Clang plugin to check that unstable types are not used in IPC.

tools/clang/plugins/tests/ipc.cpp

Index: tools/clang/plugins/tests/ipc.cpp
diff --git a/tools/clang/plugins/tests/ipc.cpp b/tools/clang/plugins/tests/ipc.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..b4fb17bd73bb84e0d0a3fb12c7f347aae073864c
--- /dev/null
+++ b/tools/clang/plugins/tests/ipc.cpp
@@ -0,0 +1,346 @@
+// Copyright (c) 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Blacklisted typedefs
+typedef __INTMAX_TYPE__ intmax_t;
+typedef __UINTMAX_TYPE__ uintmax_t;
+typedef int intptr_t;
+typedef unsigned int uintptr_t;
+typedef __WINT_TYPE__ wint_t;
+typedef __SIZE_TYPE__ size_t;
+typedef __SIZE_TYPE__ rsize_t;
+typedef long ssize_t;
+typedef __PTRDIFF_TYPE__ ptrdiff_t;
+typedef unsigned int dev_t;
+typedef int off_t;
+typedef long clock_t;
+typedef int time_t;
+typedef long suseconds_t;
+
+// Other typedefs
+typedef int int32_t;
+typedef unsigned int uint32_t;
+typedef long int64_t;
+typedef unsigned long uint64_t;
+
+namespace std {
+  template <class T>
+  struct allocator {};
+
+  template <class T, class A = allocator<T>>
+  struct vector {};
+
+  template <class F, class S>
+  struct pair {};
+}
+
+namespace base {
+  class Pickle {};
+
+  template <class T, class... Ts>
+  struct Tuple {
+    T value;
+  };
+}
+
+namespace IPC {
+  template <class... T>

[dcheng, 2016/03/07 23:44:39]

No indent in namespace (similar comment above)

+  struct CheckedTuple {
+    typedef base::Tuple<T...> Tuple;
+  };
+
+  template <class T>
+  struct ParamTraits {
+    static void Write(base::Pickle*, const T&) {}
+  };
+
+  template <class T>
+  void WriteParam(base::Pickle* pickle, const T& value) {
+    ParamTraits<T>::Write(pickle, value);
+  }
+}
+
+#if 1

[dcheng, 2016/03/07 23:44:39]

Remove the #if 1's.

+
+/* Test IPC::WriteParam() usage in templates. ERRORS: 6 */
+
+struct Data {
+  uint32_t value;
+  size_t size;
+};
+
+template <>
+struct IPC::ParamTraits<Data> {
+  static void Write(base::Pickle* pickle, const Data& p) {
+    // OK: WriteParam() called in explicit specialization
+    WriteParam(pickle, p.value); // OK
+    WriteParam(pickle, p.size); // ERROR
+  }
+};
+
+template <class T>
+struct Container {
+  T value;
+};
+
+template <class T>
+struct IPC::ParamTraits<Container<T>> {
+  static void Write(base::Pickle* pickle, const Container<T>& container) {
+    // NOT CHECKED: T is not explicitly referenced
+    IPC::WriteParam(pickle, container.value); // NOT CHECKED
+    WriteParam(pickle, container.value); // NOT CHECKED
+
+    // NOT CHECKED: T explicitly referenced
+    IPC::WriteParam<T>(pickle, container.value); // NOT CHECKED
+    WriteParam<T>(pickle, container.value); // NOT CHECKED
+
+    // OK: explicit cast to non-dependent allowed type
+    WriteParam(pickle, static_cast<uint32_t>(container.value)); // OK
+
+    // ERROR: explicit cast to non-dependent banned type
+    WriteParam(pickle, static_cast<long>(container.value)); // ERROR
+  }
+};
+
+template <class T, class... Ts>
+struct MultiContainer {
+  T value;
+};
+
+template <class T, class... Ts>
+struct IPC::ParamTraits<MultiContainer<T, Ts...>> {
+  static void Write(base::Pickle* pickle,
+                    const MultiContainer<T, Ts...>& container) {
+    // NOT CHECKED: template argument explicitly referenced
+    bool helper[] = {
+        (WriteParam<Ts>(pickle, container.value), true)... // NOT CHECKED
+    };
+    (void)helper;
+  }
+};
+
+template <class T>
+struct SomeClass {
+  static void Write(base::Pickle* pickle) {
+    // NOT CHECKED: WriteParam() can only be used in ParamTraits templates

[dcheng, 2016/03/07 23:44:39]

I don't think I understand how this comment relates to 127-129: 128 is still an
error with the ipc checker.

[Dmitry Skiba, 2016/03/08 01:16:11]

Done.

+    IPC::WriteParam(pickle, T(0)); // NOT CHECKED
+    IPC::WriteParam(pickle, size_t(0)); // ERROR
+    IPC::WriteParam(pickle, uint64_t(0)); // OK
+  }
+
+  template <class U>
+  static void WriteEx(base::Pickle* pickle) {
+    // NOT CHECKED: WriteParam() can only be used in ParamTraits templates

[dcheng, 2016/03/07 23:44:39]

Same here.

+    IPC::WriteParam(pickle, U(0)); // NOT CHECKED
+    IPC::WriteParam(pickle, time_t(0)); // ERROR
+    IPC::WriteParam(pickle, uint32_t(0)); // OK
+  }
+};
+
+template <class T>
+void SomeWriteFunction(base::Pickle* pickle) {
+  // NOT CHECKED: WriteParam() can only be used in ParamTraits templates

[dcheng, 2016/03/07 23:44:39]

And here.

+  IPC::WriteParam(pickle, T(0)); // NOT CHECKED
+  IPC::WriteParam(pickle, long(0)); // ERROR
+  IPC::WriteParam(pickle, char(0)); // OK
+
+  [&](){
+    IPC::WriteParam(pickle, T(0)); // NOT CHECKED
+    IPC::WriteParam(pickle, clock_t(0)); // ERROR
+    IPC::WriteParam(pickle, int64_t(0)); // OK
+  }();
+}
+
+void TestWriteParamInTemplates() {
+  // These specializations call WriteParam() on various banned types, either
+  // because they were specified directly (long) or because non-blacklisted
+  // typedef (uint64_t) was stripped down to its underlying type, which is
+  // blacklisted when used as is (unsigned long).
+  // However, since it's hard (if not impossible) to check specializations
+  // properly, we're simply not checking them.
+  SomeClass<long>::Write(nullptr);
+  SomeClass<long>::WriteEx<uint64_t>(nullptr);
+  SomeWriteFunction<uint64_t>(nullptr);
+}
+
+#endif
+
+#if 1
+
+/* Test IPC::CheckedTuple. ERRORS: 5 */
+
+#define IPC_TUPLE(...) IPC::CheckedTuple<__VA_ARGS__>::Tuple
+
+#define IPC_MESSAGE_DECL(name, id, in_tuple) \
+  struct name ## Meta_ ## id { \
+    using InTuple = in_tuple; \
+  };
+
+#define IPC_TEST_MESSAGE(id, in) \
+  IPC_MESSAGE_DECL(TestMessage, id, IPC_TUPLE in)
+
+struct Empty {};
+
+IPC_TEST_MESSAGE(__COUNTER__, (bool, size_t, Empty, long)) // 2 ERRORs
+
+typedef std::vector<long> long1D;
+typedef std::vector<long1D> long2D;
+IPC_TEST_MESSAGE(__COUNTER__, (bool, long2D)) // ERROR
+
+IPC_TEST_MESSAGE(__COUNTER__, (char, short, std::pair<size_t, bool>)) // ERROR
+
+IPC_TEST_MESSAGE(__COUNTER__, (std::vector<std::vector<long&>&>&)) // ERROR
+
+#endif
+
+#if 1
+
+/* Check IPC::WriteParam() arguments. ERRORS: 31 */
+
+// ERRORS: 21
+void TestWriteParamArgument() {
+  #define CALL_WRITEPARAM(Type) \
+    { \
+      Type p; \
+      IPC::WriteParam(nullptr, p); \
+    }
+
+  // ERROR: blacklisted types / typedefs
+  CALL_WRITEPARAM(long) // ERROR
+  CALL_WRITEPARAM(unsigned long) // ERROR
+  CALL_WRITEPARAM(intmax_t) // ERROR
+  CALL_WRITEPARAM(uintmax_t) // ERROR
+  CALL_WRITEPARAM(intptr_t) // ERROR
+  CALL_WRITEPARAM(uintptr_t) // ERROR
+  CALL_WRITEPARAM(wint_t) // ERROR
+  CALL_WRITEPARAM(size_t) // ERROR
+  CALL_WRITEPARAM(rsize_t) // ERROR
+  CALL_WRITEPARAM(ssize_t) // ERROR
+  CALL_WRITEPARAM(ptrdiff_t) // ERROR
+  CALL_WRITEPARAM(dev_t) // ERROR
+  CALL_WRITEPARAM(off_t) // ERROR
+  CALL_WRITEPARAM(clock_t) // ERROR
+  CALL_WRITEPARAM(time_t) // ERROR
+  CALL_WRITEPARAM(suseconds_t) // ERROR
+
+  // ERROR: typedef to blacklisted typedef
+  typedef size_t my_size;
+  CALL_WRITEPARAM(my_size) // ERROR
+
+  // ERROR: expression ends up with type "unsigned long"
+  {
+    uint64_t p = 0;
+    IPC::WriteParam(nullptr, p + 1); // ERROR

[dcheng, 2016/03/07 23:44:39]

Slightly unexpected. I guess this basically shouldn't come up at all though.

[Dmitry Skiba, 2016/03/08 01:16:11]

Yes, p + 1 turns uint64_t into its base type, which is (blacklisted) unsigned
long. The workaround is to add an  explicit cast to a non-blacklisted type.

+  }
+
+  // ERROR: long chain of typedefs, ends up with blacklisted typedef
+  {
+    typedef size_t my_size_base;
+    typedef const my_size_base my_size;
+    typedef my_size& my_size_ref;
+    my_size_ref p = 0;
+    IPC::WriteParam(nullptr, p); // ERROR
+  }
+
+  // ERROR: template specialization references blacklisted type
+  CALL_WRITEPARAM(std::vector<long>) // ERROR
+  CALL_WRITEPARAM(std::vector<size_t>) // ERROR
+
+  // OK: typedef to blacklisted type
+  typedef long my_long;
+  CALL_WRITEPARAM(my_long) // OK
+
+  // OK: other types / typedefs
+  CALL_WRITEPARAM(char) // OK
+  CALL_WRITEPARAM(int) // OK
+  CALL_WRITEPARAM(uint32_t) // OK
+  CALL_WRITEPARAM(int64_t) // OK
+
+  // OK: long chain of typedefs, ends up with non-blacklisted typedef
+  {
+    typedef uint32_t my_int_base;
+    typedef const my_int_base my_int;
+    typedef my_int& my_int_ref;
+    my_int_ref p = 0;
+    IPC::WriteParam(nullptr, p); // OK
+  }
+
+  // OK: template specialization references non-blacklisted type
+  CALL_WRITEPARAM(std::vector<char>) // OK
+  CALL_WRITEPARAM(std::vector<my_long>) // OK
+
+  #undef CALL_WRITEPARAM
+}
+
+struct Provider {
+  typedef unsigned int flags;
+
+  short get_short() const { return 0; }
+  uint64_t get_uint64() const { return 0; }
+  long get_long() const { return 0; }
+  unsigned int get_uint() const { return 0; }
+  flags get_flags() const { return 0; }
+  size_t get_size() const { return 0; }
+
+  const std::vector<size_t>& get_sizes() const { return sizes_data; }
+  const std::vector<uint64_t>& get_uint64s() const { return uint64s_data; }
+
+  template <class T>
+  T get() const { return T(); }
+
+  short short_data;
+  unsigned int uint_data;
+  flags flags_data;
+  long long_data;
+  size_t size_data;
+  uint64_t uint64_data;
+  std::vector<size_t> sizes_data;
+  std::vector<uint64_t> uint64s_data;
+};
+
+// ERRORS: 10
+void TestWriteParamMemberArgument() {
+  Provider p;
+
+  IPC::WriteParam(nullptr, p.get<short>()); // OK
+  IPC::WriteParam(nullptr, p.get_short()); // OK
+  IPC::WriteParam(nullptr, p.short_data); // OK
+
+  IPC::WriteParam(nullptr, p.get<unsigned int>()); // OK
+  IPC::WriteParam(nullptr, p.get_uint()); // OK
+  IPC::WriteParam(nullptr, p.uint_data); // OK
+
+  IPC::WriteParam(nullptr, p.get<Provider::flags>()); // OK
+  IPC::WriteParam(nullptr, p.get_flags()); // OK
+  IPC::WriteParam(nullptr, p.flags_data); // OK
+
+  IPC::WriteParam(nullptr, p.get<long>()); // ERROR
+  IPC::WriteParam(nullptr, p.get_long()); // ERROR
+  IPC::WriteParam(nullptr, p.long_data); // ERROR
+
+  IPC::WriteParam(nullptr, p.get<size_t>()); // ERROR
+  IPC::WriteParam(nullptr, p.get_size()); // ERROR
+  IPC::WriteParam(nullptr, p.size_data); // ERROR
+
+  // Information about uint64_t gets lost, and plugin sees WriteParam()
+  // call on unsigned long, which is blacklisted.
+  IPC::WriteParam(nullptr, p.get<uint64_t>()); // ERROR

[dcheng, 2016/03/07 23:44:39]

I guess this is just for the template case, so maybe it's not too bad.

+  IPC::WriteParam(nullptr, p.get_uint64()); // OK
+  IPC::WriteParam(nullptr, p.uint64_data); // OK
+
+  // Same thing here, WriteParam() sees vector<unsigned long>, and denies it.
+  IPC::WriteParam(nullptr, p.get<std::vector<uint64_t>>()); // ERROR
+  IPC::WriteParam(nullptr, p.get_uint64s()); // OK
+  IPC::WriteParam(nullptr, p.uint64s_data); // OK
+
+  // This one is flaky and depends on whether size_t is typedefed to a
+  // blacklisted type (unsigned long).
+  //IPC::WriteParam(nullptr, p.get<std::vector<uint64_t>>());
+  IPC::WriteParam(nullptr, p.get_sizes()); // ERROR
+  IPC::WriteParam(nullptr, p.sizes_data); // ERROR
+}
+
+#endif
+
+/* ERRORS: 42 */