1 //! tty刷新内核线程
2
3 use alloc::{string::ToString, sync::Arc};
4 use kdepends::thingbuf::StaticThingBuf;
5
6 use crate::{
7 arch::CurrentIrqArch,
8 driver::tty::virtual_terminal::vc_manager,
9 exception::InterruptArch,
10 process::{
11 kthread::{KernelThreadClosure, KernelThreadMechanism},
12 ProcessControlBlock, ProcessManager,
13 },
14 sched::{schedule, SchedMode},
15 };
16
17 /// 用于缓存键盘输入的缓冲区
18 static KEYBUF: StaticThingBuf<u8, 512> = StaticThingBuf::new();
19
20 static mut TTY_REFRESH_THREAD: Option<Arc<ProcessControlBlock>> = None;
21
tty_flush_thread_init()22 pub(super) fn tty_flush_thread_init() {
23 let closure =
24 KernelThreadClosure::StaticEmptyClosure((&(tty_refresh_thread as fn() -> i32), ()));
25 let pcb = KernelThreadMechanism::create_and_run(closure, "tty_refresh".to_string())
26 .ok_or("")
27 .expect("create tty_refresh thread failed");
28 unsafe {
29 TTY_REFRESH_THREAD = Some(pcb);
30 }
31 }
32
tty_refresh_thread() -> i3233 fn tty_refresh_thread() -> i32 {
34 const TO_DEQUEUE_MAX: usize = 256;
35 loop {
36 if KEYBUF.is_empty() {
37 // 如果缓冲区为空，就休眠
38 let _guard = unsafe { CurrentIrqArch::save_and_disable_irq() };
39 ProcessManager::mark_sleep(true).expect("TTY_REFRESH_THREAD can not mark sleep");
40 schedule(SchedMode::SM_NONE);
41 }
42
43 let to_dequeue = core::cmp::min(KEYBUF.len(), TO_DEQUEUE_MAX);
44 if to_dequeue == 0 {
45 continue;
46 }
47 let mut data = [0u8; TO_DEQUEUE_MAX];
48 for item in data.iter_mut().take(to_dequeue) {
49 *item = KEYBUF.pop().unwrap();
50 }
51
52 if let Some(cur_vc) = vc_manager().current_vc() {
53 let _ = cur_vc
54 .port()
55 .receive_buf(&data[0..to_dequeue], &[], to_dequeue);
56 } else {
57 // 这里由于stdio未初始化，所以无法找到port
58 // TODO: 考虑改用双端队列，能够将丢失的输入插回
59 }
60 }
61 }
62
63 /// 发送数据到tty刷新线程
send_to_tty_refresh_thread(data: &[u8])64 pub fn send_to_tty_refresh_thread(data: &[u8]) {
65 if unsafe { TTY_REFRESH_THREAD.is_none() } {
66 return;
67 }
68
69 for item in data {
70 KEYBUF.push(*item).ok();
71 }
72 let _ = ProcessManager::wakeup(unsafe { TTY_REFRESH_THREAD.as_ref().unwrap() });
73 }
74