thead: 彻底去掉 QThread

已知问题：刚启动UI就自动下了2子。

src/aithread.cpp

@@ -36,7 +36,7 @@ Value MTDF(Position *pos, Sanmill::Stack<Position> &ss, Value firstguess, Depth
 
 AiThread::AiThread(int color, QObject *parent) :
     stdThread(&AiThread::idle_loop, this),
-    QThread(parent),
+    QObject(parent),
     timeLimit(3600)
 {
     this->us = color;
@@ -172,7 +172,7 @@ void AiThread::idle_loop()    // idle_loop()
 
 void AiThread::act()
 {
-    if (isFinished() || !isRunning())
+    if (exit|| !searching)
         return;
 
     std::lock_guard<std::mutex> lk(mutex);

src/aithread.h

@@ -22,7 +22,6 @@
 
 #include <condition_variable>
 #include <mutex>
-#include <QThread>
 #include <QTimer>
 #include "position.h"
 #include "search.h"
@@ -32,11 +31,11 @@
 #include "position.h"
 #include "thread_win32_osx.h"
 
-class AiThread : public QThread
+class AiThread : public QObject
 {
     Q_OBJECT
 
-private:
+public:
     std::mutex mutex;
     std::condition_variable cv;
     bool exit = false, searching = true; // Set before starting std::thread

src/ui/qt/gamecontroller.cpp

@@ -352,10 +352,10 @@ void GameController::setEngine(int color, bool arg)
 
     if (arg) {
         aiThread[color]->setAi(&position);
-        if (aiThread[color]->isRunning())
+        if (aiThread[color]->searching)
             aiThread[color]->start_searching();
         else
-            aiThread[color]->start();
+            aiThread[color]->start_searching();
     } else {
         aiThread[color]->start_searching();
     }

src/ui/qt/gamecontroller.h

@@ -268,11 +268,11 @@ public slots:
     void startAiThreads()
     {
         if (isAiPlayer[BLACK]) {
-            aiThread[BLACK]->start();
+            aiThread[BLACK]->start_searching();
         }
 
         if (isAiPlayer[WHITE]) {
-            aiThread[WHITE]->start();
+            aiThread[WHITE]->start_searching();
         }
     }
 
@@ -280,11 +280,11 @@ public slots:
     {
         if (isAiPlayer[BLACK]) {
             aiThread[BLACK]->start_searching();
-            aiThread[BLACK]->wait();
+            aiThread[BLACK]->wait_for_search_finished();
         }
         if (isAiPlayer[WHITE]) {
             aiThread[WHITE]->start_searching();
-            aiThread[WHITE]->wait();
+            aiThread[WHITE]->wait_for_search_finished();
         }
     }
 
@@ -296,8 +296,8 @@ public slots:
 
     void waitThreads()
     {
-        aiThread[BLACK]->wait();
-        aiThread[WHITE]->wait();
+        aiThread[BLACK]->wait_for_search_finished();
+        aiThread[WHITE]->wait_for_search_finished();
     }
 
     void stopAndWaitThreads()