Revert 69243 - Reland 69237 - Fix raw_scoped_refptr_mismatch_checker.h....

base/raw_scoped_refptr_mismatch_checker.h

Index: base/raw_scoped_refptr_mismatch_checker.h
===================================================================
--- base/raw_scoped_refptr_mismatch_checker.h	(revision 69243)
+++ base/raw_scoped_refptr_mismatch_checker.h	(working copy)
@@ -7,124 +7,165 @@
 #pragma once
 
 #include "base/ref_counted.h"
-#include "base/template_util.h"
 #include "base/tuple.h"
-#include "build/build_config.h"
 
-// It is dangerous to post a task with a T* argument where T is a subtype of
-// RefCounted(Base|ThreadSafeBase), since by the time the parameter is used, the
-// object may already have been deleted since it was not held with a
-// scoped_refptr. Example: http://crbug.com/27191
+// It is dangerous to post a task with a raw pointer argument to a function
+// that expects a scoped_refptr<>.  The compiler will happily accept the
+// situation, but it will not attempt to increase the refcount until the task
+// runs.  Callers expecting the argument to be refcounted up at post time are
+// in for a nasty surprise!  Example: http://crbug.com/27191
 // The following set of traits are designed to generate a compile error
 // whenever this antipattern is attempted.
+template <class A, class B>
+struct ExpectsScopedRefptrButGetsRawPtr {
+  enum { value = 0 };
+};
 
-namespace base {
+template <class A, class B>
+struct ExpectsScopedRefptrButGetsRawPtr<scoped_refptr<A>, B*> {
+  enum { value = 1 };
+};
 
-// This is a base internal implementation file used by task.h and callback.h.
-// Not for public consumption, so we wrap it in namespace internal.
-namespace internal {
+template <class Function, class Params>
+struct FunctionUsesScopedRefptrCorrectly {
+  enum { value = 1 };
+};
 
-template <typename T>
-struct NeedsScopedRefptrButGetsRawPtr {
-#if defined(OS_WIN)
-  enum {
-    value = base::false_type::value
-  };
-#else
-  enum {
-    // Human readable translation: you needed to be a scoped_refptr if you are a
-    // raw pointer type and are convertible to a RefCounted(Base|ThreadSafeBase)
-    // type.
-    value = (is_pointer<T>::value &&
-             (is_convertible<T, subtle::RefCountedBase*>::value ||
-              is_convertible<T, subtle::RefCountedThreadSafeBase*>::value))
-  };
-#endif
+template <class A1, class A2>
+struct FunctionUsesScopedRefptrCorrectly<void (*)(A1), Tuple1<A2> > {
+  enum { value = !ExpectsScopedRefptrButGetsRawPtr<A1, A2>::value };
 };
 
-template <typename Params>
-struct ParamsUseScopedRefptrCorrectly {
-  enum { value = 0 };
+template <class A1, class B1, class A2, class B2>
+struct FunctionUsesScopedRefptrCorrectly<void (*)(A1, B1), Tuple2<A2, B2> > {
+  enum { value = !(ExpectsScopedRefptrButGetsRawPtr<A1, A2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<B1, B2>::value) };
 };
 
-template <>
-struct ParamsUseScopedRefptrCorrectly<Tuple0> {
-  enum { value = 1 };
+template <class A1, class B1, class C1, class A2, class B2, class C2>
+struct FunctionUsesScopedRefptrCorrectly<void (*)(A1, B1, C1),
+                                         Tuple3<A2, B2, C2> > {
+  enum { value = !(ExpectsScopedRefptrButGetsRawPtr<A1, A2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<B1, B2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<C1, C2>::value) };
 };
 
-template <typename A>
-struct ParamsUseScopedRefptrCorrectly<Tuple1<A> > {
-  enum { value = !NeedsScopedRefptrButGetsRawPtr<A>::value };
+template <class A1, class B1, class C1, class D1,
+          class A2, class B2, class C2, class D2>
+struct FunctionUsesScopedRefptrCorrectly<void (*)(A1, B1, C1, D1),
+                                         Tuple4<A2, B2, C2, D2> > {
+  enum { value = !(ExpectsScopedRefptrButGetsRawPtr<A1, A2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<B1, B2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<C1, C2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<D1, D2>::value) };
 };
 
-template <typename A, typename B>
-struct ParamsUseScopedRefptrCorrectly<Tuple2<A, B> > {
-  enum { value = !(NeedsScopedRefptrButGetsRawPtr<A>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<B>::value) };
+template <class A1, class B1, class C1, class D1, class E1,
+          class A2, class B2, class C2, class D2, class E2>
+struct FunctionUsesScopedRefptrCorrectly<void (*)(A1, B1, C1, D1, E1),
+                                         Tuple5<A2, B2, C2, D2, E2> > {
+  enum { value = !(ExpectsScopedRefptrButGetsRawPtr<A1, A2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<B1, B2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<C1, C2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<D1, D2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<E1, E2>::value) };
 };
 
-template <typename A, typename B, typename C>
-struct ParamsUseScopedRefptrCorrectly<Tuple3<A, B, C> > {
-  enum { value = !(NeedsScopedRefptrButGetsRawPtr<A>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<B>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<C>::value) };
+template <class A1, class B1, class C1, class D1, class E1, class F1,
+          class A2, class B2, class C2, class D2, class E2, class F2>
+struct FunctionUsesScopedRefptrCorrectly<void (*)(A1, B1, C1, D1, E1, F1),
+                                         Tuple6<A2, B2, C2, D2, E2, F2> > {
+  enum { value = !(ExpectsScopedRefptrButGetsRawPtr<A1, A2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<B1, B2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<C1, C2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<D1, D2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<E1, E2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<F1, F2>::value) };
 };
 
-template <typename A, typename B, typename C, typename D>
-struct ParamsUseScopedRefptrCorrectly<Tuple4<A, B, C, D> > {
-  enum { value = !(NeedsScopedRefptrButGetsRawPtr<A>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<B>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<C>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<D>::value) };
+template <class A1, class B1, class C1, class D1, class E1, class F1, class G1,
+          class A2, class B2, class C2, class D2, class E2, class F2, class G2>
+struct FunctionUsesScopedRefptrCorrectly<void (*)(A1, B1, C1, D1, E1, F1, G1),
+                                         Tuple7<A2, B2, C2, D2, E2, F2, G2> > {
+  enum { value = !(ExpectsScopedRefptrButGetsRawPtr<A1, A2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<B1, B2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<C1, C2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<D1, D2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<E1, E2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<F1, F2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<G1, G2>::value) };
 };
 
-template <typename A, typename B, typename C, typename D, typename E>
-struct ParamsUseScopedRefptrCorrectly<Tuple5<A, B, C, D, E> > {
-  enum { value = !(NeedsScopedRefptrButGetsRawPtr<A>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<B>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<C>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<D>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<E>::value) };
+template <class Method, class Params>
+struct MethodUsesScopedRefptrCorrectly {
+  enum { value = 1 };
 };
 
-template <typename A, typename B, typename C, typename D, typename E,
-          typename F>
-struct ParamsUseScopedRefptrCorrectly<Tuple6<A, B, C, D, E, F> > {
-  enum { value = !(NeedsScopedRefptrButGetsRawPtr<A>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<B>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<C>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<D>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<E>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<F>::value) };
+template <class T, class A1, class A2>
+struct MethodUsesScopedRefptrCorrectly<void (T::*)(A1), Tuple1<A2> > {
+  enum { value = !ExpectsScopedRefptrButGetsRawPtr<A1, A2>::value };
 };
 
-template <typename A, typename B, typename C, typename D, typename E,
-          typename F, typename G>
-struct ParamsUseScopedRefptrCorrectly<Tuple7<A, B, C, D, E, F, G> > {
-  enum { value = !(NeedsScopedRefptrButGetsRawPtr<A>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<B>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<C>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<D>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<E>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<F>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<G>::value) };
+template <class T, class A1, class B1, class A2, class B2>
+struct MethodUsesScopedRefptrCorrectly<void (T::*)(A1, B1), Tuple2<A2, B2> > {
+  enum { value = !(ExpectsScopedRefptrButGetsRawPtr<A1, A2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<B1, B2>::value) };
 };
 
-template <typename A, typename B, typename C, typename D, typename E,
-          typename F, typename G, typename H>
-struct ParamsUseScopedRefptrCorrectly<Tuple8<A, B, C, D, E, F, G, H> > {
-  enum { value = !(NeedsScopedRefptrButGetsRawPtr<A>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<B>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<C>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<D>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<E>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<F>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<G>::value ||
-                   NeedsScopedRefptrButGetsRawPtr<H>::value) };
+template <class T, class A1, class B1, class C1,
+                   class A2, class B2, class C2>
+struct MethodUsesScopedRefptrCorrectly<void (T::*)(A1, B1, C1),
+                                       Tuple3<A2, B2, C2> > {
+  enum { value = !(ExpectsScopedRefptrButGetsRawPtr<A1, A2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<B1, B2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<C1, C2>::value) };
 };
 
-}  // namespace internal
+template <class T, class A1, class B1, class C1, class D1,
+          class A2, class B2, class C2, class D2>
+struct MethodUsesScopedRefptrCorrectly<void (T::*)(A1, B1, C1, D1),
+                                       Tuple4<A2, B2, C2, D2> > {
+  enum { value = !(ExpectsScopedRefptrButGetsRawPtr<A1, A2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<B1, B2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<C1, C2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<D1, D2>::value) };
+};
 
-}  // namespace base
+template <class T, class A1, class B1, class C1, class D1, class E1,
+                   class A2, class B2, class C2, class D2, class E2>
+struct MethodUsesScopedRefptrCorrectly<void (T::*)(A1, B1, C1, D1, E1),
+                                       Tuple5<A2, B2, C2, D2, E2> > {
+  enum { value = !(ExpectsScopedRefptrButGetsRawPtr<A1, A2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<B1, B2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<C1, C2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<D1, D2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<E1, E2>::value) };
+};
 
+template <class T, class A1, class B1, class C1, class D1, class E1, class F1,
+                   class A2, class B2, class C2, class D2, class E2, class F2>
+struct MethodUsesScopedRefptrCorrectly<void (T::*)(A1, B1, C1, D1, E1, F1),
+                                       Tuple6<A2, B2, C2, D2, E2, F2> > {
+  enum { value = !(ExpectsScopedRefptrButGetsRawPtr<A1, A2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<B1, B2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<C1, C2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<D1, D2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<E1, E2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<F1, F2>::value) };
+};
+
+template <class T,
+          class A1, class B1, class C1, class D1, class E1, class F1, class G1,
+          class A2, class B2, class C2, class D2, class E2, class F2, class G2>
+struct MethodUsesScopedRefptrCorrectly<void (T::*)(A1, B1, C1, D1, E1, F1, G1),
+                                       Tuple7<A2, B2, C2, D2, E2, F2, G2> > {
+  enum { value = !(ExpectsScopedRefptrButGetsRawPtr<A1, A2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<B1, B2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<C1, C2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<D1, D2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<E1, E2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<F1, F2>::value ||
+                   ExpectsScopedRefptrButGetsRawPtr<G1, G2>::value) };
+};
+
 #endif  // BASE_RAW_SCOPED_REFPTR_MISMATCH_CHECKER_H_