Import Micropolis from http://www.donhopkins.com/home/micropolis/

[micropolis] / src / tk / tkbutton.c

/* 
 * tkButton.c --
 *
 *      This module implements a collection of button-like
 *      widgets for the Tk toolkit.  The widgets implemented
 *      include labels, buttons, check buttons, and radio
 *      buttons.
 *
 * Copyright 1990-1992 Regents of the University of California.
 * 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.  The University of California
 * makes no representations about the suitability of this
 * software for any purpose.  It is provided "as is" without
 * express or implied warranty.
 */

#ifndef lint
static char rcsid[] = "$Header: /user6/ouster/wish/RCS/tkButton.c,v 1.69 92/08/21 11:42:47 ouster Exp $ SPRITE (Berkeley)";
#endif

#include "default.h"
#include "tkconfig.h"
#include "tkint.h"

#include <assert.h>

/*
 * A data structure of the following type is kept for each
 * widget managed by this file:
 */

typedef struct {
    Tk_Window tkwin;            /* Window that embodies the button.  NULL
                                 * means that the window has been destroyed. */
    Tcl_Interp *interp;         /* Interpreter associated with button. */
    int type;                   /* Type of widget:  restricts operations
                                 * that may be performed on widget.  See
                                 * below for possible values. */

    /*
     * Information about what's in the button.
     */

    char *text;                 /* Text to display in button (malloc'ed)
                                 * or NULL. */
    int textLength;             /* # of characters in text. */
    char *textVarName;          /* Name of variable (malloc'ed) or NULL.
                                 * If non-NULL, button displays the contents
                                 * of this variable. */
    Pixmap bitmap;              /* Bitmap to display or None.  If not None
                                 * then text and textVar are ignored. */

    /*
     * Information used when displaying widget:
     */

    Tk_Uid state;               /* State of button for display purposes:
                                 * normal, active, or disabled. */
    Tk_3DBorder normalBorder;   /* Structure used to draw 3-D
                                 * border and background when window
                                 * isn't active.  NULL means no such
                                 * border exists. */
    Tk_3DBorder activeBorder;   /* Structure used to draw 3-D
                                 * border and background when window
                                 * is active.  NULL means no such
                                 * border exists. */
    int borderWidth;            /* Width of border. */
    int relief;                 /* 3-d effect: TK_RELIEF_RAISED, etc. */
    XFontStruct *fontPtr;       /* Information about text font, or NULL. */
    XColor *normalFg;           /* Foreground color in normal mode. */
    XColor *activeFg;           /* Foreground color in active mode.  NULL
                                 * means use normalFg instead. */
    XColor *disabledFg;         /* Foreground color when disabled.  NULL
                                 * means use normalFg with a 50% stipple
                                 * instead. */
    GC normalTextGC;            /* GC for drawing text in normal mode.  Also
                                 * used to copy from off-screen pixmap onto
                                 * screen. */
    GC activeTextGC;            /* GC for drawing text in active mode (NULL
                                 * means use normalTextGC). */
    Pixmap gray;                /* Pixmap for displaying disabled text if
                                 * disabledFg is NULL. */
    GC disabledGC;              /* Used to produce disabled effect.  If
                                 * disabledFg isn't NULL, this GC is used to
                                 * draw button text or icon.  Otherwise
                                 * text or icon is drawn with normalGC and
                                 * this GC is used to stipple background
                                 * across it. */
    int leftBearing;            /* Amount text sticks left from its origin,
                                 * in pixels. */
    int rightBearing;           /* Amount text sticks right from its origin. */
    int width, height;          /* If > 0, these specify dimensions to request
                                 * for window, in characters for text and in
                                 * pixels for bitmaps.  In this case the actual
                                 * size of the text string or bitmap is
                                 * ignored in computing desired window size. */
    int padX, padY;             /* Extra space around text or bitmap (pixels
                                 * on each side). */
    Tk_Anchor anchor;           /* Where text/bitmap should be displayed
                                 * inside button region. */
    XColor *selectorFg;         /* Color for selector. */
    GC selectorGC;              /* For drawing highlight when this button
                                 * is in selected state. */
    int selectorSpace;          /* Horizontal space (in pixels) allocated for
                                 * display of selector. */
    int selectorDiameter;       /* Diameter of selector, in pixels. */

    /*
     * For check and radio buttons, the fields below are used
     * to manage the variable indicating the button's state.
     */

    char *selVarName;           /* Name of variable used to control selected
                                 * state of button.  Malloc'ed (if
                                 * not NULL). */
    char *onValue;              /* Value to store in variable when
                                 * this button is selected.  Malloc'ed (if
                                 * not NULL). */
    char *offValue;             /* Value to store in variable when this
                                 * button isn't selected.  Malloc'ed
                                 * (if not NULL).  Valid only for check
                                 * buttons. */

    /*
     * Miscellaneous information:
     */

    Cursor cursor;              /* Current cursor for window, or None. */
    char *command;              /* Command to execute when button is
                                 * invoked; valid for buttons only.
                                 * If not NULL, it's malloc-ed. */
    int flags;                  /* Various flags;  see below for
                                 * definitions. */
    Tk_TimerToken updateTimerToken; /* Added by Don to optimize rapid 
                                     * updates. */
} Button;

/*
 * Possible "type" values for buttons.  These are the kinds of
 * widgets supported by this file.  The ordering of the type
 * numbers is significant:  greater means more features and is
 * used in the code.
 */

#define TYPE_LABEL              0
#define TYPE_BUTTON             1
#define TYPE_CHECK_BUTTON       2
#define TYPE_RADIO_BUTTON       3

/*
 * Class names for buttons, indexed by one of the type values above.
 */

static char *classNames[] = {"Label", "Button", "CheckButton", "RadioButton"};

/*
 * Flag bits for buttons:
 *
 * REDRAW_PENDING:              Non-zero means a DoWhenIdle handler
 *                              has already been queued to redraw
 *                              this window.
 * SELECTED:                    Non-zero means this button is selected,
 *                              so special highlight should be drawn.
 */

#define REDRAW_PENDING          1
#define SELECTED                2

/*
 * Mask values used to selectively enable entries in the
 * configuration specs:
 */

#define LABEL_MASK              TK_CONFIG_USER_BIT
#define BUTTON_MASK             TK_CONFIG_USER_BIT << 1
#define CHECK_BUTTON_MASK       TK_CONFIG_USER_BIT << 2
#define RADIO_BUTTON_MASK       TK_CONFIG_USER_BIT << 3
#define ALL_MASK                (LABEL_MASK | BUTTON_MASK \
        | CHECK_BUTTON_MASK | RADIO_BUTTON_MASK)

static int configFlags[] = {LABEL_MASK, BUTTON_MASK,
        CHECK_BUTTON_MASK, RADIO_BUTTON_MASK};
/*
 * Information used for parsing configuration specs:
 */

static Tk_ConfigSpec configSpecs[] = {
    {TK_CONFIG_BORDER, "-activebackground", "activeBackground", "Foreground",
        DEF_BUTTON_ACTIVE_BG_COLOR, Tk_Offset(Button, activeBorder),
        BUTTON_MASK|CHECK_BUTTON_MASK|RADIO_BUTTON_MASK
        |TK_CONFIG_COLOR_ONLY},
    {TK_CONFIG_BORDER, "-activebackground", "activeBackground", "Foreground",
        DEF_BUTTON_ACTIVE_BG_MONO, Tk_Offset(Button, activeBorder),
        BUTTON_MASK|CHECK_BUTTON_MASK|RADIO_BUTTON_MASK
        |TK_CONFIG_MONO_ONLY},
    {TK_CONFIG_COLOR, "-activeforeground", "activeForeground", "Background",
        DEF_BUTTON_ACTIVE_FG_COLOR, Tk_Offset(Button, activeFg), 
        BUTTON_MASK|CHECK_BUTTON_MASK|RADIO_BUTTON_MASK
        |TK_CONFIG_COLOR_ONLY},
    {TK_CONFIG_COLOR, "-activeforeground", "activeForeground", "Background",
        DEF_BUTTON_ACTIVE_FG_MONO, Tk_Offset(Button, activeFg), 
        BUTTON_MASK|CHECK_BUTTON_MASK|RADIO_BUTTON_MASK
        |TK_CONFIG_MONO_ONLY},
    {TK_CONFIG_ANCHOR, "-anchor", "anchor", "Anchor",
        DEF_BUTTON_ANCHOR, Tk_Offset(Button, anchor), ALL_MASK},
    {TK_CONFIG_BORDER, "-background", "background", "Background",
        DEF_BUTTON_BG_COLOR, Tk_Offset(Button, normalBorder),
        ALL_MASK | TK_CONFIG_COLOR_ONLY},
    {TK_CONFIG_BORDER, "-background", "background", "Background",
        DEF_BUTTON_BG_MONO, Tk_Offset(Button, normalBorder),
        ALL_MASK | TK_CONFIG_MONO_ONLY},
    {TK_CONFIG_SYNONYM, "-bd", "borderWidth", (char *) NULL,
        (char *) NULL, 0, ALL_MASK},
    {TK_CONFIG_SYNONYM, "-bg", "background", (char *) NULL,
        (char *) NULL, 0, ALL_MASK},
#if defined(USE_XPM3)
    {TK_CONFIG_PIXMAP, "-bitmap", "bitmap", "Bitmap",
        DEF_BUTTON_BITMAP, Tk_Offset(Button, bitmap),
        ALL_MASK|TK_CONFIG_NULL_OK},
#else
    {TK_CONFIG_BITMAP, "-bitmap", "bitmap", "Bitmap",
        DEF_BUTTON_BITMAP, Tk_Offset(Button, bitmap),
        ALL_MASK|TK_CONFIG_NULL_OK},
#endif
    {TK_CONFIG_PIXELS, "-borderwidth", "borderWidth", "BorderWidth",
        DEF_BUTTON_BORDER_WIDTH, Tk_Offset(Button, borderWidth), ALL_MASK},
    {TK_CONFIG_STRING, "-command", "command", "Command",
        DEF_BUTTON_COMMAND, Tk_Offset(Button, command),
        BUTTON_MASK|CHECK_BUTTON_MASK|RADIO_BUTTON_MASK},
    {TK_CONFIG_ACTIVE_CURSOR, "-cursor", "cursor", "Cursor",
        DEF_BUTTON_CURSOR, Tk_Offset(Button, cursor),
        ALL_MASK|TK_CONFIG_NULL_OK},
    {TK_CONFIG_COLOR, "-disabledforeground", "disabledForeground",
        "DisabledForeground", DEF_BUTTON_DISABLED_FG_COLOR,
        Tk_Offset(Button, disabledFg), BUTTON_MASK|CHECK_BUTTON_MASK
        |RADIO_BUTTON_MASK|TK_CONFIG_COLOR_ONLY|TK_CONFIG_NULL_OK},
    {TK_CONFIG_COLOR, "-disabledforeground", "disabledForeground",
        "DisabledForeground", DEF_BUTTON_DISABLED_FG_MONO,
        Tk_Offset(Button, disabledFg), BUTTON_MASK|CHECK_BUTTON_MASK
        |RADIO_BUTTON_MASK|TK_CONFIG_MONO_ONLY|TK_CONFIG_NULL_OK},
    {TK_CONFIG_SYNONYM, "-fg", "foreground", (char *) NULL,
        (char *) NULL, 0, ALL_MASK},
    {TK_CONFIG_FONT, "-font", "font", "Font",
        DEF_BUTTON_FONT, Tk_Offset(Button, fontPtr),
        ALL_MASK},
    {TK_CONFIG_COLOR, "-foreground", "foreground", "Foreground",
        DEF_BUTTON_FG, Tk_Offset(Button, normalFg), ALL_MASK},
    {TK_CONFIG_INT, "-height", "height", "Height",
        DEF_BUTTON_HEIGHT, Tk_Offset(Button, height), ALL_MASK},
    {TK_CONFIG_STRING, "-offvalue", "offValue", "Value",
        DEF_BUTTON_OFF_VALUE, Tk_Offset(Button, offValue),
        CHECK_BUTTON_MASK},
    {TK_CONFIG_STRING, "-onvalue", "onValue", "Value",
        DEF_BUTTON_ON_VALUE, Tk_Offset(Button, onValue),
        CHECK_BUTTON_MASK},
    {TK_CONFIG_PIXELS, "-padx", "padX", "Pad",
        DEF_BUTTON_PADX, Tk_Offset(Button, padX), ALL_MASK},
    {TK_CONFIG_PIXELS, "-pady", "padY", "Pad",
        DEF_BUTTON_PADY, Tk_Offset(Button, padY), ALL_MASK},
    {TK_CONFIG_RELIEF, "-relief", "relief", "Relief",
        DEF_BUTTON_RELIEF, Tk_Offset(Button, relief), 
        BUTTON_MASK|CHECK_BUTTON_MASK|RADIO_BUTTON_MASK},
    {TK_CONFIG_RELIEF, "-relief", "relief", "Relief",
        DEF_LABEL_RELIEF, Tk_Offset(Button, relief), LABEL_MASK},
    {TK_CONFIG_COLOR, "-selector", "selector", "Foreground",
        DEF_BUTTON_SELECTOR_COLOR, Tk_Offset(Button, selectorFg),
        CHECK_BUTTON_MASK|RADIO_BUTTON_MASK|TK_CONFIG_COLOR_ONLY
        |TK_CONFIG_NULL_OK},
    {TK_CONFIG_COLOR, "-selector", "selector", "Foreground",
        DEF_BUTTON_SELECTOR_MONO, Tk_Offset(Button, selectorFg),
        CHECK_BUTTON_MASK|RADIO_BUTTON_MASK|TK_CONFIG_MONO_ONLY
        |TK_CONFIG_NULL_OK},
    {TK_CONFIG_UID, "-state", "state", "State",
        DEF_BUTTON_STATE, Tk_Offset(Button, state),
        BUTTON_MASK|CHECK_BUTTON_MASK|RADIO_BUTTON_MASK},
    {TK_CONFIG_STRING, "-text", "text", "Text",
        DEF_BUTTON_TEXT, Tk_Offset(Button, text), ALL_MASK},
    {TK_CONFIG_STRING, "-textvariable", "textVariable", "Variable",
        DEF_BUTTON_TEXT_VARIABLE, Tk_Offset(Button, textVarName),
        ALL_MASK|TK_CONFIG_NULL_OK},
    {TK_CONFIG_STRING, "-value", "value", "Value",
        DEF_BUTTON_VALUE, Tk_Offset(Button, onValue),
        RADIO_BUTTON_MASK},
    {TK_CONFIG_STRING, "-variable", "variable", "Variable",
        DEF_RADIOBUTTON_VARIABLE, Tk_Offset(Button, selVarName),
        RADIO_BUTTON_MASK},
    {TK_CONFIG_STRING, "-variable", "variable", "Variable",
        DEF_CHECKBUTTON_VARIABLE, Tk_Offset(Button, selVarName),
        CHECK_BUTTON_MASK},
    {TK_CONFIG_INT, "-width", "width", "Width",
        DEF_BUTTON_WIDTH, Tk_Offset(Button, width), ALL_MASK},
    {TK_CONFIG_END, (char *) NULL, (char *) NULL, (char *) NULL,
        (char *) NULL, 0, 0}
};

/*
 * String to print out in error messages, identifying options for
 * widget commands for different types of labels or buttons:
 */

static char *optionStrings[] = {
    "configure",
    "activate, configure, deactivate, flash, or invoke",
    "activate, configure, deactivate, deselect, flash, invoke, select, or toggle",
    "activate, configure, deactivate, deselect, flash, invoke, or select"
};

static int ButtonUpdateTime = 200; // Added by Don.

/*
 * Forward declarations for procedures defined later in this file:
 */

static void             ButtonEventProc _ANSI_ARGS_((ClientData clientData,
                            XEvent *eventPtr));
static char *           ButtonTextVarProc _ANSI_ARGS_((ClientData clientData,
                            Tcl_Interp *interp, char *name1, char *name2,
                            int flags));
static char *           ButtonVarProc _ANSI_ARGS_((ClientData clientData,
                            Tcl_Interp *interp, char *name1, char *name2,
                            int flags));
static int              ButtonWidgetCmd _ANSI_ARGS_((ClientData clientData,
                            Tcl_Interp *interp, int argc, char **argv));
static void             ComputeButtonGeometry _ANSI_ARGS_((Button *butPtr));
static int              ConfigureButton _ANSI_ARGS_((Tcl_Interp *interp,
                            Button *butPtr, int argc, char **argv,
                            int flags));
static void             DestroyButton _ANSI_ARGS_((ClientData clientData));
static void             DisplayButton _ANSI_ARGS_((ClientData clientData));
static int              InvokeButton  _ANSI_ARGS_((Button *butPtr));
\f
/*
 *--------------------------------------------------------------
 *
 * Tk_ButtonCmd --
 *
 *      This procedure is invoked to process the "button", "label",
 *      "radiobutton", and "checkbutton" Tcl commands.  See the
 *      user documentation for details on what it does.
 *
 * Results:
 *      A standard Tcl result.
 *
 * Side effects:
 *      See the user documentation.
 *
 *--------------------------------------------------------------
 */

int
Tk_ButtonCmd(clientData, interp, argc, argv)
    ClientData clientData;      /* Main window associated with
                                 * interpreter. */
    Tcl_Interp *interp;         /* Current interpreter. */
    int argc;                   /* Number of arguments. */
    char **argv;                /* Argument strings. */
{
    register Button *butPtr;
    int type;
    Tk_Window tkwin = (Tk_Window) clientData;
    Tk_Window new;

    if (argc < 2) {
        Tcl_AppendResult(interp, "wrong # args:  should be \"",
                argv[0], " pathName ?options?\"", (char *) NULL);
        return TCL_ERROR;
    }

    switch (argv[0][0]) {
        case 'l':
            type = TYPE_LABEL;
            break;
        case 'b':
            type = TYPE_BUTTON;
            break;
        case 'c':
            type = TYPE_CHECK_BUTTON;
            break;
        case 'r':
            type = TYPE_RADIO_BUTTON;
            break;
        default:
            sprintf(interp->result,
                    "unknown button-creation command \"%.50s\"");
            return TCL_ERROR;
    }

    /*
     * Create the new window.
     */

    new = Tk_CreateWindowFromPath(interp, tkwin, argv[1], (char *) NULL);
    if (new == NULL) {
        return TCL_ERROR;
    }

    /*
     * Initialize the data structure for the button.
     */

    butPtr = (Button *) ckalloc(sizeof(Button));
    butPtr->tkwin = new;
    butPtr->interp = interp;
    butPtr->type = type;
    butPtr->text = NULL;
    butPtr->textVarName = NULL;
    butPtr->bitmap = None;
    butPtr->state = tkNormalUid;
    butPtr->normalBorder = NULL;
    butPtr->activeBorder = NULL;
    butPtr->borderWidth = 0;
    butPtr->relief = TK_RELIEF_FLAT;
    butPtr->fontPtr = NULL;
    butPtr->normalFg = NULL;
    butPtr->activeFg = NULL;
    butPtr->disabledFg = NULL;
    butPtr->normalTextGC = None;
    butPtr->activeTextGC = None;
    butPtr->gray = None;
    butPtr->disabledGC = None;
    butPtr->selectorFg = NULL;
    butPtr->selectorGC = None;
    butPtr->selVarName = NULL;
    butPtr->onValue = NULL;
    butPtr->offValue = NULL;
    butPtr->cursor = None;
    butPtr->command = NULL;
    butPtr->flags = 0;
    butPtr->updateTimerToken = 0;

    Tk_SetClass(new, classNames[type]);
//fprintf(stderr, "ButtonWidgetCmd Made %s %s\n", Tk_Class(butPtr->tkwin), Tk_PathName(butPtr->tkwin));
    Tk_CreateEventHandler(butPtr->tkwin, ExposureMask|StructureNotifyMask,
            ButtonEventProc, (ClientData) butPtr);
    Tcl_CreateCommand(interp, Tk_PathName(butPtr->tkwin), ButtonWidgetCmd,
            (ClientData) butPtr, (void (*)()) NULL);
    if (ConfigureButton(interp, butPtr, argc-2, argv+2,
            configFlags[type]) != TCL_OK) {
        Tk_DestroyWindow(butPtr->tkwin);
        return TCL_ERROR;
    }

    interp->result = Tk_PathName(butPtr->tkwin);
    return TCL_OK;
}
\f
/*
 *--------------------------------------------------------------
 *
 * ButtonWidgetCmd --
 *
 *      This procedure is invoked to process the Tcl command
 *      that corresponds to a widget managed by this module.
 *      See the user documentation for details on what it does.
 *
 * Results:
 *      A standard Tcl result.
 *
 * Side effects:
 *      See the user documentation.
 *
 *--------------------------------------------------------------
 */

static int
ButtonWidgetCmd(clientData, interp, argc, argv)
    ClientData clientData;      /* Information about button widget. */
    Tcl_Interp *interp;         /* Current interpreter. */
    int argc;                   /* Number of arguments. */
    char **argv;                /* Argument strings. */
{
    register Button *butPtr = (Button *) clientData;
    int result = TCL_OK;
    int length;
    char c;

    if (argc < 2) {
        sprintf(interp->result,
                "wrong # args: should be \"%.50s option [arg arg ...]\"",
                argv[0]);
        return TCL_ERROR;
    }
    Tk_Preserve((ClientData) butPtr);
    c = argv[1][0];
    length = strlen(argv[1]);
    if ((c == 'a') && (strncmp(argv[1], "activate", length) == 0)
            && (butPtr->type != TYPE_LABEL)) {
        if (argc > 2) {
            sprintf(interp->result,
                    "wrong # args: should be \"%.50s activate\"",
                    argv[0]);
            goto error;
        }
        if (butPtr->state != tkDisabledUid) {
            butPtr->state = tkActiveUid;
            Tk_SetBackgroundFromBorder(butPtr->tkwin, butPtr->activeBorder);
            goto redisplay;
        }
    } else if ((c == 'c') && (strncmp(argv[1], "configure", length) == 0)) {
        if (argc == 2) {
            result = Tk_ConfigureInfo(interp, butPtr->tkwin, configSpecs,
                    (char *) butPtr, (char *) NULL, configFlags[butPtr->type]);
        } else if (argc == 3) {
            result = Tk_ConfigureInfo(interp, butPtr->tkwin, configSpecs,
                    (char *) butPtr, argv[2],
                    configFlags[butPtr->type]);
        } else {
            result = ConfigureButton(interp, butPtr, argc-2, argv+2,
                    configFlags[butPtr->type] | TK_CONFIG_ARGV_ONLY);
        }
    } else if ((c == 'd') && (strncmp(argv[1], "deactivate", length) == 0)
            && (length > 2) && (butPtr->type != TYPE_LABEL)) {
        if (argc > 2) {
            sprintf(interp->result,
                    "wrong # args: should be \"%.50s deactivate\"",
                    argv[0]);
            goto error;
        }
        if (butPtr->state != tkDisabledUid) {
            butPtr->state = tkNormalUid;
            Tk_SetBackgroundFromBorder(butPtr->tkwin, butPtr->normalBorder);
            goto redisplay;
        }
    } else if ((c == 'd') && (strncmp(argv[1], "deselect", length) == 0)
            && (length > 2) && (butPtr->type >= TYPE_CHECK_BUTTON)) {
        if (argc > 2) {
            sprintf(interp->result,
                    "wrong # args: should be \"%.50s deselect\"",
                    argv[0]);
            goto error;
        }
        if (butPtr->type == TYPE_CHECK_BUTTON) {
            Tcl_SetVar(interp, butPtr->selVarName, butPtr->offValue,
                    TCL_GLOBAL_ONLY);
        } else if (butPtr->flags & SELECTED) {
            Tcl_SetVar(interp, butPtr->selVarName, "", TCL_GLOBAL_ONLY);
        }
    } else if ((c == 'f') && (strncmp(argv[1], "flash", length) == 0)
        && (butPtr->type != TYPE_LABEL)) {
        int i;

        if (argc > 2) {
            sprintf(interp->result,
                    "wrong # args: should be \"%.50s flash\"",
                    argv[0]);
            goto error;
        }
        if (butPtr->state != tkDisabledUid) {
            for (i = 0; i < 4; i++) {
                butPtr->state = (butPtr->state == tkNormalUid)
                        ? tkActiveUid : tkNormalUid;
                Tk_SetBackgroundFromBorder(butPtr->tkwin,
                        (butPtr->state == tkActiveUid) ? butPtr->activeBorder
                        : butPtr->normalBorder);
                DisplayButton((ClientData) butPtr);
                XFlush(Tk_Display(butPtr->tkwin));
                Tk_Sleep(50);
            }
        }
    } else if ((c == 'i') && (strncmp(argv[1], "invoke", length) == 0)
            && (butPtr->type > TYPE_LABEL)) {
        if (argc > 2) {
            sprintf(interp->result,
                    "wrong # args: should be \"%.50s invoke\"",
                    argv[0]);
            goto error;
        }
        if (butPtr->state != tkDisabledUid) {
            result = InvokeButton(butPtr);
        }
    } else if ((c == 's') && (strncmp(argv[1], "select", length) == 0)
            && (butPtr->type >= TYPE_CHECK_BUTTON)) {
        if (argc > 2) {
            sprintf(interp->result,
                    "wrong # args: should be \"%.50s select\"",
                    argv[0]);
            goto error;
        }
        Tcl_SetVar(interp, butPtr->selVarName, butPtr->onValue, TCL_GLOBAL_ONLY);
    } else if ((c == 't') && (strncmp(argv[1], "toggle", length) == 0)
            && (length >= 2) && (butPtr->type == TYPE_CHECK_BUTTON)) {
        if (argc > 2) {
            sprintf(interp->result,
                    "wrong # args: should be \"%.50s select\"",
                    argv[0]);
            goto error;
        }
        if (butPtr->flags & SELECTED) {
            Tcl_SetVar(interp, butPtr->selVarName, butPtr->offValue, TCL_GLOBAL_ONLY);
        } else {
            Tcl_SetVar(interp, butPtr->selVarName, butPtr->onValue, TCL_GLOBAL_ONLY);
        }
    } else {
        sprintf(interp->result,
                "bad option \"%.50s\":  must be %s", argv[1],
                optionStrings[butPtr->type]);
        goto error;
    }
    Tk_Release((ClientData) butPtr);
    return result;

    redisplay:
    if (Tk_IsMapped(butPtr->tkwin) && !(butPtr->flags & REDRAW_PENDING)) {
//Tk_TimerToken last = butPtr->updateTimerToken;
        butPtr->flags |= REDRAW_PENDING;
//      Tk_DoWhenIdle(DisplayButton, (ClientData) butPtr);
        assert(butPtr->updateTimerToken == 0);
        if (butPtr->updateTimerToken == 0) {
          butPtr->updateTimerToken =
            Tk_CreateTimerHandler(
              ButtonUpdateTime,
              DisplayButton,
              (ClientData) butPtr);
        }
//fprintf(stderr, "ButtonWidgetCmd Set Timer %s %s was %d now %d\n", Tk_Class(butPtr->tkwin), Tk_PathName(butPtr->tkwin), last, butPtr->updateTimerToken);
    }
    Tk_Release((ClientData) butPtr);
    return TCL_OK;

    error:
    Tk_Release((ClientData) butPtr);
    return TCL_ERROR;
}
\f
/*
 *----------------------------------------------------------------------
 *
 * DestroyButton --
 *
 *      This procedure is invoked by Tk_EventuallyFree or Tk_Release
 *      to clean up the internal structure of a button at a safe time
 *      (when no-one is using it anymore).
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Everything associated with the widget is freed up.
 *
 *----------------------------------------------------------------------
 */

static void
DestroyButton(clientData)
    ClientData clientData;              /* Info about entry widget. */
{
    register Button *butPtr = (Button *) clientData;

    if (butPtr->text != NULL) {
        ckfree(butPtr->text);
    }
    if (butPtr->textVarName != NULL) {
        Tcl_UntraceVar(butPtr->interp, butPtr->textVarName,
                TCL_GLOBAL_ONLY|TCL_TRACE_WRITES|TCL_TRACE_UNSETS,
                ButtonTextVarProc, (ClientData) butPtr);
        ckfree(butPtr->textVarName);
    }
    if (butPtr->bitmap != None) {
#if defined(USE_XPM3)
      Tk_FreePixmap(butPtr->bitmap);
#else
      Tk_FreeBitmap(butPtr->bitmap);
#endif
    }
    if (butPtr->normalBorder != NULL) {
        Tk_Free3DBorder(butPtr->normalBorder);
    }
    if (butPtr->activeBorder != NULL) {
        Tk_Free3DBorder(butPtr->activeBorder);
    }
    if (butPtr->fontPtr != NULL) {
        Tk_FreeFontStruct(butPtr->fontPtr);
    }
    if (butPtr->normalFg != NULL) {
        Tk_FreeColor(butPtr->normalFg);
    }
    if (butPtr->disabledFg != NULL) {
        Tk_FreeColor(butPtr->disabledFg);
    }
    if (butPtr->activeFg != NULL) {
        Tk_FreeColor(butPtr->activeFg);
    }
    if (butPtr->normalTextGC != None) {
        Tk_FreeGC(butPtr->normalTextGC);
    }
    if (butPtr->activeTextGC != None) {
        Tk_FreeGC(butPtr->activeTextGC);
    }
    if (butPtr->gray != None) {
        Tk_FreeBitmap(butPtr->gray);
    }
    if (butPtr->disabledGC != None) {
        Tk_FreeGC(butPtr->disabledGC);
    }
    if (butPtr->selectorFg != NULL) {
        Tk_FreeColor(butPtr->selectorFg);
    }
    if (butPtr->selectorGC != None) {
        Tk_FreeGC(butPtr->selectorGC);
    }
    if (butPtr->selVarName != NULL) {
        Tcl_UntraceVar(butPtr->interp, butPtr->selVarName,
                TCL_GLOBAL_ONLY|TCL_TRACE_WRITES|TCL_TRACE_UNSETS,
                ButtonVarProc, (ClientData) butPtr);
        ckfree(butPtr->selVarName);
    }
    if (butPtr->onValue != NULL) {
        ckfree(butPtr->onValue);
    }
    if (butPtr->offValue != NULL) {
        ckfree(butPtr->offValue);
    }
    if (butPtr->cursor != None) {
        Tk_FreeCursor(butPtr->cursor);
    }
    if (butPtr->command != NULL) {
        ckfree(butPtr->command);
    }
    if (butPtr->updateTimerToken != NULL) {
        Tk_DeleteTimerHandler(butPtr->updateTimerToken);
//fprintf(stderr, "DestroyButton Delete Timer was %d now 0\n", butPtr->updateTimerToken);
        butPtr->updateTimerToken = 0;

    }
    ckfree((char *) butPtr);
}
\f
/*
 *----------------------------------------------------------------------
 *
 * ConfigureButton --
 *
 *      This procedure is called to process an argv/argc list, plus
 *      the Tk option database, in order to configure (or
 *      reconfigure) a button widget.
 *
 * Results:
 *      The return value is a standard Tcl result.  If TCL_ERROR is
 *      returned, then interp->result contains an error message.
 *
 * Side effects:
 *      Configuration information, such as text string, colors, font,
 *      etc. get set for butPtr;  old resources get freed, if there
 *      were any.  The button is redisplayed.
 *
 *----------------------------------------------------------------------
 */

static int
ConfigureButton(interp, butPtr, argc, argv, flags)
    Tcl_Interp *interp;         /* Used for error reporting. */
    register Button *butPtr;    /* Information about widget;  may or may
                                 * not already have values for some fields. */
    int argc;                   /* Number of valid entries in argv. */
    char **argv;                /* Arguments. */
    int flags;                  /* Flags to pass to Tk_ConfigureWidget. */
{
    XGCValues gcValues;
    GC newGC;
    unsigned long mask;

    /*
     * Eliminate any existing trace on variables monitored by the button.
     */

    if (butPtr->textVarName != NULL) {
        Tcl_UntraceVar(interp, butPtr->textVarName, 
                TCL_GLOBAL_ONLY|TCL_TRACE_WRITES|TCL_TRACE_UNSETS,
                ButtonTextVarProc, (ClientData) butPtr);
    }
    if (butPtr->selVarName != NULL) {
        Tcl_UntraceVar(interp, butPtr->selVarName, 
                TCL_GLOBAL_ONLY|TCL_TRACE_WRITES|TCL_TRACE_UNSETS,
                ButtonVarProc, (ClientData) butPtr);
    }

    if (Tk_ConfigureWidget(interp, butPtr->tkwin, configSpecs,
            argc, argv, (char *) butPtr, flags) != TCL_OK) {
        return TCL_ERROR;
    }

    /*
     * A few options need special processing, such as setting the
     * background from a 3-D border, or filling in complicated
     * defaults that couldn't be specified to Tk_ConfigureWidget.
     */

    if (butPtr->state == tkActiveUid) {
        Tk_SetBackgroundFromBorder(butPtr->tkwin, butPtr->activeBorder);
    } else {
        Tk_SetBackgroundFromBorder(butPtr->tkwin, butPtr->normalBorder);
        if ((butPtr->state != tkNormalUid)
                && (butPtr->state != tkDisabledUid)) {
            Tcl_AppendResult(interp, "bad state value \"", butPtr->state,
                    "\":  must be normal, active, or disabled", (char *) NULL);
            butPtr->state = tkNormalUid;
            return TCL_ERROR;
        }
    }

    gcValues.font = butPtr->fontPtr->fid;
    gcValues.foreground = butPtr->normalFg->pixel;
    gcValues.background = Tk_3DBorderColor(butPtr->normalBorder)->pixel;

    /*
     * Note: GraphicsExpose events are disabled in normalTextGC because it's
     * used to copy stuff from an off-screen pixmap onto the screen (we know
     * that there's no problem with obscured areas).
     */

    gcValues.graphics_exposures = False;
    newGC = Tk_GetGC(butPtr->tkwin,
            GCForeground|GCBackground|GCFont|GCGraphicsExposures, &gcValues);
    if (butPtr->normalTextGC != None) {
        Tk_FreeGC(butPtr->normalTextGC);
    }
    butPtr->normalTextGC = newGC;

    if (butPtr->activeFg != NULL) {
        gcValues.font = butPtr->fontPtr->fid;
        gcValues.foreground = butPtr->activeFg->pixel;
        gcValues.background = Tk_3DBorderColor(butPtr->activeBorder)->pixel;
        newGC = Tk_GetGC(butPtr->tkwin, GCForeground|GCBackground|GCFont,
                &gcValues);
        if (butPtr->activeTextGC != None) {
            Tk_FreeGC(butPtr->activeTextGC);
        }
        butPtr->activeTextGC = newGC;
    }

    gcValues.font = butPtr->fontPtr->fid;
    gcValues.background = Tk_3DBorderColor(butPtr->normalBorder)->pixel;
    if (butPtr->disabledFg != NULL) {
        gcValues.foreground = butPtr->disabledFg->pixel;
        mask = GCForeground|GCBackground|GCFont;
    } else {
        gcValues.foreground = gcValues.background;
        if (butPtr->gray == None) {
            butPtr->gray = Tk_GetBitmap(interp, butPtr->tkwin,
                    Tk_GetUid("gray50"));
            if (butPtr->gray == None) {
                return TCL_ERROR;
            }
        }
        gcValues.fill_style = FillStippled;
        gcValues.stipple = butPtr->gray;
        mask = GCForeground|GCFillStyle|GCStipple;
    }
    newGC = Tk_GetGC(butPtr->tkwin, mask, &gcValues);
    if (butPtr->disabledGC != None) {
        Tk_FreeGC(butPtr->disabledGC);
    }
    butPtr->disabledGC = newGC;

    if (butPtr->padX < 0) {
        butPtr->padX = 0;
    }
    if (butPtr->padY < 0) {
        butPtr->padY = 0;
    }

    if (butPtr->type >= TYPE_CHECK_BUTTON) {
        char *value;

        if (butPtr->selectorFg != NULL) {
            gcValues.foreground = butPtr->selectorFg->pixel;
            newGC = Tk_GetGC(butPtr->tkwin, GCForeground, &gcValues);
        } else {
            newGC = None;
        }
        if (butPtr->selectorGC != None) {
            Tk_FreeGC(butPtr->selectorGC);
        }
        butPtr->selectorGC = newGC;

        if (butPtr->selVarName == NULL) {
            butPtr->selVarName = (char *) ckalloc((unsigned)
                    (strlen(Tk_Name(butPtr->tkwin)) + 1));
            strcpy(butPtr->selVarName, Tk_Name(butPtr->tkwin));
        }
        if (butPtr->onValue == NULL) {
            butPtr->onValue = (char *) ckalloc((unsigned)
                    (strlen(Tk_Name(butPtr->tkwin)) + 1));
            strcpy(butPtr->onValue, Tk_Name(butPtr->tkwin));
        }

        /*
         * Select the button if the associated variable has the
         * appropriate value, initialize the variable if it doesn't
         * exist, then set a trace on the variable to monitor future
         * changes to its value.
         */

        value = Tcl_GetVar(interp, butPtr->selVarName, TCL_GLOBAL_ONLY);
        butPtr->flags &= ~SELECTED;
        if (value != NULL) {
            if (strcmp(value, butPtr->onValue) == 0) {
                butPtr->flags |= SELECTED;
            }
        } else {
            Tcl_SetVar(interp, butPtr->selVarName,
                    (butPtr->type == TYPE_CHECK_BUTTON) ? butPtr->offValue : "",
                    TCL_GLOBAL_ONLY);
        }
        Tcl_TraceVar(interp, butPtr->selVarName,
                TCL_GLOBAL_ONLY|TCL_TRACE_WRITES|TCL_TRACE_UNSETS,
                ButtonVarProc, (ClientData) butPtr);
    }

    /*
     * If the button is to display the value of a variable, then set up
     * a trace on the variable's value, create the variable if it doesn't
     * exist, and fetch its current value.
     */

    if ((butPtr->bitmap == None) && (butPtr->textVarName != NULL)) {
        char *value;

        value = Tcl_GetVar(interp, butPtr->textVarName, TCL_GLOBAL_ONLY);
        if (value == NULL) {
            Tcl_SetVar(interp, butPtr->textVarName, butPtr->text,
                    TCL_GLOBAL_ONLY);
        } else {
            if (butPtr->text != NULL) {
                ckfree(butPtr->text);
            }
            butPtr->text = ckalloc((unsigned) (strlen(value) + 1));
            strcpy(butPtr->text, value);
        }
        Tcl_TraceVar(interp, butPtr->textVarName,
                TCL_GLOBAL_ONLY|TCL_TRACE_WRITES|TCL_TRACE_UNSETS,
                ButtonTextVarProc, (ClientData) butPtr);
    }

    ComputeButtonGeometry(butPtr);

    /*
     * Lastly, arrange for the button to be redisplayed.
     */

    if (Tk_IsMapped(butPtr->tkwin) && !(butPtr->flags & REDRAW_PENDING)) {
//Tk_TimerToken last = butPtr->updateTimerToken;
        butPtr->flags |= REDRAW_PENDING;
//      Tk_DoWhenIdle(DisplayButton, (ClientData) butPtr);
        assert(butPtr->updateTimerToken == 0);
        if (butPtr->updateTimerToken == 0) {
          butPtr->updateTimerToken =
            Tk_CreateTimerHandler(
              ButtonUpdateTime,
              DisplayButton,
              (ClientData) butPtr);
        }
//fprintf(stderr, "ConfigureButton Set Timer %s %s was %d now %d\n", Tk_Class(butPtr->tkwin), Tk_PathName(butPtr->tkwin), last, butPtr->updateTimerToken);
    }

    return TCL_OK;
}
\f
/*
 *----------------------------------------------------------------------
 *
 * DisplayButton --
 *
 *      This procedure is invoked to display a button widget.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Commands are output to X to display the button in its
 *      current mode.
 *
 *----------------------------------------------------------------------
 */

static void
DisplayButton(clientData)
    ClientData clientData;      /* Information about widget. */
{
    register Button *butPtr = (Button *) clientData;
    GC gc;
    Tk_3DBorder border;
    Pixmap pixmap;
    int x = 0;                  /* Initialization only needed to stop
                                 * compiler warning. */
    int y;
    register Tk_Window tkwin = butPtr->tkwin;

//fprintf(stderr, "DisplayButton Handled Timer %s %s was %d now 0\n", Tk_Class(butPtr->tkwin), Tk_PathName(butPtr->tkwin), butPtr->updateTimerToken);

    assert(butPtr->updateTimerToken != 0);
    butPtr->updateTimerToken = 0;

    butPtr->flags &= ~REDRAW_PENDING;
    if ((butPtr->tkwin == NULL) || !Tk_IsMapped(tkwin)) {
        return;
    }

    if ((butPtr->state == tkDisabledUid) && (butPtr->disabledFg != NULL)) {
        gc = butPtr->disabledGC;
        border = butPtr->normalBorder;
    } else if (butPtr->state == tkActiveUid) {
        gc = butPtr->activeTextGC;
        border = butPtr->activeBorder;
    } else {
        gc = butPtr->normalTextGC;
        border = butPtr->normalBorder;
    }

    /*
     * In order to avoid screen flashes, this procedure redraws
     * the button in a pixmap, then copies the pixmap to the
     * screen in a single operation.  This means that there's no
     * point in time where the on-sreen image has been cleared.
     */

    pixmap = XCreatePixmap(Tk_Display(tkwin), Tk_WindowId(tkwin),
            Tk_Width(tkwin), Tk_Height(tkwin),
            Tk_DefaultDepth(Tk_Screen(tkwin)));
    Tk_Fill3DRectangle(Tk_Display(tkwin), pixmap, border,
            0, 0, Tk_Width(tkwin), Tk_Height(tkwin), 0, TK_RELIEF_FLAT);

    /*
     * Display bitmap or text for button.
     */

    if (butPtr->bitmap != None) {
        unsigned int width, height;

#if defined(USE_XPM3)
        Tk_SizeOfPixmap(butPtr->bitmap, &width, &height);
#else
        Tk_SizeOfBitmap(butPtr->bitmap, &width, &height);
#endif
        switch (butPtr->anchor) {
            case TK_ANCHOR_NW: case TK_ANCHOR_W: case TK_ANCHOR_SW:
                x = butPtr->borderWidth + butPtr->selectorSpace
                        + butPtr->padX + 1;
                break;
            case TK_ANCHOR_N: case TK_ANCHOR_CENTER: case TK_ANCHOR_S:
                x = (Tk_Width(tkwin) + butPtr->selectorSpace - width)/2;
                break;
            default:
                x = Tk_Width(tkwin) - butPtr->borderWidth - butPtr->padX
                        - width - 1;
                break;
        }
        switch (butPtr->anchor) {
            case TK_ANCHOR_NW: case TK_ANCHOR_N: case TK_ANCHOR_NE:
                y = butPtr->borderWidth + butPtr->padY + 1;
                break;
            case TK_ANCHOR_W: case TK_ANCHOR_CENTER: case TK_ANCHOR_E:
                y = (Tk_Height(tkwin) - height)/2;
                break;
            default:
                y = Tk_Height(tkwin) - butPtr->borderWidth - butPtr->padY
                        - height - 1;
                break;
        }
        if (butPtr->relief == TK_RELIEF_RAISED) {
            x -= 1;
            y -= 1;
        } else if (butPtr->relief == TK_RELIEF_SUNKEN) {
            x += 1;
            y += 1;
        }
#if defined(USE_XPM3)        
        XCopyArea(Tk_Display(tkwin), butPtr->bitmap, pixmap,
                gc, 0, 0, width, height, x, y);
#else
        XCopyPlane(Tk_Display(tkwin), butPtr->bitmap, pixmap,
                gc, 0, 0, width, height, x, y, 1);
#endif
        y += height/2;
    } else {
        switch (butPtr->anchor) {
            case TK_ANCHOR_NW: case TK_ANCHOR_W: case TK_ANCHOR_SW:
                x = butPtr->borderWidth + butPtr->padX + butPtr->selectorSpace
                        + butPtr->leftBearing + 1;
                break;
            case TK_ANCHOR_N: case TK_ANCHOR_CENTER: case TK_ANCHOR_S:
                x = (Tk_Width(tkwin) + butPtr->selectorSpace
                        + butPtr->leftBearing - butPtr->rightBearing)/2;
                break;
            default:
                x = Tk_Width(tkwin) - butPtr->borderWidth - butPtr->padX
                        - butPtr->rightBearing - 1;
                break;
        }
        switch (butPtr->anchor) {
            case TK_ANCHOR_NW: case TK_ANCHOR_N: case TK_ANCHOR_NE:
                y = butPtr->borderWidth + butPtr->fontPtr->ascent
                        + butPtr->padY + 1;
                break;
            case TK_ANCHOR_W: case TK_ANCHOR_CENTER: case TK_ANCHOR_E:
                y = (Tk_Height(tkwin) + butPtr->fontPtr->ascent
                        - butPtr->fontPtr->descent)/2;
                break;
            default:
                y = Tk_Height(tkwin) - butPtr->borderWidth - butPtr->padY
                        - butPtr->fontPtr->descent - 1;
                break;
        }
        if (butPtr->relief == TK_RELIEF_RAISED) {
            x -= 1;
            y -= 1;
        } else if (butPtr->relief == TK_RELIEF_SUNKEN) {
            x += 1;
            y += 1;
        }
        XDrawString(Tk_Display(tkwin), pixmap, gc, x, y,
                butPtr->text, butPtr->textLength);
        y -= (butPtr->fontPtr->ascent - butPtr->fontPtr->descent)/2;
        x -= butPtr->leftBearing;
    }

    /*
     * Draw the selector for check buttons and radio buttons.  At this
     * point x and y refer to the top-left corner of the text or bitmap.
     */

    if ((butPtr->type == TYPE_CHECK_BUTTON) && (butPtr->selectorGC != None)) {
        int dim;

        dim = butPtr->selectorDiameter;
        x -= (butPtr->selectorSpace + butPtr->padX + dim)/2;
        y -= dim/2;
        Tk_Draw3DRectangle(Tk_Display(tkwin), pixmap, border, x, y,
                dim, dim, butPtr->borderWidth, TK_RELIEF_SUNKEN);
        x += butPtr->borderWidth;
        y += butPtr->borderWidth;
        dim -= 2*butPtr->borderWidth;
        if (dim > 0) {
            if (butPtr->flags & SELECTED) {
                XFillRectangle(Tk_Display(tkwin), pixmap, butPtr->selectorGC,
                        x, y, (unsigned int) dim, (unsigned int) dim);
            } else {
                Tk_Fill3DRectangle(Tk_Display(tkwin), pixmap,
                        butPtr->normalBorder, x, y, dim, dim,
                        butPtr->borderWidth, TK_RELIEF_FLAT);
            }
        }
    } else if ((butPtr->type == TYPE_RADIO_BUTTON)
            && (butPtr->selectorGC != None)) {
        XPoint points[4];
        int radius;

        radius = butPtr->selectorDiameter/2;
        points[0].x = x - (butPtr->selectorSpace + butPtr->padX
                + butPtr->selectorDiameter)/2;
        points[0].y = y;
        points[1].x = points[0].x + radius;
        points[1].y = points[0].y + radius;
        points[2].x = points[1].x + radius;
        points[2].y = points[0].y;
        points[3].x = points[1].x;
        points[3].y = points[0].y - radius;
        if (butPtr->flags & SELECTED) {
            XFillPolygon(Tk_Display(tkwin), pixmap, butPtr->selectorGC,
                    points, 4, Convex, CoordModeOrigin);
        } else {
            Tk_Fill3DPolygon(Tk_Display(tkwin), pixmap, butPtr->normalBorder,
                    points, 4, butPtr->borderWidth, TK_RELIEF_FLAT);
        }
        Tk_Draw3DPolygon(Tk_Display(tkwin), pixmap, border,
                points, 4, butPtr->borderWidth, TK_RELIEF_RAISED);
    }

    /*
     * If the button is disabled with a stipple rather than a special
     * foreground color, generate the stippled effect.
     */

    if ((butPtr->state == tkDisabledUid) && (butPtr->disabledFg == NULL)) {
        XFillRectangle(Tk_Display(tkwin), pixmap, butPtr->disabledGC,
                butPtr->borderWidth, butPtr->borderWidth,
                (unsigned) (Tk_Width(tkwin) - 2*butPtr->borderWidth),
                (unsigned) (Tk_Height(tkwin) - 2*butPtr->borderWidth));
    }

    /*
     * Draw the border last.  This way, if the button's contents
     * overflow onto the border they'll be covered up by the border.
     */

    if (butPtr->relief != TK_RELIEF_FLAT) {
        Tk_Draw3DRectangle(Tk_Display(tkwin), pixmap, border,0, 0,
                Tk_Width(tkwin), Tk_Height(tkwin), butPtr->borderWidth,
                butPtr->relief);
    }

    /*
     * Copy the information from the off-screen pixmap onto the screen,
     * then delete the pixmap.
     */

    XCopyArea(Tk_Display(tkwin), pixmap, Tk_WindowId(tkwin),
        butPtr->normalTextGC, 0, 0, Tk_Width(tkwin), Tk_Height(tkwin), 0, 0);
    XFreePixmap(Tk_Display(tkwin), pixmap);
}
\f
/*
 *--------------------------------------------------------------
 *
 * ButtonEventProc --
 *
 *      This procedure is invoked by the Tk dispatcher for various
 *      events on buttons.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      When the window gets deleted, internal structures get
 *      cleaned up.  When it gets exposed, it is redisplayed.
 *
 *--------------------------------------------------------------
 */

static void
ButtonEventProc(clientData, eventPtr)
    ClientData clientData;      /* Information about window. */
    XEvent *eventPtr;           /* Information about event. */
{
    Button *butPtr = (Button *) clientData;
    if ((eventPtr->type == Expose) && (eventPtr->xexpose.count == 0)) {
        if ((butPtr->tkwin != NULL) && !(butPtr->flags & REDRAW_PENDING)) {
//Tk_TimerToken last = butPtr->updateTimerToken;
            butPtr->flags |= REDRAW_PENDING;
//          Tk_DoWhenIdle(DisplayButton, (ClientData) butPtr);
            assert(butPtr->updateTimerToken == NULL);
            if (butPtr->updateTimerToken == NULL) {
              butPtr->updateTimerToken =
                Tk_CreateTimerHandler(
                  ButtonUpdateTime,
                  DisplayButton,
                  (ClientData) butPtr);
            } // if
//fprintf(stderr, "ButtonEventProc Expose Set Timer %s %s was %d now %d\n", Tk_Class(butPtr->tkwin), Tk_PathName(butPtr->tkwin), last, butPtr->updateTimerToken);
        }
    } else if (eventPtr->type == DestroyNotify) {
        Tcl_DeleteCommand(butPtr->interp, Tk_PathName(butPtr->tkwin));
        butPtr->tkwin = NULL;
        if (butPtr->flags & REDRAW_PENDING) {
//fprintf(stderr, "ButtonEventProc Destroy Timer was %d now 0\n", butPtr->updateTimerToken);
//          Tk_CancelIdleCall(DisplayButton, (ClientData) butPtr);
            butPtr->flags &= ~REDRAW_PENDING;
            assert(butPtr->updateTimerToken != NULL);
            if (butPtr->updateTimerToken != NULL) {
                Tk_DeleteTimerHandler(butPtr->updateTimerToken);
                butPtr->updateTimerToken = 0;
            }
        }
        Tk_EventuallyFree((ClientData) butPtr, DestroyButton);
    }
}
\f
/*
 *----------------------------------------------------------------------
 *
 * ComputeButtonGeometry --
 *
 *      After changes in a button's text or bitmap, this procedure
 *      recomputes the button's geometry and passes this information
 *      along to the geometry manager for the window.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The button's window may change size.
 *
 *----------------------------------------------------------------------
 */

static void
ComputeButtonGeometry(butPtr)
    register Button *butPtr;    /* Button whose geometry may have changed. */
{
    XCharStruct bbox;
    int dummy;
    unsigned int width, height;

    butPtr->selectorSpace = 0;
    if (butPtr->bitmap != None) {
#if defined(USE_XPM3)
        Tk_SizeOfPixmap(butPtr->bitmap, &width, &height);
#else
        Tk_SizeOfBitmap(butPtr->bitmap, &width, &height);
#endif
        if (butPtr->width > 0) {
            width = butPtr->width;
        }
        if (butPtr->height > 0) {
            height = butPtr->height;
        }
        if ((butPtr->type >= TYPE_CHECK_BUTTON)
                && (butPtr->selectorGC != None)) {
            butPtr->selectorSpace = (14*height)/10;
            if (butPtr->type == TYPE_CHECK_BUTTON) {
                butPtr->selectorDiameter = (65*height)/100;
            } else {
                butPtr->selectorDiameter = (75*height)/100;
            }
        }
    } else {
        butPtr->textLength = strlen(butPtr->text);
        XTextExtents(butPtr->fontPtr, butPtr->text, butPtr->textLength,
                &dummy, &dummy, &dummy, &bbox);
        butPtr->leftBearing = bbox.lbearing;
        butPtr->rightBearing = bbox.rbearing;
        width = bbox.lbearing + bbox.rbearing;
        height = butPtr->fontPtr->ascent + butPtr->fontPtr->descent;
        if (butPtr->width > 0) {
            width = butPtr->width * XTextWidth(butPtr->fontPtr, "0", 1);
        }
        if (butPtr->height > 0) {
            height *= butPtr->height;
        }
        if ((butPtr->type >= TYPE_CHECK_BUTTON)
                && (butPtr->selectorGC != None)) {
            butPtr->selectorDiameter = butPtr->fontPtr->ascent
                    + butPtr->fontPtr->descent;
            if (butPtr->type == TYPE_CHECK_BUTTON) {
                butPtr->selectorDiameter = (80*butPtr->selectorDiameter)/100;
            }
            butPtr->selectorSpace = butPtr->selectorDiameter + butPtr->padX;
        }
    }

    /*
     * When issuing the geometry request, add extra space for the selector,
     * if any, and for the border and padding, plus two extra pixels so the
     * display can be offset by 1 pixel in either direction for the raised
     * or lowered effect.
     */

    width += 2*butPtr->padX;
    height += 2*butPtr->padY;
    Tk_GeometryRequest(butPtr->tkwin, (int) (width + butPtr->selectorSpace
            + 2*butPtr->borderWidth + 2),
            (int) (height + 2*butPtr->borderWidth + 2));
    Tk_SetInternalBorder(butPtr->tkwin, butPtr->borderWidth);
}
\f
/*
 *----------------------------------------------------------------------
 *
 * InvokeButton --
 *
 *      This procedure is called to carry out the actions associated
 *      with a button, such as invoking a Tcl command or setting a
 *      variable.  This procedure is invoked, for example, when the
 *      button is invoked via the mouse.
 *
 * Results:
 *      A standard Tcl return value.  Information is also left in
 *      interp->result.
 *
 * Side effects:
 *      Depends on the button and its associated command.
 *
 *----------------------------------------------------------------------
 */

static int
InvokeButton(butPtr)
    register Button *butPtr;            /* Information about button. */
{
    if (butPtr->type == TYPE_CHECK_BUTTON) {
        if (butPtr->flags & SELECTED) {
            Tcl_SetVar(butPtr->interp, butPtr->selVarName, butPtr->offValue,
                    TCL_GLOBAL_ONLY);
        } else {
            Tcl_SetVar(butPtr->interp, butPtr->selVarName, butPtr->onValue,
                    TCL_GLOBAL_ONLY);
        }
    } else if (butPtr->type == TYPE_RADIO_BUTTON) {
        Tcl_SetVar(butPtr->interp, butPtr->selVarName, butPtr->onValue,
                TCL_GLOBAL_ONLY);
    }
    if ((butPtr->type != TYPE_LABEL) && (butPtr->command != NULL)) {
        return Tcl_GlobalEval(butPtr->interp, butPtr->command);
    }
    return TCL_OK;
}
\f
/*
 *--------------------------------------------------------------
 *
 * ButtonVarProc --
 *
 *      This procedure is invoked when someone changes the
 *      state variable associated with a radio button.  Depending
 *      on the new value of the button's variable, the button
 *      may be selected or deselected.
 *
 * Results:
 *      NULL is always returned.
 *
 * Side effects:
 *      The button may become selected or deselected.
 *
 *--------------------------------------------------------------
 */

        /* ARGSUSED */
static char *
ButtonVarProc(clientData, interp, name1, name2, flags)
    ClientData clientData;      /* Information about button. */
    Tcl_Interp *interp;         /* Interpreter containing variable. */
    char *name1;                /* Name of variable. */
    char *name2;                /* Second part of variable name. */
    int flags;                  /* Information about what happened. */
{
    register Button *butPtr = (Button *) clientData;
    char *value;

    /*
     * If the variable is being unset, then just re-establish the
     * trace unless the whole interpreter is going away.
     */

    if (flags & TCL_TRACE_UNSETS) {
        butPtr->flags &= ~SELECTED;
        if ((flags & TCL_TRACE_DESTROYED) && !(flags & TCL_INTERP_DESTROYED)) {
            Tcl_TraceVar2(interp, name1, name2,
                    TCL_GLOBAL_ONLY|TCL_TRACE_WRITES|TCL_TRACE_UNSETS,
                    ButtonVarProc, clientData);
        }
        goto redisplay;
    }

    /*
     * Use the value of the variable to update the selected status of
     * the button.
     */

    value = Tcl_GetVar2(interp, name1, name2, flags & TCL_GLOBAL_ONLY);
    if (strcmp(value, butPtr->onValue) == 0) {
        if (butPtr->flags & SELECTED) {
            return (char *) NULL;
        }
        butPtr->flags |= SELECTED;
    } else if (butPtr->flags & SELECTED) {
        butPtr->flags &= ~SELECTED;
    } else {
        return (char *) NULL;
    }

    redisplay:
    if ((butPtr->tkwin != NULL) && Tk_IsMapped(butPtr->tkwin)
            && !(butPtr->flags & REDRAW_PENDING)) {
//Tk_TimerToken last = butPtr->updateTimerToken;
        butPtr->flags |= REDRAW_PENDING;
//      Tk_DoWhenIdle(DisplayButton, (ClientData) butPtr);
        assert(butPtr->updateTimerToken == NULL);
        if (butPtr->updateTimerToken == NULL) {
            butPtr->updateTimerToken =
              Tk_CreateTimerHandler(
                ButtonUpdateTime,
                DisplayButton,
                (ClientData) butPtr);
        }
//fprintf(stderr, "ButtonVarProc Set Timer %s %s was %d now %d\n", Tk_Class(butPtr->tkwin), Tk_PathName(butPtr->tkwin), last, butPtr->updateTimerToken);
    }
    return (char *) NULL;
}
\f
/*
 *--------------------------------------------------------------
 *
 * ButtonTextVarProc --
 *
 *      This procedure is invoked when someone changes the variable
 *      whose contents are to be displayed in a button.
 *
 * Results:
 *      NULL is always returned.
 *
 * Side effects:
 *      The text displayed in the button will change to match the
 *      variable.
 *
 *--------------------------------------------------------------
 */

        /* ARGSUSED */
static char *
ButtonTextVarProc(clientData, interp, name1, name2, flags)
    ClientData clientData;      /* Information about button. */
    Tcl_Interp *interp;         /* Interpreter containing variable. */
    char *name1;                /* Name of variable. */
    char *name2;                /* Second part of variable name. */
    int flags;                  /* Information about what happened. */
{
    register Button *butPtr = (Button *) clientData;
    char *value;

    /*
     * If the variable is unset, then immediately recreate it unless
     * the whole interpreter is going away.
     */

    if (flags & TCL_TRACE_UNSETS) {
        if ((flags & TCL_TRACE_DESTROYED) && !(flags & TCL_INTERP_DESTROYED)) {
            Tcl_SetVar2(interp, name1, name2, butPtr->text,
                    flags & TCL_GLOBAL_ONLY);
            Tcl_TraceVar2(interp, name1, name2,
                    TCL_GLOBAL_ONLY|TCL_TRACE_WRITES|TCL_TRACE_UNSETS,
                    ButtonTextVarProc, clientData);
        }
        return (char *) NULL;
    }

    value = Tcl_GetVar2(interp, name1, name2, flags & TCL_GLOBAL_ONLY);
    if (value == NULL) {
        value = "";
    }
    if (butPtr->text != NULL) {
        ckfree(butPtr->text);
    }
    butPtr->text = ckalloc((unsigned) (strlen(value) + 1));
    strcpy(butPtr->text, value);
    ComputeButtonGeometry(butPtr);

    if ((butPtr->tkwin != NULL) && Tk_IsMapped(butPtr->tkwin)
            && !(butPtr->flags & REDRAW_PENDING)) {
//Tk_TimerToken last = butPtr->updateTimerToken;
        butPtr->flags |= REDRAW_PENDING;
//      Tk_DoWhenIdle(DisplayButton, (ClientData) butPtr);
        assert(butPtr->updateTimerToken == NULL);
        if (butPtr->updateTimerToken == NULL) {
            butPtr->updateTimerToken =
              Tk_CreateTimerHandler(
                ButtonUpdateTime,
                DisplayButton,
                (ClientData) butPtr);
        }
//fprintf(stderr, "ButtonTextVarProc Set Timer %s %s was %d now %d\n", Tk_Class(butPtr->tkwin), Tk_PathName(butPtr->tkwin), last, butPtr->updateTimerToken);
    }
    return (char *) NULL;
}