// synchlist.h //	Data structures for synchronized access to a list.////	Implemented by surrounding the List abstraction//	with synchronization routines.//// Copyright (c) 1992-1993 The Regents of the University of California.// All rights reserved.  See copyright.h for copyright notice and limitation // of liability and disclaimer of warranty provisions.#ifndef SYNCHLIST_H#define SYNCHLIST_H#include "copyright.h"#include "list.h"#include "synch.h"// The following class defines a "synchronized list" -- a list for which:// these constraints hold://	1. Threads trying to remove an item from a list will//	wait until the list has an element on it.//	2. One thread at a time can access list data structurestemplate <class T>class SynchList {  public:    SynchList();		// initialize a synchronized list    ~SynchList();		// de-allocate a synchronized list    void Append(T item);	// append item to the end of the list,				// and wake up any thread waiting in remove    T Remove();			// remove the first item from the front of				// the list, waiting if the list is empty				// apply function to every item in the list    void Mapcar(VoidFunctionPtr func);  private:    List<T> *list;		// the unsynchronized list    Lock *lock;			// enforce mutual exclusive access to the list    Condition *listEmpty;	// wait in Remove if the list is empty};#include "synchlist.cc"#endif // SYNCHLIST_H