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",
  32       JSCLASS_HAS_RESERVED_SLOTS(SlotCount),
  33       &my_resolve_classOps,
  34   };
  35
  36   obj1.init(cx, JS_NewObject(cx, &my_resolve_class));
  37   CHECK(obj1);
  38   obj2.init(cx, JS_NewObject(cx, &my_resolve_class));
  39   CHECK(obj2);
  40   JS::SetReservedSlot(obj1, TestSlot, JS::PrivateValue(this));
  41   JS::SetReservedSlot(obj2, TestSlot, JS::PrivateValue(this));
  42
  43   JS::RootedValue obj1Val(cx, JS::ObjectValue(*obj1));
  44   JS::RootedValue obj2Val(cx, JS::ObjectValue(*obj2));
  45   CHECK(JS_DefineProperty(cx, global, "obj1", obj1Val, 0));
  46   CHECK(JS_DefineProperty(cx, global, "obj2", obj2Val, 0));
  47
  48   resolveEntryCount = 0;
  49   resolveExitCount = 0;
  50
  51   /* Start the essence of the test via invoking the first resolve hook. */
  52   JS::RootedValue v(cx);
  53   EVAL("obj1.x", &v);
  54   CHECK(v.isFalse());
  55   CHECK_EQUAL(resolveEntryCount, 4);
  56   CHECK_EQUAL(resolveExitCount, 4);
  57
  58   obj1 = nullptr;
  59   obj2 = nullptr;
  60   return true;
  61 }
  62
  63 enum Slots { TestSlot, SlotCount };
  64
  65 JS::PersistentRootedObject obj1;
  66 JS::PersistentRootedObject obj2;
  67 int resolveEntryCount;
  68 int resolveExitCount;
  69
  70 struct AutoIncrCounters {
  71   explicit AutoIncrCounters(cls_testResolveRecursion* t) : t(t) {
  72     t->resolveEntryCount++;
  73   }
  74
  75   ~AutoIncrCounters() { t->resolveExitCount++; }
  76
  77   cls_testResolveRecursion* t;
  78 };
  79
  80 bool doResolve(JS::HandleObject obj, JS::HandleId id, bool* resolvedp) {
  81   CHECK_EQUAL(resolveExitCount, 0);
  82   AutoIncrCounters incr(this);
  83   CHECK(obj == obj1 || obj == obj2);
  84
  85   CHECK(id.isString());
  86
  87   JSLinearString* str = JS_EnsureLinearString(cx, id.toString());
  88   CHECK(str);
  89   JS::RootedValue v(cx);
  90   if (JS_LinearStringEqualsLiteral(str, "x")) {
  91     if (obj == obj1) {
  92       /* First resolve hook invocation. */
  93       CHECK_EQUAL(resolveEntryCount, 1);
  94       EVAL("obj2.y = true", &v);
  95       CHECK(v.isTrue());
  96       CHECK(JS_DefinePropertyById(cx, obj, id, JS::FalseHandleValue,
  97                                   JSPROP_RESOLVING));
  98       *resolvedp = true;
  99       return true;
 100     }
 101     if (obj == obj2) {
 102       CHECK_EQUAL(resolveEntryCount, 4);
 103       *resolvedp = false;
 104       return true;
 105     }
 106   } else if (JS_LinearStringEqualsLiteral(str, "y")) {
 107     if (obj == obj2) {
 108       CHECK_EQUAL(resolveEntryCount, 2);
 109       CHECK(JS_DefinePropertyById(cx, obj, id, JS::NullHandleValue,
 110                                   JSPROP_RESOLVING));
 111       EVAL("obj1.x", &v);
 112       CHECK(v.isUndefined());
 113       EVAL("obj1.y", &v);
 114       CHECK(v.isInt32(0));
 115       *resolvedp = true;
 116       return true;
 117     }
 118     if (obj == obj1) {
 119       CHECK_EQUAL(resolveEntryCount, 3);
 120       EVAL("obj1.x", &v);
 121       CHECK(v.isUndefined());
 122       EVAL("obj1.y", &v);
 123       CHECK(v.isUndefined());
 124       EVAL("obj2.y", &v);
 125       CHECK(v.isNull());
 126       EVAL("obj2.x", &v);
 127       CHECK(v.isUndefined());
 128       EVAL("obj1.y = 0", &v);
 129       CHECK(v.isInt32(0));
 130       *resolvedp = true;
 131       return true;
 132     }
 133   }
 134   CHECK(false);
 135   return false;
 136 }
 137
 138 static bool my_resolve(JSContext* cx, JS::HandleObject obj, JS::HandleId id,
 139                        bool* resolvedp) {
 140   void* p = JS::GetReservedSlot(obj, TestSlot).toPrivate();
 141   return static_cast<cls_testResolveRecursion*>(p)->doResolve(obj, id,
 142                                                               resolvedp);
 143 }
 144 END_TEST(testResolveRecursion)
 145
 146 /*
 147  * Test that JS_InitStandardClasses does not cause resolve hooks to be called.
 148  *
 149  * (XPConnect apparently does have global classes, such as the one created by
 150  * nsMessageManagerScriptExecutor::InitChildGlobalInternal(), that have resolve
 151  * hooks which can call back into JS, and on which JS_InitStandardClasses is
 152  * called. Calling back into JS in the middle of resolving `undefined` is bad.)
 153  */
 154 BEGIN_TEST(testResolveRecursion_InitStandardClasses) {
 155   CHECK(JS::InitRealmStandardClasses(cx));
 156   return true;
 157 }
 158
 159 const JSClass* getGlobalClass() override {
 160   static const JSClassOps myGlobalClassOps = {
 161       nullptr,                   // addProperty
 162       nullptr,                   // delProperty
 163       nullptr,                   // enumerate
 164       nullptr,                   // newEnumerate
 165       my_resolve,                // resolve
 166       nullptr,                   // mayResolve
 167       nullptr,                   // finalize
 168       nullptr,                   // call
 169       nullptr,                   // construct
 170       JS_GlobalObjectTraceHook,  // trace
 171   };
 172
 173   static const JSClass myGlobalClass = {
 174       "testResolveRecursion_InitStandardClasses_myGlobalClass",
 175       JSCLASS_GLOBAL_FLAGS,
 176       &myGlobalClassOps,
 177   };
 178
 179   return &myGlobalClass;
 180 }
 181
 182 static bool my_resolve(JSContext* cx, JS::HandleObject obj, JS::HandleId id,
 183                        bool* resolvedp) {
 184   MOZ_ASSERT_UNREACHABLE(
 185       "resolve hook should not be called from InitStandardClasses");
 186   JS_ReportErrorASCII(cx, "FAIL");
 187   return false;
 188 }
 189 END_TEST(testResolveRecursion_InitStandardClasses)