dispatch.c

远程桌面连接工具

/* $XConsortium: dispatch.c /main/195 1996/12/15 21:24:40 rws $ */
/* $XFree86: xc/programs/Xserver/dix/dispatch.c,v 3.7 1996/12/23 06:29:38 dawes Exp $ */
/************************************************************

Copyright (c) 1987, 1989  X Consortium

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
X CONSORTIUM BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Except as contained in this notice, the name of the X Consortium shall not be
used in advertising or otherwise to promote the sale, use or other dealings
in this Software without prior written authorization from the X Consortium.


Copyright 1987, 1989 by Digital Equipment Corporation, Maynard, Massachusetts.

                        All Rights Reserved

Permission to use, copy, modify, and distribute this software and its 
documentation for any purpose and without fee is hereby granted, 
provided that the above copyright notice appear in all copies and that
both that copyright notice and this permission notice appear in 
supporting documentation, and that the name of Digital not be
used in advertising or publicity pertaining to distribution of the
software without specific, written prior permission.  

DIGITAL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
DIGITAL BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
SOFTWARE.

********************************************************/

#include "windowstr.h"
#include "fontstruct.h"
#include "dixfontstr.h"
#include "gcstruct.h"
#include "selection.h"
#include "colormapst.h"
#include "cursorstr.h"
#include "scrnintstr.h"
#include "opaque.h"
#include "input.h"
#include "servermd.h"
#include "extnsionst.h"
#include "dixfont.h"
#include "dispatch.h"
#include "swaprep.h"
#include "swapreq.h"
#include "dixevents.h"
#ifdef XCSECURITY
#define _SECURITY_SERVER
#include "extensions/security.h"
#endif
#ifdef XAPPGROUP
#include "extensions/Xagsrv.h"
#endif

#define mskcnt ((MAXCLIENTS + 31) / 32)
#define BITMASK(i) (1 << ((i) & 31))
#define MASKIDX(i) ((i) >> 5)
#define MASKWORD(buf, i) buf[MASKIDX(i)]
#define BITSET(buf, i) MASKWORD(buf, i) |= BITMASK(i)
#define BITCLEAR(buf, i) MASKWORD(buf, i) &= ~BITMASK(i)
#define GETBIT(buf, i) (MASKWORD(buf, i) & BITMASK(i))

extern WindowPtr *WindowTable;
extern xConnSetupPrefix connSetupPrefix;
extern char *ConnectionInfo;

Selection *CurrentSelections;
int NumCurrentSelections;

extern CARD32 defaultScreenSaverTime;
extern CARD32 defaultScreenSaverInterval;
extern int  defaultScreenSaverBlanking;
extern int  defaultScreenSaverAllowExposures;
static ClientPtr grabClient;
#define GrabNone 0
#define GrabActive 1
#define GrabKickout 2
static int grabState = GrabNone;
static long grabWaiters[mskcnt];
CallbackListPtr ServerGrabCallback = NULL;
HWEventQueuePtr checkForInput[2];
extern int connBlockScreenStart;

#ifdef XKB
extern Bool noXkbExtension;
#endif

static void KillAllClients(
#if NeedFunctionPrototypes
    void
#endif
);

static void DeleteClientFromAnySelections(
#if NeedFunctionPrototypes
    ClientPtr /*client*/
#endif
);

#ifdef LBX
extern unsigned long  StandardRequestLength();
#endif

static int nextFreeClientID; /* always MIN free client ID */

static int	nClients;	/* number of authorized clients */

CallbackListPtr ClientStateCallback;
char dispatchException = 0;
char isItTimeToYield;

/* Various of the DIX function interfaces were not designed to allow
 * the client->errorValue to be set on BadValue and other errors.
 * Rather than changing interfaces and breaking untold code we introduce
 * a new global that dispatch can use.
 */
XID clientErrorValue;   /* XXX this is a kludge */

#define SAME_SCREENS(a, b) (\
    (a.pScreen == b.pScreen))

void
SetInputCheck(c0, c1)
    HWEventQueuePtr c0, c1;
{
    checkForInput[0] = c0;
    checkForInput[1] = c1;
}

void
UpdateCurrentTime()
{
    TimeStamp systime;

    /* To avoid time running backwards, we must call GetTimeInMillis before
     * calling ProcessInputEvents.
     */
    systime.months = currentTime.months;
    systime.milliseconds = GetTimeInMillis();
    if (systime.milliseconds < currentTime.milliseconds)
	systime.months++;
    if (*checkForInput[0] != *checkForInput[1])
	ProcessInputEvents();
    if (CompareTimeStamps(systime, currentTime) == LATER)
	currentTime = systime;
}

/* Like UpdateCurrentTime, but can't call ProcessInputEvents */
void
UpdateCurrentTimeIf()
{
    TimeStamp systime;

    systime.months = currentTime.months;
    systime.milliseconds = GetTimeInMillis();
    if (systime.milliseconds < currentTime.milliseconds)
	systime.months++;
    if (*checkForInput[0] == *checkForInput[1])
	currentTime = systime;
}

void
InitSelections()
{
    if (CurrentSelections)
	xfree(CurrentSelections);
    CurrentSelections = (Selection *)NULL;
    NumCurrentSelections = 0;
}

void 
FlushClientCaches(id)
    XID id;
{
    int i;
    register ClientPtr client;

    client = clients[CLIENT_ID(id)];
    if (client == NullClient)
        return ;
    for (i=0; i<currentMaxClients; i++)
    {
	client = clients[i];
        if (client != NullClient)
	{
            if (client->lastDrawableID == id)
	    {
		client->lastDrawableID = WindowTable[0]->drawable.id;
		client->lastDrawable = (DrawablePtr)WindowTable[0];
	    }
            else if (client->lastGCID == id)
	    {
                client->lastGCID = INVALID;
		client->lastGC = (GCPtr)NULL;
	    }
	}
    }
}

#define MAJOROP ((xReq *)client->requestBuffer)->reqType

void
Dispatch()
{
    register int        *clientReady;     /* array of request ready clients */
    register int	result;
    register ClientPtr	client;
    register int	nready;
    register HWEventQueuePtr* icheck = checkForInput;

    nextFreeClientID = 1;
    InitSelections();
    nClients = 0;

    clientReady = (int *) ALLOCATE_LOCAL(sizeof(int) * MaxClients);
    if (!clientReady)
	return;

    while (!dispatchException)
    {
        if (*icheck[0] != *icheck[1])
	{
	    ProcessInputEvents();
	    FlushIfCriticalOutputPending();
	}

	nready = WaitForSomething(clientReady);

       /***************** 
	*  Handle events in round robin fashion, doing input between 
	*  each round 
	*****************/

	while (!dispatchException && (--nready >= 0))
	{
	    client = clients[clientReady[nready]];
	    if (! client)
	    {
		/* KillClient can cause this to happen */
		continue;
	    }
	    /* GrabServer activation can cause this to be true */
	    if (grabState == GrabKickout)
	    {
		grabState = GrabActive;
		break;
	    }
	    isItTimeToYield = FALSE;
 
            requestingClient = client;
	    while (!isItTimeToYield)
	    {
	        if (*icheck[0] != *icheck[1])
		{
		    ProcessInputEvents();
		    FlushIfCriticalOutputPending();
		}
	   
		/* now, finally, deal with client requests */

	        result = ReadRequestFromClient(client);
	        if (result <= 0) 
	        {
		    if (result < 0)
			CloseDownClient(client);
		    break;
	        }

		client->sequence++;
#ifdef DEBUG
		if (client->requestLogIndex == MAX_REQUEST_LOG)
		    client->requestLogIndex = 0;
		client->requestLog[client->requestLogIndex] = MAJOROP;
		client->requestLogIndex++;
#endif
		if (result > (MAX_BIG_REQUEST_SIZE << 2))
		    result = BadLength;
		else
		    result = (* client->requestVector[MAJOROP])(client);
	    
		if (result != Success) 
		{
		    if (client->noClientException != Success)
                        CloseDownClient(client);
                    else
		        SendErrorToClient(client, MAJOROP,
					  MinorOpcodeOfRequest(client),
					  client->errorValue, result);
		    break;
	        }
	    }
	    FlushAllOutput();

	    requestingClient = NULL;
	}
	dispatchException &= ~DE_PRIORITYCHANGE;
    }
    KillAllClients();
    DEALLOCATE_LOCAL(clientReady);
    dispatchException &= ~DE_RESET;
}

#undef MAJOROP

/*ARGSUSED*/
int
ProcBadRequest(client)
    ClientPtr client;
{
    return (BadRequest);
}

int
ProcCreateWindow(client)
    register ClientPtr client;
{
    register WindowPtr pParent, pWin;
    REQUEST(xCreateWindowReq);
    int result;
    int len;

    REQUEST_AT_LEAST_SIZE(xCreateWindowReq);
    
    LEGAL_NEW_RESOURCE(stuff->wid, client);
    if (!(pParent = (WindowPtr)SecurityLookupWindow(stuff->parent, client,
						    SecurityWriteAccess)))
        return BadWindow;
    len = client->req_len - (sizeof(xCreateWindowReq) >> 2);
    if (Ones(stuff->mask) != len)
        return BadLength;
    if (!stuff->width || !stuff->height)
    {
	client->errorValue = 0;
        return BadValue;
    }
    pWin = CreateWindow(stuff->wid, pParent, stuff->x,
			      stuff->y, stuff->width, stuff->height, 
			      stuff->borderWidth, stuff->class,
			      stuff->mask, (XID *) &stuff[1], 
			      (int)stuff->depth, 
			      client, stuff->visual, &result);
    if (pWin)
    {
	Mask mask = pWin->eventMask;

	pWin->eventMask = 0; /* subterfuge in case AddResource fails */
	if (!AddResource(stuff->wid, RT_WINDOW, (pointer)pWin))
	    return BadAlloc;
	pWin->eventMask = mask;
    }
    if (client->noClientException != Success)
        return(client->noClientException);
    else
        return(result);
}

int
ProcChangeWindowAttributes(client)
    register ClientPtr client;
{
    register WindowPtr pWin;
    REQUEST(xChangeWindowAttributesReq);
    register int result;
    int len;

    REQUEST_AT_LEAST_SIZE(xChangeWindowAttributesReq);
    pWin = (WindowPtr)SecurityLookupWindow(stuff->window, client,
					   SecurityWriteAccess);
    if (!pWin)
        return(BadWindow);
    len = client->req_len - (sizeof(xChangeWindowAttributesReq) >> 2);
    if (len != Ones(stuff->valueMask))
        return BadLength;
    result =  ChangeWindowAttributes(pWin, 
				  stuff->valueMask, 
				  (XID *) &stuff[1], 
				  client);
    if (client->noClientException != Success)
        return(client->noClientException);
    else
        return(result);
}

int
ProcGetWindowAttributes(client)
    register ClientPtr client;
{
    register WindowPtr pWin;
    REQUEST(xResourceReq);
    xGetWindowAttributesReply wa;

    REQUEST_SIZE_MATCH(xResourceReq);
    pWin = (WindowPtr)SecurityLookupWindow(stuff->id, client,
					   SecurityReadAccess);
    if (!pWin)
        return(BadWindow);
    GetWindowAttributes(pWin, client, &wa);
    WriteReplyToClient(client, sizeof(xGetWindowAttributesReply), &wa);
    return(client->noClientException);
}

int
ProcDestroyWindow(client)
    register ClientPtr client;
{
    register WindowPtr pWin;
    REQUEST(xResourceReq);

    REQUEST_SIZE_MATCH(xResourceReq);
    pWin = (WindowPtr)SecurityLookupWindow(stuff->id, client,
					   SecurityDestroyAccess);
    if (!pWin)
        return(BadWindow);
    if (pWin->parent)
	FreeResource(stuff->id, RT_NONE);
    return(client->noClientException);
}

int
ProcDestroySubwindows(client)
    register ClientPtr client;
{
    register WindowPtr pWin;
    REQUEST(xResourceReq);

    REQUEST_SIZE_MATCH(xResourceReq);
    pWin = (WindowPtr)SecurityLookupWindow(stuff->id, client,
					   SecurityDestroyAccess);
    if (!pWin)
        return(BadWindow);
    DestroySubwindows(pWin, client);
    return(client->noClientException);
}

int
ProcChangeSaveSet(client)
    register ClientPtr client;
{
    register WindowPtr pWin;
    REQUEST(xChangeSaveSetReq);
    register int result;
		  
    REQUEST_SIZE_MATCH(xChangeSaveSetReq);
    pWin = (WindowPtr)SecurityLookupWindow(stuff->window, client,
					   SecurityReadAccess);
    if (!pWin)
        return(BadWindow);
    if (client->clientAsMask == (CLIENT_BITS(pWin->drawable.id)))
        return BadMatch;
    if ((stuff->mode == SetModeInsert) || (stuff->mode == SetModeDelete))
    {
        result = AlterSaveSetForClient(client, pWin, stuff->mode);
	if (client->noClientException != Success)
	    return(client->noClientException);
	else
            return(result);
    }
    else
    {
	client->errorValue = stuff->mode;
	return( BadValue );
    }
}

int
ProcReparentWindow(client)
    register ClientPtr client;
{
    register WindowPtr pWin, pParent;
    REQUEST(xReparentWindowReq);
    register int result;

    REQUEST_SIZE_MATCH(xReparentWindowReq);
    pWin = (WindowPtr)SecurityLookupWindow(stuff->window, client,
					   SecurityWriteAccess);
    if (!pWin)
        return(BadWindow);
    pParent = (WindowPtr)SecurityLookupWindow(stuff->parent, client,