move additional_info to engines, fixes registry on non-ethash chains

ethcore/src/engines/mod.rs

@@ -191,9 +191,6 @@ pub trait Engine<M: Machine>: Sync + Send {
 	/// Additional engine-specific information for the user/developer concerning `header`.
 	fn extra_info(&self, _header: &M::Header) -> BTreeMap<String, String> { BTreeMap::new() }
 
-	/// Additional information.
-	fn additional_params(&self) -> HashMap<String, String> { HashMap::new() }
-
 	/// Maximum number of uncles a block is allowed to declare.
 	fn maximum_uncle_count(&self) -> usize { 2 }
 	/// The number of generations back that uncles can be.
@@ -396,6 +393,11 @@ pub trait EthEngine: Engine<::machine::EthereumMachine> {
 	fn supports_wasm(&self) -> bool {
 		self.machine().supports_wasm()
 	}
+
+	/// Additional information.
+	fn additional_params(&self) -> HashMap<String, String> {
+		self.machine().additional_params()
+	}
 }
 
 // convenience wrappers for existing functions.

ethcore/src/ethereum/ethash.rs

@@ -16,7 +16,7 @@
 
 use std::path::Path;
 use std::cmp;
-use std::collections::{BTreeMap, HashMap};
+use std::collections::BTreeMap;
 use std::sync::Arc;
 use hash::{KECCAK_EMPTY_LIST_RLP};
 use ethash::{quick_get_difficulty, slow_hash_block_number, EthashManager, OptimizeFor};
@@ -26,7 +26,7 @@ use unexpected::{OutOfBounds, Mismatch};
 use block::*;
 use error::{BlockError, Error};
 use header::Header;
-use engines::{self, Engine, EthEngine};
+use engines::{self, Engine};
 use ethjson;
 use rlp::{self, UntrustedRlp};
 use machine::EthereumMachine;
@@ -150,8 +150,6 @@ impl Engine<EthereumMachine> for Arc<Ethash> {
 	// Two fields - nonce and mix.
 	fn seal_fields(&self) -> usize { 2 }
 
-	fn additional_params(&self) -> HashMap<String, String> { hash_map!["registrar".to_owned() => self.params().registrar.hex()] }
-
 	/// Additional engine-specific information for the user/developer concerning `header`.
 	fn extra_info(&self, header: &Header) -> BTreeMap<String, String> {
 		if header.seal().len() == self.seal_fields() {

ethcore/src/machine.rs

@@ -16,7 +16,7 @@
 
 //! Ethereum-like state machine definition.
 
-use std::collections::BTreeMap;
+use std::collections::{BTreeMap, HashMap};
 use std::cmp;
 use std::sync::Arc;
 
@@ -378,6 +378,13 @@ impl EthereumMachine {
 	pub fn supports_wasm(&self) -> bool {
 		self.params().wasm
 	}
+
+	/// Additional params.
+	pub fn additional_params(&self) -> HashMap<String, String> {
+		hash_map![
+			"registrar".to_owned() => self.params.registrar.hex()
+		]
+	}
 }
 
 /// Auxiliary data fetcher for an Ethereum machine. In Ethereum-like machines