This commit is contained in:
elfein 2021-11-11 00:49:21 -08:00
parent 9f1b708ccf
commit e83cdc6ed9
2 changed files with 135 additions and 105 deletions

View file

@ -1,7 +1,7 @@
use wabt; use wabt;
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; mod wasm_sys;
@ -11,96 +11,96 @@ pub const KILL: usize = 0;
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 {
*SysCall::KILL => (&[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 {
SysCall::KILL => { SysCall::KILL => {
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" => SysCall::KILL, "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 {} has a bad signature", "Export {} not found",
field_name field_name
))); )))
} }
};
Ok(FuncInstance::alloc_host( if !self.check_signature(index, signature) {
Signature::new(&[ValueType::I32, ValueType::I32][..], Some(ValueType::I32)), return Err(Error::Instantiation(format!(
index, "Export {} has a bad signature",
)) 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!("../wasm/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()
); );
} }

View file

@ -1,36 +1,66 @@
#[repr(usize)] #[repr(usize)]
pub enum SysCall { pub enum SysCall {
KILL = 0, // Provide a PID KILL = 0, // Provide a PID
CONSOLE_RESET = 1, // Reset the console CONSOLE_RESET = 1, // Reset the console
CONSOLE_IN = 2, // Console Input CONSOLE_IN = 2, // Console Input
CONSOLE_OUT = 3, // Console output CONSOLE_OUT = 3, // Console output
CONSOLE_GET_TITLE = 4, // Get the console title CONSOLE_GET_TITLE = 4, // Get the console title
CONSOLE_SET_TITLE = 5, // Set the console title CONSOLE_SET_TITLE = 5, // Set the console title
//scheduler Related Syscals //scheduler Related Syscals
GET_PRIORITY = 10, // Get scheduler priority GET_PRIORITY = 10, // Get scheduler priority
SET_PRIORITY = 11, // Set scheduler priority SET_PRIORITY = 11, // Set scheduler priority
// //
GET_HOSTNAME = 12, GET_HOSTNAME = 12,
SET_HOSTNAME = 13, SET_HOSTNAME = 13,
//File Related syscalls //File Related syscalls
GET_CONFIG = 20, // Get config GET_CONFIG = 20, // Get config
SET_CONFIG = 21, // Set the config SET_CONFIG = 21, // Set the config
// //
MAKE_DIRECTORY = 22, // MAKE_DIRECTORY = 22, //
DELETE_DIRECTORY = 23, // DELETE_DIRECTORY = 23, //
RENAME_DIRECTORY = 24, // RENAME_DIRECTORY = 24, //
SET_DIRECTORY_ACCESS = 25, // SET_DIRECTORY_ACCESS = 25, //
// //
MAKE_FILE = 26, // MAKE_FILE = 26, //
DELETE_FILE = 27, // DELETE_FILE = 27, //
RENAME_FILE = 28, // RENAME_FILE = 28, //
SET_FILE_ACCESS = 29, // SET_FILE_ACCESS = 29, //
FILE_READ = 30, FILE_READ = 30,
FILE_WRITE = 31, FILE_WRITE = 31,
// Security Syscalls // Security Syscalls
ENCRYPT = 50, ENCRYPT = 50,
}
impl From<usize> for SysCall {
fn from(n: usize) -> Self {
match n {
0 => Self::KILL,
1 => Self::CONSOLE_RESET,
2 => Self::CONSOLE_IN,
3 => Self::CONSOLE_OUT,
4 => Self::CONSOLE_GET_TITLE,
5 => Self::CONSOLE_SET_TITLE,
10 => Self::GET_PRIORITY,
11 => Self::SET_PRIORITY,
12 => Self::GET_HOSTNAME,
13 => Self::SET_HOSTNAME,
20 => Self::GET_CONFIG,
21 => Self::SET_CONFIG,
22 => Self::MAKE_DIRECTORY,
23 => Self::DELETE_DIRECTORY,
24 => Self::RENAME_DIRECTORY,
25 => Self::SET_DIRECTORY_ACCESS,
26 => Self::MAKE_FILE,
27 => Self::DELETE_FILE,
28 => Self::RENAME_FILE,
29 => Self::SET_FILE_ACCESS,
30 => Self::FILE_READ,
31 => Self::FILE_WRITE,
50 => Self::ENCRYPT,
}
}
} }