initial commit

.gitignore

+# Ignore build artifacts from the local tests sub-crate.
+/target/
+/pdsl_tests/target/
+/pdsl_core/target/
+/pdsl_derive/target/
+
+/design/
+/pdsl_tests/examples/
+
+# Ignore backup files creates by cargo fmt.
+**/*.rs.bk
+
+# Remove Cargo.lock when creating an executable, leave it for libraries
+# More information here http://doc.crates.io/guide.html#cargotoml-vs-cargolock
+Cargo.lock

Cargo.toml

+[workspace]
+
+members = [
+	"pdsl_core",
+	"pdsl_derive",
+	"pdsl_tests"
+]
+
+[profile.release]
+panic = "abort"
+lto = true

README.md

+# pDSL - Parity's DSL for Smart Contracts
+
+**IMPORTANT NOTE:** THIS IS WORK IN PROGRESS! Do not expect this to be working of final in any way.
+
+Write WebAssembly based smart contracts in Rust operating on Substrate.
+
+## Structure
+
+This repository currently exists of three different sub modules.
+
+- `pdsl_core`: Defines the core utilities and abstractions to declare, implement, test and execute smart contracts.
+- `pdsl_derive`: Utilities to simplify writing smart contract code.
+- `pdsl_test`: Test framework for the above.
+
+While users can use only `pdsl_core` to write entire smart contracts it is recommended to use this library via `pdsl_derive`.
+
+## Design Goals
+
+- `pdsl_core`
+	- Safe and unsafe abstractions
+	- Library-only solution
+	- Stand alone for writing smart contracts
+	- Facility to test and even benchmark contracts off-chain
+	- No tricky-intransparent abstractions
+
+- `pdsl_derive`
+	- eDSL that makes writing smart contracts using `pdsl_core` easier
+	- Based only on `pdsl_core`
+	- Empower your smart contracts by Rust's
+		- safety guarantees
+		- performance characteristics 
+
+## License
+
+The entire code within this repository is licensed under the [GLP-v3](LICENSE). Please [contact us](https://www.parity.io/contact/) if you have questions about the licensing of our products.

pdsl_core/Cargo.toml

+[package]
+name = "pdsl_core"
+version = "0.1.0"
+authors = ["Herobird <robbepop@web.de>"]
+edition = "2018"
+
+license = "MIT/Apache-2.0"
+readme = "README.md"
+
+# repository = "https://github.com/robbepop/substrate-contract"
+# homepage = "https://github.com/robbepop/substrate-contract"
+# documentation = "https://robbepop.github.io/pwasm-abi/substrate-contract/"
+
+description = "[pDSL: Parity eDSL] Rust based eDSL for writing smart contracts for Substrate"
+keywords = ["wasm", "parity", "webassembly", "blockchain", "edsl"]
+categories = ["no-std", "embedded"]
+
+include = ["Cargo.toml", "src/**/*.rs", "README.md", "LICENSE"]
+
+[dependencies]
+parity-codec = { version = "2.0" }
+parity-codec-derive = { version = "2.0" }
+tiny-keccak = "1.4"
+
+[dev-dependencies]
+lazy_static = "1.2"

pdsl_core/LICENSE

+../LICENSE
\ No newline at end of file

pdsl_core/README.md

+../README.md
\ No newline at end of file

pdsl_core/src/collections/mod.rs

+//! Collections operating on contract storage.
+//!
+//! Collection types that safely abstract from contract storage.
+//! Users are recommended to use them instead of unsafe abstractions
+//! such as `Key` or `Storage`.
+//!
+//! Currently supported data structures are:
+//!
+//! - `StorageVec`: Similar to Rust's `Vec`
+//! - `StorageMap`: Similar to Rust's `HashMap`
+//!
+//! Beware that the similarities are only meant for their respective APIs.
+//! Internally they are structured completely different and may even
+//! exhibit different efficiency characteristics.
+
+pub mod storage_map;
+mod storage_vec;
+
+pub use self::{
+	storage_vec::{
+		StorageVec,
+	},
+	storage_map::{
+		StorageMap,
+	},
+};

pdsl_core/src/collections/storage_map.rs

+use crate::storage::{Key, Synced, SyncedChunk};
+use crate::hash::{self, HashAsKeccak256};
+
+use std::borrow::Borrow;
+
+/// Mapping stored in the contract storage.
+///
+/// # Note
+///
+/// This performs a quadratic probing on the next 2^32 slots
+/// following its initial key. So it can store up to 2^32 elements in total.
+///
+/// Instead of storing element values (`V`) directly, it stores
+/// storage map entries of `(K, V)` instead. This allows to represent
+/// the storage that is associated to the storage map to be in three
+/// different states.
+///
+/// 1. Occupied slot with key and value.
+/// 2. Removed slot that was occupied before.
+/// 3. Empty slot when there never was an insertion for this storage slot.
+///
+/// This distinction is important for the quadratic map probing.
+#[derive(Debug)]
+pub struct StorageMap<K, V> {
+	/// The storage key to the length of this storage map.
+	len: Synced<u32>,
+	/// The first half of the entry buffer is equal to the key,
+	/// the second half will be replaced with the respective
+	/// hash of any given key upon usage.
+	///
+	/// Afterwards this value is hashed again and used as key
+	/// into the contract storage.
+	entries: SyncedChunk<Entry<K, V>>,
+}
+
+/// An entry of a storage map.
+///
+/// This can either store the entries key and value
+/// or represent an entry that was removed after it
+/// has been occupied with key and value.
+#[derive(Debug, Clone, PartialEq, Eq)]
+#[derive(parity_codec_derive::Encode, parity_codec_derive::Decode)]
+pub enum Entry<K, V> {
+	/// An occupied slot with a key and a value.
+	Occupied(OccupiedEntry<K, V>),
+	/// A removed slot that was occupied before.
+	Removed,
+}
+
+/// An occupied entry of a storage map.
+#[derive(Debug, Clone, PartialEq, Eq)]
+#[derive(parity_codec_derive::Encode, parity_codec_derive::Decode)]
+pub struct OccupiedEntry<K, V> {
+	/// The entry's key.
+	key: K,
+	/// The entry's value.
+	val: V,
+}
+
+impl<K, V> From<Key> for StorageMap<K, V>
+where
+	K: parity_codec::Codec,
+	V: parity_codec::Codec,
+{
+	fn from(key: Key) -> Self {
+		StorageMap{
+			len: Synced::from(key),
+			entries: SyncedChunk::from(
+				Key::with_offset(&key, 1)
+			),
+		}
+	}
+}
+
+impl<K, V> StorageMap<K, V> {
+	/// Returns the number of key-value pairs in the map.
+	pub fn len(&self) -> u32 {
+		*self.len.get()
+	}
+
+	/// Returns `true` if the map contains no elements.
+	pub fn is_empty(&self) -> bool {
+		self.len() == 0
+	}
+}
+
+/// Converts the given bytes into a `u32` value.
+///
+/// The first byte in the array will be the most significant byte.
+fn bytes_to_u32(bytes: [u8; 4]) -> u32 {
+	let mut res = 0;
+	res |= (bytes[0] as u32) << 24;
+	res |= (bytes[1] as u32) << 16;
+	res |= (bytes[2] as u32) <<  8;
+	res |= (bytes[3] as u32) <<  0;
+	res
+}
+
+/// Converts the given slice into an array with fixed size of 4.
+///
+/// Returns `None` if the slice's length is not 4.
+fn slice_as_array4<T>(bytes: &[T]) -> Option<[T; 4]>
+where
+	T: Default + Copy
+{
+	if bytes.len() != 4 {
+		return None
+	}
+	let mut array = [T::default(); 4];
+	for i in 0..4 {
+		array[i] = bytes[i];
+	}
+	Some(array)
+}
+
+impl<K, V> StorageMap<K, V>
+where
+	K: parity_codec::Codec + HashAsKeccak256 + Eq,
+	V: parity_codec::Codec,
+{
+	/// Probes for a free or usable slot.
+	///
+	/// # Note
+	///
+	/// - Uses quadratic probing.
+	/// - Returns `(true, _)` if there was a key-match of an already
+	///   occupied slot, returns `(false, _)` if the found slot is empty.
+	/// - Returns `(_, n)` if `n` is the found probed index.
+	fn probe<Q>(&self, key: &Q, inserting: bool) -> (bool, u32)
+	where
+		K: Borrow<Q>,
+		Q: HashAsKeccak256 + Eq
+	{
+		// Convert the first 4 bytes in the keccak256 hash
+		// of the key into a big-endian unsigned integer.
+		let probe_start = bytes_to_u32(
+			slice_as_array4(
+				&(hash::keccak256(key.borrow())[0..4])
+			).expect(
+				"[pdsl_core::StorageMap::insert] Error \
+				 couldn't convert to probe_start byte array"
+			)
+		);
+		// This is the offset for the quadratic probing.
+		let mut probe_hops = 0;
+		let mut probe_offset = 0;
+		'outer: loop {
+			let probe_index = probe_start.wrapping_add(probe_offset);
+			match self.entries.get(probe_index) {
+				Some(Entry::Occupied(entry)) => {
+					if key == entry.key.borrow() {
+						return (true, probe_index)
+					}
+					// Need to jump using quadratic probing.
+					probe_hops += 1;
+					probe_offset = probe_hops * probe_hops;
+					continue 'outer
+				}
+				Some(Entry::Removed) | None => {
+					// We can insert into this slot.
+					if inserting {
+						return (false, probe_index)
+					}
+					continue 'outer
+				}
+			}
+		}
+	}
+
+	/// Probes for a free or usable slot while inserting.
+	///
+	/// # Note
+	///
+	/// For more information refer to the `fn probe` documentation.
+	fn probe_inserting<Q>(&self, key: &Q) -> (bool, u32)
+	where
+		K: Borrow<Q>,
+		Q: HashAsKeccak256 + Eq
+	{
+		self.probe(key, true)
+	}
+
+	/// Probes for a free or usable slot while inspecting.
+	///
+	/// # Note
+	///
+	/// For more information refer to the `fn probe` documentation.
+	fn probe_inspecting<Q>(&self, key: &Q) -> u32
+	where
+		K: Borrow<Q>,
+		Q: HashAsKeccak256 + Eq
+	{
+		self.probe(key, false).1
+	}
+
+	/// Inserts a key-value pair into the map.
+	///
+	/// If the map did not have this key present, `None` is returned.
+	///
+	/// If the map did have this key present, the value is updated,
+	/// and the old value is returned.
+	/// The key is not updated, though;
+	/// this matters for types that can be == without being identical.
+	/// See the module-level documentation for more.
+	pub fn insert(&mut self, key: K, val: V) -> Option<V> {
+		match self.probe_inserting(&key) {
+			(true, probe_index) => {
+				// Keys match, values might not.
+				// So we have to overwrite this entry with the new value.
+				let old = self.entries.remove(probe_index);
+				self.entries.insert(
+					probe_index, Entry::Occupied(OccupiedEntry{key, val})
+				);
+				return match old.unwrap() {
+					Entry::Occupied(OccupiedEntry{val, ..}) => Some(val),
+					Entry::Removed => None,
+				}
+			}
+			(false, probe_index) => {
+				// We can insert into this slot.
+				self.entries.insert(
+					probe_index,
+					Entry::Occupied(OccupiedEntry{key, val})
+				);
+				return None
+			}
+		}
+	}
+
+	/// Removes a key from the map,
+	/// returning the value at the key if the key was previously in the map.
+	///
+	/// # Note
+	///
+	/// The key may be any borrowed form of the map's key type,
+	/// but Hash and Eq on the borrowed form must match those for the key type.
+	pub fn remove<Q>(&mut self, key: &Q) -> Option<V>
+	where
+		K: Borrow<Q>,
+		Q: HashAsKeccak256 + Eq
+	{
+		let probe_index = self.probe_inspecting(key);
+		match self.entries.remove(probe_index) {
+			Some(Entry::Removed) | None => None,
+			Some(Entry::Occupied(OccupiedEntry{val, ..})) => Some(val),
+		}
+	}
+
+	/// Returns the value corresponding to the key.
+	///
+	/// The key may be any borrowed form of the map's key type,
+	/// but Hash and Eq on the borrowed form must match those for the key type.
+	pub fn get<Q>(&self, key: &Q) -> Option<&V>
+	where
+		K: Borrow<Q>,
+		Q: HashAsKeccak256 + Eq
+	{
+		match self.entry(key) {
+			Some(Entry::Removed) | None => None,
+			Some(Entry::Occupied(OccupiedEntry{val, ..})) => Some(val),
+		}
+	}
+
+	/// Returns the entry corresponding to the key.
+	///
+	/// The key may be any borrowed form of the map's key type,
+	/// but Hash and Eq on the borrowed form must match those for the key type.
+	pub fn entry<Q>(&self, key: &Q) -> Option<&Entry<K, V>>
+	where
+		K: Borrow<Q>,
+		Q: HashAsKeccak256 + Eq
+	{
+		self.entries.get(self.probe_inspecting(key))
+	}
+}

pdsl_core/src/collections/storage_vec.rs

+use crate::storage::{
+	Key,
+	Synced,
+	SyncedRef,
+	SyncedChunk,
+};
+
+use std::marker::PhantomData;
+
+/// A storage vector capable of storing elements in the storage
+/// in contiguous hashes.
+///
+/// # Note
+///
+/// - Due to the architecture of the storage this storage vector is
+/// very different from an actual vector such as Rust's `Vec`.
+/// Even though its hashes with which it stores elements in the storage
+/// are contiguous doesn't mean the elements are stored in a single
+/// dense block of memory.
+///
+/// - This can be used as a building block for other storage data structures.
+#[derive(Debug)]
+pub struct StorageVec<T> {
+	/// The length of this storage vec.
+	len: Synced<u32>,
+	/// Synced chunk of elements.
+	synced: SyncedChunk<T>,
+	/// Marker to make Rust's type system happy.
+	marker: PhantomData<T>,
+}
+
+impl<T> From<Key> for StorageVec<T> {
+	fn from(key: Key) -> Self {
+		StorageVec{
+			len: Synced::from(key),
+			synced: SyncedChunk::from(
+				Key::with_offset(&key, 1)
+			),
+			marker: PhantomData,
+		}
+	}
+}
+
+impl<T> StorageVec<T> {
+	/// Returns the number of elements in the vector.
+	pub fn len(&self) -> u32 {
+		*self.len.get()
+	}
+
+	/// Returns `true` if the vector contains no elements.
+	pub fn is_empty(&self) -> bool {
+		self.len() == 0
+	}
+}
+
+impl<T> StorageVec<T>
+where
+	T: parity_codec::Codec
+{
+	/// Returns the n-th elements of this storage vec.
+	///
+	/// Returns `None` if given `n` is out of bounds.
+	pub fn get(&self, n: u32) -> Option<&T> {
+		if n >= self.len() {
+			return None
+		}
+		// Some(self.storage_at(n).get())
+		Some(self.synced.get(n).expect("TODO"))
+	}
+
+	/// Returns a mutable reference to the n-th element of this storage vec.
+	///
+	/// Returns `None` if given `n` is out of bounds.
+	pub fn get_mut(&mut self, n: u32) -> Option<SyncedRef<T>> {
+		if n >= self.len() {
+			return None
+		}
+		Some(self.get_mut(n).expect("TODO"))
+	}
+
+	/// Appends an element to the back of a collection.
+	pub fn push(&mut self, val: T) {
+		if self.len() == u32::max_value() {
+			panic!(
+				"[pdsl_core::StorageVec::push] \
+				 Error: cannot push more elements than `u32::MAX`"
+			)
+		}
+		let last_index = self.len();
+		self.len.set(last_index + 1);
+		self.synced.insert(last_index, val)
+	}
+
+	/// Removes the last element from a vector and returns it, or `None` if it is empty.
+	pub fn pop(&mut self) -> Option<T> {
+		if self.len() == 0 {
+			return None
+		}
+		let last_index = self.len() - 1;
+		Some(self.synced.remove(last_index).expect("TODO"))
+	}
+
+	/// Removes an element from the vector and returns it.
+	/// 
+	/// The removed element is replaced by the last element of the vector.
+	/// This does not preserve ordering, but is O(1).
+	/// 
+	/// Returns `None` if empty or if index is out of bounds.
+	pub fn swap_remove(&mut self, index: u32) -> Option<T> {
+		if index >= self.len() {
+			return None
+		}
+		if self.len() <= 1 {
+			return self.pop()
+		}
+		let ret = self
+			.synced.remove(index)
+			.expect(
+				"[pdsl_core::StorageVec::swap_remove] \
+				 Error: expected element at given index"
+			);
+		let last = self
+			.pop()
+			.expect(
+				"[pdsl_core::StorageVec::swap_remove] \
+				 Error: expected element for pop()"
+			);
+		self.synced.insert(index, last);
+		Some(ret)
+	}
+}
+
+#[cfg(test)]
+mod test {
+	use super::*;
+
+	use crate::env::{Env, TestEnv};
+	use parity_codec::{Encode};
+
+	#[test]
+	fn new() {
+		let k0 = Key([0x0; 32]);
+		{
+			TestEnv::store(k0.as_bytes(), &u32::encode(&0));
+			assert_eq!(StorageVec::<i32>::from(k0).len(), 0);
+		}
+		{
+			TestEnv::reset(); // Not necesarily required.
+			TestEnv::store(k0.as_bytes(), &u32::encode(&42));
+			assert_eq!(StorageVec::<i32>::from(k0).len(), 42);
+		}
+	}
+}

pdsl_core/src/env.rs

+//! Externally defined and provded functionality.
+//!
+//! Refer to substrate SRML for more information.
+
+/// Refer to substrate SRML contract module for more documentation.
+pub mod c_abi {
+	extern "C" {
+		pub fn ext_create(
+			init_code_ptr: u32,
+			init_code_len: u32,
+			gas: u64,
+			value_ptr: u32,
+			value_len: u32,
+			input_data_ptr: u32,
+			input_data_len: u32
+		) -> u32;
+
+		pub fn ext_call(
+			callee_ptr: u32,
+			callee_len: u32,
+			gas: u64,
+			value_ptr: u32,
+			value_len: u32,
+			input_data_ptr: u32,
+			input_data_len: u32
+		) -> u32;
+
+		pub fn ext_set_storage(key_ptr: u32, value_non_null: u32, value_ptr: u32, value_len: u32);
+		pub fn ext_get_storage(key_ptr: u32) -> u32;
+
+		pub fn ext_scratch_size() -> u32;
+		pub fn ext_scratch_copy(dest_ptr: u32, offset: u32, len: u32);
+
+		pub fn ext_input_size() -> u32;
+		pub fn ext_input_copy(dest_ptr: u32, offset: u32, len: u32);
+
+		pub fn ext_return(data_ptr: u32, data_len: u32) -> !;
+	}
+}
+
+/// The evironment API usable by SRML contracts.
+pub trait Env {
+	/// Stores the given value under the given key.
+	fn store(key: &[u8], value: &[u8]);
+	/// Clears the value stored under the given key.
+	fn clear(key: &[u8]);
+	/// Loads data stored under the given key.
+	fn load(key: &[u8]) -> Option<Vec<u8>>;
+	/// Loads input data for contract execution.
+	fn input() -> Vec<u8>;
+	/// Returns from the contract execution with the given value.
+	fn return_(value: &[u8]) -> !;
+}
+
+#[cfg(not(test))]
+mod default {
+	use super::*;
+
+	/// The default SRML contracts environment.
+	pub struct DefaultEnv;
+
+	impl Env for DefaultEnv {
+		fn store(key: &[u8], value: &[u8]) {
+			unsafe {
+				c_abi::ext_set_storage(
+					key.as_ptr() as u32,
+					1,
+					value.as_ptr() as u32,
+					value.len() as u32
+				);
+			}
+		}
+
+		fn clear(key: &[u8]) {
+			unsafe {
+				c_abi::ext_set_storage(key.as_ptr() as u32, 0, 0, 0)