Port base/watchdog to Linux.

BUG=4632

Review URL: http://codereview.chromium.org/11326
Patch from Pawel Hajdan Jr.

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@6004 0039d316-1c4b-4281-b951-d872f2087c98

5 files changed, 68 insertions, 95 deletions

diff --git a/base/base_lib.scons b/base/base_lib.scons
index b2caa8b..b84d1c1 100644
--- a/base/base_lib.scons
+++ b/base/base_lib.scons
@@ -21,8 +21,8 @@ if env['PLATFORM'] == 'win32':
       ],
   )
 
-# These base files work on *all* platforms; files that don't work
-# cross-platform live below.
+# Some files from this list are not yet ported. They are removed from
+# the list, see code below.
 input_files = [
     'at_exit.cc',
     'base_paths.cc',
@@ -109,14 +109,11 @@ if env['PLATFORM'] in ('posix', 'darwin'):
     'event_recorder.cc',
     'file_version_info.cc',
 
-    # This group all depends on MessageLoop.
-
     # We have an implementation of idle_timer, but it's unclear if we want it
     # yet, so it's commented out for now.  Leave this 'unported'.
     'idle_timer.cc',
 
     'object_watcher.cc',
-    'watchdog.cc',
 
     'resource_util.cc',  # Uses HMODULE, but may be abstractable.
   ]
diff --git a/base/base_unittests.scons b/base/base_unittests.scons
index 37f98ca..833339e 100644
--- a/base/base_unittests.scons
+++ b/base/base_unittests.scons
@@ -114,7 +114,6 @@ if env['PLATFORM'] in ('posix', 'darwin'):
       # yet, so it's commented out for now.  Leave this 'unported'.
       'idletimer_unittest.cc',
 
-      'watchdog_unittest.cc',
       'gfx/native_theme_unittest.cc',
   ]
   for remove in to_be_ported_files:
diff --git a/base/watchdog.cc b/base/watchdog.cc
index b1db70b..0049fec 100644
--- a/base/watchdog.cc
+++ b/base/watchdog.cc
@@ -4,8 +4,8 @@
 
 #include "base/watchdog.h"
 
+#include "base/compiler_specific.h"
 #include "base/platform_thread.h"
-#include "base/string_util.h"
 
 using base::TimeDelta;
 using base::TimeTicks;
@@ -15,42 +15,32 @@ using base::TimeTicks;
 
 // Start thread running in a Disarmed state.
 Watchdog::Watchdog(const TimeDelta& duration,
-                   const std::wstring& thread_watched_name,
+                   const std::string& thread_watched_name,
                    bool enabled)
-  : lock_(),
+  : init_successful_(false),
+    lock_(),
     condition_variable_(&lock_),
     state_(DISARMED),
-    duration_(duration),
     thread_watched_name_(thread_watched_name),
-    handle_(NULL),
-    thread_id_(0) {
+    ALLOW_THIS_IN_INITIALIZER_LIST(delegate_(this, duration)) {
   if (!enabled)
     return;  // Don't start thread, or doing anything really.
-  handle_ = CreateThread(NULL,  // security
-                         0,    // Default stack size.
-                         Watchdog::ThreadStart,
-                         reinterpret_cast<void*>(this),
-                         CREATE_SUSPENDED,
-                         &thread_id_);
-  DCHECK(NULL != handle_);
-  if (NULL == handle_)
-    return ;
-  ResumeThread(handle_);  // WINAPI call.
+  init_successful_ = PlatformThread::Create(0,  // Default stack size.
+                                            &delegate_,
+                                            &handle_);
+  DCHECK(init_successful_);
 }
 
 // Notify watchdog thread, and wait for it to finish up.
 Watchdog::~Watchdog() {
-  if (NULL == handle_)
+  if (!init_successful_)
     return;
   {
     AutoLock lock(lock_);
     state_ = SHUTDOWN;
   }
   condition_variable_.Signal();
-  DWORD results = WaitForSingleObject(handle_, INFINITE);
-  DCHECK(WAIT_OBJECT_0 == results);
-  CloseHandle(handle_);
-  handle_ = NULL;
+  PlatformThread::Join(handle_);
 }
 
 void Watchdog::Arm() {
@@ -75,8 +65,6 @@ void Watchdog::ArmAtStartTime(const TimeTicks start_time) {
 
 // Disable watchdog so that it won't do anything when time expires.
 void Watchdog::Disarm() {
-  if (NULL == handle_)
-    return;
   AutoLock lock(lock_);
   state_ = DISARMED;
   // We don't need to signal, as the watchdog will eventually wake up, and it
@@ -86,43 +74,39 @@ void Watchdog::Disarm() {
 //------------------------------------------------------------------------------
 // Internal private methods that the watchdog thread uses.
 
-// static
-DWORD __stdcall Watchdog::ThreadStart(void* pThis) {
-  Watchdog* watchdog = reinterpret_cast<Watchdog*>(pThis);
-  return watchdog->Run();
-}
-
-unsigned Watchdog::Run() {
+void Watchdog::ThreadDelegate::ThreadMain() {
   SetThreadName();
   TimeDelta remaining_duration;
   while (1) {
-    AutoLock lock(lock_);
-    while (DISARMED == state_)
-      condition_variable_.Wait();
-    if (SHUTDOWN == state_)
-      return 0;
-    DCHECK(ARMED == state_);
-    remaining_duration = duration_ - (TimeTicks::Now() - start_time_);
+    AutoLock lock(watchdog_->lock_);
+    while (DISARMED == watchdog_->state_)
+      watchdog_->condition_variable_.Wait();
+    if (SHUTDOWN == watchdog_->state_)
+      return;
+    DCHECK(ARMED == watchdog_->state_);
+    remaining_duration = duration_ -
+        (TimeTicks::Now() - watchdog_->start_time_);
     if (remaining_duration.InMilliseconds() > 0) {
       // Spurios wake?  Timer drifts?  Go back to sleep for remaining time.
-      condition_variable_.TimedWait(remaining_duration);
+      watchdog_->condition_variable_.TimedWait(remaining_duration);
     } else {
       // We overslept, so this seems like a real alarm.
       // Watch out for a user that stopped the debugger on a different alarm!
       {
         AutoLock static_lock(static_lock_);
-        if (last_debugged_alarm_time_ > start_time_) {
+        if (last_debugged_alarm_time_ > watchdog_->start_time_) {
           // False alarm: we started our clock before the debugger break (last
           // alarm time).
-          start_time_ += last_debugged_alarm_delay_;
-          if (last_debugged_alarm_time_ > start_time_)
-            state_ = DISARMED;  // Too many alarms must have taken place.
+          watchdog_->start_time_ += last_debugged_alarm_delay_;
+          if (last_debugged_alarm_time_ > watchdog_->start_time_)
+            // Too many alarms must have taken place.
+            watchdog_->state_ = DISARMED;
           continue;
         }
       }
-      state_ = DISARMED;  // Only alarm at most once.
+      watchdog_->state_ = DISARMED;  // Only alarm at most once.
       TimeTicks last_alarm_time = TimeTicks::Now();
-      Alarm();  // Set a break point here to debug on alarms.
+      watchdog_->Alarm();  // Set a break point here to debug on alarms.
       TimeDelta last_alarm_delay = TimeTicks::Now() - last_alarm_time;
       if (last_alarm_delay > TimeDelta::FromMilliseconds(2)) {
         // Ignore race of two alarms/breaks going off at roughly the same time.
@@ -135,9 +119,8 @@ unsigned Watchdog::Run() {
   }
 }
 
-void Watchdog::SetThreadName() const {
-  std::string name = StringPrintf("%s Watchdog",
-                                  WideToASCII(thread_watched_name_).c_str());
+void Watchdog::ThreadDelegate::SetThreadName() const {
+  std::string name = watchdog_->thread_watched_name_ + " Watchdog";
   PlatformThread::SetName(name.c_str());
   DLOG(INFO) << "Watchdog active: " << name;
 }
diff --git a/base/watchdog.h b/base/watchdog.h
index c7e967f..63c0612 100644
--- a/base/watchdog.h
+++ b/base/watchdog.h
@@ -22,15 +22,15 @@
 
 #include "base/condition_variable.h"
 #include "base/lock.h"
+#include "base/platform_thread.h"
 #include "base/time.h"
 
 class Watchdog {
  public:
-  // TODO(JAR)change default arg to required arg after all users have migrated.
   // Constructor specifies how long the Watchdog will wait before alarming.
   Watchdog(const base::TimeDelta& duration,
-           const std::wstring& thread_watched_name,
-           bool enabled = true);
+           const std::string& thread_watched_name,
+           bool enabled);
   virtual ~Watchdog();
 
   // Start timing, and alarm when time expires (unless we're disarm()ed.)
@@ -48,22 +48,29 @@ class Watchdog {
   }
 
  private:
-  enum State {ARMED, DISARMED, SHUTDOWN };
+  class ThreadDelegate : public PlatformThread::Delegate {
+   public:
+    explicit ThreadDelegate(Watchdog* watchdog, const base::TimeDelta& duration)
+      : watchdog_(watchdog), duration_(duration) {
+    }
+    virtual void ThreadMain();
+   private:
+    Watchdog* watchdog_;
+    const base::TimeDelta duration_;  // How long after start_time_ do we alarm?
+
+    void SetThreadName() const;
+  };
 
-  // Windows thread start callback
-  static DWORD WINAPI ThreadStart(void* pThis);
+  enum State {ARMED, DISARMED, SHUTDOWN };
 
-  // Loop and test function for our watchdog thread.
-  unsigned Run();
-  void Watchdog::SetThreadName() const;
+  bool init_successful_;
 
   Lock lock_;  // Mutex for state_.
   ConditionVariable condition_variable_;
   State state_;
-  const base::TimeDelta duration_;  // How long after start_time_ do we alarm?
-  const std::wstring thread_watched_name_;
-  HANDLE handle_;  // Handle for watchdog thread.
-  DWORD thread_id_;  // Also for watchdog thread.
+  const std::string thread_watched_name_;
+  PlatformThreadHandle handle_;
+  ThreadDelegate delegate_;  // Store it, because it must outlive the thread.
 
   base::TimeTicks start_time_;  // Start of epoch, and alarm after duration_.
 
@@ -79,8 +86,7 @@ class Watchdog {
   // How long did we sit on a break in the debugger?
   static base::TimeDelta last_debugged_alarm_delay_;
 
-
-  DISALLOW_EVIL_CONSTRUCTORS(Watchdog);
+  DISALLOW_COPY_AND_ASSIGN(Watchdog);
 };
 
 #endif  // BASE_WATCHDOG_H__
diff --git a/base/watchdog_unittest.cc b/base/watchdog_unittest.cc
index c4a664f..887311a 100644
--- a/base/watchdog_unittest.cc
+++ b/base/watchdog_unittest.cc
@@ -5,9 +5,10 @@
 // Tests for Watchdog class.
 
 #include "base/logging.h"
-#include "base/watchdog.h"
+#include "base/platform_thread.h"
 #include "base/spin_wait.h"
 #include "base/time.h"
+#include "base/watchdog.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 using base::TimeDelta;
@@ -17,12 +18,11 @@ namespace {
 //------------------------------------------------------------------------------
 // Provide a derived class to facilitate testing.
 
-// TODO(JAR): Remove default argument from constructor, and make mandatory.
 class WatchdogCounter : public Watchdog {
  public:
   WatchdogCounter(const TimeDelta& duration,
-                  const std::wstring& thread_watched_name,
-                  bool enabled = true)
+                  const std::string& thread_watched_name,
+                  bool enabled)
       : Watchdog(duration, thread_watched_name, enabled), alarm_counter_(0) {
   }
 
@@ -38,7 +38,7 @@ class WatchdogCounter : public Watchdog {
  private:
   int alarm_counter_;
 
-  DISALLOW_EVIL_CONSTRUCTORS(WatchdogCounter);
+  DISALLOW_COPY_AND_ASSIGN(WatchdogCounter);
 };
 
 class WatchdogTest : public testing::Test {
@@ -50,40 +50,28 @@ class WatchdogTest : public testing::Test {
 
 // Minimal constructor/destructor test.
 TEST(WatchdogTest, StartupShutdownTest) {
-  Watchdog watchdog1(TimeDelta::FromMilliseconds(300), L"Disabled", false);
-  Watchdog watchdog2(TimeDelta::FromMilliseconds(300), L"Enabled", true);
-
-  // The following test is depricated, and should be removed when the
-  // default argument constructor is no longer accepted.
-  Watchdog watchdog3(TimeDelta::FromMilliseconds(300), L"Default");
+  Watchdog watchdog1(TimeDelta::FromMilliseconds(300), "Disabled", false);
+  Watchdog watchdog2(TimeDelta::FromMilliseconds(300), "Enabled", true);
 }
 
 // Test ability to call Arm and Disarm repeatedly.
 TEST(WatchdogTest, ArmDisarmTest) {
-  Watchdog watchdog1(TimeDelta::FromMilliseconds(300), L"Disabled", false);
+  Watchdog watchdog1(TimeDelta::FromMilliseconds(300), "Disabled", false);
   watchdog1.Arm();
   watchdog1.Disarm();
   watchdog1.Arm();
   watchdog1.Disarm();
 
-  Watchdog watchdog2(TimeDelta::FromMilliseconds(300), L"Enabled", true);
+  Watchdog watchdog2(TimeDelta::FromMilliseconds(300), "Enabled", true);
   watchdog2.Arm();
   watchdog2.Disarm();
   watchdog2.Arm();
   watchdog2.Disarm();
-
-  // The following test is depricated, and should be removed when the
-  // default argument constructor is no longer accepted.
-  Watchdog watchdog3(TimeDelta::FromMilliseconds(300), L"Default");
-  watchdog3.Arm();
-  watchdog3.Disarm();
-  watchdog3.Arm();
-  watchdog3.Disarm();
 }
 
 // Make sure a basic alarm fires when the time has expired.
 TEST(WatchdogTest, AlarmTest) {
-  WatchdogCounter watchdog(TimeDelta::FromMilliseconds(10), L"Enabled", true);
+  WatchdogCounter watchdog(TimeDelta::FromMilliseconds(10), "Enabled", true);
   watchdog.Arm();
   SPIN_FOR_TIMEDELTA_OR_UNTIL_TRUE(TimeDelta::FromSeconds(1),
                                    watchdog.alarm_counter() > 0);
@@ -100,21 +88,21 @@ TEST(WatchdogTest, AlarmTest) {
 
 // Make sure a disable alarm does nothing, even if we arm it.
 TEST(WatchdogTest, ConstructorDisabledTest) {
-  WatchdogCounter watchdog(TimeDelta::FromMilliseconds(10), L"Disabled", false);
+  WatchdogCounter watchdog(TimeDelta::FromMilliseconds(10), "Disabled", false);
   watchdog.Arm();
   // Alarm should not fire, as it was disabled.
-  Sleep(500);
+  PlatformThread::Sleep(500);
   EXPECT_EQ(0, watchdog.alarm_counter());
 }
 
 // Make sure Disarming will prevent firing, even after Arming.
 TEST(WatchdogTest, DisarmTest) {
-  WatchdogCounter watchdog(TimeDelta::FromSeconds(1), L"Enabled", true);
+  WatchdogCounter watchdog(TimeDelta::FromSeconds(1), "Enabled", true);
   watchdog.Arm();
-  Sleep(100);  // Don't sleep too long
+  PlatformThread::Sleep(100);  // Don't sleep too long
   watchdog.Disarm();
   // Alarm should not fire.
-  Sleep(1500);
+  PlatformThread::Sleep(1500);
   EXPECT_EQ(0, watchdog.alarm_counter());
 
   // ...but even after disarming, we can still use the alarm...