dlls/mshtml/mutation.c

   1 /*
   2  * Copyright 2008 Jacek Caban for CodeWeavers
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  17  */
  18
  19 #include "config.h"
  20
  21 #include <stdarg.h>
  22
  23 #define COBJMACROS
  24
  25 #include "windef.h"
  26 #include "winbase.h"
  27 #include "winuser.h"
  28 #include "winreg.h"
  29 #include "ole2.h"
  30
  31 #include "mshtml_private.h"
  32 #include "htmlevent.h"
  33
  34 #include "wine/debug.h"
  35
  36 WINE_DEFAULT_DEBUG_CHANNEL(mshtml);
  37
  38 enum {
  39     MUTATION_COMMENT,
  40     MUTATION_SCRIPT
  41 };
  42
  43 void set_mutation_observer(NSContainer *nscontainer, nsIDOMHTMLDocument *nshtmldoc)
  44 {
  45     nsIDOMNSDocument *nsdoc;
  46     nsresult nsres;
  47
  48     nsres = nsIDOMHTMLDocument_QueryInterface(nshtmldoc, &IID_nsIDOMNSDocument, (void**)&nsdoc);
  49     if(NS_FAILED(nsres)) {
  50         ERR("Could not get nsIDOMNSDocument: %08x\n", nsres);
  51         return;
  52     }
  53
  54     nsIDOMNSDocument_WineAddObserver(nsdoc, NSDOCOBS(nscontainer));
  55     nsIDOMNSDocument_Release(nsdoc);
  56 }
  57
  58 void remove_mutation_observer(NSContainer *nscontainer, nsIDOMHTMLDocument *nshtmldoc)
  59 {
  60     nsIDOMNSDocument *nsdoc;
  61     nsresult nsres;
  62
  63     nsres = nsIDOMHTMLDocument_QueryInterface(nshtmldoc, &IID_nsIDOMNSDocument, (void**)&nsdoc);
  64     if(NS_FAILED(nsres)) {
  65         ERR("Could not get nsIDOMNSDocument: %08x\n", nsres);
  66         return;
  67     }
  68
  69     nsIDOMNSDocument_WineRemoveObserver(nsdoc, NSDOCOBS(nscontainer));
  70     nsIDOMNSDocument_Release(nsdoc);
  71 }
  72
  73 #define IE_MAJOR_VERSION 7
  74 #define IE_MINOR_VERSION 0
  75
  76 static BOOL handle_insert_comment(HTMLDocument *doc, const PRUnichar *comment)
  77 {
  78     DWORD len;
  79     int majorv = 0, minorv = 0;
  80     const PRUnichar *ptr, *end;
  81     nsAString nsstr;
  82     PRUnichar *buf;
  83     nsresult nsres;
  84
  85     enum {
  86         CMP_EQ,
  87         CMP_LT,
  88         CMP_LTE,
  89         CMP_GT,
  90         CMP_GTE
  91     } cmpt = CMP_EQ;
  92
  93     static const PRUnichar endifW[] = {'<','!','[','e','n','d','i','f',']'};
  94
  95     if(comment[0] != '[' || comment[1] != 'i' || comment[2] != 'f')
  96         return FALSE;
  97
  98     ptr = comment+3;
  99     while(isspaceW(*ptr))
 100         ptr++;
 101
 102     if(ptr[0] == 'l' && ptr[1] == 't') {
 103         ptr += 2;
 104         if(*ptr == 'e') {
 105             cmpt = CMP_LTE;
 106             ptr++;
 107         }else {
 108             cmpt = CMP_LT;
 109         }
 110     }else if(ptr[0] == 'g' && ptr[1] == 't') {
 111         ptr += 2;
 112         if(*ptr == 'e') {
 113             cmpt = CMP_GTE;
 114             ptr++;
 115         }else {
 116             cmpt = CMP_GT;
 117         }
 118     }
 119
 120     if(!isspaceW(*ptr++))
 121         return FALSE;
 122     while(isspaceW(*ptr))
 123         ptr++;
 124
 125     if(ptr[0] != 'I' || ptr[1] != 'E')
 126         return FALSE;
 127
 128     ptr +=2;
 129     if(!isspaceW(*ptr++))
 130         return FALSE;
 131     while(isspaceW(*ptr))
 132         ptr++;
 133
 134     if(!isdigitW(*ptr))
 135         return FALSE;
 136     while(isdigitW(*ptr))
 137         majorv = majorv*10 + (*ptr++ - '0');
 138
 139     if(*ptr == '.') {
 140         ptr++;
 141         if(!isdigitW(*ptr))
 142             return FALSE;
 143         while(isdigitW(*ptr))
 144             minorv = minorv*10 + (*ptr++ - '0');
 145     }
 146
 147     while(isspaceW(*ptr))
 148         ptr++;
 149     if(ptr[0] != ']' || ptr[1] != '>')
 150         return FALSE;
 151     ptr += 2;
 152
 153     len = strlenW(ptr);
 154     if(len < sizeof(endifW)/sizeof(WCHAR))
 155         return FALSE;
 156
 157     end = ptr + len-sizeof(endifW)/sizeof(WCHAR);
 158     if(memcmp(end, endifW, sizeof(endifW)))
 159         return FALSE;
 160
 161     switch(cmpt) {
 162     case CMP_EQ:
 163         if(majorv == IE_MAJOR_VERSION && minorv == IE_MINOR_VERSION)
 164             break;
 165         return FALSE;
 166     case CMP_LT:
 167         if(majorv > IE_MAJOR_VERSION)
 168             break;
 169         if(majorv == IE_MAJOR_VERSION && minorv > IE_MINOR_VERSION)
 170             break;
 171         return FALSE;
 172     case CMP_LTE:
 173         if(majorv > IE_MAJOR_VERSION)
 174             break;
 175         if(majorv == IE_MAJOR_VERSION && minorv >= IE_MINOR_VERSION)
 176             break;
 177         return FALSE;
 178     case CMP_GT:
 179         if(majorv < IE_MAJOR_VERSION)
 180             break;
 181         if(majorv == IE_MAJOR_VERSION && minorv < IE_MINOR_VERSION)
 182             break;
 183         return FALSE;
 184     case CMP_GTE:
 185         if(majorv < IE_MAJOR_VERSION)
 186             break;
 187         if(majorv == IE_MAJOR_VERSION && minorv <= IE_MINOR_VERSION)
 188             break;
 189         return FALSE;
 190     }
 191
 192     buf = heap_alloc((end-ptr+1)*sizeof(WCHAR));
 193     if(!buf)
 194         return FALSE;
 195
 196     memcpy(buf, ptr, (end-ptr)*sizeof(WCHAR));
 197     buf[end-ptr] = 0;
 198     nsAString_Init(&nsstr, buf);
 199     heap_free(buf);
 200
 201     /* FIXME: Find better way to insert HTML to document. */
 202     nsres = nsIDOMHTMLDocument_Write(doc->nsdoc, &nsstr);
 203     nsAString_Finish(&nsstr);
 204     if(NS_FAILED(nsres)) {
 205         ERR("Write failed: %08x\n", nsres);
 206         return FALSE;
 207     }
 208
 209     return TRUE;
 210 }
 211
 212 static void add_script_runner(NSContainer *This)
 213 {
 214     nsIDOMNSDocument *nsdoc;
 215     nsresult nsres;
 216
 217     nsres = nsIDOMHTMLDocument_QueryInterface(This->doc->nsdoc, &IID_nsIDOMNSDocument, (void**)&nsdoc);
 218     if(NS_FAILED(nsres)) {
 219         ERR("Could not get nsIDOMNSDocument: %08x\n", nsres);
 220         return;
 221     }
 222
 223     nsIDOMNSDocument_WineAddScriptRunner(nsdoc, NSRUNNABLE(This));
 224     nsIDOMNSDocument_Release(nsdoc);
 225 }
 226
 227 #define NSRUNNABLE_THIS(iface) DEFINE_THIS(NSContainer, Runnable, iface)
 228
 229 static nsresult NSAPI nsRunnable_QueryInterface(nsIRunnable *iface,
 230         nsIIDRef riid, nsQIResult result)
 231 {
 232     NSContainer *This = NSRUNNABLE_THIS(iface);
 233
 234     if(IsEqualGUID(riid, &IID_nsISupports)) {
 235         TRACE("(%p)->(IID_nsISupports %p)\n", This, result);
 236         *result = NSRUNNABLE(This);
 237     }else if(IsEqualGUID(riid, &IID_nsIRunnable)) {
 238         TRACE("(%p)->(IID_nsIRunnable %p)\n", This, result);
 239         *result = NSRUNNABLE(This);
 240     }else {
 241         *result = NULL;
 242         WARN("(%p)->(%s %p)\n", This, debugstr_guid(riid), result);
 243         return NS_NOINTERFACE;
 244     }
 245
 246     nsISupports_AddRef((nsISupports*)*result);
 247     return NS_OK;
 248 }
 249
 250 static nsrefcnt NSAPI nsRunnable_AddRef(nsIRunnable *iface)
 251 {
 252     NSContainer *This = NSRUNNABLE_THIS(iface);
 253     return nsIWebBrowserChrome_AddRef(NSWBCHROME(This));
 254 }
 255
 256 static nsrefcnt NSAPI nsRunnable_Release(nsIRunnable *iface)
 257 {
 258     NSContainer *This = NSRUNNABLE_THIS(iface);
 259     return nsIWebBrowserChrome_Release(NSWBCHROME(This));
 260 }
 261
 262 static void pop_mutation_queue(NSContainer *nscontainer)
 263 {
 264     mutation_queue_t *tmp = nscontainer->mutation_queue;
 265
 266     if(!tmp)
 267         return;
 268
 269     nscontainer->mutation_queue = tmp->next;
 270     if(!tmp->next)
 271         nscontainer->mutation_queue_tail = NULL;
 272
 273     nsISupports_Release(tmp->nsiface);
 274     heap_free(tmp);
 275 }
 276
 277 static nsresult NSAPI nsRunnable_Run(nsIRunnable *iface)
 278 {
 279     NSContainer *This = NSRUNNABLE_THIS(iface);
 280     nsresult nsres;
 281
 282     TRACE("(%p)\n", This);
 283
 284     while(This->mutation_queue) {
 285         switch(This->mutation_queue->type) {
 286         case MUTATION_COMMENT: {
 287             nsIDOMComment *nscomment;
 288             nsAString comment_str;
 289             BOOL remove_comment = FALSE;
 290
 291             nsres = nsISupports_QueryInterface(This->mutation_queue->nsiface, &IID_nsIDOMComment, (void**)&nscomment);
 292             if(NS_FAILED(nsres)) {
 293                 ERR("Could not get nsIDOMComment iface:%08x\n", nsres);
 294                 return NS_OK;
 295             }
 296
 297             nsAString_Init(&comment_str, NULL);
 298             nsres = nsIDOMComment_GetData(nscomment, &comment_str);
 299             if(NS_SUCCEEDED(nsres)) {
 300                 const PRUnichar *comment;
 301
 302                 nsAString_GetData(&comment_str, &comment);
 303                 remove_comment = handle_insert_comment(This->doc, comment);
 304             }
 305
 306             nsAString_Finish(&comment_str);
 307
 308             if(remove_comment) {
 309                 nsIDOMNode *nsparent, *tmp;
 310                 nsAString magic_str;
 311
 312                 static const PRUnichar remove_comment_magicW[] =
 313                     {'#','!','w','i','n','e', 'r','e','m','o','v','e','!','#',0};
 314
 315                 nsAString_Init(&magic_str, remove_comment_magicW);
 316                 nsres = nsIDOMComment_SetData(nscomment, &magic_str);
 317                 nsAString_Finish(&magic_str);
 318                 if(NS_FAILED(nsres))
 319                     ERR("SetData failed: %08x\n", nsres);
 320
 321                 nsIDOMComment_GetParentNode(nscomment, &nsparent);
 322                 if(nsparent) {
 323                     nsIDOMNode_RemoveChild(nsparent, (nsIDOMNode*)nscomment, &tmp);
 324                     nsIDOMNode_Release(nsparent);
 325                     nsIDOMNode_Release(tmp);
 326                 }
 327             }
 328
 329             nsIDOMComment_Release(nscomment);
 330             break;
 331         }
 332
 333         case MUTATION_SCRIPT: {
 334             nsIDOMHTMLScriptElement *nsscript;
 335
 336             nsres = nsISupports_QueryInterface(This->mutation_queue->nsiface, &IID_nsIDOMHTMLScriptElement,
 337                                                (void**)&nsscript);
 338             if(NS_FAILED(nsres)) {
 339                 ERR("Could not get nsIDOMHTMLScriptElement: %08x\n", nsres);
 340                 break;
 341             }
 342
 343             doc_insert_script(This->doc, nsscript);
 344             nsIDOMHTMLScriptElement_Release(nsscript);
 345             break;
 346         }
 347
 348         default:
 349             ERR("invalid type %d\n", This->mutation_queue->type);
 350         }
 351
 352         pop_mutation_queue(This);
 353     }
 354
 355     return S_OK;
 356 }
 357
 358 #undef NSRUNNABLE_THIS
 359
 360 static const nsIRunnableVtbl nsRunnableVtbl = {
 361     nsRunnable_QueryInterface,
 362     nsRunnable_AddRef,
 363     nsRunnable_Release,
 364     nsRunnable_Run
 365 };
 366
 367 #define NSDOCOBS_THIS(iface) DEFINE_THIS(NSContainer, DocumentObserver, iface)
 368
 369 static nsresult NSAPI nsDocumentObserver_QueryInterface(nsIDocumentObserver *iface,
 370         nsIIDRef riid, nsQIResult result)
 371 {
 372     NSContainer *This = NSDOCOBS_THIS(iface);
 373
 374     if(IsEqualGUID(&IID_nsISupports, riid)) {
 375         TRACE("(%p)->(IID_nsISupports, %p)\n", This, result);
 376         *result = NSDOCOBS(This);
 377     }else if(IsEqualGUID(&IID_nsIMutationObserver, riid)) {
 378         TRACE("(%p)->(IID_nsIMutationObserver %p)\n", This, result);
 379         *result = NSDOCOBS(This);
 380     }else if(IsEqualGUID(&IID_nsIDocumentObserver, riid)) {
 381         TRACE("(%p)->(IID_nsIDocumentObserver %p)\n", This, result);
 382         *result = NSDOCOBS(This);
 383     }else {
 384         *result = NULL;
 385         TRACE("(%p)->(%s %p)\n", This, debugstr_guid(riid), result);
 386         return NS_NOINTERFACE;
 387     }
 388
 389     nsIWebBrowserChrome_AddRef(NSWBCHROME(This));
 390     return NS_OK;
 391 }
 392
 393 static nsrefcnt NSAPI nsDocumentObserver_AddRef(nsIDocumentObserver *iface)
 394 {
 395     NSContainer *This = NSDOCOBS_THIS(iface);
 396     return nsIWebBrowserChrome_AddRef(NSWBCHROME(This));
 397 }
 398
 399 static nsrefcnt NSAPI nsDocumentObserver_Release(nsIDocumentObserver *iface)
 400 {
 401     NSContainer *This = NSDOCOBS_THIS(iface);
 402     return nsIWebBrowserChrome_Release(NSWBCHROME(This));
 403 }
 404
 405 static void NSAPI nsDocumentObserver_CharacterDataWillChange(nsIDocumentObserver *iface,
 406         nsIDocument *aDocument, nsIContent *aContent, void /*CharacterDataChangeInfo*/ *aInfo)
 407 {
 408 }
 409
 410 static void NSAPI nsDocumentObserver_CharacterDataChanged(nsIDocumentObserver *iface,
 411         nsIDocument *aDocument, nsIContent *aContent, void /*CharacterDataChangeInfo*/ *aInfo)
 412 {
 413 }
 414
 415 static void NSAPI nsDocumentObserver_AttributeChanged(nsIDocumentObserver *iface, nsIDocument *aDocument,
 416         nsIContent *aContent, PRInt32 aNameSpaceID, nsIAtom *aAttribute, PRInt32 aModType, PRUint32 aStateMask)
 417 {
 418 }
 419
 420 static void NSAPI nsDocumentObserver_ContentAppended(nsIDocumentObserver *iface, nsIDocument *aDocument,
 421         nsIContent *aContainer, PRInt32 aNewIndexInContainer)
 422 {
 423 }
 424
 425 static void NSAPI nsDocumentObserver_ContentInserted(nsIDocumentObserver *iface, nsIDocument *aDocument,
 426         nsIContent *aContainer, nsIContent *aChild, PRInt32 aIndexInContainer)
 427 {
 428 }
 429
 430 static void NSAPI nsDocumentObserver_ContentRemoved(nsIDocumentObserver *iface, nsIDocument *aDocument,
 431         nsIContent *aContainer, nsIContent *aChild, PRInt32 aIndexInContainer)
 432 {
 433 }
 434
 435 static void NSAPI nsDocumentObserver_NodeWillBeDestroyed(nsIDocumentObserver *iface, const nsINode *aNode)
 436 {
 437 }
 438
 439 static void NSAPI nsDocumentObserver_ParentChainChanged(nsIDocumentObserver *iface, nsIContent *aContent)
 440 {
 441 }
 442
 443 static void NSAPI nsDocumentObserver_BeginUpdate(nsIDocumentObserver *iface, nsIDocument *aDocument,
 444         nsUpdateType aUpdateType)
 445 {
 446 }
 447
 448 static void NSAPI nsDocumentObserver_EndUpdate(nsIDocumentObserver *iface, nsIDocument *aDocument,
 449         nsUpdateType aUpdateType)
 450 {
 451 }
 452
 453 static void NSAPI nsDocumentObserver_BeginLoad(nsIDocumentObserver *iface, nsIDocument *aDocument)
 454 {
 455 }
 456
 457 static void NSAPI nsDocumentObserver_EndLoad(nsIDocumentObserver *iface, nsIDocument *aDocument)
 458 {
 459 }
 460
 461 static void NSAPI nsDocumentObserver_ContentStatesChanged(nsIDocumentObserver *iface, nsIDocument *aDocument,
 462         nsIContent *aContent1, nsIContent *aContent2, PRInt32 aStateMask)
 463 {
 464 }
 465
 466 static void NSAPI nsDocumentObserver_StyleSheetAdded(nsIDocumentObserver *iface, nsIDocument *aDocument,
 467         nsIStyleSheet *aStyleSheet, PRBool aDocumentSheet)
 468 {
 469 }
 470
 471 static void NSAPI nsDocumentObserver_StyleSheetRemoved(nsIDocumentObserver *iface, nsIDocument *aDocument,
 472         nsIStyleSheet *aStyleSheet, PRBool aDocumentSheet)
 473 {
 474 }
 475
 476 static void NSAPI nsDocumentObserver_StyleSheetApplicableStateChanged(nsIDocumentObserver *iface,
 477         nsIDocument *aDocument, nsIStyleSheet *aStyleSheet, PRBool aApplicable)
 478 {
 479 }
 480
 481 static void NSAPI nsDocumentObserver_StyleRuleChanged(nsIDocumentObserver *iface, nsIDocument *aDocument,
 482         nsIStyleSheet *aStyleSheet, nsIStyleRule *aOldStyleRule, nsIStyleSheet *aNewStyleRule)
 483 {
 484 }
 485
 486 static void NSAPI nsDocumentObserver_StyleRuleAdded(nsIDocumentObserver *iface, nsIDocument *aDocument,
 487         nsIStyleSheet *aStyleSheet, nsIStyleRule *aStyleRule)
 488 {
 489 }
 490
 491 static void NSAPI nsDocumentObserver_StyleRuleRemoved(nsIDocumentObserver *iface, nsIDocument *aDocument,
 492         nsIStyleSheet *aStyleSheet, nsIStyleRule *aStyleRule)
 493 {
 494 }
 495
 496 static void push_mutation_queue(NSContainer *nscontainer, DWORD type, nsISupports *nsiface)
 497 {
 498     mutation_queue_t *elem;
 499
 500     elem = heap_alloc(sizeof(mutation_queue_t));
 501     if(!elem)
 502         return;
 503
 504     elem->next = NULL;
 505     elem->type = type;
 506     elem->nsiface = nsiface;
 507     nsISupports_AddRef(nsiface);
 508
 509     if(nscontainer->mutation_queue_tail)
 510         nscontainer->mutation_queue_tail = nscontainer->mutation_queue_tail->next = elem;
 511     else
 512         nscontainer->mutation_queue = nscontainer->mutation_queue_tail = elem;
 513 }
 514
 515 static void NSAPI nsDocumentObserver_BindToDocument(nsIDocumentObserver *iface, nsIDocument *aDocument,
 516         nsIContent *aContent)
 517 {
 518     NSContainer *This = NSDOCOBS_THIS(iface);
 519     nsIDOMComment *nscomment;
 520     nsIDOMElement *nselem;
 521     nsresult nsres;
 522
 523     TRACE("(%p)\n", This);
 524
 525     nsres = nsISupports_QueryInterface(aContent, &IID_nsIDOMElement, (void**)&nselem);
 526     if(NS_SUCCEEDED(nsres)) {
 527         check_event_attr(This->doc, nselem);
 528         nsIDOMElement_Release(nselem);
 529     }
 530
 531     nsres = nsISupports_QueryInterface(aContent, &IID_nsIDOMComment, (void**)&nscomment);
 532     if(NS_SUCCEEDED(nsres)) {
 533         TRACE("comment node\n");
 534
 535         push_mutation_queue(This, MUTATION_COMMENT, (nsISupports*)nscomment);
 536         nsIDOMComment_Release(nscomment);
 537         add_script_runner(This);
 538     }
 539 }
 540
 541 static void NSAPI nsDocumentObserver_DoneAddingChildren(nsIDocumentObserver *iface, nsIContent *aContent,
 542         PRBool aHaveNotified)
 543 {
 544     NSContainer *This = NSDOCOBS_THIS(iface);
 545     nsIDOMHTMLScriptElement *nsscript;
 546     nsresult nsres;
 547
 548     TRACE("(%p)->(%p %x)\n", This, aContent, aHaveNotified);
 549
 550     nsres = nsISupports_QueryInterface(aContent, &IID_nsIDOMHTMLScriptElement, (void**)&nsscript);
 551     if(NS_SUCCEEDED(nsres)) {
 552         push_mutation_queue(This, MUTATION_SCRIPT, (nsISupports*)nsscript);
 553         nsIDOMHTMLScriptElement_Release(nsscript);
 554         add_script_runner(This);
 555     }
 556 }
 557
 558 #undef NSMUTATIONOBS_THIS
 559
 560 static const nsIDocumentObserverVtbl nsDocumentObserverVtbl = {
 561     nsDocumentObserver_QueryInterface,
 562     nsDocumentObserver_AddRef,
 563     nsDocumentObserver_Release,
 564     nsDocumentObserver_CharacterDataWillChange,
 565     nsDocumentObserver_CharacterDataChanged,
 566     nsDocumentObserver_AttributeChanged,
 567     nsDocumentObserver_ContentAppended,
 568     nsDocumentObserver_ContentInserted,
 569     nsDocumentObserver_ContentRemoved,
 570     nsDocumentObserver_NodeWillBeDestroyed,
 571     nsDocumentObserver_ParentChainChanged,
 572     nsDocumentObserver_BeginUpdate,
 573     nsDocumentObserver_EndUpdate,
 574     nsDocumentObserver_BeginLoad,
 575     nsDocumentObserver_EndLoad,
 576     nsDocumentObserver_ContentStatesChanged,
 577     nsDocumentObserver_StyleSheetAdded,
 578     nsDocumentObserver_StyleSheetRemoved,
 579     nsDocumentObserver_StyleSheetApplicableStateChanged,
 580     nsDocumentObserver_StyleRuleChanged,
 581     nsDocumentObserver_StyleRuleAdded,
 582     nsDocumentObserver_StyleRuleRemoved,
 583     nsDocumentObserver_BindToDocument,
 584     nsDocumentObserver_DoneAddingChildren
 585 };
 586
 587 void init_mutation(NSContainer *nscontainer)
 588 {
 589     nscontainer->lpDocumentObserverVtbl  = &nsDocumentObserverVtbl;
 590     nscontainer->lpRunnableVtbl          = &nsRunnableVtbl;
 591 }