C语言模拟CPU调度C语言模拟CPU调度CPU在处理多个进程时，要根据各种情况对处理的进程进行调度。

这其中就包括对各个进程优先级的处理，和调度算法的处理。

下面这个C语言程序，是我在大学期间学习《操作系统》课程的CPU调度时编写的，模拟了CPU的两种调度模式和各种模式所对应的多种调度算法。

为了模拟得更为形象，采用了图形屏幕输出。

#include<stdlib.h>#include<stdio.h>#include<conio.h>#include<graphics.h>#include<math.h>#include<dos.h>#define NULL 0/*-----------------------------------------------------------------*/ struct event /*事件结点结构*/{int evtype; /*1：进程产生。

2：进程执行。

3：激活阻塞进程。

4：进程执行完5:进程阻塞* 6:返回事件*/int pnum; /*执行该事件的进程号*/int t; /*事件发生的时间*/int ifblock; /*如果是执行事件标准其有无阻塞，其它事件时无定义*/struct event *next;};struct process /*进程结点结构*/{int pnum; /*进程号*/int plong; /*进程长度*/int prior; /*进程优先级*/int blocknum; /*进程当前的阻塞数*/int runtime; /*执行次数*/struct process *next;};struct headnod /*队列头结点结构*/{struct process *head; /*队列头*/int totalpro; /*队列中的进程数*/struct process *tail; /*队列尾*/};/*============================================ =====================*/int Mode,Algorithm; /*选择的调度模式和算法*/ struct event *evhead; /*事件链表的头结点*/struct headnod *ready,*block; /*就绪队列、阻塞队列的头结点*/main(){int gdriver,gmode;struct process *runpro=NULL; /*当前正在执行的进程*/ struct process *wakepro; /*当前被唤醒的进程*/ struct process *newpro; /*新建进程*/int busy=0; /*标志cpu状态*/menu(); /*选择调度模式和算法的菜单*/gdriver=DETECT;initgraph(&gdriver, &gmode, "");setbkcolor(LIGHTBLUE);cleardevice();welcome(); /*显示欢迎屏幕*/start(); /*初始化*/while(evhead!=NULL){switch(evhead->evtype){case 1: /*产生新进程并在就绪队列中排队*/{randomize();newpro=(struct process *)malloc(sizeof(struct process));newpro->pnum=evhead->pnum;newpro->plong=rand()%3+1;if((Mode==2)&&(Algorithm==2))newpro->prior=rand()%3+1;elsenewpro->prior=0; /*优先级相等*/if((Mode==2)&&(Algorithm==1)){newpro->runtime=newpro->plong+1;newpro->blocknum=rand()%2;}else{newpro->blocknum=rand()%3;newpro->runtime=1;}newpro->next=NULL;drawcreate(newpro); /*画出产生一个新进程*/Orderp(1,newpro);drawQ(1);sleep(1);if(ready->head==newpro){if(busy==0)Runevent();elseif((Mode==2)&&(Algorithm==2)&&(newp ro->prior>runpro->prior)){Interupt(runpro);returnev(runpro);}}}break;case 2: /*执行事件*/ {runpro=ready->head;ready->head=ready->head->next; runpro->next=NULL;ready->totalpro--;busy=1;Run(runpro); /*画进入cpu*/ drawQ(1);sleep(1);if(evhead->ifblock==1)blockev(runpro);else{runpro->runtime--;if(runpro->runtime==0)overev(runpro); /*产生结束事件*/elsereturnev(runpro);}}break;case 3: /*激活事件*/ {wakepro=block->head;block->head=block->head->next;wakepro->next=NULL;block->totalpro--;wakeup(wakepro);/*移动激活进程*/if(block->totalpro!=0){drawQ(2);sleep(1);}Orderp(1,wakepro);drawQ(1);sleep(1);if(ready->head==wakepro){if(busy==0)Runevent();elseif((Mode==2)&&(Algorithm==2)&&(wake pro->prior>runpro->prior)){Interupt(runpro);returnev(runpro);}}wakepro=NULL;if(block->totalpro!=0)wakeupev();}break;case 4: /*结束事件*/{over(runpro);runpro=NULL;busy=0;if(ready->totalpro!=0)Runevent();}break;case 5: /*阻塞事件*/ {blocked(runpro);busy=0;if(ready->totalpro!=0)Runevent();Orderp(2,runpro);drawQ(2);sleep(1);if(block->head==runpro)wakeupev();runpro=NULL;}break;case 6: /*返回事件*/ {returnwait(runpro); /*画出返回*/ busy=0;Orderp(1,runpro);runpro=NULL;drawQ(1);sleep(1);Runevent();}break;}evhead=evhead->next;}setcolor(LIGHTRED);settextstyle(1,0,0);setusercharsize(1, 1, 2, 1);outtextxy(290,340,"END!");setcolor(15);settextstyle(1,0,1);outtextxy(105,420,"Author : ZHOUWUBO CLASS : 01-1 NO.17");getch();getch();closegraph();}/*============================================ =====================*/menu() /*选择菜单*/{char wrong;textbackground(LIGHTBLUE);clrscr();window(20,3,60,23);textbackground(LIGHTRED);textcolor(YELLOW);clrscr();gotoy(2,2);cprintf("Please select the Scheduling Mode:");gotoxy(5,3);cprintf("1.Non-Preemptive");gotoxy(5,4);cprintf("2.Preemptive");gotoxy(7,5);cprintf(">> ");cscanf("%d",&Mode);switch(Mode){case 1:{gotoxy(2,7);cprintf("Please select the Scheduling Algorithm:");gotoxy(5,8);cprintf("1.FCFS");gotoxy(5,9);cprintf("2.SPF");gotoxy(7,10);cprintf(">> ");cscanf("%d",&Algorithm);if((Algorithm!=1)&&(Algorithm!=2)){gotoxy(2,12);cprintf("Your select is wrong! Run once again!");scanf("%c",&wrong);}break;}case 2:{gotoxy(2,7);cprintf("Please select the Scheduling Algorithm:");gotoxy(5,8);cprintf("1.Round Robin");gotoxy(5,9);cprintf("2.Priority");gotoxy(7,10);cprintf(">> ");cscanf("%d",&Algorithm);if((Algorithm!=1)&&(Algorithm!=2)){gotoxy(2,12);cprintf("Your select is wrong! Run once again!");scanf("%c",&wrong);}break;}default:{gotoxy(2,7);cprintf("Your select is wrong! Run once again!"); scanf("%c",&wrong);}}/*-----------------------------------------------------------------*/ welcome() /*显示欢迎屏幕*/{int i;setcolor(14);outtextxy(45,178,"create");outtextxy(40,188,"process");outtextxy(555,210,"Finish");line(100,204,170,204);line(170,204,160,199);line(160,199,165,204);line(100,226,170,226);line(170,226,160,231);line(160,231,165,226);rectangle(370,40,420,60);rectangle(425,40,475,60);rectangle(480,40,530,60);rectangle(535,40,588,60);setcolor(LIGHTRED);if((Mode==1)&&(Algorithm==1))int arw[8]={395,62,385,77,405,77,395,62};setlinestyle(0, 0, 3);drawpoly(4,arw);}if((Mode==1)&&(Algorithm==2)) {int arw[8]={450,62,440,77,460,77,450,62};setlinestyle(0, 0, 3);drawpoly(4,arw);}if((Mode==2)&&(Algorithm==1)) {int arw[8]={505,62,495,77,515,77,505,62};setlinestyle(0, 0, 3);drawpoly(4,arw);}if((Mode==2)&&(Algorithm==2)) {int arw[8]={561,62,551,77,571,77,561,62};setlinestyle(0, 0, 3);drawpoly(4,arw);setlinestyle(0, 0, 1);settextstyle(2,0,7);outtextxy(373,40,"FCFS");outtextxy(434,40,"SPF");outtextxy(495,40,"RR");settextstyle(2,0,5);outtextxy(537,42,"Priorty"); settextstyle(1,0,0);setusercharsize(1, 1, 2, 1);outtextxy(82,18, "CPU SCHEDULING"); outtextxy(280,360,"start!");setcolor(14);line(220,204,230,204);line(230,204,230,200);line(230,200,380,200);line(380,200,380,204);line(380,204,390,204);line(390,204,424,180);line(424,180,424,170);line(456,180,456,100);line(456,100,180,100);line(180,204,175,194);line(175,194,180,199);line(456,180,490,204);line(490,204,510,204); settextstyle(1,0,1);outtextxy(275,180,"READY"); line(220,226,230,226);line(230,226,230,230);line(230,230,380,230);line(380,230,380,226);line(380,226,390,226);line(390,226,424,250);line(424,250,424,260);line(456,250,456,330);line(456,330,410,330);line(410,330,410,334);line(410,334,260,334);line(260,334,260,330);line(260,330,180,330);line(180,330,180,226);line(180,226,175,236);line(420,308,410,308);line(410,308,410,304);line(410,304,260,304);line(260,304,260,308);line(260,308,250,308);line(456,250,490,226);line(490,226,510,226);outtextxy(305,285,"BLOCK");circle(440,215,30);sleep(2);setcolor(LIGHTBLUE);for(i=0;i<=43;i++){line(280+i,360,280+i,420);line(365-i,360,365-i,420);delay(5000);}}/*-----------------------------------------------------------------*/ start() /*初始化*/{int i;int t;struct event *p1,*p2;p1=(struct event *)malloc(sizeof(struct event));p1->evtype=1;p1->pnum=1;p1->t=0;p1->ifblock=0; /*在进程产生事件中无意义*/ p1->next=NULL;t=p1->t;evhead=p1;randomize();for(i=2;i<=5;i++){p2=(struct event *)malloc(sizeof(struct event)); p2->evtype=1;p2->pnum=i;p2->t=t+rand()%2+1;p2->ifblock=0;p2->next=NULL;t=p2->t;p1->next=p2;p1=p1->next;}ready=(struct headnod*)malloc(sizeof(struct headnod));ready->head=NULL;ready->totalpro=0;ready->tail=NULL;block=(struct headnod*)malloc(sizeof(struct headnod));block->head=NULL;block->totalpro=0;block->tail=NULL;}/*-----------------------------------------------------------------*/ drawcreate(struct process *p) /*画出进程的产生过程*/ {void *buf;int i,size;setfillstyle(1,p->pnum);bar(56,206,55+10*p->plong,224);size=imagesize(55,205,56+10*p->plong,225);buf=malloc(size);getimage(55,205,56+10*p->plong,225,buf);for(i=0; i<134; i++){putimage(55+i,205,buf,COPY_PUT);delay(3500);}free(buf);}/*-----------------------------------------------------------------*/ Orderp(int flag,struct process *p)/*1：就绪队列排队2：阻塞队列排队*/{struct process *q;if(flag==1) /*就绪队列*/{if(ready->totalpro==0){ready->head=p;ready->tail=p;ready->totalpro++;}else{if((Mode==1)&&(Algorithm==1)) /*FCFS*/{ready->tail->next=p;ready->tail=ready->tail->next;ready->totalpro++;}if((Mode==1)&&(Algorithm==2)) /*短进程优先*/{if(p->plong<ready->head->plong) /*长度小于当前队头*/{p->next=ready->head;ready->head=p;ready->totalpro++;}else /*长度大于当前队头*/{q=ready->head;while(q->next!=NULL){if(p->plong<q->next->plong) {p->next=q->next;q->next=p;ready->totalpro++;break;}elseq=q->next;}if(q->next==NULL){q->next=p;ready->totalpro++;ready->tail=p;}}}if((Mode==2)&&(Algorithm==1)) /*时间片轮转*/{ready->tail->next=p;ready->tail=ready->tail->next;ready->totalpro++;if((Mode==2)&&(Algorithm==2)) /*抢占优先级*/{if(p->prior>ready->head->prior) /*优先级高于当前队头*/{p->next=ready->head;ready->head=p;ready->totalpro++;}else /*优先级低于当前队头*/{q=ready->head;while(q->next!=NULL){if(p->prior>q->next->prior) {p->next=q->next;q->next=p;ready->totalpro++;break;elseq=q->next;}if(q->next==NULL) {q->next=p;ready->totalpro++;ready->tail=p;}}}}}if(flag==2) /*阻塞队列*/{if(block->totalpro==0){block->head=p;block->totalpro++;block->tail=p;}else{block->tail->next=p;block->tail=block->tail->next;block->totalpro++;}}}/*-----------------------------------------------------------------*/ drawQ(int flag) /*画出队列，flag=1:就绪队列，flag=2:阻塞队列*/{int i,j;struct process *p;if(flag==1){setcolor(LIGHTBLUE);for(i=0;i<=150;i++)line(230+i,205,230+i,225);for(i=0;i<=30;i++)line(189+i,203,189+i,227);p=ready->head;j=379;for(i=1;i<=ready->totalpro;i++) {setfillstyle(1,p->pnum);bar(j,206,j-10*p->plong+1,224);j=j-10*p->plong-1;p=p->next;}}if(flag==2){setcolor(LIGHTBLUE);for(i=0;i<=150;i++)line(260+i,309,260+i,39);for(i=0;i<=30;i++)line(420+i,308,420+i,329);p=block->head;j=261;for(i=1;i<=block->totalpro;i++) {setfillstyle(1,p->pnum);bar(j,309,j+10*p->plong-1,328);j=j+10*p->plong+1;p=p->next;}}}/*-----------------------------------------------------------------*/ Runevent() /*产生执行事件*/{struct event *p1;struct process *p;p=ready->head;randomize();p1=(struct event *)malloc(sizeof(struct event));p1->evtype=2;p1->pnum=p->pnum;p1->t=evhead->t;if(p->blocknum!=0){p1->ifblock=rand()%2;if(p1->ifblock==1)p->blocknum--;}elsep1->ifblock=0;p1->next=NULL;Orderev(p1);}/*-----------------------------------------------------------------*/ Interupt(struct process *p) /*中断当前正在执行的进程*/ {struct event *q1,*q2;if(evhead->next==NULL){if(evhead->evtype==4)p->runtime++;evhead=NULL;}else{q1=evhead->next;q2=evhead;}while(q1!=NULL){if(q1->pnum==p->pnum){if(q1->evtype==4)p->runtime++;q2->next=q1->next;break;}else{q2=q1;q1=q1->next;}}}/*-----------------------------------------------------------------*/ Orderev(struct event *q) /*在事件链表中插入结点*/ {struct event *p;p=evhead;while(p->next!=NULL){if(q->t<p->next->t){q->next=p->next;p->next=q;break;}elsep=p->next;}if(p->next==NULL)p->next=q;}/*----------------------------------------------------------------*/ blockev(struct process *p) /*产生阻塞事件*/{struct event *q;randomize();q=(struct event *)malloc(sizeof(struct event));q->evtype=5;q->pnum=p->pnum;q->t=evhead->t+rand()%4+2;q->ifblock=0;q->next=NULL;Orderev(q);}/*-----------------------------------------------------------------*/ blocked(struct process *p) /*画出阻塞过程*/{int i,size;void *buf;setcolor(LIGHTBLUE);for(i=1;i<=28;i++)circle(440,215,i);setfillstyle(1,p->pnum);bar(426,251,426+10*p->plong-2,269);size=imagesize(425,250,426+10*p->plong-1,270);buf=malloc(size);getimage(425,250,426+10*p->plong-1,270,buf);for(i=0; i<59; i++){putimage(425,250+i,buf,COPY_PUT);delay(3500);}for(i=0;i<5;i++){putimage(425-i,308,buf,COPY_PUT);delay(3500);}free(buf);}/*-----------------------------------------------------------------*/ wakeupev() /*产生唤醒事件*/{struct event *q;struct process *p;p=block->head;randomize();q=(struct event *)malloc(sizeof(struct event));q->evtype=3;q->pnum=p->pnum;q->t=evhead->t+rand()%3+4;q->ifblock=0; /*此时无意义*/q->next=NULL;Orderev(q);}/*-----------------------------------------------------------------*/ Run(struct process *p) /*画出执行*/int i,size;void *buf;size=imagesize(380,205,380-10*p->plong-1,225);buf=malloc(size);getimage(380,205,380-10*p->plong-1,225,buf);for(i=0; i<29; i++){putimage(380-10*p->plong-1+i,205,buf,COPY_PUT);delay(3500);}setcolor(LIGHTBLUE);for(i=0;i<29;i++)line(380+i,205,380+i,225);setcolor(p->pnum);for(i=1;i<=28;i++)circle(440,215,i);free(buf);}/*-----------------------------------------------------------------*/ overev(struct process *p) /*产生结束事件*/struct event *q;randomize();q=(struct event *)malloc(sizeof(struct event));q->evtype=4;q->pnum=p->pnum;if((Mode==2)&&(Algorithm==1))q->t=evhead->t+2; /*时间片为2*/elseq->t=evhead->t+3*(p->plong);/*时间由进程长度确定*/q->ifblock=0;q->next=NULL;Orderev(q);}/*-----------------------------------------------------------------*/ returnev(struct process *p) /*产生返回事件*/{struct event *q;randomize();q=(struct event *)malloc(sizeof(struct event));q->evtype=6;q->pnum=p->pnum;if((Mode==2)&&(Algorithm==2))q->t=evhead->t;elseq->t=evhead->t+2; /*时间片为2*/q->ifblock=0;q->next=NULL;Orderev(q);}/*-----------------------------------------------------------------*/ wakeup(struct process *p)/*画出唤醒过程*/{int i,size;void *buf;size=imagesize(260,309,261+10*p->plong,329);buf=malloc(size);getimage(260,309,261+10*p->plong,329,buf);for(i=0; i<72; i++){putimage(260-i,309,buf,COPY_PUT);delay(3500);}for(i=0;i<104;i++){putimage(189,309-i,buf,COPY_PUT);delay(3500);}free(buf);}/*-----------------------------------------------------------------*/ returnwait(struct process *p)/*画出返回过程*/{int i,size;void *buf;setcolor(LIGHTBLUE);for(i=1;i<=28;i++)circle(440,215,i);setfillstyle(1,p->pnum);bar(426,161,426+10*p->plong-2,179);size=imagesize(425,160,426+10*p->plong-1,180);buf=malloc(size);getimage(425,160,426+10*p->plong-1,180,buf);for(i=0; i<59; i++){putimage(425,160-i,buf,COPY_PUT);delay(3500);}for(i=0;i<237;i++){putimage(425-i,101,buf,COPY_PUT);delay(3500);}for(i=0;i<105;i++){putimage(189,101+i,buf,COPY_PUT);delay(3500);}free(buf);}/*-----------------------------------------------------------------*/ over(struct process *p) /*画出结束过程*/{int i,size;void *buf;int k=evhead->pnum;setcolor(LIGHTBLUE);for(i=1;i<=28;i++)circle(440,215,i);setfillstyle(1,k);bar(476,206,476+10*p->plong,224);size=imagesize(475,205,476+10*p->plong+1,225);buf=malloc(size);getimage(475,205,476+10*p->plong+1,225,buf);for(i=0; i<=45; i++){putimage(475+i,205,buf,COPY_PUT);delay(4000);}setcolor(LIGHTBLUE);for(i=0;i<=31;i++){line(520+i,205,520+i,225);delay(4000);}free(buf);}。