js/src/jsapi-tests/testResolveRecursion.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
   2  * vim: set ts=8 sts=2 et sw=2 tw=80:
   3  */
   4 /* This Source Code Form is subject to the terms of the Mozilla Public
   5  * License, v. 2.0. If a copy of the MPL was not distributed with this
   6  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   7
   8 #include "js/Object.h"              // JS::GetReservedSlot, JS::SetReservedSlot
   9 #include "js/PropertyAndElement.h"  // JS_DefineProperty, JS_DefinePropertyById
  10 #include "jsapi-tests/tests.h"
  11
  12 /*
  13  * Test that resolve hook recursion for the same object and property is
  14  * prevented.
  15  */
  16 BEGIN_TEST(testResolveRecursion) {
  17   static const JSClassOps my_resolve_classOps = {
  18       nullptr,     // addProperty
  19       nullptr,     // delProperty
  20       nullptr,     // enumerate
  21       nullptr,     // newEnumerate
  22       my_resolve,  // resolve
  23       nullptr,     // mayResolve
  24       nullptr,     // finalize
  25       nullptr,     // call
  26       nullptr,     // construct
  27       nullptr,     // trace
  28   };
  29
  30   static const JSClass my_resolve_class = {
  31       "MyResolve", JSCLASS_HAS_RESERVED_SLOTS(SlotCount), &my_resolve_classOps};
  32
  33   obj1.init(cx, JS_NewObject(cx, &my_resolve_class));
  34   CHECK(obj1);
  35   obj2.init(cx, JS_NewObject(cx, &my_resolve_class));
  36   CHECK(obj2);
  37   JS::SetReservedSlot(obj1, TestSlot, JS::PrivateValue(this));
  38   JS::SetReservedSlot(obj2, TestSlot, JS::PrivateValue(this));
  39
  40   JS::RootedValue obj1Val(cx, JS::ObjectValue(*obj1));
  41   JS::RootedValue obj2Val(cx, JS::ObjectValue(*obj2));
  42   CHECK(JS_DefineProperty(cx, global, "obj1", obj1Val, 0));
  43   CHECK(JS_DefineProperty(cx, global, "obj2", obj2Val, 0));
  44
  45   resolveEntryCount = 0;
  46   resolveExitCount = 0;
  47
  48   /* Start the essence of the test via invoking the first resolve hook. */
  49   JS::RootedValue v(cx);
  50   EVAL("obj1.x", &v);
  51   CHECK(v.isFalse());
  52   CHECK_EQUAL(resolveEntryCount, 4);
  53   CHECK_EQUAL(resolveExitCount, 4);
  54
  55   obj1 = nullptr;
  56   obj2 = nullptr;
  57   return true;
  58 }
  59
  60 enum Slots { TestSlot, SlotCount };
  61
  62 JS::PersistentRootedObject obj1;
  63 JS::PersistentRootedObject obj2;
  64 int resolveEntryCount;
  65 int resolveExitCount;
  66
  67 struct AutoIncrCounters {
  68   explicit AutoIncrCounters(cls_testResolveRecursion* t) : t(t) {
  69     t->resolveEntryCount++;
  70   }
  71
  72   ~AutoIncrCounters() { t->resolveExitCount++; }
  73
  74   cls_testResolveRecursion* t;
  75 };
  76
  77 bool doResolve(JS::HandleObject obj, JS::HandleId id, bool* resolvedp) {
  78   CHECK_EQUAL(resolveExitCount, 0);
  79   AutoIncrCounters incr(this);
  80   CHECK(obj == obj1 || obj == obj2);
  81
  82   CHECK(id.isString());
  83
  84   JSLinearString* str = JS_EnsureLinearString(cx, id.toString());
  85   CHECK(str);
  86   JS::RootedValue v(cx);
  87   if (JS_LinearStringEqualsLiteral(str, "x")) {
  88     if (obj == obj1) {
  89       /* First resolve hook invocation. */
  90       CHECK_EQUAL(resolveEntryCount, 1);
  91       EVAL("obj2.y = true", &v);
  92       CHECK(v.isTrue());
  93       CHECK(JS_DefinePropertyById(cx, obj, id, JS::FalseHandleValue,
  94                                   JSPROP_RESOLVING));
  95       *resolvedp = true;
  96       return true;
  97     }
  98     if (obj == obj2) {
  99       CHECK_EQUAL(resolveEntryCount, 4);
 100       *resolvedp = false;
 101       return true;
 102     }
 103   } else if (JS_LinearStringEqualsLiteral(str, "y")) {
 104     if (obj == obj2) {
 105       CHECK_EQUAL(resolveEntryCount, 2);
 106       CHECK(JS_DefinePropertyById(cx, obj, id, JS::NullHandleValue,
 107                                   JSPROP_RESOLVING));
 108       EVAL("obj1.x", &v);
 109       CHECK(v.isUndefined());
 110       EVAL("obj1.y", &v);
 111       CHECK(v.isInt32(0));
 112       *resolvedp = true;
 113       return true;
 114     }
 115     if (obj == obj1) {
 116       CHECK_EQUAL(resolveEntryCount, 3);
 117       EVAL("obj1.x", &v);
 118       CHECK(v.isUndefined());
 119       EVAL("obj1.y", &v);
 120       CHECK(v.isUndefined());
 121       EVAL("obj2.y", &v);
 122       CHECK(v.isNull());
 123       EVAL("obj2.x", &v);
 124       CHECK(v.isUndefined());
 125       EVAL("obj1.y = 0", &v);
 126       CHECK(v.isInt32(0));
 127       *resolvedp = true;
 128       return true;
 129     }
 130   }
 131   CHECK(false);
 132   return false;
 133 }
 134
 135 static bool my_resolve(JSContext* cx, JS::HandleObject obj, JS::HandleId id,
 136                        bool* resolvedp) {
 137   void* p = JS::GetReservedSlot(obj, TestSlot).toPrivate();
 138   return static_cast<cls_testResolveRecursion*>(p)->doResolve(obj, id,
 139                                                               resolvedp);
 140 }
 141 END_TEST(testResolveRecursion)
 142
 143 /*
 144  * Test that JS_InitStandardClasses does not cause resolve hooks to be called.
 145  *
 146  * (XPConnect apparently does have global classes, such as the one created by
 147  * nsMessageManagerScriptExecutor::InitChildGlobalInternal(), that have resolve
 148  * hooks which can call back into JS, and on which JS_InitStandardClasses is
 149  * called. Calling back into JS in the middle of resolving `undefined` is bad.)
 150  */
 151 BEGIN_TEST(testResolveRecursion_InitStandardClasses) {
 152   CHECK(JS::InitRealmStandardClasses(cx));
 153   return true;
 154 }
 155
 156 const JSClass* getGlobalClass() override {
 157   static const JSClassOps myGlobalClassOps = {
 158       nullptr,                   // addProperty
 159       nullptr,                   // delProperty
 160       nullptr,                   // enumerate
 161       nullptr,                   // newEnumerate
 162       my_resolve,                // resolve
 163       nullptr,                   // mayResolve
 164       nullptr,                   // finalize
 165       nullptr,                   // call
 166       nullptr,                   // construct
 167       JS_GlobalObjectTraceHook,  // trace
 168   };
 169
 170   static const JSClass myGlobalClass = {
 171       "testResolveRecursion_InitStandardClasses_myGlobalClass",
 172       JSCLASS_GLOBAL_FLAGS, &myGlobalClassOps};
 173
 174   return &myGlobalClass;
 175 }
 176
 177 static bool my_resolve(JSContext* cx, JS::HandleObject obj, JS::HandleId id,
 178                        bool* resolvedp) {
 179   MOZ_ASSERT_UNREACHABLE(
 180       "resolve hook should not be called from InitStandardClasses");
 181   JS_ReportErrorASCII(cx, "FAIL");
 182   return false;
 183 }
 184 END_TEST(testResolveRecursion_InitStandardClasses)