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 {
+namespace test {
+
+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() {
+  ASSERT_FALSE(process_handle_.is_valid());
+  ASSERT_FALSE(main_thread_handle_.is_valid());
+  ASSERT_FALSE(stdout_read_handle_.is_valid());
+
+  // 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);
+  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;
+  AppendCommandLineArgument(executable_, &command_line);
+  command_line += L" ";
+  command_line += command_line_;
+  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);
+}
+
+// Ref: http://blogs.msdn.com/b/twistylittlepassagesallalike/archive/2011/04/23/everyone-quotes-arguments-the-wrong-way.aspx
+void AppendCommandLineArgument(const std::wstring& argument,
+                               std::wstring* command_line) {
+  // Don't bother quoting if unnecessary.
+  if (!argument.empty() &&
+      argument.find_first_of(L" \t\n\v\"") == std::wstring::npos) {
+    command_line->append(argument);
+  } else {
+    command_line->push_back(L'"');
+    for (std::wstring::const_iterator i = argument.begin();; ++i) {
+      size_t backslash_count = 0;
+      while (i != argument.end() && *i == L'\\') {
+        ++i;
+        ++backslash_count;
+      }
+      if (i == argument.end()) {
+        // Escape all backslashes, but let the terminating double quotation mark
+        // we add below be interpreted as a metacharacter.
+        command_line->append(backslash_count * 2, L'\\');
+        break;
+      } else if (*i == L'"') {
+        // Escape all backslashes and the following double quotation mark.
+        command_line->append(backslash_count * 2 + 1, L'\\');
+        command_line->push_back(*i);
+      } else {
+        // Backslashes aren't special here.
+        command_line->append(backslash_count, L'\\');
+        command_line->push_back(*i);
+      }
+    }
+    command_line->push_back(L'"');
+  }
+}
+
+}  // namespace test
+}  // namespace crashpad