tty.c File Reference

#include "uv.h"
#include "internal.h"
#include "spinlock.h"
#include <stdlib.h>
#include <assert.h>
#include <unistd.h>
#include <termios.h>
#include <errno.h>
#include <sys/ioctl.h>

Go to the source code of this file.

Functions
static int	uv__tty_is_slave (const int fd)
int	uv_tty_init (uv_loop_t *loop, uv_tty_t *tty, int fd, int unused)
static void	uv__tty_make_raw (struct termios *tio)
int	uv_tty_set_mode (uv_tty_t *tty, uv_tty_mode_t mode)
int	uv_tty_get_winsize (uv_tty_t *tty, int *width, int *height)
uv_handle_type	uv_guess_handle (uv_file file)
int	uv_tty_reset_mode (void)
void	uv_tty_set_vterm_state (uv_tty_vtermstate_t state)
int	uv_tty_get_vterm_state (uv_tty_vtermstate_t *state)

Variables
static int	orig_termios_fd = -1
static struct termios	orig_termios
static uv_spinlock_t	termios_spinlock = UV_SPINLOCK_INITIALIZER

Function Documentation

uv__tty_is_slave()

static int uv__tty_is_slave ( const int  fd )

static

Definition at line 69 of file tty.c.

                                          {
  int result;
#if defined(__linux__) || defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
  int dummy;
 
  result = ioctl(fd, TIOCGPTN, &dummy) != 0;
#elif defined(__APPLE__)
  char dummy[256];
 
  result = ioctl(fd, TIOCPTYGNAME, &dummy) != 0;
#elif defined(__NetBSD__)
  /*
   * NetBSD as an extension returns with ptsname(3) and ptsname_r(3) the slave
   * device name for both descriptors, the master one and slave one.
   *
   * Implement function to compare major device number with pts devices.
   *
   * The major numbers are machine-dependent, on NetBSD/amd64 they are
   * respectively:
   *  - master tty: ptc - major 6
   *  - slave tty:  pts - major 5
   */
 
  struct stat sb;
  /* Lookup device's major for the pts driver and cache it. */
  static devmajor_t pts = NODEVMAJOR;
 
  if (pts == NODEVMAJOR) {
    pts = getdevmajor("pts", S_IFCHR);
    if (pts == NODEVMAJOR)
      abort();
  }
 
  /* Lookup stat structure behind the file descriptor. */
  if (fstat(fd, &sb) != 0)
    abort();
 
  /* Assert character device. */
  if (!S_ISCHR(sb.st_mode))
    abort();
 
  /* Assert valid major. */
  if (major(sb.st_rdev) == NODEVMAJOR)
    abort();
 
  result = (pts == major(sb.st_rdev));
#else
  /* Fallback to ptsname
   */
  result = ptsname(fd) == NULL;
#endif
  return result;
}

References fd, fstat, ioctl, major, NULL, sb, and TIOCGPTN.

Referenced by uv_tty_init().

uv__tty_make_raw()

static void uv__tty_make_raw ( struct termios *  tio )

static

Definition at line 231 of file tty.c.

                                                  {
  assert(tio != NULL);
 
#if defined __sun || defined __MVS__
  /*
   * This implementation of cfmakeraw for Solaris and derivatives is taken from
   * http://www.perkin.org.uk/posts/solaris-portability-cfmakeraw.html.
   */
  tio->c_iflag &= ~(IMAXBEL | IGNBRK | BRKINT | PARMRK | ISTRIP | INLCR |
                    IGNCR | ICRNL | IXON);
  tio->c_oflag &= ~OPOST;
  tio->c_lflag &= ~(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
  tio->c_cflag &= ~(CSIZE | PARENB);
  tio->c_cflag |= CS8;
#else
  cfmakeraw(tio);
#endif /* #ifdef __sun */
}

References assert(), BRKINT, termios::c_cflag, termios::c_iflag, termios::c_lflag, termios::c_oflag, CS8, CSIZE, ECHO, ECHONL, ICANON, ICRNL, IEXTEN, IGNBRK, IGNCR, IMAXBEL, INLCR, ISIG, ISTRIP, IXON, NULL, OPOST, PARENB, and PARMRK.

Referenced by uv_tty_set_mode().

uv_guess_handle()

uv_handle_type uv_guess_handle

(

uv_file

file

)

Definition at line 315 of file tty.c.

                                             {
  struct sockaddr sa;
  struct stat s;
  socklen_t len;
  int type;
 
  if (file < 0)
    return UV_UNKNOWN_HANDLE;
 
  if (isatty(file))
    return UV_TTY;
 
  if (fstat(file, &s))
    return UV_UNKNOWN_HANDLE;
 
  if (S_ISREG(s.st_mode))
    return UV_FILE;
 
  if (S_ISCHR(s.st_mode))
    return UV_FILE;  /* XXX UV_NAMED_PIPE? */
 
  if (S_ISFIFO(s.st_mode))
    return UV_NAMED_PIPE;
 
  if (!S_ISSOCK(s.st_mode))
    return UV_UNKNOWN_HANDLE;
 
  len = sizeof(type);
  if (getsockopt(file, SOL_SOCKET, SO_TYPE, &type, &len))
    return UV_UNKNOWN_HANDLE;
 
  len = sizeof(sa);
  if (getsockname(file, &sa, &len))
    return UV_UNKNOWN_HANDLE;
 
  if (type == SOCK_DGRAM)
    if (sa.sa_family == AF_INET || sa.sa_family == AF_INET6)
      return UV_UDP;
 
  if (type == SOCK_STREAM) {
#if defined(_AIX) || defined(__DragonFly__)
    /* on AIX/DragonFly the getsockname call returns an empty sa structure
     * for sockets of type AF_UNIX.  For all other types it will
     * return a properly filled in structure.
     */
    if (len == 0)
      return UV_NAMED_PIPE;
#endif /* defined(_AIX) || defined(__DragonFly__) */
 
    if (sa.sa_family == AF_INET || sa.sa_family == AF_INET6)
      return UV_TCP;
    if (sa.sa_family == AF_UNIX)
      return UV_NAMED_PIPE;
  }
 
  return UV_UNKNOWN_HANDLE;
}

Referenced by uv_tty_init().

uv_tty_get_vterm_state()

int uv_tty_get_vterm_state

(

uv_tty_vtermstate_t *

state

)

Definition at line 400 of file tty.c.

                                                       {
  return UV_ENOTSUP;
}

uv_tty_get_winsize()

int uv_tty_get_winsize	(	uv_tty_t *	tty,
		int *	width,
		int *	height
	)

Definition at line 297 of file tty.c.

                                                               {
  struct winsize ws;
  int err;
 
  do
    err = ioctl(uv__stream_fd(tty), TIOCGWINSZ, &ws);
  while (err == -1 && errno == EINTR);
 
  if (err == -1)
    return UV__ERR(errno);
 
  *width = ws.ws_col;
  *height = ws.ws_row;
 
  return 0;
}

uv_tty_init()

int uv_tty_init	(	uv_loop_t *	loop,
		uv_tty_t *	tty,
		int	fd,
		int	unused
	)

Definition at line 123 of file tty.c.

                                                                    {
  uv_handle_type type;
  int flags;
  int newfd;
  int r;
  int saved_flags;
  int mode;
  char path[256];
  (void)unused; /* deprecated parameter is no longer needed */
 
  /* File descriptors that refer to files cannot be monitored with epoll.
   * That restriction also applies to character devices like /dev/random
   * (but obviously not /dev/tty.)
   */
  type = uv_guess_handle(fd);
  if (type == UV_FILE || type == UV_UNKNOWN_HANDLE)
    return UV_EINVAL;
 
  flags = 0;
  newfd = -1;
 
  /* Save the fd flags in case we need to restore them due to an error. */
  do
    saved_flags = fcntl(fd, F_GETFL);
  while (saved_flags == -1 && errno == EINTR);
 
  if (saved_flags == -1)
    return UV__ERR(errno);
  mode = saved_flags & O_ACCMODE;
 
  /* Reopen the file descriptor when it refers to a tty. This lets us put the
   * tty in non-blocking mode without affecting other processes that share it
   * with us.
   *
   * Example: `node | cat` - if we put our fd 0 in non-blocking mode, it also
   * affects fd 1 of `cat` because both file descriptors refer to the same
   * struct file in the kernel. When we reopen our fd 0, it points to a
   * different struct file, hence changing its properties doesn't affect
   * other processes.
   */
  if (type == UV_TTY) {
    /* Reopening a pty in master mode won't work either because the reopened
     * pty will be in slave mode (*BSD) or reopening will allocate a new
     * master/slave pair (Linux). Therefore check if the fd points to a
     * slave device.
     */
    if (uv__tty_is_slave(fd) && ttyname_r(fd, path, sizeof(path)) == 0)
      r = uv__open_cloexec(path, mode | O_NOCTTY);
    else
      r = -1;
 
    if (r < 0) {
      /* fallback to using blocking writes */
      if (mode != O_RDONLY)
        flags |= UV_HANDLE_BLOCKING_WRITES;
      goto skip;
    }
 
    newfd = r;
 
    r = uv__dup2_cloexec(newfd, fd);
    if (r < 0 && r != UV_EINVAL) {
      /* EINVAL means newfd == fd which could conceivably happen if another
       * thread called close(fd) between our calls to isatty() and open().
       * That's a rather unlikely event but let's handle it anyway.
       */
      uv__close(newfd);
      return r;
    }
 
    fd = newfd;
  }
 
skip:
  uv__stream_init(loop, (uv_stream_t*) tty, UV_TTY);
 
  /* If anything fails beyond this point we need to remove the handle from
   * the handle queue, since it was added by uv__handle_init in uv_stream_init.
   */
 
  if (!(flags & UV_HANDLE_BLOCKING_WRITES))
    uv__nonblock(fd, 1);
 
#if defined(__APPLE__)
  r = uv__stream_try_select((uv_stream_t*) tty, &fd);
  if (r) {
    int rc = r;
    if (newfd != -1)
      uv__close(newfd);
    QUEUE_REMOVE(&tty->handle_queue);
    do
      r = fcntl(fd, F_SETFL, saved_flags);
    while (r == -1 && errno == EINTR);
    return rc;
  }
#endif
 
  if (mode != O_WRONLY)
    flags |= UV_HANDLE_READABLE;
  if (mode != O_RDONLY)
    flags |= UV_HANDLE_WRITABLE;
 
  uv__stream_open((uv_stream_t*) tty, fd, flags);
  tty->mode = UV_TTY_MODE_NORMAL;
 
  return 0;
}

uv_tty_reset_mode()

int uv_tty_reset_mode

(

void

)

Definition at line 378 of file tty.c.

                            {
  int saved_errno;
  int err;
 
  saved_errno = errno;
  if (!uv_spinlock_trylock(&termios_spinlock))
    return UV_EBUSY;  /* In uv_tty_set_mode(). */
 
  err = 0;
  if (orig_termios_fd != -1)
    if (tcsetattr(orig_termios_fd, TCSANOW, &orig_termios))
      err = UV__ERR(errno);
 
  uv_spinlock_unlock(&termios_spinlock);
  errno = saved_errno;
 
  return err;
}

uv_tty_set_mode()

int uv_tty_set_mode	(	uv_tty_t *	tty,
		uv_tty_mode_t	mode
	)

Definition at line 250 of file tty.c.

                                                       {
  struct termios tmp;
  int fd;
 
  if (tty->mode == (int) mode)
    return 0;
 
  fd = uv__stream_fd(tty);
  if (tty->mode == UV_TTY_MODE_NORMAL && mode != UV_TTY_MODE_NORMAL) {
    if (tcgetattr(fd, &tty->orig_termios))
      return UV__ERR(errno);
 
    /* This is used for uv_tty_reset_mode() */
    uv_spinlock_lock(&termios_spinlock);
    if (orig_termios_fd == -1) {
      orig_termios = tty->orig_termios;
      orig_termios_fd = fd;
    }
    uv_spinlock_unlock(&termios_spinlock);
  }
 
  tmp = tty->orig_termios;
  switch (mode) {
    case UV_TTY_MODE_NORMAL:
      break;
    case UV_TTY_MODE_RAW:
      tmp.c_iflag &= ~(BRKINT | ICRNL | INPCK | ISTRIP | IXON);
      tmp.c_oflag |= (ONLCR);
      tmp.c_cflag |= (CS8);
      tmp.c_lflag &= ~(ECHO | ICANON | IEXTEN | ISIG);
      tmp.c_cc[VMIN] = 1;
      tmp.c_cc[VTIME] = 0;
      break;
    case UV_TTY_MODE_IO:
      uv__tty_make_raw(&tmp);
      break;
  }
 
  /* Apply changes after draining */
  if (tcsetattr(fd, TCSADRAIN, &tmp))
    return UV__ERR(errno);
 
  tty->mode = mode;
  return 0;
}

uv_tty_set_vterm_state()

void uv_tty_set_vterm_state

(

uv_tty_vtermstate_t

state

)

Definition at line 397 of file tty.c.

                                                       {
}

Variable Documentation

orig_termios

struct termios orig_termios

static

Definition at line 65 of file tty.c.

Referenced by uv_tty_reset_mode(), and uv_tty_set_mode().

orig_termios_fd

int orig_termios_fd = -1

static

Definition at line 65 of file tty.c.

Referenced by uv_tty_reset_mode(), and uv_tty_set_mode().

termios_spinlock

uv_spinlock_t termios_spinlock = UV_SPINLOCK_INITIALIZER

static

Definition at line 67 of file tty.c.

Referenced by uv_tty_reset_mode(), and uv_tty_set_mode().