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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: set ts=8 sw=2 et tw=80:
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#include "vm/ErrorObject-inl.h"
#include "mozilla/Assertions.h"
#include "mozilla/Attributes.h"
#include "mozilla/DebugOnly.h"
#include "mozilla/Maybe.h"
#include <utility>
#include "jsexn.h"
#include "jspubtd.h"
#include "NamespaceImports.h"
#include "gc/AllocKind.h"
#include "gc/GCContext.h"
#include "js/CallArgs.h"
#include "js/CallNonGenericMethod.h"
#include "js/CharacterEncoding.h" // JS::ConstUTF8CharsZ
#include "js/Class.h"
#include "js/ColumnNumber.h" // JS::ColumnNumberOneOrigin
#include "js/Conversions.h"
#include "js/ErrorReport.h"
#include "js/friend/ErrorMessages.h" // js::GetErrorMessage, JSMSG_*
#include "js/friend/StackLimits.h" // js::AutoCheckRecursionLimit
#include "js/PropertySpec.h"
#include "js/RootingAPI.h"
#include "js/Stack.h"
#include "js/TypeDecls.h"
#include "js/Utility.h"
#include "js/Value.h"
#include "js/Wrapper.h"
#include "util/StringBuffer.h"
#include "vm/GlobalObject.h"
#include "vm/Iteration.h"
#include "vm/JSAtomUtils.h" // ClassName
#include "vm/JSFunction.h"
#include "vm/JSObject.h"
#include "vm/NativeObject.h"
#include "vm/ObjectOperations.h"
#include "vm/SavedStacks.h"
#include "vm/SelfHosting.h"
#include "vm/Shape.h"
#include "vm/Stack.h"
#include "vm/StringType.h"
#include "vm/ToSource.h" // js::ValueToSource
#include "vm/JSContext-inl.h"
#include "vm/JSObject-inl.h"
#include "vm/ObjectOperations-inl.h"
#include "vm/SavedStacks-inl.h"
#include "vm/Shape-inl.h"
using namespace js;
#define IMPLEMENT_ERROR_PROTO_CLASS(name) \
{ \
#name ".prototype", JSCLASS_HAS_CACHED_PROTO(JSProto_##name), \
JS_NULL_CLASS_OPS, \
&ErrorObject::classSpecs[JSProto_##name - JSProto_Error] \
}
const JSClass ErrorObject::protoClasses[JSEXN_ERROR_LIMIT] = {
IMPLEMENT_ERROR_PROTO_CLASS(Error),
IMPLEMENT_ERROR_PROTO_CLASS(InternalError),
IMPLEMENT_ERROR_PROTO_CLASS(AggregateError),
IMPLEMENT_ERROR_PROTO_CLASS(EvalError),
IMPLEMENT_ERROR_PROTO_CLASS(RangeError),
IMPLEMENT_ERROR_PROTO_CLASS(ReferenceError),
IMPLEMENT_ERROR_PROTO_CLASS(SyntaxError),
IMPLEMENT_ERROR_PROTO_CLASS(TypeError),
IMPLEMENT_ERROR_PROTO_CLASS(URIError),
IMPLEMENT_ERROR_PROTO_CLASS(DebuggeeWouldRun),
IMPLEMENT_ERROR_PROTO_CLASS(CompileError),
IMPLEMENT_ERROR_PROTO_CLASS(LinkError),
IMPLEMENT_ERROR_PROTO_CLASS(RuntimeError)};
static bool exn_toSource(JSContext* cx, unsigned argc, Value* vp);
static const JSFunctionSpec error_methods[] = {
JS_FN("toSource", exn_toSource, 0, 0),
JS_SELF_HOSTED_FN("toString", "ErrorToString", 0, 0), JS_FS_END};
// Error.prototype and NativeError.prototype have own .message and .name
// properties.
#define COMMON_ERROR_PROPERTIES(name) \
JS_STRING_PS("message", "", 0), JS_STRING_PS("name", #name, 0)
static const JSPropertySpec error_properties[] = {
COMMON_ERROR_PROPERTIES(Error),
// Only Error.prototype has .stack!
JS_PSGS("stack", ErrorObject::getStack, ErrorObject::setStack, 0),
JS_PS_END};
#define IMPLEMENT_NATIVE_ERROR_PROPERTIES(name) \
static const JSPropertySpec name##_properties[] = { \
COMMON_ERROR_PROPERTIES(name), JS_PS_END};
IMPLEMENT_NATIVE_ERROR_PROPERTIES(InternalError)
IMPLEMENT_NATIVE_ERROR_PROPERTIES(AggregateError)
IMPLEMENT_NATIVE_ERROR_PROPERTIES(EvalError)
IMPLEMENT_NATIVE_ERROR_PROPERTIES(RangeError)
IMPLEMENT_NATIVE_ERROR_PROPERTIES(ReferenceError)
IMPLEMENT_NATIVE_ERROR_PROPERTIES(SyntaxError)
IMPLEMENT_NATIVE_ERROR_PROPERTIES(TypeError)
IMPLEMENT_NATIVE_ERROR_PROPERTIES(URIError)
IMPLEMENT_NATIVE_ERROR_PROPERTIES(DebuggeeWouldRun)
IMPLEMENT_NATIVE_ERROR_PROPERTIES(CompileError)
IMPLEMENT_NATIVE_ERROR_PROPERTIES(LinkError)
IMPLEMENT_NATIVE_ERROR_PROPERTIES(RuntimeError)
#define IMPLEMENT_NATIVE_ERROR_SPEC(name) \
{ \
ErrorObject::createConstructor, ErrorObject::createProto, nullptr, \
nullptr, nullptr, name##_properties, nullptr, JSProto_Error \
}
#define IMPLEMENT_NONGLOBAL_ERROR_SPEC(name) \
{ \
ErrorObject::createConstructor, ErrorObject::createProto, nullptr, \
nullptr, nullptr, name##_properties, nullptr, \
JSProto_Error | ClassSpec::DontDefineConstructor \
}
const ClassSpec ErrorObject::classSpecs[JSEXN_ERROR_LIMIT] = {
{ErrorObject::createConstructor, ErrorObject::createProto, nullptr, nullptr,
error_methods, error_properties},
IMPLEMENT_NATIVE_ERROR_SPEC(InternalError),
IMPLEMENT_NATIVE_ERROR_SPEC(AggregateError),
IMPLEMENT_NATIVE_ERROR_SPEC(EvalError),
IMPLEMENT_NATIVE_ERROR_SPEC(RangeError),
IMPLEMENT_NATIVE_ERROR_SPEC(ReferenceError),
IMPLEMENT_NATIVE_ERROR_SPEC(SyntaxError),
IMPLEMENT_NATIVE_ERROR_SPEC(TypeError),
IMPLEMENT_NATIVE_ERROR_SPEC(URIError),
IMPLEMENT_NONGLOBAL_ERROR_SPEC(DebuggeeWouldRun),
IMPLEMENT_NONGLOBAL_ERROR_SPEC(CompileError),
IMPLEMENT_NONGLOBAL_ERROR_SPEC(LinkError),
IMPLEMENT_NONGLOBAL_ERROR_SPEC(RuntimeError)};
#define IMPLEMENT_ERROR_CLASS_CORE(name, reserved_slots) \
{ \
#name, \
JSCLASS_HAS_CACHED_PROTO(JSProto_##name) | \
JSCLASS_HAS_RESERVED_SLOTS(reserved_slots) | \
JSCLASS_BACKGROUND_FINALIZE, \
&ErrorObjectClassOps, \
&ErrorObject::classSpecs[JSProto_##name - JSProto_Error] \
}
#define IMPLEMENT_ERROR_CLASS(name) \
IMPLEMENT_ERROR_CLASS_CORE(name, ErrorObject::RESERVED_SLOTS)
// Only used for classes that could be a Wasm trap. Classes that use this
// macro should be kept in sync with the exception types that mightBeWasmTrap()
// will return true for.
#define IMPLEMENT_ERROR_CLASS_MAYBE_WASM_TRAP(name) \
IMPLEMENT_ERROR_CLASS_CORE(name, ErrorObject::RESERVED_SLOTS_MAYBE_WASM_TRAP)
static void exn_finalize(JS::GCContext* gcx, JSObject* obj);
static const JSClassOps ErrorObjectClassOps = {
nullptr, // addProperty
nullptr, // delProperty
nullptr, // enumerate
nullptr, // newEnumerate
nullptr, // resolve
nullptr, // mayResolve
exn_finalize, // finalize
nullptr, // call
nullptr, // construct
nullptr, // trace
};
const JSClass ErrorObject::classes[JSEXN_ERROR_LIMIT] = {
IMPLEMENT_ERROR_CLASS(Error),
IMPLEMENT_ERROR_CLASS_MAYBE_WASM_TRAP(InternalError),
IMPLEMENT_ERROR_CLASS(AggregateError), IMPLEMENT_ERROR_CLASS(EvalError),
IMPLEMENT_ERROR_CLASS(RangeError), IMPLEMENT_ERROR_CLASS(ReferenceError),
IMPLEMENT_ERROR_CLASS(SyntaxError), IMPLEMENT_ERROR_CLASS(TypeError),
IMPLEMENT_ERROR_CLASS(URIError),
// These Error subclasses are not accessible via the global object:
IMPLEMENT_ERROR_CLASS(DebuggeeWouldRun),
IMPLEMENT_ERROR_CLASS(CompileError), IMPLEMENT_ERROR_CLASS(LinkError),
IMPLEMENT_ERROR_CLASS_MAYBE_WASM_TRAP(RuntimeError)};
static void exn_finalize(JS::GCContext* gcx, JSObject* obj) {
if (JSErrorReport* report = obj->as<ErrorObject>().getErrorReport()) {
gcx->deleteUntracked(report);
}
}
static ErrorObject* CreateErrorObject(JSContext* cx, const CallArgs& args,
unsigned messageArg, JSExnType exnType,
HandleObject proto) {
// Compute the error message, if any.
RootedString message(cx, nullptr);
if (args.hasDefined(messageArg)) {
message = ToString<CanGC>(cx, args[messageArg]);
if (!message) {
return nullptr;
}
}
// Don't interpret the two parameters following the message parameter as the
// non-standard fileName and lineNumber arguments when we have an options
// object argument.
bool hasOptions = args.get(messageArg + 1).isObject();
Rooted<mozilla::Maybe<Value>> cause(cx, mozilla::Nothing());
if (hasOptions) {
RootedObject options(cx, &args[messageArg + 1].toObject());
bool hasCause = false;
if (!HasProperty(cx, options, cx->names().cause, &hasCause)) {
return nullptr;
}
if (hasCause) {
RootedValue causeValue(cx);
if (!GetProperty(cx, options, options, cx->names().cause, &causeValue)) {
return nullptr;
}
cause = mozilla::Some(causeValue.get());
}
}
// Find the scripted caller, but only ones we're allowed to know about.
NonBuiltinFrameIter iter(cx, cx->realm()->principals());
RootedString fileName(cx);
uint32_t sourceId = 0;
if (!hasOptions && args.length() > messageArg + 1) {
fileName = ToString<CanGC>(cx, args[messageArg + 1]);
} else {
fileName = cx->runtime()->emptyString;
if (!iter.done()) {
if (const char* cfilename = iter.filename()) {
fileName = JS_NewStringCopyUTF8Z(
cx, JS::ConstUTF8CharsZ(cfilename, strlen(cfilename)));
}
if (iter.hasScript()) {
sourceId = iter.script()->scriptSource()->id();
}
}
}
if (!fileName) {
return nullptr;
}
uint32_t lineNumber;
JS::ColumnNumberOneOrigin columnNumber;
if (!hasOptions && args.length() > messageArg + 2) {
if (!ToUint32(cx, args[messageArg + 2], &lineNumber)) {
return nullptr;
}
} else {
JS::TaggedColumnNumberOneOrigin tmp;
lineNumber = iter.done() ? 0 : iter.computeLine(&tmp);
columnNumber = JS::ColumnNumberOneOrigin(tmp.oneOriginValue());
}
RootedObject stack(cx);
if (!CaptureStack(cx, &stack)) {
return nullptr;
}
return ErrorObject::create(cx, exnType, stack, fileName, sourceId, lineNumber,
columnNumber, nullptr, message, cause, proto);
}
static bool Error(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// ECMA ed. 3, 15.11.1 requires Error, etc., to construct even when
// called as functions, without operator new. But as we do not give
// each constructor a distinct JSClass, we must get the exception type
// ourselves.
JSExnType exnType =
JSExnType(args.callee().as<JSFunction>().getExtendedSlot(0).toInt32());
MOZ_ASSERT(exnType != JSEXN_AGGREGATEERR,
"AggregateError has its own constructor function");
JSProtoKey protoKey =
JSCLASS_CACHED_PROTO_KEY(&ErrorObject::classes[exnType]);
// ES6 19.5.1.1 mandates the .prototype lookup happens before the toString
RootedObject proto(cx);
if (!GetPrototypeFromBuiltinConstructor(cx, args, protoKey, &proto)) {
return false;
}
auto* obj = CreateErrorObject(cx, args, 0, exnType, proto);
if (!obj) {
return false;
}
args.rval().setObject(*obj);
return true;
}
// AggregateError ( errors, message )
static bool AggregateError(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
mozilla::DebugOnly<JSExnType> exnType =
JSExnType(args.callee().as<JSFunction>().getExtendedSlot(0).toInt32());
MOZ_ASSERT(exnType == JSEXN_AGGREGATEERR);
// Steps 1-2. (9.1.13 OrdinaryCreateFromConstructor, steps 1-2).
RootedObject proto(cx);
if (!GetPrototypeFromBuiltinConstructor(cx, args, JSProto_AggregateError,
&proto)) {
return false;
}
// TypeError anyway, but this gives a better error message.
if (!args.requireAtLeast(cx, "AggregateError", 1)) {
return false;
}
// 9.1.13 OrdinaryCreateFromConstructor, step 3.
// Step 3.
Rooted<ErrorObject*> obj(
cx, CreateErrorObject(cx, args, 1, JSEXN_AGGREGATEERR, proto));
if (!obj) {
return false;
}
// Step 4.
Rooted<ArrayObject*> errorsList(cx);
if (!IterableToArray(cx, args.get(0), &errorsList)) {
return false;
}
// Step 5.
RootedValue errorsVal(cx, JS::ObjectValue(*errorsList));
if (!NativeDefineDataProperty(cx, obj, cx->names().errors, errorsVal, 0)) {
return false;
}
// Step 6.
args.rval().setObject(*obj);
return true;
}
/* static */
JSObject* ErrorObject::createProto(JSContext* cx, JSProtoKey key) {
JSExnType type = ExnTypeFromProtoKey(key);
if (type == JSEXN_ERR) {
return GlobalObject::createBlankPrototype(
cx, cx->global(), &ErrorObject::protoClasses[JSEXN_ERR]);
}
RootedObject protoProto(
cx, GlobalObject::getOrCreateErrorPrototype(cx, cx->global()));
if (!protoProto) {
return nullptr;
}
return GlobalObject::createBlankPrototypeInheriting(
cx, &ErrorObject::protoClasses[type], protoProto);
}
/* static */
JSObject* ErrorObject::createConstructor(JSContext* cx, JSProtoKey key) {
JSExnType type = ExnTypeFromProtoKey(key);
RootedObject ctor(cx);
if (type == JSEXN_ERR) {
ctor = GenericCreateConstructor<Error, 1, gc::AllocKind::FUNCTION_EXTENDED>(
cx, key);
} else {
RootedFunction proto(
cx, GlobalObject::getOrCreateErrorConstructor(cx, cx->global()));
if (!proto) {
return nullptr;
}
Native native;
unsigned nargs;
if (type == JSEXN_AGGREGATEERR) {
native = AggregateError;
nargs = 2;
} else {
native = Error;
nargs = 1;
}
ctor =
NewFunctionWithProto(cx, native, nargs, FunctionFlags::NATIVE_CTOR,
nullptr, ClassName(key, cx), proto,
gc::AllocKind::FUNCTION_EXTENDED, TenuredObject);
}
if (!ctor) {
return nullptr;
}
ctor->as<JSFunction>().setExtendedSlot(0, Int32Value(type));
return ctor;
}
/* static */
SharedShape* js::ErrorObject::assignInitialShape(JSContext* cx,
Handle<ErrorObject*> obj) {
MOZ_ASSERT(obj->empty());
constexpr PropertyFlags propFlags = {PropertyFlag::Configurable,
PropertyFlag::Writable};
if (!NativeObject::addPropertyInReservedSlot(cx, obj, cx->names().fileName,
FILENAME_SLOT, propFlags)) {
return nullptr;
}
if (!NativeObject::addPropertyInReservedSlot(cx, obj, cx->names().lineNumber,
LINENUMBER_SLOT, propFlags)) {
return nullptr;
}
if (!NativeObject::addPropertyInReservedSlot(
cx, obj, cx->names().columnNumber, COLUMNNUMBER_SLOT, propFlags)) {
return nullptr;
}
return obj->sharedShape();
}
/* static */
bool js::ErrorObject::init(JSContext* cx, Handle<ErrorObject*> obj,
JSExnType type, UniquePtr<JSErrorReport> errorReport,
HandleString fileName, HandleObject stack,
uint32_t sourceId, uint32_t lineNumber,
JS::ColumnNumberOneOrigin columnNumber,
HandleString message,
Handle<mozilla::Maybe<JS::Value>> cause) {
MOZ_ASSERT(JSEXN_ERR <= type && type < JSEXN_ERROR_LIMIT);
AssertObjectIsSavedFrameOrWrapper(cx, stack);
cx->check(obj, stack);
// Null out early in case of error, for exn_finalize's sake.
obj->initReservedSlot(ERROR_REPORT_SLOT, PrivateValue(nullptr));
if (!SharedShape::ensureInitialCustomShape<ErrorObject>(cx, obj)) {
return false;
}
// The .message property isn't part of the initial shape because it's
// present in some error objects -- |Error.prototype|, |new Error("f")|,
// |new Error("")| -- but not in others -- |new Error(undefined)|,
// |new Error()|.
if (message) {
constexpr PropertyFlags propFlags = {PropertyFlag::Configurable,
PropertyFlag::Writable};
if (!NativeObject::addPropertyInReservedSlot(cx, obj, cx->names().message,
MESSAGE_SLOT, propFlags)) {
return false;
}
}
// Similar to the .message property, .cause is present only in some error
// objects -- |new Error("f", {cause: cause})| -- but not in other --
// |Error.prototype|, |new Error()|, |new Error("f")|.
if (cause.isSome()) {
constexpr PropertyFlags propFlags = {PropertyFlag::Configurable,
PropertyFlag::Writable};
if (!NativeObject::addPropertyInReservedSlot(cx, obj, cx->names().cause,
CAUSE_SLOT, propFlags)) {
return false;
}
}
MOZ_ASSERT(obj->lookupPure(NameToId(cx->names().fileName))->slot() ==
FILENAME_SLOT);
MOZ_ASSERT(obj->lookupPure(NameToId(cx->names().lineNumber))->slot() ==
LINENUMBER_SLOT);
MOZ_ASSERT(obj->lookupPure(NameToId(cx->names().columnNumber))->slot() ==
COLUMNNUMBER_SLOT);
MOZ_ASSERT_IF(
message,
obj->lookupPure(NameToId(cx->names().message))->slot() == MESSAGE_SLOT);
MOZ_ASSERT_IF(
cause.isSome(),
obj->lookupPure(NameToId(cx->names().cause))->slot() == CAUSE_SLOT);
JSErrorReport* report = errorReport.release();
obj->initReservedSlot(STACK_SLOT, ObjectOrNullValue(stack));
obj->setReservedSlot(ERROR_REPORT_SLOT, PrivateValue(report));
obj->initReservedSlot(FILENAME_SLOT, StringValue(fileName));
obj->initReservedSlot(LINENUMBER_SLOT, Int32Value(lineNumber));
obj->initReservedSlot(COLUMNNUMBER_SLOT,
Int32Value(columnNumber.oneOriginValue()));
if (message) {
obj->initReservedSlot(MESSAGE_SLOT, StringValue(message));
}
if (cause.isSome()) {
obj->initReservedSlot(CAUSE_SLOT, *cause.get());
} else {
obj->initReservedSlot(CAUSE_SLOT, MagicValue(JS_ERROR_WITHOUT_CAUSE));
}
obj->initReservedSlot(SOURCEID_SLOT, Int32Value(sourceId));
if (obj->mightBeWasmTrap()) {
MOZ_ASSERT(JSCLASS_RESERVED_SLOTS(obj->getClass()) > WASM_TRAP_SLOT);
obj->initReservedSlot(WASM_TRAP_SLOT, BooleanValue(false));
}
return true;
}
/* static */
ErrorObject* js::ErrorObject::create(JSContext* cx, JSExnType errorType,
HandleObject stack, HandleString fileName,
uint32_t sourceId, uint32_t lineNumber,
JS::ColumnNumberOneOrigin columnNumber,
UniquePtr<JSErrorReport> report,
HandleString message,
Handle<mozilla::Maybe<JS::Value>> cause,
HandleObject protoArg /* = nullptr */) {
AssertObjectIsSavedFrameOrWrapper(cx, stack);
RootedObject proto(cx, protoArg);
if (!proto) {
proto = GlobalObject::getOrCreateCustomErrorPrototype(cx, cx->global(),
errorType);
if (!proto) {
return nullptr;
}
}
Rooted<ErrorObject*> errObject(cx);
{
const JSClass* clasp = ErrorObject::classForType(errorType);
JSObject* obj = NewObjectWithGivenProto(cx, clasp, proto);
if (!obj) {
return nullptr;
}
errObject = &obj->as<ErrorObject>();
}
if (!ErrorObject::init(cx, errObject, errorType, std::move(report), fileName,
stack, sourceId, lineNumber, columnNumber, message,
cause)) {
return nullptr;
}
return errObject;
}
JSErrorReport* js::ErrorObject::getOrCreateErrorReport(JSContext* cx) {
if (JSErrorReport* r = getErrorReport()) {
return r;
}
// We build an error report on the stack and then use CopyErrorReport to do
// the nitty-gritty malloc stuff.
JSErrorReport report;
// Type.
JSExnType type_ = type();
report.exnType = type_;
// Filename.
RootedString filename(cx, fileName(cx));
UniqueChars filenameStr = JS_EncodeStringToUTF8(cx, filename);
if (!filenameStr) {
return nullptr;
}
report.filename = JS::ConstUTF8CharsZ(filenameStr.get());
// Coordinates.
report.sourceId = sourceId();
report.lineno = lineNumber();
report.column = columnNumber();
// Message. Note that |new Error()| will result in an undefined |message|
// slot, so we need to explicitly substitute the empty string in that case.
RootedString message(cx, getMessage());
if (!message) {
message = cx->runtime()->emptyString;
}
UniqueChars utf8 = StringToNewUTF8CharsZ(cx, *message);
if (!utf8) {
return nullptr;
}
report.initOwnedMessage(utf8.release());
// Cache and return.
UniquePtr<JSErrorReport> copy = CopyErrorReport(cx, &report);
if (!copy) {
return nullptr;
}
setReservedSlot(ERROR_REPORT_SLOT, PrivateValue(copy.get()));
return copy.release();
}
static bool FindErrorInstanceOrPrototype(JSContext* cx, HandleObject obj,
MutableHandleObject result) {
// Walk up the prototype chain until we find an error object instance or
// prototype object. This allows code like:
// Object.create(Error.prototype).stack
// or
// function NYI() { }
// NYI.prototype = new Error;
// (new NYI).stack
// to continue returning stacks that are useless, but at least don't throw.
RootedObject curr(cx, obj);
RootedObject target(cx);
do {
target = CheckedUnwrapStatic(curr);
if (!target) {
ReportAccessDenied(cx);
return false;
}
if (IsErrorProtoKey(StandardProtoKeyOrNull(target))) {
result.set(target);
return true;
}
if (!GetPrototype(cx, curr, &curr)) {
return false;
}
} while (curr);
// We walked the whole prototype chain and did not find an Error
// object.
JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
JSMSG_INCOMPATIBLE_PROTO, "Error", "(get stack)",
obj->getClass()->name);
return false;
}
static MOZ_ALWAYS_INLINE bool IsObject(HandleValue v) { return v.isObject(); }
/* static */
bool js::ErrorObject::getStack(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// We accept any object here, because of poor-man's subclassing of Error.
return CallNonGenericMethod<IsObject, getStack_impl>(cx, args);
}
/* static */
bool js::ErrorObject::getStack_impl(JSContext* cx, const CallArgs& args) {
RootedObject thisObj(cx, &args.thisv().toObject());
RootedObject obj(cx);
if (!FindErrorInstanceOrPrototype(cx, thisObj, &obj)) {
return false;
}
if (!obj->is<ErrorObject>()) {
args.rval().setString(cx->runtime()->emptyString);
return true;
}
// Do frame filtering based on the ErrorObject's principals. This ensures we
// don't see chrome frames when chrome code accesses .stack over Xrays.
JSPrincipals* principals = obj->as<ErrorObject>().realm()->principals();
RootedObject savedFrameObj(cx, obj->as<ErrorObject>().stack());
RootedString stackString(cx);
if (!BuildStackString(cx, principals, savedFrameObj, &stackString)) {
return false;
}
if (cx->runtime()->stackFormat() == js::StackFormat::V8) {
// When emulating V8 stack frames, we also need to prepend the
// stringified Error to the stack string.
Handle<PropertyName*> name = cx->names().ErrorToStringWithTrailingNewline;
FixedInvokeArgs<0> args2(cx);
RootedValue rval(cx);
if (!CallSelfHostedFunction(cx, name, args.thisv(), args2, &rval)) {
return false;
}
if (!rval.isString()) {
args.rval().setString(cx->runtime()->emptyString);
return true;
}
RootedString stringified(cx, rval.toString());
stackString = ConcatStrings<CanGC>(cx, stringified, stackString);
}
args.rval().setString(stackString);
return true;
}
/* static */
bool js::ErrorObject::setStack(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// We accept any object here, because of poor-man's subclassing of Error.
return CallNonGenericMethod<IsObject, setStack_impl>(cx, args);
}
/* static */
bool js::ErrorObject::setStack_impl(JSContext* cx, const CallArgs& args) {
RootedObject thisObj(cx, &args.thisv().toObject());
if (!args.requireAtLeast(cx, "(set stack)", 1)) {
return false;
}
RootedValue val(cx, args[0]);
return DefineDataProperty(cx, thisObj, cx->names().stack, val);
}
void js::ErrorObject::setFromWasmTrap() {
MOZ_ASSERT(mightBeWasmTrap());
MOZ_ASSERT(JSCLASS_RESERVED_SLOTS(getClass()) > WASM_TRAP_SLOT);
setReservedSlot(WASM_TRAP_SLOT, BooleanValue(true));
}
JSString* js::ErrorToSource(JSContext* cx, HandleObject obj) {
RootedValue nameVal(cx);
RootedString name(cx);
if (!GetProperty(cx, obj, obj, cx->names().name, &nameVal) ||
!(name = ToString<CanGC>(cx, nameVal))) {
return nullptr;
}
RootedValue messageVal(cx);
RootedString message(cx);
if (!GetProperty(cx, obj, obj, cx->names().message, &messageVal) ||
!(message = ValueToSource(cx, messageVal))) {
return nullptr;
}
RootedValue filenameVal(cx);
RootedString filename(cx);
if (!GetProperty(cx, obj, obj, cx->names().fileName, &filenameVal) ||
!(filename = ValueToSource(cx, filenameVal))) {
return nullptr;
}
RootedValue linenoVal(cx);
uint32_t lineno;
if (!GetProperty(cx, obj, obj, cx->names().lineNumber, &linenoVal) ||
!ToUint32(cx, linenoVal, &lineno)) {
return nullptr;
}
JSStringBuilder sb(cx);
if (!sb.append("(new ") || !sb.append(name) || !sb.append("(")) {
return nullptr;
}
if (!sb.append(message)) {
return nullptr;
}
if (!filename->empty()) {
if (!sb.append(", ") || !sb.append(filename)) {
return nullptr;
}
}
if (lineno != 0) {
/* We have a line, but no filename, add empty string */
if (filename->empty() && !sb.append(", \"\"")) {
return nullptr;
}
JSString* linenumber = ToString<CanGC>(cx, linenoVal);
if (!linenumber) {
return nullptr;
}
if (!sb.append(", ") || !sb.append(linenumber)) {
return nullptr;
}
}
if (!sb.append("))")) {
return nullptr;
}
return sb.finishString();
}
/*
* Return a string that may eval to something similar to the original object.
*/
static bool exn_toSource(JSContext* cx, unsigned argc, Value* vp) {
AutoCheckRecursionLimit recursion(cx);
if (!recursion.check(cx)) {
return false;
}
CallArgs args = CallArgsFromVp(argc, vp);
RootedObject obj(cx, ToObject(cx, args.thisv()));
if (!obj) {
return false;
}
JSString* str = ErrorToSource(cx, obj);
if (!str) {
return false;
}
args.rval().setString(str);
return true;
}