void
interruptHandler(IntType which)
{
switch (which) {
case TimerInt:
DEBUG('e', "TimerInt interruput\n");
if(current!=NULL){
//printf("reinserting pid %d\n",current->pid);
l_insert(readyq,current);
}
else{
//printf("current is NULL at timer interrupt\n");
}
scheduler();
break;
case ConsoleReadInt:
DEBUG('e', "ConsoleReadInt interrupt\n");
if(consolewait !=NULL){
V_kt_sem(consolewait);
}
if(current!=NULL){
l_insert(readyq,current);
}
scheduler();
break;
case ConsoleWriteInt:
DEBUG('e', "ConsoleWriteInt interrupt\n");
if(writeok!=NULL){
//printf("increment writeok\n");
V_kt_sem(writeok);
}
/*
if(current!=NULL){
printf("reinserting pid %d\n",p->pid);
l_insert(readyq,*p);
}
*/
else{
//printf("this shouldn't happen\n");
}
scheduler();
break;
default:
DEBUG('e', "Unknown interrupt\n");
scheduler();
break;
}
}
void *readFromConsole() {
while (1) {
P_kt_sem(consoleWait);
char newChar = console_read();
if (CRBisFull() == 0) {
writeCRB(&newChar);
V_kt_sem(nelem);
}
}
//V_kt_sem(readok);
}
void console_buf(struct CharBuf *charbuf)
{
while(1) {
P_kt_sem(consoleWait);
P_kt_sem(nslots);
charbuf->buffer[charbuf->tail] = console_read();
charbuf->tail = (charbuf->tail+1) % 256;
V_kt_sem(nelem);
if (bufCount < 256)
bufCount++;
}
}
//Console buffer. Code buffers input from the console until a program requests it with a call to read(). CREATE.
//a thread whose sole job is to read characters from the console and put them into a buffer.
void *console_buffer(void *arg)
{
//printf("Goes into the console_buffer\n");
// int cbTail = 0;
//int cbHead =0;
//char *filename = (char *)arg;
//these are used to convert the char to int and place into buf
int i;
char c;
//int stop =1;
PIPE *pipe= (PIPE *)arg;
//printf("Enters console_buffer\n");
//while(stop)
while(pipe->ref_count!=0) //bc it it is then you have to deallocate
{
P_kt_sem(consoleWait);
//printf("P_kt_sem(consoleWait): %i\n",kt_getval(consoleWait));
//have to check if the buffer is full or not
//printf("Enters while loop in console\n");
//if not full yet
//if (cbTail !=cbSize)
if (pipe->pbuf_tail!=256)
{
//printf("We are reading from the console into the buffer\n");
//currently a char
c = console_read();
// printf("Reading from console: %c\n", c);
//conversion to a int bc buffer holds ints only
i = c -'0';
// printf("Coverted c into i: %i\n",i);
//enqueue - insert it into the buffer cb, enter through the back! and 256 size of the buffer
//cbTail = (cbTail+1)%256; //this is a shortcut
pipe->pbuf_tail = (pipe->pbuf_tail+1)%256;
pipe->read_buf[pipe->pbuf_tail] = i;
//printf("Placed into cb[%i]: %i\n", cbTail, cb[cbTail]);
// printf("This is in index %i: %c %i\n", cbTail, c, cb[cbTail]);
//Step 17:
V_kt_sem(nelem);
//printf("V_kt_sem(nelem): %i\n",kt_getval(nelem));
}
}
// printf("Exits while loop in console buffer\n");
kt_exit();
}
void *console_buf_read(void *arg) {
char c;
int i;
while (sysStopRead != 1) {
P_kt_sem(consoleWait);
if (!full(consoleBufferTail, consoleSize)) {
c = console_read();
i = c - '0';
add_to_queue(consoleBuffer, &consoleBufferTail, i);
V_kt_sem(nelem);
}
}
kt_exit();
}
void do_read(PCB *pcb){
int fd = pcb->registers[5],
buf = pcb->registers[6],
count = pcb->registers[7];
//printf("COUNT COUNT COUNT::::%d",count);
if(valid_fd(pcb, fd, FD_READ)){ //todo: or valid fd
if(buf < 0){
syscall_return(pcb,-1*EFAULT);
}
}else{
syscall_return(pcb,-1*EBADF); //Bad file number
}
struct File_Descriptor *fd_obj = pcb->fd_table[fd];
//if(!fd_obj->console_flag){
//printf("do_read: %d %d %d\n", fd, buf, count);
//}
if(check_buffer_address(pcb, buf) == FALSE){
syscall_return(pcb, -1*EFAULT);
}
if(count < 0){
syscall_return(pcb, -1*EINVAL);
}
int i = 0;
int val;
//printf("\ngot here to 1\n");
for(; i < count; i++){
//printf("obj id:%d, console flag:%d\n", fd_obj->id, fd_obj->console_flag);
if(fd_obj->console_flag){
//printf("\ngot here to 0000\n");
P_kt_sem(nelem);
Dllist first = dll_first(console_read_buf);
val = jval_i(dll_val(first));
dll_delete_node(first);
console_read_buf_size -= 1;
}else{
//HMM, do we need a lock for buffer access?
//printf("\ngot here to 2\n");
struct Pipe *pipe = fd_obj->pipe;
//printf("read from pipe: %p\n", pipe);
//printf("r:b\n");
P_kt_sem(pipe->empty_sem);
val = pipe->buff[pipe->buff_start];
//printf("r:(%d) %c\n",val, val);
pipe->buff_start++;
if(pipe->buff_start == PIPE_BUFF_SIZE){
pipe->buff_start = 0;
}
//printf("\ngot here to 2.5\n");
V_kt_sem(pipe->full_sem);
//printf("\ngot here to 3\n")
//printf("r:a\n");;
if(pipe->buff_start == pipe->buff_end){
break;
}
}
if(val == -1 || val == 0){
break;
}
main_memory[pcb->User_Base+buf+i] = val;
}
if(!fd_obj->console_flag){
//printf("read done\n");
}
//printf("syscall return\n");
syscall_return(pcb, i);
}
