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Cargo.toml

+[package]
+name = "ewasm_api"
+version = "0.9.1"
+authors = ["Alex Beregszaszi <alex@rtfs.hu>", "Jake Lang <jak3lang@gmail.com>"]
+license = "Apache-2.0"
+repository = "https://github.com/ewasm/ewasm-rust-api"
+description = "ewasm API for Rust"
+edition = "2018"
+
+[dependencies]
+cfg-if = "0.1.7"
+wee_alloc = { version = "0.4.4", optional = true }
+qimalloc = { version = "0.1", optional = true }
+ethabi = { version = "8.0.0", path = "./libs/ethabi" }
+
+[features]
+default = ["std", "wee_alloc"]
+std = []
+debug = []
+experimental = []

LICENSE

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README.md

+# ewasm-rust-api
+
+# Usage
+
+Add the dependency, as usual:
+```toml
+[dependencies]
+ewasm_api = { git = "https://github.com/WuEcho/ewasm-rust-api", tag = "0.9" }
+```
+
+In your project, include the prelude:
+```rust
+use ewasm_api::prelude::*;
+```
+
+Other modules are available as well, outside of the prelude. Refer to the documentation for more info.
+
+`ewasm-rust-api` builds with various feature sets:
+- `default`: Builds with `wee_alloc` as the global allocator and with the Rust standard library.
+- `qimalloc`: Builds with [qimalloc](https://github.com/wasmx/qimalloc) as the global allocator.
+- `debug`: Exposes the debugging interface.
+- `experimental`: Exposes the experimental bignum system library API.
+
+Further documentation is available [here](https://docs.rs/ewasm_api/).
+
+## Author(s)
+
+Alex Beregszaszi, Jake Lang
+
+## License
+
+Apache 2.0
+
+

circle.yml

+version: 2
+
+jobs:
+  build:
+    docker:
+      - image: rust:1
+    steps:
+      - checkout
+      - run:
+          name: Update rustc
+          command: |
+            rustup target add wasm32-unknown-unknown
+            rustup component add rustfmt-preview
+            rustup update
+      - run:
+           name: Check formatting
+           command: |
+             rustfmt --version
+             cargo fmt
+             git diff --exit-code
+      - run:
+          name: Test
+          command: cargo test --target=x86_64-unknown-linux-gnu
+      - run:
+          name: Build
+          command: |
+             cargo build --release
+             # debug
+             cargo build
+             cargo build --release --no-default-features
+             cargo build --release --features debug
+             cargo build --release --no-default-features --features debug
+             cargo build --release --features experimental
+             cargo build --release --no-default-features --features experimental
+             cargo build --release --features experimental,debug
+             cargo build --release --no-default-features --features experimental,debug
+             cargo build --release --features wee_alloc
+             cargo build --release --features qimalloc

libs/ethabi/Cargo.toml

+[package]
+name = "ethabi"
+version = "8.0.1"
+authors = ["Parity Technologies <admin@parity.io>"]
+homepage = "https://github.com/paritytech/ethabi"
+license = "MIT/Apache-2.0"
+keywords = ["ethereum", "eth", "abi", "solidity", "cli"]
+description = "Easy to use conversion of ethereum contract calls to bytecode."
+
+[dependencies]
+rustc-hex = "2.0"
+serde = "1.0"
+serde_json = "1.0"
+serde_derive = "1.0"
+tiny-keccak = "1.4"
+error-chain = { version = "0.12", default-features = false }
+ethereum-types = "0.6.0"
+
+[dev-dependencies]
+hex-literal = "0.2.0"
+paste = "0.1.5"
+
+[features]
+backtrace = ["error-chain/backtrace"]
+
+[badges]
+travis-ci = { repository = "paritytech/ethabi", branch = "master" }
+coveralls = { repository = "paritytech/ethabi", branch = "master" }

libs/ethabi/src/constructor.rs

+//! Contract constructor call builder.
+use {Param, Result, ErrorKind, Token, ParamType, encode, Bytes};
+
+/// Contract constructor specification.
+#[derive(Debug, Clone, PartialEq, Deserialize)]
+pub struct Constructor {
+	/// Constructor input.
+	pub inputs: Vec<Param>,
+}
+
+impl Constructor {
+	/// Returns all input params of given constructor.
+	fn param_types(&self) -> Vec<ParamType> {
+		self.inputs.iter()
+			.map(|p| p.kind.clone())
+			.collect()
+	}
+
+	/// Prepares ABI constructor call with given input params.
+	pub fn encode_input(&self, code: Bytes, tokens: &[Token]) -> Result<Bytes> {
+		let params = self.param_types();
+
+		if Token::types_check(tokens, &params) {
+			Ok(code.into_iter().chain(encode(tokens)).collect())
+		} else {
+			Err(ErrorKind::InvalidData.into())
+		}
+	}
+}

libs/ethabi/src/contract.rs

+use std::{io, fmt};
+use std::collections::HashMap;
+use std::collections::hash_map::Values;
+use std::iter::Flatten;
+use serde::{Deserialize, Deserializer};
+use serde::de::{Visitor, SeqAccess};
+use serde_json;
+use operation::Operation;
+use {errors, ErrorKind, Event, Constructor, Function, ParamType};
+use signature::short_signature;
+
+/// API building calls to contracts ABI.
+#[derive(Clone, Debug, PartialEq)]
+pub struct Contract {
+    /// Contract constructor.
+    pub constructor: Option<Constructor>,
+    /// Contract functions.
+    pub functions: HashMap<String, Function>,
+    /// Contract events, maps signature to event.
+    pub events: HashMap<String, Vec<Event>>,
+    /// Contract has fallback function.
+    pub fallback: bool,
+    /// add by echo : sig -> functions.key
+    pub signers: HashMap<Vec<u8>, String>,
+}
+
+impl<'a> Deserialize<'a> for Contract {
+    fn deserialize<D>(deserializer: D) -> Result<Contract, D::Error> where D: Deserializer<'a> {
+        deserializer.deserialize_any(ContractVisitor)
+    }
+}
+
+struct ContractVisitor;
+
+impl<'a> Visitor<'a> for ContractVisitor {
+    type Value = Contract;
+
+    fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+        formatter.write_str("valid abi spec file")
+    }
+
+    fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error> where A: SeqAccess<'a> {
+        let mut result = Contract {
+            constructor: None,
+            functions: HashMap::default(),
+            events: HashMap::default(),
+            fallback: false,
+            signers: HashMap::default(),
+        };
+
+        while let Some(operation) = seq.next_element()? {
+            match operation {
+                Operation::Constructor(constructor) => {
+                    result.constructor = Some(constructor);
+                }
+                Operation::Function(func) => {
+                    result.functions.insert(func.name.clone(), func);
+                }
+                Operation::Event(event) => {
+                    result.events.entry(event.name.clone()).or_default().push(event);
+                }
+                Operation::Fallback => {
+                    result.fallback = true;
+                }
+            }
+        }
+
+        Ok(result)
+    }
+}
+
+impl Contract {
+    /*
+    /// Loads contract from json.
+    pub fn load<T: io::Read>(reader: T) -> errors::Result<Self> {
+        let c = serde_json::from_reader(reader).map_err(From::from);
+        return c;
+    }*/
+
+    /// Creates constructor call builder.
+    pub fn constructor(&self) -> Option<&Constructor> {
+        self.constructor.as_ref()
+    }
+
+    /// Creates function call builder.
+    pub fn function(&self, name: &str) -> errors::Result<&Function> {
+        self.functions.get(name).ok_or_else(|| ErrorKind::InvalidName(name.to_owned()).into())
+    }
+
+    /// Get the contract event named `name`, the first if there are multiple.
+    pub fn event(&self, name: &str) -> errors::Result<&Event> {
+        self.events.get(name).into_iter()
+            .flatten()
+            .next()
+            .ok_or_else(|| ErrorKind::InvalidName(name.to_owned()).into())
+    }
+
+    /// Get all contract events named `name`.
+    pub fn events_by_name(&self, name: &str) -> errors::Result<&Vec<Event>> {
+        self.events.get(name)
+            .ok_or_else(|| ErrorKind::InvalidName(name.to_owned()).into())
+    }
+
+    /// Iterate over all functions of the contract in arbitrary order.
+    pub fn functions(&self) -> Functions {
+        Functions(self.functions.values())
+    }
+
+    /// Iterate over all events of the contract in arbitrary order.
+    pub fn events(&self) -> Events {
+        Events(self.events.values().flatten())
+    }
+
+    /// Returns true if contract has fallback
+    pub fn fallback(&self) -> bool {
+        self.fallback
+    }
+
+    /// add by echo : 初始化函数签名 map
+    pub fn function_by_sig(&mut self, sig: &Vec<u8>) -> errors::Result<&Function> {
+        if self.signers.len() == 0 {
+            self.signers = self.functions.iter().map(|(n, f)| {
+                let params: Vec<ParamType> = f.inputs.iter().map(|p| p.kind.clone()).collect();
+                let signed = short_signature(n, &params).to_vec();
+                (signed.clone(), n.clone())
+            }).collect();
+        }
+        let name = self.signers.get(sig).ok_or_else(|| ErrorKind::InvalidData)?;
+        self.function(name)
+    }
+}
+
+/// Contract functions interator.
+pub struct Functions<'a>(Values<'a, String, Function>);
+
+impl<'a> Iterator for Functions<'a> {
+    type Item = &'a Function;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        self.0.next()
+    }
+}
+
+/// Contract events interator.
+pub struct Events<'a>(Flatten<Values<'a, String, Vec<Event>>>);
+
+impl<'a> Iterator for Events<'a> {
+    type Item = &'a Event;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        self.0.next()
+    }
+}

libs/ethabi/src/decoder.rs

+//! ABI decoder.
+
+use util::slice_data;
+use {Word, Token, ErrorKind, Error, ResultExt, ParamType};
+
+struct DecodeResult {
+	token: Token,
+	new_offset: usize,
+}
+
+struct BytesTaken {
+	bytes: Vec<u8>,
+	new_offset: usize,
+}
+
+fn as_u32(slice: &Word) -> Result<u32, Error> {
+	if !slice[..28].iter().all(|x| *x == 0) {
+		return Err(ErrorKind::InvalidData.into());
+	}
+
+	let result = ((slice[28] as u32) << 24) +
+		((slice[29] as u32) << 16) +
+		((slice[30] as u32) << 8) +
+		(slice[31] as u32);
+
+	Ok(result)
+}
+
+fn as_bool(slice: &Word) -> Result<bool, Error> {
+	if !slice[..31].iter().all(|x| *x == 0) {
+		return Err(ErrorKind::InvalidData.into());
+	}
+
+	Ok(slice[31] == 1)
+}
+
+/// Decodes ABI compliant vector of bytes into vector of tokens described by types param.
+pub fn decode(types: &[ParamType], data: &[u8]) -> Result<Vec<Token>, Error> {
+    let is_empty_bytes_valid_encoding = types.iter().all(|t| t.is_empty_bytes_valid_encoding());
+    if !is_empty_bytes_valid_encoding && data.is_empty() {
+        bail!("please ensure the contract and method you're calling exist! failed to decode empty bytes. if you're using jsonrpc this is likely due to jsonrpc returning `0x` in case contract or method don't exist");
+    }
+	let slices = slice_data(data)?;
+	let mut tokens = Vec::with_capacity(types.len());
+	let mut offset = 0;
+	for param in types {
+		let res = decode_param(param, &slices, offset).chain_err(|| format!("Cannot decode {}", param))?;
+		offset = res.new_offset;
+		tokens.push(res.token);
+	}
+	Ok(tokens)
+}
+
+fn peek(slices: &[Word], position: usize) -> Result<&Word, Error> {
+	slices.get(position).ok_or_else(|| ErrorKind::InvalidData.into())
+}
+
+fn take_bytes(slices: &[Word], position: usize, len: usize) -> Result<BytesTaken, Error> {
+	let slices_len = (len + 31) / 32;
+
+	let mut bytes_slices = Vec::with_capacity(slices_len);
+	for i in 0..slices_len {
+		let slice = try!(peek(slices, position + i));
+		bytes_slices.push(slice);
+	}
+
+	let bytes = bytes_slices.into_iter()
+		.flat_map(|slice| slice.to_vec())
+		.take(len)
+		.collect();
+
+	let taken = BytesTaken {
+		bytes,
+		new_offset: position + slices_len,
+	};
+
+	Ok(taken)
+}
+
+fn decode_param(param: &ParamType, slices: &[Word], offset: usize) -> Result<DecodeResult, Error> {
+	match *param {
+		ParamType::Address => {
+			let slice = try!(peek(slices, offset));
+			let mut address = [0u8; 20];
+			address.copy_from_slice(&slice[12..]);
+
+			let result = DecodeResult {
+				token: Token::Address(address.into()),
+				new_offset: offset + 1,
+			};
+
+			Ok(result)
+		},
+		ParamType::Int(_) => {
+			let slice = try!(peek(slices, offset));
+
+			let result = DecodeResult {
+				token: Token::Int(slice.clone().into()),
+				new_offset: offset + 1,
+			};
+
+			Ok(result)
+		},
+		ParamType::Uint(_) => {
+			let slice = try!(peek(slices, offset));
+
+			let result = DecodeResult {
+				token: Token::Uint(slice.clone().into()),
+				new_offset: offset + 1,
+			};
+
+			Ok(result)
+		},
+		ParamType::Bool => {
+			let slice = try!(peek(slices, offset));
+
+			let b = try!(as_bool(slice));
+
+			let result = DecodeResult {
+				token: Token::Bool(b),
+				new_offset: offset + 1,
+			};
+
+			Ok(result)
+		},
+		ParamType::FixedBytes(len) => {
+			let taken = try!(take_bytes(slices, offset, len));
+
+			let result = DecodeResult {
+				token: Token::FixedBytes(taken.bytes),
+				new_offset: taken.new_offset,
+			};
+
+			Ok(result)
+		},
+		ParamType::Bytes => {
+			let offset_slice = try!(peek(slices, offset));
+			let len_offset = (try!(as_u32(offset_slice)) / 32) as usize;
+
+			let len_slice = try!(peek(slices, len_offset));
+			let len = try!(as_u32(len_slice)) as usize;
+
+			let taken = try!(take_bytes(slices, len_offset + 1, len));
+
+			let result = DecodeResult {
+				token: Token::Bytes(taken.bytes),
+				new_offset: offset + 1,
+			};
+
+			Ok(result)
+		},
+		ParamType::String => {
+			let offset_slice = try!(peek(slices, offset));
+			let len_offset = (try!(as_u32(offset_slice)) / 32) as usize;
+
+			let len_slice = try!(peek(slices, len_offset));
+			let len = try!(as_u32(len_slice)) as usize;
+
+			let taken = try!(take_bytes(slices, len_offset + 1, len));
+
+			let result = DecodeResult {
+				token: Token::String(try!(String::from_utf8(taken.bytes))),
+				new_offset: offset + 1,
+			};
+
+			Ok(result)
+		},
+		ParamType::Array(ref t) => {
+			let offset_slice = try!(peek(slices, offset));
+			let len_offset = (try!(as_u32(offset_slice)) / 32) as usize;
+
+			let len_slice = try!(peek(slices, len_offset));
+			let len = try!(as_u32(len_slice)) as usize;
+
+			let sub_slices = &slices[len_offset + 1..];
+			let mut tokens = Vec::with_capacity(len);
+			let mut new_offset = 0;
+			for _ in 0..len {
+				let res = try!(decode_param(t, &sub_slices, new_offset));
+				new_offset = res.new_offset;
+				tokens.push(res.token);
+			}
+
+			let result = DecodeResult {
+				token: Token::Array(tokens),
+				new_offset: offset + 1,
+			};
+
+			Ok(result)
+		},
+		ParamType::FixedArray(ref t, len) => {
+			let mut tokens = Vec::with_capacity(len);
+			let new_offset = if param.is_dynamic() {
+				let offset_slice = peek(slices, offset)?;
+				let tail_offset = (as_u32(offset_slice)? / 32) as usize;
+				let slices = &slices[tail_offset..];
+				let mut new_offset = 0;
+
+				for _ in 0..len {
+					let res = decode_param(t, &slices, new_offset)?;
+					new_offset = res.new_offset;
+					tokens.push(res.token);
+				}
+				offset + 1
+			} else {
+				let mut new_offset = offset;
+
+				for _ in 0..len {
+					let res = decode_param(t, &slices, new_offset)?;
+					new_offset = res.new_offset;
+					tokens.push(res.token);
+				}
+				new_offset
+			};
+
+			let result = DecodeResult {
+				token: Token::FixedArray(tokens),
+				new_offset,
+			};
+
+			Ok(result)
+		}
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use {decode, ParamType};
+
+	#[test]
+	fn decode_from_empty_byte_slice() {
+        // these can NOT be decoded from empty byte slice
+        assert!(decode(&[ParamType::Address], &[]).is_err());
+        assert!(decode(&[ParamType::Bytes], &[]).is_err());
+        assert!(decode(&[ParamType::Int(0)], &[]).is_err());
+        assert!(decode(&[ParamType::Int(1)], &[]).is_err());
+        assert!(decode(&[ParamType::Int(0)], &[]).is_err());
+        assert!(decode(&[ParamType::Int(1)], &[]).is_err());
+        assert!(decode(&[ParamType::Bool], &[]).is_err());
+        assert!(decode(&[ParamType::String], &[]).is_err());
+        assert!(decode(&[ParamType::Array(Box::new(ParamType::Bool))], &[]).is_err());
+        assert!(decode(&[ParamType::FixedBytes(1)], &[]).is_err());
+        assert!(decode(&[ParamType::FixedArray(Box::new(ParamType::Bool), 1)], &[]).is_err());
+
+        // these are the only ones that can be decoded from empty byte slice
+        assert!(decode(&[ParamType::FixedBytes(0)], &[]).is_ok());
+        assert!(decode(&[ParamType::FixedArray(Box::new(ParamType::Bool), 0)], &[]).is_ok());
+	}
+}
+

libs/ethabi/src/encoder.rs

+//! ABI encoder.
+
+use util::pad_u32;
+use {Word, Token, Bytes};
+
+fn pad_bytes(bytes: &[u8]) -> Vec<Word> {
+	let mut result = vec![pad_u32(bytes.len() as u32)];
+	result.extend(pad_fixed_bytes(bytes));
+	result
+}
+
+fn pad_fixed_bytes(bytes: &[u8]) -> Vec<Word> {
+	let len = (bytes.len() + 31) / 32;
+	let mut result = Vec::with_capacity(len);
+	for i in 0..len {
+		let mut padded = [0u8; 32];
+
+		let to_copy = match i == len - 1 {
+			false => 32,
+			true => match bytes.len() % 32 {
+				0 => 32,
+				x => x,
+			},
+		};
+
+		let offset = 32 * i;
+		padded[..to_copy].copy_from_slice(&bytes[offset..offset + to_copy]);
+		result.push(padded);
+	}
+
+	result
+}
+
+#[derive(Debug)]
+enum Mediate {
+	Raw(Vec<Word>),
+	Prefixed(Vec<Word>),
+	PrefixedArray(Vec<Mediate>),
+	PrefixedArrayWithLength(Vec<Mediate>),
+}
+
+impl Mediate {
+	fn head_len(&self) -> u32 {
+		match *self {
+			Mediate::Raw(ref raw) => 32 * raw.len() as u32,
+			Mediate::Prefixed(_) | Mediate::PrefixedArray(_) | Mediate::PrefixedArrayWithLength(_) => 32,
+		}
+	}
+
+	fn tail_len(&self) -> u32 {
+		match *self {
+			Mediate::Raw(_) => 0,
+			Mediate::Prefixed(ref pre) => pre.len() as u32 * 32,
+			Mediate::PrefixedArray(ref mediates) => mediates.iter().fold(0, |acc, m| acc + m.head_len() + m.tail_len()),
+			Mediate::PrefixedArrayWithLength(ref mediates) => mediates.iter().fold(32, |acc, m| acc + m.head_len() + m.tail_len()),
+		}
+	}
+
+	fn head(&self, suffix_offset: u32) -> Vec<Word> {
+		match *self {
+			Mediate::Raw(ref raw) => raw.clone(),
+			Mediate::Prefixed(_) | Mediate::PrefixedArray(_) | Mediate::PrefixedArrayWithLength(_) => {
+				vec![pad_u32(suffix_offset)]
+			}
+		}
+	}
+
+	fn tail(&self) -> Vec<Word> {
+		match *self {
+			Mediate::Raw(_) => vec![],
+			Mediate::Prefixed(ref raw) => raw.clone(),
+			Mediate::PrefixedArray(ref mediates) => encode_head_tail(mediates),
+			Mediate::PrefixedArrayWithLength(ref mediates) => {
+				// + 32 added to offset represents len of the array prepanded to tail
+				let mut result = vec![pad_u32(mediates.len() as u32)];
+
+				let head_tail = encode_head_tail(mediates);
+
+				result.extend(head_tail);
+				result
+			},
+		}
+	}
+}
+
+fn encode_head_tail(mediates: &Vec<Mediate>) -> Vec<Word> {
+	let heads_len = mediates.iter()
+		.fold(0, |acc, m| acc + m.head_len());
+
+	let (mut result, len) = mediates.iter()
+		.fold(
+			(Vec::with_capacity(heads_len as usize), heads_len),
+			|(mut acc, offset), m| {
+				acc.extend(m.head(offset));
+				(acc, offset + m.tail_len())
+			}
+		);
+
+	let tails = mediates.iter()
+		.fold(
+			Vec::with_capacity((len - heads_len) as usize),
+			|mut acc, m| {
+				acc.extend(m.tail());
+				acc
+			}
+		);
+
+	result.extend(tails);
+	result
+}
+
+/// Encodes vector of tokens into ABI compliant vector of bytes.
+pub fn encode(tokens: &[Token]) -> Bytes {
+	let mediates = &tokens.iter()
+		.map(encode_token)
+		.collect();
+
+	encode_head_tail(mediates).iter()
+		.flat_map(|word| word.to_vec())
+		.collect()
+}
+
+fn encode_token(token: &Token) -> Mediate {
+	match *token {
+		Token::Address(ref address) => {
+			let mut padded = [0u8; 32];
+			padded[12..].copy_from_slice(address.as_ref());
+			Mediate::Raw(vec![padded])
+		},
+		Token::Bytes(ref bytes) => Mediate::Prefixed(pad_bytes(bytes)),
+		Token::String(ref s) => Mediate::Prefixed(pad_bytes(s.as_bytes())),
+		Token::FixedBytes(ref bytes) => Mediate::Raw(pad_fixed_bytes(bytes)),
+		Token::Int(int) => Mediate::Raw(vec![int.into()]),
+		Token::Uint(uint) => Mediate::Raw(vec![uint.into()]),
+		Token::Bool(b) => {
+			let mut value = [0u8; 32];
+			if b {
+				value[31] = 1;
+			}
+			Mediate::Raw(vec![value])
+		},
+		Token::Array(ref tokens) => {
+			let mediates = tokens.iter()
+				.map(encode_token)
+				.collect();
+
+			Mediate::PrefixedArrayWithLength(mediates)
+		},
+		Token::FixedArray(ref tokens) => {
+			let mediates = tokens.iter()
+				.map(encode_token)
+				.collect();
+
+			if token.is_dynamic() {
+				Mediate::PrefixedArray(mediates)
+			} else {
+				Mediate::Raw(encode_head_tail(&mediates))
+			}
+		},
+	}
+}
+

libs/ethabi/src/errors.rs

+#![allow(unknown_lints)]
+#![allow(missing_docs)]
+
+use std::{num, string};
+use {serde_json, hex};
+
+error_chain! {
+	foreign_links {
+		SerdeJson(serde_json::Error);
+		ParseInt(num::ParseIntError);
+		Utf8(string::FromUtf8Error);
+		Hex(hex::FromHexError);
+	}
+
+	errors {
+		InvalidName(name: String) {
+			description("Invalid name"),
+			display("Invalid name `{}`", name),
+		}
+
+		InvalidData {
+			description("Invalid data"),
+			display("Invalid data"),
+		}
+	}
+}

libs/ethabi/src/event.rs

+//! Contract event.
+
+use std::collections::HashMap;
+use tiny_keccak::keccak256;
+use signature::long_signature;
+use {
+	Log, Hash, RawLog, LogParam, RawTopicFilter, TopicFilter,
+	Topic, ParamType, EventParam, encode, decode, Token,
+	Result, ErrorKind
+};
+
+/// Contract event.
+#[derive(Clone, Debug, PartialEq, Deserialize)]
+pub struct Event {
+	/// Event name.
+	pub name: String,
+	/// Event input.
+	pub inputs: Vec<EventParam>,
+	/// If anonymous, event cannot be found using `from` filter.
+	pub anonymous: bool,
+}
+
+impl Event {
+	/// Returns names of all params.
+	fn params_names(&self) -> Vec<String> {
+		self.inputs.iter()
+			.map(|p| p.name.clone())
+			.collect()
+	}
+
+	/// Returns types of all params.
+	fn param_types(&self) -> Vec<ParamType> {
+		self.inputs.iter()
+			.map(|p| p.kind.clone())
+			.collect()
+	}
+
+	/// Returns all params of the event.
+	fn indexed_params(&self, indexed: bool) -> Vec<EventParam> {
+		self.inputs.iter()
+			.filter(|p| p.indexed == indexed)
+			.cloned()
+			.collect()
+	}
+
+	/// Event signature
+	pub fn signature(&self) -> Hash {
+		long_signature(&self.name, &self.param_types())
+	}
+
+	/// Creates topic filter
+	pub fn filter(&self, raw: RawTopicFilter) -> Result<TopicFilter> {
+		fn convert_token(token: Token, kind: &ParamType) -> Result<Hash> {
+			if !token.type_check(kind) {
+				return Err(ErrorKind::InvalidData.into());
+			}
+			let encoded = encode(&[token]);
+			if encoded.len() == 32 {
+				let mut data = [0u8; 32];
+				data.copy_from_slice(&encoded);
+				Ok(data.into())
+			} else {
+				Ok(keccak256(&encoded).into())
+			}
+		}
+
+		fn convert_topic(topic: Topic<Token>, kind: Option<&ParamType>) -> Result<Topic<Hash>> {
+			match topic {
+				Topic::Any => Ok(Topic::Any),
+				Topic::OneOf(tokens) => match kind {
+					None => Err(ErrorKind::InvalidData.into()),
+					Some(kind) => {
+						let topics = tokens.into_iter()
+							.map(|token| convert_token(token, kind))
+							.collect::<Result<Vec<_>>>()?;
+						Ok(Topic::OneOf(topics))
+					}
+				},
+				Topic::This(token) => match kind {
+					None => Err(ErrorKind::InvalidData.into()),
+					Some(kind) => Ok(Topic::This(convert_token(token, kind)?)),
+				}
+			}
+		}
+
+		let kinds: Vec<_> = self.indexed_params(true).into_iter().map(|param| param.kind).collect();
+		let result = if self.anonymous {
+			TopicFilter {
+				topic0: convert_topic(raw.topic0, kinds.get(0))?,
+				topic1: convert_topic(raw.topic1, kinds.get(1))?,
+				topic2: convert_topic(raw.topic2, kinds.get(2))?,
+				topic3: Topic::Any,
+			}
+		} else {
+			TopicFilter {
+				topic0: Topic::This(self.signature()),
+				topic1: convert_topic(raw.topic0, kinds.get(0))?,
+				topic2: convert_topic(raw.topic1, kinds.get(1))?,
+				topic3: convert_topic(raw.topic2, kinds.get(2))?,
+			}
+		};
+
+		Ok(result)
+	}
+
+	// Converts param types for indexed parameters to bytes32 where appropriate
+	// This applies to strings, arrays and bytes to follow the encoding of
+	// these indexed param types according to
+	// https://solidity.readthedocs.io/en/develop/abi-spec.html#encoding-of-indexed-event-parameters
+	fn convert_topic_param_type(&self, kind: &ParamType) -> ParamType {
+		match kind {
+			ParamType::String
+			| ParamType::Bytes
+			| ParamType::Array(_)
+			| ParamType::FixedArray(_, _) => ParamType::FixedBytes(32),
+			_ => kind.clone()
+		}
+	}
+
+	/// Parses `RawLog` and retrieves all log params from it.
+	pub fn parse_log(&self, log: RawLog) -> Result<Log> {
+		let topics = log.topics;
+		let data = log.data;
+		let topics_len = topics.len();
+		// obtains all params info
+		let topic_params = self.indexed_params(true);
+		let data_params = self.indexed_params(false);
+		// then take first topic if event is not anonymous
+		let to_skip = if self.anonymous {
+			0
+		} else {
+			// verify
+			let event_signature = topics.get(0).ok_or(ErrorKind::InvalidData)?;
+			if event_signature != &self.signature() {
+				return Err(ErrorKind::InvalidData.into());
+			}
+			1
+		};
+
+		let topic_types = topic_params.iter()
+			.map(|p| self.convert_topic_param_type(&p.kind))
+			.collect::<Vec<ParamType>>();
+
+		let flat_topics = topics.into_iter()
+			.skip(to_skip)
+			.flat_map(|t| t.as_ref().to_vec())
+			.collect::<Vec<u8>>();
+
+		let topic_tokens = try!(decode(&topic_types, &flat_topics));
+
+		// topic may be only a 32 bytes encoded token
+		if topic_tokens.len() != topics_len - to_skip {
+			return Err(ErrorKind::InvalidData.into());
+		}
+
+		let topics_named_tokens = topic_params.into_iter()
+			.map(|p| p.name)
+			.zip(topic_tokens.into_iter());
+
+		let data_types = data_params.iter()
+			.map(|p| p.kind.clone())
+			.collect::<Vec<ParamType>>();
+
+		let data_tokens = try!(decode(&data_types, &data));
+
+		let data_named_tokens = data_params.into_iter()
+			.map(|p| p.name)
+			.zip(data_tokens.into_iter());
+
+		let named_tokens = topics_named_tokens
+			.chain(data_named_tokens)
+			.collect::<HashMap<String, Token>>();
+
+		let decoded_params = self.params_names()
+			.into_iter()
+			.map(|name| LogParam {
+				name: name.clone(),
+				value: named_tokens[&name].clone()
+			})
+			.collect();
+
+		let result = Log {
+			params: decoded_params,
+		};
+
+		Ok(result)
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use hex::FromHex;
+	use token::Token;
+	use signature::long_signature;
+	use log::{RawLog, Log};
+	use {EventParam, ParamType, Event, LogParam};
+
+	#[test]
+	fn test_decoding_event() {
+		let event = Event {
+			name: "foo".to_owned(),
+			inputs: vec![EventParam {
+				name: "a".to_owned(),
+				kind: ParamType::Int(256),
+				indexed: false,
+			}, EventParam {
+				name: "b".to_owned(),
+				kind: ParamType::Int(256),
+				indexed: true,
+			}, EventParam {
+				name: "c".to_owned(),
+				kind: ParamType::Address,
+				indexed: false,
+			}, EventParam {
+				name: "d".to_owned(),
+				kind: ParamType::Address,
+				indexed: true,
+			}, EventParam {
+				name: "e".to_owned(),
+				kind: ParamType::String,
+				indexed: true,
+			}, EventParam {
+				name: "f".to_owned(),
+				kind: ParamType::Array(Box::new(ParamType::Int(256))),
+				indexed: true
+			}, EventParam {
+				name: "g".to_owned(),
+				kind: ParamType::FixedArray(Box::new(ParamType::Address), 5),
+				indexed: true,
+			}],
+			anonymous: false,
+		};
+
+		let log = RawLog {
+			topics: vec![
+				long_signature("foo", &[
+					ParamType::Int(256),
+					ParamType::Int(256),
+					ParamType::Address,
+					ParamType::Address,
+					ParamType::String,
+					ParamType::Array(Box::new(ParamType::Int(256))),
+					ParamType::FixedArray(Box::new(ParamType::Address), 5),
+				]),
+				"0000000000000000000000000000000000000000000000000000000000000002".parse().unwrap(),
+				"0000000000000000000000001111111111111111111111111111111111111111".parse().unwrap(),
+				"00000000000000000aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa".parse().unwrap(),
+				"00000000000000000bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb".parse().unwrap(),
+				"00000000000000000ccccccccccccccccccccccccccccccccccccccccccccccc".parse().unwrap(),
+			],
+			data:
+			("".to_owned() +
+				"0000000000000000000000000000000000000000000000000000000000000003" +
+				"0000000000000000000000002222222222222222222222222222222222222222").from_hex().unwrap()
+		};
+		let result = event.parse_log(log).unwrap();
+
+		assert_eq!(result, Log { params: vec![
+			("a".to_owned(), Token::Int("0000000000000000000000000000000000000000000000000000000000000003".into())),
+			("b".to_owned(), Token::Int("0000000000000000000000000000000000000000000000000000000000000002".into())),
+			("c".to_owned(), Token::Address("2222222222222222222222222222222222222222".parse().unwrap())),
+			("d".to_owned(), Token::Address("1111111111111111111111111111111111111111".parse().unwrap())),
+			("e".to_owned(), Token::FixedBytes("00000000000000000aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa".from_hex().unwrap())),
+			("f".to_owned(), Token::FixedBytes("00000000000000000bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb".from_hex().unwrap())),
+			("g".to_owned(), Token::FixedBytes("00000000000000000ccccccccccccccccccccccccccccccccccccccccccccccc".from_hex().unwrap())),
+		].into_iter().map(|(name, value)| LogParam { name, value }).collect::<Vec<_>>()});
+	}
+}

libs/ethabi/src/event_param.rs

+//! Event param specification.
+
+use {ParamType};
+
+/// Event param specification.
+#[derive(Debug, Clone, PartialEq, Deserialize)]
+pub struct EventParam {
+	/// Param name.
+	pub name: String,
+	/// Param type.
+	#[serde(rename="type")]
+	pub kind: ParamType,
+	/// Indexed flag. If true, param is used to build block bloom.
+	pub indexed: bool,
+}
+
+#[cfg(test)]
+mod tests {
+	use serde_json;
+	use {EventParam, ParamType};
+
+	#[test]
+	fn event_param_deserialization() {
+		let s = r#"{
+			"name": "foo",
+			"type": "address",
+			"indexed": true
+		}"#;
+
+		let deserialized: EventParam = serde_json::from_str(s).unwrap();
+
+		assert_eq!(deserialized, EventParam {
+			name: "foo".to_owned(),
+			kind: ParamType::Address,
+			indexed: true,
+		});
+	}
+}

libs/ethabi/src/filter.rs

+use std::ops;
+use serde::{Serialize, Serializer};
+use serde_json::Value;
+use {Hash, Token};
+
+/// Raw topic filter.
+#[derive(Debug, PartialEq, Default)]
+pub struct RawTopicFilter {
+	/// Topic.
+	pub topic0: Topic<Token>,
+	/// Topic.
+	pub topic1: Topic<Token>,
+	/// Topic.
+	pub topic2: Topic<Token>,
+}
+
+/// Topic filter.
+#[derive(Debug, PartialEq, Default)]
+pub struct TopicFilter {
+	/// Usually (for not-anonymous transactions) the first topic is event signature.
+	pub topic0: Topic<Hash>,
+	/// Second topic.
+	pub topic1: Topic<Hash>,
+	/// Third topic.
+	pub topic2: Topic<Hash>,
+	/// Fourth topic.
+	pub topic3: Topic<Hash>,
+}
+
+impl Serialize for TopicFilter {
+	fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+	where S: Serializer {
+		vec![&self.topic0, &self.topic1, &self.topic2, &self.topic3].serialize(serializer)
+	}
+}
+
+/// Acceptable topic possibilities.
+#[derive(Debug, PartialEq)]
+pub enum Topic<T> {
+	/// Match any.
+	Any,
+	/// Match any of the hashes.
+	OneOf(Vec<T>),
+	/// Match only this hash.
+	This(T),
+}
+
+impl<T> Topic<T> {
+	/// Map
+	pub fn map<F, O>(self, f: F) -> Topic<O> where F: Fn(T) -> O {
+		match self {
+			Topic::Any => Topic::Any,
+			Topic::OneOf(topics) => Topic::OneOf(topics.into_iter().map(f).collect()),
+			Topic::This(topic) => Topic::This(f(topic)),
+		}
+	}
+
+	/// Returns true if topic is empty (Topic::Any)
+	pub fn is_any(&self) -> bool {
+		match *self {
+			Topic::Any => true,
+			Topic::This(_) | Topic::OneOf(_) => false,
+		}
+	}
+}
+
+impl<T> Default for Topic<T> {
+	fn default() -> Self {
+		Topic::Any
+	}
+}
+
+impl<T> From<Option<T>> for Topic<T> {
+	fn from(o: Option<T>) -> Self {
+		match o {
+			Some(topic) => Topic::This(topic),
+			None => Topic::Any,
+		}
+	}
+}
+
+impl<T> From<T> for Topic<T> {
+	fn from(topic: T) -> Self {
+		Topic::This(topic)
+	}
+}
+
+impl<T> From<Vec<T>> for Topic<T> {
+	fn from(topics: Vec<T>) -> Self {
+		Topic::OneOf(topics)
+	}
+}
+
+impl<T> Into<Vec<T>> for Topic<T> {
+	fn into(self: Self) -> Vec<T> {
+		match self {
+			Topic::Any => vec![],
+			Topic::This(topic) => vec![topic],
+			Topic::OneOf(topics) => topics,
+		}
+	}
+}
+
+impl Serialize for Topic<Hash> {
+	fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+	where S: Serializer {
+		let value = match *self {
+			Topic::Any => Value::Null,
+			Topic::OneOf(ref vec) => {
+				let v = vec.iter()
+					.map(|h| format!("0x{:x}", h))
+					.map(Value::String)
+					.collect();
+				Value::Array(v)
+			},
+			Topic::This(ref hash) => Value::String(format!("0x{:x}", hash)),
+		};
+		value.serialize(serializer)
+	}
+}
+
+impl<T> ops::Index<usize> for Topic<T> {
+	type Output = T;
+
+	fn index(&self, index: usize) -> &Self::Output {
+		match *self {
+			Topic::Any => panic!("Topic unavailable"),
+			Topic::This(ref topic) => {
+				if index != 0 {
+					panic!("Topic unavailable");
+				}
+				topic
+			},
+			Topic::OneOf(ref topics) => topics.index(index),
+		}
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use serde_json;
+	use super::{Topic, TopicFilter};
+	use Hash;
+
+	fn hash(s: &'static str) -> Hash {
+		s.parse().unwrap()
+	}
+
+	#[test]
+	fn test_topic_filter_serialization() {
+		let expected =
+r#"["0x000000000000000000000000a94f5374fce5edbc8e2a8697c15331677e6ebf0b",null,["0x000000000000000000000000a94f5374fce5edbc8e2a8697c15331677e6ebf0b","0x0000000000000000000000000aff3454fce5edbc8cca8697c15331677e6ebccc"],null]"#;
+
+		let topic = TopicFilter {
+			topic0: Topic::This(hash("000000000000000000000000a94f5374fce5edbc8e2a8697c15331677e6ebf0b")),
+			topic1: Topic::Any,
+			topic2: Topic::OneOf(vec![hash("000000000000000000000000a94f5374fce5edbc8e2a8697c15331677e6ebf0b"), hash("0000000000000000000000000aff3454fce5edbc8cca8697c15331677e6ebccc")]),
+			topic3: Topic::Any,
+		};
+
+		let topic_str = serde_json::to_string(&topic).unwrap();
+		assert_eq!(expected, &topic_str);
+	}
+
+	#[test]
+	fn test_topic_from() {
+		assert_eq!(Topic::Any as Topic<u64>, None.into());
+		assert_eq!(Topic::This(10u64), 10u64.into());
+		assert_eq!(Topic::OneOf(vec![10u64, 20]), vec![10u64, 20].into());
+	}
+
+	#[test]
+	fn test_topic_into_vec() {
+		let expected: Vec<u64> = vec![];
+		let is: Vec<u64> = (Topic::Any as Topic<u64>).into();
+		assert_eq!(expected, is);
+		let expected: Vec<u64> = vec![10];
+		let is: Vec<u64> = Topic::This(10u64).into();
+		assert_eq!(expected, is);
+		let expected: Vec<u64> = vec![10, 20];
+		let is: Vec<u64> = Topic::OneOf(vec![10u64, 20]).into();
+		assert_eq!(expected, is);
+	}
+
+	#[test]
+	fn test_topic_is_any() {
+		assert!((Topic::Any as Topic<u8>).is_any());
+		assert!(!Topic::OneOf(vec![10u64, 20]).is_any());
+		assert!(!Topic::This(10u64).is_any());
+	}
+
+	#[test]
+	fn test_topic_index() {
+		assert_eq!(Topic::OneOf(vec![10u64, 20])[0], 10);
+		assert_eq!(Topic::OneOf(vec![10u64, 20])[1], 20);
+		assert_eq!(Topic::This(10u64)[0], 10);
+	}
+
+	#[test]
+	#[should_panic(expected = "Topic unavailable")]
+	fn test_topic_index_panic() {
+		let _ = (Topic::Any as Topic<u8>)[0];
+	}
+
+	#[test]
+	#[should_panic(expected = "Topic unavailable")]
+	fn test_topic_index_panic2() {
+		assert_eq!(Topic::This(10u64)[1], 10);
+	}
+}

libs/ethabi/src/function.rs

+//! Contract function call builder.
+
+use signature::short_signature;
+use {Param, Token, Result, ErrorKind, Bytes, decode, ParamType, encode};
+
+/// Contract function specification.
+#[derive(Debug, Clone, PartialEq, Deserialize)]
+pub struct Function {
+    /// Function name.
+    pub name: String,
+    /// Function input.
+    pub inputs: Vec<Param>,
+    /// Function output.
+    pub outputs: Vec<Param>,
+    /// Constant function.
+    #[serde(default)]
+    pub constant: bool,
+}
+
+impl Function {
+    /// Returns all input params of given function.
+    fn input_param_types(&self) -> Vec<ParamType> {
+        self.inputs.iter()
+            .map(|p| p.kind.clone())
+            .collect()
+    }
+
+    /// Returns all output params of given function.
+    fn output_param_types(&self) -> Vec<ParamType> {
+        self.outputs.iter()
+            .map(|p| p.kind.clone())
+            .collect()
+    }
+
+    /// Prepares ABI function call with given input params.
+    pub fn encode_input(&self, tokens: &[Token]) -> Result<Bytes> {
+        let params = self.input_param_types();
+
+        if !Token::types_check(tokens, &params) {
+            return Err(ErrorKind::InvalidData.into());
+        }
+
+        let signed = short_signature(&self.name, &params).to_vec();
+        let encoded = encode(tokens);
+        Ok(signed.into_iter().chain(encoded.into_iter()).collect())
+    }
+
+    /// Parses the ABI function output to list of tokens.
+    pub fn decode_output(&self, data: &[u8]) -> Result<Vec<Token>> {
+        decode(&self.output_param_types(), &data)
+    }
+
+    /// add by echo : 编写 wasm 合约时用来序列化返回值
+    pub fn encode_output(&self, tokens: &[Token]) -> Result<Bytes> {
+        let params = self.output_param_types();
+
+        if !Token::types_check(tokens, &params) {
+            return Err(ErrorKind::InvalidData.into());
+        }
+
+        let encoded = encode(tokens);
+        Ok(encoded.into_iter().collect())
+    }
+
+    /// add by echo : 编写 wasm 合约时用来反序列化输入参数
+    pub fn decode_input(&self, data: &[u8]) -> Result<Vec<Token>> {
+        let d = &data[4..];
+        decode(&self.input_param_types(), &d)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use {Token, Param, Function, ParamType};
+
+    #[test]
+    fn test_function_encode_call() {
+        let interface = Function {
+            name: "baz".to_owned(),
+            inputs: vec![Param {
+                name: "a".to_owned(),
+                kind: ParamType::Uint(32),
+            }, Param {
+                name: "b".to_owned(),
+                kind: ParamType::Bool,
+            }],
+            outputs: vec![],
+            constant: false,
+        };
+
+        let func = Function::from(interface);
+        let mut uint = [0u8; 32];
+        uint[31] = 69;
+        let encoded = func.encode_input(&[Token::Uint(uint.into()), Token::Bool(true)]).unwrap();
+        let expected = hex!("cdcd77c000000000000000000000000000000000000000000000000000000000000000450000000000000000000000000000000000000000000000000000000000000001").to_vec();
+        assert_eq!(encoded, expected);
+    }
+}

libs/ethabi/src/lib.rs

+//! Ethereum ABI encoding decoding library.
+
+#![warn(missing_docs)]
+
+pub extern crate rustc_hex as hex;
+extern crate serde;
+extern crate serde_json;
+extern crate tiny_keccak;
+
+#[macro_use]
+pub extern crate serde_derive;
+
+#[macro_use]
+pub extern crate error_chain;
+
+#[cfg(test)]
+#[macro_use]
+extern crate hex_literal;
+
+#[cfg(test)]
+extern crate paste;
+
+extern crate ethereum_types;
+
+// add by echo >>>>>>>>
+//pub use error_chain;
+//pub use hex;
+
+// add by echo <<<<<<<<
+
+pub mod param_type;
+pub mod token;
+mod constructor;
+mod contract;
+mod decoder;
+mod encoder;
+mod errors;
+mod event;
+mod event_param;
+mod filter;
+mod function;
+mod log;
+mod operation;
+mod param;
+pub mod signature;
+mod util;
+
+#[cfg(test)]
+mod tests;
+
+pub use param_type::ParamType;
+pub use constructor::Constructor;
+pub use contract::{Contract, Functions, Events};
+pub use token::Token;
+pub use errors::{Error, ErrorKind, Result, ResultExt};
+pub use encoder::encode;
+pub use decoder::decode;
+pub use filter::{Topic, TopicFilter, RawTopicFilter};
+pub use function::Function;
+pub use param::Param;
+pub use log::{Log, RawLog, LogParam, ParseLog, LogFilter};
+pub use event::Event;
+pub use event_param::EventParam;
+
+/// ABI word.
+pub type Word = [u8; 32];
+
+/// ABI address.
+pub type Address = ethereum_types::Address;
+
+/// ABI fixed bytes.
+pub type FixedBytes = Vec<u8>;
+
+/// ABI bytes.
+pub type Bytes = Vec<u8>;
+
+/// ABI signed integer.
+pub type Int = ethereum_types::U256;
+
+/// ABI unsigned integer.
+pub type Uint = ethereum_types::U256;
+
+/// Commonly used FixedBytes of size 32
+pub type Hash = ethereum_types::H256;
+
+/// Contract functions generated by ethabi-derive
+pub trait FunctionOutputDecoder {
+	/// Output types of the contract function
+	type Output;
+
+	/// Decodes the given bytes output for the contract function
+	fn decode(&self, &[u8]) -> Result<Self::Output>;
+}

libs/ethabi/src/log.rs

+use {Hash, Token, Bytes, Result, TopicFilter};
+
+/// Common filtering functions that are available for any event.
+pub trait LogFilter {
+	/// Match any log parameters.
+	fn wildcard_filter(&self) -> TopicFilter;
+}
+
+/// trait common to things (events) that have an associated `Log` type
+/// that can be parsed from a `RawLog`
+pub trait ParseLog {
+	/// the associated `Log` type that can be parsed from a `RawLog`
+	/// by calling `parse_log`
+	type Log;
+
+	/// parse the associated `Log` type from a `RawLog`
+	fn parse_log(&self, log: RawLog) -> Result<Self::Log>;
+}
+
+/// Ethereum log.
+#[derive(Debug, PartialEq, Clone)]
+pub struct RawLog {
+	/// Indexed event params are represented as log topics.
+	pub topics: Vec<Hash>,
+	/// Others are just plain data.
+	pub data: Bytes,
+}
+
+impl From<(Vec<Hash>, Bytes)> for RawLog {
+	fn from(raw: (Vec<Hash>, Bytes)) -> Self {
+		RawLog {
+			topics: raw.0,
+			data: raw.1,
+		}
+	}
+}
+
+/// Decoded log param.
+#[derive(Debug, PartialEq, Clone)]
+pub struct LogParam {
+	/// Decoded log name.
+	pub name: String,
+	/// Decoded log value.
+	pub value: Token,
+}
+
+/// Decoded log.
+#[derive(Debug, PartialEq, Clone)]
+pub struct Log {
+	/// Log params.
+	pub params: Vec<LogParam>,
+}

libs/ethabi/src/operation.rs

+//! Operation type.
+
+use serde::{Deserialize, Deserializer};
+use serde::de::{Error as SerdeError};
+use serde_json::Value;
+use serde_json::value::from_value;
+use {Function, Constructor, Event};
+
+/// Operation type.
+#[derive(Clone, Debug, PartialEq)]
+pub enum Operation {
+	/// Contract constructor.
+	Constructor(Constructor),
+	/// Contract function.
+	Function(Function),
+	/// Contract event.
+	Event(Event),
+	/// Fallback, ignored.
+	Fallback,
+}
+
+impl<'a> Deserialize<'a> for Operation {
+	fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> where D: Deserializer<'a> {
+		let v: Value = try!(Deserialize::deserialize(deserializer));
+		let cloned = v.clone();
+		let map = try!(cloned.as_object().ok_or_else(|| SerdeError::custom("Invalid operation")));
+		let s = try!(map.get("type").and_then(Value::as_str).ok_or_else(|| SerdeError::custom("Invalid operation type")));
+
+		// This is a workaround to support non-spec compliant function and event names,
+		// see: https://github.com/paritytech/parity/issues/4122
+		fn sanitize_name(name: &mut String) {
+			if let Some(i) = name.find('(') {
+				name.truncate(i);
+			}
+		}
+
+		let result = match s {
+			"constructor" => from_value(v).map(Operation::Constructor),
+			"function" => from_value(v).map(|mut f: Function| {
+				sanitize_name(&mut f.name);
+				Operation::Function(f)
+			}),
+			"event" => from_value(v).map(|mut e: Event| {
+				sanitize_name(&mut e.name);
+				Operation::Event(e)
+			}),
+			"fallback" => Ok(Operation::Fallback),
+			_ => Err(SerdeError::custom("Invalid operation type.")),
+		};
+		result.map_err(|e| D::Error::custom(e.to_string()))
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use serde_json;
+	use super::Operation;
+	use {Function, Param, ParamType};
+
+	#[test]
+	fn deserialize_operation() {
+		let s = r#"{
+			"type":"function",
+			"inputs": [{
+				"name":"a",
+				"type":"address"
+			}],
+			"name":"foo",
+			"outputs": []
+		}"#;
+
+		let deserialized: Operation = serde_json::from_str(s).unwrap();
+
+		assert_eq!(deserialized, Operation::Function(Function {
+			name: "foo".to_owned(),
+			inputs: vec![
+				Param {
+					name: "a".to_owned(),
+					kind: ParamType::Address,
+				}
+			],
+			outputs: vec![],
+			constant: false,
+		}));
+	}
+
+	#[test]
+	fn deserialize_sanitize_function_name() {
+		fn test_sanitize_function_name(name: &str, expected: &str) {
+			let s = format!(r#"{{
+				"type":"function",
+				"inputs": [{{
+					"name":"a",
+					"type":"address"
+				}}],
+				"name":"{}",
+				"outputs": []
+			}}"#, name);
+
+			let deserialized: Operation = serde_json::from_str(&s).unwrap();
+			let function = match deserialized {
+				Operation::Function(f) => f,
+				_ => panic!("expected funciton"),
+			};
+
+			assert_eq!(function.name, expected);
+		}
+
+		test_sanitize_function_name("foo", "foo");
+		test_sanitize_function_name("foo()", "foo");
+		test_sanitize_function_name("()", "");
+		test_sanitize_function_name("", "");
+	}
+
+	#[test]
+	fn deserialize_sanitize_event_name() {
+		fn test_sanitize_event_name(name: &str, expected: &str) {
+			let s = format!(r#"{{
+				"type":"event",
+					"inputs": [{{
+						"name":"a",
+						"type":"address",
+						"indexed":true
+					}}],
+					"name":"{}",
+					"outputs": [],
+					"anonymous": false
+			}}"#, name);
+
+			let deserialized: Operation = serde_json::from_str(&s).unwrap();
+			let event = match deserialized {
+				Operation::Event(e) => e,
+				_ => panic!("expected event!"),
+			};
+
+			assert_eq!(event.name, expected);
+		}
+
+		test_sanitize_event_name("foo", "foo");
+		test_sanitize_event_name("foo()", "foo");
+		test_sanitize_event_name("()", "");
+		test_sanitize_event_name("", "");
+	}
+}

libs/ethabi/src/param.rs

+//! Function param.
+use ParamType;
+
+/// Function param.
+#[derive(Debug, Clone, PartialEq, Deserialize)]
+pub struct Param {
+	/// Param name.
+	pub name: String,
+	/// Param type.
+	#[serde(rename="type")]
+	pub kind: ParamType,
+}
+
+#[cfg(test)]
+mod tests {
+	use serde_json;
+	use {Param, ParamType};
+
+	#[test]
+	fn param_deserialization() {
+		let s = r#"{
+			"name": "foo",
+			"type": "address"
+		}"#;
+
+		let deserialized: Param = serde_json::from_str(s).unwrap();
+
+		assert_eq!(deserialized, Param {
+			name: "foo".to_owned(),
+			kind: ParamType::Address,
+		});
+	}
+}

libs/ethabi/src/param_type/deserialize.rs

+use std::fmt;
+use serde::{Deserialize, Deserializer};
+use serde::de::{Error as SerdeError, Visitor};
+use super::{ParamType, Reader};
+
+impl<'a> Deserialize<'a> for ParamType {
+	fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> where D: Deserializer<'a> {
+		deserializer.deserialize_identifier(ParamTypeVisitor)
+	}
+}
+
+struct ParamTypeVisitor;
+
+impl<'a> Visitor<'a> for ParamTypeVisitor {
+	type Value = ParamType;
+
+	fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+		write!(formatter, "a correct name of abi-encodable parameter type")
+	}
+
+	fn visit_str<E>(self, value: &str) -> Result<Self::Value, E> where E: SerdeError {
+		Reader::read(value).map_err(|e| SerdeError::custom(format!("{:?}", e).as_str()))
+	}
+
+	fn visit_string<E>(self, value: String) -> Result<Self::Value, E> where E: SerdeError {
+		self.visit_str(value.as_str())
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use serde_json;
+	use ParamType;
+
+	#[test]
+	fn param_type_deserialization() {
+		let s = r#"["address", "bytes", "bytes32", "bool", "string", "int", "uint", "address[]", "uint[3]", "bool[][5]"]"#;
+		let deserialized: Vec<ParamType> = serde_json::from_str(s).unwrap();
+		assert_eq!(deserialized, vec![
+			ParamType::Address,
+			ParamType::Bytes,
+			ParamType::FixedBytes(32),
+			ParamType::Bool,
+			ParamType::String,
+			ParamType::Int(256),
+			ParamType::Uint(256),
+			ParamType::Array(Box::new(ParamType::Address)),
+			ParamType::FixedArray(Box::new(ParamType::Uint(256)), 3),
+			ParamType::FixedArray(Box::new(ParamType::Array(Box::new(ParamType::Bool))), 5)
+		]);
+	}
+}

libs/ethabi/src/param_type/mod.rs

+//! Function and event param types.
+
+mod deserialize;
+mod param_type;
+mod reader;
+mod writer;
+
+pub use self::param_type::ParamType;
+pub use self::writer::Writer;
+pub use self::reader::Reader;

libs/ethabi/src/param_type/param_type.rs

+//! Function and event param types.
+
+use std::fmt;
+use super::Writer;
+
+/// Function and event param types.
+#[derive(Debug, Clone, PartialEq)]
+pub enum ParamType {
+	/// Address.
+	Address,
+	/// Bytes.
+	Bytes,
+	/// Signed integer.
+	Int(usize),
+	/// Unsigned integer.
+	Uint(usize),
+	/// Boolean.
+	Bool,
+	/// String.
+	String,
+	/// Array of unknown size.
+	Array(Box<ParamType>),
+	/// Vector of bytes with fixed size.
+	FixedBytes(usize),
+	/// Array with fixed size.
+	FixedArray(Box<ParamType>, usize),
+}
+
+impl fmt::Display for ParamType {
+	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+		write!(f, "{}", Writer::write(self))
+	}
+}
+
+impl ParamType {
+    /// returns whether a zero length byte slice (`0x`) is
+    /// a valid encoded form of this param type
+    pub fn is_empty_bytes_valid_encoding(&self) -> bool {
+        match self {
+            ParamType::FixedBytes(len) => *len == 0,
+            ParamType::FixedArray(_, len) => *len == 0,
+            _ => false,
+        }
+    }
+
+	/// returns whether this param type is dynamic
+	pub fn is_dynamic(&self) -> bool {
+		match self {
+			ParamType::Bytes | ParamType::String | ParamType::Array(_) => true,
+			ParamType::FixedArray(elem_type, _) => elem_type.is_dynamic(),
+			_ => false
+		}
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use ParamType;
+
+	#[test]
+	fn test_param_type_display() {
+		assert_eq!(format!("{}", ParamType::Address), "address".to_owned());
+		assert_eq!(format!("{}", ParamType::Bytes), "bytes".to_owned());
+		assert_eq!(format!("{}", ParamType::FixedBytes(32)), "bytes32".to_owned());
+		assert_eq!(format!("{}", ParamType::Uint(256)), "uint256".to_owned());
+		assert_eq!(format!("{}", ParamType::Int(64)), "int64".to_owned());
+		assert_eq!(format!("{}", ParamType::Bool), "bool".to_owned());
+		assert_eq!(format!("{}", ParamType::String), "string".to_owned());
+		assert_eq!(format!("{}", ParamType::Array(Box::new(ParamType::Bool))), "bool[]".to_owned());
+		assert_eq!(format!("{}", ParamType::FixedArray(Box::new(ParamType::Uint(256)), 2)), "uint256[2]".to_owned());
+		assert_eq!(format!("{}", ParamType::FixedArray(Box::new(ParamType::String), 2)), "string[2]".to_owned());
+		assert_eq!(format!("{}", ParamType::FixedArray(Box::new(ParamType::Array(Box::new(ParamType::Bool))), 2)), "bool[][2]".to_owned());
+	}
+
+	#[test]
+	fn test_is_dynamic() {
+		assert_eq!(ParamType::Address.is_dynamic(), false);
+		assert_eq!(ParamType::Bytes.is_dynamic(), true);
+		assert_eq!(ParamType::FixedBytes(32).is_dynamic(), false);
+		assert_eq!(ParamType::Uint(256).is_dynamic(), false);
+		assert_eq!(ParamType::Int(64).is_dynamic(), false);
+		assert_eq!(ParamType::Bool.is_dynamic(), false);
+		assert_eq!(ParamType::String.is_dynamic(), true);
+		assert_eq!(ParamType::Array(Box::new(ParamType::Bool)).is_dynamic(), true);
+		assert_eq!(ParamType::FixedArray(Box::new(ParamType::Uint(256)), 2).is_dynamic(), false);
+		assert_eq!(ParamType::FixedArray(Box::new(ParamType::String), 2).is_dynamic(), true);
+		assert_eq!(ParamType::FixedArray(Box::new(ParamType::Array(Box::new(ParamType::Bool))), 2).is_dynamic(), true);
+	}
+}

libs/ethabi/src/param_type/reader.rs

+use {ParamType, Error, ErrorKind};
+
+/// Used to convert param type represented as a string to rust structure.
+pub struct Reader;
+
+impl Reader {
+	/// Converts string to param type.
+	pub fn read(name: &str) -> Result<ParamType, Error> {
+		// check if it is a fixed or dynamic array.
+		if let Some(']') = name.chars().last() {
+			// take number part
+			let num: String = name.chars()
+				.rev()
+				.skip(1)
+				.take_while(|c| *c != '[')
+				.collect::<String>()
+				.chars()
+				.rev()
+				.collect();
+
+			let count = name.chars().count();
+			if num.is_empty() {
+				// we already know it's a dynamic array!
+				let subtype = try!(Reader::read(&name[..count - 2]));
+				return Ok(ParamType::Array(Box::new(subtype)));
+			} else {
+				// it's a fixed array.
+				let len = try!(usize::from_str_radix(&num, 10));
+				let subtype = try!(Reader::read(&name[..count - num.len() - 2]));
+				return Ok(ParamType::FixedArray(Box::new(subtype), len));
+			}
+		}
+
+		let result = match name {
+			"address" => ParamType::Address,
+			"bytes" => ParamType::Bytes,
+			"bool" => ParamType::Bool,
+			"string" => ParamType::String,
+			"int" => ParamType::Int(256),
+			"uint" => ParamType::Uint(256),
+			s if s.starts_with("int") => {
+				let len = try!(usize::from_str_radix(&s[3..], 10));
+				ParamType::Int(len)
+			},
+			s if s.starts_with("uint") => {
+				let len = try!(usize::from_str_radix(&s[4..], 10));
+				ParamType::Uint(len)
+			},
+			s if s.starts_with("bytes") => {
+				let len = try!(usize::from_str_radix(&s[5..], 10));
+				ParamType::FixedBytes(len)
+			},
+			_ => {
+				return Err(ErrorKind::InvalidName(name.to_owned()).into());
+			}
+		};
+
+		Ok(result)
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use ParamType;
+	use super::Reader;
+
+	#[test]
+	fn test_read_param() {
+		assert_eq!(Reader::read("address").unwrap(), ParamType::Address);
+		assert_eq!(Reader::read("bytes").unwrap(), ParamType::Bytes);
+		assert_eq!(Reader::read("bytes32").unwrap(), ParamType::FixedBytes(32));
+		assert_eq!(Reader::read("bool").unwrap(), ParamType::Bool);
+		assert_eq!(Reader::read("string").unwrap(), ParamType::String);
+		assert_eq!(Reader::read("int").unwrap(), ParamType::Int(256));
+		assert_eq!(Reader::read("uint").unwrap(), ParamType::Uint(256));
+		assert_eq!(Reader::read("int32").unwrap(), ParamType::Int(32));
+		assert_eq!(Reader::read("uint32").unwrap(), ParamType::Uint(32));
+	}
+
+	#[test]
+	fn test_read_array_param() {
+		assert_eq!(Reader::read("address[]").unwrap(), ParamType::Array(Box::new(ParamType::Address)));
+		assert_eq!(Reader::read("uint[]").unwrap(), ParamType::Array(Box::new(ParamType::Uint(256))));
+		assert_eq!(Reader::read("bytes[]").unwrap(), ParamType::Array(Box::new(ParamType::Bytes)));
+		assert_eq!(Reader::read("bool[][]").unwrap(), ParamType::Array(Box::new(ParamType::Array(Box::new(ParamType::Bool)))));
+	}
+
+	#[test]
+	fn test_read_fixed_array_param() {
+		assert_eq!(Reader::read("address[2]").unwrap(), ParamType::FixedArray(Box::new(ParamType::Address), 2));
+		assert_eq!(Reader::read("bool[17]").unwrap(), ParamType::FixedArray(Box::new(ParamType::Bool), 17));
+		assert_eq!(Reader::read("bytes[45][3]").unwrap(), ParamType::FixedArray(Box::new(ParamType::FixedArray(Box::new(ParamType::Bytes), 45)), 3));
+	}
+
+	#[test]
+	fn test_read_mixed_arrays() {
+		assert_eq!(Reader::read("bool[][3]").unwrap(), ParamType::FixedArray(Box::new(ParamType::Array(Box::new(ParamType::Bool))), 3));
+		assert_eq!(Reader::read("bool[3][]").unwrap(), ParamType::Array(Box::new(ParamType::FixedArray(Box::new(ParamType::Bool), 3))));
+	}
+}

libs/ethabi/src/param_type/writer.rs

+use ParamType;
+
+/// Output formatter for param type.
+pub struct Writer;
+
+impl Writer {
+	/// Returns string which is a formatted represenation of param.
+	pub fn write(param: &ParamType) -> String {
+		match *param {
+			ParamType::Address => "address".to_owned(),
+			ParamType::Bytes => "bytes".to_owned(),
+			ParamType::FixedBytes(len) => format!("bytes{}", len),
+			ParamType::Int(len) => format!("int{}", len),
+			ParamType::Uint(len) => format!("uint{}", len),
+			ParamType::Bool => "bool".to_owned(),
+			ParamType::String => "string".to_owned(),
+			ParamType::FixedArray(ref param, len) => format!("{}[{}]", Writer::write(param), len),
+			ParamType::Array(ref param) => format!("{}[]", Writer::write(param)),
+		}
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use ParamType;
+	use super::Writer;
+
+	#[test]
+	fn test_write_param() {
+		assert_eq!(Writer::write(&ParamType::Address), "address".to_owned());
+		assert_eq!(Writer::write(&ParamType::Bytes), "bytes".to_owned());
+		assert_eq!(Writer::write(&ParamType::FixedBytes(32)), "bytes32".to_owned());
+		assert_eq!(Writer::write(&ParamType::Uint(256)), "uint256".to_owned());
+		assert_eq!(Writer::write(&ParamType::Int(64)), "int64".to_owned());
+		assert_eq!(Writer::write(&ParamType::Bool), "bool".to_owned());
+		assert_eq!(Writer::write(&ParamType::String), "string".to_owned());
+		assert_eq!(Writer::write(&ParamType::Array(Box::new(ParamType::Bool))), "bool[]".to_owned());
+		assert_eq!(Writer::write(&ParamType::FixedArray(Box::new(ParamType::String), 2)), "string[2]".to_owned());
+		assert_eq!(Writer::write(&ParamType::FixedArray(Box::new(ParamType::Array(Box::new(ParamType::Bool))), 2)), "bool[][2]".to_owned());
+	}
+}

libs/ethabi/src/signature.rs

+use tiny_keccak::Keccak;
+use param_type::{Writer, ParamType};
+use Hash;
+
+pub fn short_signature(name: &str, params: &[ParamType]) -> [u8; 4] {
+	let mut result = [0u8; 4];
+	fill_signature(name, params, &mut result);
+	result
+}
+
+pub fn long_signature(name: &str, params: &[ParamType]) -> Hash {
+	let mut result = [0u8; 32];
+	fill_signature(name, params, &mut result);
+	result.into()
+}
+
+fn fill_signature(name: &str, params: &[ParamType], result: &mut [u8]) {
+	let types = params.iter()
+		.map(Writer::write)
+		.collect::<Vec<String>>()
+		.join(",");
+
+	let data: Vec<u8> = From::from(format!("{}({})", name, types).as_str());
+
+	let mut sponge = Keccak::new_keccak256();
+	sponge.update(&data);
+	sponge.finalize(result);
+}
+
+#[cfg(test)]
+mod tests {
+	use super::short_signature;
+	use {ParamType};
+
+	#[test]
+	fn test_signature() {
+		assert_eq!(hex!("cdcd77c0"), short_signature("baz", &[ParamType::Uint(32), ParamType::Bool]));
+	}
+}

libs/ethabi/src/tests.rs

+use {encode, decode, Token, ParamType};
+
+macro_rules! test_encode_decode {
+	(name: $name:tt, types: $types:expr, tokens: $tokens:expr, data: $data:tt) => {
+		$crate::paste::item! {
+			#[test]
+			fn [<encode_ $name>]() {
+				let encoded = encode(&$tokens);
+				let expected = $crate::hex_literal::hex!($data).to_vec();
+				assert_eq!(encoded, expected);
+			}
+
+			#[test]
+			fn [<decode_ $name>]() {
+				let encoded = hex!($data);
+				let expected = $tokens;
+				let decoded = decode(&$types, &encoded).unwrap();
+				assert_eq!(decoded, expected);
+			}
+		}
+	}
+}
+
+// test address
+test_encode_decode! {
+	name: address,
+	types: [ParamType::Address],
+	tokens: [Token::Address([0x11u8; 20].into())],
+	data: "0000000000000000000000001111111111111111111111111111111111111111"
+}
+test_encode_decode! {
+	name: addresses,
+	types: [
+	  ParamType::Address,
+	  ParamType::Address
+	],
+	tokens: [
+	  Token::Address([0x11u8; 20].into()),
+	  Token::Address([0x22u8; 20].into())
+	],
+	data: "
+		0000000000000000000000001111111111111111111111111111111111111111
+		0000000000000000000000002222222222222222222222222222222222222222"
+}
+
+// test bytes
+test_encode_decode! {
+	name: bytes,
+	types: [ParamType::Bytes],
+	tokens: [Token::Bytes(vec![0x12, 0x34])],
+	data: "
+		0000000000000000000000000000000000000000000000000000000000000020
+		0000000000000000000000000000000000000000000000000000000000000002
+		1234000000000000000000000000000000000000000000000000000000000000"
+}
+test_encode_decode! {
+	name: bytes2,
+	types: [ParamType::Bytes],
+	tokens: [Token::Bytes(hex!("10000000000000000000000000000000000000000000000000000000000002").to_vec())],
+	data: "
+		0000000000000000000000000000000000000000000000000000000000000020
+		000000000000000000000000000000000000000000000000000000000000001f
+		1000000000000000000000000000000000000000000000000000000000000200"
+}
+test_encode_decode! {
+	name: bytes3,
+	types: [ParamType::Bytes],
+	tokens: [
+		Token::Bytes(hex!("
+			1000000000000000000000000000000000000000000000000000000000000000
+			1000000000000000000000000000000000000000000000000000000000000000
+		").to_vec())
+	],
+	data: "
+		0000000000000000000000000000000000000000000000000000000000000020
+		0000000000000000000000000000000000000000000000000000000000000040
+		1000000000000000000000000000000000000000000000000000000000000000
+		1000000000000000000000000000000000000000000000000000000000000000"
+}
+test_encode_decode! {
+	name: two_bytes,
+	types: [ParamType::Bytes, ParamType::Bytes],
+	tokens: [
+		Token::Bytes(hex!("10000000000000000000000000000000000000000000000000000000000002").to_vec()),
+		Token::Bytes(hex!("0010000000000000000000000000000000000000000000000000000000000002").to_vec())
+	],
+	data: "
+		0000000000000000000000000000000000000000000000000000000000000040
+		0000000000000000000000000000000000000000000000000000000000000080
+		000000000000000000000000000000000000000000000000000000000000001f
+		1000000000000000000000000000000000000000000000000000000000000200
+		0000000000000000000000000000000000000000000000000000000000000020
+		0010000000000000000000000000000000000000000000000000000000000002"
+}
+
+// test int
+test_encode_decode! {
+	name: int,
+	types: [ParamType::Int(32)],
+	tokens: [Token::Int([0x11u8; 32].into())],
+	data: "1111111111111111111111111111111111111111111111111111111111111111"
+}
+test_encode_decode! {
+	name: int2,
+	types: [ParamType::Int(32)],
+	tokens: {
+		let mut int = [0u8; 32];
+		int[31] = 4;
+		[Token::Int(int.into())]
+	},
+	data: "0000000000000000000000000000000000000000000000000000000000000004"
+}
+
+// test uint
+test_encode_decode! {
+	name: uint,
+	types: [ParamType::Uint(32)],
+	tokens: [Token::Uint([0x11u8; 32].into())],
+	data: "1111111111111111111111111111111111111111111111111111111111111111"
+}
+test_encode_decode! {
+	name: uint2,
+	types: [ParamType::Uint(32)],
+	tokens: {
+		let mut uint = [0u8; 32];
+		uint[31] = 4;
+		[Token::Uint(uint.into())]
+	},
+	data: "0000000000000000000000000000000000000000000000000000000000000004"
+}
+
+// test bool
+test_encode_decode! {
+	name: bool,
+	types: [ParamType::Bool],
+	tokens: [Token::Bool(true)],
+	data: "0000000000000000000000000000000000000000000000000000000000000001"
+}
+test_encode_decode! {
+	name: bool2,
+	types: [ParamType::Bool],
+	tokens: [Token::Bool(false)],
+	data: "0000000000000000000000000000000000000000000000000000000000000000"
+}
+
+// test string
+test_encode_decode! {
+	name: string,
+	types: [ParamType::String],
+	tokens: [Token::String("gavofyork".to_owned())],
+	data: "
+		0000000000000000000000000000000000000000000000000000000000000020
+		0000000000000000000000000000000000000000000000000000000000000009
+		6761766f66796f726b0000000000000000000000000000000000000000000000"
+}
+
+// test array
+test_encode_decode! {
+	name: dynamic_array_of_addresses,
+	types: [ParamType::Array(Box::new(ParamType::Address))],
+	tokens: {
+		let address1 = Token::Address([0x11u8; 20].into());
+		let address2 = Token::Address([0x22u8; 20].into());
+		[Token::Array(vec![address1, address2])]
+	},
+	data: "
+		0000000000000000000000000000000000000000000000000000000000000020
+		0000000000000000000000000000000000000000000000000000000000000002
+		0000000000000000000000001111111111111111111111111111111111111111
+		0000000000000000000000002222222222222222222222222222222222222222"
+}
+test_encode_decode! {
+	name: dynamic_array_of_fixed_arrays_of_addresses,
+	types: [
+		ParamType::Array(Box::new(
+			ParamType::FixedArray(Box::new(ParamType::Address), 2)
+		))
+	],
+	tokens: {
+		let address1 = Token::Address([0x11u8; 20].into());
+		let address2 = Token::Address([0x22u8; 20].into());
+		let address3 = Token::Address([0x33u8; 20].into());
+		let address4 = Token::Address([0x44u8; 20].into());
+		let array0 = Token::FixedArray(vec![address1, address2]);
+		let array1 = Token::FixedArray(vec![address3, address4]);
+		[Token::Array(vec![array0, array1])]
+	},
+   	data: "
+		0000000000000000000000000000000000000000000000000000000000000020
+		0000000000000000000000000000000000000000000000000000000000000002
+		0000000000000000000000001111111111111111111111111111111111111111
+		0000000000000000000000002222222222222222222222222222222222222222
+		0000000000000000000000003333333333333333333333333333333333333333
+		0000000000000000000000004444444444444444444444444444444444444444"
+}
+test_encode_decode! {
+	name: dynamic_array_of_fixed_arrays_of_dynamic_array,
+	types: [
+		ParamType::Array(Box::new(
+			ParamType::FixedArray(Box::new(ParamType::Array(Box::new(ParamType::Address))), 2)
+		))
+	],
+	tokens: {
+		let address1 = Token::Address([0x11u8; 20].into());
+		let address2 = Token::Address([0x22u8; 20].into());
+		let address3 = Token::Address([0x33u8; 20].into());
+		let address4 = Token::Address([0x44u8; 20].into());
+		let address5 = Token::Address([0x55u8; 20].into());
+		let address6 = Token::Address([0x66u8; 20].into());
+		let address7 = Token::Address([0x77u8; 20].into());
+		let address8 = Token::Address([0x88u8; 20].into());
+		let array0 = Token::FixedArray(vec![
+			Token::Array(vec![address1, address2]),
+			Token::Array(vec![address3, address4]),
+		]);
+		let array1 = Token::FixedArray(vec![
+			Token::Array(vec![address5, address6]),
+			Token::Array(vec![address7, address8]),
+		]);
+		[Token::Array(vec![array0, array1])]
+	},
+	data: "
+		0000000000000000000000000000000000000000000000000000000000000020
+		0000000000000000000000000000000000000000000000000000000000000002
+		0000000000000000000000000000000000000000000000000000000000000040
+		0000000000000000000000000000000000000000000000000000000000000140
+		0000000000000000000000000000000000000000000000000000000000000040
+		00000000000000000000000000000000000000000000000000000000000000a0
+		0000000000000000000000000000000000000000000000000000000000000002
+		0000000000000000000000001111111111111111111111111111111111111111
+		0000000000000000000000002222222222222222222222222222222222222222
+		0000000000000000000000000000000000000000000000000000000000000002
+		0000000000000000000000003333333333333333333333333333333333333333
+		0000000000000000000000004444444444444444444444444444444444444444
+		0000000000000000000000000000000000000000000000000000000000000040
+		00000000000000000000000000000000000000000000000000000000000000a0
+		0000000000000000000000000000000000000000000000000000000000000002
+		0000000000000000000000005555555555555555555555555555555555555555
+		0000000000000000000000006666666666666666666666666666666666666666
+		0000000000000000000000000000000000000000000000000000000000000002
+		0000000000000000000000007777777777777777777777777777777777777777
+		0000000000000000000000008888888888888888888888888888888888888888"
+}
+test_encode_decode! {
+	name: dynamic_array_of_dynamic_arrays,
+	types: [
+		ParamType::Array(Box::new(
+			ParamType::Array(Box::new(ParamType::Address))
+		))
+	],
+	tokens: {
+		let address1 = Token::Address([0x11u8; 20].into());
+		let address2 = Token::Address([0x22u8; 20].into());
+		let array0 = Token::Array(vec![address1]);
+		let array1 = Token::Array(vec![address2]);
+		let dynamic = Token::Array(vec![array0, array1]);
+		[dynamic]
+	},
+	data: "
+		0000000000000000000000000000000000000000000000000000000000000020
+		0000000000000000000000000000000000000000000000000000000000000002
+		0000000000000000000000000000000000000000000000000000000000000040
+		0000000000000000000000000000000000000000000000000000000000000080
+		0000000000000000000000000000000000000000000000000000000000000001
+		0000000000000000000000001111111111111111111111111111111111111111
+		0000000000000000000000000000000000000000000000000000000000000001
+		0000000000000000000000002222222222222222222222222222222222222222"
+}
+test_encode_decode! {
+	name: dynamic_array_of_dynamic_arrays2,
+	types: [
+		ParamType::Array(Box::new(
+			ParamType::Array(Box::new(ParamType::Address))
+		))
+	],
+	tokens: {
+		let address1 = Token::Address([0x11u8; 20].into());
+		let address2 = Token::Address([0x22u8; 20].into());
+		let address3 = Token::Address([0x33u8; 20].into());
+		let address4 = Token::Address([0x44u8; 20].into());
+		let array0 = Token::Array(vec![address1, address2]);
+		let array1 = Token::Array(vec![address3, address4]);
+		let dynamic = Token::Array(vec![array0, array1]);
+		[dynamic]
+	},
+	data: "
+		0000000000000000000000000000000000000000000000000000000000000020
+		0000000000000000000000000000000000000000000000000000000000000002
+		0000000000000000000000000000000000000000000000000000000000000040
+		00000000000000000000000000000000000000000000000000000000000000a0
+		0000000000000000000000000000000000000000000000000000000000000002
+		0000000000000000000000001111111111111111111111111111111111111111
+		0000000000000000000000002222222222222222222222222222222222222222
+		0000000000000000000000000000000000000000000000000000000000000002
+		0000000000000000000000003333333333333333333333333333333333333333
+		0000000000000000000000004444444444444444444444444444444444444444"
+}
+test_encode_decode! {
+	name: dynamic_array_of_bytes,
+	types: [ParamType::Array(Box::new(ParamType::Bytes))],
+	tokens: {
+		let bytes = hex!("019c80031b20d5e69c8093a571162299032018d913930d93ab320ae5ea44a4218a274f00d607").to_vec();
+		[Token::Array(vec![Token::Bytes(bytes)])]
+	},
+	data: "
+		0000000000000000000000000000000000000000000000000000000000000020
+		0000000000000000000000000000000000000000000000000000000000000001
+		0000000000000000000000000000000000000000000000000000000000000020
+		0000000000000000000000000000000000000000000000000000000000000026
+		019c80031b20d5e69c8093a571162299032018d913930d93ab320ae5ea44a421
+		8a274f00d6070000000000000000000000000000000000000000000000000000"
+}
+test_encode_decode! {
+	name: dynamic_array_of_bytes2,
+	types: [ParamType::Array(Box::new(ParamType::Bytes))],
+	tokens: [
+		Token::Array(vec![
+			Token::Bytes(hex!("4444444444444444444444444444444444444444444444444444444444444444444444444444").to_vec()),
+			Token::Bytes(hex!("6666666666666666666666666666666666666666666666666666666666666666666666666666").to_vec()),
+		])
+	],
+	data: "
+		0000000000000000000000000000000000000000000000000000000000000020
+		0000000000000000000000000000000000000000000000000000000000000002
+		0000000000000000000000000000000000000000000000000000000000000040
+		00000000000000000000000000000000000000000000000000000000000000a0
+		0000000000000000000000000000000000000000000000000000000000000026
+		4444444444444444444444444444444444444444444444444444444444444444
+		4444444444440000000000000000000000000000000000000000000000000000
+		0000000000000000000000000000000000000000000000000000000000000026
+		6666666666666666666666666666666666666666666666666666666666666666
+		6666666666660000000000000000000000000000000000000000000000000000"
+}
+test_encode_decode! {
+	name: empty_dynamic_array,
+	types: [
+		ParamType::Array(Box::new(ParamType::Bool)),
+		ParamType::Array(Box::new(ParamType::Bool)),
+	],
+	tokens: [
+		Token::Array(vec![]),
+		Token::Array(vec![])
+	],
+	data: "
+		0000000000000000000000000000000000000000000000000000000000000040
+		0000000000000000000000000000000000000000000000000000000000000060
+		0000000000000000000000000000000000000000000000000000000000000000
+		0000000000000000000000000000000000000000000000000000000000000000"
+}
+test_encode_decode! {
+	name: dynamic_array_of_empty_dynamic_array,
+	types: [
+		ParamType::Array(Box::new(ParamType::Array(Box::new(ParamType::Bool)))),
+		ParamType::Array(Box::new(ParamType::Array(Box::new(ParamType::Bool)))),
+	],
+	tokens: [
+		Token::Array(vec![Token::Array(vec![])]),
+		Token::Array(vec![Token::Array(vec![])]),
+	],
+	data: "
+		0000000000000000000000000000000000000000000000000000000000000040
+		00000000000000000000000000000000000000000000000000000000000000a0
+		0000000000000000000000000000000000000000000000000000000000000001
+		0000000000000000000000000000000000000000000000000000000000000020
+		0000000000000000000000000000000000000000000000000000000000000000
+		0000000000000000000000000000000000000000000000000000000000000001
+		0000000000000000000000000000000000000000000000000000000000000020
+		0000000000000000000000000000000000000000000000000000000000000000"
+}
+
+// test fixed array
+test_encode_decode! {
+	name: fixed_array_of_addresses,
+	types: [ParamType::FixedArray(Box::new(ParamType::Address), 2)],
+	tokens: {
+		let address1 = Token::Address([0x11u8; 20].into());
+		let address2 = Token::Address([0x22u8; 20].into());
+		[Token::FixedArray(vec![address1, address2])]
+	},
+	data: "
+		0000000000000000000000001111111111111111111111111111111111111111
+		0000000000000000000000002222222222222222222222222222222222222222"
+}
+test_encode_decode! {
+	name: fixed_array_of_fixed_arrays,
+	types: [
+		ParamType::FixedArray(
+			Box::new(ParamType::FixedArray(Box::new(ParamType::Address), 2)),
+			2
+		)
+	],
+	tokens: {
+		let address1 = Token::Address([0x11u8; 20].into());
+		let address2 = Token::Address([0x22u8; 20].into());
+		let address3 = Token::Address([0x33u8; 20].into());
+		let address4 = Token::Address([0x44u8; 20].into());
+		let array0 = Token::FixedArray(vec![address1, address2]);
+		let array1 = Token::FixedArray(vec![address3, address4]);
+		let fixed = Token::FixedArray(vec![array0, array1]);
+		[fixed]
+	},
+	data: "
+		0000000000000000000000001111111111111111111111111111111111111111
+		0000000000000000000000002222222222222222222222222222222222222222
+		0000000000000000000000003333333333333333333333333333333333333333
+		0000000000000000000000004444444444444444444444444444444444444444"
+}
+test_encode_decode! {
+	name: fixed_array_of_dynamic_array_of_addresses,
+	types: [
+		ParamType::FixedArray(
+			Box::new(ParamType::Array(Box::new(ParamType::Address))),
+			2
+		)
+	],
+	tokens: {
+		let address1 = Token::Address([0x11u8; 20].into());
+		let address2 = Token::Address([0x22u8; 20].into());
+		let address3 = Token::Address([0x33u8; 20].into());
+		let address4 = Token::Address([0x44u8; 20].into());
+		let array0 = Token::Array(vec![address1, address2]);
+		let array1 = Token::Array(vec![address3, address4]);
+		[Token::FixedArray(vec![array0, array1])]
+	},
+	data: "
+		0000000000000000000000000000000000000000000000000000000000000020
+		0000000000000000000000000000000000000000000000000000000000000040
+		00000000000000000000000000000000000000000000000000000000000000a0
+		0000000000000000000000000000000000000000000000000000000000000002
+		0000000000000000000000001111111111111111111111111111111111111111
+		0000000000000000000000002222222222222222222222222222222222222222
+		0000000000000000000000000000000000000000000000000000000000000002
+		0000000000000000000000003333333333333333333333333333333333333333
+		0000000000000000000000004444444444444444444444444444444444444444"
+}
+
+// test fixed bytes
+test_encode_decode! {
+	name: fixed_bytes,
+	types: [ParamType::FixedBytes(2)],
+	tokens: [Token::FixedBytes(vec![0x12, 0x34])],
+	data: "1234000000000000000000000000000000000000000000000000000000000000"
+}
+
+// comprehensive test
+test_encode_decode! {
+	name: comprehensive_test,
+	types: [
+		ParamType::Int(32),
+		ParamType::Bytes,
+		ParamType::Int(32),
+		ParamType::Bytes,
+	],
+	tokens: {
+		let bytes = hex!("
+			131a3afc00d1b1e3461b955e53fc866dcf303b3eb9f4c16f89e388930f48134b
+			131a3afc00d1b1e3461b955e53fc866dcf303b3eb9f4c16f89e388930f48134b
+		").to_vec();
+		[
+			Token::Int(5.into()),
+			Token::Bytes(bytes.clone()),
+			Token::Int(3.into()),
+			Token::Bytes(bytes),
+		]
+	},
+	data: "
+		0000000000000000000000000000000000000000000000000000000000000005
+		0000000000000000000000000000000000000000000000000000000000000080
+		0000000000000000000000000000000000000000000000000000000000000003
+		00000000000000000000000000000000000000000000000000000000000000e0
+		0000000000000000000000000000000000000000000000000000000000000040
+		131a3afc00d1b1e3461b955e53fc866dcf303b3eb9f4c16f89e388930f48134b
+		131a3afc00d1b1e3461b955e53fc866dcf303b3eb9f4c16f89e388930f48134b
+		0000000000000000000000000000000000000000000000000000000000000040
+		131a3afc00d1b1e3461b955e53fc866dcf303b3eb9f4c16f89e388930f48134b
+		131a3afc00d1b1e3461b955e53fc866dcf303b3eb9f4c16f89e388930f48134b"
+}
+test_encode_decode! {
+	name: comprehensive_test2,
+	types: [
+		ParamType::Int(32),
+		ParamType::String,
+		ParamType::Int(32),
+		ParamType::Int(32),
+		ParamType::Int(32),
+		ParamType::Array(Box::new(ParamType::Int(32))),
+	],
+	tokens: [
+		Token::Int(1.into()),
+		Token::String("gavofyork".to_owned()),
+		Token::Int(2.into()),
+		Token::Int(3.into()),
+		Token::Int(4.into()),
+		Token::Array(vec![
+			Token::Int(5.into()),
+			Token::Int(6.into()),
+			Token::Int(7.into()),
+		])
+	],
+	data: "
+		0000000000000000000000000000000000000000000000000000000000000001
+		00000000000000000000000000000000000000000000000000000000000000c0
+		0000000000000000000000000000000000000000000000000000000000000002
+		0000000000000000000000000000000000000000000000000000000000000003
+		0000000000000000000000000000000000000000000000000000000000000004
+		0000000000000000000000000000000000000000000000000000000000000100
+		0000000000000000000000000000000000000000000000000000000000000009
+		6761766f66796f726b0000000000000000000000000000000000000000000000
+		0000000000000000000000000000000000000000000000000000000000000003
+		0000000000000000000000000000000000000000000000000000000000000005
+		0000000000000000000000000000000000000000000000000000000000000006
+		0000000000000000000000000000000000000000000000000000000000000007"
+}

libs/ethabi/src/token/lenient.rs

+use token::{Tokenizer, StrictTokenizer};
+use util::{pad_u32, pad_i32};
+use errors::Error;
+
+/// Tries to parse string as a token. Does not require string to clearly represent the value.
+pub struct LenientTokenizer;
+
+impl Tokenizer for LenientTokenizer {
+	fn tokenize_address(value: &str) -> Result<[u8; 20], Error> {
+		StrictTokenizer::tokenize_address(value)
+	}
+
+	fn tokenize_string(value: &str) -> Result<String, Error> {
+		StrictTokenizer::tokenize_string(value)
+	}
+
+	fn tokenize_bool(value: &str) -> Result<bool, Error> {
+		StrictTokenizer::tokenize_bool(value)
+	}
+
+	fn tokenize_bytes(value: &str) -> Result<Vec<u8>, Error> {
+		StrictTokenizer::tokenize_bytes(value)
+	}
+
+	fn tokenize_fixed_bytes(value: &str, len: usize) -> Result<Vec<u8>, Error> {
+		StrictTokenizer::tokenize_fixed_bytes(value, len)
+	}
+
+	fn tokenize_uint(value: &str) -> Result<[u8; 32], Error> {
+		let result = StrictTokenizer::tokenize_uint(value);
+		if result.is_ok() {
+			return result;
+		}
+
+		let uint = try!(u32::from_str_radix(value, 10));
+		Ok(pad_u32(uint))
+	}
+
+	fn tokenize_int(value: &str) -> Result<[u8; 32], Error> {
+		let result = StrictTokenizer::tokenize_int(value);
+		if result.is_ok() {
+			return result;
+		}
+
+		let int = try!(i32::from_str_radix(value, 10));
+		Ok(pad_i32(int))
+	}
+}

libs/ethabi/src/token/mod.rs

+//! ABI param and parsing for it.
+
+mod lenient;
+mod strict;
+mod token;
+
+use {ParamType, Error, ErrorKind, ResultExt};
+pub use self::lenient::LenientTokenizer;
+pub use self::strict::StrictTokenizer;
+pub use self::token::Token;
+
+/// This trait should be used to parse string values as tokens.
+pub trait Tokenizer {
+	/// Tries to parse a string as a token of given type.
+	fn tokenize(param: &ParamType, value: &str) -> Result<Token, Error> {
+		match *param {
+			ParamType::Address => Self::tokenize_address(value).map(|a| Token::Address(a.into())),
+			ParamType::String => Self::tokenize_string(value).map(Token::String),
+			ParamType::Bool => Self::tokenize_bool(value).map(Token::Bool),
+			ParamType::Bytes => Self::tokenize_bytes(value).map(Token::Bytes),
+			ParamType::FixedBytes(len) => Self::tokenize_fixed_bytes(value, len).map(Token::FixedBytes),
+			ParamType::Uint(_) => Self::tokenize_uint(value).map(Into::into).map(Token::Uint),
+			ParamType::Int(_) => Self::tokenize_int(value).map(Into::into).map(Token::Int),
+			ParamType::Array(ref p) => Self::tokenize_array(value, p).map(Token::Array),
+			ParamType::FixedArray(ref p, len) => Self::tokenize_fixed_array(value, p, len).map(Token::FixedArray),
+		}.chain_err(|| format!("Cannot parse {}", param))
+	}
+
+	/// Tries to parse a value as a vector of tokens of fixed size.
+	fn tokenize_fixed_array(value: &str, param: &ParamType, len: usize) -> Result<Vec<Token>, Error> {
+		let result = try!(Self::tokenize_array(value, param));
+		match result.len() == len {
+			true => Ok(result),
+			false => Err(ErrorKind::InvalidData.into()),
+		}
+	}
+
+	/// Tries to parse a value as a vector of tokens.
+	fn tokenize_array(value: &str, param: &ParamType) -> Result<Vec<Token>, Error> {
+		if !value.starts_with('[') || !value.ends_with(']') {
+			return Err(ErrorKind::InvalidData.into());
+		}
+
+		if value.chars().count() == 2 {
+			return Ok(vec![]);
+		}
+
+		let mut result = vec![];
+		let mut nested = 0isize;
+		let mut ignore = false;
+		let mut last_item = 1;
+		for (i, ch) in value.chars().enumerate() {
+			match ch {
+				'[' if ignore == false => {
+					nested += 1;
+				},
+				']' if ignore == false => {
+					nested -= 1;
+					if nested < 0 {
+						return Err(ErrorKind::InvalidData.into());
+					} else if nested == 0 {
+						let sub = &value[last_item..i];
+						let token = try!(Self::tokenize(param, sub));
+						result.push(token);
+						last_item = i + 1;
+					}
+				},
+				'"' => {
+					ignore = !ignore;
+				},
+				',' if nested == 1 && ignore == false => {
+					let sub = &value[last_item..i];
+					let token = try!(Self::tokenize(param, sub));
+					result.push(token);
+					last_item = i + 1;
+				},
+				_ => ()
+			}
+		}
+
+		if ignore {
+			return Err(ErrorKind::InvalidData.into());
+		}
+
+		Ok(result)
+	}
+
+	/// Tries to parse a value as an address.
+	fn tokenize_address(value: &str) -> Result<[u8; 20], Error>;
+
+	/// Tries to parse a value as a string.
+	fn tokenize_string(value: &str) -> Result<String, Error>;
+
+	/// Tries to parse a value as a bool.
+	fn tokenize_bool(value: &str) -> Result<bool, Error>;
+
+	/// Tries to parse a value as bytes.
+	fn tokenize_bytes(value: &str) -> Result<Vec<u8>, Error>;
+
+	/// Tries to parse a value as bytes.
+	fn tokenize_fixed_bytes(value: &str, len: usize) -> Result<Vec<u8>, Error>;
+
+	/// Tries to parse a value as unsigned integer.
+	fn tokenize_uint(value: &str) -> Result<[u8; 32], Error>;
+
+	/// Tries to parse a value as signed integer.
+	fn tokenize_int(value: &str) -> Result<[u8; 32], Error>;
+}
+
+#[cfg(test)]
+mod test {
+	use super::{LenientTokenizer, Tokenizer, ParamType};
+	#[test]
+	fn single_quoted_in_array_must_error() {
+		assert!(LenientTokenizer::tokenize_array("[1,\"0,false]", &ParamType::Bool).is_err());
+		assert!(LenientTokenizer::tokenize_array("[false\"]", &ParamType::Bool).is_err());
+		assert!(LenientTokenizer::tokenize_array("[1,false\"]", &ParamType::Bool).is_err());
+		assert!(LenientTokenizer::tokenize_array("[1,\"0\",false]", &ParamType::Bool).is_err());
+		assert!(LenientTokenizer::tokenize_array("[1,0]", &ParamType::Bool).is_ok());
+	}
+}

libs/ethabi/src/token/strict.rs

+use hex::FromHex;
+use token::Tokenizer;
+use errors::{Error, ErrorKind};
+
+/// Tries to parse string as a token. Require string to clearly represent the value.
+pub struct StrictTokenizer;
+
+impl Tokenizer for StrictTokenizer {
+	fn tokenize_address(value: &str) -> Result<[u8; 20], Error> {
+		let hex : Vec<u8> = try!(value.from_hex());
+		match hex.len() == 20 {
+			false => Err(ErrorKind::InvalidData.into()),
+			true => {
+				let mut address = [0u8; 20];
+				address.copy_from_slice(&hex);
+				Ok(address)
+			}
+		}
+	}
+
+	fn tokenize_string(value: &str) -> Result<String, Error> {
+		Ok(value.to_owned())
+	}
+
+	fn tokenize_bool(value: &str) -> Result<bool, Error> {
+		match value {
+			"true" | "1" => Ok(true),
+			"false" | "0" => Ok(false),
+			_ => Err(ErrorKind::InvalidData.into()),
+		}
+	}
+
+	fn tokenize_bytes(value: &str) -> Result<Vec<u8>, Error> {
+		let hex = try!(value.from_hex());
+		Ok(hex)
+	}
+
+	fn tokenize_fixed_bytes(value: &str, len: usize) -> Result<Vec<u8>, Error> {
+		let hex : Vec<u8> = try!(value.from_hex());
+		match hex.len() == len {
+			true => Ok(hex),
+			false => Err(ErrorKind::InvalidData.into()),
+		}
+	}
+
+	fn tokenize_uint(value: &str) -> Result<[u8; 32], Error> {
+		let hex : Vec<u8> = try!(value.from_hex());
+		match hex.len() == 32 {
+			true => {
+				let mut uint = [0u8; 32];
+				uint.copy_from_slice(&hex);
+				Ok(uint)
+			},
+			false => Err(ErrorKind::InvalidData.into())
+		}
+	}
+
+	fn tokenize_int(value: &str) -> Result<[u8; 32], Error> {
+		let hex : Vec<u8> = try!(value.from_hex());
+		match hex.len() == 32 {
+			true => {
+				let mut int = [0u8; 32];
+				int.copy_from_slice(&hex);
+				Ok(int)
+			},
+			false => Err(ErrorKind::InvalidData.into())
+		}
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use ParamType;
+	use token::{Token, Tokenizer, StrictTokenizer};
+
+	#[test]
+	fn tokenize_address() {
+		assert_eq!(StrictTokenizer::tokenize(&ParamType::Address, "1111111111111111111111111111111111111111").unwrap(), Token::Address([0x11u8; 20].into()));
+		assert_eq!(StrictTokenizer::tokenize(&ParamType::Address, "2222222222222222222222222222222222222222").unwrap(), Token::Address([0x22u8; 20].into()));
+	}
+
+	#[test]
+	fn tokenize_string() {
+		assert_eq!(StrictTokenizer::tokenize(&ParamType::String, "gavofyork").unwrap(), Token::String("gavofyork".to_owned()));
+		assert_eq!(StrictTokenizer::tokenize(&ParamType::String, "hello").unwrap(), Token::String("hello".to_owned()));
+	}
+
+	#[test]
+	fn tokenize_bool() {
+		assert_eq!(StrictTokenizer::tokenize(&ParamType::Bool, "true").unwrap(), Token::Bool(true));
+		assert_eq!(StrictTokenizer::tokenize(&ParamType::Bool, "1").unwrap(), Token::Bool(true));
+		assert_eq!(StrictTokenizer::tokenize(&ParamType::Bool, "false").unwrap(), Token::Bool(false));
+		assert_eq!(StrictTokenizer::tokenize(&ParamType::Bool, "0").unwrap(), Token::Bool(false));
+	}
+
+	#[test]
+	fn tokenize_bytes() {
+		assert_eq!(StrictTokenizer::tokenize(&ParamType::Bytes, "123456").unwrap(), Token::Bytes(vec![0x12, 0x34, 0x56]));
+		assert_eq!(StrictTokenizer::tokenize(&ParamType::Bytes, "0017").unwrap(), Token::Bytes(vec![0x00, 0x17]));
+	}
+
+	#[test]
+	fn tokenize_fixed_bytes() {
+		assert_eq!(StrictTokenizer::tokenize(&ParamType::FixedBytes(3), "123456").unwrap(), Token::FixedBytes(vec![0x12, 0x34, 0x56]));
+		assert_eq!(StrictTokenizer::tokenize(&ParamType::FixedBytes(2), "0017").unwrap(), Token::FixedBytes(vec![0x00, 0x17]));
+	}
+
+	#[test]
+	fn tokenize_uint() {
+		assert_eq!(
+			StrictTokenizer::tokenize(&ParamType::Uint(256), "1111111111111111111111111111111111111111111111111111111111111111").unwrap(),
+			Token::Uint([0x11u8; 32].into())
+		);
+
+		assert_eq!(
+			StrictTokenizer::tokenize(&ParamType::Uint(256), "2222222222222222222222222222222222222222222222222222222222222222").unwrap(),
+			Token::Uint([0x22u8; 32].into())
+		);
+	}
+
+	#[test]
+	fn tokenize_int() {
+		assert_eq!(
+			StrictTokenizer::tokenize(&ParamType::Int(256), "1111111111111111111111111111111111111111111111111111111111111111").unwrap(),
+			Token::Int([0x11u8; 32].into())
+		);
+
+		assert_eq!(
+			StrictTokenizer::tokenize(&ParamType::Int(256), "2222222222222222222222222222222222222222222222222222222222222222").unwrap(),
+			Token::Int([0x22u8; 32].into())
+		);
+	}
+
+	#[test]
+	fn tokenize_empty_array() {
+		assert_eq!(
+			StrictTokenizer::tokenize(&ParamType::Array(Box::new(ParamType::Bool)), "[]").unwrap(),
+			Token::Array(vec![])
+		);
+	}
+
+	#[test]
+	fn tokenize_bool_array() {
+		assert_eq!(
+			StrictTokenizer::tokenize(&ParamType::Array(Box::new(ParamType::Bool)), "[true,1,0,false]").unwrap(),
+			Token::Array(vec![Token::Bool(true), Token::Bool(true), Token::Bool(false), Token::Bool(false)])
+		);
+	}
+
+	#[test]
+	fn tokenize_bool_array_of_arrays() {
+		assert_eq!(
+			StrictTokenizer::tokenize(&ParamType::Array(Box::new(ParamType::Array(Box::new(ParamType::Bool)))), "[[true,1,0],[false]]").unwrap(),
+			Token::Array(vec![
+				Token::Array(vec![Token::Bool(true), Token::Bool(true), Token::Bool(false)]),
+				Token::Array(vec![Token::Bool(false)])
+			])
+		);
+	}
+}
+

libs/ethabi/src/token/token.rs

+//! Ethereum ABI params.
+use std::fmt;
+use hex::ToHex;
+use {ParamType, Address, FixedBytes, Bytes, Uint};
+
+/// Ethereum ABI params.
+#[derive(Debug, PartialEq, Clone)]
+pub enum Token {
+	/// Address.
+	///
+	/// solidity name: address
+	/// Encoded to left padded [0u8; 32].
+	Address(Address),
+	/// Vector of bytes with known size.
+	///
+	/// solidity name eg.: bytes8, bytes32, bytes64, bytes1024
+	/// Encoded to right padded [0u8; ((N + 31) / 32) * 32].
+	FixedBytes(FixedBytes),
+	/// Vector of bytes of unknown size.
+	///
+	/// solidity name: bytes
+	/// Encoded in two parts.
+	/// Init part: offset of 'closing part`.
+	/// Closing part: encoded length followed by encoded right padded bytes.
+	Bytes(Bytes),
+	/// Signed integer.
+	///
+	/// solidity name: int
+	Int(Uint),
+	/// Unisnged integer.
+	///
+	/// solidity name: uint
+	Uint(Uint),
+	/// Boolean value.
+	///
+	/// solidity name: bool
+	/// Encoded as left padded [0u8; 32], where last bit represents boolean value.
+	Bool(bool),
+	/// String.
+	///
+	/// solidity name: string
+	/// Encoded in the same way as bytes. Must be utf8 compliant.
+	String(String),
+	/// Array with known size.
+	///
+	/// solidity name eg.: int[3], bool[3], address[][8]
+	/// Encoding of array is equal to encoding of consecutive elements of array.
+	FixedArray(Vec<Token>),
+	/// Array of params with unknown size.
+	///
+	/// solidity name eg. int[], bool[], address[5][]
+	Array(Vec<Token>),
+}
+
+impl fmt::Display for Token {
+	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+		match *self {
+			Token::Bool(b) => write!(f, "{}", b),
+			Token::String(ref s) => write!(f, "{}", s),
+			Token::Address(ref a) => write!(f, "{:x}", a),
+			Token::Bytes(ref bytes) | Token::FixedBytes(ref bytes) => write!(f, "{}", bytes.to_hex::<String>()),
+			Token::Uint(ref i) | Token::Int(ref i) => write!(f, "{:x}", i),
+			Token::Array(ref arr) | Token::FixedArray(ref arr) => {
+				let s = arr.iter()
+					.map(|ref t| format!("{}", t))
+					.collect::<Vec<String>>()
+					.join(",");
+
+				write!(f, "[{}]", s)
+			}
+		}
+	}
+}
+
+impl Token {
+	/// Returns whether this token is dynamic
+	pub fn is_dynamic(&self) -> bool {
+		match self {
+			Token::Bytes(_) | Token::String(_) | Token::Array(_) => true,
+			Token::FixedArray(ref tokens) => tokens.iter().any(|ref token| token.is_dynamic()),
+			_ => false
+		}
+	}
+
+	/// Check whether the type of the token matches the given parameter type.
+	///
+	/// Numeric types (`Int` and `Uint`) type check if the size of the token
+	/// type is of greater or equal size than the provided parameter type.
+	pub fn type_check(&self, param_type: &ParamType) -> bool {
+		match *self {
+			Token::Address(_) => *param_type == ParamType::Address,
+			Token::Bytes(_) => *param_type == ParamType::Bytes,
+			Token::Int(_) =>
+				if let ParamType::Int(_) = *param_type {
+					true
+				} else {
+					false
+				},
+			Token::Uint(_) =>
+				if let ParamType::Uint(_) = *param_type {
+					true
+				} else {
+					false
+				},
+			Token::Bool(_) => *param_type == ParamType::Bool,
+			Token::String(_) => *param_type == ParamType::String,
+			Token::FixedBytes(ref bytes) =>
+				if let ParamType::FixedBytes(size) = *param_type {
+					size >= bytes.len()
+				} else {
+					false
+				},
+			Token::Array(ref tokens) =>
+				if let ParamType::Array(ref param_type) = *param_type {
+					tokens.iter().all(|t| t.type_check(param_type))
+				} else {
+					false
+				},
+			Token::FixedArray(ref tokens) =>
+				if let ParamType::FixedArray(ref param_type, size) = *param_type {
+					size == tokens.len() && tokens.iter().all(|t| t.type_check(param_type))
+				} else {
+					false
+				},
+		}
+	}
+
+	/// Converts token to...
+	pub fn to_address(self) -> Option<Address> {
+		match self {
+			Token::Address(address) => Some(address),
+			_ => None,
+		}
+	}
+
+	/// Converts token to...
+	pub fn to_fixed_bytes(self) -> Option<Vec<u8>> {
+		match self {
+			Token::FixedBytes(bytes) => Some(bytes),
+			_ => None,
+		}
+	}
+
+	/// Converts token to...
+	pub fn to_bytes(self) -> Option<Vec<u8>> {
+		match self {
+			Token::Bytes(bytes) => Some(bytes),
+			_ => None,
+		}
+	}
+
+	/// Converts token to...
+	pub fn to_int(self) -> Option<Uint> {
+		match self {
+			Token::Int(int) => Some(int),
+			_ => None,
+		}
+	}
+
+	/// Converts token to...
+	pub fn to_uint(self) -> Option<Uint> {
+		match self {
+			Token::Uint(uint) => Some(uint),
+			_ => None,
+		}
+	}
+
+	/// Converts token to...
+	pub fn to_bool(self) -> Option<bool> {
+		match self {
+			Token::Bool(b) => Some(b),
+			_ => None,
+		}
+	}
+
+	/// Converts token to...
+	pub fn to_string(self) -> Option<String> {
+		match self {
+			Token::String(s) => Some(s),
+			_ => None,
+		}
+	}
+
+	/// Converts token to...
+	pub fn to_fixed_array(self) -> Option<Vec<Token>> {
+		match self {
+			Token::FixedArray(arr) => Some(arr),
+			_ => None,
+		}
+	}
+
+	/// Converts token to...
+	pub fn to_array(self) -> Option<Vec<Token>> {
+		match self {
+			Token::Array(arr) => Some(arr),
+			_ => None,
+		}
+	}
+
+	/// Check if all the types of the tokens match the given parameter types.
+	pub fn types_check(tokens: &[Token], param_types: &[ParamType]) -> bool {
+		param_types.len() == tokens.len() && {
+			param_types.iter().zip(tokens).all(|(param_type, token)| {
+				token.type_check(param_type)
+			})
+		}
+	}
+}
+
+
+#[cfg(test)]
+mod tests {
+	use {Token, ParamType};
+
+	#[test]
+	fn test_type_check() {
+		fn assert_type_check(tokens: Vec<Token>, param_types: Vec<ParamType>) {
+			assert!(Token::types_check(&tokens, &param_types))
+		}
+
+		fn assert_not_type_check(tokens: Vec<Token>, param_types: Vec<ParamType>) {
+			assert!(!Token::types_check(&tokens, &param_types))
+		}
+
+		assert_type_check(vec![Token::Uint(0.into()), Token::Bool(false)], vec![ParamType::Uint(256), ParamType::Bool]);
+		assert_type_check(vec![Token::Uint(0.into()), Token::Bool(false)], vec![ParamType::Uint(32), ParamType::Bool]);
+
+		assert_not_type_check(vec![Token::Uint(0.into())], vec![ParamType::Uint(32), ParamType::Bool]);
+		assert_not_type_check(vec![Token::Uint(0.into()), Token::Bool(false)], vec![ParamType::Uint(32)]);
+		assert_not_type_check(vec![Token::Bool(false), Token::Uint(0.into())], vec![ParamType::Uint(32), ParamType::Bool]);
+
+		assert_type_check(vec![Token::FixedBytes(vec![0, 0, 0, 0])], vec![ParamType::FixedBytes(4)]);
+		assert_type_check(vec![Token::FixedBytes(vec![0, 0, 0])], vec![ParamType::FixedBytes(4)]);
+		assert_not_type_check(vec![Token::FixedBytes(vec![0, 0, 0, 0])], vec![ParamType::FixedBytes(3)]);
+
+		assert_type_check(vec![Token::Array(vec![Token::Bool(false), Token::Bool(true)])], vec![ParamType::Array(Box::new(ParamType::Bool))]);
+		assert_not_type_check(vec![Token::Array(vec![Token::Bool(false), Token::Uint(0.into())])], vec![ParamType::Array(Box::new(ParamType::Bool))]);
+		assert_not_type_check(vec![Token::Array(vec![Token::Bool(false), Token::Bool(true)])], vec![ParamType::Array(Box::new(ParamType::Address))]);
+
+		assert_type_check(vec![Token::FixedArray(vec![Token::Bool(false), Token::Bool(true)])], vec![ParamType::FixedArray(Box::new(ParamType::Bool), 2)]);
+		assert_not_type_check(vec![Token::FixedArray(vec![Token::Bool(false), Token::Bool(true)])], vec![ParamType::FixedArray(Box::new(ParamType::Bool), 3)]);
+		assert_not_type_check(vec![Token::FixedArray(vec![Token::Bool(false), Token::Uint(0.into())])], vec![ParamType::FixedArray(Box::new(ParamType::Bool), 2)]);
+		assert_not_type_check(vec![Token::FixedArray(vec![Token::Bool(false), Token::Bool(true)])], vec![ParamType::FixedArray(Box::new(ParamType::Address), 2)]);
+	}
+
+	#[test]
+	fn test_is_dynamic() {
+		assert_eq!(Token::Address("0000000000000000000000000000000000000000".parse().unwrap()).is_dynamic(), false);
+		assert_eq!(Token::Bytes(vec![0, 0, 0, 0]).is_dynamic(), true);
+		assert_eq!(Token::FixedBytes(vec![0, 0, 0, 0]).is_dynamic(), false);
+		assert_eq!(Token::Uint(0.into()).is_dynamic(), false);
+		assert_eq!(Token::Int(0.into()).is_dynamic(), false);
+		assert_eq!(Token::Bool(false).is_dynamic(), false);
+		assert_eq!(Token::String("".into()).is_dynamic(), true);
+		assert_eq!(Token::Array(vec![Token::Bool(false)]).is_dynamic(), true);
+		assert_eq!(Token::FixedArray(vec![Token::Uint(0.into())]).is_dynamic(), false);
+		assert_eq!(Token::FixedArray(vec![Token::String("".into())]).is_dynamic(), true);
+		assert_eq!(Token::FixedArray(vec![Token::Array(vec![Token::Bool(false)])]).is_dynamic(), true);
+	}
+}

libs/ethabi/src/util.rs

+//! Utils used by different modules.
+
+use {Word, Error, ErrorKind};
+
+/// Convers vector of bytes with len equal n * 32, to a vector of slices.
+pub fn slice_data(data: &[u8]) -> Result<Vec<Word>, Error> {
+	if data.len() % 32 != 0 {
+		return Err(ErrorKind::InvalidData.into());
+	}
+
+	let times = data.len() / 32;
+	let mut result = Vec::with_capacity(times);
+	for i in 0..times {
+		let mut slice = [0u8; 32];
+		let offset = 32 * i;
+		slice.copy_from_slice(&data[offset..offset + 32]);
+		result.push(slice);
+	}
+	Ok(result)
+}
+
+/// Converts u32 to right aligned array of 32 bytes.
+pub fn pad_u32(value: u32) -> Word {
+	let mut padded = [0u8; 32];
+	padded[28] = (value >> 24) as u8;
+	padded[29] = (value >> 16) as u8;
+	padded[30] = (value >> 8) as u8;
+	padded[31] = value as u8;
+	padded
+}
+
+/// Converts i32 to right aligned array of 32 bytes.
+pub fn pad_i32(value: i32) -> Word {
+	if value >= 0 {
+		return pad_u32(value as u32);
+	}
+
+	let mut padded = [0xffu8; 32];
+	padded[28] = (value >> 24) as u8;
+	padded[29] = (value >> 16) as u8;
+	padded[30] = (value >> 8) as u8;
+	padded[31] = value as u8;
+	padded
+}
+
+#[cfg(test)]
+mod tests {
+	use super::{pad_u32, pad_i32};
+
+	#[test]
+	fn test_pad_u32() {
+		// this will fail if endianess is not supported
+        assert_eq!(pad_u32(0).to_vec(), hex!("0000000000000000000000000000000000000000000000000000000000000000").to_vec());
+        assert_eq!(pad_u32(1).to_vec(), hex!("0000000000000000000000000000000000000000000000000000000000000001").to_vec());
+        assert_eq!(pad_u32(0x100).to_vec(), hex!("0000000000000000000000000000000000000000000000000000000000000100").to_vec());
+        assert_eq!(pad_u32(0xffffffff).to_vec(), hex!("00000000000000000000000000000000000000000000000000000000ffffffff").to_vec());
+	}
+
+	#[test]
+	fn test_i32() {
+		assert_eq!(pad_i32(0).to_vec(), hex!("0000000000000000000000000000000000000000000000000000000000000000").to_vec());
+		assert_eq!(pad_i32(-1).to_vec(), hex!("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").to_vec());
+		assert_eq!(pad_i32(-2).to_vec(), hex!("fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffe").to_vec());
+		assert_eq!(pad_i32(-256).to_vec(), hex!("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff00").to_vec());
+	}
+}

src/bignum.rs

+//! The bignum system library.
+use crate::types::Uint256;
+
+/// The low-level interface to the system library. Use the wrapper functions unless you know what
+/// you're doing.
+pub mod native {
+    extern "C" {
+        pub fn bignum_mul256(a: *const u32, b: *const u32, ret: *const u32);
+        pub fn bignum_umulmod256(a: *const u32, b: *const u32, modulo: *const u32, ret: *const u32);
+    }
+}
+
+/// Unsigned 256-bit multiplication.
+pub fn mul256(a: &Uint256, b: &Uint256) -> Uint256 {
+    let mut ret = Uint256::default();
+
+    unsafe {
+        native::bignum_mul256(
+            a.bytes.as_ptr() as *const u32,
+            b.bytes.as_ptr() as *const u32,
+            ret.bytes.as_mut_ptr() as *const u32,
+        )
+    }
+
+    ret
+}
+
+/// Unsigned 256-bit multiplication modulo n.
+pub fn umulmod256(a: &Uint256, b: &Uint256, modulo: &Uint256) -> Uint256 {
+    let mut ret = Uint256::default();
+
+    unsafe {
+        native::bignum_umulmod256(
+            a.bytes.as_ptr() as *const u32,
+            b.bytes.as_ptr() as *const u32,
+            modulo.bytes.as_ptr() as *const u32,
+            ret.bytes.as_mut_ptr() as *const u32,
+        )
+    }
+
+    ret
+}

src/convert.rs

+//! Basic type conversion traits. Unlike the native standard library, `U: From<T>` does not yet
+//! imply `T: Into<U>`.
+
+use super::*;
+
+pub trait From<T>: Sized {
+    fn from(_: T) -> Self;
+}
+
+pub trait Into<T>: Sized {
+    fn from(self) -> T;
+}

src/debug.rs

+//! The native debug interface exposed to the ewasm contract. These functions are for testing
+//! purposes only. On a live VM, any bytecode trying to import these symbols will be rejected.
+
+use crate::types::StorageKey;
+
+/// The native interface for debugging functions.
+mod native {
+    extern "C" {
+        pub fn debug_print32(value: u32);
+        pub fn debug_print64(value: u64);
+        pub fn debug_printMem(offset: *const u32, len: u32);
+        pub fn debug_printMemHex(offset: *const u32, len: u32);
+        pub fn debug_printStorage(pathOffset: *const u32);
+        pub fn debug_printStorageHex(pathOffset: *const u32);
+    }
+}
+
+/// Prints an unsigned 32-bit int.
+pub fn print32(value: u32) {
+    unsafe { native::debug_print32(value) }
+}
+
+/// Prints an unsigned 64-bit int.
+pub fn print64(value: u64) {
+    unsafe { native::debug_print64(value) }
+}
+
+/// Prints the contents of a slice.
+pub fn print_mem(slice: &[u8]) {
+    unsafe { native::debug_printMem(slice.as_ptr() as *const u32, slice.len() as u32) }
+}
+
+/// Prints the contents of a slice in hexadecimal format.
+pub fn print_mem_hex(slice: &[u8]) {
+    unsafe { native::debug_printMemHex(slice.as_ptr() as *const u32, slice.len() as u32) }
+}
+
+/// Prints the value of a storage key.
+pub fn print_storage(key: &StorageKey) {
+    unsafe { native::debug_printStorage(key.bytes.as_ptr() as *const u32) }
+}
+
+/// Prints the value of a storage key in hexadecimal format.
+pub fn print_storage_hex(key: &StorageKey) {
+    unsafe { native::debug_printStorageHex(key.bytes.as_ptr() as *const u32) }
+}

src/lib.rs

+//! ewasm_api is a library used to interface with Ethereum's EEI in [Ewasm](https://github.com/ewasm/design), a set of enhancements to
+//! the Ethereum smart contract platform.
+//! ewasm_api exposes both a set of unsafe "native" functions representing the actual EEI
+//! functions, and a set of safe wrappers around them. It is recommended not to use the native
+//! functions as they do not perform bounds-checking.
+//!
+//! To use ewasm_api, simply include it as a dependency in your project.
+//! ewasm_api can be built with various feature sets:
+//! - `default`: Builds with `wee_alloc` as the global allocator and with the Rust standard
+//! library.
+//! - `qimalloc`: Builds with [qimalloc](https://github.com/wasmx/qimalloc) as the global
+//! allocator.
+//! - `debug`: Exposes the debugging interface.
+//! - `experimental`: Exposes the experimental bignum system library API.
+//!
+//! # Examples
+//! ```ignore
+//! extern crate ewasm_api;
+//!
+//! use ewasm_api::{Hash, block_hash, finish_data};
+//!
+//! #[cfg(target_arch = "wasm32")]
+//! #[no_mangle]
+//! pub extern "C" fn main() {
+//!     let a: Hash = block_hash(1);
+//!     finish_data(&a.bytes);
+//! }
+//! ```
+
+#[macro_use]
+extern crate cfg_if;
+
+cfg_if! {
+    if #[cfg(feature = "wee_alloc")] {
+        extern crate wee_alloc;
+        #[global_allocator]
+        static ALLOC: wee_alloc::WeeAlloc = wee_alloc::WeeAlloc::INIT;
+    } else if #[cfg(feature = "qimalloc")] {
+        extern crate qimalloc;
+        #[global_allocator]
+        static ALLOC: qimalloc::QIMalloc = qimalloc::QIMalloc::INIT;
+    }
+}
+
+mod native;
+mod utils;
+
+pub extern crate ethabi as metavmabi;
+
+//pub extern crate rustc_hex;
+pub mod metavm;
+pub mod types;
+
+#[cfg(feature = "debug")]
+pub mod debug;
+
+#[cfg(feature = "experimental")]
+pub mod bignum;
+
+#[cfg(not(feature = "std"))]
+pub mod convert;
+
+#[cfg(feature = "std")]
+use std::vec::Vec;
+
+use types::*;
+use utils::*;
+
+/// Re-export of all the basic features.
+pub mod prelude {
+    pub use crate::*;
+
+    pub use crate::types::*;
+
+    #[cfg(not(feature = "std"))]
+    pub use crate::convert::*;
+
+    #[cfg(feature = "debug")]
+    pub use crate::debug;
+
+    #[cfg(feature = "experimental")]
+    pub use crate::bignum;
+}
+
+/// Enum representing an error code for EEI calls. Currently used by `codeCopy`, `callDataCopy`,
+/// `externalCodeCopy`, and `returnDataCopy`.
+pub enum Error {
+    OutOfBoundsCopy,
+}
+
+/// Enum describing the result of a call. Used by `call`, `callCode`, `callDelegate`, and
+/// `callStatic`.
+pub enum CallResult {
+    Successful,
+    Failure,
+    Revert,
+    Unknown,
+}
+
+/// Enum describing the result of `create`. On success, the data contained is the address of the
+/// newly created contract.
+pub enum CreateResult {
+    Successful(Address),
+    Failure,
+    Revert,
+    Unknown,
+}
+
+/// Subtracts the given amount from the VM's gas counter. This is usually injected by the metering
+/// contract at deployment time, and hence is unneeded in most cases.
+pub fn consume_gas(amount: u64) {
+    unsafe {
+        native::ethereum_useGas(amount);
+    }
+}
+
+/// Returns the gas left in the current call.
+pub fn gas_left() -> u64 {
+    unsafe { native::ethereum_getGasLeft() }
+}
+
+/// Returns the executing address.
+pub fn current_address() -> Address {
+    let mut ret = Address::default();
+
+    unsafe {
+        native::ethereum_getAddress(ret.bytes.as_mut_ptr() as *const u32);
+    }
+
+    ret
+}
+
+/// Returns the balance of the address given.
+pub fn external_balance(address: &Address) -> EtherValue {
+    let mut ret = EtherValue::default();
+
+    unsafe {
+        native::ethereum_getExternalBalance(
+            address.bytes.as_ptr() as *const u32,
+            ret.bytes.as_mut_ptr() as *const u32,
+        );
+    }
+
+    ret
+}
+
+/// Returns the beneficiary address for the block this transaction is in (current block)
+pub fn block_coinbase() -> Address {
+    let mut ret = Address::default();
+
+    unsafe {
+        native::ethereum_getBlockCoinbase(ret.bytes.as_mut_ptr() as *const u32);
+    }
+
+    ret
+}
+
+/// Returns the difficulty of the most recent block.
+pub fn block_difficulty() -> Difficulty {
+    let mut ret = Difficulty::default();
+
+    unsafe {
+        native::ethereum_getBlockDifficulty(ret.bytes.as_mut_ptr() as *const u32);
+    }
+
+    ret
+}
+
+/// Returns the gas limit of the most recent block.
+pub fn block_gas_limit() -> u64 {
+    unsafe { native::ethereum_getBlockGasLimit() }
+}
+
+/// Returns the hash of the `number`th most recent block.
+pub fn block_hash(number: u64) -> Hash {
+    let mut ret = Hash::default();
+
+    unsafe {
+        native::ethereum_getBlockHash(number, ret.bytes.as_mut_ptr() as *const u32);
+    }
+
+    ret
+}
+
+/// Returns the number of the most recent block.
+pub fn block_number() -> u64 {
+    unsafe { native::ethereum_getBlockNumber() }
+}
+
+/// Returns the timestamp of the most recent block.
+pub fn block_timestamp() -> u64 {
+    unsafe { native::ethereum_getBlockTimestamp() }
+}
+
+/// Returns the gas price of the currently executing call.
+pub fn tx_gas_price() -> EtherValue {
+    let mut ret = EtherValue::default();
+
+    unsafe {
+        native::ethereum_getTxGasPrice(ret.bytes.as_mut_ptr() as *const u32);
+    }
+
+    ret
+}
+
+/// Returns the address of the original transaction sender.
+pub fn tx_origin() -> Address {
+    let mut ret = Address::default();
+
+    unsafe {
+        native::ethereum_getTxOrigin(ret.bytes.as_mut_ptr() as *const u32);
+    }
+
+    ret
+}
+
+/// Appends log data to the transaction receipt, with a variable number of topics.
+fn log(
+    data: &[u8],
+    topic_count: usize,
+    topic1: *const u8,
+    topic2: *const u8,
+    topic3: *const u8,
+    topic4: *const u8,
+) {
+    unsafe {
+        native::ethereum_log(
+            data.as_ptr() as *const u32,
+            data.len() as u32,
+            topic_count as u32,
+            topic1 as *const u32,
+            topic2 as *const u32,
+            topic3 as *const u32,
+            topic4 as *const u32,
+        );
+    }
+}
+
+/// Appends log data without a topic.
+pub fn log0(data: &[u8]) {
+    log(
+        data,
+        0,
+        0 as *const u8,
+        0 as *const u8,
+        0 as *const u8,
+        0 as *const u8,
+    )
+}
+
+/// Appends log data with one topic.
+pub fn log1(data: &[u8], topic1: &LogTopic) {
+    log(
+        data,
+        1,
+        topic1.bytes.as_ptr() as *const u8,
+        0 as *const u8,
+        0 as *const u8,
+        0 as *const u8,
+    )
+}
+
+/// Appends log data with two topics.
+pub fn log2(data: &[u8], topic1: &LogTopic, topic2: &LogTopic) {
+    log(
+        data,
+        2,
+        topic1.bytes.as_ptr() as *const u8,
+        topic2.bytes.as_ptr() as *const u8,
+        0 as *const u8,
+        0 as *const u8,
+    )
+}
+
+/// Appends log data with three topics.
+pub fn log3(data: &[u8], topic1: &LogTopic, topic2: &LogTopic, topic3: &LogTopic) {
+    log(
+        data,
+        3,
+        topic1.bytes.as_ptr() as *const u8,
+        topic2.bytes.as_ptr() as *const u8,
+        topic3.bytes.as_ptr() as *const u8,
+        0 as *const u8,
+    )
+}
+
+/// Appends log data with four topics.
+pub fn log4(
+    data: &[u8],
+    topic1: &LogTopic,
+    topic2: &LogTopic,
+    topic3: &LogTopic,
+    topic4: &LogTopic,
+) {
+    log(
+        data,
+        4,
+        topic1.bytes.as_ptr() as *const u8,
+        topic2.bytes.as_ptr() as *const u8,
+        topic3.bytes.as_ptr() as *const u8,
+        topic4.bytes.as_ptr() as *const u8,
+    )
+}
+
+/// Executes a standard call to the specified address with the given gas limit, ether value, and
+/// data.
+pub fn call_mutable(
+    gas_limit: u64,
+    address: &Address,
+    value: &EtherValue,
+    data: &[u8],
+) -> CallResult {
+    let ret = unsafe {
+        native::ethereum_call(
+            gas_limit,
+            address.bytes.as_ptr() as *const u32,
+            value.bytes.as_ptr() as *const u32,
+            data.as_ptr() as *const u32,
+            data.len() as u32,
+        )
+    };
+
+    match ret {
+        0 => CallResult::Successful,
+        1 => CallResult::Failure,
+        2 => CallResult::Revert,
+        _ => CallResult::Unknown,
+    }
+}
+
+/// Executes another account's code in the context of the caller.
+pub fn call_code(gas_limit: u64, address: &Address, value: &EtherValue, data: &[u8]) -> CallResult {
+    let ret = unsafe {
+        native::ethereum_callCode(
+            gas_limit,
+            address.bytes.as_ptr() as *const u32,
+            value.bytes.as_ptr() as *const u32,
+            data.as_ptr() as *const u32,
+            data.len() as u32,
+        )
+    };
+
+    match ret {
+        0 => CallResult::Successful,
+        1 => CallResult::Failure,
+        2 => CallResult::Revert,
+        _ => CallResult::Unknown,
+    }
+}
+
+/// Executes a call similar to `call_code`, but retaining the currently executing call's sender
+/// and value.
+pub fn call_delegate(gas_limit: u64, address: &Address, data: &[u8]) -> CallResult {
+    let ret = unsafe {
+        native::ethereum_callDelegate(
+            gas_limit,
+            address.bytes.as_ptr() as *const u32,
+            data.as_ptr() as *const u32,
+            data.len() as u32,
+        )
+    };
+
+    match ret {
+        0 => CallResult::Successful,
+        1 => CallResult::Failure,
+        2 => CallResult::Revert,
+        _ => CallResult::Unknown,
+    }
+}
+
+/// Executes a static call which cannot mutate the state.
+pub fn call_static(gas_limit: u64, address: &Address, data: &[u8]) -> CallResult {
+    let ret = unsafe {
+        native::ethereum_callStatic(
+            gas_limit,
+            address.bytes.as_ptr() as *const u32,
+            data.as_ptr() as *const u32,
+            data.len() as u32,
+        )
+    };
+
+    match ret {
+        0 => CallResult::Successful,
+        1 => CallResult::Failure,
+        2 => CallResult::Revert,
+        _ => CallResult::Unknown,
+    }
+}
+
+/// Creates a contract with the the given code, sending the specified ether value to its address.
+pub fn create(value: &EtherValue, data: &[u8]) -> CreateResult {
+    let mut address = Address::default();
+
+    let ret = unsafe {
+        native::ethereum_create(
+            value.bytes.as_ptr() as *const u32,
+            data.as_ptr() as *const u32,
+            data.len() as u32,
+            address.bytes.as_mut_ptr() as *const u32,
+        )
+    };
+
+    match ret {
+        0 => CreateResult::Successful(address),
+        1 => CreateResult::Failure,
+        2 => CreateResult::Revert,
+        _ => CreateResult::Unknown,
+    }
+}
+
+/// Executes callDataCopy, but does not check for overflow.
+pub fn unsafe_calldata_copy(from: usize, length: usize, ret: &mut [u8]) {
+    unsafe {
+        native::ethereum_callDataCopy(ret.as_mut_ptr() as *const u32, from as u32, length as u32);
+    }
+}
+
+#[cfg(feature = "std")]
+/// Returns a vector containing all data passed with the currently executing call.
+pub fn calldata_acquire() -> Vec<u8> {
+    let length = calldata_size();
+
+    let mut ret: Vec<u8> = unsafe_alloc_buffer(length);
+    unsafe_calldata_copy(0, length, &mut ret);
+    ret
+}
+
+/// Returns the segment of call data beginning at `from`, and continuing for `length` bytes.
+pub fn calldata_copy(from: usize, length: usize, ret: &mut [u8]) -> Result<(), Error> {
+    let size = calldata_size();
+
+    if (size < from) || ((size - from) < length) || (ret.len() < length) {
+        Err(Error::OutOfBoundsCopy)
+    } else {
+        unsafe_calldata_copy(from, length, ret);
+        Ok(())
+    }
+}
+
+/// Returns the length of the call data supplied with the currently executing call.
+pub fn calldata_size() -> usize {
+    unsafe { native::ethereum_getCallDataSize() as usize }
+}
+
+/// Returns the sender of the currently executing call.
+pub fn caller() -> Address {
+    let mut ret = Address::default();
+
+    unsafe {
+        native::ethereum_getCaller(ret.bytes.as_mut_ptr() as *const u32);
+    }
+
+    ret
+}
+
+/// Returns the value sent with the currently executing call.
+pub fn callvalue() -> EtherValue {
+    let mut ret = EtherValue::default();
+
+    unsafe {
+        native::ethereum_getCallValue(ret.bytes.as_mut_ptr() as *const u32);
+    }
+
+    ret
+}
+
+/// Executes codeCopy, but does not check for overflow.
+pub fn unsafe_code_copy(from: usize, length: usize, ret: &mut [u8]) {
+    unsafe {
+        native::ethereum_codeCopy(ret.as_mut_ptr() as *const u32, from as u32, length as u32);
+    }
+}
+
+#[cfg(feature = "std")]
+/// Returns the currently executing code.
+pub fn code_acquire() -> Vec<u8> {
+    let length = code_size();
+
+    let mut ret: Vec<u8> = unsafe_alloc_buffer(length);
+    unsafe_code_copy(0, length, &mut ret);
+    ret
+}
+
+/// Copies the segment of running code beginning at `from` and continuing for `length` bytes.
+pub fn code_copy(from: usize, length: usize, ret: &mut [u8]) -> Result<(), Error> {
+    let size = code_size();
+
+    if (size < from) || ((size - from) < length) || (ret.len() < length) {
+        Err(Error::OutOfBoundsCopy)
+    } else {
+        unsafe_code_copy(from, length, ret);
+        Ok(())
+    }
+}
+
+/// Returns the size of the currently executing code.
+pub fn code_size() -> usize {
+    unsafe { native::ethereum_getCodeSize() as usize }
+}
+
+/// Executes externalCodeCopy, but does not check for overflow.
+pub fn unsafe_external_code_copy(address: &Address, from: usize, length: usize, ret: &mut [u8]) {
+    unsafe {
+        native::ethereum_externalCodeCopy(
+            address.bytes.as_ptr() as *const u32,
+            ret.as_mut_ptr() as *const u32,
+            from as u32,
+            length as u32,
+        );
+    }
+}
+
+#[cfg(feature = "std")]
+/// Returns the code at the specified address.
+pub fn external_code_acquire(address: &Address) -> Vec<u8> {
+    let length = external_code_size(address);
+
+    let mut ret: Vec<u8> = unsafe_alloc_buffer(length);
+    unsafe_external_code_copy(address, 0, length, &mut ret);
+    ret
+}
+
+/// Returns the segment of code at `address` beginning at `from` and continuing for `length` bytes.
+pub fn external_code_copy(
+    address: &Address,
+    from: usize,
+    length: usize,
+    ret: &mut [u8],
+) -> Result<(), Error> {
+    let size = external_code_size(address);
+
+    if (size < from) || ((size - from) < length) || (ret.len() < length) {
+        Err(Error::OutOfBoundsCopy)
+    } else {
+        unsafe_external_code_copy(address, from, length, ret);
+        Ok(())
+    }
+}
+
+/// Returns the size of the code at the specified address.
+pub fn external_code_size(address: &Address) -> usize {
+    unsafe { native::ethereum_getExternalCodeSize(address.bytes.as_ptr() as *const u32) as usize }
+}
+
+/// Executes returnDataCopy, but does not check for overflow.
+pub fn unsafe_returndata_copy(from: usize, length: usize, ret: &mut [u8]) {
+    unsafe {
+        native::ethereum_returnDataCopy(ret.as_mut_ptr() as *const u32, from as u32, length as u32);
+    }
+}
+
+#[cfg(feature = "std")]
+/// Returns the data in the VM's return buffer.
+pub fn returndata_acquire() -> Vec<u8> {
+    let length = returndata_size();
+
+    let mut ret: Vec<u8> = unsafe_alloc_buffer(length);
+    unsafe_returndata_copy(0, length, &mut ret);
+    ret
+}
+
+/// Returns the segment of return buffer data beginning at `from` and continuing for `length` bytes.
+pub fn returndata_copy(from: usize, length: usize, ret: &mut [u8]) -> Result<(), Error> {
+    let size = returndata_size();
+
+    if (size < from) || ((size - from) < length) || (ret.len() < length) {
+        Err(Error::OutOfBoundsCopy)
+    } else {
+        unsafe_returndata_copy(from, length, ret);
+        Ok(())
+    }
+}
+
+/// Returns the length of the data in the VM's return buffer.
+pub fn returndata_size() -> usize {
+    unsafe { native::ethereum_getReturnDataSize() as usize }
+}
+
+/// Halts execution, reverts all changes to the state and consumes all gas.
+pub fn abort() -> ! {
+    // TODO: use assembly block with `unreachable`
+    panic!()
+}
+
+/// Halts execution and reverts all changes to the state.
+pub fn revert() -> ! {
+    unsafe {
+        native::ethereum_revert(0 as *const u32, 0 as u32);
+    }
+}
+
+/// Fills the return buffer with the given data and halts execution, reverting all state changes.
+pub fn revert_data(data: &[u8]) -> ! {
+    unsafe {
+        native::ethereum_revert(data.as_ptr() as *const u32, data.len() as u32);
+    }
+}
+
+/// Ends execution, signalling success.
+pub fn finish() -> ! {
+    unsafe {
+        native::ethereum_finish(0 as *const u32, 0 as u32);
+    }
+}
+
+/// Fills the return buffer with the given data and halts execution, signalling success.
+pub fn finish_data(data: &[u8]) -> ! {
+    unsafe {
+        native::ethereum_finish(data.as_ptr() as *const u32, data.len() as u32);
+    }
+}
+
+/// Accesses the storage data at the specified key.
+pub fn storage_load(key: &StorageKey) -> StorageValue {
+    let mut ret = StorageValue::default();
+
+    unsafe {
+        native::ethereum_storageLoad(
+            key.bytes.as_ptr() as *const u32,
+            ret.bytes.as_mut_ptr() as *const u32,
+        );
+    }
+
+    ret
+}
+
+/// Sets the storage data at the specified key.
+pub fn storage_store(key: &StorageKey, value: &StorageValue) {
+    unsafe {
+        native::ethereum_storageStore(
+            key.bytes.as_ptr() as *const u32,
+            value.bytes.as_ptr() as *const u32,
+        );
+    }
+}
+
+/// Self-destructs the running contract, sending all its ether to a specified beneficiary address.
+pub fn selfdestruct(address: &Address) -> ! {
+    unsafe {
+        native::ethereum_selfDestruct(address.bytes.as_ptr() as *const u32);
+    }
+}
+
+/*
+
+// add by echo : 扩展存储，以支持超过 32byte 的 key/value >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
+extern "C" {
+    pub fn ethereum_storageStore2(
+        keyOffset: *const u32, keyLength: u32,
+        valueOffset: *const u32, valueLength: u32,
+    );
+    pub fn ethereum_storageLoad2(
+        keyOffset: *const u32, keyLength: u32,
+        resultOffset: *const u32, resultType: u32,
+    );
+}
+
+// PUT Key->Val
+//pub fn storage_store2(key: &[u8], keyLen: u32, value: &[u8], valueLen: u32) {
+pub fn storage_store2(key: &[u8], value: &[u8]) {
+    let key_len = key.len();
+    let value_len = value.len();
+    unsafe {
+        ethereum_storageStore2(
+            key.as_ptr() as *const u32,
+            key_len as u32,
+            value.as_ptr() as *const u32,
+            value_len as u32,
+        );
+    }
+}
+
+pub fn storage_load2(key: &[u8]) -> Vec<u8> {
+    let key_len = key.len();
+    let mut val_len: [u8; 32] = [0; 32];
+    unsafe {
+        ethereum_storageLoad2(
+            key.as_ptr() as *const u32,
+            key_len as u32,
+            val_len.as_mut_ptr() as *const u32,
+            1,
+        );
+    }
+    //TODO 执行完上面的请求，好像有一个阻塞
+
+    let vl = metavmutils::bytes_to_uint(&val_len[..]);
+    let mut v: Vec<u8> = vec![0; vl];
+    unsafe {
+        ethereum_storageLoad2(
+            key.as_ptr() as *const u32,
+            key_len as u32,
+            v.as_mut_slice().as_mut_ptr() as *const u32,
+            2,
+        );
+    }
+    v
+}
+
+pub mod metavmutils {
+    pub fn bytes_to_uint(n: &[u8]) -> usize {
+        let size = n.len();
+        let mut r: usize = 0;
+        for i in 0..size {
+            let x = n[i] as usize;
+            if x > 0 {
+                let m = (size - 1 - i) * 8;
+                r = r + (x << m);
+            }
+        }
+        r
+    }
+
+    pub fn u32_to_bytes(i: u32) -> Vec<u8> {
+        let mut r: Vec<u8> = Vec::new();
+        r.insert(0, (i >> 24) as u8);
+        r.insert(1, (i >> 16) as u8);
+        r.insert(2, (i >> 8) as u8);
+        r.insert(3, i as u8);
+        r
+    }
+
+    pub fn u32_to_bytes32(i: u32) -> [u8; 32] {
+        let new_b: Vec<u8> = u32_to_bytes(i);
+        let mut val: [u8; 32] = [0; 32];
+        val[32 - 4] = new_b[0];
+        val[32 - 3] = new_b[1];
+        val[32 - 2] = new_b[2];
+        val[32 - 1] = new_b[3];
+        val
+    }
+}
+
+// add by echo : 扩展存储，以支持超过 32byte 的 key/value <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
+
+*/

src/metavm.rs

+// add by echo : 扩展存储，以支持超过 32byte 的 key/value >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
+extern "C" {
+    pub fn ethereum_storageStore2(
+        keyOffset: *const u32, keyLength: u32,
+        valueOffset: *const u32, valueLength: u32,
+    );
+    pub fn ethereum_storageLoad2(
+        keyOffset: *const u32, keyLength: u32,
+        resultOffset: *const u32, resultType: u32,
+    );
+}
+
+// PUT Key->Val
+//pub fn storage_store2(key: &[u8], keyLen: u32, value: &[u8], valueLen: u32) {
+pub fn storage_store(key: &[u8], value: &[u8]) {
+    let key_len = key.len();
+    let value_len = value.len();
+    unsafe {
+        ethereum_storageStore2(
+            key.as_ptr() as *const u32,
+            key_len as u32,
+            value.as_ptr() as *const u32,
+            value_len as u32,
+        );
+    }
+}
+
+pub fn storage_load(key: &[u8]) -> Vec<u8> {
+    let key_len = key.len();
+    let mut val_len: [u8; 32] = [0; 32];
+    unsafe {
+        ethereum_storageLoad2(
+            key.as_ptr() as *const u32,
+            key_len as u32,
+            val_len.as_mut_ptr() as *const u32,
+            1,
+        );
+    }
+    let vl = utils::bytes_to_uint(&val_len[..]);
+    let mut v: Vec<u8> = vec![0; vl];
+    unsafe {
+        ethereum_storageLoad2(
+            key.as_ptr() as *const u32,
+            key_len as u32,
+            v.as_mut_slice().as_mut_ptr() as *const u32,
+            2,
+        );
+    }
+    v
+}
+
+pub mod utils {
+    pub fn bytes_to_uint(n: &[u8]) -> usize {
+        let size = n.len();
+        let mut r: usize = 0;
+        for i in 0..size {
+            let x = n[i] as usize;
+            if x > 0 {
+                let m = (size - 1 - i) * 8;
+                r = r + (x << m);
+            }
+        }
+        r
+    }
+
+    pub fn u32_to_bytes(i: u32) -> Vec<u8> {
+        let mut r: Vec<u8> = Vec::new();
+        r.insert(0, (i >> 24) as u8);
+        r.insert(1, (i >> 16) as u8);
+        r.insert(2, (i >> 8) as u8);
+        r.insert(3, i as u8);
+        r
+    }
+
+    pub fn u32_to_bytes32(i: u32) -> [u8; 32] {
+        let new_b: Vec<u8> = u32_to_bytes(i);
+        let mut val: [u8; 32] = [0; 32];
+        val[32 - 4] = new_b[0];
+        val[32 - 3] = new_b[1];
+        val[32 - 2] = new_b[2];
+        val[32 - 1] = new_b[3];
+        val
+    }
+}
+// add by echo : 扩展存储，以支持超过 32byte 的 key/value <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<

src/native.rs

+//! The low-level bindings for the Ethereum Environment Interface (EEI). There is a safe set of wrappers for these functions, so use
+//! those unless you are certain you know what you're doing.
+
+extern "C" {
+    pub fn ethereum_useGas(amount: u64);
+    pub fn ethereum_getGasLeft() -> u64;
+    pub fn ethereum_getAddress(resultOffset: *const u32);
+    pub fn ethereum_getExternalBalance(addressOffset: *const u32, resultOffset: *const u32);
+    pub fn ethereum_getBlockCoinbase(resultOffset: *const u32);
+    pub fn ethereum_getBlockDifficulty(resultOffset: *const u32);
+    pub fn ethereum_getBlockGasLimit() -> u64;
+    pub fn ethereum_getBlockHash(number: u64, resultOffset: *const u32) -> u32;
+    pub fn ethereum_getBlockNumber() -> u64;
+    pub fn ethereum_getBlockTimestamp() -> u64;
+    pub fn ethereum_getTxGasPrice(valueOffset: *const u32);
+    pub fn ethereum_getTxOrigin(resultOffset: *const u32);
+    pub fn ethereum_log(
+        dataOffset: *const u32,
+        length: u32,
+        numberOfTopics: u32,
+        topic1: *const u32,
+        topic2: *const u32,
+        topic3: *const u32,
+        topic4: *const u32,
+    );
+    pub fn ethereum_call(
+        gas: u64,
+        addressOffset: *const u32,
+        valueOffset: *const u32,
+        dataOffset: *const u32,
+        dataLength: u32,
+    ) -> u32;
+    pub fn ethereum_callCode(
+        gas: u64,
+        addressOffset: *const u32,
+        valueOffset: *const u32,
+        dataOffset: *const u32,
+        dataLength: u32,
+    ) -> u32;
+    pub fn ethereum_callDelegate(
+        gas: u64,
+        addressOffset: *const u32,
+        dataOffset: *const u32,
+        dataLength: u32,
+    ) -> u32;
+    pub fn ethereum_callStatic(
+        gas: u64,
+        addressOffset: *const u32,
+        dataOffset: *const u32,
+        dataLength: u32,
+    ) -> u32;
+    pub fn ethereum_create(
+        valueOffset: *const u32,
+        dataOffset: *const u32,
+        dataLength: u32,
+        resultOffset: *const u32,
+    ) -> u32;
+    pub fn ethereum_returnDataCopy(resultOffset: *const u32, dataOffset: u32, length: u32);
+    pub fn ethereum_getReturnDataSize() -> u32;
+    pub fn ethereum_finish(dataOffset: *const u32, length: u32) -> !;
+    pub fn ethereum_revert(dataOffset: *const u32, length: u32) -> !;
+    pub fn ethereum_callDataCopy(resultOffset: *const u32, dataOffset: u32, length: u32);
+    pub fn ethereum_getCallDataSize() -> u32;
+    pub fn ethereum_getCaller(resultOffset: *const u32);
+    pub fn ethereum_getCallValue(resultOffset: *const u32);
+    pub fn ethereum_codeCopy(resultOffset: *const u32, codeOffset: u32, length: u32);
+    pub fn ethereum_getCodeSize() -> u32;
+    pub fn ethereum_externalCodeCopy(
+        addressOffset: *const u32,
+        resultOffset: *const u32,
+        codeOffset: u32,
+        length: u32,
+    );
+    pub fn ethereum_getExternalCodeSize(addressOfset: *const u32) -> u32;
+    pub fn ethereum_storageLoad(keyOffset: *const u32, resultOffset: *const u32);
+    pub fn ethereum_storageStore(keyOffset: *const u32, valueOffset: *const u32);
+    pub fn ethereum_selfDestruct(addressOffset: *const u32) -> !;
+}

src/types.rs

+//! High-level types commonly used in Ethereum contracts.
+
+/// A little-endian unsigned 128-bit integer.
+#[derive(Default, Copy, Clone, Debug, PartialEq, Eq)]
+pub struct Uint128 {
+    pub bytes: [u8; 16],
+}
+
+/// A little-endian unsigned 256-bit integer.
+#[derive(Default, Copy, Clone, Debug, PartialEq, Eq)]
+pub struct Uint256 {
+    pub bytes: [u8; 32],
+}
+
+/// An array of 160 bits.
+#[derive(Default, Copy, Clone, Debug, PartialEq, Eq)]
+pub struct Bytes20 {
+    pub bytes: [u8; 20],
+}
+
+/// An array of 256 bits.
+#[derive(Default, Copy, Clone, Debug, PartialEq, Eq)]
+pub struct Bytes32 {
+    pub bytes: [u8; 32],
+}
+
+/// Type definition representing a value in wei.
+pub type EtherValue = Uint128;
+
+/// Type definition representing an address.
+pub type Address = Bytes20;
+
+/// Type definition representing a storage key.
+pub type StorageKey = Bytes32;
+
+/// Type definition representing a storage value.
+pub type StorageValue = Bytes32;
+
+/// Type definition representing a log topic.
+pub type LogTopic = Bytes32;
+
+/// Type definition representing a Keccak-256 or SHA-256 hash.
+pub type Hash = Bytes32;
+
+/// Type definition representing a block's difficulty.
+pub type Difficulty = Uint256;
+
+macro_rules! from_primitive_impl {
+    ($f:ident, $size:expr, $to:ident) => {
+        impl From<[$f; $size]> for $to {
+            fn from(a: [$f; $size]) -> Self {
+                $to { bytes: a }
+            }
+        }
+    };
+}
+
+macro_rules! from_primitive_ref_impl {
+    ($f:ident, $size:expr, $to:ident) => {
+        impl From<&[$f; $size]> for $to {
+            fn from(a: &[$f; $size]) -> Self {
+                $to { bytes: a.clone() }
+            }
+        }
+    };
+}
+
+macro_rules! from_type_for_primitive_impl {
+    ($f:ident, $size:expr, $to:ident) => {
+        impl From<$f> for [$to; $size] {
+            fn from(a: $f) -> Self {
+                a.bytes
+            }
+        }
+    };
+}
+
+from_primitive_impl!(u8, 16, Uint128);
+from_primitive_impl!(u8, 32, Uint256);
+from_primitive_impl!(u8, 20, Bytes20);
+from_primitive_impl!(u8, 32, Bytes32);
+
+from_primitive_ref_impl!(u8, 16, Uint128);
+from_primitive_ref_impl!(u8, 32, Uint256);
+from_primitive_ref_impl!(u8, 20, Bytes20);
+from_primitive_ref_impl!(u8, 32, Bytes32);
+
+from_type_for_primitive_impl!(Uint128, 16, u8);
+from_type_for_primitive_impl!(Uint256, 32, u8);
+from_type_for_primitive_impl!(Bytes20, 20, u8);
+from_type_for_primitive_impl!(Bytes32, 32, u8);
+
+#[cfg(test)]
+mod tests {
+    use super::{Bytes20, Bytes32, Uint128, Uint256};
+
+    macro_rules! test_conversions {
+        ($type: ident, $size: expr, $test_name: ident) => {
+            #[test]
+            fn $test_name() {
+                let raw = [1; $size];
+
+                let uint = $type::from(raw);
+                assert_eq!(uint.bytes[$size - 1], 1);
+                let uint = $type::from(&raw);
+                assert_eq!(uint.bytes[$size - 1], 1);
+
+                let uint: $type = raw.into();
+                assert_eq!(uint.bytes[$size - 1], 1);
+                let uint: $type = (&raw).into();
+                assert_eq!(uint.bytes[$size - 1], 1);
+
+                let r: [u8; $size] = uint.into();
+                assert_eq!(r[$size - 1], 1);
+            }
+        };
+    }
+
+    test_conversions!(Uint128, 16, test_uint128);
+    test_conversions!(Uint256, 32, test_uint256);
+    test_conversions!(Bytes20, 20, test_bytes20);
+    test_conversions!(Bytes32, 32, test_bytes32);
+}

src/utils.rs

+//! General utility functions.
+
+/// Allocate an owned buffer using the global allocator.
+/// Only enabled with `std`.
+#[cfg(feature = "std")]
+pub fn unsafe_alloc_buffer(len: usize) -> Vec<u8> {
+    let mut ret: Vec<u8> = Vec::with_capacity(len);
+    unsafe {
+        ret.set_len(len);
+    }
+    ret
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn smoke() {
+        let ret = unsafe_alloc_buffer(42);
+        assert_eq!(ret.len(), 42);
+    }
+}