Cross-platform thread primitives

test/Thread.cpp

 #include <gtest/gtest.h>
 #include <queue>
 #include <vector>
 
 #include "../src/Thread.h"
 
 namespace
 {
 #ifndef WIN32
   void Sleep(const int millis)
   {
       usleep(millis * 1000);
   }
 #endif
 
   class Mock : public AdblockPlus::Thread
   {
   public:
     int timesCalled;
     AdblockPlus::Mutex mutex;
 
     Mock() : timesCalled(0)
     {
     }
 
     void Run()
     {
       Sleep(5);

[Wladimir Palant, 2013/04/04 07:09:00]

Why is this necessary? Seems random.

[Felix Dahlke, 2013/04/04 07:27:40]

See below.

       mutex.Lock();
       timesCalled++;
       mutex.Unlock();
     }
   };
 
   class LockingMock : public AdblockPlus::Thread
   {
   public:
     bool working;
 
-    LockingMock(const std::string& name, std::vector<std::string>& log,
-                AdblockPlus::Mutex& logMutex)
-      : name(name), log(log), logMutex(logMutex)
+    LockingMock(std::vector<std::string>& log, AdblockPlus::Mutex& logMutex)
+      : log(log), logMutex(logMutex)
     {
     }
 
     void Run()
     {
       logMutex.Lock();
-      log.push_back(name);
+      log.push_back("started");
+      Sleep(5);
+      log.push_back("ended");
       logMutex.Unlock();
     }
 
   private:
     const std::string name;
     std::vector<std::string>& log;
     AdblockPlus::Mutex& logMutex;
   };
 
   class Enqueuer : public AdblockPlus::Thread
@@ skipping 42 matching lines @@
     AdblockPlus::Mutex& queueMutex;
     AdblockPlus::ConditionVariable& notEmpty;
   };
 }
 
 TEST(ThreadTest, Run)
 {
   Mock mock;
   ASSERT_EQ(0, mock.timesCalled);
   mock.Start();
   mock.mutex.Lock();

[Wladimir Palant, 2013/04/04 07:09:00]

This should be done before mock.Start(), otherwise the thread might lock the
mutex before you do.

[Felix Dahlke, 2013/04/04 07:27:40]

That's what the 5ms sleep above is for. It's not brilliant, but that way it will
at least test that there's actually a separate thread of execution.

[Wladimir Palant, 2013/04/04 09:26:53]

Oh well :-(

   ASSERT_EQ(0, mock.timesCalled);
   mock.mutex.Unlock();
   mock.Join();
   ASSERT_EQ(1, mock.timesCalled);
 }
 
 TEST(ThreadTest, Mutex)
 {
   std::vector<std::string> log;
   AdblockPlus::Mutex logMutex;
-  LockingMock mock1("mock1", log, logMutex);
-  LockingMock mock2("mock2", log, logMutex);
+  LockingMock mock1(log, logMutex);
+  LockingMock mock2(log, logMutex);
   mock1.Start();
-  Sleep(5);
   mock2.Start();

[Wladimir Palant, 2013/04/04 07:09:00]

This test doesn't make sense - mock1 will already be finished by the time mock2
starts, locking or not. Should LockingMock have Sleep(10) before pushing its
name to the log?

Actually, there are ordering assumptions here regardless - these will be correct
most of the time but there is no guarantee. How about starting both mock1 and
mock2 immediately? They could log "name started" when they start, sleep a bit
and log "name done" before releasing the lock. There will be two valid results:
"mock1 started", "mock1 done", "mock2 started", "mock2 done" and "mock2
started", "mock2 done", "mock1 started", "mock1 done".

[Felix Dahlke, 2013/04/04 07:27:40]

Yeah, that's a much better test. Did that.

   mock1.Join();
   mock2.Join();
-  ASSERT_EQ("mock1", log[0]);
-  ASSERT_EQ("mock2", log[1]);
+  ASSERT_EQ("started", log[0]);
+  ASSERT_EQ("ended", log[1]);
+  ASSERT_EQ("started", log[2]);
+  ASSERT_EQ("ended", log[3]);
 }
 
 TEST(ThreadTest, ConditionVariable)
 {
   std::queue<int> queue;
   AdblockPlus::Mutex queueMutex;
   AdblockPlus::ConditionVariable notEmpty;
   Dequeuer dequeuer(queue, queueMutex, notEmpty);
   Enqueuer enqueuer(queue, queueMutex, notEmpty);
   dequeuer.Start();
   Sleep(5);
   enqueuer.Start();
   enqueuer.Join();
   dequeuer.Join();
   ASSERT_EQ(0, queue.size());

[Wladimir Palant, 2013/04/04 09:26:53]

This fails to compile for me once again, 0u please.

 }