Initial error refactor

src/host.rs

@@ -3,7 +3,7 @@
 //! still largely reflects that.
 #![allow(non_camel_case_types)]
 #![allow(non_snake_case)]
-use crate::Result;
+use crate::{Error, Result};
 use std::{io, slice, str};
 
 pub type void = ::std::os::raw::c_void;
@@ -500,7 +500,7 @@ pub unsafe fn iovec_to_host_mut<'a>(iovec: &'a mut __wasi_iovec_t) -> io::IoSlic
 /// NB WASI spec requires bytes to be valid UTF-8. Otherwise,
 /// `__WASI_EILSEQ` error is returned.
 pub fn path_from_slice<'a>(s: &'a [u8]) -> Result<&'a str> {
-    str::from_utf8(s).map_err(|_| __WASI_EILSEQ)
+    str::from_utf8(s).map_err(|_| Error::EILSEQ)
 }
 
 /// Creates owned WASI path from byte vector.
@@ -508,7 +508,7 @@ pub fn path_from_slice<'a>(s: &'a [u8]) -> Result<&'a str> {
 /// NB WASI spec requires bytes to be valid UTF-8. Otherwise,
 /// `__WASI_EILSEQ` error is returned.
 pub fn path_from_vec<S: Into<Vec<u8>>>(s: S) -> Result<String> {
-    String::from_utf8(s.into()).map_err(|_| __WASI_EILSEQ)
+    String::from_utf8(s.into()).map_err(|_| Error::EILSEQ)
 }
 
 #[cfg(test)]