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path: root/nx-X11/programs/xterm/scrollbar.c
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/* $XTermId: scrollbar.c,v 1.116 2005/11/03 13:17:28 tom Exp $ */

/*
 *	$Xorg: scrollbar.c,v 1.4 2000/08/17 19:55:09 cpqbld Exp $
 */

/* $XFree86: xc/programs/xterm/scrollbar.c,v 3.45 2005/11/03 13:17:28 dickey Exp $ */

/*
 * Copyright 2000-2004,2005 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.
 */

#include <xterm.h>

#include <X11/Xatom.h>

#if defined(HAVE_LIB_XAW)
#include <X11/Xaw/Scrollbar.h>
#elif defined(HAVE_LIB_XAW3D)
#include <X11/Xaw3d/Scrollbar.h>
#elif defined(HAVE_LIB_NEXTAW)
#include <X11/neXtaw/Scrollbar.h>
#elif defined(HAVE_LIB_XAWPLUS)
#include <X11/XawPlus/Scrollbar.h>
#endif

#include <data.h>
#include <error.h>
#include <menu.h>
#include <xcharmouse.h>

/*
 * The scrollbar's border overlaps the border of the vt100 window.  If there
 * is no border for the vt100, there can be no border for the scrollbar.
 */
#define SCROLLBAR_BORDER(xw) ((xw)->screen.scrollBarBorder)
#if OPT_TOOLBAR
#define ScrollBarBorder(xw) (BorderWidth(xw) ? SCROLLBAR_BORDER(xw) : 0)
#else
#define ScrollBarBorder(xw) SCROLLBAR_BORDER(xw)
#endif

/* Event handlers */

static void ScrollTextTo PROTO_XT_CALLBACK_ARGS;
static void ScrollTextUpDownBy PROTO_XT_CALLBACK_ARGS;

/* Resize the text window for a terminal screen, modifying the
 * appropriate WM_SIZE_HINTS and taking advantage of bit gravity.
 */
void
DoResizeScreen(XtermWidget xw)
{
    TScreen *screen = &xw->screen;

    int border = 2 * xw->screen.border;
    int min_wide = border + xw->screen.fullVwin.sb_info.width;
    int min_high = border;
#if 1				/* ndef nothack */
    XSizeHints sizehints;
    long supp;
#endif
    XtGeometryResult geomreqresult;
    Dimension reqWidth, reqHeight, repWidth, repHeight;
#ifndef NO_ACTIVE_ICON
    struct _vtwin *saveWin = WhichVWin(screen);

    /* all units here want to be in the normal font units */
    WhichVWin(screen) = &screen->fullVwin;
#endif /* NO_ACTIVE_ICON */

    /*
     * I'm going to try to explain, as I understand it, why we
     * have to do XGetWMNormalHints and XSetWMNormalHints here,
     * although I can't guarantee that I've got it right.
     *
     * In a correctly written toolkit program, the Shell widget
     * parses the user supplied geometry argument.  However,
     * because of the way xterm does things, the VT100 widget does
     * the parsing of the geometry option, not the Shell widget.
     * The result of this is that the Shell widget doesn't set the
     * correct window manager hints, and doesn't know that the
     * user has specified a geometry.
     *
     * The XtVaSetValues call below tells the Shell widget to
     * change its hints.  However, since it's confused about the
     * hints to begin with, it doesn't get them all right when it
     * does the SetValues -- it undoes some of what the VT100
     * widget did when it originally set the hints.
     *
     * To fix this, we do the following:
     *
     * 1. Get the sizehints directly from the window, going around
     *    the (confused) shell widget.
     * 2. Call XtVaSetValues to let the shell widget know which
     *    hints have changed.  Note that this may not even be
     *    necessary, since we're going to right ahead after that
     *    and set the hints ourselves, but it's good to put it
     *    here anyway, so that when we finally do fix the code so
     *    that the Shell does the right thing with hints, we
     *    already have the XtVaSetValues in place.
     * 3. We set the sizehints directly, this fixing up whatever
     *    damage was done by the Shell widget during the
     *    XtVaSetValues.
     *
     * Gross, huh?
     *
     * The correct fix is to redo VTRealize, VTInitialize and
     * VTSetValues so that font processing happens early enough to
     * give back responsibility for the size hints to the Shell.
     *
     * Someday, we hope to have time to do this.  Someday, we hope
     * to have time to completely rewrite xterm.
     */

    TRACE(("DoResizeScreen\n"));

#if 1				/* ndef nothack */
    /*
     * NOTE: the hints and the XtVaSetValues() must match.
     */
    TRACE(("%s@%d -- ", __FILE__, __LINE__));
    TRACE_WM_HINTS(xw);
    if (!XGetWMNormalHints(screen->display, XtWindow(SHELL_OF(xw)),
			   &sizehints, &supp))
	bzero(&sizehints, sizeof(sizehints));

    xtermSizeHints(xw, &sizehints, ScrollbarWidth(screen));

    /* These are obsolete, but old clients may use them */
    sizehints.width = MaxCols(screen) * FontWidth(screen) + sizehints.min_width;
    sizehints.height = MaxRows(screen) * FontHeight(screen) + sizehints.min_height;
#endif

    XSetWMNormalHints(screen->display, XtWindow(SHELL_OF(xw)), &sizehints);

    reqWidth = MaxCols(screen) * FontWidth(screen) + min_wide;
    reqHeight = MaxRows(screen) * FontHeight(screen) + min_high;

    TRACE(("...requesting screensize chars %dx%d, pixels %dx%d\n",
	   MaxRows(screen),
	   MaxCols(screen),
	   reqHeight, reqWidth));

    geomreqresult = XtMakeResizeRequest((Widget) xw, reqWidth, reqHeight,
					&repWidth, &repHeight);
    TRACE(("scrollbar.c XtMakeResizeRequest %dx%d -> %dx%d (status %d)\n",
	   reqHeight, reqWidth,
	   repHeight, repWidth,
	   geomreqresult));

    if (geomreqresult == XtGeometryAlmost) {
	TRACE(("...almost, retry screensize %dx%d\n", repHeight, repWidth));
	geomreqresult = XtMakeResizeRequest((Widget) xw, repWidth,
					    repHeight, NULL, NULL);
    }
#if 1				/* ndef nothack */
    /*
     * XtMakeResizeRequest() has the undesirable side-effect of clearing
     * the window manager's hints, even on a failed request.  This would
     * presumably be fixed if the shell did its own work.
     */
    if (sizehints.flags
	&& repHeight
	&& repWidth) {
	sizehints.height = repHeight;
	sizehints.width = repWidth;
	TRACE_HINTS(&sizehints);
	XSetWMNormalHints(screen->display, VShellWindow, &sizehints);
    }
#endif
    XSync(screen->display, FALSE);	/* synchronize */
    if (XtAppPending(app_con))
	xevents();

#ifndef NO_ACTIVE_ICON
    WhichVWin(screen) = saveWin;
#endif /* NO_ACTIVE_ICON */
}

static Widget
CreateScrollBar(XtermWidget xw, int x, int y, int height)
{
    Widget result;
    Arg args[6];

    XtSetArg(args[0], XtNx, x);
    XtSetArg(args[1], XtNy, y);
    XtSetArg(args[2], XtNheight, height);
    XtSetArg(args[3], XtNreverseVideo, xw->misc.re_verse);
    XtSetArg(args[4], XtNorientation, XtorientVertical);
    XtSetArg(args[5], XtNborderWidth, ScrollBarBorder(xw));

    result = XtCreateWidget("scrollbar", scrollbarWidgetClass,
			    (Widget) xw, args, XtNumber(args));
    XtAddCallback(result, XtNscrollProc, ScrollTextUpDownBy, 0);
    XtAddCallback(result, XtNjumpProc, ScrollTextTo, 0);
    return (result);
}

void
ScrollBarReverseVideo(Widget scrollWidget)
{
    SbInfo *sb = &(term->screen.fullVwin.sb_info);
    Arg args[4];
    Cardinal nargs = XtNumber(args);

    /*
     * Remember the scrollbar's original colors.
     */
    if (sb->rv_cached == False) {
	XtSetArg(args[0], XtNbackground, &(sb->bg));
	XtSetArg(args[1], XtNforeground, &(sb->fg));
	XtSetArg(args[2], XtNborderColor, &(sb->bdr));
	XtSetArg(args[3], XtNborderPixmap, &(sb->bdpix));
	XtGetValues(scrollWidget, args, nargs);
	sb->rv_cached = True;
	sb->rv_active = 0;
    }

    sb->rv_active = !(sb->rv_active);
    XtSetArg(args[!(sb->rv_active)], XtNbackground, sb->bg);
    XtSetArg(args[(sb->rv_active)], XtNforeground, sb->fg);
    nargs = 2;			/* don't set border_pixmap */
    if (sb->bdpix == XtUnspecifiedPixmap) {	/* if not pixmap then pixel */
	if (sb->rv_active) {	/* keep border visible */
	    XtSetArg(args[2], XtNborderColor, args[1].value);
	} else {
	    XtSetArg(args[2], XtNborderColor, sb->bdr);
	}
	nargs = 3;
    }
    XtSetValues(scrollWidget, args, nargs);
}

void
ScrollBarDrawThumb(Widget scrollWidget)
{
    TScreen *screen = &term->screen;
    int thumbTop, thumbHeight, totalHeight;

    thumbTop = screen->topline + screen->savedlines;
    thumbHeight = MaxRows(screen);
    totalHeight = thumbHeight + screen->savedlines;

    XawScrollbarSetThumb(scrollWidget,
			 ((float) thumbTop) / totalHeight,
			 ((float) thumbHeight) / totalHeight);
}

void
ResizeScrollBar(XtermWidget xw)
{
    TScreen *screen = &(xw->screen);

    int height = screen->fullVwin.height + screen->border * 2;
    int width = screen->scrollWidget->core.width;
    int ypos = -ScrollBarBorder(xw);
#ifdef SCROLLBAR_RIGHT
    int xpos = ((term->misc.useRight)
		? (screen->fullVwin.fullwidth -
		   screen->scrollWidget->core.width -
		   BorderWidth(screen->scrollWidget))
		: -ScrollBarBorder(xw));
#else
    int xpos = -ScrollBarBorder(xw);
#endif

    TRACE(("ResizeScrollBar at %d,%d %dx%d\n", ypos, xpos, height, width));

    XtConfigureWidget(
			 screen->scrollWidget,
			 xpos,
			 ypos,
			 width,
			 height,
			 BorderWidth(screen->scrollWidget));
    ScrollBarDrawThumb(screen->scrollWidget);
}

void
WindowScroll(TScreen * screen, int top)
{
    int i, lines;
    int scrolltop, scrollheight, refreshtop;

    if (top < -screen->savedlines)
	top = -screen->savedlines;
    else if (top > 0)
	top = 0;
    if ((i = screen->topline - top) == 0) {
	ScrollBarDrawThumb(screen->scrollWidget);
	return;
    }

    if (screen->cursor_state)
	HideCursor();
    lines = i > 0 ? i : -i;
    if (lines > MaxRows(screen))
	lines = MaxRows(screen);
    scrollheight = screen->max_row - lines + 1;
    if (i > 0)
	refreshtop = scrolltop = 0;
    else {
	scrolltop = lines;
	refreshtop = scrollheight;
    }
    scrolling_copy_area(screen, scrolltop, scrollheight, -i);
    screen->topline = top;

    ScrollSelection(screen, i, True);

    XClearArea(
		  screen->display,
		  VWindow(screen),
		  OriginX(screen),
		  OriginY(screen) + refreshtop * FontHeight(screen),
		  (unsigned) Width(screen),
		  (unsigned) lines * FontHeight(screen),
		  FALSE);
    ScrnRefresh(screen, refreshtop, 0, lines, MaxCols(screen), False);

    ScrollBarDrawThumb(screen->scrollWidget);
}

#ifdef SCROLLBAR_RIGHT
/*
 * Adjust the scrollbar position if we're asked to turn on scrollbars for the
 * first time (or after resizing) after the xterm is already running.  That
 * makes the window grow after we've initially configured the scrollbar's
 * position.  (There must be a better way).
 */
void
updateRightScrollbar(XtermWidget xw)
{
    TScreen *screen = &xw->screen;

    if (xw->misc.useRight
	&& screen->fullVwin.fullwidth < xw->core.width)
	XtVaSetValues(screen->scrollWidget,
		      XtNx, screen->fullVwin.fullwidth - BorderWidth(screen->scrollWidget),
		      (XtPointer) 0);
}

#endif
void
ScrollBarOn(XtermWidget xw, int init, int doalloc)
{
    TScreen *screen = &xw->screen;
    int i, j, k;

    if (screen->fullVwin.sb_info.width || IsIcon(screen))
	return;

    TRACE(("ScrollBarOn\n"));
    if (init) {			/* then create it only */
	if (screen->scrollWidget == 0) {
	    /* make it a dummy size and resize later */
	    screen->scrollWidget = CreateScrollBar(xw,
						   -ScrollBarBorder(xw),
						   -ScrollBarBorder(xw),
						   5);
	    if (screen->scrollWidget == NULL) {
		Bell(XkbBI_MinorError, 0);
	    }
	}
    } else if (!screen->scrollWidget || !XtIsRealized((Widget) term)) {
	Bell(XkbBI_MinorError, 0);
	Bell(XkbBI_MinorError, 0);
    } else {

	if (doalloc && screen->allbuf) {
	    /* FIXME: this is not integrated well with Allocate */
	    if ((screen->allbuf =
		 TypeRealloc(ScrnPtr,
			     MAX_PTRS * (screen->max_row + 2 + screen->savelines),
			     screen->visbuf)) == NULL) {
		SysError(ERROR_SBRALLOC);
	    }
	    screen->visbuf = &screen->allbuf[MAX_PTRS * screen->savelines];
	    memmove((char *) screen->visbuf, (char *) screen->allbuf,
		    MAX_PTRS * (screen->max_row + 2) * sizeof(char *));
	    for (i = k = 0; i < screen->savelines; i++) {
		k += BUF_HEAD;
		for (j = BUF_HEAD; j < MAX_PTRS; j++) {
		    if ((screen->allbuf[k++] =
			 TypeCallocN(Char, (unsigned) MaxCols(screen))
			) == NULL)
			SysError(ERROR_SBRALLOC2);
		}
	    }
	}

	ResizeScrollBar(xw);
	xtermAddInput(screen->scrollWidget);
	XtRealizeWidget(screen->scrollWidget);
	TRACE_TRANS("scrollbar", screen->scrollWidget);

	screen->fullVwin.sb_info.rv_cached = False;

	screen->fullVwin.sb_info.width = (screen->scrollWidget->core.width
					  + BorderWidth(screen->scrollWidget));

	TRACE(("setting scrollbar width %d = %d + %d\n",
	       screen->fullVwin.sb_info.width,
	       screen->scrollWidget->core.width,
	       BorderWidth(screen->scrollWidget)));

	ScrollBarDrawThumb(screen->scrollWidget);
	DoResizeScreen(xw);

#ifdef SCROLLBAR_RIGHT
	updateRightScrollbar(term);
#endif

	XtMapWidget(screen->scrollWidget);
	update_scrollbar();
	if (screen->visbuf) {
	    XClearWindow(screen->display, XtWindow(term));
	    Redraw();
	}
    }
}

void
ScrollBarOff(TScreen * screen)
{
    if (!screen->fullVwin.sb_info.width || IsIcon(screen))
	return;

    TRACE(("ScrollBarOff\n"));
    if (XtIsRealized((Widget) term)) {
	XtUnmapWidget(screen->scrollWidget);
	screen->fullVwin.sb_info.width = 0;
	DoResizeScreen(term);
	update_scrollbar();
	if (screen->visbuf) {
	    XClearWindow(screen->display, XtWindow(term));
	    Redraw();
	}
    } else {
	Bell(XkbBI_MinorError, 0);
    }
}

/*
 * Toggle the visibility of the scrollbars.
 */
void
ToggleScrollBar(XtermWidget w)
{
    TScreen *screen = &w->screen;

    if (IsIcon(screen)) {
	Bell(XkbBI_MinorError, 0);
    } else {
	TRACE(("ToggleScrollBar{{\n"));
	if (screen->fullVwin.sb_info.width) {
	    ScrollBarOff(screen);
	} else {
	    ScrollBarOn(w, FALSE, FALSE);
	}
	update_scrollbar();
	TRACE(("...ToggleScrollBar}}\n"));
    }
}

/*ARGSUSED*/
static void
ScrollTextTo(
		Widget scrollbarWidget GCC_UNUSED,
		XtPointer client_data GCC_UNUSED,
		XtPointer call_data)
{
    float *topPercent = (float *) call_data;
    TScreen *screen = &term->screen;
    int thumbTop;		/* relative to first saved line */
    int newTopLine;

    /*
     * screen->savedlines : Number of offscreen text lines,
     * MaxRows(screen)    : Number of onscreen  text lines,
     * screen->topline    : -Number of lines above the last screen->max_row+1 lines
     */

    thumbTop = (int) (*topPercent * (screen->savedlines + MaxRows(screen)));
    newTopLine = thumbTop - screen->savedlines;
    WindowScroll(screen, newTopLine);
}

/*ARGSUSED*/
static void
ScrollTextUpDownBy(
		      Widget scrollbarWidget GCC_UNUSED,
		      XtPointer client_data GCC_UNUSED,
		      XtPointer call_data)
{
    long pixels = (long) call_data;

    TScreen *screen = &term->screen;
    int rowOnScreen, newTopLine;

    rowOnScreen = pixels / FontHeight(screen);
    if (rowOnScreen == 0) {
	if (pixels < 0)
	    rowOnScreen = -1;
	else if (pixels > 0)
	    rowOnScreen = 1;
    }
    newTopLine = screen->topline + rowOnScreen;
    WindowScroll(screen, newTopLine);
}

/*
 * assume that b is lower case and allow plural
 */
static int
specialcmplowerwiths(char *a, char *b, int *modifier)
{
    char ca, cb;

    *modifier = 0;
    if (!a || !b)
	return 0;

    while (1) {
	ca = char2lower(*a);
	cb = *b;
	if (ca != cb || ca == '\0')
	    break;		/* if not eq else both nul */
	a++, b++;
    }
    if (cb != '\0')
	return 0;

    if (ca == 's')
	ca = *++a;

    switch (ca) {
    case '+':
    case '-':
	*modifier = (ca == '-' ? -1 : 1) * atoi(a + 1);
	return 1;

    case '\0':
	return 1;

    default:
	return 0;
    }
}

static long
params_to_pixels(TScreen * screen, String * params, Cardinal n)
{
    int mult = 1;
    char *s;
    int modifier;

    switch (n > 2 ? 2 : n) {
    case 2:
	s = params[1];
	if (specialcmplowerwiths(s, "page", &modifier)) {
	    mult = (MaxRows(screen) + modifier) * FontHeight(screen);
	} else if (specialcmplowerwiths(s, "halfpage", &modifier)) {
	    mult = ((MaxRows(screen) + modifier) * FontHeight(screen)) / 2;
	} else if (specialcmplowerwiths(s, "pixel", &modifier)) {
	    mult = 1;
	} else {
	    /* else assume that it is Line */
	    mult = FontHeight(screen);
	}
	mult *= atoi(params[0]);
	break;
    case 1:
	mult = atoi(params[0]) * FontHeight(screen);	/* lines */
	break;
    default:
	mult = screen->scrolllines * FontHeight(screen);
	break;
    }
    return mult;
}

static long
AmountToScroll(Widget gw, String * params, Cardinal nparams)
{
    if (gw != 0) {
	if (IsXtermWidget(gw)) {
	    TScreen *screen = &((XtermWidget) gw)->screen;
	    if (nparams > 2
		&& screen->send_mouse_pos != MOUSE_OFF)
		return 0;
	    return params_to_pixels(screen, params, nparams);
	} else {
	    /*
	     * This may have been the scrollbar widget.  Try its parent, which
	     * would be the VT100 widget.
	     */
	    return AmountToScroll(XtParent(gw), params, nparams);
	}
    }
    return 0;
}

/*ARGSUSED*/
void
HandleScrollForward(
		       Widget gw,
		       XEvent * event GCC_UNUSED,
		       String * params,
		       Cardinal *nparams)
{
    long amount;

    if ((amount = AmountToScroll(gw, params, *nparams)) != 0) {
	ScrollTextUpDownBy(gw, (XtPointer) 0, (XtPointer) amount);
    }
}

/*ARGSUSED*/
void
HandleScrollBack(
		    Widget gw,
		    XEvent * event GCC_UNUSED,
		    String * params,
		    Cardinal *nparams)
{
    long amount;

    if ((amount = -AmountToScroll(gw, params, *nparams)) != 0) {
	ScrollTextUpDownBy(gw, (XtPointer) 0, (XtPointer) amount);
    }
}