1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79

// Copyright 2019 Joel Frank
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// 	https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

pub mod instructions;

use hex;
use std::collections::HashMap;
use std::io::Cursor;

use instructions::disassemble_next_byte;

pub use instructions::Instruction;

pub struct Disassembly {
    pub instructions: HashMap<usize, Instruction>,
}

impl Disassembly {
    pub fn from_hex_str(input: &str) -> Result<Self, hex::FromHexError> {
        let instructions = disassemble_hex_str(input)?;
        Ok(Self { instructions })
    }

    pub fn get(&self, addr: usize) -> Option<Instruction> {
        self.instructions.get(&addr).cloned()
    }
}

fn disassemble_hex_str(input: &str) -> Result<HashMap<usize, Instruction>, hex::FromHexError> {
    let input = if input[0..2] == *"0x" {
        &input[2..]
    } else {
        input
    };
    hex::decode(input).map(disassemble_bytes)
}

fn disassemble_bytes(bytes: Vec<u8>) -> HashMap<usize, Instruction> {
    let mut instructions = HashMap::new();
    let mut cursor = Cursor::new(bytes);
    while let Ok((offset, instruction)) = disassemble_next_byte(&mut cursor) {
        instructions.insert(offset, instruction);
    }

    instructions
}

#[cfg(test)]
mod tests {
    use super::*;
    use maplit::hashmap;

    #[test]
    fn simple_programm() {
        let program = "0x608040526002610100";
        let program_bytes = vec![0x60, 0x80, 0x40, 0x52, 0x60, 0x02, 0x61, 0x01, 0x00];
        let disas = hashmap! {
            0 => Instruction::Push(vec!(0x80)),
            2 => Instruction::Blockhash,
            3 => Instruction::MStore,
            4 => Instruction::Push(vec!(0x2)),
            6 => Instruction::Push(vec!(0x1, 0x00)),
        };

        assert_eq!(disassemble_hex_str(program).unwrap(), disas);
        assert_eq!(disassemble_bytes(program_bytes), disas);
    }
}