https://github.com/mozilla/gecko-dev
Tip revision: 52568d10660dfb0ce950f6983b20228374602efe authored by Nick Thomas on 14 November 2019, 03:15:51 UTC
Bug 1595632 - don't hardcode TC root url for release start emails, r=Callek a=NPOTB
Bug 1595632 - don't hardcode TC root url for release start emails, r=Callek a=NPOTB
Tip revision: 52568d1
jsexn.cpp
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: set ts=8 sts=2 et sw=2 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
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/*
* JS standard exception implementation.
*/
#include "jsexn.h"
#include "mozilla/ScopeExit.h"
#include "mozilla/Sprintf.h"
#include <string.h>
#include <utility>
#include "jsapi.h"
#include "jsnum.h"
#include "jstypes.h"
#include "jsutil.h"
#include "gc/FreeOp.h"
#include "gc/Marking.h"
#include "js/CharacterEncoding.h"
#include "js/PropertySpec.h"
#include "js/UniquePtr.h"
#include "js/Warnings.h" // JS::{,Set}WarningReporter
#include "js/Wrapper.h"
#include "util/StringBuffer.h"
#include "vm/ErrorObject.h"
#include "vm/GlobalObject.h"
#include "vm/JSContext.h"
#include "vm/JSFunction.h"
#include "vm/JSObject.h"
#include "vm/JSScript.h"
#include "vm/SavedStacks.h"
#include "vm/SelfHosting.h"
#include "vm/StringType.h"
#include "vm/ErrorObject-inl.h"
#include "vm/JSObject-inl.h"
#include "vm/SavedStacks-inl.h"
using namespace js;
static void exn_finalize(FreeOp* fop, JSObject* obj);
static bool exn_toSource(JSContext* cx, unsigned argc, Value* vp);
#define IMPLEMENT_ERROR_PROTO_CLASS(name) \
{ \
js_Object_str, JSCLASS_HAS_CACHED_PROTO(JSProto_##name), \
JS_NULL_CLASS_OPS, \
&ErrorObject::classSpecs[JSProto_##name - JSProto_Error] \
}
const Class ErrorObject::protoClasses[JSEXN_ERROR_LIMIT] = {
IMPLEMENT_ERROR_PROTO_CLASS(Error),
IMPLEMENT_ERROR_PROTO_CLASS(InternalError),
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 const JSFunctionSpec error_methods[] = {
JS_FN(js_toSource_str, exn_toSource, 0, 0),
JS_SELF_HOSTED_FN(js_toString_str, "ErrorToString", 0, 0), JS_FS_END};
static const JSPropertySpec error_properties[] = {
JS_STRING_PS("message", "", 0), JS_STRING_PS("name", "Error", 0),
// Only Error.prototype has .stack!
JS_PSGS("stack", ErrorObject::getStack, ErrorObject::setStack, 0),
JS_PS_END};
#define IMPLEMENT_ERROR_PROPERTIES(name) \
{ JS_STRING_PS("message", "", 0), JS_STRING_PS("name", #name, 0), JS_PS_END }
static const JSPropertySpec other_error_properties[JSEXN_ERROR_LIMIT - 1][3] = {
IMPLEMENT_ERROR_PROPERTIES(InternalError),
IMPLEMENT_ERROR_PROPERTIES(EvalError),
IMPLEMENT_ERROR_PROPERTIES(RangeError),
IMPLEMENT_ERROR_PROPERTIES(ReferenceError),
IMPLEMENT_ERROR_PROPERTIES(SyntaxError),
IMPLEMENT_ERROR_PROPERTIES(TypeError),
IMPLEMENT_ERROR_PROPERTIES(URIError),
IMPLEMENT_ERROR_PROPERTIES(DebuggeeWouldRun),
IMPLEMENT_ERROR_PROPERTIES(CompileError),
IMPLEMENT_ERROR_PROPERTIES(LinkError),
IMPLEMENT_ERROR_PROPERTIES(RuntimeError)};
#define IMPLEMENT_NATIVE_ERROR_SPEC(name) \
{ \
ErrorObject::createConstructor, ErrorObject::createProto, nullptr, \
nullptr, nullptr, \
other_error_properties[JSProto_##name - JSProto_Error - 1], nullptr, \
JSProto_Error \
}
#define IMPLEMENT_NONGLOBAL_ERROR_SPEC(name) \
{ \
ErrorObject::createConstructor, ErrorObject::createProto, nullptr, \
nullptr, nullptr, \
other_error_properties[JSProto_##name - JSProto_Error - 1], 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(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(name) \
{ \
js_Error_str, /* yes, really */ \
JSCLASS_HAS_CACHED_PROTO(JSProto_##name) | \
JSCLASS_HAS_RESERVED_SLOTS(ErrorObject::RESERVED_SLOTS) | \
JSCLASS_BACKGROUND_FINALIZE, \
&ErrorObjectClassOps, \
&ErrorObject::classSpecs[JSProto_##name - JSProto_Error] \
}
static const ClassOps ErrorObjectClassOps = {
nullptr, /* addProperty */
nullptr, /* delProperty */
nullptr, /* enumerate */
nullptr, /* newEnumerate */
nullptr, /* resolve */
nullptr, /* mayResolve */
exn_finalize, nullptr, /* call */
nullptr, /* hasInstance */
nullptr, /* construct */
nullptr, /* trace */
};
const Class ErrorObject::classes[JSEXN_ERROR_LIMIT] = {
IMPLEMENT_ERROR_CLASS(Error), IMPLEMENT_ERROR_CLASS(InternalError),
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(RuntimeError)};
size_t ExtraMallocSize(JSErrorReport* report) {
if (report->linebuf()) {
/*
* Count with null terminator and alignment.
* See CopyExtraData for the details about alignment.
*/
return (report->linebufLength() + 1) * sizeof(char16_t) + 1;
}
return 0;
}
size_t ExtraMallocSize(JSErrorNotes::Note* note) { return 0; }
bool CopyExtraData(JSContext* cx, uint8_t** cursor, JSErrorReport* copy,
JSErrorReport* report) {
if (report->linebuf()) {
/*
* Make sure cursor is properly aligned for char16_t for platforms
* which need it and it's at the end of the buffer on exit.
*/
size_t alignment_backlog = 0;
if (size_t(*cursor) % 2) {
(*cursor)++;
} else {
alignment_backlog = 1;
}
size_t linebufSize = (report->linebufLength() + 1) * sizeof(char16_t);
const char16_t* linebufCopy = (const char16_t*)(*cursor);
js_memcpy(*cursor, report->linebuf(), linebufSize);
*cursor += linebufSize + alignment_backlog;
copy->initBorrowedLinebuf(linebufCopy, report->linebufLength(),
report->tokenOffset());
}
/* Copy non-pointer members. */
copy->isMuted = report->isMuted;
copy->exnType = report->exnType;
/* Note that this is before it gets flagged with JSREPORT_EXCEPTION */
copy->flags = report->flags;
/* Deep copy notes. */
if (report->notes) {
auto copiedNotes = report->notes->copy(cx);
if (!copiedNotes) {
return false;
}
copy->notes = std::move(copiedNotes);
} else {
copy->notes.reset(nullptr);
}
return true;
}
bool CopyExtraData(JSContext* cx, uint8_t** cursor, JSErrorNotes::Note* copy,
JSErrorNotes::Note* report) {
return true;
}
template <typename T>
static UniquePtr<T> CopyErrorHelper(JSContext* cx, T* report) {
/*
* We use a single malloc block to make a deep copy of JSErrorReport or
* JSErrorNotes::Note, except JSErrorNotes linked from JSErrorReport with
* the following layout:
* JSErrorReport or JSErrorNotes::Note
* char array with characters for message_
* char array with characters for filename
* char16_t array with characters for linebuf (only for JSErrorReport)
* Such layout together with the properties enforced by the following
* asserts does not need any extra alignment padding.
*/
JS_STATIC_ASSERT(sizeof(T) % sizeof(const char*) == 0);
JS_STATIC_ASSERT(sizeof(const char*) % sizeof(char16_t) == 0);
size_t filenameSize = report->filename ? strlen(report->filename) + 1 : 0;
size_t messageSize = 0;
if (report->message()) {
messageSize = strlen(report->message().c_str()) + 1;
}
/*
* The mallocSize can not overflow since it represents the sum of the
* sizes of already allocated objects.
*/
size_t mallocSize =
sizeof(T) + messageSize + filenameSize + ExtraMallocSize(report);
uint8_t* cursor = cx->pod_calloc<uint8_t>(mallocSize);
if (!cursor) {
return nullptr;
}
UniquePtr<T> copy(new (cursor) T());
cursor += sizeof(T);
if (report->message()) {
copy->initBorrowedMessage((const char*)cursor);
js_memcpy(cursor, report->message().c_str(), messageSize);
cursor += messageSize;
}
if (report->filename) {
copy->filename = (const char*)cursor;
js_memcpy(cursor, report->filename, filenameSize);
cursor += filenameSize;
}
if (!CopyExtraData(cx, &cursor, copy.get(), report)) {
return nullptr;
}
MOZ_ASSERT(cursor == (uint8_t*)copy.get() + mallocSize);
/* Copy non-pointer members. */
copy->sourceId = report->sourceId;
copy->lineno = report->lineno;
copy->column = report->column;
copy->errorNumber = report->errorNumber;
return copy;
}
UniquePtr<JSErrorNotes::Note> js::CopyErrorNote(JSContext* cx,
JSErrorNotes::Note* note) {
return CopyErrorHelper(cx, note);
}
UniquePtr<JSErrorReport> js::CopyErrorReport(JSContext* cx,
JSErrorReport* report) {
return CopyErrorHelper(cx, report);
}
struct SuppressErrorsGuard {
JSContext* cx;
JS::WarningReporter prevReporter;
JS::AutoSaveExceptionState prevState;
explicit SuppressErrorsGuard(JSContext* cx)
: cx(cx),
prevReporter(JS::SetWarningReporter(cx, nullptr)),
prevState(cx) {}
~SuppressErrorsGuard() { JS::SetWarningReporter(cx, prevReporter); }
};
// Cut off the stack if it gets too deep (most commonly for infinite recursion
// errors).
static const size_t MAX_REPORTED_STACK_DEPTH = 1u << 7;
static bool CaptureStack(JSContext* cx, MutableHandleObject stack) {
return CaptureCurrentStack(
cx, stack, JS::StackCapture(JS::MaxFrames(MAX_REPORTED_STACK_DEPTH)));
}
JSString* js::ComputeStackString(JSContext* cx) {
SuppressErrorsGuard seg(cx);
RootedObject stack(cx);
if (!CaptureStack(cx, &stack)) {
return nullptr;
}
RootedString str(cx);
if (!BuildStackString(cx, cx->realm()->principals(), stack, &str)) {
return nullptr;
}
return str.get();
}
static void exn_finalize(FreeOp* fop, JSObject* obj) {
MOZ_ASSERT(fop->maybeOnHelperThread());
if (JSErrorReport* report = obj->as<ErrorObject>().getErrorReport()) {
fop->delete_(report);
}
}
JSErrorReport* js::ErrorFromException(JSContext* cx, HandleObject objArg) {
// It's ok to UncheckedUnwrap here, since all we do is get the
// JSErrorReport, and consumers are careful with the information they get
// from that anyway. Anyone doing things that would expose anything in the
// JSErrorReport to page script either does a security check on the
// JSErrorReport's principal or also tries to do toString on our object and
// will fail if they can't unwrap it.
RootedObject obj(cx, UncheckedUnwrap(objArg));
if (!obj->is<ErrorObject>()) {
return nullptr;
}
JSErrorReport* report = obj->as<ErrorObject>().getOrCreateErrorReport(cx);
if (!report) {
MOZ_ASSERT(cx->isThrowingOutOfMemory());
cx->recoverFromOutOfMemory();
}
return report;
}
JS_PUBLIC_API JSObject* JS::ExceptionStackOrNull(HandleObject objArg) {
ErrorObject* obj = objArg->maybeUnwrapIf<ErrorObject>();
if (!obj) {
return nullptr;
}
return obj->stack();
}
JS_PUBLIC_API uint64_t JS::ExceptionTimeWarpTarget(JS::HandleValue value) {
if (!value.isObject()) {
return 0;
}
ErrorObject* obj = value.toObject().maybeUnwrapIf<ErrorObject>();
if (!obj) {
return 0;
}
return obj->timeWarpTarget();
}
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());
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;
}
// Compute the error message, if any.
RootedString message(cx, nullptr);
if (args.hasDefined(0)) {
message = ToString<CanGC>(cx, args[0]);
if (!message) {
return false;
}
}
// 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 (args.length() > 1) {
fileName = ToString<CanGC>(cx, args[1]);
} else {
fileName = cx->runtime()->emptyString;
if (!iter.done()) {
if (const char* cfilename = iter.filename()) {
fileName = JS_NewStringCopyZ(cx, cfilename);
}
if (iter.hasScript()) {
sourceId = iter.script()->scriptSource()->id();
}
}
}
if (!fileName) {
return false;
}
uint32_t lineNumber, columnNumber = 0;
if (args.length() > 2) {
if (!ToUint32(cx, args[2], &lineNumber)) {
return false;
}
} else {
lineNumber = iter.done() ? 0 : iter.computeLine(&columnNumber);
columnNumber = FixupColumnForDisplay(columnNumber);
}
RootedObject stack(cx);
if (!CaptureStack(cx, &stack)) {
return false;
}
RootedObject obj(cx, ErrorObject::create(cx, exnType, stack, fileName,
sourceId, lineNumber, columnNumber,
nullptr, message, proto));
if (!obj) {
return false;
}
args.rval().setObject(*obj);
return true;
}
/*
* Return a string that may eval to something similar to the original object.
*/
static bool exn_toSource(JSContext* cx, unsigned argc, Value* vp) {
if (!CheckRecursionLimit(cx)) {
return false;
}
CallArgs args = CallArgsFromVp(argc, vp);
RootedObject obj(cx, ToObject(cx, args.thisv()));
if (!obj) {
return false;
}
RootedValue nameVal(cx);
RootedString name(cx);
if (!GetProperty(cx, obj, obj, cx->names().name, &nameVal) ||
!(name = ToString<CanGC>(cx, nameVal))) {
return false;
}
RootedValue messageVal(cx);
RootedString message(cx);
if (!GetProperty(cx, obj, obj, cx->names().message, &messageVal) ||
!(message = ValueToSource(cx, messageVal))) {
return false;
}
RootedValue filenameVal(cx);
RootedString filename(cx);
if (!GetProperty(cx, obj, obj, cx->names().fileName, &filenameVal) ||
!(filename = ValueToSource(cx, filenameVal))) {
return false;
}
RootedValue linenoVal(cx);
uint32_t lineno;
if (!GetProperty(cx, obj, obj, cx->names().lineNumber, &linenoVal) ||
!ToUint32(cx, linenoVal, &lineno)) {
return false;
}
JSStringBuilder sb(cx);
if (!sb.append("(new ") || !sb.append(name) || !sb.append("(")) {
return false;
}
if (!sb.append(message)) {
return false;
}
if (!filename->empty()) {
if (!sb.append(", ") || !sb.append(filename)) {
return false;
}
}
if (lineno != 0) {
/* We have a line, but no filename, add empty string */
if (filename->empty() && !sb.append(", \"\"")) {
return false;
}
JSString* linenumber = ToString<CanGC>(cx, linenoVal);
if (!linenumber) {
return false;
}
if (!sb.append(", ") || !sb.append(linenumber)) {
return false;
}
}
if (!sb.append("))")) {
return false;
}
JSString* str = sb.finishString();
if (!str) {
return false;
}
args.rval().setString(str);
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;
}
ctor = NewFunctionWithProto(
cx, Error, 1, JSFunction::NATIVE_CTOR, nullptr, ClassName(key, cx),
proto, gc::AllocKind::FUNCTION_EXTENDED, SingletonObject);
}
if (!ctor) {
return nullptr;
}
ctor->as<JSFunction>().setExtendedSlot(0, Int32Value(type));
return ctor;
}
JS_FRIEND_API JSFlatString* js::GetErrorTypeName(JSContext* cx,
int16_t exnType) {
/*
* JSEXN_INTERNALERR returns null to prevent that "InternalError: "
* is prepended before "uncaught exception: "
*/
if (exnType < 0 || exnType >= JSEXN_LIMIT || exnType == JSEXN_INTERNALERR ||
exnType == JSEXN_WARN || exnType == JSEXN_NOTE) {
return nullptr;
}
JSProtoKey key = GetExceptionProtoKey(JSExnType(exnType));
return ClassName(key, cx);
}
void js::ErrorToException(JSContext* cx, JSErrorReport* reportp,
JSErrorCallback callback, void* userRef) {
MOZ_ASSERT(reportp);
MOZ_ASSERT(!JSREPORT_IS_WARNING(reportp->flags));
// We cannot throw a proper object inside the self-hosting realm, as we
// cannot construct the Error constructor without self-hosted code. Just
// print the error to stderr to help debugging.
if (cx->realm()->isSelfHostingRealm()) {
PrintError(cx, stderr, JS::ConstUTF8CharsZ(), reportp, true);
return;
}
// Find the exception index associated with this error.
JSErrNum errorNumber = static_cast<JSErrNum>(reportp->errorNumber);
if (!callback) {
callback = GetErrorMessage;
}
const JSErrorFormatString* errorString = callback(userRef, errorNumber);
JSExnType exnType =
errorString ? static_cast<JSExnType>(errorString->exnType) : JSEXN_ERR;
MOZ_ASSERT(exnType < JSEXN_LIMIT);
MOZ_ASSERT(exnType != JSEXN_NOTE);
if (exnType == JSEXN_WARN) {
// werror must be enabled, so we use JSEXN_ERR.
MOZ_ASSERT(cx->options().werror());
exnType = JSEXN_ERR;
}
// Prevent infinite recursion.
if (cx->generatingError) {
return;
}
cx->generatingError = true;
auto restore = mozilla::MakeScopeExit([cx] { cx->generatingError = false; });
// Create an exception object.
RootedString messageStr(cx, reportp->newMessageString(cx));
if (!messageStr) {
return;
}
RootedString fileName(cx, JS_NewStringCopyZ(cx, reportp->filename));
if (!fileName) {
return;
}
uint32_t sourceId = reportp->sourceId;
uint32_t lineNumber = reportp->lineno;
uint32_t columnNumber = reportp->column;
RootedObject stack(cx);
if (!CaptureStack(cx, &stack)) {
return;
}
UniquePtr<JSErrorReport> report = CopyErrorReport(cx, reportp);
if (!report) {
return;
}
ErrorObject* errObject =
ErrorObject::create(cx, exnType, stack, fileName, sourceId, lineNumber,
columnNumber, std::move(report), messageStr);
if (!errObject) {
return;
}
// Throw it.
RootedValue errValue(cx, ObjectValue(*errObject));
RootedSavedFrame nstack(cx);
if (stack) {
nstack = &stack->as<SavedFrame>();
}
cx->setPendingException(errValue, nstack);
// Flag the error report passed in to indicate an exception was raised.
reportp->flags |= JSREPORT_EXCEPTION;
}
static bool IsDuckTypedErrorObject(JSContext* cx, HandleObject exnObject,
const char** filename_strp) {
/*
* This function is called from ErrorReport::init and so should not generate
* any new exceptions.
*/
AutoClearPendingException acpe(cx);
bool found;
if (!JS_HasProperty(cx, exnObject, js_message_str, &found) || !found) {
return false;
}
// First try "filename".
const char* filename_str = *filename_strp;
if (!JS_HasProperty(cx, exnObject, filename_str, &found)) {
return false;
}
if (!found) {
// If that doesn't work, try "fileName".
filename_str = js_fileName_str;
if (!JS_HasProperty(cx, exnObject, filename_str, &found) || !found) {
return false;
}
}
if (!JS_HasProperty(cx, exnObject, js_lineNumber_str, &found) || !found) {
return false;
}
*filename_strp = filename_str;
return true;
}
static JSString* ErrorReportToString(JSContext* cx, JSErrorReport* reportp) {
/*
* We do NOT want to use GetErrorTypeName() here because it will not do the
* "right thing" for JSEXN_INTERNALERR. That is, the caller of this API
* expects that "InternalError: " will be prepended but GetErrorTypeName
* goes out of its way to avoid this.
*/
JSExnType type = static_cast<JSExnType>(reportp->exnType);
RootedString str(cx);
if (type != JSEXN_WARN && type != JSEXN_NOTE) {
str = ClassName(GetExceptionProtoKey(type), cx);
}
/*
* If "str" is null at this point, that means we just want to use
* message without prefixing it with anything.
*/
if (str) {
RootedString separator(cx, JS_NewUCStringCopyN(cx, u": ", 2));
if (!separator) {
return nullptr;
}
str = ConcatStrings<CanGC>(cx, str, separator);
if (!str) {
return nullptr;
}
}
RootedString message(cx, reportp->newMessageString(cx));
if (!message) {
return nullptr;
}
if (!str) {
return message;
}
return ConcatStrings<CanGC>(cx, str, message);
}
ErrorReport::ErrorReport(JSContext* cx)
: reportp(nullptr), str(cx), strChars(cx), exnObject(cx) {}
ErrorReport::~ErrorReport() {}
bool ErrorReport::init(JSContext* cx, HandleValue exn,
SniffingBehavior sniffingBehavior) {
MOZ_ASSERT(!cx->isExceptionPending());
MOZ_ASSERT(!reportp);
if (exn.isObject()) {
// Because ToString below could error and an exception object could become
// unrooted, we must root our exception object, if any.
exnObject = &exn.toObject();
reportp = ErrorFromException(cx, exnObject);
if (!reportp && sniffingBehavior == NoSideEffects) {
JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
JSMSG_ERR_DURING_THROW);
return false;
}
}
// Be careful not to invoke ToString if we've already successfully extracted
// an error report, since the exception might be wrapped in a security
// wrapper, and ToString-ing it might throw.
if (reportp) {
str = ErrorReportToString(cx, reportp);
} else if (exn.isSymbol()) {
RootedValue strVal(cx);
if (js::SymbolDescriptiveString(cx, exn.toSymbol(), &strVal)) {
str = strVal.toString();
} else {
str = nullptr;
}
} else {
str = ToString<CanGC>(cx, exn);
}
if (!str) {
cx->clearPendingException();
}
// If ErrorFromException didn't get us a JSErrorReport, then the object
// was not an ErrorObject, security-wrapped or otherwise. However, it might
// still quack like one. Give duck-typing a chance. We start by looking for
// "filename" (all lowercase), since that's where DOMExceptions store their
// filename. Then we check "fileName", which is where Errors store it. We
// have to do it in that order, because DOMExceptions have Error.prototype
// on their proto chain, and hence also have a "fileName" property, but its
// value is "".
const char* filename_str = "filename";
if (!reportp && exnObject &&
IsDuckTypedErrorObject(cx, exnObject, &filename_str)) {
// Temporary value for pulling properties off of duck-typed objects.
RootedValue val(cx);
RootedString name(cx);
if (JS_GetProperty(cx, exnObject, js_name_str, &val) && val.isString()) {
name = val.toString();
} else {
cx->clearPendingException();
}
RootedString msg(cx);
if (JS_GetProperty(cx, exnObject, js_message_str, &val) && val.isString()) {
msg = val.toString();
} else {
cx->clearPendingException();
}
// If we have the right fields, override the ToString we performed on
// the exception object above with something built out of its quacks
// (i.e. as much of |NameQuack: MessageQuack| as we can make).
//
// It would be nice to use ErrorReportToString here, but we can't quite
// do it - mostly because we'd need to figure out what JSExnType |name|
// corresponds to, which may not be any JSExnType at all.
if (name && msg) {
RootedString colon(cx, JS_NewStringCopyZ(cx, ": "));
if (!colon) {
return false;
}
RootedString nameColon(cx, ConcatStrings<CanGC>(cx, name, colon));
if (!nameColon) {
return false;
}
str = ConcatStrings<CanGC>(cx, nameColon, msg);
if (!str) {
return false;
}
} else if (name) {
str = name;
} else if (msg) {
str = msg;
}
if (JS_GetProperty(cx, exnObject, filename_str, &val)) {
RootedString tmp(cx, ToString<CanGC>(cx, val));
if (tmp) {
filename = JS_EncodeStringToUTF8(cx, tmp);
} else {
cx->clearPendingException();
}
} else {
cx->clearPendingException();
}
uint32_t lineno;
if (!JS_GetProperty(cx, exnObject, js_lineNumber_str, &val) ||
!ToUint32(cx, val, &lineno)) {
cx->clearPendingException();
lineno = 0;
}
uint32_t column;
if (!JS_GetProperty(cx, exnObject, js_columnNumber_str, &val) ||
!ToUint32(cx, val, &column)) {
cx->clearPendingException();
column = 0;
}
reportp = &ownedReport;
new (reportp) JSErrorReport();
ownedReport.filename = filename.get();
ownedReport.lineno = lineno;
ownedReport.exnType = JSEXN_INTERNALERR;
ownedReport.column = column;
if (str) {
// Note that using |str| for |message_| here is kind of wrong,
// because |str| is supposed to be of the format
// |ErrorName: ErrorMessage|, and |message_| is supposed to
// correspond to |ErrorMessage|. But this is what we've
// historically done for duck-typed error objects.
//
// If only this stuff could get specced one day...
char* utf8;
if (str->ensureFlat(cx) && strChars.initTwoByte(cx, str) &&
(utf8 =
JS::CharsToNewUTF8CharsZ(cx, strChars.twoByteRange()).c_str())) {
ownedReport.initOwnedMessage(utf8);
} else {
cx->clearPendingException();
str = nullptr;
}
}
}
const char* utf8Message = nullptr;
if (str) {
toStringResultBytesStorage = JS_EncodeStringToUTF8(cx, str);
utf8Message = toStringResultBytesStorage.get();
}
if (!utf8Message) {
utf8Message = "unknown (can't convert to string)";
}
if (!reportp) {
// This is basically an inlined version of
//
// JS_ReportErrorNumberUTF8(cx, GetErrorMessage, nullptr,
// JSMSG_UNCAUGHT_EXCEPTION, utf8Message);
//
// but without the reporting bits. Instead it just puts all
// the stuff we care about in our ownedReport and message_.
if (!populateUncaughtExceptionReportUTF8(cx, utf8Message)) {
// Just give up. We're out of memory or something; not much we can
// do here.
return false;
}
} else {
toStringResult_ = JS::ConstUTF8CharsZ(utf8Message, strlen(utf8Message));
/* Flag the error as an exception. */
reportp->flags |= JSREPORT_EXCEPTION;
}
return true;
}
bool ErrorReport::populateUncaughtExceptionReportUTF8(JSContext* cx, ...) {
va_list ap;
va_start(ap, cx);
bool ok = populateUncaughtExceptionReportUTF8VA(cx, ap);
va_end(ap);
return ok;
}
bool ErrorReport::populateUncaughtExceptionReportUTF8VA(JSContext* cx,
va_list ap) {
new (&ownedReport) JSErrorReport();
ownedReport.flags = JSREPORT_ERROR;
ownedReport.errorNumber = JSMSG_UNCAUGHT_EXCEPTION;
// XXXbz this assumes the stack we have right now is still
// related to our exception object. It would be better if we
// could accept a passed-in stack of some sort instead.
NonBuiltinFrameIter iter(cx, cx->realm()->principals());
if (!iter.done()) {
ownedReport.filename = iter.filename();
uint32_t column;
ownedReport.sourceId =
iter.hasScript() ? iter.script()->scriptSource()->id() : 0;
ownedReport.lineno = iter.computeLine(&column);
ownedReport.column = FixupColumnForDisplay(column);
ownedReport.isMuted = iter.mutedErrors();
}
if (!ExpandErrorArgumentsVA(cx, GetErrorMessage, nullptr,
JSMSG_UNCAUGHT_EXCEPTION, nullptr,
ArgumentsAreUTF8, &ownedReport, ap)) {
return false;
}
toStringResult_ = ownedReport.message();
reportp = &ownedReport;
return true;
}
JSObject* js::CopyErrorObject(JSContext* cx, Handle<ErrorObject*> err) {
UniquePtr<JSErrorReport> copyReport;
if (JSErrorReport* errorReport = err->getErrorReport()) {
copyReport = CopyErrorReport(cx, errorReport);
if (!copyReport) {
return nullptr;
}
}
RootedString message(cx, err->getMessage());
if (message && !cx->compartment()->wrap(cx, &message)) {
return nullptr;
}
RootedString fileName(cx, err->fileName(cx));
if (!cx->compartment()->wrap(cx, &fileName)) {
return nullptr;
}
RootedObject stack(cx, err->stack());
if (!cx->compartment()->wrap(cx, &stack)) {
return nullptr;
}
uint32_t sourceId = err->sourceId();
uint32_t lineNumber = err->lineNumber();
uint32_t columnNumber = err->columnNumber();
JSExnType errorType = err->type();
// Create the Error object.
return ErrorObject::create(cx, errorType, stack, fileName, sourceId,
lineNumber, columnNumber, std::move(copyReport),
message);
}
JS_PUBLIC_API bool JS::CreateError(JSContext* cx, JSExnType type,
HandleObject stack, HandleString fileName,
uint32_t lineNumber, uint32_t columnNumber,
JSErrorReport* report, HandleString message,
MutableHandleValue rval) {
cx->check(stack, fileName, message);
AssertObjectIsSavedFrameOrWrapper(cx, stack);
js::UniquePtr<JSErrorReport> rep;
if (report) {
rep = CopyErrorReport(cx, report);
if (!rep) {
return false;
}
}
JSObject* obj =
js::ErrorObject::create(cx, type, stack, fileName, 0, lineNumber,
columnNumber, std::move(rep), message);
if (!obj) {
return false;
}
rval.setObject(*obj);
return true;
}
const char* js::ValueToSourceForError(JSContext* cx, HandleValue val,
UniqueChars& bytes) {
if (val.isUndefined()) {
return "undefined";
}
if (val.isNull()) {
return "null";
}
AutoClearPendingException acpe(cx);
RootedString str(cx, JS_ValueToSource(cx, val));
if (!str) {
return "<<error converting value to string>>";
}
JSStringBuilder sb(cx);
if (val.isObject()) {
RootedObject valObj(cx, val.toObjectOrNull());
ESClass cls;
if (!GetBuiltinClass(cx, valObj, &cls)) {
return "<<error determining class of value>>";
}
const char* s;
if (cls == ESClass::Array) {
s = "the array ";
} else if (cls == ESClass::ArrayBuffer) {
s = "the array buffer ";
} else if (JS_IsArrayBufferViewObject(valObj)) {
s = "the typed array ";
} else {
s = "the object ";
}
if (!sb.append(s, strlen(s))) {
return "<<error converting value to string>>";
}
} else if (val.isNumber()) {
if (!sb.append("the number ")) {
return "<<error converting value to string>>";
}
} else if (val.isString()) {
if (!sb.append("the string ")) {
return "<<error converting value to string>>";
}
} else if (val.isBigInt()) {
if (!sb.append("the BigInt ")) {
return "<<error converting value to string>>";
}
} else {
MOZ_ASSERT(val.isBoolean() || val.isSymbol());
bytes = StringToNewUTF8CharsZ(cx, *str);
return bytes.get();
}
if (!sb.append(str)) {
return "<<error converting value to string>>";
}
str = sb.finishString();
if (!str) {
return "<<error converting value to string>>";
}
bytes = StringToNewUTF8CharsZ(cx, *str);
return bytes.get();
}
bool js::GetInternalError(JSContext* cx, unsigned errorNumber,
MutableHandleValue error) {
FixedInvokeArgs<1> args(cx);
args[0].set(Int32Value(errorNumber));
return CallSelfHostedFunction(cx, cx->names().GetInternalError,
NullHandleValue, args, error);
}
bool js::GetTypeError(JSContext* cx, unsigned errorNumber,
MutableHandleValue error) {
FixedInvokeArgs<1> args(cx);
args[0].set(Int32Value(errorNumber));
return CallSelfHostedFunction(cx, cx->names().GetTypeError, NullHandleValue,
args, error);
}