void TrapTtyTransmit(UserContext *user_context) {
TracePrintf(TRACE_LEVEL_FUNCTION_INFO, ">>> TrapTtyTransmit(%p)\n", user_context);
int tty_id = user_context->code;
Tty term = ttys[tty_id];
assert(!ListEmpty(term.waiting_to_transmit));
// Get the currently transmitting proc (always at the front of the list)
PCB *waiting_proc = (PCB *) ListPeak(term.waiting_to_transmit);
if (waiting_proc->tty_transmit_len > TERMINAL_MAX_LINE) {
// not completely transmitted, so handle pointer stuff and leave in
// front of the queue
waiting_proc->tty_transmit_pointer += TERMINAL_MAX_LINE;
waiting_proc->tty_transmit_len -= TERMINAL_MAX_LINE;
// transmit min(MAX_LINE, len)
if (TERMINAL_MAX_LINE > waiting_proc->tty_transmit_len) {
TtyTransmit(tty_id, waiting_proc->tty_transmit_pointer,
waiting_proc->tty_transmit_len);
} else {
TtyTransmit(tty_id, waiting_proc->tty_transmit_pointer,
TERMINAL_MAX_LINE);
}
return;
}
// transmission complete
// since done, take off transmitting list
ListRemoveById(term.waiting_to_transmit, waiting_proc->pid);
ListAppend(ready_queue, waiting_proc, waiting_proc->pid);
free(waiting_proc->tty_transmit_buffer);
if (ListEmpty(term.waiting_to_transmit)) {
return; // no other procs waiting on this term
}
// Get the next proc waiting to submit
PCB *next_to_transmit = (PCB *) ListPeak(term.waiting_to_transmit);
// transmit min(MAX_LINE, len)
if (TERMINAL_MAX_LINE > next_to_transmit->tty_transmit_len) {
TtyTransmit(tty_id, next_to_transmit->tty_transmit_pointer,
next_to_transmit->tty_transmit_len);
} else {
TtyTransmit(tty_id, next_to_transmit->tty_transmit_pointer,
TERMINAL_MAX_LINE);
}
TracePrintf(TRACE_LEVEL_FUNCTION_INFO, "<<< TrapTtyTransmit(%p)\n", user_context);
}
int Y_TtyWrite(int tty_id, void *buf, int len, UserContext *user_context)
{
int commit_len;
char *commit_buf;
int result = 0;
dnode_t *node = NULL;
//log_info("tty_id = %d, buf = %p, len = %d, pid = %d", tty_id, buf, len, running_proc->pid);
commit_buf = (void *)calloc(1, TERMINAL_MAX_LINE);
if (commit_buf == NULL) {
log_err("allocate buffer for tty transferring failed!\n");
log_info("result = %d, pid = %d", result, running_proc->pid);
return _FAILURE;
}
//log_info("calloc commit_buf done");
len = min(len, strlen(buf));
while (len) {
commit_len = min(len, TERMINAL_MAX_LINE);
memcpy(commit_buf, buf + result, commit_len);
//log_info("memcpy from buff done");
len -= commit_len;
//log_info("TTY Enqueue PID(%d) DONE", running_proc->pid);
while (is_write_busy(tty_id)) {
tty_write_enqueue(running_proc, tty_id);
pcb_t *print_proc = peek_tty_write_queue(tty_id);
//log_info("PID(%d) is waiting for printing PID(%d)", running_proc->pid, tty_writing_procs[tty_id]->pid);
next_schedule(user_context);
}
set_write_proc(running_proc, tty_id);
//log_info("PID(%d) Right before tty transmit", running_proc->pid);
TtyTransmit(tty_id, commit_buf, commit_len);
//log_info("Right after tty transmit");
next_schedule(user_context);
//log_info("Back from tty block");
result += commit_len;
}
free(commit_buf);
log_info("Len of printed chars = %d, pid = %d", result, running_proc->pid);
return result;
}
