win: Make reading NT_IMAGE_HEADERS work cross-bitness

test/win/child_launcher.cc

+// 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.
+
+#include "test/win/child_launcher.h"
+
+#include "gtest/gtest.h"
+
+namespace crashpad {
+
+ChildLauncher::ChildLauncher(const std::wstring& executable,
+                             const std::wstring& command_line)
+    : executable_(executable),
+      command_line_(command_line),
+      process_handle_(),
+      main_thread_handle_(),
+      stdout_read_handle_() {
+}
+
+ChildLauncher::~ChildLauncher() {
+  EXPECT_EQ(WAIT_OBJECT_0,
+            WaitForSingleObject(process_handle_.get(), INFINITE));
+}
+
+void ChildLauncher::Start() {
+  // Create a pipe for the stdout of the child.
+  SECURITY_ATTRIBUTES security_attributes = {0};
+  security_attributes.nLength = sizeof(SECURITY_ATTRIBUTES);
+  security_attributes.bInheritHandle = true;
+  HANDLE stdout_read;
+  HANDLE stdout_write;
+  ASSERT_TRUE(CreatePipe(&stdout_read, &stdout_write, &security_attributes, 0));
+  stdout_read_handle_.reset(stdout_read);

[Mark Mentovai, 2015/09/19 03:02:47]

ASSERT_FALSE(stdout_read_handle_) first to ensure no abuse. You can do this up
at the top of this method, too. Same for the other two handles.

[scottmg, 2015/09/19 04:24:41]

Done.

+  ScopedFileHANDLE write_handle(stdout_write);
+  ASSERT_TRUE(
+      SetHandleInformation(stdout_read_handle_.get(), HANDLE_FLAG_INHERIT, 0));
+
+  STARTUPINFO startup_info = {0};
+  startup_info.cb = sizeof(startup_info);
+  startup_info.hStdInput = GetStdHandle(STD_INPUT_HANDLE);
+  startup_info.hStdOutput = write_handle.get();
+  startup_info.hStdError = GetStdHandle(STD_ERROR_HANDLE);
+  startup_info.dwFlags = STARTF_USESTDHANDLES;
+  PROCESS_INFORMATION process_information;
+  std::wstring command_line = executable_ + L" " + command_line_;

[Mark Mentovai, 2015/09/19 03:02:47]

Some sort of escaping (CRT-compatible, I guess) should be applied to
executable_. We may already have a helper for that somewhere?

[scottmg, 2015/09/19 04:24:41]

Done.

+  ASSERT_TRUE(CreateProcess(executable_.c_str(),
+                            &command_line[0],
+                            nullptr,
+                            nullptr,
+                            true,
+                            0,
+                            nullptr,
+                            nullptr,
+                            &startup_info,
+                            &process_information));
+  // Take ownership of the two process handles returned.
+  main_thread_handle_.reset(process_information.hThread);
+  process_handle_.reset(process_information.hProcess);
+}
+
+}  // namespace crashpad