进程调度模仿程序.rar_操作系统 进程调度_进程调度

#include <stdio.h> #include <stdlib.h> #include <string.h> #include <ctype.h> #define IN 1 /* 进入就绪队列 */ #define OUT 0 /* 出就绪队列 */ /*进程是程序在处理机上执行过程，进程存在的标识是进程控制块（PCB），所以应首先设计 进程控制块的结构(struct)*/ typedef struct { char name[10];/* 进程标识符 */ int prio; /* 进程优先数 */ int round; /* 进程时间轮转片 */ int cputime; /* 进程应用CPU的时间 */ int needtime;/* 进程运行需要的时间 */ int count; /* 计数器 */ char state; /* 进程的状态 */ struct node *next;/* 链指针 */ }PCB; void firstin(void); void prt1(char a); void prt2(char a,PCB *q); void prt(char algo); void insert1(PCB *q); void insert2(PCB *p2); void creat1(char alg); void creat2(char alg); void priority(char alg);/* 优先调度算法的执行函数 */ void roundrun(char alg);/* 时间片轮转算法的执行函数 */ int N; /* 进程数，设为全局变量 */ PCB *finish,*ready,*tail,*run;/* finish,ready,run分别为完成队列指针，就绪队列指针 */ /* tail为循环轮转中就绪队列的指针 */ void main() { char algo; clrscr(); printf("type the algorithm P/R(priority/roundrobin)\n"); scanf("%c",&algo); printf("Enter process number\n"); scanf("%d",&N); if(algo=='P'||algo=='p') { creat1(algo); priority(algo); } else if(algo=='R'||algo=='r') { creat2(algo); roundrun(algo); } getch(); } /*将就绪队列的第一个进程投入运行*/ void firstin() { run=ready; /* 就绪队列头指针赋值给运行头指针 */ run->state='R'; /* 进程状态变为运行态 */ ready=ready->next; /* 就绪队列头指针后移到下一个进程 */ } /*标题输出函数*/ void prt1(char a) { if(toupper(a)=='P') printf("name cputime needtime priority state\n"); else printf("name cputime needtime roundrun state\n"); } /*进程PCB的输出*/ void prt2(char a,PCB *q) { if(toupper(a)=='P') /* 优先数法输出 */ printf("%-10s%-10d%-10d%-10d%c\n",q->name,q->cputime, q->needtime,q->prio,q->state); else /* 轮转法输出 */ printf("%-10s%-10d%-10d%-10d%c\n",q->name,q->cputime, q->needtime,q->count,q->state); } void prt(char algo) { PCB *p; prt1(algo); if(run!=NULL) prt2(algo,run);/* 输出当前正在运行的PCB */ p=ready; /* 输出就绪队列的指针 */ while(p!=NULL) { prt2(algo,p); p=p->next; } p=finish; while(p!=NULL) { prt2(algo,p); p=p->next; } getch(); /* 按任意键继续 */ } /*优先插入算法*/ void insert1(PCB *q) { PCB *p1,*s,*r; int state; s=q; /*待插入PCB指针*/ p1=ready; /*就绪队列的头指针*/ r=p1; /*r为p1的前驱指针*/ state=IN; while((p1!=NULL)&&state) if(p1->prio>s->prio) { r=p1; p1=p1->next; } else state=OUT; if(r!=p1) { r->next=s; s->next=p1; } else { s->next=p1; ready=s; } } /*轮转法插入函数*/ void insert2(PCB *p2) { tail->next=p2; /*将新的PCB插入到当前就绪队列的尾*/ tail=p2; p2->next=NULL; } /*优先创建PCB的信息*/ void creat1(char alg) { PCB *p; int i,time; char na[10]; ready=finish=run=NULL; printf("Enter name and time of process\n"); for(i=1;i<=N;i++) { p=malloc(sizeof(PCB)); scanf("%s",na); scanf("%d",&time); strcpy(p->name,na); p->cputime=0; p->needtime=time; p->state='w'; p->prio=50-time; if(ready!=NULL) /*就绪队列不空，调用插入函数插入*/ insert1(p); else { p->next=ready; ready=p; } } clrscr(); printf(" Output of priority\n"); printf("***********************\n"); prt(alg); /*输出进程PCB的信息*/ run=ready; /*将就绪队列第一个进程投入使用*/ ready=ready->next; run->state='R'; } /*轮转法创建进程*/ void creat2(char alg) { PCB *p; int i,time; char na[10]; ready=finish=run=NULL; printf("Enter name and time of round process\n"); for(i=1;i<=N;i++) { p=malloc(sizeof(PCB)); scanf("%s",na); scanf("%d",&time); strcpy(p->name,na); p->cputime=0; p->needtime=time; p->count=0; p->state='w'; p->round=2; if(ready!=NULL) insert2(p); else { p->next=ready; ready=p; tail=p; } } clrscr(); printf(" output of round\n"); printf("**********************\n"); prt(alg); run=ready; ready=ready->next; run->state='R'; } /*优先数调度算法*/ void priority(char alg) { while(run!=NULL) /*当运行进程不空时，有进程正在运行*/ { run->cputime+=1; run->needtime-=1; run->prio-=3; /*每运行一次优先数降低3个单位*/ if(run->needtime==0) /*如果所需的时间为0，则将其插入完成队列*/ { run->next=finish; /*置状态为完成状态，运行头指针为空，如果就绪队列不空*/ finish=run; run->state='F'; run=NULL; if(ready!=NULL) /*将就绪队列的第一个进程投入运行*/ firstin(); } else if((ready!=NULL)&&(run->prio<ready->prio)) { run->state='w'; insert1(run); firstin(); } prt(alg); } } void roundrun(char alg) { while(run!=NULL) { run->cputime+=1; run->needtime-=1; run->count+=1; if(run->needtime==0) { run->next=finish; finish=run; run->state='F'; run=NULL; if(ready!=NULL) firstin(); } else if(run->count==run->round); { run->count=0; if(ready!=NULL) { run->state='w'; insert2(run); firstin(); } } prt(alg); } }