term.c

早期freebsd实现

string_cost (str)
     char *str;
{
  cost = 0;
  if (str)
    tputs (str, 0, evalcost);
  return cost;
}

/* Compute cost of sending "str", in characters,
   counting any line-dependent padding at one line.  */
string_cost_one_line (str)
     char *str;
{
  cost = 0;
  if (str)
    tputs (str, 1, evalcost);
  return cost;
}

/* Compute per line amount of line-dependent padding,
   in tenths of characters.  */
per_line_cost (str)
     register char *str;
{
  cost = 0;
  if (str)
    tputs (str, 0, evalcost);
  cost = - cost;
  if (str)
    tputs (str, 10, evalcost);
  return cost;
}

/* ARGSUSED */
calculate_ins_del_char_costs ()
{
  int ins_startup_cost, del_startup_cost;
  int ins_cost_per_char, del_cost_per_char;
  register int i;
  register int *p;

  if (TS_ins_multi_chars)
    {
      ins_cost_per_char = 0;
      ins_startup_cost = string_cost_one_line (TS_ins_multi_chars);
    }
  else if (TS_ins_char || TS_pad_inserted_char
	   || (TS_insert_mode && TS_end_insert_mode))
    {
      ins_startup_cost = (30 * (string_cost (TS_insert_mode) + string_cost (TS_end_insert_mode))) / 100;
      ins_cost_per_char = (string_cost_one_line (TS_ins_char)
			   + string_cost_one_line (TS_pad_inserted_char));
    }
  else
    {
      ins_startup_cost = 9999;
      ins_cost_per_char = 0;
    }

  if (TS_del_multi_chars)
    {
      del_cost_per_char = 0;
      del_startup_cost = string_cost_one_line (TS_del_multi_chars);
    }
  else if (TS_del_char)
    {
      del_startup_cost = (string_cost (TS_delete_mode)
			  + string_cost (TS_end_delete_mode));
      if (delete_in_insert_mode)
	del_startup_cost /= 2;
      del_cost_per_char = string_cost_one_line (TS_del_char);
    }
  else
    {
      del_startup_cost = 9999;
      del_cost_per_char = 0;
    }

  /* Delete costs are at negative offsets */
  p = &DCICcost[0];
  for (i = screen_width; --i >= 0;)
    *--p = (del_startup_cost += del_cost_per_char);

  /* Doing nothing is free */
  p = &DCICcost[0];
  *p++ = 0;

  /* Insert costs are at positive offsets */
  for (i = screen_width; --i >= 0;)
    *p++ = (ins_startup_cost += ins_cost_per_char);
}

calculate_costs ()
{
  register char *s
    = TS_set_scroll_region ? TS_set_scroll_region : TS_set_scroll_region_1;

  if (chars_wasted != 0)
    chars_wasted = (char *) xrealloc (chars_wasted, screen_height);
  else
    chars_wasted = (char *) xmalloc (screen_height);
  bzero (chars_wasted, screen_height);

  if (copybuf != 0)
    copybuf = (char *) xrealloc (copybuf, screen_height);
  else
    copybuf = (char *) xmalloc (screen_height);

  if (DC_ICcost != 0)
    DC_ICcost = (int *) xrealloc (DC_ICcost,
				  (2 * screen_width + 1) * sizeof (int));
  else
    DC_ICcost = (int *) xmalloc ((2 * screen_width + 1) * sizeof (int));

  /* Always call CalcIDCosts because it allocates some vectors.
     That function handles dont_calculate_costs.  */
  if (s && (!TS_ins_line && !TS_del_line))
    CalcIDCosts (TS_rev_scroll, TS_ins_multi_lines,
		 TS_fwd_scroll, TS_del_multi_lines,
		 s, s);
  else
    CalcIDCosts (TS_ins_line, TS_ins_multi_lines,
		 TS_del_line, TS_del_multi_lines,
		 0, 0);

  if (dont_calculate_costs)
    {
      bzero (DC_ICcost, 2 * screen_width * sizeof (int));
      return;
    }

  calculate_ins_del_char_costs ();

  /* Don't use TS_repeat if its padding is worse than sending the chars */
  if (TS_repeat && per_line_cost (TS_repeat) * baud_rate < 9000)
    RPov = string_cost (TS_repeat);
  else
    RPov = screen_width * 2;

  cmcostinit ();		/* set up cursor motion costs */
}

term_init (terminal_type)
     char *terminal_type;
{
  char *area;
  char **address = &area;
  char buffer[2044];
  register char *p;
  int status;

  extern char *tgetstr ();

  Wcm_clear ();
  dont_calculate_costs = 0;

  status = tgetent (buffer, terminal_type);
  if (status < 0)
    fatal ("Cannot open termcap database file.\n");
  if (status == 0)
    fatal ("Terminal type %s is not defined.\n", terminal_type);

#ifdef TERMINFO
  area = (char *) malloc (2044);
#else
  area = (char *) malloc (strlen (buffer));
#endif /* not TERMINFO */
  if (area == 0)
    abort ();

  TS_ins_line = tgetstr ("al", address);
  TS_ins_multi_lines = tgetstr ("AL", address);
  TS_bell = tgetstr ("bl", address);
  TS_clr_to_bottom = tgetstr ("cd", address);
  TS_clr_line = tgetstr ("ce", address);
  TS_clr_screen = tgetstr ("cl", address);
  ColPosition = tgetstr ("ch", address);
  AbsPosition = tgetstr ("cm", address);
  CR = tgetstr ("cr", address);
  TS_set_scroll_region = tgetstr ("cs", address);
  TS_set_scroll_region_1 = tgetstr ("cS", address);
  RowPosition = tgetstr ("cv", address);
  TS_del_char = tgetstr ("dc", address);
  TS_del_multi_chars = tgetstr ("DC", address);
  TS_del_line = tgetstr ("dl", address);
  TS_del_multi_lines = tgetstr ("DL", address);
  TS_delete_mode = tgetstr ("dm", address);
  TS_end_delete_mode = tgetstr ("ed", address);
  TS_end_insert_mode = tgetstr ("ei", address);
  Home = tgetstr ("ho", address);
  TS_ins_char = tgetstr ("ic", address);
  TS_ins_multi_chars = tgetstr ("IC", address);
  TS_insert_mode = tgetstr ("im", address);
  TS_pad_inserted_char = tgetstr ("ip", address);
  TS_end_keypad_mode = tgetstr ("ke", address);
  TS_keypad_mode = tgetstr ("ks", address);
  LastLine = tgetstr ("ll", address);
  Right = tgetstr ("nd", address);
  Down = tgetstr ("do", address);
  if (!Down)
    Down = tgetstr ("nl", address); /* Obsolete name for "do" */
#ifdef VMS
  /* VMS puts a carriage return before each linefeed,
     so it is not safe to use linefeeds.  */
  if (Down && Down[0] == '\n' && Down[1] == '\0')
    Down = 0;
#endif /* VMS */
  if (tgetflag ("bs"))
    Left = "\b";		  /* can't possibly be longer! */
  else				  /* (Actually, "bs" is obsolete...) */
    Left = tgetstr ("le", address);
  if (!Left)
    Left = tgetstr ("bc", address); /* Obsolete name for "le" */
  TS_pad_char = tgetstr ("pc", address);
  TS_repeat = tgetstr ("rp", address);
  TS_end_standout_mode = tgetstr ("se", address);
  TS_fwd_scroll = tgetstr ("sf", address);
  TS_standout_mode = tgetstr ("so", address);
  TS_rev_scroll = tgetstr ("sr", address);
  Wcm.cm_tab = tgetstr ("ta", address);
  TS_end_termcap_modes = tgetstr ("te", address);
  TS_termcap_modes = tgetstr ("ti", address);
  Up = tgetstr ("up", address);
  TS_visible_bell = tgetstr ("vb", address);
  TS_end_visual_mode = tgetstr ("ve", address);
  TS_visual_mode = tgetstr ("vs", address);
  TS_set_window = tgetstr ("wi", address);

  AutoWrap = tgetflag ("am");
  memory_below_screen = tgetflag ("db");
  TF_hazeltine = tgetflag ("hz");
  must_write_spaces = tgetflag ("in");
  meta_key = tgetflag ("km") || tgetflag ("MT");
  TF_insmode_motion = tgetflag ("mi");
  TF_standout_motion = tgetflag ("ms");
  TF_underscore = tgetflag ("ul");
  MagicWrap = tgetflag ("xn");
  TF_xs = tgetflag ("xs");
  TF_teleray = tgetflag ("xt");

  /* Get screen size from system, or else from termcap.  */
  get_screen_size (&screen_width, &screen_height);
  if (screen_width <= 0)
    screen_width = tgetnum ("co");
  if (screen_height <= 0)
    screen_height = tgetnum ("li");

  min_padding_speed = tgetnum ("pb");
  TN_standout_width = tgetnum ("sg");
  TabWidth = tgetnum ("tw");

#ifdef VMS
  /* These capabilities commonly use ^J.
     I don't know why, but sending them on VMS does not work;
     it causes following spaces to be lost, sometimes.
     For now, the simplest fix is to avoid using these capabilities ever.  */
  if (Down && Down[0] == '\n')
    Down = 0;
#endif /* VMS */

  if (!TS_bell)
    TS_bell = "\07";

  if (!TS_fwd_scroll)
    TS_fwd_scroll = Down;

  PC = TS_pad_char ? *TS_pad_char : 0;

  if (TabWidth < 0)
    TabWidth = 8;
  
/* Turned off since /etc/termcap seems to have :ta= for most terminals
   and newer termcap doc does not seem to say there is a default.
  if (!Wcm.cm_tab)
    Wcm.cm_tab = "\t";
*/

  if (TS_standout_mode == 0)
    {
      TN_standout_width = tgetnum ("ug");
      TS_end_standout_mode = tgetstr ("ue", address);
      TS_standout_mode = tgetstr ("us", address);
    }

  if (TF_teleray)
    {
      Wcm.cm_tab = 0;
      /* Teleray: most programs want a space in front of TS_standout_mode,
	   but Emacs can do without it (and give one extra column).  */
      TS_standout_mode = "\033RD";
      TN_standout_width = 1;
      /* But that means we cannot rely on ^M to go to column zero! */
      CR = 0;
      /* LF can't be trusted either -- can alter hpos */
      /* if move at column 0 thru a line with TS_standout_mode */
      Down = 0;
    }

  /* Special handling for certain terminal types known to need it */

  if (!strcmp (terminal_type, "supdup"))
    {
      memory_below_screen = 1;
      Wcm.cm_losewrap = 1;
    }
  if (!strncmp (terminal_type, "c10", 3)
      || !strcmp (terminal_type, "perq"))
    {
      /* Supply a makeshift :wi string.
	 This string is not valid in general since it works only
	 for windows starting at the upper left corner;
	 but that is all Emacs uses.

	 This string works only if the screen is using
	 the top of the video memory, because addressing is memory-relative.
	 So first check the :ti string to see if that is true.

	 It would be simpler if the :wi string could go in the termcap
	 entry, but it can't because it is not fully valid.
	 If it were in the termcap entry, it would confuse other programs.  */
      if (!TS_set_window)
	{
	  p = TS_termcap_modes;
	  while (*p && strcmp (p, "\033v  "))
	    p++;
	  if (*p)
	    TS_set_window = "\033v%C %C %C %C ";
	}
      /* Termcap entry often fails to have :in: flag */
      must_write_spaces = 1;
      /* :ti string typically fails to have \E^G! in it */
      /* This limits scope of insert-char to one line.  */
      strcpy (area, TS_termcap_modes);
      strcat (area, "\033\007!");
      TS_termcap_modes = area;
      area += strlen (area) + 1;
      p = AbsPosition;
      /* Change all %+ parameters to %C, to handle
	 values above 96 correctly for the C100.  */
      while (*p)
	{
	  if (p[0] == '%' && p[1] == '+')
	    p[1] = 'C';
	  p++;
	}
    }

  ScreenRows = screen_height;
  ScreenCols = screen_width;
  specified_window = screen_height;

  if (Wcm_init ())	/* can't do cursor motion */
#ifdef VMS
    fatal ("Terminal type \"%s\" is not powerful enough to run Emacs.\n\
It lacks the ability to position the cursor.\n\
If that is not the actual type of terminal you have, use either the\n\
DCL command `SET TERMINAL/DEVICE= ...' for DEC-compatible terminals,\n\
or `define EMACS_TERM \"terminal type\"' for non-DEC terminals.\n",
           terminal_type);
#else
    fatal ("Terminal type \"%s\" is not powerful enough to run Emacs.\n\
It lacks the ability to position the cursor.\n\
If that is not the actual type of terminal you have,\n\
use the C-shell command `setenv TERM ...' to specify the correct type.\n\
It may be necessary to do `unsetenv TERMCAP' as well.\n",
	   terminal_type);
#endif

  delete_in_insert_mode
    = TS_delete_mode && TS_insert_mode
      && !strcmp (TS_delete_mode, TS_insert_mode);

  se_is_so = TS_standout_mode && TS_end_standout_mode
    && !strcmp (TS_standout_mode, TS_end_standout_mode);

  /* Remove width of standout marker from usable width of line */
  if (TN_standout_width > 0)
    screen_width -= TN_standout_width;

  UseTabs = tabs_safe_p () && TabWidth == 8;

  scroll_region_ok = TS_set_window || TS_set_scroll_region
    || TS_set_scroll_region_1;

  line_ins_del_ok = (((TS_ins_line || TS_ins_multi_lines)
		      && (TS_del_line || TS_del_multi_lines))
		     || (scroll_region_ok
			 && TS_fwd_scroll
			 && TS_rev_scroll));

  char_ins_del_ok = ((TS_ins_char || TS_insert_mode ||
		      TS_pad_inserted_char || TS_ins_multi_chars)
		     && (TS_del_char || TS_del_multi_chars));

  fast_clear_end_of_line = TS_clr_line != 0;

  init_baud_rate ();
  if (read_socket_hook)		/* Baudrate is somewhat */
				/* meaningless in this case */
    baud_rate = 9600;
}

/* VARARGS 1 */
fatal (str, arg1, arg2)
     char *str;
{
  fprintf (stderr, "emacs: ");
  fprintf (stderr, str, arg1, arg2);
  fflush (stderr);
  exit (1);
}