synchronize textheavy demos

c_os/user/MainMenu.cc

@@ -9,6 +9,8 @@
 #include "user/demo/VBEdemo.h"
 
 void print_demo_menu() {
+    kout.lock();
+    kout.clear();
     kout << "Demo Menu, press number to start, k to kill:\n"
          << "1 - Text Demo\n"
          << "2 - PCSPK Demo\n"
@@ -18,10 +20,10 @@ void print_demo_menu() {
          << "6 - Bluescreen Demo\n"
          << "7 - Preemption Demo\n"
          << endl;
+    kout.unlock();
 }
 
 void MainMenu::run() {
-    kout.clear();
     print_demo_menu();
 
     char input = '\0';
@@ -61,8 +63,6 @@ void MainMenu::run() {
         } else if (input == 'k') {
             scheduler.kill(choosen_demo);  // NOTE: If thread exits itself this will throw error
             choosen_demo = NULL;
-
-            kout.clear();
             print_demo_menu();
         }
 

c_os/user/demo/HeapDemo.cc

@@ -11,6 +11,8 @@
 #include "user/demo/HeapDemo.h"
 
 void HeapDemo::run() {
+    kout.lock();
+    kout.clear();
     kout << "HEAP_DEMO ===================================================================" << endl;
 
     /* hier muss Code eingefuegt werden */
@@ -70,6 +72,7 @@ void HeapDemo::run() {
     allocator.dump_free_memory();
 
     kout << "HEAP_DEMO END ===============================================================" << endl;
+    kout.unlock();
 
     scheduler.exit();
 }

c_os/user/demo/PreemptiveThreadDemo.cc

@@ -5,29 +5,24 @@ void PreemptiveLoopThread::run() {
 
     while (true) {
         // Basic synchronization by semaphore
-        sem->p();
+        // NOTE: I placed the semaphore inside the CGA_Stream so multiple demos can synchronize, not
+        //       only this one. This is optional so disruptions can still occur because of preemption
+        kout.lock();
 
-        // Saving + restoring kout position doesn't help much as preemption still occurs,
-        // only LoopThreads are synchronized, so other output will be disturbed sometimes
+        // Saving + restoring kout position doesn't help much as preemption still occurs
         kout.setpos(55, this->id);
         kout << fillw(3) << this->id << fillw(0) << ": " << dec << cnt++ << endl;
 
-        sem->v();
+        kout.unlock();
     }
 }
 
 void PreemptiveThreadDemo::run() {
     kout << "Preemptive Thread Demo" << endl;
-    kout << "Initializing Semaphore" << endl;
-    Semaphore* sem = new Semaphore(1);  // Create this semaphore on the heap as this thread exits itself,
-                                        // so stack allocated objects will be lost
-
-    // TODO: Threads disappear, the fewer loop the faster they vanish
-    //       It seems like this happens with exactly 3 or 4 loopthreads
     Thread* threads[this->number_of_threads];
     kout << "Allocating LoopThreads" << endl;
     for (unsigned int i = 0; i < this->number_of_threads; ++i) {
-        threads[i] = new PreemptiveLoopThread(i, sem);
+        threads[i] = new PreemptiveLoopThread(i);
     }
 
     kout << "Adding threads to ready queue" << endl;

c_os/user/demo/PreemptiveThreadDemo.h

@@ -8,13 +8,13 @@
 class PreemptiveLoopThread : public Thread {
 private:
     int id;
-    Semaphore* sem;
+    // Semaphore* sem;
 
     PreemptiveLoopThread(const PreemptiveLoopThread& copy) = delete;  // Verhindere Kopieren
 
 public:
     // Gibt der Loop einen Stack und eine Id.
-    PreemptiveLoopThread(int i, Semaphore* sem) : id(i), sem(sem) {}
+    PreemptiveLoopThread(int i) : id(i) {}
 
     // Zaehlt einen Zaehler hoch und gibt ihn auf dem Bildschirm aus.
     void run() override;

c_os/user/demo/TextDemo.cc

@@ -14,7 +14,10 @@ void TextDemo::run() {
 
     /* Hier muess Code eingefuegt werden */
 
-    kout << "TextDemo\n" << endl;
+    kout.lock();
+    kout.clear();
+    kout << "TextDemo\n"
+         << endl;
 
     kout << "Attribut (GREEN on WHITE): "
          << white_b << green_f << "GREEN on WHITE" << endl
@@ -34,6 +37,7 @@ void TextDemo::run() {
     }
 
     kout << endl;
+    kout.unlock();
 
     scheduler.exit();
 }