resource.c

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    resources = (ResourcePtr *)xalloc(j * sizeof(ResourcePtr));
    if (!resources)
    {
	DEALLOCATE_LOCAL(tails);
	return;
    }
    for (rptr = resources, tptr = tails; --j >= 0; rptr++, tptr++)
    {
	*rptr = NullResource;
	*tptr = rptr;
    }
    clientTable[client].hashsize++;
    for (j = clientTable[client].buckets,
	 rptr = clientTable[client].resources;
	 --j >= 0;
	 rptr++)
    {
	for (res = *rptr; res; res = next)
	{
	    next = res->next;
	    res->next = NullResource;
	    tptr = &tails[Hash(client, res->id)];
	    **tptr = res;
	    *tptr = &res->next;
	}
    }
    DEALLOCATE_LOCAL(tails);
    clientTable[client].buckets *= 2;
    xfree(clientTable[client].resources);
    clientTable[client].resources = resources;
}

void
FreeResource(id, skipDeleteFuncType)
    XID id;
    RESTYPE skipDeleteFuncType;
{
    int		cid;
    register    ResourcePtr res;
    register	ResourcePtr *prev, *head;
    register	int *eltptr;
    int		elements;
    Bool	gotOne = FALSE;

    if (((cid = CLIENT_ID(id)) < MAXCLIENTS) && clientTable[cid].buckets)
    {
	head = &clientTable[cid].resources[Hash(cid, id)];
	eltptr = &clientTable[cid].elements;

	prev = head;
	while ( (res = *prev) )
	{
	    if (res->id == id)
	    {
		RESTYPE rtype = res->type;
		*prev = res->next;
		elements = --*eltptr;
		if (rtype & RC_CACHED)
		    FlushClientCaches(res->id);
		if (rtype != skipDeleteFuncType)
		    (*DeleteFuncs[rtype & TypeMask])(res->value, res->id);
		xfree(res);
		if (*eltptr != elements)
		    prev = head; /* prev may no longer be valid */
		gotOne = TRUE;
	    }
	    else
		prev = &res->next;
        }
	if(clients[cid] && (id == clients[cid]->lastDrawableID))
	{
	    clients[cid]->lastDrawable = (DrawablePtr)WindowTable[0];
	    clients[cid]->lastDrawableID = WindowTable[0]->drawable.id;
	}
    }
    if (!gotOne)
	FatalError("Freeing resource id=%X which isn't there", id);
}


void
FreeResourceByType(id, type, skipFree)
    XID id;
    RESTYPE type;
    Bool    skipFree;
{
    int		cid;
    register    ResourcePtr res;
    register	ResourcePtr *prev, *head;

    if (((cid = CLIENT_ID(id)) < MAXCLIENTS) && clientTable[cid].buckets)
    {
	head = &clientTable[cid].resources[Hash(cid, id)];

	prev = head;
	while ( (res = *prev) )
	{
	    if (res->id == id && res->type == type)
	    {
		*prev = res->next;
		if (type & RC_CACHED)
		    FlushClientCaches(res->id);
		if (!skipFree)
		    (*DeleteFuncs[type & TypeMask])(res->value, res->id);
		xfree(res);
		break;
	    }
	    else
		prev = &res->next;
        }
	if(clients[cid] && (id == clients[cid]->lastDrawableID))
	{
	    clients[cid]->lastDrawable = (DrawablePtr)WindowTable[0];
	    clients[cid]->lastDrawableID = WindowTable[0]->drawable.id;
	}
    }
}

/*
 * Change the value associated with a resource id.  Caller
 * is responsible for "doing the right thing" with the old
 * data
 */

Bool
ChangeResourceValue (id, rtype, value)
    XID	id;
    RESTYPE rtype;
    pointer value;
{
    int    cid;
    register    ResourcePtr res;

    if (((cid = CLIENT_ID(id)) < MAXCLIENTS) && clientTable[cid].buckets)
    {
	res = clientTable[cid].resources[Hash(cid, id)];

	for (; res; res = res->next)
	    if ((res->id == id) && (res->type == rtype))
	    {
		if (rtype & RC_CACHED)
		    FlushClientCaches(res->id);
		res->value = value;
		return TRUE;
	    }
    }
    return FALSE;
}

/* Note: if func adds or deletes resources, then func can get called
 * more than once for some resources.  If func adds new resources,
 * func might or might not get called for them.  func cannot both
 * add and delete an equal number of resources!
 */

void
FindClientResourcesByType(client, type, func, cdata)
    ClientPtr client;
    RESTYPE type;
    FindResType func;
    pointer cdata;
{
    register ResourcePtr *resources;
    register ResourcePtr this, next;
    int i, elements;
    register int *eltptr;

    if (!client)
	client = serverClient;

    resources = clientTable[client->index].resources;
    eltptr = &clientTable[client->index].elements;
    for (i = 0; i < clientTable[client->index].buckets; i++) 
    {
        for (this = resources[i]; this; this = next)
	{
	    next = this->next;
	    if (!type || this->type == type) {
		elements = *eltptr;
		(*func)(this->value, this->id, cdata);
		if (*eltptr != elements)
		    next = resources[i]; /* start over */
	    }
	}
    }
}

void
FreeClientNeverRetainResources(client)
    ClientPtr client;
{
    ResourcePtr *resources;
    ResourcePtr this;
    ResourcePtr *prev;
    int j;

    if (!client)
	return;

    resources = clientTable[client->index].resources;
    for (j=0; j < clientTable[client->index].buckets; j++) 
    {
	prev = &resources[j];
        while ( (this = *prev) )
	{
	    RESTYPE rtype = this->type;
	    if (rtype & RC_NEVERRETAIN)
	    {
		*prev = this->next;
		if (rtype & RC_CACHED)
		    FlushClientCaches(this->id);
		(*DeleteFuncs[rtype & TypeMask])(this->value, this->id);
		xfree(this);	    
	    }
	    else
		prev = &this->next;
	}
    }
}

void
FreeClientResources(client)
    ClientPtr client;
{
    register ResourcePtr *resources;
    register ResourcePtr this;
    int j;

    /* This routine shouldn't be called with a null client, but just in
	case ... */

    if (!client)
	return;

    HandleSaveSet(client);

    resources = clientTable[client->index].resources;
    for (j=0; j < clientTable[client->index].buckets; j++) 
    {
        /* It may seem silly to update the head of this resource list as
	we delete the members, since the entire list will be deleted any way, 
	but there are some resource deletion functions "FreeClientPixels" for 
	one which do a LookupID on another resource id (a Colormap id in this
	case), so the resource list must be kept valid up to the point that
	it is deleted, so every time we delete a resource, we must update the
	head, just like in FreeResource. I hope that this doesn't slow down
	mass deletion appreciably. PRH */

	ResourcePtr *head;

	head = &resources[j];

        for (this = *head; this; this = *head)
	{
	    RESTYPE rtype = this->type;
	    *head = this->next;
	    if (rtype & RC_CACHED)
		FlushClientCaches(this->id);
	    (*DeleteFuncs[rtype & TypeMask])(this->value, this->id);
	    xfree(this);	    
	}
    }
    xfree(clientTable[client->index].resources);
    clientTable[client->index].buckets = 0;
}

void
FreeAllResources()
{
    int	i;

    for (i = currentMaxClients; --i >= 0; ) 
    {
        if (clientTable[i].buckets) 
	    FreeClientResources(clients[i]);
    }
}

Bool
LegalNewID(id, client)
    XID id;
    register ClientPtr client;
{
    return ((client->clientAsMask == (id & ~RESOURCE_ID_MASK)) &&
	    ((clientTable[client->index].expectID <= id) ||
	     !LookupIDByClass(id, RC_ANY)));
}

#ifdef XCSECURITY

/* SecurityLookupIDByType and SecurityLookupIDByClass:
 * These are the heart of the resource ID security system.  They take
 * two additional arguments compared to the old LookupID functions:
 * the client doing the lookup, and the access mode (see resource.h).
 * The resource is returned if it exists and the client is allowed access,
 * else NULL is returned.
 */

pointer
SecurityLookupIDByType(client, id, rtype, mode)
    ClientPtr client;
    XID id;
    RESTYPE rtype;
    Mask mode;
{
    int    cid;
    register    ResourcePtr res;
    pointer retval = NULL;

    assert(client == NullClient ||
     (client->index <= currentMaxClients && clients[client->index] == client));
    assert( (rtype & TypeMask) <= lastResourceType);

    if (((cid = CLIENT_ID(id)) < MAXCLIENTS) &&
	clientTable[cid].buckets)
    {
	res = clientTable[cid].resources[Hash(cid, id)];

	for (; res; res = res->next)
	    if ((res->id == id) && (res->type == rtype))
	    {
		retval = res->value;
		break;
	    }
    }
    if (retval && client && client->CheckAccess)
	retval = (* client->CheckAccess)(client, id, rtype, mode, retval);
    return retval;
}


pointer
SecurityLookupIDByClass(client, id, classes, mode)
    ClientPtr client;
    XID id;
    RESTYPE classes;
    Mask mode;
{
    int    cid;
    register    ResourcePtr res;
    pointer retval = NULL;

    assert(client == NullClient ||
     (client->index <= currentMaxClients && clients[client->index] == client));
    assert (classes >= lastResourceClass);

    if (((cid = CLIENT_ID(id)) < MAXCLIENTS) &&
	clientTable[cid].buckets)
    {
	res = clientTable[cid].resources[Hash(cid, id)];

	for (; res; res = res->next)
	    if ((res->id == id) && (res->type & classes))
	    {
		retval = res->value;
		break;
	    }
    }
    if (retval && client && client->CheckAccess)
	retval = (* client->CheckAccess)(client, id, classes, mode, retval);
    return retval;
}

/* We can't replace the LookupIDByType and LookupIDByClass functions with
 * macros because of compatibility with loadable servers.
 */

pointer
LookupIDByType(id, rtype)
    XID id;
    RESTYPE rtype;
{
    return SecurityLookupIDByType(NullClient, id, rtype,
				  SecurityUnknownAccess);
}

pointer
LookupIDByClass(id, classes)
    XID id;
    RESTYPE classes;
{
    return SecurityLookupIDByClass(NullClient, id, classes,
				   SecurityUnknownAccess);
}

#else /* not XCSECURITY */

/*
 *  LookupIDByType returns the object with the given id and type, else NULL.
 */ 
pointer
LookupIDByType(id, rtype)
    XID id;
    RESTYPE rtype;
{
    int    cid;
    register    ResourcePtr res;

    if (((cid = CLIENT_ID(id)) < MAXCLIENTS) &&
	clientTable[cid].buckets)
    {
	res = clientTable[cid].resources[Hash(cid, id)];

	for (; res; res = res->next)
	    if ((res->id == id) && (res->type == rtype))
		return res->value;
    }
    return (pointer)NULL;
}

/*
 *  LookupIDByClass returns the object with the given id and any one of the
 *  given classes, else NULL.
 */ 
pointer
LookupIDByClass(id, classes)
    XID id;
    RESTYPE classes;
{
    int    cid;
    register    ResourcePtr res;

    if (((cid = CLIENT_ID(id)) < MAXCLIENTS) &&
	clientTable[cid].buckets)
    {
	res = clientTable[cid].resources[Hash(cid, id)];

	for (; res; res = res->next)
	    if ((res->id == id) && (res->type & classes))
		return res->value;
    }
    return (pointer)NULL;
}

#endif /* XCSECURITY */