threadtest.cc

程序使用的是在nachos体系架构下完成双向链表的构建

// threadtest.cc 
//	Simple test case for the threads assignment.
//
//	Create two threads, and have them context switch
//	back and forth between themselves by calling Thread::Yield, 
//	to illustratethe inner workings of the thread system.
//
// 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.

#include "copyright.h"
#include "system.h"
#include "dllist.h"
extern void insert(DLList*list,int n);
extern void remove(DLList*list,int n);
extern DLList*list;
extern int mode;
// testnum is set in main.cc
int testnum = 1;

//----------------------------------------------------------------------
// SimpleThread
// 	Loop 5 times, yielding the CPU to another ready thread 
//	each iteration.
//
//	"which" is simply a number identifying the thread, for debugging
//	purposes.
//----------------------------------------------------------------------

void
SimpleThread(int which)
{
    int num;
    
    for (num = 0; num < 1; num++) {
	printf("*** thread %d looped %d times ***\n", which, num);
        if(mode==1){
        remove(list,1);
        //printf("items in the list:");
        list->Print();
        //printf("\n");
        //currentThread->Yield();
       // remove(list,2);
       // list->Print();
       // printf("\n");}
       }
       else if(mode==2||mode==3)
       {
         int *itemPtr;
         printf("thread %d find the location to insert %d\n",which,50+which);
         if(which==0){
         list->SortedInsert(itemPtr,50);
         printf("after thread %d insert %d\n",which,50+which);
         list->Print();}
         else if(which==1){
         list->SortedInsert(itemPtr,51);
         printf("after thread %d insert %d\n",which,50+which);
         list->Print();}
       }
        currentThread->Yield();
    }
}

//----------------------------------------------------------------------
// ThreadTest1
// 	Set up a ping-pong between two threads, by forking a thread 
//	to call SimpleThread, and then calling SimpleThread ourselves.
//----------------------------------------------------------------------

void
ThreadTest1()
{
    DEBUG('t', "Entering ThreadTest1");

    Thread *t = new Thread("forked thread");

    t->Fork(SimpleThread, 1);
    SimpleThread(0);
}

//----------------------------------------------------------------------
// ThreadTest
// 	Invoke a test routine.
//----------------------------------------------------------------------

void
ThreadTest()
{
    switch (testnum) {
    case 1:
	ThreadTest1();
	break;
    default:
	printf("No test specified.\n");
	break;
    }
}