1 files changed, 11 insertions, 9 deletions

diff --git a/sys_sppt.c b/sys_sppt.c
index be03d7d..80ae62d 100644
--- a/sys_sppt.c
+++ b/sys_sppt.c
@@ -24,7 +24,7 @@ void interrupt (*vect60)();  /* Storage for DOS int 60h */
 

 void sys_init()

 {

-    /* set up interrupt vector for MPX sys_calls */

+	/* set up interrupt vector for MPX sys_calls */

 

 	vect60 = getvect(0x60);

 	setvect(0x60,&sys_call);

@@ -42,13 +42,15 @@ void sys_exit()
 

 void interrupt dispatch()

 {

- /* your dispatcher code */

- if (ready_queue == NULL) {

-   sys_exit();

+ /*  MOD 4 dispatch */

+ do {

+   cop = cop -> next;

+ } while (cop != NULL && cop->suspend == SUSPENDED);

+

+ if (cop == NULL) {

+   _SP = sp_save;

  } else {

-   cop = ready_queue; // make the front of the queue the running process

-   remove_pcb(&ready_queue, cop);

-   _SP = cop->stack_ptr;

+   _SP = cop -> stack_ptr;

  }

 }

 

@@ -75,8 +77,8 @@ void interrupt sys_call()
 	cop->parm_add = parm_add;

 

 	// find out if the process wants to die... and kill it

-	if(parm_add->op_number != EXIT_CODE) {

-	  insert_pcb(&ready_queue, cop, 0);

+	if (parm_add->op_number == EXIT_CODE) {

+	  cop->suspend = SUSPENDED;

 	}

 

 	dispatch();