oden/oden-js/src/lib.rs

109 lines
3.6 KiB
Rust

use oden_js_sys as sys;
use std::ffi::{CString, NulError};
use thiserror::Error;
mod atom;
mod callback;
mod class;
mod context;
mod conversion;
pub mod module;
mod runtime;
mod value;
pub use atom::{Atom, AtomRef};
pub use class::{Class, ClassID};
pub use context::{Context, ContextRef, EvalFlags};
pub use conversion::*;
pub use runtime::Runtime;
pub use value::{Value, ValueRef, ValueType};
#[derive(Debug, Error)]
pub enum Error {
#[error("too many classes have been registered")]
TooManyClasses,
#[error("the specified value is not an instance of the class {0}")]
WrongClass(String),
#[error("input script contained an embedded NUL byte")]
UnexpectedNul,
#[error("the target context is from a different runtime")]
DifferentRuntime,
#[error("the specified value had the wrong type (expected {expected:?}, found {found:?})")]
InvalidType {
expected: ValueType,
found: ValueType,
},
#[error("argument count mismatch, expected {expected} but received {received}")]
ArgumentCountMismatch { expected: usize, received: usize },
#[error("a conversion error occurred: {0}")]
ConversionError(String),
#[error("an error occurred calling a rust function: {0}")]
RustFunctionError(String),
#[error("an exception was thrown during evaluation: {1}\nStack: {2}")]
Exception(Value, String, String),
#[error("out of memory")]
OutOfMemory,
#[error("an io error occurred: {0}")]
IOError(std::io::Error),
#[error("one or more errors occurred parsing {0}: {1}")]
ParseError(String, String),
}
impl From<NulError> for Error {
fn from(_: NulError) -> Self {
Error::UnexpectedNul
}
}
impl From<std::io::Error> for Error {
fn from(e: std::io::Error) -> Self {
Error::IOError(e)
}
}
pub type Result<T> = core::result::Result<T, Error>;
pub type ValueResult = core::result::Result<Value, Error>;
pub(crate) fn throw_error(context: &ContextRef, error: Error) -> sys::JSValue {
match error {
Error::Exception(v, _, _) => unsafe {
sys::JS_DupValue(context.ctx, v.val);
sys::JS_Throw(context.ctx, v.val)
},
other => throw_string(context, other.to_string()),
}
}
pub(crate) fn throw_string(context: &ContextRef, message: String) -> sys::JSValue {
let ctx = context.ctx;
match context.new_string(&message) {
Ok(e) => unsafe {
// Because context.new_string yields an owned Value, and will
// clean it up on the way out, we need to explicitly DupValue a
// reference for the `Throw` to own.
let err = sys::JS_NewError(ctx);
if sys::JS_ValueGetTag(err) == sys::JS_TAG_EXCEPTION {
// GIVE UP; this is out of memory anyway things probably went
// wrong because of that.
return err;
}
sys::JS_DupValue(ctx, e.val); // SetProperty takes ownership.
let prop = CString::new("message").unwrap();
if sys::JS_SetPropertyStr(ctx, err, prop.as_ptr(), e.val) == -1 {
// Also an out of memory but we need to free the error object
// on our way out.
sys::JS_FreeValue(ctx, err);
return sys::JS_MakeException(); // JS_EXCEPTION
}
sys::JS_Throw(ctx, err)
},
Err(_) => unsafe {
sys::JS_Throw(
ctx,
sys::JS_NewString(ctx, "Errors within errors: embedded nulls in the description of the error that occurred".as_bytes().as_ptr() as *const i8),
)
},
}
}