runtime: use anyhow::Error instead of Box<dyn std::error::Error...>

crates/runtime/src/instance.rs

@@ -12,6 +12,7 @@ use crate::vmcontext::{
     VMInterrupts, VMMemoryDefinition, VMMemoryImport, VMTableDefinition, VMTableImport,
 };
 use crate::{ExportFunction, ExportGlobal, ExportMemory, ExportTable, Store};
+use anyhow::Error;
 use memoffset::offset_of;
 use more_asserts::assert_lt;
 use std::alloc::Layout;
@@ -348,7 +349,11 @@ impl Instance {
     /// Returns `None` if memory can't be grown by the specified amount
     /// of pages. Returns `Some` with the old size in bytes if growth was
     /// successful.
-    pub(crate) fn memory_grow(&mut self, index: MemoryIndex, delta: u64) -> Option<usize> {
+    pub(crate) fn memory_grow(
+        &mut self,
+        index: MemoryIndex,
+        delta: u64,
+    ) -> Result<Option<usize>, Error> {
         let (idx, instance) = if let Some(idx) = self.module.defined_memory_index(index) {
             (idx, self)
         } else {
@@ -387,7 +392,7 @@ impl Instance {
         table_index: TableIndex,
         delta: u32,
         init_value: TableElement,
-    ) -> Option<u32> {
+    ) -> Result<Option<u32>, Error> {
         let (defined_table_index, instance) =
             self.get_defined_table_index_and_instance(table_index);
         instance.defined_table_grow(defined_table_index, delta, init_value)
@@ -398,7 +403,7 @@ impl Instance {
         table_index: DefinedTableIndex,
         delta: u32,
         init_value: TableElement,
-    ) -> Option<u32> {
+    ) -> Result<Option<u32>, Error> {
         let store = unsafe { &mut *self.store() };
         let table = self
             .tables

crates/runtime/src/lib.rs

@@ -20,7 +20,7 @@
     )
 )]
 
-use std::error::Error;
+use anyhow::Error;
 
 mod export;
 mod externref;
@@ -91,15 +91,25 @@ pub unsafe trait Store {
     ) -> (&mut VMExternRefActivationsTable, &dyn ModuleInfoLookup);
 
     /// Callback invoked to allow the store's resource limiter to reject a memory grow operation.
-    fn memory_growing(&mut self, current: usize, desired: usize, maximum: Option<usize>) -> bool;
+    fn memory_growing(
+        &mut self,
+        current: usize,
+        desired: usize,
+        maximum: Option<usize>,
+    ) -> Result<bool, Error>;
     /// Callback invoked to notify the store's resource limiter that a memory grow operation has
     /// failed.
-    fn memory_grow_failed(&mut self, error: &anyhow::Error);
+    fn memory_grow_failed(&mut self, error: &Error);
     /// Callback invoked to allow the store's resource limiter to reject a table grow operation.
-    fn table_growing(&mut self, current: u32, desired: u32, maximum: Option<u32>) -> bool;
+    fn table_growing(
+        &mut self,
+        current: u32,
+        desired: u32,
+        maximum: Option<u32>,
+    ) -> Result<bool, Error>;
 
     /// Callback invoked whenever fuel runs out by a wasm instance. If an error
     /// is returned that's raised as a trap. Otherwise wasm execution will
     /// continue as normal.
-    fn out_of_gas(&mut self) -> Result<(), Box<dyn Error + Send + Sync>>;
+    fn out_of_gas(&mut self) -> Result<(), Error>;
 }

crates/runtime/src/libcalls.rs

@@ -193,8 +193,9 @@ pub unsafe extern "C" fn wasmtime_memory32_grow(
     let instance = (*vmctx).instance_mut();
     let memory_index = MemoryIndex::from_u32(memory_index);
     match instance.memory_grow(memory_index, delta) {
-        Some(size_in_bytes) => size_in_bytes / (wasmtime_environ::WASM_PAGE_SIZE as usize),
+        Ok(Some(size_in_bytes)) => size_in_bytes / (wasmtime_environ::WASM_PAGE_SIZE as usize),
-        None => usize::max_value(),
+        Ok(None) => usize::max_value(),
+        Err(err) => crate::traphandlers::raise_user_trap(err),
     }
 }
 
@@ -220,9 +221,11 @@ pub unsafe extern "C" fn wasmtime_table_grow(
             init_value.into()
         }
     };
-    instance
+    match instance.table_grow(table_index, delta, element) {
-        .table_grow(table_index, delta, element)
+        Ok(Some(r)) => r,
-        .unwrap_or(-1_i32 as u32)
+        Ok(None) => -1_i32 as u32,
+        Err(err) => crate::traphandlers::raise_user_trap(err),
+    }
 }
 
 /// Implementation of `table.fill`.
@@ -436,15 +439,6 @@ pub unsafe extern "C" fn wasmtime_externref_global_set(
     drop(old);
 }
 
-#[derive(Debug)]
-struct Unimplemented(&'static str);
-impl std::error::Error for Unimplemented {}
-impl std::fmt::Display for Unimplemented {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::result::Result<(), std::fmt::Error> {
-        write!(f, "unimplemented: {}", self.0)
-    }
-}
-
 /// Implementation of `memory.atomic.notify` for locally defined memories.
 pub unsafe extern "C" fn wasmtime_memory_atomic_notify(
     vmctx: *mut VMContext,
@@ -460,9 +454,9 @@ pub unsafe extern "C" fn wasmtime_memory_atomic_notify(
         // just to be sure.
         let addr_to_check = addr.checked_add(4).unwrap();
         validate_atomic_addr(instance, memory, addr_to_check).and_then(|()| {
-            Err(Trap::User(Box::new(Unimplemented(
+            Err(Trap::User(anyhow::anyhow!(
-                "wasm atomics (fn wasmtime_memory_atomic_notify) unsupported",
+                "unimplemented: wasm atomics (fn wasmtime_memory_atomic_notify) unsupported",
-            ))))
+            )))
         })
     };
     match result {
@@ -486,9 +480,9 @@ pub unsafe extern "C" fn wasmtime_memory_atomic_wait32(
         // but we still double-check
         let addr_to_check = addr.checked_add(4).unwrap();
         validate_atomic_addr(instance, memory, addr_to_check).and_then(|()| {
-            Err(Trap::User(Box::new(Unimplemented(
+            Err(Trap::User(anyhow::anyhow!(
-                "wasm atomics (fn wasmtime_memory_atomic_wait32) unsupported",
+                "unimplemented: wasm atomics (fn wasmtime_memory_atomic_wait32) unsupported",
-            ))))
+            )))
         })
     };
     match result {
@@ -512,9 +506,9 @@ pub unsafe extern "C" fn wasmtime_memory_atomic_wait64(
         // but we still double-check
         let addr_to_check = addr.checked_add(8).unwrap();
         validate_atomic_addr(instance, memory, addr_to_check).and_then(|()| {
-            Err(Trap::User(Box::new(Unimplemented(
+            Err(Trap::User(anyhow::anyhow!(
-                "wasm atomics (fn wasmtime_memory_atomic_wait64) unsupported",
+                "unimplemented: wasm atomics (fn wasmtime_memory_atomic_wait64) unsupported",
-            ))))
+            )))
         })
     };
     match result {

crates/runtime/src/memory.rs

@@ -5,6 +5,7 @@
 use crate::mmap::Mmap;
 use crate::vmcontext::VMMemoryDefinition;
 use crate::Store;
+use anyhow::Error;
 use anyhow::{bail, format_err, Result};
 use more_asserts::{assert_ge, assert_le};
 use std::convert::TryFrom;
@@ -315,7 +316,7 @@ impl Memory {
         // calculation overflowed. This means that the `minimum` we're informing
         // the limiter is lossy and may not be 100% accurate, but for now the
         // expected uses of limiter means that's ok.
-        if !store.memory_growing(0, minimum.unwrap_or(absolute_max), maximum) {
+        if !store.memory_growing(0, minimum.unwrap_or(absolute_max), maximum)? {
             bail!(
                 "memory minimum size of {} pages exceeds memory limits",
                 plan.memory.minimum
@@ -377,11 +378,15 @@ impl Memory {
     ///
     /// Generally, prefer using `InstanceHandle::memory_grow`, which encapsulates
     /// this unsafety.
-    pub unsafe fn grow(&mut self, delta_pages: u64, store: &mut dyn Store) -> Option<usize> {
+    pub unsafe fn grow(
+        &mut self,
+        delta_pages: u64,
+        store: &mut dyn Store,
+    ) -> Result<Option<usize>, Error> {
         let old_byte_size = self.byte_size();
         // Wasm spec: when growing by 0 pages, always return the current size.
         if delta_pages == 0 {
-            return Some(old_byte_size);
+            return Ok(Some(old_byte_size));
         }
 
         // largest wasm-page-aligned region of memory it is possible to
@@ -402,15 +407,15 @@ impl Memory {
 
         let maximum = self.maximum_byte_size();
         // Store limiter gets first chance to reject memory_growing.
-        if !store.memory_growing(old_byte_size, new_byte_size, maximum) {
+        if !store.memory_growing(old_byte_size, new_byte_size, maximum)? {
-            return None;
+            return Ok(None);
         }
 
         // Never exceed maximum, even if limiter permitted it.
         if let Some(max) = maximum {
             if new_byte_size > max {
                 store.memory_grow_failed(&format_err!("Memory maximum size exceeded"));
-                return None;
+                return Ok(None);
             }
         }
 
@@ -418,7 +423,10 @@ impl Memory {
         {
             if self.is_static() {
                 // Reset any faulted guard pages before growing the memory.
-                self.reset_guard_pages().ok()?;
+                if let Err(e) = self.reset_guard_pages() {
+                    store.memory_grow_failed(&e);
+                    return Ok(None);
+                }
             }
         }
 
@@ -432,24 +440,27 @@ impl Memory {
                 // Never exceed static memory size
                 if new_byte_size > base.len() {
                     store.memory_grow_failed(&format_err!("static memory size exceeded"));
-                    return None;
+                    return Ok(None);
                 }
 
                 // Operating system can fail to make memory accessible
-                let r = make_accessible(
+                if let Err(e) = make_accessible(
                     base.as_mut_ptr().add(old_byte_size),
                     new_byte_size - old_byte_size,
-                );
+                ) {
-                r.map_err(|e| store.memory_grow_failed(&e)).ok()?;
+                    store.memory_grow_failed(&e);
-
+                    return Ok(None);
+                }
                 *size = new_byte_size;
             }
             Memory::Dynamic(mem) => {
-                let r = mem.grow_to(new_byte_size);
+                if let Err(e) = mem.grow_to(new_byte_size) {
-                r.map_err(|e| store.memory_grow_failed(&e)).ok()?;
+                    store.memory_grow_failed(&e);
+                    return Ok(None);
+                }
             }
         }
-        Some(old_byte_size)
+        Ok(Some(old_byte_size))
     }
 
     /// Return a `VMMemoryDefinition` for exposing the memory to compiled wasm code.

crates/runtime/src/table.rs

@@ -4,6 +4,7 @@
 
 use crate::vmcontext::{VMCallerCheckedAnyfunc, VMTableDefinition};
 use crate::{Store, Trap, VMExternRef};
+use anyhow::Error;
 use anyhow::{bail, Result};
 use std::convert::{TryFrom, TryInto};
 use std::ops::Range;
@@ -168,7 +169,7 @@ impl Table {
     }
 
     fn limit_new(plan: &TablePlan, store: &mut dyn Store) -> Result<()> {
-        if !store.table_growing(0, plan.table.minimum, plan.table.maximum) {
+        if !store.table_growing(0, plan.table.minimum, plan.table.maximum)? {
             bail!(
                 "table minimum size of {} elements exceeds table limits",
                 plan.table.minimum
@@ -288,17 +289,20 @@ impl Table {
         delta: u32,
         init_value: TableElement,
         store: &mut dyn Store,
-    ) -> Option<u32> {
+    ) -> Result<Option<u32>, Error> {
         let old_size = self.size();
-        let new_size = old_size.checked_add(delta)?;
+        let new_size = match old_size.checked_add(delta) {
+            Some(s) => s,
+            None => return Ok(None),
+        };
 
-        if !store.table_growing(old_size, new_size, self.maximum()) {
+        if !store.table_growing(old_size, new_size, self.maximum())? {
-            return None;
+            return Ok(None);
         }
 
         if let Some(max) = self.maximum() {
             if new_size > max {
-                return None;
+                return Ok(None);
             }
         }
 
@@ -320,7 +324,7 @@ impl Table {
         self.fill(old_size, init_value, delta)
             .expect("table should not be out of bounds");
 
-        Some(old_size)
+        Ok(Some(old_size))
     }
 
     /// Get reference to the specified element.

crates/runtime/src/traphandlers.rs

@@ -2,10 +2,10 @@
 //! signalhandling mechanisms.
 
 use crate::{VMContext, VMInterrupts};
+use anyhow::Error;
 use backtrace::Backtrace;
 use std::any::Any;
 use std::cell::{Cell, UnsafeCell};
-use std::error::Error;
 use std::mem::MaybeUninit;
 use std::ptr;
 use std::sync::atomic::Ordering::SeqCst;
@@ -80,7 +80,7 @@ pub fn init_traps(is_wasm_pc: fn(usize) -> bool) {
 /// Only safe to call when wasm code is on the stack, aka `catch_traps` must
 /// have been previously called. Additionally no Rust destructors can be on the
 /// stack. They will be skipped and not executed.
-pub unsafe fn raise_user_trap(data: Box<dyn Error + Send + Sync>) -> ! {
+pub unsafe fn raise_user_trap(data: Error) -> ! {
     tls::with(|info| info.unwrap().unwind_with(UnwindReason::UserTrap(data)))
 }
 
@@ -114,7 +114,7 @@ pub unsafe fn resume_panic(payload: Box<dyn Any + Send>) -> ! {
 #[derive(Debug)]
 pub enum Trap {
     /// A user-raised trap through `raise_user_trap`.
-    User(Box<dyn Error + Send + Sync>),
+    User(Error),
 
     /// A trap raised from jit code
     Jit {
@@ -206,7 +206,7 @@ pub struct CallThreadState {
 
 enum UnwindReason {
     Panic(Box<dyn Any + Send>),
-    UserTrap(Box<dyn Error + Send + Sync>),
+    UserTrap(Error),
     LibTrap(Trap),
     JitTrap { backtrace: Backtrace, pc: usize },
 }