terminal.c

gcc-2.95.3 Linux下最常用的C编译器

      /* If we are scrolling down, delete AMOUNT lines at END.  Then insert
         AMOUNT lines at START. */
      if (amount > 0)
        {
          terminal_delete_lines (end, amount);
          terminal_insert_lines (start, amount);
        }

      /* If we are scrolling up, delete AMOUNT lines before START.  This
         actually does the upwards scroll.  Then, insert AMOUNT lines
         after the already scrolled region (i.e., END - AMOUNT). */
      if (amount < 0)
        {
          int abs_amount = -amount;
          terminal_delete_lines (start - abs_amount, abs_amount);
          terminal_insert_lines (end - abs_amount, abs_amount);
        }
    }
}

/* Re-initialize the terminal considering that the TERM/TERMCAP variable
   has changed. */
void
terminal_new_terminal (terminal_name)
     char *terminal_name;
{
  if (terminal_new_terminal_hook)
    (*terminal_new_terminal_hook) (terminal_name);
  else
    {
      terminal_initialize_terminal (terminal_name);
    }
}

/* Set the global variables SCREENWIDTH and SCREENHEIGHT. */
void
terminal_get_screen_size ()
{
  if (terminal_get_screen_size_hook)
    (*terminal_get_screen_size_hook) ();
  else
    {
      screenwidth = screenheight = 0;

#if defined (TIOCGWINSZ)
      {
        struct winsize window_size;

        if (ioctl (fileno (stdout), TIOCGWINSZ, &window_size) == 0)
          {
            screenwidth = (int) window_size.ws_col;
            screenheight = (int) window_size.ws_row;
          }
      }
#endif                          /* TIOCGWINSZ */

      /* Environment variable COLUMNS overrides setting of "co". */
      if (screenwidth <= 0)
        {
          char *sw = getenv ("COLUMNS");

          if (sw)
            screenwidth = atoi (sw);

          if (screenwidth <= 0)
            screenwidth = tgetnum ("co");
        }

      /* Environment variable LINES overrides setting of "li". */
      if (screenheight <= 0)
        {
          char *sh = getenv ("LINES");

          if (sh)
            screenheight = atoi (sh);

          if (screenheight <= 0)
            screenheight = tgetnum ("li");
        }

      /* If all else fails, default to 80x24 terminal. */
      if (screenwidth <= 0)
        screenwidth = 80;

      if (screenheight <= 0)
        screenheight = 24;
    }
}

/* Initialize the terminal which is known as TERMINAL_NAME.  If this
   terminal doesn't have cursor addressability, `terminal_is_dumb_p'
   becomes nonzero.  The variables SCREENHEIGHT and SCREENWIDTH are set
   to the dimensions that this terminal actually has.  The variable
   TERMINAL_HAS_META_P becomes nonzero if this terminal supports a Meta
   key.  Finally, the terminal screen is cleared. */
void
terminal_initialize_terminal (terminal_name)
     char *terminal_name;
{
  char *term, *buffer;

  terminal_is_dumb_p = 0;

  if (terminal_initialize_terminal_hook)
    {
      (*terminal_initialize_terminal_hook) (terminal_name);
      return;
    }

  term = terminal_name ? terminal_name : getenv ("TERM");

  if (!term_string_buffer)
    term_string_buffer = (char *)xmalloc (2048);

  if (!term_buffer)
    term_buffer = (char *)xmalloc (2048);

  buffer = term_string_buffer;

  term_clrpag = term_cr = term_clreol = (char *)NULL;

  if (!term)
    term = "dumb";

  if (tgetent (term_buffer, term) <= 0)
    {
      terminal_is_dumb_p = 1;
      screenwidth = 80;
      screenheight = 24;
      term_cr = "\r";
      term_up = term_dn = audible_bell = visible_bell = (char *)NULL;
      term_ku = term_kd = term_kl = term_kr = (char *)NULL;
      term_kP = term_kN = (char *)NULL;
      return;
    }

  BC = tgetstr ("pc", &buffer);
  PC = BC ? *BC : 0;

#if defined (TIOCGETP)
  {
    struct sgttyb sg;

    if (ioctl (fileno (stdout), TIOCGETP, &sg) != -1)
      ospeed = sg.sg_ospeed;
    else
      ospeed = B9600;
  }
#else
  ospeed = B9600;
#endif                          /* !TIOCGETP */

  term_cr = tgetstr ("cr", &buffer);
  term_clreol = tgetstr ("ce", &buffer);
  term_clrpag = tgetstr ("cl", &buffer);
  term_goto = tgetstr ("cm", &buffer);

  /* Find out about this terminals scrolling capability. */
  term_AL = tgetstr ("AL", &buffer);
  term_DL = tgetstr ("DL", &buffer);
  term_al = tgetstr ("al", &buffer);
  term_dl = tgetstr ("dl", &buffer);

  terminal_can_scroll = ((term_AL || term_al) && (term_DL || term_dl));

  term_invbeg = tgetstr ("mr", &buffer);
  if (term_invbeg)
    term_invend = tgetstr ("me", &buffer);
  else
    term_invend = (char *)NULL;

  if (!term_cr)
    term_cr =  "\r";

  terminal_get_screen_size ();

  term_up = tgetstr ("up", &buffer);
  term_dn = tgetstr ("dn", &buffer);
  visible_bell = tgetstr ("vb", &buffer);
  terminal_has_visible_bell_p = (visible_bell != (char *)NULL);
  audible_bell = tgetstr ("bl", &buffer);
  if (!audible_bell)
    audible_bell = "\007";
  term_begin_use = tgetstr ("ti", &buffer);
  term_end_use = tgetstr ("te", &buffer);

  term_keypad_on = tgetstr ("ks", &buffer);
  term_keypad_off = tgetstr ("ke", &buffer);

  /* Check to see if this terminal has a meta key. */
  terminal_has_meta_p = (tgetflag ("km") || tgetflag ("MT"));
  if (terminal_has_meta_p)
    {
      term_mm = tgetstr ("mm", &buffer);
      term_mo = tgetstr ("mo", &buffer);
    }
  else
    {
      term_mm = (char *)NULL;
      term_mo = (char *)NULL;
    }

  /* Attempt to find the arrow keys.  */
  term_ku = tgetstr ("ku", &buffer);
  term_kd = tgetstr ("kd", &buffer);
  term_kr = tgetstr ("kr", &buffer);
  term_kl = tgetstr ("kl", &buffer);

  term_kP = tgetstr ("kP", &buffer);
  term_kN = tgetstr ("kN", &buffer);

  /* If this terminal is not cursor addressable, then it is really dumb. */
  if (!term_goto)
    terminal_is_dumb_p = 1;
}

/* **************************************************************** */
/*                                                                  */
/*               How to Read Characters From the Terminal           */
/*                                                                  */
/* **************************************************************** */

#if defined (TIOCGETC)
/* A buffer containing the terminal interrupt characters upon entry
   to Info. */
struct tchars original_tchars;
#endif

#if defined (TIOCGLTC)
/* A buffer containing the local terminal mode characters upon entry
   to Info. */
struct ltchars original_ltchars;
#endif

#if defined (HAVE_TERMIOS_H)
struct termios original_termios, ttybuff;
#else
#  if defined (HAVE_TERMIO_H)
/* A buffer containing the terminal mode flags upon entry to info. */
struct termio original_termio, ttybuff;
#  else /* !HAVE_TERMIO_H */
/* Buffers containing the terminal mode flags upon entry to info. */
int original_tty_flags = 0;
int original_lmode;
struct sgttyb ttybuff;
#  endif /* !HAVE_TERMIO_H */
#endif /* !HAVE_TERMIOS_H */

/* Prepare to start using the terminal to read characters singly. */
void
terminal_prep_terminal ()
{
  int tty;

  if (terminal_prep_terminal_hook)
    {
      (*terminal_prep_terminal_hook) ();
      return;
    }

  terminal_begin_using_terminal ();

  tty = fileno (stdin);

#if defined (HAVE_TERMIOS_H)
  tcgetattr (tty, &original_termios);
  tcgetattr (tty, &ttybuff);
#else
#  if defined (HAVE_TERMIO_H)
  ioctl (tty, TCGETA, &original_termio);
  ioctl (tty, TCGETA, &ttybuff);
#  endif
#endif

#if defined (HAVE_TERMIOS_H) || defined (HAVE_TERMIO_H)
  ttybuff.c_iflag &= (~ISTRIP & ~INLCR & ~IGNCR & ~ICRNL & ~IXON);
/* These output flags are not part of POSIX, so only use them if they
   are defined.  */
#ifdef ONLCR
  ttybuff.c_oflag &= ~ONLCR ;
#endif
#ifdef OCRNL
  ttybuff.c_oflag &= ~OCRNL;
#endif
  ttybuff.c_lflag &= (~ICANON & ~ECHO);

  ttybuff.c_cc[VMIN] = 1;
  ttybuff.c_cc[VTIME] = 0;

  if (ttybuff.c_cc[VINTR] == '\177')
    ttybuff.c_cc[VINTR] = -1;

  if (ttybuff.c_cc[VQUIT] == '\177')
    ttybuff.c_cc[VQUIT] = -1;

#ifdef VLNEXT
  if (ttybuff.c_cc[VLNEXT] == '\026')
    ttybuff.c_cc[VLNEXT] = -1;
#endif /* VLNEXT */
#endif /* TERMIOS or TERMIO */

#if defined (HAVE_TERMIOS_H)
  tcsetattr (tty, TCSANOW, &ttybuff);
#else
#  if defined (HAVE_TERMIO_H)
  ioctl (tty, TCSETA, &ttybuff);
#  endif
#endif

#if !defined (HAVE_TERMIOS_H) && !defined (HAVE_TERMIO_H)
  ioctl (tty, TIOCGETP, &ttybuff);

  if (!original_tty_flags)
    original_tty_flags = ttybuff.sg_flags;

  /* Make this terminal pass 8 bits around while we are using it. */
#  if defined (PASS8)
  ttybuff.sg_flags |= PASS8;
#  endif /* PASS8 */

#  if defined (TIOCLGET) && defined (LPASS8)
  {
    int flags;
    ioctl (tty, TIOCLGET, &flags);
    original_lmode = flags;
    flags |= LPASS8;
    ioctl (tty, TIOCLSET, &flags);
  }
#  endif /* TIOCLGET && LPASS8 */

#  if defined (TIOCGETC)
  {
    struct tchars temp;

    ioctl (tty, TIOCGETC, &original_tchars);
    temp = original_tchars;

    /* C-s and C-q. */
    temp.t_startc = temp.t_stopc = -1;

    /* Often set to C-d. */
    temp.t_eofc = -1;

    /* If the a quit or interrupt character conflicts with one of our
       commands, then make it go away. */
    if (temp.t_intrc == '\177')
      temp.t_intrc = -1;

    if (temp.t_quitc == '\177')
      temp.t_quitc = -1;

    ioctl (tty, TIOCSETC, &temp);
  }
#  endif /* TIOCGETC */

#  if defined (TIOCGLTC)
  {
    struct ltchars temp;

    ioctl (tty, TIOCGLTC, &original_ltchars);
    temp = original_ltchars;

    /* Make the interrupt keys go away.  Just enough to make people happy. */
    temp.t_lnextc = -1;         /* C-v. */
    temp.t_dsuspc = -1;         /* C-y. */
    temp.t_flushc = -1;         /* C-o. */
    ioctl (tty, TIOCSLTC, &temp);
  }
#  endif /* TIOCGLTC */

  ttybuff.sg_flags &= ~ECHO;
  ttybuff.sg_flags |= CBREAK;
  ioctl (tty, TIOCSETN, &ttybuff);
#endif /* !HAVE_TERMIOS_H && !HAVE_TERMIO_H */
}

/* Restore the tty settings back to what they were before we started using
   this terminal. */
void
terminal_unprep_terminal ()
{
  int tty;

  if (terminal_unprep_terminal_hook)
    {
      (*terminal_unprep_terminal_hook) ();
      return;
    }

  tty = fileno (stdin);

#if defined (HAVE_TERMIOS_H)
  tcsetattr (tty, TCSANOW, &original_termios);
#else
#  if defined (HAVE_TERMIO_H)
  ioctl (tty, TCSETA, &original_termio);
#  else /* !HAVE_TERMIO_H */
  ioctl (tty, TIOCGETP, &ttybuff);
  ttybuff.sg_flags = original_tty_flags;
  ioctl (tty, TIOCSETN, &ttybuff);

#  if defined (TIOCGETC)
  ioctl (tty, TIOCSETC, &original_tchars);
#  endif /* TIOCGETC */

#  if defined (TIOCGLTC)
  ioctl (tty, TIOCSLTC, &original_ltchars);
#  endif /* TIOCGLTC */

#  if defined (TIOCLGET) && defined (LPASS8)
  ioctl (tty, TIOCLSET, &original_lmode);
#  endif /* TIOCLGET && LPASS8 */

#  endif /* !HAVE_TERMIO_H */
#endif /* !HAVE_TERMIOS_H */
  terminal_end_using_terminal ();
}