win: Make reading CrashpadInfo work across bitness

test/win/child_launcher.h

 // 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_TEST_WIN_CHILD_LAUNCHER_H_
 #define CRASHPAD_TEST_WIN_CHILD_LAUNCHER_H_
 
 #include <windows.h>
 
 #include <string>
 
 #include "util/win/scoped_handle.h"
 
 namespace crashpad {
 namespace test {
 
 //! \brief Creates a child process for testing. Uses gtest `ASSERT_*` to
 //!     indicate failure. The child's output is passed through a pipe and is
-//!     available via stdout_read_handle().
+//!     available via stdout_read_handle(), and the child's input is attached to
+//!     a second pipe available via stdin_write_handle().
 class ChildLauncher {
  public:
   //! \brief Creates the object. \a executable will be escaped and prepended to
   //!     \a command_line to build the command line of the child.
   ChildLauncher(const std::wstring& executable,
                 const std::wstring& command_line);
 
   ~ChildLauncher();
 
   //! \brief Starts the child process, after which the handle functions below
   //!     will be valid.
   void Start();
 
+  //! \brief Waits for the child process to exit.
+  //! 
+  //! \return The process exit code.
+  DWORD WaitForExit();
+
   //! \brief The child process's `HANDLE`.
   HANDLE process_handle() const { return process_handle_.get(); }
 
   //! \brief The child process's main thread's `HANDLE`.
   HANDLE main_thread_handle() const { return main_thread_handle_.get(); }
 
   //! \brief The read end of a pipe attached to the child's stdout.
   HANDLE stdout_read_handle() const { return stdout_read_handle_.get(); }
 
+  //! \brief The write end of a pipe attached to the child's stdin.
+  HANDLE stdin_write_handle() const { return stdin_write_handle_.get(); }
+
  private:
   std::wstring executable_;
   std::wstring command_line_;
   ScopedKernelHANDLE process_handle_;
   ScopedKernelHANDLE main_thread_handle_;
   ScopedFileHANDLE stdout_read_handle_;
+  ScopedFileHANDLE stdin_write_handle_;
 };
 
 //! \brief Utility function for building escaped command lines.
 //!
 //! \param[in] argument Appended to \a command_line surrounded by properly
 //!     escaped quotation marks, if necessary.
 //! \param[inout] command_line The command line being constructed.
 void AppendCommandLineArgument(const std::wstring& argument,
                                std::wstring* command_line);
 
 }  // namespace test
 }  // namespace crashpad
 
 #endif  // CRASHPAD_TEST_WIN_CHILD_LAUNCHER_H_