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Diffstat (limited to 'tabs.c')
| -rw-r--r-- | tabs.c | 189 |
1 files changed, 189 insertions, 0 deletions
@@ -0,0 +1,189 @@ +/* $XTermId: tabs.c,v 1.43 2012/06/10 16:53:59 tom Exp $ */ + +/* + * Copyright 2000-2011,2012 by Thomas E. Dickey + * + * All Rights Reserved + * + * 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, 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 LISTED COPYRIGHT HOLDER(S) 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. + * + * + * Copyright 1987 by Digital Equipment Corporation, Maynard, Massachusetts. + * + * All Rights Reserved + * + * Permission to use, copy, modify, and distribute this software and its + * documentation for any purpose and without fee is hereby granted, + * provided that the above copyright notice appear in all copies and that + * both that copyright notice and this permission notice appear in + * supporting documentation, and that the name of Digital Equipment + * Corporation not be used in advertising or publicity pertaining to + * distribution of the software without specific, written prior permission. + * + * + * DIGITAL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING + * ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL + * DIGITAL BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR + * ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, + * WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, + * ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS + * SOFTWARE. + */ + +/* tabs.c */ + +#include <xterm.h> +#include <data.h> + +#define TAB_INDEX(n) ((n) >> TAB_BITS_SHIFT) +#define TAB_MASK(n) (1 << ((n) & (TAB_BITS_WIDTH-1))) + +#define SET_TAB(tabs,n) UIntSet(tabs[TAB_INDEX(n)], TAB_MASK(n)) +#define CLR_TAB(tabs,n) UIntClr(tabs[TAB_INDEX(n)], TAB_MASK(n)) +#define TST_TAB(tabs,n) (tabs[TAB_INDEX(n)] & (unsigned) TAB_MASK(n)) + +/* + * places tabstops at only every 8 columns + */ +void +TabReset(Tabs tabs) +{ + int i; + + TabZonk(tabs); + + for (i = 0; i < MAX_TABS; i += 8) + TabSet(tabs, i); +} + +/* + * places a tabstop at col + */ +void +TabSet(Tabs tabs, int col) +{ + if (col >= 0 && col < MAX_TABS) { + SET_TAB(tabs, col); + } +} + +/* + * clears a tabstop at col + */ +void +TabClear(Tabs tabs, int col) +{ + if (col >= 0 && col < MAX_TABS) { + CLR_TAB(tabs, col); + } +} + +/* + * returns the column of the next tabstop + * (or MAX_TABS - 1 if there are no more). + * A tabstop at col is ignored. + */ +static int +TabNext(XtermWidget xw, Tabs tabs, int col) +{ + TScreen *screen = TScreenOf(xw); + + if (screen->curses && screen->do_wrap && (xw->flags & WRAPAROUND)) { + xtermIndex(xw, 1); + set_cur_col(screen, 0); + col = 0; + ResetWrap(screen); + } + for (++col; col < MAX_TABS; ++col) + if (TST_TAB(tabs, col)) + return (col); + + return (MAX_TABS - 1); +} + +/* + * returns the column of the previous tabstop + * (or 0 if there are no more). + * A tabstop at col is ignored. + */ +static int +TabPrev(Tabs tabs, int col) +{ + for (--col; col >= 0; --col) + if ((col < MAX_TABS) && TST_TAB(tabs, col)) + return (col); + + return (0); +} + +/* + * Tab to the next stop, returning true if the cursor moved + */ +Bool +TabToNextStop(XtermWidget xw) +{ + TScreen *screen = TScreenOf(xw); + int saved_column = screen->cur_col; + int next = TabNext(xw, xw->tabs, screen->cur_col); + int max = LineMaxCol(screen, getLineData(screen, screen->cur_row)); + + if (IsLeftRightMode(xw)) + max = TScreenOf(xw)->rgt_marg; + if (next > max) + next = max; + set_cur_col(screen, next); + + return (screen->cur_col > saved_column); +} + +/* + * Tab to the previous stop, returning true if the cursor moved + */ +Bool +TabToPrevStop(XtermWidget xw) +{ + TScreen *screen = TScreenOf(xw); + int saved_column = screen->cur_col; + int next_column = TabPrev(xw->tabs, screen->cur_col); + + if (xw->flags & ORIGIN) { + int left = ScrnLeftMargin(xw); + if (next_column < left) + next_column = left; + } + + set_cur_col(screen, next_column); + + return (screen->cur_col < saved_column); +} + +/* + * clears all tabs + */ +void +TabZonk(Tabs tabs) +{ + memset(tabs, 0, sizeof(*tabs) * TAB_ARRAY_SIZE); +} |