Class Semaphore

Kernel/include/lock.h:51–83

};

class Semaphore : public Scheduler::GenericThreadBlocker{
protected:
    lock_t value = 0;
    lock_t blockedLock = 0;
public:
    Semaphore(int val){
        value = val;
    }

    void SetValue(int val){
        value = val;
    }

    lock_t GetValue(){
        return value;
    }

    void Wait();

    void WaitTimeout(long timeout);

    inline void Signal(){
        __sync_fetch_and_add(&value, 1);

        if(blocked.get_length() > 0){
            acquireLock(&blockedLock);
            if(blocked.get_length() > 0){
                Scheduler::UnblockThread(blocked.remove_at(0));
            }
            releaseLock(&blockedLock);
        }
    }
};