wasmer/lib/runtime-core/src/backend.rs
Lachlan Sneff 1886b3d3c1
Naive short circuiting implementation for user panics and results. (#167)
* Add panic and result catching

* exit process on panic and user runtime error

* Complete initial implementation
2019-02-08 13:08:03 -08:00

102 lines
2.9 KiB
Rust

use crate::{
backing::ImportBacking,
error::CompileResult,
error::RuntimeResult,
module::ModuleInner,
types::{FuncIndex, LocalFuncIndex, Value},
vm,
};
#[cfg(feature = "cache")]
use crate::{
cache::{Cache, Error as CacheError},
module::ModuleInfo,
sys::Memory,
};
use std::ptr::NonNull;
pub mod sys {
pub use crate::sys::*;
}
pub use crate::sig_registry::SigRegistry;
#[cfg_attr(feature = "cache", derive(Serialize, Deserialize))]
#[derive(Debug, Copy, Clone, PartialEq, Eq)]
pub enum Backend {
Cranelift,
}
/// This type cannot be constructed from
/// outside the runtime crate.
pub struct Token {
_private: (),
}
impl Token {
pub(crate) fn generate() -> Self {
Self { _private: () }
}
}
pub trait Compiler {
/// Compiles a `Module` from WebAssembly binary format.
/// The `CompileToken` parameter ensures that this can only
/// be called from inside the runtime.
fn compile(&self, wasm: &[u8], _: Token) -> CompileResult<ModuleInner>;
#[cfg(feature = "cache")]
unsafe fn from_cache(&self, cache: Cache, _: Token) -> Result<ModuleInner, CacheError>;
#[cfg(feature = "cache")]
fn compile_to_backend_cache_data(
&self,
wasm: &[u8],
_: Token,
) -> CompileResult<(Box<ModuleInfo>, Vec<u8>, Memory)>;
}
/// The functionality exposed by this trait is expected to be used
/// for calling functions exported by a webassembly module from
/// host code only.
pub trait ProtectedCaller: Send + Sync {
/// This calls the exported function designated by `local_func_index`.
/// Important to note, this supports calling imported functions that are
/// then exported.
///
/// It's invalid to attempt to call a local function that isn't exported and
/// the implementation is expected to check for that. The implementation
/// is also expected to check for correct parameter types and correct
/// parameter number.
///
/// The `returns` parameter is filled with dummy values when passed in and upon function
/// return, will be filled with the return values of the wasm function, as long as the
/// call completed successfully.
///
/// The existance of the Token parameter ensures that this can only be called from
/// within the runtime crate.
fn call(
&self,
module: &ModuleInner,
func_index: FuncIndex,
params: &[Value],
import_backing: &ImportBacking,
vmctx: *mut vm::Ctx,
_: Token,
) -> RuntimeResult<Vec<Value>>;
fn get_early_trapper(&self) -> Box<dyn UserTrapper>;
}
pub trait UserTrapper {
unsafe fn do_early_trap(&self, msg: String) -> !;
}
pub trait FuncResolver: Send + Sync {
/// This returns a pointer to the function designated by the `local_func_index`
/// parameter.
fn get(
&self,
module: &ModuleInner,
local_func_index: LocalFuncIndex,
) -> Option<NonNull<vm::Func>>;
}