Bug 891177 - Add ReentrancyGuard.h as a helper class for asserting that use of a class is non-reentrant. r=terrence

--HG--
extra : rebase_source : 3751e523c0b0315697cb6e005dfd8ee625f6dd58

js/public/HashTable.h

@@ -14,6 +14,7 @@
 #include "mozilla/MemoryReporting.h"
 #include "mozilla/Move.h"
 #include "mozilla/PodOperations.h"
+#include "mozilla/ReentrancyGuard.h"
 #include "mozilla/TypeTraits.h"
 #include "mozilla/Util.h"
 
@@ -879,7 +880,7 @@ class HashTable : private AllocPolicy
 #   define METER(x)
 #endif
 
-    friend class js::ReentrancyGuard;
+    friend class mozilla::ReentrancyGuard;
     mutable mozilla::DebugOnly<bool> entered;
     mozilla::DebugOnly<uint64_t>     mutationCount;
 
@@ -1355,7 +1356,7 @@ class HashTable : private AllocPolicy
 
     Ptr lookup(const Lookup &l) const
     {
-        ReentrancyGuard g(*this);
+        mozilla::ReentrancyGuard g(*this);
         HashNumber keyHash = prepareHash(l);
         return Ptr(lookup(l, keyHash, 0));
     }
@@ -1368,7 +1369,7 @@ class HashTable : private AllocPolicy
 
     AddPtr lookupForAdd(const Lookup &l) const
     {
-        ReentrancyGuard g(*this);
+        mozilla::ReentrancyGuard g(*this);
         HashNumber keyHash = prepareHash(l);
         Entry &entry = lookup(l, keyHash, sCollisionBit);
         AddPtr p(entry, keyHash);
@@ -1379,7 +1380,7 @@ class HashTable : private AllocPolicy
     template <class U>
     bool add(AddPtr &p, const U &rhs)
     {
-        ReentrancyGuard g(*this);
+        mozilla::ReentrancyGuard g(*this);
         JS_ASSERT(mutationCount == p.mutationCount);
         JS_ASSERT(table);
         JS_ASSERT(!p.found());
@@ -1440,7 +1441,7 @@ class HashTable : private AllocPolicy
     {
         p.mutationCount = mutationCount;
         {
-            ReentrancyGuard g(*this);
+            mozilla::ReentrancyGuard g(*this);
             p.entry_ = &lookup(l, p.keyHash, sCollisionBit);
         }
         return p.found() || add(p, u);
@@ -1449,7 +1450,7 @@ class HashTable : private AllocPolicy
     void remove(Ptr p)
     {
         JS_ASSERT(table);
-        ReentrancyGuard g(*this);
+        mozilla::ReentrancyGuard g(*this);
         JS_ASSERT(p.found());
         remove(*p.entry_);
         checkUnderloaded();
@@ -1458,7 +1459,7 @@ class HashTable : private AllocPolicy
     void rekey(Ptr p, const Lookup &l, const Key &k)
     {
         JS_ASSERT(table);
-        ReentrancyGuard g(*this);
+        mozilla::ReentrancyGuard g(*this);
         JS_ASSERT(p.found());
         typename HashTableEntry<T>::NonConstT t(mozilla::Move(*p));
         HashPolicy::setKey(t, const_cast<Key &>(k));

js/public/Utility.h

@@ -564,38 +564,6 @@ SCOPED_TEMPLATE(ScopedReleasePtr, ScopedReleasePtrTraits)
 
 namespace js {
 
-/* Useful for implementing containers that assert non-reentrancy */
-class ReentrancyGuard
-{
-    /* ReentrancyGuard is not copyable. */
-    ReentrancyGuard(const ReentrancyGuard &);
-    void operator=(const ReentrancyGuard &);
-
-#ifdef DEBUG
-    bool &entered;
-#endif
-  public:
-    template <class T>
-#ifdef DEBUG
-    ReentrancyGuard(T &obj)
-      : entered(obj.entered)
-#else
-    ReentrancyGuard(T &/*obj*/)
-#endif
-    {
-#ifdef DEBUG
-        JS_ASSERT(!entered);
-        entered = true;
-#endif
-    }
-    ~ReentrancyGuard()
-    {
-#ifdef DEBUG
-        entered = false;
-#endif
-    }
-};
-
 template <class T>
 JS_ALWAYS_INLINE static void
 Swap(T &t, T &u)

js/public/Vector.h

@@ -11,6 +11,7 @@
 #include "mozilla/Attributes.h"
 #include "mozilla/MemoryReporting.h"
 #include "mozilla/Move.h"
+#include "mozilla/ReentrancyGuard.h"
 #include "mozilla/TypeTraits.h"
 
 #include "js/TemplateLib.h"
@@ -261,7 +262,7 @@ class Vector : private AllocPolicy
     mozilla::AlignedStorage<sInlineBytes> storage;
 
 #ifdef DEBUG
-    friend class ReentrancyGuard;
+    friend class mozilla::ReentrancyGuard;
     bool entered;
 #endif
 
@@ -524,7 +525,7 @@ class Vector : private AllocPolicy
 
 /* This does the re-entrancy check plus several other sanity checks. */
 #define REENTRANCY_GUARD_ET_AL \
-    ReentrancyGuard g(*this); \
+    mozilla::ReentrancyGuard g(*this); \
     MOZ_ASSERT_IF(usingInlineStorage(), mCapacity == sInlineCapacity); \
     MOZ_ASSERT(reserved() <= mCapacity); \
     MOZ_ASSERT(mLength <= reserved()); \

mfbt/ReentrancyGuard.h

@@ -0,0 +1,56 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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/. */
+
+/* Small helper class for asserting uses of a class are non-reentrant. */
+
+#ifndef mozilla_ReentrancyGuard_h_
+#define mozilla_ReentrancyGuard_h_
+
+#include "mozilla/Assertions.h"
+#include "mozilla/Attributes.h"
+#include "mozilla/GuardObjects.h"
+
+namespace mozilla {
+
+/* Useful for implementing containers that assert non-reentrancy */
+class ReentrancyGuard
+{
+    MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
+#ifdef DEBUG
+    bool& entered;
+#endif
+
+  public:
+    template<class T>
+#ifdef DEBUG
+    ReentrancyGuard(T& obj
+                    MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
+      : entered(obj.entered)
+#else
+    ReentrancyGuard(T&
+                    MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
+#endif
+    {
+      MOZ_GUARD_OBJECT_NOTIFIER_INIT;
+#ifdef DEBUG
+      MOZ_ASSERT(!entered);
+      entered = true;
+#endif
+    }
+    ~ReentrancyGuard()
+    {
+#ifdef DEBUG
+      entered = false;
+#endif
+    }
+
+  private:
+    ReentrancyGuard(const ReentrancyGuard&) MOZ_DELETE;
+    void operator=(const ReentrancyGuard&) MOZ_DELETE;
+};
+
+} // namespace mozilla
+
+#endif // mozilla_ReentrancyGuard_h_

mfbt/exported_headers.mk

@@ -38,6 +38,7 @@ EXPORTS_mozilla += \
   Poison.h \
   Range.h \
   RangedPtr.h \
+  ReentrancyGuard.h \
   RefPtr.h \
   Scoped.h \
   SHA1.h \