multilevelRR

schedule.c

#include "schedule.h$"$

#include

$/**$

$*$ Function to initialize any global variables for the scheduler.

$*/$

void init$()\{$

$\}$

$/**$

$*$ Function to add a process to the scheduler

$*$ @Param process $-$ Pointer to the process control block for the process that

$*$ needs to be scheduled. PCB is defined in the header.

$*$ @return true$/$false response for if the addition was successful

$*/$

int addProcess$($PCB$*$ process$)\{$

return $0$;

$\}$

$/**$

$*$ Function to get the next process from the scheduler

$*$ @Param time $-$ pass by reference variable to store the quanta of time

$*$ the scheduled process should run for

$*$ @Return returns pointer to process control block that needs to be executed

$*$ returns NULL if there is no process to be scheduled.

$*/$

PCB$*$ nextProcess$($int $*$time$)\{$

return NULL;

$\}$

$/**$

$*$ Function that returns a boolean $1$ True$/0$ False based on if there are any

$*$ processes still scheduled

$*$ @Return $1$ if there are processes still scheduled $0$ if there are no more

$*$ scheduled processes

$*/$

int hasProcess$()\{$

return $0$;

schedule.h

#ifndef $\_$schedule$\_$h$\_$

#define $\_$schedule$\_$h$\_$

typedef struct

$\{$

int pid;

int priority;

$\}$ PCB;

void init$()$;

int addProcess$($PCB$*$ process$)$;

PCB$*$ nextProcess$($int $*$time$)$;

int hasProcess$()$;

#endif

sim.c

#include

#include

#include

#include

#include

#include

#include

#include

#include "schedule.h$"$

$//$

$//$ main $-$ The simulator's main routine

$//$

int main$($int argc, char $**$argv$)\{$

int processes$[14]$;

init$()$;

int i;

for$($i$=0$;i$<10$;i$++)\{$

processes$[$i$]=100$;

int priority $=$ i$\%4$;

printf$("$Scheduled Process: $\%$d$,$ Priority:$\%$d

$",$ i$,$ priority$)$;

PCB$*$ proc $=($PCB $*)$ malloc$($sizeof$($PCB$))$;

proc$->$pid $=$ i;

proc$->$priority$=$priority;

addProcess$($proc$)$;

$\}$

PCB$*$ process $=$ NULL;

int count $=0$;

int time $=0$;

while$($hasProcess$())\{$

process $=$ nextProcess$($&time$)$;

if$(!$process$)\{$

printf$("$NULL Process, something went wrong in your code.

$")$;

exit$(1)$;

$\}$

for$($;time$>0$;time$--)\{$

printf$("$Process $\%$d executed

$",$ process$->$pid$)$;

processes$[$process$->$pid$]--$;

if$($processes$[$process$->$pid$]<0)\{$

printf$("$Process $\%$d Finished

$",$ process$->$pid$)$;

$\}$

count$++$;

$\}$

if$($processes$[$process$->$pid$]>=0)\{$

addProcess$($process$)$;

$\}$ else $\{$

free$($process$)$;

$\}$

if$($count$==400)\{$

for$($;i$<14$;i$++)\{$

processes$[$i$]=100$;

int priority $=$ i$\%4$;

printf$("$Scheduled Process: $\%$d$,$ Priority:$\%$d

$",$ i$,$ priority$)$;

PCB$*$ proc $=($PCB $*)$ malloc$($sizeof$($PCB$))$;

proc$->$pid $=$ i;

proc$->$priority$=$priority;

addProcess$($proc$)$;

$\}$

$\}$

$\}$

exit$(0)$; $//$control never reaches here

$\}$