Expose features option in C API binary reading (#6380)

This allows reading a module that requires a particular
feature set. The old API assumed only MVP features.

Author: surma

CHANGELOG.md

@@ -18,6 +18,8 @@ Current Trunk
  - (If new wat parser is enabled) Source map comments on `else` branches must
    now be placed above the instruction inside the `else` branch rather than on
    the `else` branch itself.
+ - Add a new `BinaryenModuleReadWithFeatures` function to the C API that allows
+   to configure which features to enable in the parser.
 
 v117
 ----

src/binaryen-c.cpp

@@ -5851,14 +5851,15 @@ char* BinaryenModuleAllocateAndWriteStackIR(BinaryenModuleRef module,
   return output;
 }
 
-BinaryenModuleRef BinaryenModuleRead(char* input, size_t inputSize) {
+BinaryenModuleRef BinaryenModuleReadWithFeatures(char* input,
+                                                 size_t inputSize,
+                                                 BinaryenFeatures features) {
   auto* wasm = new Module;
   std::vector<char> buffer(false);
   buffer.resize(inputSize);
   std::copy_n(input, inputSize, buffer.begin());
   try {
-    // TODO: allow providing features in the C API
-    WasmBinaryReader parser(*wasm, FeatureSet::MVP, buffer);
+    WasmBinaryReader parser(*wasm, features, buffer);
     parser.read();
   } catch (ParseException& p) {
     p.dump(std::cerr);
@@ -5867,6 +5868,10 @@ BinaryenModuleRef BinaryenModuleRead(char* input, size_t inputSize) {
   return wasm;
 }
 
+BinaryenModuleRef BinaryenModuleRead(char* input, size_t inputSize) {
+  return BinaryenModuleReadWithFeatures(input, inputSize, BinaryenFeatureMVP());
+}
+
 void BinaryenModuleInterpret(BinaryenModuleRef module) {
   ShellExternalInterface interface;
   ModuleRunner instance(*(Module*)module, &interface, {});

src/binaryen-c.h

@@ -3175,10 +3175,14 @@ BINARYEN_API char* BinaryenModuleAllocateAndWriteText(BinaryenModuleRef module);
 BINARYEN_API char*
 BinaryenModuleAllocateAndWriteStackIR(BinaryenModuleRef module, bool optimize);
 
-// Deserialize a module from binary form.
+// Deserialize a module from binary form, assuming the MVP feature set.
 BINARYEN_API BinaryenModuleRef BinaryenModuleRead(char* input,
                                                   size_t inputSize);
 
+// Deserialize a module from binary form, enabling the given feature set.
+BINARYEN_API BinaryenModuleRef BinaryenModuleReadWithFeatures(
+  char* input, size_t inputSize, BinaryenFeatures featureSet);
+
 // Execute a module in the Binaryen interpreter. This will create an instance of
 // the module, run it in the interpreter - which means running the start method
 // - and then destroying the instance.

test/example/c-api-kitchen-sink.c

@@ -401,6 +401,32 @@ void test_features() {
   printf("BinaryenFeatureAll: %d\n", BinaryenFeatureAll());
 }
 
+void test_read_with_feature() {
+  BinaryenModuleRef module = BinaryenModuleCreate();
+  // Having multiple tables makes this module inherently not MVP compatible
+  // and requires the externref feature enabled to parse successfully.
+  BinaryenAddTable(module, "tab", 0, 100, BinaryenTypeFuncref());
+  BinaryenAddTable(module, "tab2", 0, 100, BinaryenTypeFuncref());
+
+  BinaryenFeatures features =
+    BinaryenFeatureMVP() | BinaryenFeatureReferenceTypes();
+  BinaryenModuleSetFeatures(module, features);
+
+  size_t bufferSize = 1024;
+  char* buffer = malloc(bufferSize);
+  size_t written = BinaryenModuleWrite(module, buffer, bufferSize);
+  BinaryenModuleDispose(module);
+
+  // See we can read the bytes and get a valid module from there.
+  BinaryenModuleRef readModule =
+    BinaryenModuleReadWithFeatures(buffer, written, features);
+  int valid = BinaryenModuleValidate(readModule);
+  assert(valid);
+  BinaryenModuleDispose(readModule);
+
+  free(buffer);
+}
+
 void test_core() {
 
   // Module creation