操作系统进程调度实验，把老师代码完善了一下，实现了优先级调度和时间片轮转算法，这里如果有同样在做实验的小伙伴，可以借鉴一下
 [C] 纯文本查看 复制代码 #define _CRT_SECURE_NO_WARNINGS
#pragma warning(disable:6031)
#include <stdio.h>
#include <dos.h>
#include <assert.h>
#include <stdlib.h>
#include <conio.h>
#include <io.h>
#include <windows.h>
#define P_NUM 3
#define P_TIME 50
enum state {
ready,
execute,
block,
finish
};
struct pcb {
char name[4];
int priority;
int cputime;
int needtime;
int count;
int round;
enum state process;
struct pcb* next;
};
struct pcb* get_process();
struct pcb* get_process() {
struct pcb* q = NULL;
struct pcb* t = NULL;
struct pcb* p = NULL;
int i = 0;
printf("input name and needtime,please input 3 processes\n");
while (i < P_NUM) {
q = (struct pcb*)malloc(sizeof(struct pcb));
assert(q);
scanf("%s", &(q->name));
scanf("%d", &(q->needtime));
q->cputime = 0;
q->priority = P_TIME - q->needtime;
q->process = ready;
q->next = NULL;
if (i == 0) {
p = q;
t = q;
}
else {
t->next = q;
t = q;
}
i++;
}/*while*/
return p;
}
void display(struct pcb* p) {
printf("name cputime needtime priority state\n");
while (p) {
printf("%s", p->name);
printf(" ");
printf("%d", p->cputime);
printf(" ");
printf("%d", p->needtime);
printf(" ");
printf("%d", p->priority);
printf(" ");
switch (p->process) {
case ready:
printf("ready\n");
break;
case execute:
printf("execute\n");
break;
case block:
printf("block\n");
break;
case finish:
printf("finish\n");
break;
}
p = p->next;
}
}
int process_finish(struct pcb* q) {
int bl = 1;
while (bl && q) {
bl = bl && q->needtime == 0;
q = q->next;
}
return bl;
}
void cpuexe(struct pcb* q) {
struct pcb* t = q;
int max_priority = 0;
while (q) {
if (q->process != finish) {
q->process = ready;
if (q->needtime == 0) {
q->process = finish;
}
}
if (max_priority < q->priority && q->process != finish) {
max_priority = q->priority;
t = q;
}
q = q->next;
}
assert(t);
if (t->needtime != 0) {
t->priority -= 3;
t->needtime--;
t->process = execute;
t->cputime++;
}
}
void priority_cal() {
struct pcb* p;
int cpu = 0;
p = get_process();
while (!process_finish(p)) {
cpu++;
printf("cputime:%d\n", cpu);
cpuexe(p);
display(p);
Sleep(5);
}
printf("All processes have finished,press any key to exit");
getch();
}
void display_menu() {
printf("CHOOSE THE ALGORITHM:\n");
printf("1 PRIORITY\n");
printf("2 ROUNDROBIN\n");
printf("3 EXIT\n");
}
struct pcb* get_process_round() {
struct pcb* q;
struct pcb* t;
struct pcb* p;
int i = 0;
printf("input name and time,please input 3 processes\n");
while (i < P_NUM) {
q = (struct pcb*)malloc(sizeof(struct pcb));
assert(q);
scanf("%s", &(q->name));
scanf("%d", &(q->needtime));
q->cputime = 0;
q->round = 0;
q->count = 0;
q->process = ready;
q->next = NULL;
if (i == 0) {
p = q;
t = q;
}
else {
t->next = q;
t = q;
}
i++;
} /*while*/
return p;
}
void cpu_round(struct pcb* q) {
q->cputime += 2;
q->needtime -= 2;
if (q->needtime < 0) {
q->needtime = 0;
}
q->count++;
q->round++;
q->process = execute;
}
struct pcb* get_next(struct pcb* k, struct pcb* head) {
struct pcb* t;
t = k;
do {
t = t->next;
} while (t && t->process == finish);
if (t == NULL) {
t = head;
while (t->next != k && t->process == finish) {
t = t->next;
}
}
return t;
}
void set_state(struct pcb* p) {
while (p) {
if (p->needtime == 0) {
p->process = finish;
}
if (p->process == execute) {
p->process = ready;
}
p = p->next;
}
}
void display_round(struct pcb* p) {
printf("NAME CPUTIME NEEDTIME COUNT ROUND STATE\n");
while (p) {
printf("%s", p->name);
printf(" ");
printf("%d", p->cputime);
printf(" ");
printf("%d", p->needtime);
printf(" ");
printf("%d", p->count);
printf(" ");
printf("%d", p->round);
printf(" ");
switch (p->process) {
case ready:
printf("ready\n");
break;
case execute:
printf("execute\n");
break;
case finish:
printf("finish\n");
break;
}
p = p->next;
}
}
void round_cal() {
struct pcb* p;
struct pcb* r;
int cpu = 0;
p = get_process_round();
r = p;
while (!process_finish(p)) {
cpu += 2;
cpu_round(r);
r = get_next(r, p);
printf("cpu %d\n", cpu);
display_round(p);
set_state(p);
Sleep(5);
}
printf("All processes have finished,press any key to exit");
getch();
}
/* 主程序 */
void main() {
int user_input;
display_menu();
scanf("%d", &user_input);
switch (user_input) {
case 1:priority_cal(); break;
case 2:round_cal(); break;
case 3:break;
default:
display_menu();
scanf("%d", &user_input);
break;
}
}
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发表于 2022-12-9 19:15
