1234#![allow(dead_code)]56#[cfg(not(feature = "std"))]7use alloc::{8 string::{String, ToString},9 vec::Vec,10};11use primitive_types::{H160, U256};1213use crate::types::string;1415const ABI_ALIGNMENT: usize = 32;1617pub type Result<T> = core::result::Result<T, &'static str>;1819#[derive(Clone)]20pub struct AbiReader<'i> {21 buf: &'i [u8],22 offset: usize,23}24impl<'i> AbiReader<'i> {25 pub fn new(buf: &'i [u8]) -> Self {26 Self { buf, offset: 0 }27 }28 pub fn new_call(buf: &'i [u8]) -> Result<(u32, Self)> {29 if buf.len() < 4 {30 return Err("missing method id");31 }32 let mut method_id = [0; 4];33 method_id.copy_from_slice(&buf[0..4]);3435 Ok((u32::from_be_bytes(method_id), Self { buf, offset: 4 }))36 }3738 fn read_padleft<const S: usize>(&mut self) -> Result<[u8; S]> {39 if self.buf.len() - self.offset < 32 {40 return Err("missing padding");41 }42 let mut block = [0; S];43 44 if !self.buf[self.offset..self.offset + ABI_ALIGNMENT - S]45 .iter()46 .all(|&v| v == 0)47 {48 return Err("non zero padding (wrong types?)");49 }50 block.copy_from_slice(51 &self.buf[self.offset + ABI_ALIGNMENT - S..self.offset + ABI_ALIGNMENT],52 );53 self.offset += ABI_ALIGNMENT;54 Ok(block)55 }5657 pub fn address(&mut self) -> Result<H160> {58 Ok(H160(self.read_padleft()?))59 }6061 pub fn bool(&mut self) -> Result<bool> {62 let data: [u8; 1] = self.read_padleft()?;63 match data[0] {64 0 => Ok(false),65 1 => Ok(true),66 _ => Err("wrong bool value"),67 }68 }6970 pub fn bytes4(&mut self) -> Result<[u8; 4]> {71 self.read_padleft()72 }7374 pub fn bytes(&mut self) -> Result<Vec<u8>> {75 let mut subresult = self.subresult()?;76 let length = subresult.read_usize()?;77 if subresult.buf.len() <= subresult.offset + length {78 return Err("bytes out of bounds");79 }80 Ok(subresult.buf[subresult.offset..subresult.offset + length].into())81 }8283 pub fn uint32(&mut self) -> Result<u32> {84 Ok(u32::from_be_bytes(self.read_padleft()?))85 }8687 pub fn uint128(&mut self) -> Result<u128> {88 Ok(u128::from_be_bytes(self.read_padleft()?))89 }9091 pub fn uint256(&mut self) -> Result<U256> {92 let buf: [u8; 32] = self.read_padleft()?;93 Ok(U256::from_big_endian(&buf))94 }9596 pub fn uint64(&mut self) -> Result<u64> {97 Ok(u64::from_be_bytes(self.read_padleft()?))98 }99100 pub fn read_usize(&mut self) -> Result<usize> {101 Ok(usize::from_be_bytes(self.read_padleft()?))102 }103104 fn subresult(&mut self) -> Result<AbiReader<'i>> {105 let offset = self.read_usize()?;106 Ok(AbiReader {107 buf: &self.buf,108 offset: offset + self.offset,109 })110 }111112 pub fn is_finished(&self) -> bool {113 self.buf.len() == self.offset114 }115}116117#[derive(Default)]118pub struct AbiWriter {119 static_part: Vec<u8>,120 dynamic_part: Vec<(usize, AbiWriter)>,121}122impl AbiWriter {123 pub fn new() -> Self {124 Self::default()125 }126 pub fn new_call(method_id: u32) -> Self {127 let mut val = Self::new();128 val.static_part.extend(&method_id.to_be_bytes());129 val130 }131132 fn write_padleft(&mut self, block: &[u8]) {133 assert!(block.len() <= ABI_ALIGNMENT);134 self.static_part135 .extend(&[0; ABI_ALIGNMENT][0..ABI_ALIGNMENT - block.len()]);136 self.static_part.extend(block);137 }138139 fn write_padright(&mut self, bytes: &[u8]) {140 assert!(bytes.len() <= ABI_ALIGNMENT);141 self.static_part.extend(bytes);142 self.static_part143 .extend(&[0; ABI_ALIGNMENT][0..ABI_ALIGNMENT - bytes.len()]);144 }145146 pub fn address(&mut self, address: &H160) {147 self.write_padleft(&address.0)148 }149150 pub fn bool(&mut self, value: &bool) {151 self.write_padleft(&[if *value { 1 } else { 0 }])152 }153154 pub fn uint8(&mut self, value: &u8) {155 self.write_padleft(&[*value])156 }157158 pub fn uint32(&mut self, value: &u32) {159 self.write_padleft(&u32::to_be_bytes(*value))160 }161162 pub fn uint128(&mut self, value: &u128) {163 self.write_padleft(&u128::to_be_bytes(*value))164 }165166 167 168 pub fn uint256(&mut self, value: &U256) {169 let mut out = [0; 32];170 value.to_big_endian(&mut out);171 self.write_padleft(&out)172 }173174 pub fn write_usize(&mut self, value: &usize) {175 self.write_padleft(&usize::to_be_bytes(*value))176 }177178 pub fn write_subresult(&mut self, result: Self) {179 self.dynamic_part.push((self.static_part.len(), result));180 181 self.write_padleft(&[]);182 }183184 pub fn memory(&mut self, value: &[u8]) {185 let mut sub = Self::new();186 sub.write_usize(&value.len());187 for chunk in value.chunks(ABI_ALIGNMENT) {188 sub.write_padright(chunk);189 }190 self.write_subresult(sub);191 }192193 pub fn string(&mut self, value: &str) {194 self.memory(value.as_bytes())195 }196197 pub fn finish(mut self) -> Vec<u8> {198 for (static_offset, part) in self.dynamic_part {199 let part_offset = self.static_part.len();200201 let encoded_dynamic_offset = usize::to_be_bytes(part_offset - static_offset);202 self.static_part[static_offset + ABI_ALIGNMENT - encoded_dynamic_offset.len()203 ..static_offset + ABI_ALIGNMENT]204 .copy_from_slice(&encoded_dynamic_offset);205 self.static_part.extend(part.finish())206 }207 self.static_part208 }209}210211pub trait AbiRead<T> {212 fn abi_read(&mut self) -> Result<T>;213}214215macro_rules! impl_abi_readable {216 ($ty:ty, $method:ident) => {217 impl AbiRead<$ty> for AbiReader<'_> {218 fn abi_read(&mut self) -> Result<$ty> {219 self.$method()220 }221 }222 };223}224225impl_abi_readable!(u32, uint32);226impl_abi_readable!(u128, uint128);227impl_abi_readable!(U256, uint256);228impl_abi_readable!(H160, address);229impl_abi_readable!(Vec<u8>, bytes);230impl_abi_readable!(bool, bool);231232pub trait AbiWrite {233 fn abi_write(&self, writer: &mut AbiWriter);234}235236macro_rules! impl_abi_writeable {237 ($ty:ty, $method:ident) => {238 impl AbiWrite for $ty {239 fn abi_write(&self, writer: &mut AbiWriter) {240 writer.$method(&self)241 }242 }243 };244}245246impl_abi_writeable!(u8, uint8);247impl_abi_writeable!(u32, uint32);248impl_abi_writeable!(u128, uint128);249impl_abi_writeable!(U256, uint256);250impl_abi_writeable!(H160, address);251impl_abi_writeable!(bool, bool);252impl_abi_writeable!(&str, string);253impl AbiWrite for &string {254 fn abi_write(&self, writer: &mut AbiWriter) {255 writer.string(&self)256 }257}258259impl AbiWrite for () {260 fn abi_write(&self, _writer: &mut AbiWriter) {}261}262263264265#[derive(Debug)]266pub struct StringError(String);267268impl<E> From<E> for StringError269where270 E: ToString,271{272 fn from(e: E) -> Self {273 Self(e.to_string())274 }275}276277impl From<StringError> for AbiWriter {278 fn from(v: StringError) -> Self {279 let mut out = AbiWriter::new_call(crate::fn_selector!(Error(string)));280 out.string(&v.0);281 out282 }283}284285#[macro_export]286macro_rules! abi_decode {287 ($reader:expr, $($name:ident: $typ:ident),+ $(,)?) => {288 $(289 let $name = $reader.$typ()?;290 )+291 }292}293#[macro_export]294macro_rules! abi_encode {295 ($($typ:ident($value:expr)),* $(,)?) => {{296 #[allow(unused_mut)]297 let mut writer = ::evm_coder::abi::AbiWriter::new();298 $(299 writer.$typ($value);300 )*301 writer302 }};303 (call $val:expr; $($typ:ident($value:expr)),* $(,)?) => {{304 #[allow(unused_mut)]305 let mut writer = ::evm_coder::abi::AbiWriter::new_call($val);306 $(307 writer.$typ($value);308 )*309 writer310 }}311}