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 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-

  * vim: set ts=8 sw=4 et tw=78:

  *

  * 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/. */

 #include "vm/ErrorObject-inl.h"

 #include "jsexn.h"

 #include "vm/GlobalObject.h"

 #include "jsobjinlines.h"

 #include "vm/Shape-inl.h"

 using namespace js;

 using mozilla::PodZero;

 /* static */ Shape *

 js::ErrorObject::assignInitialShape(ExclusiveContext *cx, Handle<ErrorObject*> obj)

 {

     MOZ_ASSERT(obj->nativeEmpty());

     if (!obj->addDataProperty(cx, cx->names().fileName, FILENAME_SLOT, 0))

         return nullptr;

     if (!obj->addDataProperty(cx, cx->names().lineNumber, LINENUMBER_SLOT, 0))

         return nullptr;

     if (!obj->addDataProperty(cx, cx->names().columnNumber, COLUMNNUMBER_SLOT, 0))

         return nullptr;

     return obj->addDataProperty(cx, cx->names().stack, STACK_SLOT, 0);

 }

 /* static */ bool

 js::ErrorObject::init(JSContext *cx, Handle<ErrorObject*> obj, JSExnType type,

                       ScopedJSFreePtr<JSErrorReport> *errorReport, HandleString fileName,

                       HandleString stack, uint32_t lineNumber, uint32_t columnNumber,

                       HandleString message)

 {

     // Null out early in case of error, for exn_finalize's sake.

     obj->initReservedSlot(ERROR_REPORT_SLOT, PrivateValue(nullptr));

     if (!EmptyShape::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()|.

     RootedShape messageShape(cx);

     if (message) {

         messageShape = obj->addDataProperty(cx, cx->names().message, MESSAGE_SLOT, 0);

         if (!messageShape)

             return false;

         MOZ_ASSERT(messageShape->slot() == MESSAGE_SLOT);

     }

     MOZ_ASSERT(obj->nativeLookupPure(NameToId(cx->names().fileName))->slot() == FILENAME_SLOT);

     MOZ_ASSERT(obj->nativeLookupPure(NameToId(cx->names().lineNumber))->slot() == LINENUMBER_SLOT);

     MOZ_ASSERT(obj->nativeLookupPure(NameToId(cx->names().columnNumber))->slot() ==

                COLUMNNUMBER_SLOT);

     MOZ_ASSERT(obj->nativeLookupPure(NameToId(cx->names().stack))->slot() == STACK_SLOT);

     MOZ_ASSERT_IF(message,

                   obj->nativeLookupPure(NameToId(cx->names().message))->slot() == MESSAGE_SLOT);

     MOZ_ASSERT(JSEXN_ERR <= type && type < JSEXN_LIMIT);

     JSErrorReport *report = errorReport ? errorReport->forget() : nullptr;

     obj->initReservedSlot(EXNTYPE_SLOT, Int32Value(type));

     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));

     obj->initReservedSlot(STACK_SLOT, StringValue(stack));

     if (message)

         obj->nativeSetSlotWithType(cx, messageShape, StringValue(message));

     if (report && report->originPrincipals)

         JS_HoldPrincipals(report->originPrincipals);

     return true;

 }

 /* static */ ErrorObject *

 js::ErrorObject::create(JSContext *cx, JSExnType errorType, HandleString stack,

                         HandleString fileName, uint32_t lineNumber, uint32_t columnNumber,

                         ScopedJSFreePtr<JSErrorReport> *report, HandleString message)

 {

     Rooted<JSObject*> proto(cx, GlobalObject::getOrCreateCustomErrorPrototype(cx, cx->global(), errorType));

     if (!proto)

         return nullptr;

     Rooted<ErrorObject*> errObject(cx);

     {

         JSObject* obj = NewObjectWithGivenProto(cx, &ErrorObject::class_, proto, nullptr);

         if (!obj)

             return nullptr;

         errObject = &obj->as<ErrorObject>();

     }

     if (!ErrorObject::init(cx, errObject, errorType, report, fileName, stack,

                            lineNumber, columnNumber, message))

     {

         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;

     PodZero(&report);

     // Type.

     JSExnType type_ = type();

     report.exnType = type_;

     // Filename.

     JSAutoByteString filenameStr;

     if (!filenameStr.encodeLatin1(cx, fileName(cx)))

         return nullptr;

     report.filename = filenameStr.ptr();

     // Coordinates.

     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;

     if (!message->ensureFlat(cx))

         return nullptr;

     report.ucmessage = message->asFlat().chars();

     // Cache and return.

     JSErrorReport *copy = CopyErrorReport(cx, &report);

     if (!copy)

         return nullptr;

     setReservedSlot(ERROR_REPORT_SLOT, PrivateValue(copy));

     return copy;

 }