tty_update.c

ncurses-5.4 需要的就来下把 一定会有用的哦

/****************************************************************************
 * Copyright (c) 1998-2003,2004 Free Software Foundation, Inc.              *
 *                                                                          *
 * Permission is hereby granted, free of charge, to any person obtaining a  *
 * copy of this software and associated documentation files (the            *
 * "Software"), to deal in the Software without restriction, including      *
 * without limitation the rights to use, copy, modify, merge, publish,      *
 * distribute, distribute with modifications, sublicense, and/or sell       *
 * copies of the Software, and to permit persons to whom the Software is    *
 * furnished to do so, subject to the following conditions:                 *
 *                                                                          *
 * The above copyright notice and this permission notice shall be included  *
 * in all copies or substantial portions of the Software.                   *
 *                                                                          *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
 * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
 *                                                                          *
 * Except as contained in this notice, the name(s) of the above copyright   *
 * holders shall not be used in advertising or otherwise to promote the     *
 * sale, use or other dealings in this Software without prior written       *
 * authorization.                                                           *
 ****************************************************************************/

/****************************************************************************
 *  Author: Zeyd M. Ben-Halim <[e-mail]> 1992,1995               *
 *     and: Eric S. Raymond <[e-mail]>                         *
 *     and: Thomas E. Dickey 1996-2004                                      *
 ****************************************************************************/

/*-----------------------------------------------------------------
 *
 *	lib_doupdate.c
 *
 * 	The routine doupdate() and its dependents.
 * 	All physical output is concentrated here (except _nc_outch()
  *	in lib_tputs.c).
 *
 *-----------------------------------------------------------------*/

#include <curses.priv.h>

#ifdef __BEOS__
#undef false
#undef true
#include <OS.h>
#endif

#if defined(TRACE) && HAVE_SYS_TIMES_H && HAVE_TIMES
#define USE_TRACE_TIMES 1
#else
#define USE_TRACE_TIMES 0
#endif

#if HAVE_SYS_TIME_H && HAVE_SYS_TIME_SELECT
#include <sys/time.h>
#endif

#if USE_TRACE_TIMES
#include <sys/times.h>
#endif

#if USE_FUNC_POLL
#elif HAVE_SELECT
#if HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif
#endif

#include <ctype.h>
#include <term.h>

MODULE_ID("$Id: tty_update.c,v 1.205 2004/02/07 18:02:42 tom Exp $")

/*
 * This define controls the line-breakout optimization.  Every once in a
 * while during screen refresh, we want to check for input and abort the
 * update if there's some waiting.  CHECK_INTERVAL controls the number of
 * changed lines to be emitted between input checks.
 *
 * Note: Input-check-and-abort is no longer done if the screen is being
 * updated from scratch.  This is a feature, not a bug.
 */
#define CHECK_INTERVAL	5

#define FILL_BCE() (SP->_coloron && !SP->_default_color && !back_color_erase)

/*
 * Enable checking to see if doupdate and friends are tracking the true
 * cursor position correctly.  NOTE: this is a debugging hack which will
 * work ONLY on ANSI-compatible terminals!
 */
/* #define POSITION_DEBUG */

static inline NCURSES_CH_T ClrBlank(WINDOW *win);
static int ClrBottom(int total);
static void ClearScreen(NCURSES_CH_T blank);
static void ClrUpdate(void);
static void DelChar(int count);
static void InsStr(NCURSES_CH_T * line, int count);
static void TransformLine(int const lineno);

#ifdef POSITION_DEBUG
/****************************************************************************
 *
 * Debugging code.  Only works on ANSI-standard terminals.
 *
 ****************************************************************************/

static void
position_check(int expected_y, int expected_x, char *legend)
/* check to see if the real cursor position matches the virtual */
{
    char buf[20];
    char *s;
    int y, x;

    if (!_nc_tracing || (expected_y < 0 && expected_x < 0))
	return;

    _nc_flush();
    memset(buf, '\0', sizeof(buf));
    putp("\033[6n");		/* only works on ANSI-compatibles */
    _nc_flush();
    *(s = buf) = 0;
    do {
	int ask = sizeof(buf) - 1 - (s - buf);
	int got = read(0, s, ask);
	if (got == 0)
	    break;
	s += got;
    } while (strchr(buf, 'R') == 0);
    _tracef("probe returned %s", _nc_visbuf(buf));

    /* try to interpret as a position report */
    if (sscanf(buf, "\033[%d;%dR", &y, &x) != 2) {
	_tracef("position probe failed in %s", legend);
    } else {
	if (expected_x < 0)
	    expected_x = x - 1;
	if (expected_y < 0)
	    expected_y = y - 1;
	if (y - 1 != expected_y || x - 1 != expected_x) {
	    beep();
	    tputs(tparm("\033[%d;%dH", expected_y + 1, expected_x + 1), 1, _nc_outch);
	    _tracef("position seen (%d, %d) doesn't match expected one (%d, %d) in %s",
		    y - 1, x - 1, expected_y, expected_x, legend);
	} else {
	    _tracef("position matches OK in %s", legend);
	}
    }
}
#else
#define position_check(expected_y, expected_x, legend)	/* nothing */
#endif /* POSITION_DEBUG */

/****************************************************************************
 *
 * Optimized update code
 *
 ****************************************************************************/

static inline void
GoTo(int const row, int const col)
{
    TR(TRACE_MOVE, ("GoTo(%d, %d) from (%d, %d)",
		    row, col, SP->_cursrow, SP->_curscol));

    position_check(SP->_cursrow, SP->_curscol, "GoTo");

    mvcur(SP->_cursrow, SP->_curscol, row, col);
    position_check(SP->_cursrow, SP->_curscol, "GoTo2");
}

static inline void
PutAttrChar(CARG_CH_T ch)
{
    int chlen = 1;
    NCURSES_CH_T my_ch;
    PUTC_DATA;
    NCURSES_CH_T tilde;
    NCURSES_ATTR_T attr = AttrOfD(ch);

    TR(TRACE_CHARPUT, ("PutAttrChar(%s) at (%d, %d)",
		       _tracech_t(ch),
		       SP->_cursrow, SP->_curscol));
#if USE_WIDEC_SUPPORT
    /*
     * If this is not a valid character, there is nothing more to do.
     */
    if (isnac(CHDEREF(ch)))
	return;
    /*
     * Determine the number of character cells which the 'ch' value will use
     * on the screen.  It should be at least one.
     */
    if ((chlen = wcwidth(CharOf(CHDEREF(ch)))) <= 0) {
	static NCURSES_CH_T blank = NewChar(BLANK_TEXT);

	if (isprint(CharOf(CHDEREF(ch)))
	    || (SP->_posix_locale && CharOf(CHDEREF(ch)) >= 160)) {
	    ;
	} else {
	    ch = CHREF(blank);
	    TR(TRACE_CHARPUT, ("forced to blank"));
	}
	chlen = 1;
    }
#endif

    if ((attr & A_ALTCHARSET)
	&& SP->_acs_map != 0
	&& CharOfD(ch) < ACS_LEN) {
	my_ch = CHDEREF(ch);	/* work around const param */
#if USE_WIDEC_SUPPORT
	/*
	 * This is crude & ugly, but works most of the time.  It checks if the
	 * acs_chars string specified that we have a mapping for this
	 * character, and uses the wide-character mapping when we expect the
	 * normal one to be broken (by mis-design ;-).
	 */
	if (SP->_screen_acs_fix
	    && SP->_acs_map[CharOf(my_ch)] & A_ALTCHARSET) {
	    attr &= ~(A_ALTCHARSET);
	    my_ch = _nc_wacs[CharOf(my_ch)];
	}
#endif
	if (attr & A_ALTCHARSET) {
	    chtype temp = UChar(SP->_acs_map[CharOfD(ch)]);
	    if (temp != 0)
		SetChar(my_ch, temp, attr);
	    RemAttr(my_ch, A_ALTCHARSET);
	}
	ch = CHREF(my_ch);
    }
    if (tilde_glitch && (CharOfD(ch) == L('~'))) {
	SetChar(tilde, L('`'), attr);
	ch = CHREF(tilde);
    }

    UpdateAttrs(attr);
#if !USE_WIDEC_SUPPORT
    /* FIXME - we do this special case for signal handling, should see how to
     * make it work for wide characters.
     */
    if (SP->_outch != 0) {
	SP->_outch(UChar(ch));
    } else
#endif
    {
	PUTC(CHDEREF(ch), SP->_ofp);	/* macro's fastest... */
	TRACE_OUTCHARS(1);
    }
    SP->_curscol += chlen;
    if (char_padding) {
	TPUTS_TRACE("char_padding");
	putp(char_padding);
    }
}

static bool
check_pending(void)
/* check for pending input */
{
    bool have_pending = FALSE;

    /*
     * Only carry out this check when the flag is zero, otherwise we'll
     * have the refreshing slow down drastically (or stop) if there's an
     * unread character available.
     */
    if (SP->_fifohold != 0)
	return FALSE;

    if (SP->_checkfd >= 0) {
#if USE_FUNC_POLL
	struct pollfd fds[1];
	fds[0].fd = SP->_checkfd;
	fds[0].events = POLLIN;
	if (poll(fds, 1, 0) > 0) {
	    have_pending = TRUE;
	}
#elif defined(__BEOS__)
	/*
	 * BeOS's select() is declared in socket.h, so the configure script does
	 * not see it.  That's just as well, since that function works only for
	 * sockets.  This (using snooze and ioctl) was distilled from Be's patch
	 * for ncurses which uses a separate thread to simulate select().
	 *
	 * FIXME: the return values from the ioctl aren't very clear if we get
	 * interrupted.
	 */
	int n = 0;
	int howmany = ioctl(0, 'ichr', &n);
	if (howmany >= 0 && n > 0) {
	    have_pending = TRUE;
	}
#elif HAVE_SELECT
	fd_set fdset;
	struct timeval ktimeout;

	ktimeout.tv_sec =
	    ktimeout.tv_usec = 0;

	FD_ZERO(&fdset);
	FD_SET(SP->_checkfd, &fdset);
	if (select(SP->_checkfd + 1, &fdset, NULL, NULL, &ktimeout) != 0) {
	    have_pending = TRUE;
	}
#endif
    }
    if (have_pending) {
	SP->_fifohold = 5;
	_nc_flush();
    }
    return FALSE;
}

/* put char at lower right corner */
static void
PutCharLR(const ARG_CH_T ch)
{
    if (!auto_right_margin) {
	/* we can put the char directly */
	PutAttrChar(ch);
    } else if (enter_am_mode && exit_am_mode) {
	/* we can suppress automargin */
	TPUTS_TRACE("exit_am_mode");
	putp(exit_am_mode);

	PutAttrChar(ch);
	SP->_curscol--;
	position_check(SP->_cursrow, SP->_curscol, "exit_am_mode");

	TPUTS_TRACE("enter_am_mode");
	putp(enter_am_mode);
    } else if ((enter_insert_mode && exit_insert_mode)
	       || insert_character || parm_ich) {
	GoTo(screen_lines - 1, screen_columns - 2);
	PutAttrChar(ch);
	GoTo(screen_lines - 1, screen_columns - 2);
	InsStr(newscr->_line[screen_lines - 1].text + screen_columns - 2, 1);
    }
}

static void
wrap_cursor(void)
{
    if (eat_newline_glitch) {
	/*
	 * xenl can manifest two different ways.  The vt100
	 * way is that, when you'd expect the cursor to wrap,
	 * it stays hung at the right margin (on top of the
	 * character just emitted) and doesn't wrap until the
	 * *next* graphic char is emitted.  The c100 way is
	 * to ignore LF received just after an am wrap.
	 *
	 * An aggressive way to handle this would be to
	 * emit CR/LF after the char and then assume the wrap
	 * is done, you're on the first position of the next
	 * line, and the terminal out of its weird state.
	 * Here it's safe to just tell the code that the
	 * cursor is in hyperspace and let the next mvcur()
	 * call straighten things out.
	 */
	SP->_curscol = -1;
	SP->_cursrow = -1;
    } else if (auto_right_margin) {
	SP->_curscol = 0;
	SP->_cursrow++;
    } else {
	SP->_curscol--;
    }
    position_check(SP->_cursrow, SP->_curscol, "wrap_cursor");
}

static inline void
PutChar(const ARG_CH_T ch)
/* insert character, handling automargin stuff */
{
    if (SP->_cursrow == screen_lines - 1 && SP->_curscol == screen_columns - 1)
	PutCharLR(ch);
    else
	PutAttrChar(ch);

    if (SP->_curscol >= screen_columns)
	wrap_cursor();

    position_check(SP->_cursrow, SP->_curscol, "PutChar");
}

/*
 * Check whether the given character can be output by clearing commands.  This
 * includes test for being a space and not including any 'bad' attributes, such
 * as A_REVERSE.  All attribute flags which don't affect appearance of a space
 * or can be output by clearing (A_COLOR in case of bce-terminal) are excluded.
 */
static inline bool
can_clear_with(ARG_CH_T ch)
{
    if (!back_color_erase && SP->_coloron) {
#if NCURSES_EXT_FUNCS
	if (!SP->_default_color)
	    return FALSE;
	if (SP->_default_fg != C_MASK || SP->_default_bg != C_MASK)
	    return FALSE;
	if (AttrOfD(ch) & A_COLOR) {
	    short fg, bg;
	    pair_content(PAIR_NUMBER(AttrOfD(ch)), &fg, &bg);
	    if (fg != C_MASK || bg != C_MASK)
		return FALSE;
	}
#else
	if (AttrOfD(ch) & A_COLOR)
	    return FALSE;
#endif
    }
    return (ISBLANK(CHDEREF(ch)) &&
	    (AttrOfD(ch) & ~(NONBLANK_ATTR | A_COLOR)) == BLANK_ATTR);
}

/*
 * Issue a given span of characters from an array.
 * Must be functionally equivalent to:
 *	for (i = 0; i < num; i++)
 *	    PutChar(ntext[i]);
 * but can leave the cursor positioned at the middle of the interval.
 *
 * Returns: 0 - cursor is at the end of interval
 *	    1 - cursor is somewhere in the middle
 *
 * This code is optimized using ech and rep.
 */
static int
EmitRange(const NCURSES_CH_T * ntext, int num)
{
    int i;

    if (erase_chars || repeat_char) {
	while (num > 0) {
	    int runcount;
	    NCURSES_CH_T ntext0;

	    while (num > 1 && !CharEq(ntext[0], ntext[1])) {
		PutChar(CHREF(ntext[0]));
		ntext++;
		num--;
	    }
	    ntext0 = ntext[0];
	    if (num == 1) {
		PutChar(CHREF(ntext0));
		return 0;
	    }
	    runcount = 2;

	    while (runcount < num && CharEq(ntext[runcount], ntext0))
		runcount++;

	    /*
	     * The cost expression in the middle isn't exactly right.
	     * _cup_ch_cost is an upper bound on the cost for moving to the
	     * end of the erased area, but not the cost itself (which we
	     * can't compute without emitting the move).  This may result
	     * in erase_chars not getting used in some situations for
	     * which it would be marginally advantageous.
	     */
	    if (erase_chars
		&& runcount > SP->_ech_cost + SP->_cup_ch_cost