This commit is contained in:
Able 2021-11-11 18:41:16 -06:00
parent 04859555e9
commit 9f1b708ccf
4 changed files with 122 additions and 97 deletions

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@ -1,107 +1,106 @@
extern crate wabt; use wabt;
extern crate wasmi;
use wasmi::{ use wasmi::{
Error, Externals, FuncInstance, FuncRef, ImportsBuilder, ModuleImportResolver, ModuleInstance, Error, Externals, FuncInstance, FuncRef, ImportsBuilder, ModuleImportResolver, ModuleInstance,
RuntimeArgs, RuntimeValue, Signature, Trap, ValueType, RuntimeArgs, RuntimeValue, Signature, Trap, ValueType,
}; };
mod wasm_sys;
use wasm_sys::SysCall;
pub const KILL: usize = 0; pub const KILL: usize = 0;
pub const ADD_FUNC_INDEX: usize = 1;
struct HostFunctions; struct HostFunctions;
impl HostFunctions { impl HostFunctions {
fn check_signature(&self, index: usize, signature: &Signature) -> bool { fn check_signature(&self, index: usize, signature: &Signature) -> bool {
let (params, ret_ty): (&[ValueType], Option<ValueType>) = match index { let (params, ret_ty): (&[ValueType], Option<ValueType>) = match index {
ADD_FUNC_INDEX => (&[ValueType::I32, ValueType::I32], Some(ValueType::I32)), *SysCall::KILL => (&[ValueType::I32, ValueType::I32], Some(ValueType::I32)),
_ => return false, _ => return false,
}; };
signature.params() == params && signature.return_type() == ret_ty signature.params() == params && signature.return_type() == ret_ty
} }
} }
impl Externals for HostFunctions { impl Externals for HostFunctions {
fn invoke_index( fn invoke_index(
&mut self, &mut self,
index: usize, index: usize,
args: RuntimeArgs, args: RuntimeArgs,
) -> Result<Option<RuntimeValue>, Trap> { ) -> Result<Option<RuntimeValue>, Trap> {
match index { match index {
ADD_FUNC_INDEX => { SysCall::KILL => {
println!("you pe"); let a: u32 = args.nth_checked(0)?;
let a: u32 = args.nth_checked(0)?; let b: u32 = args.nth_checked(1)?;
let b: u32 = args.nth_checked(1)?; let result = a + b;
let result = a + b;
Ok(Some(RuntimeValue::I32(result as i32))) Ok(Some(RuntimeValue::I32(result as i32)))
} }
_ => panic!("Unimplemented function at {}", index), _ => panic!("Unimplemented function at {}", index),
} }
} }
} }
impl ModuleImportResolver for HostFunctions { impl ModuleImportResolver for HostFunctions {
fn resolve_func(&self, field_name: &str, signature: &Signature) -> Result<FuncRef, Error> { fn resolve_func(&self, field_name: &str, signature: &Signature) -> Result<FuncRef, Error> {
let index = match field_name { let index = match field_name {
"add" => ADD_FUNC_INDEX, "add" => SysCall::KILL,
_ => { _ => {
return Err(Error::Instantiation(format!(
"Export {} not found",
field_name
)))
}
};
if !self.check_signature(index, signature) {
return Err(Error::Instantiation(format!( return Err(Error::Instantiation(format!(
"Export {} not found", "Export {} has a bad signature",
field_name field_name
))) )));
} }
};
if !self.check_signature(index, signature) { Ok(FuncInstance::alloc_host(
return Err(Error::Instantiation(format!( Signature::new(&[ValueType::I32, ValueType::I32][..], Some(ValueType::I32)),
"Export {} has a bad signature", index,
field_name ))
))); }
}
Ok(FuncInstance::alloc_host(
Signature::new(&[ValueType::I32, ValueType::I32][..], Some(ValueType::I32)),
index,
))
}
} }
fn main() { fn main() {
// Parse WAT (WebAssembly Text format) into wasm bytecode. // Parse WAT (WebAssembly Text format) into wasm bytecode.
let wasm_binary = wabt::wat2wasm(include_str!("test.wat")); let wasm_binary = wabt::wat2wasm(include_str!("../wasm/test.wat"));
let wasm_binary = match wasm_binary { let wasm_binary = match wasm_binary {
Ok(abc) => abc, Ok(abc) => abc,
Err(abc) => { Err(abc) => {
println!("{}", abc); println!("{}", abc);
return; return;
} }
}; };
// .expect("failed to parse wat"); // .expect("failed to parse wat");
// Load wasm binary and prepare it for instantiation. // Load wasm binary and prepare it for instantiation.
let module = wasmi::Module::from_buffer(&wasm_binary).expect("failed to load wasm"); let module = wasmi::Module::from_buffer(&wasm_binary).expect("failed to load wasm");
let imports = ImportsBuilder::new().with_resolver("host", &HostFunctions); let imports = ImportsBuilder::new().with_resolver("host", &HostFunctions);
// Instantiate a module with empty imports and // Instantiate a module with empty imports and
// assert that there is no `start` function. // assert that there is no `start` function.
let instance = ModuleInstance::new(&module, &imports) let instance = ModuleInstance::new(&module, &imports)
.expect("failed to instantiate wasm module") .expect("failed to instantiate wasm module")
.assert_no_start(); .assert_no_start();
// Finally, invoke the exported function "test" with no parameters // Finally, invoke the exported function "test" with no parameters
// and empty external function executor. // and empty external function executor.
let result: i32 = instance let result: i32 = instance
.invoke_export("main", &[], &mut HostFunctions) .invoke_export("main", &[], &mut HostFunctions)
// .with_resolver(&mut HostFunctions) // .with_resolver(&mut HostFunctions)
.expect("failed to execute export") .expect("failed to execute export")
.unwrap() .unwrap()
.try_into() .try_into()
.unwrap(); .unwrap();
println!( println!(
"{:?}", "{:?}",
result // .unwrap() result // .unwrap()
); );
} }

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@ -1,16 +0,0 @@
(module
(import "host" "add" (func $add (param i32 i32)(result i32)))
(func (export "main") (result i32)
(call $add (i32.const 123) (i32.const 456))
(; i32.const 1337 ;)
)
)
(;;
(func $main (export "_start")
(; (call $print_greeting) ;)
return
)
;;)

36
src/wasm_sys.rs Normal file
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@ -0,0 +1,36 @@
#[repr(usize)]
pub enum SysCall {
KILL = 0, // Provide a PID
CONSOLE_RESET = 1, // Reset the console
CONSOLE_IN = 2, // Console Input
CONSOLE_OUT = 3, // Console output
CONSOLE_GET_TITLE = 4, // Get the console title
CONSOLE_SET_TITLE = 5, // Set the console title
//scheduler Related Syscals
GET_PRIORITY = 10, // Get scheduler priority
SET_PRIORITY = 11, // Set scheduler priority
//
GET_HOSTNAME = 12,
SET_HOSTNAME = 13,
//File Related syscalls
GET_CONFIG = 20, // Get config
SET_CONFIG = 21, // Set the config
//
MAKE_DIRECTORY = 22, //
DELETE_DIRECTORY = 23, //
RENAME_DIRECTORY = 24, //
SET_DIRECTORY_ACCESS = 25, //
//
MAKE_FILE = 26, //
DELETE_FILE = 27, //
RENAME_FILE = 28, //
SET_FILE_ACCESS = 29, //
FILE_READ = 30,
FILE_WRITE = 31,
// Security Syscalls
ENCRYPT = 50,
}

6
wasm/test.wat Normal file
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@ -0,0 +1,6 @@
(module
(import "host" "add" (func $add (param i32 i32)(result i32)))
(func (export "main") (result i32)
(call $add (i32.const 123) (i32.const 456))
)
)