init: init nachos hw01, should pass jenkins os_group_20_hw job but fail on os_group_20_ta job

code/threads/synchlist.h

@@ -0,0 +1,51 @@
+// synchlist.h 
+//	Data structures for synchronized access to a list.
+//
+//	Identical interface to List, except accesses are synchronized.
+//
+// Copyright (c) 1992-1996 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 structures
+
+template <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 RemoveFront();		// remove the first item from the front of
+				// the list, waiting if the list is empty
+
+    void Apply(void (*f)(T)); // apply function to all elements in list
+
+    void SelfTest(T value);	// test the SynchList implementation
+    
+  private:
+    List<T> *list;		// the list of things
+    Lock *lock;			// enforce mutual exclusive access to the list
+    Condition *listEmpty;	// wait in Remove if the list is empty
+    
+    // these are only to assist SelfTest()
+    SynchList<T> *selfTestPing;
+    static void SelfTestHelper(void* data);
+};
+
+#include "synchlist.cc"
+
+#endif // SYNCHLIST_H