How to set resource limit in wasmtime-go? (#101) (#171)

* How to set resource limit in wasmtime-go? (#101) * Using dev version temporarily --------- Co-authored-by: Vitaly Volkov <[email protected]>
bytecodealliance · Mar 2, 2023 · 6deb799 · 6deb799
1 parent 1e19333
commit 6deb799
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diff --git a/ci/download-wasmtime.py b/ci/download-wasmtime.py
@@ -10,7 +10,7 @@
 import glob
 
 
-version = 'v6.0.0'
+version = 'dev'
 urls = [
     ['wasmtime-{}-x86_64-mingw-c-api.zip', 'windows-x86_64'],
     ['wasmtime-{}-x86_64-linux-c-api.tar.xz', 'linux-x86_64'],

diff --git a/store.go b/store.go
@@ -286,3 +286,23 @@ func (store *Store) ConsumeFuel(fuel uint64) (uint64, error) {
 
 	return uint64(c_remaining), nil
 }
+
+// Limiter provides limits for a store. Used by hosts to limit resource
+// consumption of instances. Use negative value to keep the default value
+// for the limit.
+func (store *Store) Limiter(
+	memorySize int64,
+	tableElements int64,
+	instances int64,
+	tables int64,
+	memories int64,
+) {
+	C.wasmtime_store_limiter(
+		store._ptr,
+		C.int64_t(memorySize),
+		C.int64_t(tableElements),
+		C.int64_t(instances),
+		C.int64_t(tables),
+		C.int64_t(memories),
+	)
+}
diff --git a/store_test.go b/store_test.go
@@ -81,3 +81,41 @@ func TestConsumeFuel(t *testing.T) {
 	require.NoError(t, err)
 	require.Equal(t, (add_fuel - consume_fuel), remaining)
 }
+
+func TestLimiterMemorySizeFail(t *testing.T) {
+	engine := NewEngine()
+	store := NewStore(engine)
+
+	store.Limiter(2*64*1024, -1, -1, -1, -1)
+	wasm, err := Wat2Wasm(`
+	(module
+	  (memory 3)
+	)
+	`)
+	require.NoError(t, err)
+
+	module, err := NewModule(store.Engine, wasm)
+	require.NoError(t, err)
+
+	_, err = NewInstance(store, module, []AsExtern{})
+	require.Error(t, err, "memory minimum size of 3 pages exceeds memory limits")
+}
+
+func TestLimiterMemorySizeSuccess(t *testing.T) {
+	engine := NewEngine()
+	store := NewStore(engine)
+
+	store.Limiter(4*64*1024, -1, -1, -1, -1)
+	wasm, err := Wat2Wasm(`
+	(module
+	  (memory 3)
+	)
+	`)
+	require.NoError(t, err)
+
+	module, err := NewModule(store.Engine, wasm)
+	require.NoError(t, err)
+
+	_, err = NewInstance(store, module, []AsExtern{})
+	require.NoError(t, err)
+}