implement small-screen support for the initial micropolis screen

[micropolis] / src / tk / tkwindow.c

/* 
 * tkWindow.c --
 *
 *      This file provides basic window-manipulation procedures,
 *      which are equivalent to procedures in Xlib (and even
 *      invoke them) but also maintain the local Tk_Window
 *      structure.
 *
 * Copyright 1989-1992 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/tkWindow.c,v 1.92 92/08/21 11:42:44 ouster Exp $ SPRITE (Berkeley)";
#endif

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

/*
 * Global absolute file name:
 */
char *TK_Library = TK_LIBRARY;

/*
 * Count of open displays.
 */
int tk_Displays;

/*
 * Count of number of main windows currently open in this process.
 */

int tk_NumMainWindows;

/*
 * Added by dhopkins for OLPC Micropolis gtk.Socket integration. 
 */

Window tk_RootWindow = 0;

/*
 * List of all displays currently in use.
 */

TkDisplay *tkDisplayList = NULL;

/*
 * Have statics in this module been initialized?
 */

static initialized = 0;

/*
 * Context information used to map from X window id's to
 * TkWindow structures (during event handling, for example):
 */

XContext tkWindowContext;

/*
 * The variables below hold several uid's that are used in many places
 * in the toolkit.
 */

Tk_Uid tkDisabledUid = NULL;
Tk_Uid tkActiveUid = NULL;
Tk_Uid tkNormalUid = NULL;

/*
 * Default values for "changes" and "atts" fields of TkWindows.  Note
 * that Tk always requests all events for all windows, except StructureNotify
 * events on internal windows:  these events are generated internally.
 */

static XWindowChanges defChanges = {
    0, 0, 1, 1, 0, 0, Above
};
#define ALL_EVENTS_MASK \
    KeyPressMask|KeyReleaseMask|ButtonPressMask|ButtonReleaseMask| \
    EnterWindowMask|LeaveWindowMask|PointerMotionMask|ExposureMask| \
    VisibilityChangeMask|SubstructureNotifyMask| \
    FocusChangeMask|PropertyChangeMask|ColormapChangeMask
static XSetWindowAttributes defAtts= {
    None,                       /* background_pixmap */
    0,                          /* background_pixel */
    CopyFromParent,             /* border_pixmap */
    0,                          /* border_pixel */
    ForgetGravity,              /* bit_gravity */
    NorthWestGravity,           /* win_gravity */
    NotUseful,                  /* backing_store */
    ~0,                         /* backing_planes */
    0,                          /* backing_pixel */
    False,                      /* save_under */
    ALL_EVENTS_MASK,            /* event_mask */
    0,                          /* do_not_propagate_mask */
    False,                      /* override_redirect */
    CopyFromParent,             /* colormap */
    None                        /* cursor */
};

/*
 * The following structure defines all of the commands supported by
 * Tk, and the C procedures that execute them.
 */

typedef struct {
    char *name;                 /* Name of command. */
    int (*cmdProc) _ANSI_ARGS_((ClientData clientData, Tcl_Interp *interp,
            int argc, char **argv));
                                /* Command procedure. */
} TkCmd;

TkCmd commands[] = {
    /*
     * Commands that are part of the intrinsics:
     */

    {"after",           Tk_AfterCmd},
    {"bind",            Tk_BindCmd},
    {"destroy",         Tk_DestroyCmd},
    {"focus",           Tk_FocusCmd},
    {"grab",            Tk_GrabCmd},
    {"option",          Tk_OptionCmd},
    {"pack",            Tk_PackCmd},
    {"place",           Tk_PlaceCmd},
    {"selection",       Tk_SelectionCmd},
    {"tkwait",          Tk_TkwaitCmd},
    {"update",          Tk_UpdateCmd},
    {"winfo",           Tk_WinfoCmd},
    {"wm",              Tk_WmCmd},
    {"accept",          Tcp_AcceptCmd},
    {"shutdown",        Tcp_ShutdownCmd},
    {"connect",         Tcp_ConnectCmd},
    {"filehandler",     Tcp_FileHandlerCmd},

    /*
     * Widget-creation commands.
     */
    {"button",          Tk_ButtonCmd},
    {"canvas",          Tk_CanvasCmd},
    {"checkbutton",     Tk_ButtonCmd},
    {"entry",           Tk_EntryCmd},
    {"frame",           Tk_FrameCmd},
    {"label",           Tk_ButtonCmd},
    {"listbox",         Tk_ListboxCmd},
    {"menu",            Tk_MenuCmd},
    {"menubutton",      Tk_MenubuttonCmd},
    {"message",         Tk_MessageCmd},
    {"radiobutton",     Tk_ButtonCmd},
    {"scale",           Tk_ScaleCmd},
    {"scrollbar",       Tk_ScrollbarCmd},
    {"text",            Tk_TextCmd},
    {"toplevel",        Tk_FrameCmd},
    {(char *) NULL,     (int (*)()) NULL}
};

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

static Tk_Window        CreateTopLevelWindow _ANSI_ARGS_((Tcl_Interp *interp,
                            Tk_Window parent, char *name, char *screenName));
static void             DoConfigureNotify _ANSI_ARGS_((TkWindow *winPtr));
static TkDisplay *      GetScreen _ANSI_ARGS_((Tcl_Interp *interp,
                            char *screenName, int *screenPtr));
static int              NameWindow _ANSI_ARGS_((Tcl_Interp *interp,
                            TkWindow *winPtr, TkWindow *parentPtr,
                            char *name));
static TkWindow *       NewWindow _ANSI_ARGS_((TkDisplay *dispPtr,
                            int screenNum));
\f
/*
 *----------------------------------------------------------------------
 *
 * CreateTopLevelWindow --
 *
 *      Make a new window that will be at top-level (its parent will
 *      be the root window of a screen).
 *
 * Results:
 *      The return value is a token for the new window, or NULL if
 *      an error prevented the new window from being created.  If
 *      NULL is returned, an error message will be left in
 *      interp->result.
 *
 * Side effects:
 *      A new window structure is allocated locally.  An X
 *      window is NOT initially created, but will be created
 *      the first time the window is mapped.
 *
 *----------------------------------------------------------------------
 */

static Tk_Window
CreateTopLevelWindow(interp, parent, name, screenName)
    Tcl_Interp *interp;         /* Interpreter to use for error reporting. */
    Tk_Window parent;           /* Token for logical parent of new window
                                 * (used for naming, options, etc.).  May
                                 * be NULL. */
    char *name;                 /* Name for new window;  if parent is
                                 * non-NULL, must be unique among parent's
                                 * children. */
    char *screenName;           /* Name of screen on which to create
                                 * window.  NULL means use DISPLAY environment
                                 * variable to determine.  Empty string means
                                 * use parent's screen, or DISPLAY if no
                                 * parent. */
{
    register TkWindow *winPtr;
    register TkDisplay *dispPtr;
    int screenId;

    if (!initialized) {
        initialized = 1;
        tkWindowContext = XUniqueContext();
        tkActiveUid = Tk_GetUid("active");
        tkDisabledUid = Tk_GetUid("disabled");
        tkNormalUid = Tk_GetUid("normal");
    }

    if ((parent != NULL) && (screenName != NULL) && (screenName[0] == '\0')) {
        dispPtr = ((TkWindow *) parent)->dispPtr;
        screenId = Tk_ScreenNumber(parent);
    } else {
        dispPtr = GetScreen(interp, screenName, &screenId);
        if (dispPtr == NULL) {
            return (Tk_Window) NULL;
        }
    }

    winPtr = NewWindow(dispPtr, screenId);

    /*
     * Internal windows don't normally ask for StructureNotify events,
     * since we can generate them internally.  However, for top-level
     * windows we need to as for the events because the window could
     * be manipulated externally.
     */

    winPtr->atts.event_mask |= StructureNotifyMask;

    /*
     * (Need to set the TK_TOP_LEVEL flag immediately here;  otherwise
     * Tk_DestroyWindow will core dump if it is called before the flag
     * has been set.)
     */

    winPtr->flags |= TK_TOP_LEVEL;
    if (parent != NULL) {
        if (NameWindow(interp, winPtr, (TkWindow *) parent, name) != TCL_OK) {
            Tk_DestroyWindow((Tk_Window) winPtr);
            return (Tk_Window) NULL;
        }
    }
    TkWmNewWindow(winPtr);
    return (Tk_Window) winPtr;
}
\f
/*
 *----------------------------------------------------------------------
 *
 * GetScreen --
 *
 *      Given a string name for a display-plus-screen, find the
 *      TkDisplay structure for the display and return the screen
 *      number too.
 *
 * Results:
 *      The return value is a pointer to information about the display,
 *      or NULL if the display couldn't be opened.  In this case, an
 *      error message is left in interp->result.  The location at
 *      *screenPtr is overwritten with the screen number parsed from
 *      screenName.
 *
 * Side effects:
 *      A new connection is opened to the display if there is no
 *      connection already.  A new TkDisplay data structure is also
 *      setup, if necessary.
 *
 *----------------------------------------------------------------------
 */

static TkDisplay *
GetScreen(interp, screenName, screenPtr)
    Tcl_Interp *interp;         /* Place to leave error message. */
    char *screenName;           /* Name for screen.  NULL or empty means
                                 * use DISPLAY envariable. */
    int *screenPtr;             /* Where to store screen number. */
{
    register TkDisplay *dispPtr;
    char *p;
    int length, screenId;

    /*
     * Separate the screen number from the rest of the display
     * name.  ScreenName is assumed to have the syntax
     * <display>.<screen> with the dot and the screen being
     * optional.
     */

    if ((screenName == NULL) || (screenName[0] == '\0')) {
        screenName = getenv("DISPLAY");
        if (screenName == NULL) {
            interp->result =
                    "no display name and no $DISPLAY environment variable";
            return (TkDisplay *) NULL;
        }
    }
    length = strlen(screenName);
    screenId = 0;
    p = screenName+length-1;
    while (isdigit(*p) && (p != screenName)) {
        p--;
    }
    if ((*p == '.') && (p[1] != '\0')) {
        length = p - screenName;
        screenId = strtoul(p+1, (char **) NULL, 10);
    }

    /*
     * See if we already have a connection to this display.  If not,
     * then open a new connection.
     */

    for (dispPtr = tkDisplayList; ; dispPtr = dispPtr->nextPtr) {
        if (dispPtr == NULL) {
            Display *display = NULL;

            display = XOpenDisplay(screenName);

            if (display == NULL) {
                Tcl_AppendResult(interp, "couldn't connect to display \"",
                        screenName, "\"", (char *) NULL);
                return (TkDisplay *) NULL;
            }
            if (getenv("XSYNCHRONIZE") != NULL) {
              XSynchronize(display, 1);
            }
            tk_Displays++;
            dispPtr = (TkDisplay *) ckalloc(sizeof(TkDisplay));
            dispPtr->display = display;
            dispPtr->nextPtr = tkDisplayList;
            dispPtr->name = (char *) ckalloc((unsigned) (length+1));
            dispPtr->lastEventTime = CurrentTime;
            strncpy(dispPtr->name, screenName, length);
            dispPtr->mouseMainPtr = NULL;
            dispPtr->name[length] = '\0';
            dispPtr->symsPerCode = 0;
            dispPtr->errorPtr = NULL;
            dispPtr->deleteCount = 0;
            dispPtr->commWindow = NULL;
            dispPtr->selectionOwner = NULL;
            dispPtr->selectionSerial = 0;
            dispPtr->multipleAtom = None;
            dispPtr->atomInit = 0;
            dispPtr->modeModMask = 0;
            dispPtr->metaModMask = 0;
            dispPtr->altModMask = 0;
            dispPtr->cursorFont = None;
            dispPtr->grabWinPtr = NULL;
            dispPtr->ungrabWinPtr = NULL;
            dispPtr->buttonWinPtr = NULL;
            dispPtr->pointerWinPtr = NULL;
            dispPtr->serverWinPtr = NULL;
            dispPtr->grabFlags = 0;
            dispPtr->focusPtr = NULL;
            tkDisplayList = dispPtr;
            Tk_CreateFileHandler(ConnectionNumber(display),
                    TK_READABLE, (void (*)()) NULL,
                    (ClientData) display);
            break;
        }
        if ((strncmp(dispPtr->name, screenName, length) == 0)
                && (dispPtr->name[length] == '\0')) {
            break;
        }
    }
    if (screenId >= ScreenCount(dispPtr->display)) {
        sprintf(interp->result, "bad screen number \"%d\"", screenId);
        return (TkDisplay *) NULL;
    }
    *screenPtr = screenId;
    return dispPtr;
}
\f
/*
 *--------------------------------------------------------------
 *
 * NewWindow --
 *
 *      This procedure creates and initializes a TkWindow structure.
 *
 * Results:
 *      The return value is a pointer to the new window.
 *
 * Side effects:
 *      A new window structure is allocated and all its fields are
 *      initialized.
 *
 *--------------------------------------------------------------
 */

static TkWindow *
NewWindow(dispPtr, screenNum)
    TkDisplay *dispPtr;         /* Display associated with new window. */
    int screenNum;              /* Index of screen for new window. */
{
    register TkWindow *winPtr;

    winPtr = (TkWindow *) ckalloc(sizeof(TkWindow));
    winPtr->display = dispPtr->display;
    winPtr->dispPtr = dispPtr;
    winPtr->screenNum = screenNum;
    winPtr->window = None;
    winPtr->childList = NULL;
    winPtr->parentPtr = NULL;
    winPtr->nextPtr = NULL;
    winPtr->mainPtr = NULL;
    winPtr->pathName = NULL;
    winPtr->nameUid = NULL;
    winPtr->classUid = NULL;
    winPtr->changes = defChanges;
    winPtr->dirtyChanges = CWX|CWY|CWWidth|CWHeight|CWBorderWidth;
    winPtr->atts = defAtts;
    winPtr->dirtyAtts = CWEventMask;
    winPtr->flags = 0;
    winPtr->handlerList = NULL;
    winPtr->focusProc = NULL;
    winPtr->focusData = NULL;
    winPtr->optionLevel = -1;
    winPtr->selHandlerList = NULL;
    winPtr->selClearProc = NULL;
    winPtr->selClearData = NULL;
    winPtr->geomProc = NULL;
    winPtr->geomData = NULL;
    winPtr->reqWidth = winPtr->reqHeight = 0;
    winPtr->internalBorderWidth = 0;
    winPtr->wmInfoPtr = NULL;
    return winPtr;
}
\f
/*
 *----------------------------------------------------------------------
 *
 * NameWindow --
 *
 *      This procedure is invoked to give a window a name and insert
 *      the window into the hierarchy associated with a particular
 *      application.
 *
 * Results:
 *      A standard Tcl return value.
 *
 * Side effects:
 *      See above.
 *
 *----------------------------------------------------------------------
 */

static int
NameWindow(interp, winPtr, parentPtr, name)
    Tcl_Interp *interp;         /* Interpreter to use for error reporting. */
    register TkWindow *winPtr;  /* Window that is to be named and inserted. */
    TkWindow *parentPtr;        /* Pointer to logical parent for winPtr
                                 * (used for naming, options, etc.). */
    char *name;                 /* Name for winPtr;   must be unique among
                                 * parentPtr's children. */
{
#define FIXED_SIZE 200
    char staticSpace[FIXED_SIZE];
    char *pathName;
    int new;
    Tcl_HashEntry *hPtr;
    int length1, length2;

    /*
     * Setup all the stuff except name right away, then do the name stuff
     * last.  This is so that if the name stuff fails, everything else
     * will be properly initialized (needed to destroy the window cleanly
     * after the naming failure).
     */
    winPtr->parentPtr = parentPtr;
    winPtr->nextPtr = parentPtr->childList;
    parentPtr->childList = winPtr;
    winPtr->mainPtr = parentPtr->mainPtr;
    winPtr->nameUid = Tk_GetUid(name);

    /*
     * To permit names of arbitrary length, must be prepared to malloc
     * a buffer to hold the new path name.  To run fast in the common
     * case where names are short, use a fixed-size buffer on the
     * stack.
     */

    length1 = strlen(parentPtr->pathName);
    length2 = strlen(name);
    if ((length1+length2+2) <= FIXED_SIZE) {
        pathName = staticSpace;
    } else {
        pathName = (char *) ckalloc((unsigned) (length1+length2+2));
    }
    if (length1 == 1) {
        pathName[0] = '.';
        strcpy(pathName+1, name);
    } else {
        strcpy(pathName, parentPtr->pathName);
        pathName[length1] = '.';
        strcpy(pathName+length1+1, name);
    }
    hPtr = Tcl_CreateHashEntry(&parentPtr->mainPtr->nameTable, pathName, &new);
    if (pathName != staticSpace) {
        ckfree(pathName);
    }
    if (!new) {
        Tcl_AppendResult(interp, "window name \"", name,
                "\" already exists in parent", (char *) NULL);
        return TCL_ERROR;
    }
    Tcl_SetHashValue(hPtr, winPtr);
    winPtr->pathName = Tcl_GetHashKey(&parentPtr->mainPtr->nameTable, hPtr);
    return TCL_OK;
}
\f
/*
 *----------------------------------------------------------------------
 *
 * Tk_CreateMainWindow --
 *
 *      Make a new main window.  A main window is a special kind of
 *      top-level window used as the outermost window in an
 *      application.
 *
 * Results:
 *      The return value is a token for the new window, or NULL if
 *      an error prevented the new window from being created.  If
 *      NULL is returned, an error message will be left in
 *      interp->result.
 *
 * Side effects:
 *      A new window structure is allocated locally;  "interp" is
 *      associated with the window and registered for "send" commands
 *      under "baseName".  BaseName may be extended with an instance
 *      number in the form "#2" if necessary to make it globally
 *      unique.  Tk-related commands are bound into interp.  An X
 *      window is NOT initially created, but will be created the
 *      first time the window is mapped.
 *
 *----------------------------------------------------------------------
 */

Tk_Window
Tk_CreateMainWindow(interp, screenName, baseName)
    Tcl_Interp *interp;         /* Interpreter to use for error reporting. */
    char *screenName;           /* Name of screen on which to create
                                 * window.  Empty or NULL string means
                                 * use DISPLAY environment variable. */
    char *baseName;             /* Base name for application;  usually of the
                                 * form "prog instance". */
{
    Tk_Window tkwin;
    int result, dummy;
    Tcl_HashEntry *hPtr;
    register TkMainInfo *mainPtr;
    register TkWindow *winPtr;
    register TkCmd *cmdPtr;

    /*
     * Create the basic TkWindow structure.
     */

    tkwin = CreateTopLevelWindow(interp, (Tk_Window) NULL, baseName,
            screenName);
    if (tkwin == NULL) {
        return NULL;
    }

    /*
     * Create the TkMainInfo structure for this application, and set
     * up name-related information for the new window.
     */

    winPtr = (TkWindow *) tkwin;
    mainPtr = (TkMainInfo *) ckalloc(sizeof(TkMainInfo));
    mainPtr->winPtr = winPtr;
    mainPtr->interp = interp;
    Tcl_InitHashTable(&mainPtr->nameTable, TCL_STRING_KEYS);
    mainPtr->bindingTable = Tk_CreateBindingTable(interp);
/* XXX: FOCUS */
/*    mainPtr->focusPtr = NULL; */
    mainPtr->optionRootPtr = NULL;
    winPtr->mainPtr = mainPtr;
    hPtr = Tcl_CreateHashEntry(&mainPtr->nameTable, ".", &dummy);
    Tcl_SetHashValue(hPtr, winPtr);
    winPtr->pathName = Tcl_GetHashKey(&mainPtr->nameTable, hPtr);

    /*
     * Register the interpreter for "send" purposes.  If baseName isn't
     * already unique, find a unique suffix to add to it to make it
     * unique.  Change the window's name to contain the suffix.
     */

    result = Tk_RegisterInterp(interp, baseName, tkwin);
    if (result == TCL_OK) {
        winPtr->nameUid = Tk_GetUid(baseName);
    } else {
        char newName[110];
        int i;

        for (i = 2; ; i++) {
            sprintf(newName, "%.100s #%d", baseName, i);
            Tcl_SetResult(interp, (char *) NULL, TCL_STATIC);
            result = Tk_RegisterInterp(interp, newName, tkwin);
            if (result == TCL_OK) {
                break;
            }
            if (i >= 100) {
                Tcl_SetResult(interp,
                        "couldn't generate unique name to register application",
                        TCL_STATIC);
                Tk_DestroyWindow(tkwin);
            }
        }
        winPtr->nameUid = Tk_GetUid(newName);
    }

    /*
     * Bind in Tk's commands.
     */

    for (cmdPtr = commands; cmdPtr->name != NULL; cmdPtr++) {
        Tcl_CreateCommand(interp, cmdPtr->name, cmdPtr->cmdProc,
                (ClientData) tkwin, (void (*)()) NULL);
    }

    /*
     * Set variables for the intepreter.
     */

    Tcl_SetVar(interp, "tk_library", TK_Library, TCL_GLOBAL_ONLY);
    Tcl_SetVar(interp, "tk_version", TK_VERSION, TCL_GLOBAL_ONLY);
    Tcl_SetVar(interp, "tkVersion", TK_VERSION, TCL_GLOBAL_ONLY);

    tk_NumMainWindows++;
    return tkwin;
}
\f
/*
 *--------------------------------------------------------------
 *
 * Tk_CreateWindow --
 *
 *      Create a new internal or top-level window as a child of an
 *      existing window.
 *
 * Results:
 *      The return value is a token for the new window.  This
 *      is not the same as X's token for the window.  If an error
 *      occurred in creating the window (e.g. no such display or
 *      screen), then an error message is left in interp->result and
 *      NULL is returned.
 *
 * Side effects:
 *      A new window structure is allocated locally.  An X
 *      window is not initially created, but will be created
 *      the first time the window is mapped.
 *
 *--------------------------------------------------------------
 */

Tk_Window
Tk_CreateWindow(interp, parent, name, screenName)
    Tcl_Interp *interp;         /* Interpreter to use for error reporting.
                                 * Interp->result is assumed to be
                                 * initialized by the caller. */
    Tk_Window parent;           /* Token for parent of new window. */
    char *name;                 /* Name for new window.  Must be unique
                                 * among parent's children. */
    char *screenName;           /* If NULL, new window will be internal on
                                 * same screen as its parent.  If non-NULL,
                                 * gives name of screen on which to create
                                 * new window;  window will be a top-level
                                 * window. */
{
    TkWindow *parentPtr = (TkWindow *) parent;
    TkWindow *winPtr;

    if (screenName == NULL) {
        winPtr = NewWindow(parentPtr->dispPtr, parentPtr->screenNum);
        if (NameWindow(interp, winPtr, parentPtr, name) != TCL_OK) {
            Tk_DestroyWindow((Tk_Window) winPtr);
            return NULL;
        } else {
            return (Tk_Window) winPtr;
        }
    } else {
/*
 * This is a fix for dvx XOpenDisplay... display name conformalization
 * bugs...
 */
        char dsp[256];
        int len;

        strcpy(dsp, screenName);
        len = strlen(dsp);
        if (len && (dsp[len -1] == '.'))
            dsp[len -1] = '\0';

        return CreateTopLevelWindow(interp, parent, name, dsp);
    }
}
\f
/*
 *----------------------------------------------------------------------
 *
 * Tk_CreateWindowFromPath --
 *
 *      This procedure is similar to Tk_CreateInternalWindow except
 *      that it uses a path name to create the window, rather than
 *      a parent and a child name.
 *
 * Results:
 *      The return value is a token for the new window.  This
 *      is not the same as X's token for the window.  If an error
 *      occurred in creating the window (e.g. no such display or
 *      screen), then an error message is left in interp->result and
 *      NULL is returned.
 *
 * Side effects:
 *      A new window structure is allocated locally.  An X
 *      window is not initially created, but will be created
 *      the first time the window is mapped.
 *
 *----------------------------------------------------------------------
 */

Tk_Window
Tk_CreateWindowFromPath(interp, tkwin, pathName, screenName)
    Tcl_Interp *interp;         /* Interpreter to use for error reporting.
                                 * Interp->result is assumed to be
                                 * initialized by the caller. */
    Tk_Window tkwin;            /* Token for any window in application
                                 * that is to contain new window. */
    char *pathName;             /* Path name for new window within the
                                 * application of tkwin.  The parent of
                                 * this window must already exist, but
                                 * the window itself must not exist. */
    char *screenName;           /* If NULL, new window will be on same
                                 * screen as its parent.  If non-NULL,
                                 * gives name of screen on which to create
                                 * new window;  window will be a top-level
                                 * window. */
{
#define FIXED_SPACE 5
    char fixedSpace[FIXED_SPACE+1];
    char *p;
    Tk_Window parent;
    int numChars;

    /*
     * Strip the parent's name out of pathName (it's everything up
     * to the last dot).  There are two tricky parts: (a) must
     * copy the parent's name somewhere else to avoid modifying
     * the pathName string (for large names, space for the copy
     * will have to be malloc'ed);  (b) must special-case the
     * situation where the parent is ".".
     */

    p = strrchr(pathName, '.');
    if (p == NULL) {
        Tcl_AppendResult(interp, "bad window path name \"", pathName,
                "\"", (char *) NULL);
        return NULL;
    }
    numChars = p-pathName;
    if (numChars > FIXED_SPACE) {
        p = (char *) ckalloc((unsigned) (numChars+1));
    } else {
        p = fixedSpace;
    }
    if (numChars == 0) {
        *p = '.';
        p[1] = '\0';
    } else {
        strncpy(p, pathName, numChars);
        p[numChars] = '\0';
    }

    /*
     * Find the parent window.
     */

    parent = Tk_NameToWindow(interp, p, tkwin);
    if (p != fixedSpace) {
        ckfree(p);
    }
    if (parent == NULL) {
        return NULL;
    }

    /*
     * Create the window.
     */

    if (screenName == NULL) {
        TkWindow *parentPtr = (TkWindow *) parent;
        TkWindow *winPtr;

        winPtr = NewWindow(parentPtr->dispPtr, parentPtr->screenNum);
        if (NameWindow(interp, winPtr, parentPtr, pathName+numChars+1)
                != TCL_OK) {
            Tk_DestroyWindow((Tk_Window) winPtr);
            return NULL;
        } else {
            return (Tk_Window) winPtr;
        }
    } else {
        return CreateTopLevelWindow(interp, parent, pathName+numChars+1,
                screenName);
    }
}
\f
/*
 *--------------------------------------------------------------
 *
 * Tk_DestroyWindow --
 *
 *      Destroy an existing window.  After this call, the caller
 *      should never again use the token.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The window is deleted, along with all of its children.
 *      Relevant callback procedures are invoked.
 *
 *--------------------------------------------------------------
 */

void
Tk_DestroyWindow(tkwin)
    Tk_Window tkwin;            /* Window to destroy. */
{
    register TkWindow *winPtr = (TkWindow *) tkwin;
    XEvent event;

    /*
     * Recursively destroy children.  The TK_RECURSIVE_DESTROY
     * flags means that the child's window needn't be explicitly
     * destroyed (the destroy of the parent already did it), nor
     * does it need to be removed from its parent's child list,
     * since the parent is being destroyed too.
     */

    while (winPtr->childList != NULL) {
        winPtr->childList->flags |= TK_RECURSIVE_DESTROY;
        Tk_DestroyWindow((Tk_Window) winPtr->childList);
    }

    /*
     * Generate a DestroyNotify event.  In order for the DestroyNotify
     * event to be processed correctly, need to make sure the window
     * exists.  This is a bit of a kludge, and may be unnecessarily
     * expensive, but without it no event handlers will get called for
     * windows that don't exist yet.
     */

    if (winPtr->window == None) {
        Tk_MakeWindowExist(tkwin);
    }
    winPtr->flags |= TK_ALREADY_DEAD;
    event.type = DestroyNotify;
    event.xdestroywindow.serial =
            LastKnownRequestProcessed(winPtr->display);
    event.xdestroywindow.send_event = False;
    event.xdestroywindow.display = winPtr->display;
    event.xdestroywindow.event = winPtr->window;
    event.xdestroywindow.window = winPtr->window;
    Tk_HandleEvent(&event);

    /*
     * Cleanup the data structures associated with this window.
     * No need to destroy windows during recursive destroys, since
     * that will happen automatically when the parent window is
     * destroyed (not true for top-level windows:  must destroy
     * them explicitly).
     */

    if (winPtr->window != None) {
        if (!(winPtr->flags & TK_RECURSIVE_DESTROY)
                || (winPtr->flags & TK_TOP_LEVEL)) {
            XDestroyWindow(winPtr->display, winPtr->window);
        }
        XDeleteContext(winPtr->display, winPtr->window, tkWindowContext);
        winPtr->window = None;
    }
    if (winPtr->parentPtr != NULL) {
        if (winPtr->parentPtr->childList == winPtr) {
            winPtr->parentPtr->childList = winPtr->nextPtr;
        } else {
            register TkWindow *winPtr2;
    
            for (winPtr2 = winPtr->parentPtr->childList; ;
                    winPtr2 = winPtr2->nextPtr) {
                if (winPtr2 == NULL) {
                    panic("Tk_DestroyWindow couldn't find child in parent (deleted twice?)");
                    break;
                }
                if (winPtr2->nextPtr == winPtr) {
                    winPtr2->nextPtr = winPtr->nextPtr;
                    break;
                }
            }
        }
    }
    TkEventDeadWindow(winPtr);
    TkOptionDeadWindow(winPtr);
    TkSelDeadWindow(winPtr);
    if (winPtr->flags & TK_TOP_LEVEL) {
        TkWmDeadWindow(winPtr);
    }
    TkGrabDeadWindow(winPtr);
    if (winPtr->mainPtr != NULL) {
        Tk_DeleteAllBindings(winPtr->mainPtr->bindingTable,
                (ClientData) winPtr->pathName);
        if (winPtr->pathName != NULL) {
            Tcl_DeleteHashEntry(Tcl_FindHashEntry(&winPtr->mainPtr->nameTable,
                    winPtr->pathName));
        }
        if (winPtr->mainPtr->winPtr == winPtr) {
            register TkCmd *cmdPtr;

            /*
             * Deleting a main window.  Delete the TkMainInfo structure too
             * and replace all of Tk's commands with dummy commands that
             * return errors.  Also delete the "send" command to unregister
             * the interpreter.
             */

            for (cmdPtr = commands; cmdPtr->name != NULL; cmdPtr++) {
                Tcl_CreateCommand(winPtr->mainPtr->interp, cmdPtr->name,
                        TkDeadAppCmd, (ClientData) NULL, (void (*)()) NULL);
            }
            Tcl_CreateCommand(winPtr->mainPtr->interp, "send",
                    TkDeadAppCmd, (ClientData) NULL, (void (*)()) NULL);
            Tcl_DeleteHashTable(&winPtr->mainPtr->nameTable);
            Tk_DeleteBindingTable(winPtr->mainPtr->bindingTable);
            ckfree((char *) winPtr->mainPtr);
            tk_NumMainWindows--;
        }
    }
    ckfree((char *) winPtr);
}
\f
/*
 *--------------------------------------------------------------
 *
 * Tk_MapWindow --
 *
 *      Map a window within its parent.  This may require the
 *      window and/or its parents to actually be created.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The given window will be mapped.  Windows may also
 *      be created.
 *
 *--------------------------------------------------------------
 */

void
Tk_MapWindow(tkwin)
    Tk_Window tkwin;            /* Token for window to map. */
{
    register TkWindow *winPtr = (TkWindow *) tkwin;

    if (winPtr->flags & TK_MAPPED) {
        return;
    }
    if (winPtr->window == None) {
        Tk_MakeWindowExist(tkwin);
    }
    if (winPtr->flags & TK_TOP_LEVEL) {
        if (!TkWmMapWindow(winPtr)) {
            return;
        }
    } else {
        /*
         * Don't set the mapped flag for top-level windows:  TkWmMapWindow
         * does it if appropriate (e.g. if the window is going to be non-
         * iconic).
         */

        winPtr->flags |= TK_MAPPED;
    }
    XMapWindow(winPtr->display, winPtr->window);
    if (!(winPtr->flags & TK_TOP_LEVEL)) {
        XEvent event;

        event.type = MapNotify;
        event.xmap.serial = LastKnownRequestProcessed(winPtr->display);
        event.xmap.send_event = False;
        event.xmap.display = winPtr->display;
        event.xmap.event = winPtr->window;
        event.xmap.window = winPtr->window;
        event.xmap.override_redirect = winPtr->atts.override_redirect;
        Tk_HandleEvent(&event);
    }
}
\f
/*
 *--------------------------------------------------------------
 *
 * Tk_MakeWindowExist --
 *
 *      Ensure that a particular window actually exists.  This
 *      procedure shouldn't normally need to be invoked from
 *      outside the Tk package, but may be needed if someone
 *      wants to manipulate a window before mapping it.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      When the procedure returns, the X window associated with
 *      tkwin is guaranteed to exist.  This may require the
 *      window's ancestors to be created also.
 *
 *--------------------------------------------------------------
 */

void
Tk_MakeWindowExist(tkwin)
    Tk_Window tkwin;            /* Token for window. */
{
    register TkWindow *winPtr = (TkWindow *) tkwin;
    Window parent;

    if (winPtr->window != None) {
        return;
    }

    if (winPtr->flags & TK_TOP_LEVEL) {
        /*
         * workaround by dhopkins for OLPC Micropolis gtk.Socket integration. 
         */

        if (tk_RootWindow) {
            parent = 
                tk_RootWindow;
        } else {
            parent = 
                XRootWindow(winPtr->display, winPtr->screenNum);
        }

    } else {
        if (winPtr->parentPtr->window == None) {
            Tk_MakeWindowExist((Tk_Window) winPtr->parentPtr);
        }
        parent = winPtr->parentPtr->window;
    }

/* workaround to support non-default colormaps */
#if 0
    winPtr->window = XCreateWindow(winPtr->display, parent,
            winPtr->changes.x, winPtr->changes.y,
            winPtr->changes.width, winPtr->changes.height,
            winPtr->changes.border_width, CopyFromParent,
            InputOutput, CopyFromParent, winPtr->dirtyAtts,
            &winPtr->atts);
#else
    { Screen *scr = ScreenOfDisplay(winPtr->display, winPtr->screenNum);

      winPtr->dirtyAtts |= CWColormap | CWBorderPixmap;
      winPtr->atts.colormap = Tk_DefaultColormap(scr);
      winPtr->atts.border_pixmap = Tk_DefaultPixmap(scr);

      winPtr->window = XCreateWindow(winPtr->display, parent,
          winPtr->changes.x, winPtr->changes.y,
          winPtr->changes.width, winPtr->changes.height,
          winPtr->changes.border_width,
          Tk_DefaultDepth(scr),
          InputOutput,
          Tk_DefaultVisual(scr),
          winPtr->dirtyAtts, &winPtr->atts);
    }
#endif

    XSaveContext(winPtr->display, winPtr->window, tkWindowContext,
            (void *) winPtr);
    winPtr->dirtyAtts = 0;
    winPtr->dirtyChanges &= ~(CWX|CWY|CWWidth|CWHeight|CWBorderWidth);
    if (winPtr->dirtyChanges != 0) {
        XConfigureWindow(winPtr->display, winPtr->window,
                winPtr->dirtyChanges, &winPtr->changes);
        winPtr->dirtyChanges = 0;
    }

    /*
     * Issue a ConfigureNotify event if there were deferred configuration
     * changes.
     */

    if (winPtr->flags & TK_NEED_CONFIG_NOTIFY) {
        winPtr->flags &= ~TK_NEED_CONFIG_NOTIFY;
        DoConfigureNotify(winPtr);
    }
}
\f
/*
 *--------------------------------------------------------------
 *
 * Tk_UnmapWindow, etc. --
 *
 *      There are several procedures under here, each of which
 *      mirrors an existing X procedure.  In addition to performing
 *      the functions of the corresponding procedure, each
 *      procedure also updates the local window structure and
 *      synthesizes an X event (if the window's structure is being
 *      managed internally).
 *
 * Results:
 *      See the manual entries.
 *
 * Side effects:
 *      See the manual entries.
 *
 *--------------------------------------------------------------
 */

void
Tk_UnmapWindow(tkwin)
    Tk_Window tkwin;            /* Token for window to unmap. */
{
    register TkWindow *winPtr = (TkWindow *) tkwin;

    if (!(winPtr->flags & TK_MAPPED)) {
        return;
    }
    winPtr->flags &= ~TK_MAPPED;
    XUnmapWindow(winPtr->display, winPtr->window);
    if (!(winPtr->flags & TK_TOP_LEVEL)) {
        XEvent event;

        event.type = UnmapNotify;
        event.xunmap.serial = LastKnownRequestProcessed(winPtr->display);
        event.xunmap.send_event = False;
        event.xunmap.display = winPtr->display;
        event.xunmap.event = winPtr->window;
        event.xunmap.window = winPtr->window;
        event.xunmap.from_configure = False;
        Tk_HandleEvent(&event);
    }
}

void
Tk_ConfigureWindow(tkwin, valueMask, valuePtr)
    Tk_Window tkwin;            /* Window to re-configure. */
    unsigned int valueMask;     /* Mask indicating which parts of
                                 * *valuePtr are to be used. */
    XWindowChanges *valuePtr;   /* New values. */
{
    register TkWindow *winPtr = (TkWindow *) tkwin;

    if ((winPtr->window == None) || !(winPtr->flags & TK_TOP_LEVEL)) {
        if (valueMask & CWX) {
            winPtr->changes.x = valuePtr->x;
        }
        if (valueMask & CWY) {
            winPtr->changes.y = valuePtr->y;
        }
        if (valueMask & CWWidth) {
            winPtr->changes.width = valuePtr->width;
        }
        if (valueMask & CWHeight) {
            winPtr->changes.height = valuePtr->height;
        }
        if (valueMask & CWBorderWidth) {
            winPtr->changes.border_width = valuePtr->border_width;
        }
        if (valueMask & CWSibling) {
            winPtr->changes.sibling = valuePtr->sibling;
        }
        if (valueMask & CWStackMode) {
            winPtr->changes.stack_mode = valuePtr->stack_mode;
        }
    }

    if (winPtr->window != None) {
        XConfigureWindow(winPtr->display, winPtr->window,
                valueMask, valuePtr);
        if (!(winPtr->flags & TK_TOP_LEVEL)) {
            DoConfigureNotify(winPtr);
        }
    } else {
        winPtr->dirtyChanges |= valueMask;
        winPtr->flags |= TK_NEED_CONFIG_NOTIFY;
    }
}

void
Tk_MoveWindow(tkwin, x, y)
    Tk_Window tkwin;            /* Window to move. */
    int x, y;                   /* New location for window (within
                                 * parent). */
{
    register TkWindow *winPtr = (TkWindow *) tkwin;

    if (winPtr->window != None) {
        XMoveWindow(winPtr->display, winPtr->window, x, y);
        if (!(winPtr->flags & TK_TOP_LEVEL)) {
            winPtr->changes.x = x;
            winPtr->changes.y = y;
            DoConfigureNotify(winPtr);
        }
    } else {
        winPtr->changes.x = x;
        winPtr->changes.y = y;
        winPtr->dirtyChanges |= CWX|CWY;
        winPtr->flags |= TK_NEED_CONFIG_NOTIFY;
    }
}

void
Tk_ResizeWindow(tkwin, width, height)
    Tk_Window tkwin;            /* Window to resize. */
    unsigned int width, height; /* New dimensions for window. */
{
    register TkWindow *winPtr = (TkWindow *) tkwin;

    if (winPtr->window != None) {
        XResizeWindow(winPtr->display, winPtr->window, width, height);
        if (!(winPtr->flags & TK_TOP_LEVEL)) {
            winPtr->changes.width = width;
            winPtr->changes.height = height;
            DoConfigureNotify(winPtr);
        }
    } else {
        winPtr->changes.width = width;
        winPtr->changes.height = height;
        winPtr->dirtyChanges |= CWWidth|CWHeight;
        winPtr->flags |= TK_NEED_CONFIG_NOTIFY;
    }
}

void
Tk_MoveResizeWindow(tkwin, x, y, width, height)
    Tk_Window tkwin;            /* Window to move and resize. */
    int x, y;                   /* New location for window (within
                                 * parent). */
    unsigned int width, height; /* New dimensions for window. */
{
    register TkWindow *winPtr = (TkWindow *) tkwin;

    if (winPtr->window != None) {
        XMoveResizeWindow(winPtr->display, winPtr->window,
                x, y, width, height);
        if (!(winPtr->flags & TK_TOP_LEVEL)) {
            winPtr->changes.x = x;
            winPtr->changes.y = y;
            winPtr->changes.width = width;
            winPtr->changes.height = height;
            DoConfigureNotify(winPtr);
        }
    } else {
        winPtr->changes.x = x;
        winPtr->changes.y = y;
        winPtr->changes.width = width;
        winPtr->changes.height = height;
        winPtr->dirtyChanges |= CWX|CWY|CWWidth|CWHeight;
        winPtr->flags |= TK_NEED_CONFIG_NOTIFY;
    }
}

void
Tk_SetWindowBorderWidth(tkwin, width)
    Tk_Window tkwin;            /* Window to modify. */
    int width;                  /* New border width for window. */
{
    register TkWindow *winPtr = (TkWindow *) tkwin;

    winPtr->changes.border_width = width;
    if (winPtr->window != None) {
        XSetWindowBorderWidth(winPtr->display, winPtr->window, width);
        if (!(winPtr->flags & TK_TOP_LEVEL)) {
            DoConfigureNotify(winPtr);
        }
    } else {
        winPtr->dirtyChanges |= CWBorderWidth;
        winPtr->flags |= TK_NEED_CONFIG_NOTIFY;
    }
}

void
Tk_ChangeWindowAttributes(tkwin, valueMask, attsPtr)
    Tk_Window tkwin;            /* Window to manipulate. */
    unsigned long valueMask;    /* OR'ed combination of bits,
                                 * indicating which fields of
                                 * *attsPtr are to be used. */
    register XSetWindowAttributes *attsPtr;
                                /* New values for some attributes. */
{
    register TkWindow *winPtr = (TkWindow *) tkwin;

    if (valueMask & CWBackPixmap) {
        winPtr->atts.background_pixmap = attsPtr->background_pixmap;
    }
    if (valueMask & CWBackPixel) {
        winPtr->atts.background_pixel = attsPtr->background_pixel;
    }
    if (valueMask & CWBorderPixmap) {
        winPtr->atts.border_pixmap = attsPtr->border_pixmap;
    }
    if (valueMask & CWBorderPixel) {
        winPtr->atts.border_pixel = attsPtr->border_pixel;
    }
    if (valueMask & CWBitGravity) {
        winPtr->atts.bit_gravity = attsPtr->bit_gravity;
    }
    if (valueMask & CWWinGravity) {
        winPtr->atts.win_gravity = attsPtr->win_gravity;
    }
    if (valueMask & CWBackingStore) {
        winPtr->atts.backing_store = attsPtr->backing_store;
    }
    if (valueMask & CWBackingPlanes) {
        winPtr->atts.backing_planes = attsPtr->backing_planes;
    }
    if (valueMask & CWBackingPixel) {
        winPtr->atts.backing_pixel = attsPtr->backing_pixel;
    }
    if (valueMask & CWOverrideRedirect) {
        winPtr->atts.override_redirect = attsPtr->override_redirect;
    }
    if (valueMask & CWSaveUnder) {
        winPtr->atts.save_under = attsPtr->save_under;
    }
    if (valueMask & CWEventMask) {
        winPtr->atts.event_mask = attsPtr->event_mask;
    }
    if (valueMask & CWDontPropagate) {
        winPtr->atts.do_not_propagate_mask
                = attsPtr->do_not_propagate_mask;
    }
    if (valueMask & CWColormap) {
        winPtr->atts.colormap = attsPtr->colormap;
    }
    if (valueMask & CWCursor) {
        winPtr->atts.cursor = attsPtr->cursor;
    }

    if (winPtr->window != None) {
        XChangeWindowAttributes(winPtr->display, winPtr->window,
                valueMask, attsPtr);
    } else {
        winPtr->dirtyAtts |= valueMask;
    }
}

void
Tk_SetWindowBackground(tkwin, pixel)
    Tk_Window tkwin;            /* Window to manipulate. */
    unsigned long pixel;        /* Pixel value to use for
                                 * window's background. */
{
    register TkWindow *winPtr = (TkWindow *) tkwin;

    winPtr->atts.background_pixel = pixel;

    if (winPtr->window != None) {
        XSetWindowBackground(winPtr->display, winPtr->window, pixel);
    } else {
        winPtr->dirtyAtts = (winPtr->dirtyAtts & ~CWBackPixmap)
                | CWBackPixel;
    }
}

void
Tk_SetWindowBackgroundPixmap(tkwin, pixmap)
    Tk_Window tkwin;            /* Window to manipulate. */
    Pixmap pixmap;              /* Pixmap to use for window's
                                 * background. */
{
    register TkWindow *winPtr = (TkWindow *) tkwin;

    winPtr->atts.background_pixmap = pixmap;

    if (winPtr->window != None) {
        XSetWindowBackgroundPixmap(winPtr->display,
                winPtr->window, pixmap);
    } else {
        winPtr->dirtyAtts = (winPtr->dirtyAtts & ~CWBackPixel)
                | CWBackPixmap;
    }
}

void
Tk_SetWindowBorder(tkwin, pixel)
    Tk_Window tkwin;            /* Window to manipulate. */
    unsigned long pixel;        /* Pixel value to use for
                                 * window's border. */
{
    register TkWindow *winPtr = (TkWindow *) tkwin;

    winPtr->atts.border_pixel = pixel;

    if (winPtr->window != None) {
        XSetWindowBorder(winPtr->display, winPtr->window, pixel);
    } else {
        winPtr->dirtyAtts = (winPtr->dirtyAtts & ~CWBorderPixmap)
                | CWBorderPixel;
    }
}

void
Tk_SetWindowBorderPixmap(tkwin, pixmap)
    Tk_Window tkwin;            /* Window to manipulate. */
    Pixmap pixmap;              /* Pixmap to use for window's
                                 * border. */
{
    register TkWindow *winPtr = (TkWindow *) tkwin;

    winPtr->atts.border_pixmap = pixmap;

    if (winPtr->window != None) {
        XSetWindowBorderPixmap(winPtr->display,
                winPtr->window, pixmap);
    } else {
        winPtr->dirtyAtts = (winPtr->dirtyAtts & ~CWBorderPixel)
                | CWBorderPixmap;
    }
}

void
Tk_DefineCursor(tkwin, cursor)
    Tk_Window tkwin;            /* Window to manipulate. */
    Cursor cursor;              /* Cursor to use for window (may be None). */
{
    register TkWindow *winPtr = (TkWindow *) tkwin;

    winPtr->atts.cursor = cursor;

    if (winPtr->window != None) {
        XDefineCursor(winPtr->display, winPtr->window, cursor);
    } else {
        winPtr->dirtyAtts = winPtr->dirtyAtts | CWCursor;
    }
}

void
Tk_UndefineCursor(tkwin)
    Tk_Window tkwin;            /* Window to manipulate. */
{
    Tk_DefineCursor(tkwin, None);
}
\f
/*
 *----------------------------------------------------------------------
 *
 * DoConfigureNotify --
 *
 *      Generate a ConfigureNotify event describing the current
 *      configuration of a window.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      An event is generated and processed by Tk_HandleEvent.
 *
 *----------------------------------------------------------------------
 */

static void
DoConfigureNotify(winPtr)
    register TkWindow *winPtr;          /* Window whose configuration
                                         * was just changed. */
{
    XEvent event;

    event.type = ConfigureNotify;
    event.xconfigure.serial = LastKnownRequestProcessed(winPtr->display);
    event.xconfigure.send_event = False;
    event.xconfigure.display = winPtr->display;
    event.xconfigure.event = winPtr->window;
    event.xconfigure.window = winPtr->window;
    event.xconfigure.x = winPtr->changes.x;
    event.xconfigure.y = winPtr->changes.y;
    event.xconfigure.width = winPtr->changes.width;
    event.xconfigure.height = winPtr->changes.height;
    event.xconfigure.border_width = winPtr->changes.border_width;
    if (winPtr->changes.stack_mode == Above) {
        event.xconfigure.above = winPtr->changes.sibling;
    } else {
        event.xconfigure.above = None;
    }
    event.xconfigure.override_redirect = winPtr->atts.override_redirect;
    Tk_HandleEvent(&event);
}
\f
/*
 *----------------------------------------------------------------------
 *
 * Tk_SetClass --
 *
 *      This procedure is used to give a window a class.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      A new class is stored for tkwin, replacing any existing
 *      class for it.
 *
 *----------------------------------------------------------------------
 */

void
Tk_SetClass(tkwin, className)
    Tk_Window tkwin;            /* Token for window to assign class. */
    char *className;            /* New class for tkwin. */
{
    register TkWindow *winPtr = (TkWindow *) tkwin;

    winPtr->classUid = Tk_GetUid(className);
    if (winPtr->flags & TK_TOP_LEVEL) {
        TkWmSetClass(winPtr);
    }
}
\f
/*
 *----------------------------------------------------------------------
 *
 * Tk_NameToWindow --
 *
 *      Given a string name for a window, this procedure
 *      returns the token for the window, if there exists a
 *      window corresponding to the given name.
 *
 * Results:
 *      The return result is either a token for the window corresponding
 *      to "name", or else NULL to indicate that there is no such
 *      window.  In this case, an error message is left in interp->result.
 *
 * Side effects:
 *      None.
 *
 *----------------------------------------------------------------------
 */

Tk_Window
Tk_NameToWindow(interp, pathName, tkwin)
    Tcl_Interp *interp;         /* Where to report errors. */
    char *pathName;             /* Path name of window. */
    Tk_Window tkwin;            /* Token for window:  name is assumed to
                                 * belong to the same main window as tkwin. */
{
    Tcl_HashEntry *hPtr;

    hPtr = Tcl_FindHashEntry(&((TkWindow *) tkwin)->mainPtr->nameTable,
            pathName);
    if (hPtr == NULL) {
        Tcl_AppendResult(interp, "bad window path name \"",
                pathName, "\"", (char *) NULL);
        return NULL;
    }
    return (Tk_Window) Tcl_GetHashValue(hPtr);
}
\f
/*
 *----------------------------------------------------------------------
 *
 * Tk_DisplayName --
 *
 *      Return the textual name of a window's display.
 *
 * Results:
 *      The return value is the string name of the display associated
 *      with tkwin.
 *
 * Side effects:
 *      None.
 *
 *----------------------------------------------------------------------
 */

char *
Tk_DisplayName(tkwin)
    Tk_Window tkwin;            /* Window whose display name is desired. */
{
    return ((TkWindow *) tkwin)->dispPtr->name;
}