Introduce RegistrationServer.

client/registration_protocol_win.h

Index: client/registration_protocol_win.h
diff --git a/client/registration_protocol_win.h b/client/registration_protocol_win.h
new file mode 100644
index 0000000000000000000000000000000000000000..eddf1d1224b355a6a010b2b49facb9a2bde5574c
--- /dev/null
+++ b/client/registration_protocol_win.h
@@ -0,0 +1,44 @@
+// Copyright 2015 The Crashpad Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef CRASHPAD_CLIENT_REGISTRATION_PROTOCOL_WIN_H_
+#define CRASHPAD_CLIENT_REGISTRATION_PROTOCOL_WIN_H_
+
+#include <windows.h>
+#include "util/win/address_types.h"

[scottmg, 2015/05/20 18:53:09]

Blank line before.

[erikwright (departed), 2015/05/20 20:54:13]

Done.

+
+namespace crashpad {
+
+//! \brief A client registration request.
+struct RegistrationRequest {
+  //! \brief The PID of the client process.
+  DWORD client_process_id;
+  //! \brief The address, in the client process address space, of a CrashpadInfo
+  //!     structure.
+  crashpad::WinVMAddress crashpad_info_address;

[scottmg, 2015/05/20 18:53:09]

We should either pragma pack 1 this header, or move the client_process_id below
the crashpad_info_address, otherwise it's sending undefined padding bytes across
the pipe.

[erikwright (departed), 2015/05/20 20:54:13]

Done. I did it separately for each structure to avoid the risk of code being
moved around or unrelated code being inserted between them.

Even though the second one doesn't require it, I think it's best to have it
there now (in case members are added later).

+};
+
+//! \brief  A client registration response.
+struct RegistrationResponse {
+  //! \brief An event handle, valid in the client process, that should be
+  //!     signaled to request a crash report.
+  HANDLE request_report_event;

[scottmg, 2015/05/20 18:53:09]

Will these HANDLEs work correctly when the crash reporter is a 64 bit process
and the target process is x86?

[erikwright (departed), 2015/05/20 20:54:13]

From MSDN
(https://msdn.microsoft.com/en-us/library/windows/desktop/ms724251%28v=vs.85%2...):

DuplicateHandle can be used to duplicate a handle between a 32-bit process and a
64-bit process. The resulting handle is appropriately sized to work in the
target process.

[scottmg, 2015/05/21 02:32:36]

HANDLEs have only 32 significant bits for both x64 and x86, but in sending a
RegistrationResponse across the pipe, won't there be a mismatch in message size
because HANDLE is just a void* of differing size on either side?

[erikwright (departed), 2015/05/21 15:12:37]

Yes you are correct. I thought about declaring something in address_types.h but
it seemed different in usage from WinVMAddress. Let me know if you feel
differently.

+  //! \brief An event handle, valid in the client process, that will be signaled
+  //!     when the requested crash report is complete.
+  HANDLE report_complete_event;
+};
+
+}  // namespace crashpad
+
+#endif  // CRASHPAD_CLIENT_REGISTRATION_PROTOCOL_WIN_H_