// Copyright 2004-present Facebook. All Rights Reserved. #include #include "Value.h" #include "JSCHelpers.h" #include "JavaScriptCore.h" // See the comment under Value::fromDynamic() #if !defined(__APPLE__) && defined(WITH_FB_JSC_TUNING) #define USE_FAST_FOLLY_DYNAMIC_CONVERSION 1 #else #define USE_FAST_FOLLY_DYNAMIC_CONVERSION 0 #endif namespace facebook { namespace react { Value::Value(JSContextRef context, JSValueRef value) : m_context(context), m_value(value) {} Value::Value(JSContextRef context, JSStringRef str) : m_context(context), m_value(JSC_JSValueMakeString(context, str)) {} JSContextRef Value::context() const { return m_context; } std::string Value::toJSONString(unsigned indent) const { JSValueRef exn; auto stringToAdopt = JSC_JSValueCreateJSONString(m_context, m_value, indent, &exn); if (!stringToAdopt) { throw JSException(m_context, exn, "Exception creating JSON string"); } return String::adopt(m_context, stringToAdopt).str(); } /* static */ Value Value::fromJSON(JSContextRef ctx, const String& json) { auto result = JSC_JSValueMakeFromJSONString(ctx, json); if (!result) { throw JSException("Failed to create Value from JSON: %s", json.str().c_str()); } return Value(ctx, result); } Value Value::fromDynamic(JSContextRef ctx, const folly::dynamic& value) { // JavaScriptCore's iOS APIs have their own version of this direct conversion. // In addition, using this requires exposing some of JSC's private APIs, // so it's limited to non-apple platforms and to builds that use the custom JSC. // Otherwise, we use the old way of converting through JSON. #if USE_FAST_FOLLY_DYNAMIC_CONVERSION // Defer GC during the creation of the JSValue, as we don't want // intermediate objects to be collected. // We could use JSValueProtect(), but it will make the process much slower. JSDeferredGCRef deferGC = JSDeferGarbageCollection(ctx); // Set a global lock for the whole process, // instead of re-acquiring the lock for each operation. JSLock(ctx); JSValueRef jsVal = Value::fromDynamicInner(ctx, value); JSUnlock(ctx); JSResumeGarbageCollection(ctx, deferGC); return Value(ctx, jsVal); #else auto json = folly::toJson(value); return fromJSON(ctx, String(ctx, json.c_str())); #endif } JSValueRef Value::fromDynamicInner(JSContextRef ctx, const folly::dynamic& obj) { switch (obj.type()) { // For primitive types (and strings), just create and return an equivalent JSValue case folly::dynamic::Type::NULLT: return JSC_JSValueMakeNull(ctx); case folly::dynamic::Type::BOOL: return JSC_JSValueMakeBoolean(ctx, obj.getBool()); case folly::dynamic::Type::DOUBLE: return JSC_JSValueMakeNumber(ctx, obj.getDouble()); case folly::dynamic::Type::INT64: return JSC_JSValueMakeNumber(ctx, obj.asDouble()); case folly::dynamic::Type::STRING: return JSC_JSValueMakeString(ctx, String(ctx, obj.getString().c_str())); case folly::dynamic::Type::ARRAY: { // Collect JSValue for every element in the array JSValueRef vals[obj.size()]; for (size_t i = 0; i < obj.size(); ++i) { vals[i] = fromDynamicInner(ctx, obj[i]); } // Create a JSArray with the values JSValueRef arr = JSC_JSObjectMakeArray(ctx, obj.size(), vals, nullptr); return arr; } case folly::dynamic::Type::OBJECT: { // Create an empty object JSObjectRef jsObj = JSC_JSObjectMake(ctx, nullptr, nullptr); // Create a JSValue for each of the object's children and set them in the object for (auto it = obj.items().begin(); it != obj.items().end(); ++it) { JSC_JSObjectSetProperty( ctx, jsObj, String(ctx, it->first.asString().c_str()), fromDynamicInner(ctx, it->second), kJSPropertyAttributeNone, nullptr); } return jsObj; } default: // Assert not reached LOG(FATAL) << "Trying to convert a folly object of unsupported type."; return JSC_JSValueMakeNull(ctx); } } Object Value::asObject() const { JSValueRef exn; JSObjectRef jsObj = JSC_JSValueToObject(context(), m_value, &exn); if (!jsObj) { throw JSException(m_context, exn, "Failed to convert to object"); } return Object(context(), jsObj); } String Value::toString() const { JSValueRef exn; JSStringRef jsStr = JSC_JSValueToStringCopy(context(), m_value, &exn); if (!jsStr) { throw JSException(m_context, exn, "Failed to convert to string"); } return String::adopt(context(), jsStr); } Value Value::makeError(JSContextRef ctx, const char *error) { JSValueRef exn; JSValueRef args[] = { Value(ctx, String(ctx, error)) }; JSObjectRef errorObj = JSC_JSObjectMakeError(ctx, 1, args, &exn); if (!errorObj) { throw JSException(ctx, exn, "Exception making error"); } return Value(ctx, errorObj); } Object::operator Value() const { return Value(m_context, m_obj); } Value Object::callAsFunction(std::initializer_list args) const { return callAsFunction(nullptr, args.size(), args.begin()); } Value Object::callAsFunction(const Object& thisObj, std::initializer_list args) const { return callAsFunction((JSObjectRef)thisObj, args.size(), args.begin()); } Value Object::callAsFunction(int nArgs, const JSValueRef args[]) const { return callAsFunction(nullptr, nArgs, args); } Value Object::callAsFunction(const Object& thisObj, int nArgs, const JSValueRef args[]) const { return callAsFunction(static_cast(thisObj), nArgs, args); } Value Object::callAsFunction(JSObjectRef thisObj, int nArgs, const JSValueRef args[]) const { JSValueRef exn; JSValueRef result = JSC_JSObjectCallAsFunction(m_context, m_obj, thisObj, nArgs, args, &exn); if (!result) { throw JSException(m_context, exn, "Exception calling object as function"); } return Value(m_context, result); } Object Object::callAsConstructor(std::initializer_list args) const { JSValueRef exn; JSObjectRef result = JSC_JSObjectCallAsConstructor(m_context, m_obj, args.size(), args.begin(), &exn); if (!result) { throw JSException(m_context, exn, "Exception calling object as constructor"); } return Object(m_context, result); } Value Object::getProperty(const String& propName) const { JSValueRef exn; JSValueRef property = JSC_JSObjectGetProperty(m_context, m_obj, propName, &exn); if (!property) { throw JSException(m_context, exn, nullptr, "Failed to get property '%s'", propName.str().c_str()); } return Value(m_context, property); } Value Object::getPropertyAtIndex(unsigned int index) const { JSValueRef exn; JSValueRef property = JSC_JSObjectGetPropertyAtIndex(m_context, m_obj, index, &exn); if (!property) { throw JSException(m_context, exn, nullptr, "Failed to get property at index %d", index); } return Value(m_context, property); } Value Object::getProperty(const char *propName) const { return getProperty(String(m_context, propName)); } void Object::setProperty(const String& propName, const Value& value) { JSValueRef exn = nullptr; JSC_JSObjectSetProperty(m_context, m_obj, propName, value, kJSPropertyAttributeNone, &exn); if (exn) { throw JSException(m_context, exn, nullptr, "Failed to set property '%s'", propName.str().c_str()); } } void Object::setPropertyAtIndex(unsigned int index, const Value& value) { JSValueRef exn = nullptr; JSC_JSObjectSetPropertyAtIndex(m_context, m_obj, index, value, &exn); if (exn) { throw JSException(m_context, exn, nullptr, "Failed to set property at index %d", index); } } void Object::setProperty(const char *propName, const Value& value) { setProperty(String(m_context, propName), value); } std::vector Object::getPropertyNames() const { auto namesRef = JSC_JSObjectCopyPropertyNames(m_context, m_obj); size_t count = JSC_JSPropertyNameArrayGetCount(m_context, namesRef); std::vector names; names.reserve(count); for (size_t i = 0; i < count; i++) { names.emplace_back(String::ref(m_context, JSC_JSPropertyNameArrayGetNameAtIndex(m_context, namesRef, i))); } JSC_JSPropertyNameArrayRelease(m_context, namesRef); return names; } std::unordered_map Object::toJSONMap() const { std::unordered_map map; auto namesRef = JSC_JSObjectCopyPropertyNames(m_context, m_obj); size_t count = JSC_JSPropertyNameArrayGetCount(m_context, namesRef); for (size_t i = 0; i < count; i++) { auto key = String::ref(m_context, JSC_JSPropertyNameArrayGetNameAtIndex(m_context, namesRef, i)); map.emplace(key.str(), getProperty(key).toJSONString()); } JSC_JSPropertyNameArrayRelease(m_context, namesRef); return map; } /* static */ Object Object::create(JSContextRef ctx) { JSObjectRef newObj = JSC_JSObjectMake( ctx, NULL, // create instance of default object class NULL); // no private data return Object(ctx, newObj); } } }