Misc fixes

lib/runtime-core/src/error.rs

@@ -119,7 +119,6 @@ impl std::error::Error for LinkError {}
 /// The main way to do this is `Instance.call`.
 ///
 /// Comparing two `RuntimeError`s always evaluates to false.
-#[derive(Debug)]
 pub enum RuntimeError {
     Trap { msg: Box<str> },
     Exception { data: Box<[Value]> },
@@ -141,9 +140,25 @@ impl std::fmt::Display for RuntimeError {
             RuntimeError::Exception { ref data } => {
                 write!(f, "Uncaught WebAssembly exception: {:?}", data)
             }
-            RuntimeError::Panic { data: _ } => write!(f, "User-defined \"panic\""),
+            RuntimeError::Panic { data } => {
+                let msg = if let Some(s) = data.downcast_ref::<String>() {
+                    s
+                } else if let Some(s) = data.downcast_ref::<&str>() {
+                    s
+                } else {
+                    "user-defined, opaque"
+                };
+
+                write!(f, "{}", msg)
             }
         }
+    }
+}
+
+impl std::fmt::Debug for RuntimeError {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        write!(f, "{}", self)
+    }
 }
 
 impl std::error::Error for RuntimeError {}
@@ -197,7 +212,6 @@ impl std::error::Error for ResolveError {}
 /// be the `CallError::Runtime(RuntimeError)` variant.
 ///
 /// Comparing two `CallError`s always evaluates to false.
-#[derive(Debug)]
 pub enum CallError {
     Resolve(ResolveError),
     Runtime(RuntimeError),
@@ -218,6 +232,15 @@ impl std::fmt::Display for CallError {
     }
 }
 
+impl std::fmt::Debug for CallError {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        match self {
+            CallError::Resolve(resolve_err) => write!(f, "ResolveError: {:?}", resolve_err),
+            CallError::Runtime(runtime_err) => write!(f, "RuntimeError: {:?}", runtime_err),
+        }
+    }
+}
+
 impl std::error::Error for CallError {}
 
 /// This error type is produced when creating something,

lib/runtime-core/src/types.rs

@@ -129,7 +129,8 @@ unsafe impl WasmExternType for f64 {
 pub unsafe trait ValueType: Copy
 where
     Self: Sized,
-{}
+{
+}
 
 macro_rules! convert_value_impl {
     ($t:ty) => {

lib/wasi/src/state.rs

@@ -8,11 +8,11 @@ use hashbrown::hash_map::{Entry, HashMap};
 use std::{
     cell::{Cell, RefCell},
     ops::{Index, IndexMut},
+    path::PathBuf,
     rc::Rc,
     time::SystemTime,
-    path::PathBuf,
 };
-use zbox::{File, FileType, OpenOptions, Repo, RepoOpener, init_env as zbox_init_env};
+use zbox::{init_env as zbox_init_env, File, FileType, OpenOptions, Repo, RepoOpener};
 
 pub const MAX_SYMLINKS: usize = 100;
 

lib/wasi/src/syscalls/mod.rs

@@ -815,8 +815,8 @@ pub fn poll_oneoff(
 ) -> __wasi_errno_t {
     unimplemented!()
 }
-pub fn proc_exit(ctx: &mut Ctx, rval: __wasi_exitcode_t) {
-    unimplemented!()
+pub fn proc_exit(ctx: &mut Ctx, rval: __wasi_exitcode_t) -> Result<(), &'static str> {
+    Err("Instance exited")
 }
 pub fn proc_raise(ctx: &mut Ctx, sig: __wasi_signal_t) -> __wasi_errno_t {
     unimplemented!()
@@ -833,13 +833,11 @@ pub fn random_get(ctx: &mut Ctx, buf: WasmPtr<u8, Array>, buf_len: u32) -> __was
     let mut rng = thread_rng();
     let memory = ctx.memory(0);
 
-    if let Ok(buf) = buf.deref(memory, 0, buf_len) {
-        for i in 0..(buf_len as usize) {
-            let random_byte = rng.gen::<u8>();
-            buf[i].set(random_byte);
-        }
-    } else {
-        return __WASI_EFAULT;
+    let buf = wasi_try!(buf.deref(memory, 0, buf_len));
+
+    unsafe {
+        let u8_buffer = &mut *(buf as *const [_] as *mut [_] as *mut [u8]);
+        thread_rng().fill(u8_buffer);
     }
 
     __WASI_ESUCCESS