builtins: TextEncoder, TextDecoder, URL shared builtins (#438)

Author: Guy Bedford

c-dependencies/js-compute-runtime/.gitignore

@@ -4,3 +4,4 @@
 
 /js-compute-runtime*.wasm
 /build
+/shared

c-dependencies/js-compute-runtime/Makefile

@@ -154,6 +154,9 @@ $(OBJ_DIR)/core:
 $(OBJ_DIR)/host_interface:
 	$(call cmd,mkdir,$@)
 
+shared:
+	$(call cmd,mkdir,$@)
+
 # Downloaded dependencies ######################################################
 
 $(BUILD)/openssl-$(OPENSSL_VERSION).tar.gz: URL=https://www.openssl.org/source/openssl-$(OPENSSL_VERSION).tar.gz
@@ -283,12 +286,15 @@ $(OBJ_DIR)/js-compute-runtime-component.wasm: $(OBJ_DIR)/xqd-world/xqd_world_ada
 	$(WASI_CXX) $(LD_FLAGS) $(OPENSSL_LIBS) -o $@ $^
 	$(call cmd_format,WASM_STRIP,$@) $(call WASM_STRIP,$@)
 
-# The subset of javascript builtins that are reusable across other runtimes.
-shared-builtins.a: $(OBJ_DIR)/shared-builtins.a
-	$(call cmd,cp,$@)
+# Shared builtins build
 
-$(OBJ_DIR)/shared-builtins.a: $(OBJ_DIR)/builtins/shared/console.o $(OBJ_DIR)/builtin.o
-	$(call cmd,wasi_ar,$@)
+shared-builtins: shared/builtins.a shared/librust_url.a
+
+shared/builtins.a: $(OBJ_DIR)/builtins/shared/*.o $(OBJ_DIR)/builtin.o | shared
+	$(call cmd,wasi_ar,$^)
+
+shared/librust_url.a: $(RUST_URL_LIB) | shared
+	$(call cmd,cp,$@)
 
 # These two rules copy the built artifacts into the $(FSM_SRC) directory, and
 # are both marked phony as we need to do the right thing when running the

c-dependencies/js-compute-runtime/builtin-error-numbers.msg

@@ -44,4 +44,5 @@ MSG_DEF(JSMSG_BUILTIN_CTOR_NO_NEW,                             1, JSEXN_TYPEERR,
 MSG_DEF(JSMSG_ILLEGAL_CTOR,                                    0, JSEXN_TYPEERR, "Illegal constructor")
 MSG_DEF(JSMSG_INVALID_INTERFACE,                               2, JSEXN_TYPEERR, "'{0}' called on an object that does not implement interface {1}")
 MSG_DEF(JSMSG_INCOMPATIBLE_INSTANCE,                           2, JSEXN_TYPEERR, "Method {0} called on receiver that's not an instance of {1}")
+MSG_DEF(JSMSG_INVALID_BUFFER_ARG,                              2, JSEXN_TYPEERR, "{0} must be of type ArrayBuffer or ArrayBufferView but got \"{1}\"")
 //clang-format on

c-dependencies/js-compute-runtime/builtin.cpp

@@ -8,6 +8,29 @@ const JSErrorFormatString *GetErrorMessageBuiltin(void *userRef, unsigned errorN
   return nullptr;
 }
 
+std::optional<std::span<uint8_t>> value_to_buffer(JSContext *cx, JS::HandleValue val,
+                                                  const char *val_desc) {
+  if (!val.isObject() ||
+      !(JS_IsArrayBufferViewObject(&val.toObject()) || JS::IsArrayBufferObject(&val.toObject()))) {
+    JS_ReportErrorNumberUTF8(cx, GetErrorMessageBuiltin, nullptr, JSMSG_INVALID_BUFFER_ARG,
+                             val_desc, val.type());
+    return std::nullopt;
+  }
+
+  JS::RootedObject input(cx, &val.toObject());
+  uint8_t *data;
+  bool is_shared;
+  size_t len = 0;
+
+  if (JS_IsArrayBufferViewObject(input)) {
+    js::GetArrayBufferViewLengthAndData(input, &len, &is_shared, &data);
+  } else {
+    JS::GetArrayBufferLengthAndData(input, &len, &is_shared, &data);
+  }
+
+  return std::span(data, len);
+}
+
 JS::UniqueChars encode(JSContext *cx, JS::HandleString str, size_t *encoded_len) {
   JS::UniqueChars text = JS_EncodeStringToUTF8(cx, str);
   if (!text)

c-dependencies/js-compute-runtime/builtin.h

@@ -7,16 +7,22 @@
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Winvalid-offsetof"
 #pragma clang diagnostic ignored "-Wdeprecated-enum-enum-conversion"
+#include "js/ArrayBuffer.h"
 #include "js/Conversions.h"
 #include "js/ForOfIterator.h"
 #include "js/Object.h"
 #include "js/Promise.h"
+#include "js/experimental/TypedData.h"
 #include "jsapi.h"
 #include "jsfriendapi.h"
 #include "rust-url/rust-url.h"
+#include <span>
 
 #pragma clang diagnostic pop
 
+std::optional<std::span<uint8_t>> value_to_buffer(JSContext *cx, JS::HandleValue val,
+                                                  const char *val_desc);
+
 // TODO(performance): introduce a version that writes into an existing buffer, and use that
 // with the hostcall buffer where possible.
 // https://github.com/fastly/js-compute-runtime/issues/215

c-dependencies/js-compute-runtime/builtins/fastly.cpp

@@ -12,7 +12,7 @@
 #include "builtins/env.h"
 #include "builtins/fastly.h"
 #include "builtins/logger.h"
-#include "builtins/url.h"
+#include "builtins/shared/url.h"
 #include "core/geo_ip.h"
 #include "host_interface/host_call.h"
 

c-dependencies/js-compute-runtime/builtins/fetch-event.cpp

@@ -2,7 +2,7 @@
 #include "builtins/client-info.h"
 #include "builtins/fastly.h"
 #include "builtins/request-response.h"
-#include "builtins/url.h"
+#include "builtins/shared/url.h"
 #include "builtins/worker-location.h"
 #include "host_interface/host_api.h"
 #include "xqd-world/xqd_world_adapter.h"

c-dependencies/js-compute-runtime/builtins/object-store.cpp

@@ -17,7 +17,7 @@
 #include "builtin.h"
 #include "builtins/native-stream-source.h"
 #include "builtins/object-store.h"
-#include "builtins/url.h"
+#include "builtins/shared/url.h"
 #include "host_interface/host_api.h"
 #include "host_interface/host_call.h"
 #include "js-compute-builtins.h"

c-dependencies/js-compute-runtime/builtins/request-response.cpp

@@ -6,8 +6,8 @@
 #include "builtins/fetch-event.h"
 #include "builtins/native-stream-source.h"
 #include "builtins/object-store.h"
+#include "builtins/shared/url.h"
 #include "builtins/transform-stream.h"
-#include "builtins/url.h"
 #include "host_interface/host_api.h"
 #include "third_party/picosha2.h"
 

c-dependencies/js-compute-runtime/builtins/text-decoder.cpp renamed to c-dependencies/js-compute-runtime/builtins/shared/text-decoder.cpp

@@ -1,5 +1,5 @@
-#include "builtins/text-decoder.h"
-#include "js-compute-builtins.h"
+#include "builtins/shared/text-decoder.h"
+#include "builtin.h"
 
 namespace builtins {