void suspendPCB(char PCBName[20]){
PCB *process;
int sus;//suspended
int sta;//state
process = findPCB(PCBName); //find PCB
if(process==NULL){
print("Error: PCB not found");
}
else{//if found PCB
//check sus state
sus = (process->suspended);
sta = (process->state);
if(sus==0){//if PCB is not suspended
if((sta==0)){ //if state is blocked
removePCB(process);//remove from blockedQueue
process->suspended = 1;//change state to suspended
insertPCB(process);//insert into suspendedBlockedQueue
}
else if((sta==2)){
removePCB(process);//remove from readyQueue
process->suspended = 1;//change state to suspended
insertPCB(process);//insert into suspendedReadyQueue
}
else if(sta==1){//if state is running
print("Error: PCB is running");
}
else{//if state is invalid
print("Error: PCB state is invalid");
}
}
else if(sus==1){
print("Error: Process is already suspended");
}
else{
print("Error: Suspended state invalid");
}
}
}
void loadComHandler(){
PCB *thePCB;
context *con;
thePCB = setupPCB("ComHandler",127,SYS);
thePCB->state= READY;
con=(context*)thePCB->stackTop;
con->IP = FP_OFF(&prompt);
con->CS = FP_SEG(&prompt);
con->FLAGS = 0x200;
con->DS = _DS;
con->ES = _ES;
insertPCB(thePCB);
}
void setPCBpriority(char PCBName[20], int inputPriority){
PCB *process = findPCB(PCBName); //find PCB
if((inputPriority < -128) || (inputPriority > 127)){
//if incorrect input priority
print("Error: Invalid Priority: Must be between -128 and +127\n");
}
else if(process==NULL){
print("Error: PCB not found\n");
}
else{
removePCB(process);
process -> priority = inputPriority;
insertPCB(process);
}
}
void setPriority()
{
serial_print("Please enter the name of the process to alter: ");
char* name = polling();
PCB *target = findPCB(name);
if(target == NULL)
{
serial_print("Process not found: \"");
serial_print(name);
serial_println("\" is not a valid process name");
}
else
{
serial_print("What is the new priority? ");
char* newPriority = polling();
int priority = atoi(newPriority);
if(-1 < priority && 10 > priority)
{
target->priority = priority;
int readyIndex = indexByNameReady(name);
int blockedIndex = indexByNameBlocked(name);
if (readyIndex >= 0) {
removePCBAtIndexReady(readyIndex);
} else {
removePCBAtIndexBlocked(blockedIndex);
}
insertPCB(target);
serial_print("The process \"");
serial_print(name);
serial_println("\" has successfully updated its priority");
}
else
{
serial_println("Cannot set priority: invalid range");
}
sys_free_mem(newPriority);
}
sys_free_mem(name);
sys_free_mem(target);
serial_println("");
}
void IOScheduler(){
if(param_ptr->device_id==TERMINAL||param_ptr->device_id==COM_PORT){
IOD *Descriptor = sys_alloc_mem(sizeof(IOD));
Descriptor->ppt = COP;
strcpy(Descriptor->PCBName,COP->processName);
Descriptor->buffer = param_ptr->buf_addr;
Descriptor->count = param_ptr->count_addr;
Descriptor->requestType = param_ptr->op_code;
if(param_ptr->device_id==TERMINAL){
if(TerminalQueue-> count == 0){
TerminalQueue->head = Descriptor;
TerminalQueue->tail = Descriptor;
TerminalQueue->count = 1;
ProcessIORequest(1);
}else{
TerminalQueue->tail->next = Descriptor;
TerminalQueue->tail = TerminalQueue->tail->next;
TerminalQueue->count++;
}
}else if(param_ptr->device_id==COM_PORT){
if(Com_PortQueue-> count == 0){
Com_PortQueue->head = Descriptor;
Com_PortQueue->tail = Descriptor;
Com_PortQueue->count = 1;
ProcessIORequest(2);
}else{
Com_PortQueue->tail->next = Descriptor;
Com_PortQueue->tail = Com_PortQueue->tail->next;
Com_PortQueue->count++;
}
}
COP->state = 0;
insertPCB(COP);
//blockPCB(COP->processName);
}
}