diff options
Diffstat (limited to 'drivers/char/pty.c')
| -rw-r--r-- | drivers/char/pty.c | 57 |
1 files changed, 53 insertions, 4 deletions
diff --git a/drivers/char/pty.c b/drivers/char/pty.c index 6d4582712b1..112a6ba9a96 100644 --- a/drivers/char/pty.c +++ b/drivers/char/pty.c @@ -5,8 +5,6 @@ * * Added support for a Unix98-style ptmx device. * -- C. Scott Ananian <cananian@alumni.princeton.edu>, 14-Jan-1998 - * Added TTY_DO_WRITE_WAKEUP to enable n_tty to send POLL_OUT to - * waiting writers -- Sapan Bhatia <sapan@corewars.org> * * When reading this code see also fs/devpts. In particular note that the * driver_data field is used by the devpts side as a binding to the devpts @@ -217,7 +215,6 @@ static int pty_open(struct tty_struct *tty, struct file *filp) clear_bit(TTY_OTHER_CLOSED, &tty->link->flags); set_bit(TTY_THROTTLED, &tty->flags); - set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); retval = 0; out: return retval; @@ -230,6 +227,55 @@ static void pty_set_termios(struct tty_struct *tty, tty->termios->c_cflag |= (CS8 | CREAD); } +/** + * pty_do_resize - resize event + * @tty: tty being resized + * @real_tty: real tty (not the same as tty if using a pty/tty pair) + * @rows: rows (character) + * @cols: cols (character) + * + * Update the termios variables and send the neccessary signals to + * peform a terminal resize correctly + */ + +int pty_resize(struct tty_struct *tty, struct winsize *ws) +{ + struct pid *pgrp, *rpgrp; + unsigned long flags; + struct tty_struct *pty = tty->link; + + /* For a PTY we need to lock the tty side */ + mutex_lock(&tty->termios_mutex); + if (!memcmp(ws, &tty->winsize, sizeof(*ws))) + goto done; + + /* Get the PID values and reference them so we can + avoid holding the tty ctrl lock while sending signals. + We need to lock these individually however. */ + + spin_lock_irqsave(&tty->ctrl_lock, flags); + pgrp = get_pid(tty->pgrp); + spin_unlock_irqrestore(&tty->ctrl_lock, flags); + + spin_lock_irqsave(&pty->ctrl_lock, flags); + rpgrp = get_pid(pty->pgrp); + spin_unlock_irqrestore(&pty->ctrl_lock, flags); + + if (pgrp) + kill_pgrp(pgrp, SIGWINCH, 1); + if (rpgrp != pgrp && rpgrp) + kill_pgrp(rpgrp, SIGWINCH, 1); + + put_pid(pgrp); + put_pid(rpgrp); + + tty->winsize = *ws; + pty->winsize = *ws; /* Never used so will go away soon */ +done: + mutex_unlock(&tty->termios_mutex); + return 0; +} + static int pty_install(struct tty_driver *driver, struct tty_struct *tty) { struct tty_struct *o_tty; @@ -290,6 +336,7 @@ static const struct tty_operations pty_ops = { .chars_in_buffer = pty_chars_in_buffer, .unthrottle = pty_unthrottle, .set_termios = pty_set_termios, + .resize = pty_resize }; /* Traditional BSD devices */ @@ -319,6 +366,7 @@ static const struct tty_operations pty_ops_bsd = { .unthrottle = pty_unthrottle, .set_termios = pty_set_termios, .ioctl = pty_bsd_ioctl, + .resize = pty_resize }; static void __init legacy_pty_init(void) @@ -561,7 +609,8 @@ static const struct tty_operations ptm_unix98_ops = { .unthrottle = pty_unthrottle, .set_termios = pty_set_termios, .ioctl = pty_unix98_ioctl, - .shutdown = pty_unix98_shutdown + .shutdown = pty_unix98_shutdown, + .resize = pty_resize }; static const struct tty_operations pty_unix98_ops = { |