eq!(seal_fields.len(), 2);
 		assert_eq!(seal_fields[0], mix_hash);
@@ -415,7 +415,7 @@ mod tests {
 		// that's rlp of block header created with ethash engine.
 		let header_rlp = "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".from_hex().unwrap();
 
-		let header: Header = rlp::decode(&header_rlp);
+		let header: Header = rlp::decode(&header_rlp).expect("error decoding header");
 		let encoded_header = rlp::encode(&header).into_vec();
 
 		assert_eq!(header_rlp, encoded_header);

ethcore/src/snapshot/account.rs

@@ -236,7 +236,7 @@ mod tests {
 		};
 
 		let thin_rlp = ::rlp::encode(&account);
-		assert_eq!(::rlp::decode::<BasicAccount>(&thin_rlp), account);
+		assert_eq!(::rlp::decode::<BasicAccount>(&thin_rlp).unwrap(), account);
 
 		let fat_rlps = to_fat_rlps(&keccak(&addr), &account, &AccountDB::new(db.as_hashdb(), &addr), &mut Default::default(), usize::max_value(), usize::max_value()).unwrap();
 		let fat_rlp = Rlp::new(&fat_rlps[0]).at(1).unwrap();
@@ -261,7 +261,7 @@ mod tests {
 		};
 
 		let thin_rlp = ::rlp::encode(&account);
-		assert_eq!(::rlp::decode::<BasicAccount>(&thin_rlp), account);
+		assert_eq!(::rlp::decode::<BasicAccount>(&thin_rlp).unwrap(), account);
 
 		let fat_rlp = to_fat_rlps(&keccak(&addr), &account, &AccountDB::new(db.as_hashdb(), &addr), &mut Default::default(), usize::max_value(), usize::max_value()).unwrap();
 		let fat_rlp = Rlp::new(&fat_rlp[0]).at(1).unwrap();
@@ -286,7 +286,7 @@ mod tests {
 		};
 
 		let thin_rlp = ::rlp::encode(&account);
-		assert_eq!(::rlp::decode::<BasicAccount>(&thin_rlp), account);
+		assert_eq!(::rlp::decode::<BasicAccount>(&thin_rlp).unwrap(), account);
 
 		let fat_rlps = to_fat_rlps(&keccak(addr), &account, &AccountDB::new(db.as_hashdb(), &addr), &mut Default::default(), 500, 1000).unwrap();
 		let mut root = KECCAK_NULL_RLP;

ethcore/src/snapshot/mod.rs

@@ -281,7 +281,7 @@ pub fn chunk_state<'a>(db: &HashDB, root: &H256, writer: &Mutex<SnapshotWriter +
 	// account_key here is the address' hash.
 	for item in account_trie.iter()? {
 		let (account_key, account_data) = item?;
-		let account = ::rlp::decode(&*account_data);
+		let account = ::rlp::decode(&*account_data)?;
 		let account_key_hash = H256::from_slice(&account_key);
 
 		let account_db = AccountDB::from_hash(db, account_key_hash);
@@ -467,10 +467,10 @@ fn rebuild_accounts(
 		*out = (hash, thin_rlp);
 	}
 	if let Some(&(ref hash, ref rlp)) = out_chunk.iter().last() {
-		known_storage_roots.insert(*hash, ::rlp::decode::<BasicAccount>(rlp).storage_root);
+		known_storage_roots.insert(*hash, ::rlp::decode::<BasicAccount>(rlp)?.storage_root);
 	}
 	if let Some(&(ref hash, ref rlp)) = out_chunk.iter().next() {
-		known_storage_roots.insert(*hash, ::rlp::decode::<BasicAccount>(rlp).storage_root);
+		known_storage_roots.insert(*hash, ::rlp::decode::<BasicAccount>(rlp)?.storage_root);
 	}
 	Ok(status)
 }

ethcore/src/snapshot/tests/helpers.rs

@@ -75,7 +75,7 @@ impl StateProducer {
 
 		// sweep once to alter storage tries.
 		for &mut (ref mut address_hash, ref mut account_data) in &mut accounts_to_modify {
-			let mut account: BasicAccount = ::rlp::decode(&*account_data);
+			let mut account: BasicAccount = ::rlp::decode(&*account_data).expect("error decoding basic account");
 			let acct_db = AccountDBMut::from_hash(db, *address_hash);
 			fill_storage(acct_db, &mut account.storage_root, &mut self.storage_seed);
 			*account_data = DBValue::from_vec(::rlp::encode(&account).into_vec());

ethcore/src/snapshot/tests/state.rs

@@ -114,7 +114,7 @@ fn get_code_from_prev_chunk() {
 	// first one will have code inlined,
 	// second will just have its hash.
 	let thin_rlp = acc_stream.out();
-	let acc: BasicAccount = ::rlp::decode(&thin_rlp);
+	let acc: BasicAccount = ::rlp::decode(&thin_rlp).expect("error decoding basic account");
 
 	let mut make_chunk = |acc, hash| {
 		let mut db = MemoryDB::new();

ethcore/src/state/account.rs

@@ -145,8 +145,13 @@ impl Account {
 
 	/// Create a new account from RLP.
 	pub fn from_rlp(rlp: &[u8]) -> Account {
-		let basic: BasicAccount = ::rlp::decode(rlp);
-		basic.into()
+		match ::rlp::decode::<BasicAccount>(rlp) {
+			Ok(basic_account) => basic_account.into(),
+			Err(e) => {
+				error!("from_rlp, Rlp decoding error={}",e);
+				panic!("from_rlp, Rlp decoding error={}",e)
+			}
+		}
 	}
 
 	/// Create a new contract account.
@@ -203,7 +208,14 @@ impl Account {
 		}
 		let db = SecTrieDB::new(db, &self.storage_root)?;
 
-		let item: U256 = db.get_with(key, ::rlp::decode)?.unwrap_or_else(U256::zero);
+		let unwrapping_decoder: fn(&[u8]) -> U256 = |bytes: &[u8]| {
+			match ::rlp::decode(bytes) {
+				Ok(u256) => u256,
+				Err(_) => U256::zero()
+			}
+		};
+
+		let item: U256 = db.get_with(key, unwrapping_decoder)?.unwrap_or_else(U256::zero);
 		let value: H256 = item.into();
 		self.storage_cache.borrow_mut().insert(key.clone(), value.clone());
 		Ok(value)
@@ -478,7 +490,13 @@ impl Account {
 
 		let trie = TrieDB::new(db, &self.storage_root)?;
 		let item: U256 = {
-			let query = (&mut recorder, ::rlp::decode);
+			let unwrapping_decoder: fn(&[u8]) -> U256 = |bytes: &[u8]| {
+				match ::rlp::decode(bytes) {
+					Ok(u256) => u256,
+					Err(_) => U256::zero()
+				}
+			};
+			let query = (&mut recorder, unwrapping_decoder);
 			trie.get_with(&storage_key, query)?.unwrap_or_else(U256::zero)
 		};
 

ethcore/src/state/mod.rs

@@ -1039,7 +1039,10 @@ impl<B: Backend> State<B> {
 		let mut recorder = Recorder::new();
 		let trie = TrieDB::new(self.db.as_hashdb(), &self.root)?;
 		let maybe_account: Option<BasicAccount> = {
-			let query = (&mut recorder, ::rlp::decode);
+			let panicky_decoder = |bytes: &[u8]| {
+				::rlp::decode(bytes).expect(&format!("prove_account, could not query trie for account key={}", &account_key))
+			};
+			let query = (&mut recorder, panicky_decoder);
 			trie.get_with(&account_key, query)?
 		};
 		let account = maybe_account.unwrap_or_else(|| BasicAccount {

ethcore/src/trace/types/flat.rs

@@ -244,7 +244,7 @@ mod tests {
 		]);
 
 		let encoded = ::rlp::encode(&block_traces);
-		let decoded = ::rlp::decode(&encoded);
+		let decoded = ::rlp::decode(&encoded).expect("error decoding block traces");
 		assert_eq!(block_traces, decoded);
 	}
 }

ethcore/transaction/src/transaction.rs

@@ -576,7 +576,8 @@ mod tests {
 
 	#[test]
 	fn sender_test() {
-		let t: UnverifiedTransaction = rlp::decode(&::rustc_hex::FromHex::from_hex("f85f800182520894095e7baea6a6c7c4c2dfeb977efac326af552d870a801ba048b55bfa915ac795c431978d8a6a992b628d557da5ff759b307d495a36649353a0efffd310ac743f371de3b9f7f9cb56c0b28ad43601b4ab949f53faa07bd2c804").unwrap());
+		let bytes = ::rustc_hex::FromHex::from_hex("f85f800182520894095e7baea6a6c7c4c2dfeb977efac326af552d870a801ba048b55bfa915ac795c431978d8a6a992b628d557da5ff759b307d495a36649353a0efffd310ac743f371de3b9f7f9cb56c0b28ad43601b4ab949f53faa07bd2c804").unwrap();
+		let t: UnverifiedTransaction = rlp::decode(&bytes).expect("decoding UnverifiedTransaction failed");
 		assert_eq!(t.data, b"");
 		assert_eq!(t.gas, U256::from(0x5208u64));
 		assert_eq!(t.gas_price, U256::from(0x01u64));
@@ -645,7 +646,7 @@ mod tests {
 		use rustc_hex::FromHex;
 
 		let test_vector = |tx_data: &str, address: &'static str| {
-			let signed = rlp::decode(&FromHex::from_hex(tx_data).unwrap());
+			let signed = rlp::decode(&FromHex::from_hex(tx_data).unwrap()).expect("decoding tx data failed");
 			let signed = SignedTransaction::new(signed).unwrap();
 			assert_eq!(signed.sender(), address.into());
 			println!("chainid: {:?}", signed.chain_id());

ethcore/types/src/receipt.rs

@@ -193,7 +193,7 @@ mod tests {
 		);
 		let encoded = ::rlp::encode(&r);
 		assert_eq!(&encoded[..], &expected[..]);
-		let decoded: Receipt = ::rlp::decode(&encoded);
+		let decoded: Receipt = ::rlp::decode(&encoded).expect("decoding receipt failed");
 		assert_eq!(decoded, r);
 	}
 
@@ -211,7 +211,7 @@ mod tests {
 		);
 		let encoded = ::rlp::encode(&r);
 		assert_eq!(&encoded[..], &expected[..]);
-		let decoded: Receipt = ::rlp::decode(&encoded);
+		let decoded: Receipt = ::rlp::decode(&encoded).expect("decoding receipt failed");
 		assert_eq!(decoded, r);
 	}
 }