Merge branch 'master' into author-relay-block

substrate/runtime-std/without_std.rs

@@ -33,6 +33,8 @@ extern "C" {
 	fn ext_set_storage(key_data: *const u8, key_len: u32, value_data: *const u8, value_len: u32);
 	fn ext_get_allocated_storage(key_data: *const u8, key_len: u32, written_out: *mut u32) -> *mut u8;
 	fn ext_get_storage_into(key_data: *const u8, key_len: u32, value_data: *mut u8, value_len: u32, value_offset: u32) -> u32;
+	fn ext_storage_root(result: *mut u8);
+	fn ext_enumerated_trie_root(values_data: *const u8, values_len: u32, lens_data: *const u32, lens_len: u32, result: *mut u8);
 	fn ext_chain_id() -> u64;
 	fn ext_blake2_256(data: *const u8, len: u32, out: *mut u8);
 	fn ext_twox_128(data: *const u8, len: u32, out: *mut u8);
@@ -67,6 +69,30 @@ pub fn read_storage(key: &[u8], value_out: &mut [u8], value_offset: usize) -> us
 	}
 }
 
+/// The current storage's root.
+pub fn storage_root() -> [u8; 32] {
+	let mut result: [u8; 32] = Default::default();
+	unsafe {
+		ext_storage_root(result.as_mut_ptr());
+	}
+	result
+}
+
+/// A trie root calculated from enumerated values.
+pub fn enumerated_trie_root(values: &[&[u8]]) -> [u8; 32] {
+	let lens = values.iter().map(|v| (v.len() as u32).to_le()).collect::<Vec<_>>();
+	let values = values.iter().fold(Vec::new(), |mut acc, sl| { acc.extend_from_slice(sl); acc });
+	let mut result: [u8; 32] = Default::default();
+	unsafe {
+		ext_enumerated_trie_root(
+			values.as_ptr(), values.len() as u32,
+			lens.as_ptr(), lens.len() as u32,
+			result.as_mut_ptr()
+		);
+	}
+	result
+}
+
 /// The current relay chain identifier.
 pub fn chain_id() -> u64 {
 	unsafe {
@@ -77,7 +103,6 @@ pub fn chain_id() -> u64 {
 /// Conduct a 256-bit Blake2 hash.
 pub fn blake2_256(data: &[u8]) -> [u8; 32] {
 	let mut result: [u8; 32] = Default::default();
-	// guaranteed to write into result.
 	unsafe {
 		ext_blake2_256(data.as_ptr(), data.len() as u32, result.as_mut_ptr());
 	}
@@ -87,7 +112,6 @@ pub fn blake2_256(data: &[u8]) -> [u8; 32] {
 /// Conduct four XX hashes to give a 256-bit result.
 pub fn twox_256(data: &[u8]) -> [u8; 32] {
 	let mut result: [u8; 32] = Default::default();
-	// guaranteed to write into result.
 	unsafe {
 		ext_twox_256(data.as_ptr(), data.len() as u32, result.as_mut_ptr());
 	}
@@ -97,7 +121,6 @@ pub fn twox_256(data: &[u8]) -> [u8; 32] {
 /// Conduct two XX hashes to give a 128-bit result.
 pub fn twox_128(data: &[u8]) -> [u8; 16] {
 	let mut result: [u8; 16] = Default::default();
-	// guaranteed to write into result.
 	unsafe {
 		ext_twox_128(data.as_ptr(), data.len() as u32, result.as_mut_ptr());
 	}