synch-sleep.h

nachos下线程与同步的实验

#include "copyright.h"
#include "thread.h"
#include "list.h"
#include "system.h"

class Lock
{
      public:
             Lock(char* debugName);  //initialize lock be FREE
             ~Lock();  //析构函数
             char* getName() { return name; } //debugging assist
             
             void Acquire(); //wait until the lock is FREE, then set it to BUSY
             void Release(); //set lock to be FREE, waking up a thread waiting
                             //in Acquire if necessary
             
             bool isHeldByCurrentThread();  // true if the current thread
             // holds this lock.  Useful for checking in Release, and in
             // Condition variable ops below
             
      private:
              char* name;
              Thread *HoldThread;
              bool Hold;
              List *queue;
};

class Condition
{
      public:
             Condition(char* debugName); //initialize condition to "no one waiting"
             ~Condition();　//析构函数 
             char* getName() { return name; }
             
             void Wait(Lock *conditionLock);
             //release the lock, relinquish the CPU until signaled,then re-acquire the lock
             void Signal(Lock *conditionLock); 
             //wake up a thread, if there are any waiting on the condition
             void Broadcast(Lock *conditionLock);
             //wake up all threads waiting on the condition
      private:
              char* name;
              List *queue;
};