操作系統(tǒng)實驗報告3

《操作系統(tǒng)》實驗報告實驗序號：3實驗項目名稱：作業(yè)調(diào)度的實現(xiàn)學(xué)號1209030109姓名陶爽專業(yè)、班信管1201實驗地點文波331指導(dǎo)教師屈振新時間2013.12.24一、實驗?zāi)康募耙笤趌inux環(huán)境下，完成驗證性實驗——作業(yè)調(diào)度的實現(xiàn)。二、實驗設(shè)備（環(huán)境）及要求（1）操作系統(tǒng)：Linux（2）開發(fā)環(huán)境：Linux終端（3）1G以上的CPU處理器，512MB以上的內(nèi)存，10G的自由硬盤空間三、實驗內(nèi)容與步驟程序算法如下：job.c#include<stdio.h>

#include<unistd.h>

#include<sys/types.h>

#include<sys/stat.h>

#include<sys/time.h>

#include<sys/wait.h>

#include<string.h>

#include<signal.h>

#include<fcntl.h>

#include<time.h>

#include"job.h"

intjobid=0;

intsiginfo=1;

intfifo;

intglobalfd;

structwaitqueue*head=NULL;

structwaitqueue*next=NULL,*current=NULL;

voidschedule()

{

structjobinfo*newjob=NULL;

structjobcmdcmd;

intcount=0;

bzero(&cmd,DATALEN);

if((count=read(fifo,&cmd,DATALEN))<0)

error_sys("readfifofailed");

#ifdefDEBUG

if(count){

printf("cmdcmdtype\t%d\n"

"cmddefpri\t%d\n"

"cmddata\t%s\n",

cmd.type,cmd.defpri,cmd.data);

}else

printf("nodataread\n");

#endif

switch(cmd.type){

caseENQ:

do_enq(newjob,cmd);

break;

caseDEQ:

do_deq(cmd);

break;

caseSTAT:

do_stat(cmd);

break;

default:

break;

}

/*Updatejobsinwaitqueue*/

updateall();

/*selectthehighestpriorityjobtorun*/

next=jobselect();

/*stopcurrentjob,runnextjob*/

jobswitch();

}

intallocjid()

{

return++jobid;

}

voidupdateall()

{

structwaitqueue*p;

/*updaterunningjob'srun_time*/

if(current)

current->job->run_time+=1;/*add1represent100ms*/

/*updatereadyjob'swait_time*/

for(p=head;p!=NULL;p=p->next){

p->job->wait_time+=100;

if(p->job->wait_time>=1000&&p->job->curpri<3)

p->job->curpri++;

}

}

structwaitqueue*jobselect()

{

structwaitqueue*p,*prev,*select,*selectprev;

inthighest=-1;

select=NULL;

selectprev=NULL;

if(head){

for(prev=head,p=head;p!=NULL;prev=p,p=p->next)

if(p->job->curpri>highest){

select=p;

selectprev=prev;

highest=p->job->curpri;

}

selectprev->next=select->next;

if(select==selectprev)

head=NULL;

}

returnselect;

}

voidjobswitch()

{

structwaitqueue*p;

inti;

if(current&¤t->job->state==DONE){/*currentjobfinished*/

/*jobhasbeendone,removeit*/

for(i=0;(current->job->cmdarg)[i]!=NULL;i++){

free((current->job->cmdarg)[i]);

(current->job->cmdarg)[i]=NULL;

}

free(current->job->cmdarg);

free(current->job);

free(current);

current=NULL;

}

if(next==NULL&¤t==NULL)/*nojobtorun*/

return;

elseif(next!=NULL&¤t==NULL){/*startnewjob*/

//printf("beginstartnewjob\n");

current=next;

next=NULL;

current->job->state=RUNNING;

kill(current->job->pid,SIGCONT);

return;

}elseif(next!=NULL&¤t!=NULL){/*doswitch*/

//printf("beginswitch\n");

kill(current->job->pid,SIGSTOP);

current->job->curpri=current->job->defpri;

current->job->wait_time=0;

current->job->state=READY;

/*movebacktothequeue*/

if(head){

for(p=head;p->next!=NULL;p=p->next);

p->next=current;

}else{

head=current;

}

current=next;

next=NULL;

current->job->state=RUNNING;

kill(current->job->pid,SIGCONT);

return;

}else{/*next==NULL&¤t!=NULL,noswitch*/

return;

}

}

voidsig_handler(intsig,siginfo_t*info,void*notused)

{

intstatus;

intret;

switch(sig){

caseSIGVTALRM:

schedule();

return;

caseSIGCHLD:

ret=waitpid(-1,&status,WNOHANG);

if(ret==0)

return;

if(WIFEXITED(status)){

current->job->state=DONE;

printf("normaltermation,exitstatus=%d\n",WEXITSTATUS(status));

}/*elseif(WIFSIGNALED(status)){*/

/*printf("abnormaltermation,signalnumber=%d\n",WTERMSIG(status));*/

/*}elseif(WIFSTOPPED(status)){*/

/*printf("childstopped,signalnumber=%d\n",WSTOPSIG(status));*/

/*}*/

return;

default:

return;

}

}

voiddo_enq(structjobinfo*newjob,structjobcmdenqcmd)

{

structwaitqueue*newnode,*p;

inti=0,pid;

char*offset,*argvec,*q;

char**arglist;

sigset_tzeromask;

sigemptyset(&zeromask);

/*filljobinfostruct*/

newjob=(structjobinfo*)malloc(sizeof(structjobinfo));

newjob->jid=allocjid();

newjob->defpri=enqcmd.defpri;

newjob->curpri=enqcmd.defpri;

newjob->ownerid=enqcmd.owner;

newjob->state=READY;

newjob->wait_time=0;

newjob->run_time=0;

arglist=(char**)malloc(sizeof(char*)*(enqcmd.argnum+1));

newjob->cmdarg=arglist;

offset=enqcmd.data;

argvec=enqcmd.data;

while(i<enqcmd.argnum){

if(*offset==':'){

*offset++='\0';

q=(char*)malloc(offset-argvec);

strcpy(q,argvec);

arglist[i++]=q;

argvec=offset;

}else

offset++;

}

arglist[i]=NULL;

newjob->create_time=time(NULL);

#ifdefDEBUG

printf("enqcmdargnum%d\n",enqcmd.argnum);

for(i=0;i<enqcmd.argnum;i++)

printf("parseenqcmd:%s\n",arglist[i]);

#endif

/*addnewjobtothequeue*/

newnode=(structwaitqueue*)malloc(sizeof(structwaitqueue));

newnode->next=NULL;

newnode->job=newjob;

if(head){

for(p=head;p->next!=NULL;p=p->next);

p->next=newnode;

}else

head=newnode;

/*createprocessforthejob*/

if((pid=fork())<0)

error_sys("enqforkfailed");

/*Inchildprocess*/

if(pid==0){

newjob->pid=getpid();

/*blockthechildwaitforrun*/

raise(SIGSTOP);

#ifdefDEBUG

printf("beginrunning\n");

for(i=0;arglist[i]!=NULL;i++)

printf("arglist%s\n",arglist[i]);

#endif

/*duptheglobalfiledescriptortostdout*/

//dup2(globalfd,1);

if(execv(arglist[0],arglist)<0)

printf("execfailed\n");

exit(1);

}else{

newjob->pid=pid;

}

}

/*bugtofix*/

voiddo_deq(structjobcmddeqcmd)

{

intdeqid,i;

structwaitqueue*p,*prev,*select,*selectprev;

deqid=atoi(deqcmd.data);

#ifdefDEBUG

printf("deqjid%d\n",deqid);

#endif

/*currentjodid==deqid,terminatecurrentjob*/

if(current&¤t->job->jid==deqid){

printf("terminatecurrentjob\n");

kill(SIGTERM,current->job->pid);

for(i=0;(current->job->cmdarg)[i]!=NULL;i++){

free((current->job->cmdarg)[i]);

(current->job->cmdarg)[i]=NULL;

}

free(current->job->cmdarg);

free(current->job);

free(current);

current=NULL;

}else{/*maybeinwaitqueue,searchit*/

select=NULL;

selectprev=NULL;

if(head){

for(prev=head,p=head;p!=NULL;prev=p,p=p->next)

if(p->job->jid==deqid){

select=p;

selectprev=prev;

break;

}

selectprev->next=select->next;

if(select==selectprev)

head=NULL;

}

if(select){

for(i=0;(select->job->cmdarg)[i]!=NULL;i++){

free((select->job->cmdarg)[i]);

(select->job->cmdarg)[i]=NULL;

}

free(select->job->cmdarg);

free(select->job);

free(select);

select=NULL;

}

}

}

voiddo_stat(structjobcmdstatcmd)

{

structwaitqueue*p;

intstatfd;

/*

*Printjobstatisticsofalljobs:

*1.jobid

*2.jobpid

*3.jobowner

*4.jobruntime

*5.jobwaittime

*6.jobcreatetime

*7.jobstate

*/

if((statfd=open("/tmp/stat",O_WRONLY))<0)

error_sys("openfifofailed");

if(current){

write(statfd,current->job,sizeof(structjobinfo));

}

for(p=head;p!=NULL;p=p->next){

write(statfd,p->job,sizeof(structjobinfo));

}

close(statfd);

}

intmain()

{

structtimevalinterval;

structitimervalnew,old;

structstatstatbuf;

structsigactionnewact,oldact1,oldact2;

if(stat("/tmp/server",&statbuf)==0){

/*iffifofileexists,removeit*/

if(remove("/tmp/server")<0)

error_sys("removefailed");

}

if(mkfifo("/tmp/server",0666)<0)

error_sys("mkfifofailed");

/*openfifoinnonblockmode*/

if((fifo=open("/tmp/server",O_RDONLY|O_NONBLOCK))<0)

error_sys("openfifofailed");

/*openglobalfileforjoboutput*/

if((globalfd=open("/dev/null",O_WRONLY))<0)

error_sys("openglobalfilefailed");

/*setupsigna