Anpassungen Semaphor

P5/Main.cpp

@@ -1,41 +1,48 @@
 #include <iostream>
 #include <thread>
 #include <mutex>
-#include "Semaphore.h"
+#include "Semaphor.h"
 #include <process.h>
 
 using namespace std;
 
 // Thread T1 - Schreibt alle Kleinbuchstaben des Alphabets
-void thread1() {
-    for (char c = 'a'; c <= 'z'; ++c) {
+void thread1()
+{
+    for (char c = 'a'; c <= 'z'; ++c)
+    {
         cout << c << ' ';
     }
     cout << endl;
 }
 
 // Thread T2 - Schreibt alle natürlichen Zahlen von 0 bis 32
-void thread2() {
-    for (int i = 0; i <= 32; ++i) {
+void thread2()
+{
+    for (int i = 0; i <= 32; ++i)
+    {
         cout << i << ' ';
     }
     cout << endl;
 }
 
 // Thread T3 - Schreibt alle Großbuchstaben des Alphabets
-void thread3() {
-    for (char c = 'A'; c <= 'Z'; ++c) {
+void thread3()
+{
+    for (char c = 'A'; c <= 'Z'; ++c)
+    {
         cout << c << ' ';
     }
     cout << endl;
 }
 
-void asynch_init(){
+void asynch_init()
+{
     // Start der Threads
     thread t1(thread1);
     thread t2(thread2);
     thread t3(thread3);
-    
+
     // Warten auf die Beendigung der Threads
     t1.join();
     t2.join();
@@ -44,10 +51,12 @@ void asynch_init(){
 
 mutex mtx;
 
-void mutexThread1() {
+void mutexThread1()
+{
     mtx.lock();
 
-    for (char ch = 'a'; ch <= 'z'; ch++) {
+    for (char ch = 'a'; ch <= 'z'; ch++)
+    {
         cout << ch << " ";
     }
     cout << endl;
@@ -55,11 +64,13 @@ void mutexThread1() {
     mtx.unlock();
 }
 
-void mutexThread2() {
-   
+void mutexThread2()
+{
+
     mtx.lock();
 
-    for (int i = 0; i < 33; i++) {
+    for (int i = 0; i < 33; i++)
+    {
         cout << i << " ";
     }
     cout << endl;
@@ -67,10 +78,12 @@ void mutexThread2() {
     mtx.unlock();
 }
 
-void mutexThread3() {
+void mutexThread3()
+{
     mtx.lock();
 
-    for (char ch = 'A'; ch <= 'Z'; ch++) {
+    for (char ch = 'A'; ch <= 'Z'; ch++)
+    {
         cout << ch << " ";
     }
     cout << endl;
@@ -78,56 +91,63 @@ void mutexThread3() {
     mtx.unlock();
 }
 
-void mutex_init() {
+void mutex_init()
+{
     thread t1(mutexThread1); // mutexThread1 is running
     thread t2(mutexThread2); // mutexThread2 is running
     thread t3(mutexThread3); // mutexThread3 is running
-    t1.join();  // main thread waits for t1 to finish
-    t2.join();  // main thread waits for t2 to finish
-    t3.join();  // main thread waits for t3 to finish
+    t1.join();               // main thread waits for t1 to finish
+    t2.join();               // main thread waits for t2 to finish
+    t3.join();               // main thread waits for t3 to finish
 }
 
-Semaphore semaphore;
+Semaphor semaphor(1);
 
-void semaphoreThread1() {
-    semaphore.wait();
-    for (char ch = 'a'; ch <= 'z'; ch++) {
+void semaphoreThread1()
+{
+    semaphor.acquire();
+    for (char ch = 'a'; ch <= 'z'; ch++)
+    {
         cout << ch << " ";
     }
     cout << endl;
-    semaphore.post();
+    semaphor.release();
 }
 
-void semaphoreThread2() {
-    semaphore.wait();
-    for (int i = 0; i < 33; i++) {
+void semaphoreThread2()
+{
+    semaphor.acquire();
+    for (int i = 0; i < 33; i++)
+    {
         cout << i << " ";
     }
     cout << endl;
-    semaphore.post();
-
+    semaphor.release();
 }
 
-void semaphoreThread3() {
-    semaphore.wait();
-    for (char ch = 'A'; ch <= 'Z'; ch++) {
+void semaphoreThread3()
+{
+    semaphor.acquire();
+    for (char ch = 'A'; ch <= 'Z'; ch++)
+    {
         cout << ch << " ";
     }
     cout << endl;
-    semaphore.post();
-
+    semaphor.release();
 }
 
-void semaphore_init() {
+void semaphore_init()
+{
     thread t1(semaphoreThread1); // thread1 is running
     thread t2(semaphoreThread2); // thread2 is running
     thread t3(semaphoreThread3); // thread3 is running
-    t1.join();  // main thread waits for t1 to finish
-    t2.join();  // main thread waits for t2 to finish
-    t3.join();  // main thread waits for t3 to finish
+    t1.join();                   // main thread waits for t1 to finish
+    t2.join();                   // main thread waits for t2 to finish
+    t3.join();                   // main thread waits for t3 to finish
 }
 
-int main() {
+int main()
+{
 
     cout << "Asynch" << endl;
     asynch_init();
@@ -137,6 +157,6 @@ int main() {
 
     cout << "Semaphore" << endl;
     semaphore_init();
-    
+
     return 0;
 }

P5/Semaphor.h

@@ -0,0 +1,32 @@
+#include <mutex>
+#include <condition_variable>
+#include <queue>
+
+class Semaphor
+{
+private:
+    int count;
+    std::mutex mtx;
+    std::condition_variable cond;
+    std::queue<std::thread::id> wait_queue; // Beispielhafte Warteschlange
+
+public:
+    Semaphor(int i) : count(i) {}
+
+    void acquire()
+    {
+        std::unique_lock<std::mutex> lock(mtx);
+        while (count == 0)
+        { // Solange keine Ressourcen verfügbar sind, warten
+            cond.wait(lock);
+        }
+        count--; // Ressource belegen
+    }
+
+    void release()
+    {
+        std::unique_lock<std::mutex> lock(mtx);
+        count++;           // Ressource freigeben
+        cond.notify_one(); // Einen wartenden Thread aufwecken
+    }
+};

P5/Semaphore.h

@@ -1,52 +0,0 @@
-#ifndef MULTITHREADING_SEMAPHORE_H
-#define MULTITHREADING_SEMAPHORE_H
-#include <mutex>
-#include <condition_variable>
-
-class Semaphore {
-private:
-    std::mutex mtx;
-    std::condition_variable cv;
-    int signal;
-
-public:
-    Semaphore(int signal_ = 1) : signal(signal_) { }
-
-    /**
-     * atomic function
-     */
-    
-    inline void post() {
-        std::unique_lock<std::mutex> lock(mtx);
-        signal++;
-
-        //notify the waiting thread
-        //unblock(), waiting queue it not empty, wake up call thread from waiting queue
-
-        cv.notify_one();
-
-        /** Notify one
-         * Unblocks one of the threads currently waiting for this condition.
-         * If no threads are waiting, the function does nothing.
-         */
-    }
-
-    /**
-     * atomic function
-     */
-
-    inline void wait() {
-        std::unique_lock<std::mutex> lock(mtx);
-        if (signal <= 0) {
-
-            // wait on the mutex until notify is called
-            // block(), put this thread into waiting status, sleep and put in waiting queue
-            cv.wait(lock);
-        }
-        if (signal > 0) {
-            signal--;
-        }
-    }
-
-};
-#endif //MULTITHREADING_SEMAPHORE_H