Merge pull request #51 from gavofyork/jit_improvements

jit ffi improvements [please review]

rust-evmjit/Cargo.toml

@@ -5,3 +5,4 @@ authors = ["debris <marek.kotewicz@gmail.com>"]
 
 [dependencies]
 libc = "0.2.2"
+tiny-keccak = "1.0"

rust-evmjit/src/lib.rs

@@ -1,16 +1,190 @@
-//! Bare rust wrapper around evmjit
+//! Bare rust wrapper around evmjit.
 //! 
 //! Requires latest version of Ethereum EVM JIT. https://github.com/debris/evmjit
+//! 
+//! ```
+//! extern crate evmjit;
+//! use evmjit::*;
+//! 
+//! fn main() {
+//! 	let mut context = ContextHandle::new(RuntimeDataHandle::new(), EnvHandle::empty());
+//! 	assert_eq!(context.exec(), ReturnCode::Stop);
+//! }
+//!
+//! ```
 
 extern crate libc;
-use std::ptr;
+extern crate tiny_keccak;
+
+use std::ops::{Deref, DerefMut};
+use self::ffi::*;
+
+pub use self::ffi::JitReturnCode as ReturnCode;
+
+/// Component oriented safe handle to `JitRuntimeData`.
+pub struct RuntimeDataHandle {
+	runtime_data: *mut JitRuntimeData
+}
+
+impl RuntimeDataHandle {
+	/// Creates new handle.
+	pub fn new() -> Self {
+		RuntimeDataHandle {
+			runtime_data: unsafe { evmjit_create_runtime_data() }
+		}
+	}
+
+	/// Returns immutable reference to runtime data.
+	pub fn runtime_data(&self) -> &JitRuntimeData {
+		unsafe { &*self.runtime_data }
+	}
+
+	/// Returns mutable reference to runtime data.
+	pub fn mut_runtime_data(&mut self) -> &mut JitRuntimeData {
+		unsafe { &mut *self.runtime_data }
+	}
+}
+
+impl Drop for RuntimeDataHandle {
+	fn drop(&mut self) {
+		unsafe { evmjit_destroy_runtime_data(self.runtime_data) }
+	}
+}
+
+/// Safe handle for jit context.
+pub struct ContextHandle {
+	context: *mut JitContext,
+	_data_handle: RuntimeDataHandle
+}
+
+impl ContextHandle {
+	/// Creates new context handle.
+	pub fn new(mut data_handle: RuntimeDataHandle, mut env: EnvHandle) -> Self {
+		let context = unsafe { evmjit_create_context(data_handle.mut_runtime_data(), &mut env) };
+		ContextHandle {
+			context: context,
+			_data_handle: data_handle
+		}
+	}
+
+	/// Executes context.
+	pub fn exec(&mut self) -> JitReturnCode {
+		unsafe { evmjit_exec(self.context) }
+	}
+}
+
+impl Drop for ContextHandle {
+	fn drop(&mut self) {
+		unsafe { evmjit_destroy_context(self.context); }
+	}
+}
+
+/// Component oriented wrapper around jit env c interface.
+pub trait Env {
+	fn sload(&self, index: *const JitI256, out_value: *mut JitI256);
+	fn sstore(&mut self, index: *const JitI256, value: *const JitI256);
+	fn balance(&self, address: *const JitI256, out_value: *mut JitI256);
+	fn blockhash(&self, number: *const JitI256, out_hash: *mut JitI256);
+
+	fn create(&mut self,
+			  io_gas: *mut u64,
+			  endowment: *const JitI256,
+			  init_beg: *const u8,
+			  init_size: *const u64,
+			  address: *mut JitI256);
+
+	fn call(&mut self,
+				io_gas: *mut u64,
+				call_gas: *const u64,
+				receive_address: *const JitI256,
+				value: *const JitI256,
+				in_beg: *const u8,
+				in_size: *const u64,
+				out_beg: *mut u8,
+				out_size: *mut u64,
+				code_address: JitI256) -> bool;
+
+	fn log(&mut self,
+		   beg: *const u8,
+		   size: *const u64,
+		   topic1: *const JitI256,
+		   topic2: *const JitI256,
+		   topic3: *const JitI256,
+		   topic4: *const JitI256);
+
+	fn extcode(&self, address: *const JitI256, size: *mut u64) -> *const u8;
+}
+
+/// C abi compatible wrapper for jit env implementers.
+pub struct EnvHandle {
+	env_impl: Option<Box<Env>>
+}
+
+impl EnvHandle {
+	/// Creates new environment wrapper for given implementation
+	pub fn new<T>(env_impl: T) -> Self where T: Env + 'static {
+		EnvHandle { env_impl: Some(Box::new(env_impl)) }
+	}
+
+	/// Creates empty environment.
+	/// It can be used to for any operations.
+	pub fn empty() -> Self {
+		EnvHandle { env_impl: None }
+	}
+}
+
+impl Deref for EnvHandle {
+	type Target = Box<Env>;
+
+	fn deref(&self) -> &Self::Target {
+		match self.env_impl {
+			Some(ref env) => env,
+			None => { panic!(); }
+		}
+	}
+}
+
+impl DerefMut for EnvHandle {
+	fn deref_mut(&mut self) -> &mut Self::Target {
+		match self.env_impl {
+			Some(ref mut env) => env,
+			None => { panic!(); }
+		}
+	}
+}
+
+/// ffi functions
+pub mod ffi {
+	use std::slice;
+	use libc;
+	use tiny_keccak::Keccak;
+	use super::*;
+
+	/// Jit context struct declaration.
+	pub enum JitContext {}
 
 	#[repr(C)]
+	#[derive(Debug, Eq, PartialEq)]
+	/// Jit context execution return code.
+	pub enum JitReturnCode {
+		Stop = 0,
+		Return = 1,
+		Suicide = 2,
+
+		OutOfGas = -1,
+
+		LLVMError = -101,
+		UnexpectedError = -111
+	}
+
+	#[repr(C)]
+	/// Signed 256 bit integer.
 	pub struct JitI256 {
 		pub words: [u64; 4]
 	}
 
 	#[repr(C)]
+	/// Jit runtime data.
 	pub struct JitRuntimeData {
 		pub gas: i64,
 		pub gas_price: i64,
@@ -30,38 +204,107 @@ pub struct JitRuntimeData {
 		pub code_hash: JitI256
 	}
 
-#[repr(C)]
-#[derive(Debug, Eq, PartialEq)]
-pub enum JitReturnCode {
-	Stop = 0,
-	Return = 1,
-	Suicide = 2,
-
-	OutOfGas = -1,
-
-	LLVMError = -101,
-	UnexpectedError = -111
+	#[no_mangle]
+	pub unsafe extern fn env_sload(env: *const EnvHandle, index: *const JitI256, out_value: *mut JitI256) {
+		let env = &*env;
+		env.sload(index, out_value);
+	}
+
+	#[no_mangle]
+	pub unsafe extern fn env_sstore(env: *mut EnvHandle, index: *const JitI256, value: *const JitI256) {
+		let env = &mut *env;
+		env.sstore(index, value);
+	}
+
+	#[no_mangle]
+	pub unsafe extern fn env_balance(env: *const EnvHandle, address: *const JitI256, out_value: *mut JitI256) {
+		let env = &*env;
+		env.balance(address, out_value);
+	}
+
+	#[no_mangle]
+	pub unsafe extern fn env_blockhash(env: *const EnvHandle, number: *const JitI256, out_hash: *mut JitI256) {
+		let env = &*env;
+		env.blockhash(number, out_hash);
+	}
+
+	#[no_mangle]
+	pub unsafe extern fn env_create(env: *mut EnvHandle, 
+							 io_gas: *mut u64, 
+							 endowment: *const JitI256, 
+							 init_beg: *const u8, 
+							 init_size: *const u64, 
+							 address: *mut JitI256) {
+		let env = &mut *env;
+		env.create(io_gas, endowment, init_beg, init_size, address);
+	}
+
+	#[no_mangle]
+	pub unsafe extern fn env_call(env: *mut EnvHandle, 
+						   io_gas: *mut u64,
+						   call_gas: *const u64,
+						   receive_address: *const JitI256,
+						   value: *const JitI256,
+						   in_beg: *const u8,
+						   in_size: *const u64,
+						   out_beg: *mut u8,
+						   out_size: *mut u64,
+						   code_address: JitI256) -> bool {
+		let env = &mut *env;
+		env.call(io_gas, call_gas, receive_address, value, in_beg, in_size, out_beg, out_size, code_address)
+	}
+
+	#[no_mangle]
+	pub unsafe extern fn env_sha3(begin: *const u8, size: *const u64, out_hash: *mut JitI256) {
+		let out_hash = &mut *out_hash;
+		let input = slice::from_raw_parts(begin, *size as usize);
+		let outlen = out_hash.words.len() * 8;
+		let output = slice::from_raw_parts_mut(out_hash.words.as_mut_ptr() as *mut u8, outlen);
+		let mut sha3 = Keccak::new_sha3_256();
+		sha3.update(input);	
+		sha3.finalize(output);
+	}
+
+	#[no_mangle]
+	pub unsafe extern fn env_extcode(env: *const EnvHandle, address: *const JitI256, size: *mut u64) -> *const u8 {
+		let env = &*env;
+		env.extcode(address, size)
+	}
+
+	#[no_mangle]
+	pub unsafe extern fn env_log(env: *mut EnvHandle,
+						  beg: *const u8,
+						  size: *const u64,
+						  topic1: *const JitI256,
+						  topic2: *const JitI256,
+						  topic3: *const JitI256,
+						  topic4: *const JitI256) {
+		let env = &mut *env;
+		env.log(beg, size, topic1, topic2, topic3, topic4);
 	}
 
-pub enum JitContext {}
 
 	#[link(name="evmjit")]
 	extern "C" {
 		pub fn evmjit_create_runtime_data() -> *mut JitRuntimeData;
 		pub fn evmjit_destroy_runtime_data(data: *mut JitRuntimeData);
-
-	pub fn evmjit_create_context(data: *mut JitRuntimeData, env: u8) -> *mut JitContext;
 		pub fn evmjit_destroy_context(context: *mut JitContext);
-
 		pub fn evmjit_exec(context: *mut JitContext) -> JitReturnCode;
+	}
 
+	#[link(name="evmjit")]
+	// EnvHandle does not have to by a C type
+	#[allow(improper_ctypes)]
+	extern "C" {
+		pub fn evmjit_create_context(data: *mut JitRuntimeData, env: *mut EnvHandle) -> *mut JitContext;
+	}
 }
 
 #[test]
-fn it_works() {
+fn ffi_test() {
 	unsafe {
 		let data = evmjit_create_runtime_data();
-		let context = evmjit_create_context(data, 0);
+		let context = evmjit_create_context(data, &mut EnvHandle::empty());
 
 		let code = evmjit_exec(context);
 		assert_eq!(code, JitReturnCode::Stop);
@@ -71,3 +314,8 @@ fn it_works() {
 	}
 }
 
+#[test]
+fn handle_test() {
+	let mut context = ContextHandle::new(RuntimeDataHandle::new(), EnvHandle::empty());
+	assert_eq!(context.exec(), ReturnCode::Stop);
+}