diff options
Diffstat (limited to 'dom/bindings/nsScriptErrorWithStack.cpp')
| -rw-r--r-- | dom/bindings/nsScriptErrorWithStack.cpp | 190 |
1 files changed, 190 insertions, 0 deletions
diff --git a/dom/bindings/nsScriptErrorWithStack.cpp b/dom/bindings/nsScriptErrorWithStack.cpp new file mode 100644 index 0000000000..0ba6ab817f --- /dev/null +++ b/dom/bindings/nsScriptErrorWithStack.cpp @@ -0,0 +1,190 @@ +/* -*- 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/. */ + +/* + * nsScriptErrorWithStack implementation. + * a main-thread-only, cycle-collected subclass of nsScriptErrorBase + * that can store a SavedFrame stack trace object. + */ + +#include "nsScriptError.h" +#include "MainThreadUtils.h" +#include "mozilla/Assertions.h" +#include "mozilla/HoldDropJSObjects.h" +#include "mozilla/dom/ScriptSettings.h" +#include "js/Wrapper.h" +#include "nsCycleCollectionParticipant.h" +#include "nsGlobalWindowInner.h" +#include "nsJSUtils.h" + +using namespace mozilla::dom; + +namespace { + +static nsCString FormatStackString(JSContext* cx, JSPrincipals* aPrincipals, + JS::Handle<JSObject*> aStack) { + JS::Rooted<JSString*> formattedStack(cx); + if (!JS::BuildStackString(cx, aPrincipals, aStack, &formattedStack)) { + return nsCString(); + } + + nsAutoJSString stackJSString; + if (!stackJSString.init(cx, formattedStack)) { + return nsCString(); + } + + return NS_ConvertUTF16toUTF8(stackJSString.get()); +} + +} // namespace + +NS_IMPL_CYCLE_COLLECTION_CLASS(nsScriptErrorWithStack) + +NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(nsScriptErrorWithStack) + tmp->mException.setUndefined(); + tmp->mStack = nullptr; + tmp->mStackGlobal = nullptr; +NS_IMPL_CYCLE_COLLECTION_UNLINK_END + +NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(nsScriptErrorWithStack) +NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END + +NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(nsScriptErrorWithStack) + NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mException) + NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mStack) + NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mStackGlobal) +NS_IMPL_CYCLE_COLLECTION_TRACE_END + +NS_IMPL_CYCLE_COLLECTING_ADDREF(nsScriptErrorWithStack) +NS_IMPL_CYCLE_COLLECTING_RELEASE(nsScriptErrorWithStack) + +NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(nsScriptErrorWithStack) + NS_INTERFACE_MAP_ENTRY(nsISupports) + NS_INTERFACE_MAP_ENTRY(nsIConsoleMessage) + NS_INTERFACE_MAP_ENTRY(nsIScriptError) +NS_INTERFACE_MAP_END + +nsScriptErrorWithStack::nsScriptErrorWithStack( + JS::Handle<mozilla::Maybe<JS::Value>> aException, + JS::Handle<JSObject*> aStack, JS::Handle<JSObject*> aStackGlobal) + : mStack(aStack), mStackGlobal(aStackGlobal) { + MOZ_ASSERT(NS_IsMainThread(), "You can't use this class on workers."); + + if (aException.isSome()) { + mHasException = true; + mException.set(*aException); + } else { + mHasException = false; + mException.setUndefined(); + } + + if (mStack) { + MOZ_ASSERT(JS_IsGlobalObject(mStackGlobal)); + js::AssertSameCompartment(mStack, mStackGlobal); + } else { + MOZ_ASSERT(!mStackGlobal); + } + + mozilla::HoldJSObjects(this); +} + +nsScriptErrorWithStack::~nsScriptErrorWithStack() { + mozilla::DropJSObjects(this); +} + +NS_IMETHODIMP +nsScriptErrorWithStack::GetHasException(bool* aHasException) { + *aHasException = mHasException; + return NS_OK; +} + +NS_IMETHODIMP +nsScriptErrorWithStack::GetException(JS::MutableHandle<JS::Value> aException) { + aException.set(mException); + return NS_OK; +} + +NS_IMETHODIMP +nsScriptErrorWithStack::GetStack(JS::MutableHandle<JS::Value> aStack) { + aStack.setObjectOrNull(mStack); + return NS_OK; +} + +NS_IMETHODIMP +nsScriptErrorWithStack::GetStackGlobal( + JS::MutableHandle<JS::Value> aStackGlobal) { + aStackGlobal.setObjectOrNull(mStackGlobal); + return NS_OK; +} + +NS_IMETHODIMP +nsScriptErrorWithStack::ToString(nsACString& /*UTF8*/ aResult) { + MOZ_ASSERT(NS_IsMainThread()); + + nsCString message; + nsresult rv = nsScriptErrorBase::ToString(message); + NS_ENSURE_SUCCESS(rv, rv); + + if (!mStack) { + aResult.Assign(message); + return NS_OK; + } + + AutoJSAPI jsapi; + if (!jsapi.Init(mStackGlobal)) { + return NS_ERROR_FAILURE; + } + + JSPrincipals* principals = + JS::GetRealmPrincipals(js::GetNonCCWObjectRealm(mStackGlobal)); + + JSContext* cx = jsapi.cx(); + JS::Rooted<JSObject*> stack(cx, mStack); + nsCString stackString = FormatStackString(cx, principals, stack); + nsCString combined = message + "\n"_ns + stackString; + aResult.Assign(combined); + + return NS_OK; +} + +static bool IsObjectGlobalDying(JSObject* aObj) { + // CCWs are not associated with a single global + if (js::IsCrossCompartmentWrapper(aObj)) { + return false; + } + + nsGlobalWindowInner* win = xpc::WindowGlobalOrNull(aObj); + return win && win->IsDying(); +} + +already_AddRefed<nsScriptErrorBase> CreateScriptError( + nsGlobalWindowInner* win, JS::Handle<mozilla::Maybe<JS::Value>> aException, + JS::Handle<JSObject*> aStack, JS::Handle<JSObject*> aStackGlobal) { + bool createWithStack = true; + if (aException.isNothing() && !aStack) { + // Neither stack nor exception, do not need nsScriptErrorWithStack. + createWithStack = false; + } else if (win && (win->IsDying() || !win->WindowID())) { + // The window is already dying or we don't have a WindowID, + // this means nsConsoleService::ClearMessagesForWindowID + // would be unable to cleanup this error. + createWithStack = false; + } else if ((aStackGlobal && IsObjectGlobalDying(aStackGlobal)) || + (aException.isSome() && aException.value().isObject() && + IsObjectGlobalDying(&aException.value().toObject()))) { + // Prevent leaks by not creating references to already dying globals. + createWithStack = false; + } + + if (!createWithStack) { + RefPtr<nsScriptErrorBase> error = new nsScriptError(); + return error.forget(); + } + + RefPtr<nsScriptErrorBase> error = + new nsScriptErrorWithStack(aException, aStack, aStackGlobal); + return error.forget(); +} |