Make the implementation .cc files go away, instead have the authors give us a...

ipc/ipc_param_traits_log_macros.h

+// Copyright (c) 2011 The Chromium Authors. All rights reserved.

[jam, 2011/02/09 23:06:15]

nit: i think all the ipc_param_* files can lose the "ipc_" prefix

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef IPC_IPC_PARAM_TRAITS_LOG_MACROS_H_
+#define IPC_IPC_PARAM_TRAITS_LOG_MACROS_H_
+
+#include <string>
+
+// Null out all the macros that need nulling.
+#include "ipc/ipc_message_null_macros.h"
+
+// STRUCT declarations cause corresponding STRUCT_TRAITS declarations to occur.
+#undef IPC_STRUCT_BEGIN
+#undef IPC_STRUCT_MEMBER
+#undef IPC_STRUCT_END
+#define IPC_STRUCT_BEGIN(struct_name) IPC_STRUCT_TRAITS_BEGIN(struct_name)
+#define IPC_STRUCT_MEMBER(type, name) IPC_STRUCT_TRAITS_MEMBER(name)
+#define IPC_STRUCT_END() IPC_STRUCT_TRAITS_END()
+
+// Set up so next include will generate log methods.
+#undef IPC_STRUCT_TRAITS_BEGIN
+#undef IPC_STRUCT_TRAITS_MEMBER
+#undef IPC_STRUCT_TRAITS_END
+#define IPC_STRUCT_TRAITS_BEGIN(struct_name) \
+  void ParamTraits<struct_name>::Log(const param_type& p, std::string* l) { \
+    bool needs_comma = false; \
+    l->append("(");
+#define IPC_STRUCT_TRAITS_MEMBER(name) \
+    if (needs_comma) \
+      l->append(", "); \
+    LogParam(p.name, l); \
+    needs_comma = true;
+#define IPC_STRUCT_TRAITS_END() \
+    l->append(")"); \
+  }
+
+#undef IPC_ENUM_TRAITS
+#define IPC_ENUM_TRAITS(enum_name) \
+  void ParamTraits<enum_name>::Log(const param_type& p, std::string* l) { \
+    LogParam(static_cast<int>(p), l); \
+  }
+
+#endif  // IPC_IPC_PARAM_TRAITS_LOG_MACROS_H_
+