// ***KEYBOARD I-PROCESS***
void kbd_iproc(int sigval) {
// temporary env pointer
msg_env *temp_k = NULL;
// only continue if the flag is 1, ie there's stuff in the buffer
if (*in_mem_p->ok_flag == 1) {
// start at the beginning of the buffer
buf_index = 0;
// get a pointer to the kb-iprocess PCB
PCB * temp = convert_PID(0);
//dequeue env from Keyboard env queue into temp
temp_k = env_DEQ(temp->receive_msg_Q);
// if the dequeued env is not NULL
if (temp_k == NULL)
return;
// read buffer into the env, while we haven't reached the NULL
do {
temp_k->msg_text[buf_index] = in_mem_p->indata[buf_index];
buf_index++;
} while (in_mem_p->indata[buf_index - 1] != '\0');
// printf("Keyboard input was: %s\n",in_mem_p->indata); //used for debugging
// reset flag
*in_mem_p->ok_flag = 0;
// set the env message type to 'console input'
strcpy(temp_k->msg_type, "console_input");
// send env back to process
int Z = send_message(4, temp_k);
// if it didn't send like it should have
if (Z == 0)
printf("Error with sending\n");
}
/* if the buffer was empty (ie flag != 1)
else
printf("There is no input in the memory to read in!\n"); */
}
void crt_iproc(int sigval) {
// temporary env pointer
msg_env *temp_c = NULL;
// put stuff in buffer only if the buffer is empty
if (*out_mem_p->oc_flag == 0) {
buf_index = 0;
// dequeue env into msg_env
temp_c = env_DEQ(convert_PID(1)->receive_msg_Q);
// if the envelope is NULL don't continue
if (temp_c == NULL)
return;
// read env into the buffer
do {
out_mem_p->outdata[buf_index] = temp_c->msg_text[buf_index];
buf_index++;
} while (out_mem_p->outdata[buf_index - 1] != '\0');
// set flag so UART will read memory
*out_mem_p->oc_flag = 1;
// set env message type to 'display ack'
strcpy(temp_c->msg_type, "display_ack");
// send env back to process
int Z = send_message(4, temp_c); //fix this later, sender_id is 31
// if sending is stupid
if (Z == 0)
printf("Error with sending\n");
}
/* if memory is full (ie. flag != 0)
else{
printf("fix the function!!!!\n"); */
}
// ***RECEIVE MESSAGE***
msg_env *receive_message() { //Doesn't take the PCB as a parameter. Dealt with using curr_process
// if the receive message queue is empty
if (curr_process->receive_msg_Q->head == NULL) {
// if the process is an iprocess or should never be blocked, return a NULL pointer (ie. no env)
if (curr_process->priority == -1 || curr_process->state == "NEVER_BLK_PROC")
return NULL;
// if it's a normal process, block it on receive
strcpy(curr_process->state, "BLK_ON_RCV"); //*********Doesn't need to be put in a queue, and don't care about process switch now********* FIX THIS
return NULL; // *****TO BE FIXED WITH CONTEXT SWITCHING
}
// if the message queue is not empty, dequeue the first message in the queue
else
return env_DEQ(curr_process->receive_msg_Q);
}
// *** PROCESS A *** PID 3
void ProcessA(){
// initialize return int, count
int num = 0;
PCB* pA_pcb = convert_PID(3);
// receive the message from the CCI
msg_env* envA = receive_message();
int R = 0;
R = get_console_chars(envA);
if (R==0)
release_processor();
// deallocate the message from Proc A's queue in its PCB
envA= env_DEQ(pA_pcb->receive_msg_Q);
while(1)
{
printf("A\n");
// request an envelope
msg_env* tempEnv = request_msg_env();
if(tempEnv)
{
// set the env type and text
tempEnv->msg_type = 2;
tempEnv->msg_text[0] = num;
// send to ProcessB
int result = send_message(4, tempEnv);
num++;
}
release_processor();
}
}
// *** PROCESS C *** PID 5
void ProcessC(){
// init the local queue
struct envQ* localQ = (struct envQ *) malloc (sizeof (struct envQ));
if (localQ==NULL)
{
printf("localQ in Proc C not created properly");
return;
} // can we use the queue on the proc pcb instead?
PCB* pC_pcb = convert_PID(5);
msg_env* envC = request_msg_env();
// infinite loop of normal activity
while (1)
{
printf("A\n");
int NUM =envC->msg_text[0];
// if theres nothing the localQ, receive a message and enqueue it
if (localQ->head == NULL)
{
envC = receive_message();
int H = env_ENQ(envC,localQ);
if (H ==0)
printf("Cannot enqueue on localQ");
}
// if there is something on the localQ, dequeue it
else {
envC = env_DEQ(localQ);
}
// if the message type is count report, and the value in msg_text is evenly divisible by 20, display "Process C"
if (envC->msg_type == 2 && NUM % 20 == 0){
// send the display message
strcpy(envC->msg_text, "Process C\n\0");
int W = send_console_chars(envC); // Returns confirmation of sending
if (W==1)
{
// if it is the ack message request a delay of 10s, with wakeup code "wakeup10"
int R = request_delay(10000, WAKEUP, envC); // request_delay returns an int
if (R==0)
printf("Error with request_delay");
// wait for wakeup message
envC = receive_message();
// if its not the wakeup message put it on the local Q
while (envC->msg_type != WAKEUP)
{
envC = receive_message();
int XX = env_ENQ(envC,localQ);
if (XX==0)
printf("Error with putting message on local Q in Proc C");
}
}
else
printf("Error sending 'Process C' to screen in Proc C");
}
// deallocate envelopes
int dun = release_msg_env(envC);
if (dun==0)
printf("ERROR IN DEALLOCATING ENVELOPE AT END OF Proc C");
// release processor
release_processor();
}// end of infinite loop
}