#![deny(warnings)]
#![forbid(unsafe_code, unused_variables, unused_imports)]
#![cfg_attr(not(feature = "std"), no_std)]
extern crate alloc;
mod error;
mod eval;
mod external;
mod memory;
mod opcode;
mod stack;
mod utils;
mod valids;
pub use crate::error::{Capture, ExitError, ExitFatal, ExitReason, ExitRevert, ExitSucceed, Trap};
pub use crate::external::ExternalOperation;
pub use crate::memory::Memory;
pub use crate::opcode::Opcode;
pub use crate::stack::Stack;
pub use crate::valids::Valids;
use crate::eval::{eval, Control};
use alloc::rc::Rc;
use alloc::vec::Vec;
use core::ops::Range;
use primitive_types::U256;
pub struct Machine {
data: Rc<Vec<u8>>,
code: Rc<Vec<u8>>,
position: Result<usize, ExitReason>,
return_range: Range<U256>,
valids: Valids,
memory: Memory,
stack: Stack,
}
impl Machine {
pub fn stack(&self) -> &Stack {
&self.stack
}
pub fn stack_mut(&mut self) -> &mut Stack {
&mut self.stack
}
pub fn memory(&self) -> &Memory {
&self.memory
}
pub fn memory_mut(&mut self) -> &mut Memory {
&mut self.memory
}
pub fn position(&self) -> &Result<usize, ExitReason> {
&self.position
}
pub fn new(
code: Rc<Vec<u8>>,
data: Rc<Vec<u8>>,
stack_limit: usize,
memory_limit: usize,
) -> Self {
let valids = Valids::new(&code[..]);
Self {
data,
code,
position: Ok(0),
return_range: U256::zero()..U256::zero(),
valids,
memory: Memory::new(memory_limit),
stack: Stack::new(stack_limit),
}
}
pub fn exit(&mut self, reason: ExitReason) {
self.position = Err(reason);
}
pub fn inspect(&self) -> Option<(Opcode, &Stack)> {
let position = match self.position {
Ok(position) => position,
Err(_) => return None,
};
self.code.get(position).map(|v| (Opcode(*v), &self.stack))
}
pub fn return_value(&self) -> Vec<u8> {
if self.return_range.start > U256::from(usize::MAX) {
let mut ret = Vec::new();
ret.resize(
(self.return_range.end - self.return_range.start).as_usize(),
0,
);
ret
} else if self.return_range.end > U256::from(usize::MAX) {
let mut ret = self.memory.get(
self.return_range.start.as_usize(),
usize::MAX - self.return_range.start.as_usize(),
);
while ret.len() < (self.return_range.end - self.return_range.start).as_usize() {
ret.push(0);
}
ret
} else {
self.memory.get(
self.return_range.start.as_usize(),
(self.return_range.end - self.return_range.start).as_usize(),
)
}
}
pub fn run(&mut self) -> Capture<ExitReason, Trap> {
loop {
match self.step() {
Ok(()) => (),
Err(res) => return res,
}
}
}
#[inline]
pub fn step(&mut self) -> Result<(), Capture<ExitReason, Trap>> {
let position = *self
.position
.as_ref()
.map_err(|reason| Capture::Exit(reason.clone()))?;
match self.code.get(position).map(|v| Opcode(*v)) {
Some(opcode) => match eval(self, opcode, position) {
Control::Continue(p) => {
self.position = Ok(position + p);
Ok(())
}
Control::Exit(e) => {
self.position = Err(e.clone());
Err(Capture::Exit(e))
}
Control::Jump(p) => {
self.position = Ok(p);
Ok(())
}
Control::Trap(opcode) => {
#[cfg(feature = "force-debug")]
log::trace!(target: "evm", "OpCode Trap: {:?}", opcode);
self.position = Ok(position + 1);
Err(Capture::Trap(opcode))
}
},
None => {
self.position = Err(ExitSucceed::Stopped.into());
Err(Capture::Exit(ExitSucceed::Stopped.into()))
}
}
}
}