Browser watcher first installment.

components/browser_watcher/watcher_win_unittest.cc

Index: components/browser_watcher/watcher_win_unittest.cc
diff --git a/components/browser_watcher/watcher_win_unittest.cc b/components/browser_watcher/watcher_win_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..69b867547aa43d8890cf9fd935a1ef29c5cdcc81
--- /dev/null
+++ b/components/browser_watcher/watcher_win_unittest.cc
@@ -0,0 +1,212 @@
+// Copyright (c) 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "components/browser_watcher/watcher_win.h"
+
+#include "base/command_line.h"
+#include "base/process/kill.h"
+#include "base/strings/string_util.h"
+#include "base/strings/stringprintf.h"
+#include "base/synchronization/waitable_event.h"
+#include "base/test/multiprocess_test.h"
+#include "base/test/test_reg_util_win.h"
+#include "base/threading/platform_thread.h"
+#include "base/time/time.h"
+#include "base/win/scoped_handle.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "testing/multiprocess_func_list.h"
+
+namespace browser_watcher {
+
+namespace {
+
+const wchar_t kRegistryPath[] = L"Software\\BrowserWatcherTest";
+
+MULTIPROCESS_TEST_MAIN(Sleeper) {
+  // Sleep forever - the test harness will kill this process to give it an
+  // exit code.
+  base::PlatformThread::Sleep(base::TimeDelta::FromMilliseconds(INFINITE));
+  return 1;
+}
+
+class ScopedSleeperProcess {
+ public:
+   ScopedSleeperProcess() :
+      process_(base::kNullProcessHandle), is_killed_(false) {

[erikwright (departed), 2014/11/17 18:12:30]

process_id_ should be initialized

[Sigurður Ásgeirsson, 2014/11/17 21:27:12]

Done.

+  }
+
+  ~ScopedSleeperProcess() {
+    if (process_ != base::kNullProcessHandle) {
+      base::KillProcess(process_, -1, true);
+      base::CloseProcessHandle(process_);
+    }
+  }
+
+  void Launch() {
+    ASSERT_EQ(base::kNullProcessHandle, process_);

[erikwright (departed), 2014/11/17 18:12:31]

I'm personally opposed to using "ASSERT" in functions/methods besides the main
test body. The reasoning being that it is a hidden return, but doesn't actually
have the "expected" effect of terminating the test.

I would use EXPECT in such cases. I don't insist on it, though.

[Sigurður Ásgeirsson, 2014/11/17 21:27:12]

Hmmm - there's an implicit return value in such test functions, see
ASSERT_NO_FATAL_FAILURE.

+
+    base::CommandLine cmd_line(base::GetMultiProcessTestChildBaseCommandLine());
+    base::LaunchOptions options;
+    options.start_hidden = true;
+    process_ = base::SpawnMultiProcessTestChild("Sleeper", cmd_line, options);
+    process_id_ = base::GetProcId(process_);
+    ASSERT_NE(base::kNullProcessHandle, process_);
+  }
+
+  void Kill(int exit_code, bool wait) {
+    ASSERT_NE(process_, base::kNullProcessHandle);
+    ASSERT_FALSE(is_killed_);
+    ASSERT_TRUE(base::KillProcess(process_, exit_code, wait));
+    is_killed_ = true;
+  }
+
+  base::ProcessHandle process() const { return process_; }
+  base::ProcessId process_id() const { return process_id_; }
+  void set_process(base::ProcessHandle process)  {  process_ = process; }
+
+ private:
+  base::ProcessHandle process_;
+  base::ProcessId process_id_;
+  bool is_killed_;
+};
+
+class BrowserWatcherTest : public testing::Test {
+ public:
+  typedef testing::Test Super;
+
+  static const int kExitCode = 0xCAFEBABE;
+
+  BrowserWatcherTest() :
+      cmd_line_(base::CommandLine::NO_PROGRAM),
+      process_(base::kNullProcessHandle) {
+  }
+
+  virtual void SetUp() override {
+    Super::SetUp();
+
+    override_manager_.OverrideRegistry(HKEY_CURRENT_USER);
+  }
+
+  virtual void TearDown() override {
+    if (process_ != base::kNullProcessHandle) {
+      base::CloseProcessHandle(process_);
+      process_ = base::kNullProcessHandle;
+    }
+
+    Super::TearDown();
+  }
+
+  void OpenSelfWithAccess(uint32 access) {
+    ASSERT_EQ(base::kNullProcessHandle, process_);
+    ASSERT_TRUE(base::OpenProcessHandleWithAccess(
+        base::GetCurrentProcId(), access, &process_));
+  }
+
+  void VerifyWroteExitCode(base::ProcessId proc_id, int exit_code) {
+    base::win::RegistryValueIterator it(
+          HKEY_CURRENT_USER, kRegistryPath);
+
+    ASSERT_EQ(1, it.ValueCount());
+    base::win::RegKey key(HKEY_CURRENT_USER,
+                          kRegistryPath,
+                          KEY_QUERY_VALUE);
+
+    // The value name should encode the process id at the start.
+    EXPECT_TRUE(StartsWith(it.Name(),
+                           base::StringPrintf(L"%d-", proc_id),
+                           false));
+    DWORD value = 0;
+    ASSERT_EQ(ERROR_SUCCESS, key.ReadValueDW(it.Name(), &value));
+    ASSERT_EQ(exit_code, value);
+  }
+
+ protected:
+  base::CommandLine cmd_line_;
+  base::ProcessHandle process_;
+  registry_util::RegistryOverrideManager override_manager_;
+};
+
+}  // namespace
+
+TEST_F(BrowserWatcherTest, ExitCodeWatcherInvalidCmdLineFailsInit) {
+  ExitCodeWatcher watcher(kRegistryPath);
+
+  // An empty command line should fail.
+  EXPECT_FALSE(watcher.ParseArguments(cmd_line_));
+
+  // A non-numeric parent-handle argument should fail.
+  cmd_line_.AppendSwitchASCII("parent-handle", "asdf");
+  EXPECT_FALSE(watcher.ParseArguments(cmd_line_));
+}
+
+TEST_F(BrowserWatcherTest, ExitCodeWatcherInvalidHandleFailsInit) {
+  ExitCodeWatcher watcher(kRegistryPath);
+
+  // A waitable event has a non process-handle.
+  base::WaitableEvent event(false, false);
+
+  // A non-process handle should fail.
+  cmd_line_.AppendSwitchASCII("parent-handle",
+                              base::StringPrintf("%d", event.handle()));
+  EXPECT_FALSE(watcher.ParseArguments(cmd_line_));
+}
+
+TEST_F(BrowserWatcherTest, ExitCodeWatcherNoAccessHandleFailsInit) {
+  ExitCodeWatcher watcher(kRegistryPath);
+
+  // Open a SYNCHRONIZE-only handle to this process.
+  ASSERT_NO_FATAL_FAILURE(OpenSelfWithAccess(SYNCHRONIZE));
+
+  // A process handle with insufficient access should fail.
+  cmd_line_.AppendSwitchASCII("parent-handle",
+                              base::StringPrintf("%d", process_));
+  EXPECT_FALSE(watcher.ParseArguments(cmd_line_));
+}
+
+TEST_F(BrowserWatcherTest, ExitCodeWatcherSucceedsInit) {
+  ExitCodeWatcher watcher(kRegistryPath);
+
+  // Open a handle to this process with sufficient access for the watcher.
+  ASSERT_NO_FATAL_FAILURE(
+      OpenSelfWithAccess(SYNCHRONIZE | PROCESS_QUERY_INFORMATION));
+
+  // A process handle with sufficient access should succeed init.
+  cmd_line_.AppendSwitchASCII("parent-handle",
+                              base::StringPrintf("%d", process_));
+  EXPECT_TRUE(watcher.ParseArguments(cmd_line_));
+
+  ASSERT_EQ(process_, watcher.process());
+
+  // The watcher takes ownership of the handle, make sure it's not
+  // double-closed.
+  process_ = base::kNullProcessHandle;
+}
+
+TEST_F(BrowserWatcherTest, ExitCodeWatcherOnExitedProcess) {
+  ScopedSleeperProcess sleeper;
+  ASSERT_NO_FATAL_FAILURE(sleeper.Launch());
+
+  ExitCodeWatcher watcher(kRegistryPath);
+
+  cmd_line_.AppendSwitchASCII("parent-handle",
+                              base::StringPrintf("%d", sleeper.process()));
+  EXPECT_TRUE(watcher.ParseArguments(cmd_line_));
+  ASSERT_EQ(sleeper.process(), watcher.process());
+
+  // Verify that the watcher wrote a sentinel for the process.
+  VerifyWroteExitCode(sleeper.process_id(), STILL_ACTIVE);
+
+  // Kill the sleeper, and make sure it's exited before we continue.
+  ASSERT_NO_FATAL_FAILURE(sleeper.Kill(kExitCode, true));
+
+  // The watcher took ownership of the handle, make sure it's not
+  // double-closed.
+  sleeper.set_process(base::kNullProcessHandle);

[erikwright (departed), 2014/11/17 18:12:30]

Maybe replace with a nullary "Release()" (or ReleaseHandle,
ReleaseProcessHandle, etc.?).

Also, this ought to go after line 194 (ParseArguments()) as a failure in the
asserts on 195 or 01 would cause double-closes.

Maybe Kill should be a free function taking a HANDLE, in that case.

[Sigurður Ásgeirsson, 2014/11/17 21:27:12]

Went a slightly different way...

+
+  watcher.WaitForExit();
+
+  VerifyWroteExitCode(sleeper.process_id(), kExitCode);
+}
+
+}  // namespace browser_watcher