vim、SGRパッチ適用後のDA2チェック部分のロジック

vim_check_da2_sgr.txt

#ifdef FEAT_TERMRESPONSE
	if (key_name[0] == NUL
	    /* URXVT mouse uses <ESC>[#;#;#M, but we are matching <ESC>[ */
	    || key_name[0] == KS_URXVT_MOUSE
	    || key_name[0] == KS_SGR_MOUSE)
	{
	    /* Check for xterm version string: "<Esc>[>{x};{vers};{y}c".  Also
	     * eat other possible responses to t_RV, rxvt returns
	     * "<Esc>[?1;2c".  Also accept CSI instead of <Esc>[.
	     * mrxvt has been reported to have "+" in the version. Assume
	     * the escape sequence ends with a letter or one of "{|}~". */
	    if (*T_CRV != NUL && ((tp[0] == ESC && tp[1] == '[' && len >= 3)
					       || (tp[0] == CSI && len >= 2)))
	    {
		j = 0;
		extra = 0;
		for (i = 2 + (tp[0] != CSI); i < len
				&& !(tp[i] >= '{' && tp[i] <= '~')
				&& !ASCII_ISALPHA(tp[i]); ++i)
		    if (tp[i] == ';' && ++j == 1)
			extra = atoi((char *)tp + i + 1);
		if (i == len)
		    return -1;		/* not enough characters */

		/* eat it when at least one digit and ending in 'c' */
		if (i > 2 + (tp[0] != CSI) && tp[i] == 'c')
		{
		    crv_status = CRV_GOT;

		    /* If this code starts with CSI, you can bet that the
		     * terminal uses 8-bit codes. */
		    if (tp[0] == CSI)
			switch_to_8bit();

		    /* rxvt sends its version number: "20703" is 2.7.3.
		     * Ignore it for when the user has set 'term' to xterm,
		     * even though it's an rxvt. */
		    if (extra > 20000)
			extra = 0;

		    if (tp[1 + (tp[0] != CSI)] == '>' && j == 2)
		    {
# ifdef TTYM_SGR
			if (extra >= 277
# ifdef TTYM_URXVT
				&& ttym_flags != TTYM_URXVT
# endif
				)
			    set_option_value((char_u *)"ttym", 0L,
						       (char_u *)"sgr", 0);
                        else
# endif
			/* if xterm version >= 95 use mouse dragging */
			if (extra >= 95
# ifdef TTYM_URXVT
				&& ttym_flags != TTYM_URXVT
# endif
				)
			    set_option_value((char_u *)"ttym", 0L,
						       (char_u *)"xterm2", 0);
			/* if xterm version >= 141 try to get termcap codes */
			if (extra >= 141)
			{
			    check_for_codes = TRUE;
			    need_gather = TRUE;
			    req_codes_from_term();
			}
		    }
# ifdef FEAT_EVAL
		    set_vim_var_string(VV_TERMRESPONSE, tp, i + 1);
# endif
# ifdef FEAT_AUTOCMD
		    apply_autocmds(EVENT_TERMRESPONSE,
						   NULL, NULL, FALSE, curbuf);
# endif
		    key_name[0] = (int)KS_EXTRA;
		    key_name[1] = (int)KE_IGNORE;
		    slen = i + 1;
		}
	    }

	    /* Check for '<Esc>P1+r<hex bytes><Esc>\'.  A "0" instead of the
	     * "1" means an invalid request. */
	    else if (check_for_codes
		    && ((tp[0] == ESC && tp[1] == 'P' && len >= 2)
			|| tp[0] == DCS))
	    {
		j = 1 + (tp[0] != DCS);
		for (i = j; i < len; ++i)
		    if ((tp[i] == ESC && tp[i + 1] == '\\' && i + 1 < len)
			    || tp[i] == STERM)
		    {
			if (i - j >= 3 && tp[j + 1] == '+' && tp[j + 2] == 'r')
			    got_code_from_term(tp + j, i);
			key_name[0] = (int)KS_EXTRA;
			key_name[1] = (int)KE_IGNORE;
			slen = i + 1 + (tp[i] == ESC);
			break;
		    }

		if (i == len)
		    return -1;		/* not enough characters */
	    }
	}
#endif