diff options
Diffstat (limited to 'drivers/tty/tty_core.cc')
| -rw-r--r-- | drivers/tty/tty_core.cc | 536 |
1 files changed, 0 insertions, 536 deletions
diff --git a/drivers/tty/tty_core.cc b/drivers/tty/tty_core.cc deleted file mode 100644 index 5985bd9..0000000 --- a/drivers/tty/tty_core.cc +++ /dev/null @@ -1,536 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0-or-later */ -/* Copyright (C) 2026 Richard Qin */ - -/* - * tty_core.cc — TTY subsystem core - * - * Provides the tty_struct lifecycle, file_operations dispatch, - * and ioctl routing between the line discipline and driver. - * - * Call chain: - * sys_read → tty_fops.read → tty_read → ldisc.read - * sys_write → tty_fops.write → tty_write → ldisc.write - * sys_ioctl → tty_fops.ioctl → tty_ioctl → {core / ldisc / driver} - */ - -#include <lume/tty.h> -#include <lume/tty_ioctl.h> -#include <lume/file.h> -#include <lume/fs_types.h> -#include <lume/chardev.h> -#include <lume/signal.h> -#include <lume/signal_types.h> -#include <lume/signal_nr.h> -#include <lume/task.h> -#include <lume/pgrp.h> -#include <lume/poll.h> -#include <lume/new.h> -#include <lume/errno.h> -#include <lume/klog.h> -#include <lume/slab.h> - -#ifndef ENOIOCTLCMD -#define ENOIOCTLCMD 515 -#endif - -/* ================================================================== */ -/* Global console TTY */ -/* ================================================================== */ - -tty_struct* g_console_tty = nullptr; - -/* ================================================================== */ -/* tty_struct allocation */ -/* ================================================================== */ - -tty_struct* tty_alloc(const tty_driver* driver, int index) -{ - auto* tty = new tty_struct{}; - if (!tty) return nullptr; - - tty->index = index; - tty->driver = driver; - tty->link = nullptr; - tty->pgrp = 0; - tty->session = 0; - tty->write_cnt = 0; - tty->flags = 0; - tty->open_count = 0; - tty->driver_data = nullptr; - - tty_default_termios(&tty->termios_data); - - tty->ws.ws_row = 24; - tty->ws.ws_col = 80; - tty->ws.ws_xpixel = 0; - tty->ws.ws_ypixel = 0; - - tty->lock.init("tty"); - tty->read_wait.init("tty_rd"); - tty->write_wait.init("tty_wr"); - - /* Attach default line discipline (N_TTY) */ - tty->ldisc.ops = &n_tty_ops; - tty->ldisc.data = nullptr; - - return tty; -} - -/* ================================================================== */ -/* tty_open / tty_close */ -/* ================================================================== */ - -int tty_open(tty_struct* tty) -{ - if (!tty) return -EINVAL; - - if (tty->open_count == 0) { - /* Initialize line discipline */ - if (tty->ldisc.ops && tty->ldisc.ops->open) { - int ret = tty->ldisc.ops->open(tty); - if (ret < 0) return ret; - } - - /* Initialize driver */ - if (tty->driver && tty->driver->ops && tty->driver->ops->open) { - int ret = tty->driver->ops->open(tty); - if (ret < 0) { - if (tty->ldisc.ops && tty->ldisc.ops->close) - tty->ldisc.ops->close(tty); - return ret; - } - } - } - - tty->open_count++; - return 0; -} - -void tty_close(tty_struct* tty) -{ - if (!tty) return; - - tty->open_count--; - if (tty->open_count <= 0) { - tty->open_count = 0; - - if (tty->driver && tty->driver->ops && tty->driver->ops->close) - tty->driver->ops->close(tty); - - if (tty->ldisc.ops && tty->ldisc.ops->close) - tty->ldisc.ops->close(tty); - } -} - -/* ================================================================== */ -/* Core I/O */ -/* ================================================================== */ - -int64 tty_read(tty_struct* tty, file* fp, char* buf, uint64 count) -{ - if (!tty || !tty->ldisc.ops || !tty->ldisc.ops->read) - return -EIO; - - return tty->ldisc.ops->read(tty, fp, buf, count); -} - -int64 tty_write(tty_struct* tty, file* fp, const char* buf, uint64 count) -{ - if (!tty || !tty->ldisc.ops || !tty->ldisc.ops->write) - return -EIO; - - return tty->ldisc.ops->write(tty, fp, buf, count); -} - -/* ================================================================== */ -/* tty_receive_buf — called by driver on RX */ -/* ================================================================== */ - -void tty_receive_buf(tty_struct* tty, const char* buf, int count) -{ - if (!tty || !tty->ldisc.ops || !tty->ldisc.ops->receive_buf) - return; - - tty->ldisc.ops->receive_buf(tty, buf, count); -} - -/* ================================================================== */ -/* tty_signal_pgrp — send signal to foreground process group */ -/* ================================================================== */ - -extern int send_signal(int sig, kernel_siginfo* info, TaskControlBlock* task); - -void tty_signal_pgrp(tty_struct* tty, int sig) -{ - if (!tty) return; - - int32 pgid; - { - LockGuard guard(tty->lock); - pgid = tty->pgrp; - } - if (pgid <= 0) return; - - /* Deliver to the leader of every thread group in the foreground - * process group. ldisc paths call this for SIGINT/SIGQUIT/SIGWINCH - * etc.; previously we only signalled the current task, which was - * incorrect when the fg pgrp had multiple processes. */ - kernel_siginfo info{}; - info.si_signo = sig; - info.si_code = 0; /* SI_KERNEL would be 0x80; user rarely checks */ - for_each_pgrp_member(pgid, [&](signal_struct* s) { - if (s->leader) - send_signal(sig, &info, s->leader); - }); -} - -/* ================================================================== */ -/* tty_ioctl — ioctl dispatch */ -/* ================================================================== */ - -long tty_ioctl(tty_struct* tty, file* /*fp*/, unsigned int cmd, uint64 arg) -{ - if (!tty) return -EINVAL; - - switch (cmd) { - case TCGETS: { - auto* p = reinterpret_cast<termios*>(arg); - if (!p) return -EINVAL; - *p = tty->termios_data; - return 0; - } - - case TCSETS: - case TCSETSW: - case TCSETSF: { - auto* p = reinterpret_cast<const termios*>(arg); - if (!p) return -EINVAL; - termios old = tty->termios_data; - tty->termios_data = *p; - - /* Notify line discipline of termios change */ - if (tty->ldisc.ops && tty->ldisc.ops->set_termios) - tty->ldisc.ops->set_termios(tty, &old); - - /* If TCSETSF, flush input buffer */ - if (cmd == TCSETSF) { - if (tty->ldisc.ops && tty->ldisc.ops->flush_buffer) - tty->ldisc.ops->flush_buffer(tty); - } - return 0; - } - - case TIOCGWINSZ: { - auto* p = reinterpret_cast<winsize*>(arg); - if (!p) return -EINVAL; - *p = tty->ws; - return 0; - } - - case TIOCSWINSZ: { - auto* p = reinterpret_cast<const winsize*>(arg); - if (!p) return -EINVAL; - winsize old = tty->ws; - tty->ws = *p; - if (old.ws_row != tty->ws.ws_row || old.ws_col != tty->ws.ws_col) { - tty_signal_pgrp(tty, SIGWINCH); - } - return 0; - } - - case TIOCGPGRP: { - auto* p = reinterpret_cast<int32*>(arg); - if (!p) return -EINVAL; - - TaskControlBlock* curr = current_task(); - if (!curr || !curr->signal) return -ENOTTY; - if (curr->signal->tty != tty) return -ENOTTY; - - int32 pgid; - { - LockGuard guard(tty->lock); - pgid = tty->pgrp != 0 ? tty->pgrp : curr->signal->pgid; - } - *p = pgid; - return 0; - } - - case TIOCSPGRP: { - auto* p = reinterpret_cast<const int32*>(arg); - if (!p) return -EINVAL; - - TaskControlBlock* curr = current_task(); - if (!curr || !curr->signal) return -ENOTTY; - if (curr->signal->tty != tty) return -ENOTTY; - - int32 new_pgid = *p; - if (new_pgid <= 0) return -EINVAL; - - /* new_pgid must be in the caller's session. */ - bool ok = false; - for_each_pgrp_member(new_pgid, [&](signal_struct* s) { - if (s->sid == curr->signal->sid) ok = true; - }); - if (!ok) return -EPERM; - - LockGuard guard(tty->lock); - tty->pgrp = new_pgid; - return 0; - } - - case TIOCSCTTY: { - /* Become the controlling terminal of the caller's session. - * Linux: only session leader without ctty may do this; with - * arg==1, CAP_SYS_ADMIN may steal a ctty from another session. - * We support the basic path; "steal" is left unimplemented. */ - TaskControlBlock* curr = current_task(); - if (!curr || !curr->signal) return -EPERM; - signal_struct* sig = curr->signal; - - if (sig->sid != curr->pid) return -EPERM; /* not leader */ - - LockGuard sg(sig->lock); - if (sig->tty != nullptr) return -EPERM; /* already have one */ - - LockGuard tg(tty->lock); - if (tty->session != 0 && tty->session != sig->sid) { - return -EPERM; /* owned elsewhere */ - } - tty->session = sig->sid; - tty->pgrp = sig->pgid; - sig->tty = tty; - return 0; - } - - case TIOCNOTTY: { - /* Detach from controlling terminal. */ - TaskControlBlock* curr = current_task(); - if (!curr || !curr->signal) return -ENOTTY; - signal_struct* sig = curr->signal; - if (sig->tty != tty) return -ENOTTY; - - /* Session leader: HUP everyone left in the old fg pgrp. - * Job-control conformance — without this, daemons spawned by - * a relinquishing leader keep blocking on a dead terminal. */ - bool was_leader = (sig->sid == curr->pid); - int32 hup_pgrp = 0; - { - LockGuard tg(tty->lock); - hup_pgrp = tty->pgrp; - if (was_leader) { - tty->session = 0; - tty->pgrp = 0; - } - } - { - LockGuard sg(sig->lock); - sig->tty = nullptr; - } - if (was_leader && hup_pgrp > 0) { - tty_signal_pgrp(tty, SIGHUP); - tty_signal_pgrp(tty, SIGCONT); - (void)hup_pgrp; - } - return 0; - } - - case FIONREAD: { - /* Delegate to line discipline */ - if (tty->ldisc.ops && tty->ldisc.ops->ioctl) { - int ret = tty->ldisc.ops->ioctl(tty, cmd, arg); - if (ret != -ENOIOCTLCMD) - return ret; - } - return 0; - } - - case TCFLSH: { - int queue = static_cast<int>(arg); - if (queue == 0 || queue == 2) { - /* Flush input */ - if (tty->ldisc.ops && tty->ldisc.ops->flush_buffer) - tty->ldisc.ops->flush_buffer(tty); - } - if (queue == 1 || queue == 2) { - /* Flush output */ - if (tty->driver && tty->driver->ops && tty->driver->ops->flush_buffer) - tty->driver->ops->flush_buffer(tty); - } - return 0; - } - - default: - break; - } - - /* Try line discipline ioctl */ - if (tty->ldisc.ops && tty->ldisc.ops->ioctl) { - int ret = tty->ldisc.ops->ioctl(tty, cmd, arg); - if (ret != -ENOIOCTLCMD) - return ret; - } - - /* Try driver ioctl */ - if (tty->driver && tty->driver->ops && tty->driver->ops->ioctl) { - int ret = tty->driver->ops->ioctl(tty, cmd, arg); - if (ret != -ENOIOCTLCMD) - return ret; - } - - return -ENOTTY; -} - -/* ================================================================== */ -/* file_operations for TTY devices */ -/* ================================================================== */ - -static int64 tty_fops_read(file* fp, char* buf, uint64 count, int64* /*pos*/) -{ - auto* tty = static_cast<tty_struct*>(fp->private_data); - return tty_read(tty, fp, buf, count); -} - -static int64 tty_fops_write(file* fp, const char* buf, uint64 count, int64* /*pos*/) -{ - auto* tty = static_cast<tty_struct*>(fp->private_data); - return tty_write(tty, fp, buf, count); -} - -static long tty_fops_ioctl(file* fp, unsigned int cmd, uint64 arg) -{ - auto* tty = static_cast<tty_struct*>(fp->private_data); - return tty_ioctl(tty, fp, cmd, arg); -} - -/* - * tty poll callback — Linux drivers/tty/tty_io.c:tty_poll() does the - * same thing: register tty->read_wait so the poller is woken on input, - * then ask the ldisc whether data is currently available. Write side - * is always considered ready since our writes don't block. - */ -extern bool n_tty_input_ready(tty_struct* tty); -extern void poll_wait(file*, WaitQueue*, poll_table*); - -static uint32 tty_fops_poll(file* fp, void* pt) -{ - auto* tty = static_cast<tty_struct*>(fp->private_data); - if (!tty) return POLLNVAL; - - poll_wait(fp, &tty->read_wait, static_cast<poll_table*>(pt)); - - uint32 mask = POLLOUT | POLLWRNORM; /* always writable */ - if (n_tty_input_ready(tty)) - mask |= POLLIN | POLLRDNORM; - return mask; -} - -/* - * Auto-acquire a controlling terminal on open. - * - * POSIX rule: when a session leader without a controlling tty opens a - * terminal that itself has no controlling session, and the caller did - * not pass O_NOCTTY, that terminal becomes the controlling terminal of - * the caller's session. tty->session and tty->pgrp are seeded from the - * caller's sid/pgid so that the very first tcgetpgrp() call returns a - * value matching the caller's pgid — which is precisely what BusyBox - * ash:setjobctl() needs to exit its setup loop. - * - * Reference: Linux drivers/tty/tty_jobctrl.c:tty_open_proc_set_tty() - */ -static void tty_acquire_ctty(tty_struct* tty, file* fp) -{ - TaskControlBlock* curr = current_task(); - if (!curr || !curr->signal) return; - if (fp->f_flags & O_NOCTTY) return; - - signal_struct* sig = curr->signal; - - /* Must be session leader (sid == pid). */ - if (sig->sid != curr->pid) return; - - LockGuard sig_guard(sig->lock); - if (sig->tty != nullptr) return; /* already have one */ - - LockGuard tty_guard(tty->lock); - if (tty->session != 0) return; /* tty owned by another sess */ - - tty->session = sig->sid; - tty->pgrp = sig->pgid; - sig->tty = tty; -} - -static int tty_fops_open(inode* /*ip*/, file* fp) -{ - /* The console TTY is pre-allocated; just attach it */ - if (!g_console_tty) return -ENXIO; - fp->private_data = g_console_tty; - int err = tty_open(g_console_tty); - if (err == 0) { - tty_acquire_ctty(g_console_tty, fp); - } - return err; -} - -static int tty_fops_release(inode* /*ip*/, file* fp) -{ - auto* tty = static_cast<tty_struct*>(fp->private_data); - tty_close(tty); - return 0; -} - -file_operations tty_fops; - -static void init_tty_fops() -{ - tty_fops.read = tty_fops_read; - tty_fops.write = tty_fops_write; - tty_fops.unlocked_ioctl = tty_fops_ioctl; - tty_fops.poll = tty_fops_poll; - tty_fops.open = tty_fops_open; - tty_fops.release = tty_fops_release; -} - -/* ================================================================== */ -/* TTY chardev registration */ -/* ================================================================== */ - -static cdev tty_cdev; - -void tty_init() -{ - init_tty_fops(); - - /* Allocate the console TTY */ - g_console_tty = tty_alloc(&uart_tty_driver, 0); - if (!g_console_tty) { - return; - } - - /* Open the TTY (initializes ldisc + driver) */ - tty_open(g_console_tty); - - /* Leave tty->session and tty->pgrp at 0. The first session-leader - * to open /dev/console without O_NOCTTY claims it as its controlling - * terminal via tty_acquire_ctty(), which fills both fields. Pre- - * seeding them here (as we used to with the hardcoded pid==1) would - * make every subsequent acquire path see "owned by another session" - * and bail out, leaving sh's tcgetpgrp() returning -ENOTTY and - * disabling job control. */ - - /* Initialize UART RX interrupts */ - uart_tty_init(g_console_tty); - - /* Register UART as a struct console driver. - * After this, printk/klog output goes through console_write_all() - * → uart_console_write() instead of raw early_putc(). */ - extern void uart_register_console(); - uart_register_console(); - - /* Register as /dev/console chardev — replace the old console_cdev. - * We use the same major/minor (5,1) so that existing opens - * to /dev/console will get the TTY fops. */ - tty_cdev.name = "console"; - tty_cdev.dev = MKDEV(5, 1); - tty_cdev.fops = &tty_fops; - cdev_register(&tty_cdev); -} |