dlls/ntdll/exception.c

   1 /*
   2  * NT exception handling routines
   3  *
   4  * Copyright 1999 Turchanov Sergey
   5  * Copyright 1999 Alexandre Julliard
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  20  */
  21
  22 #include "config.h"
  23 #include "wine/port.h"
  24
  25 #include <assert.h>
  26 #include <errno.h>
  27 #include <signal.h>
  28 #include <stdarg.h>
  29
  30 #include "ntstatus.h"
  31 #define WIN32_NO_STATUS
  32 #include "windef.h"
  33 #include "winternl.h"
  34 #include "wine/exception.h"
  35 #include "wine/server.h"
  36 #include "wine/list.h"
  37 #include "wine/debug.h"
  38 #include "excpt.h"
  39 #include "ntdll_misc.h"
  40
  41 WINE_DEFAULT_DEBUG_CHANNEL(seh);
  42
  43 /* Exception record for handling exceptions happening inside exception handlers */
  44 typedef struct
  45 {
  46     EXCEPTION_REGISTRATION_RECORD frame;
  47     EXCEPTION_REGISTRATION_RECORD *prevFrame;
  48 } EXC_NESTED_FRAME;
  49
  50 typedef struct
  51 {
  52     struct list                 entry;
  53     PVECTORED_EXCEPTION_HANDLER func;
  54 } VECTORED_HANDLER;
  55
  56 static struct list vectored_handlers = LIST_INIT(vectored_handlers);
  57
  58 static RTL_CRITICAL_SECTION vectored_handlers_section;
  59 static RTL_CRITICAL_SECTION_DEBUG critsect_debug =
  60 {
  61     0, 0, &vectored_handlers_section,
  62     { &critsect_debug.ProcessLocksList, &critsect_debug.ProcessLocksList },
  63       0, 0, { (DWORD_PTR)(__FILE__ ": vectored_handlers_section") }
  64 };
  65 static RTL_CRITICAL_SECTION vectored_handlers_section = { &critsect_debug, -1, 0, 0, 0, 0 };
  66
  67 #ifdef __i386__
  68 # define GET_IP(context) ((LPVOID)(context)->Eip)
  69 #elif defined(__sparc__)
  70 # define GET_IP(context) ((LPVOID)(context)->pc)
  71 #elif defined(__powerpc__)
  72 # define GET_IP(context) ((LPVOID)(context)->Iar)
  73 #elif defined(__ALPHA__)
  74 # define GET_IP(context) ((LPVOID)(context)->Fir)
  75 #elif defined(__x86_64__)
  76 # define GET_IP(context) ((LPVOID)(context)->Rip)
  77 #else
  78 # error You must define GET_IP for this CPU
  79 #endif
  80
  81 /*******************************************************************
  82  *         EXC_RaiseHandler
  83  *
  84  * Handler for exceptions happening inside a handler.
  85  */
  86 static DWORD EXC_RaiseHandler( EXCEPTION_RECORD *rec, EXCEPTION_REGISTRATION_RECORD *frame,
  87                                CONTEXT *context, EXCEPTION_REGISTRATION_RECORD **dispatcher )
  88 {
  89     if (rec->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND))
  90         return ExceptionContinueSearch;
  91     /* We shouldn't get here so we store faulty frame in dispatcher */
  92     *dispatcher = ((EXC_NESTED_FRAME*)frame)->prevFrame;
  93     return ExceptionNestedException;
  94 }
  95
  96
  97 /*******************************************************************
  98  *         EXC_UnwindHandler
  99  *
 100  * Handler for exceptions happening inside an unwind handler.
 101  */
 102 static DWORD EXC_UnwindHandler( EXCEPTION_RECORD *rec, EXCEPTION_REGISTRATION_RECORD *frame,
 103                                 CONTEXT *context, EXCEPTION_REGISTRATION_RECORD **dispatcher )
 104 {
 105     if (!(rec->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND)))
 106         return ExceptionContinueSearch;
 107     /* We shouldn't get here so we store faulty frame in dispatcher */
 108     *dispatcher = ((EXC_NESTED_FRAME*)frame)->prevFrame;
 109     return ExceptionCollidedUnwind;
 110 }
 111
 112
 113 /*******************************************************************
 114  *         EXC_CallHandler
 115  *
 116  * Call an exception handler, setting up an exception frame to catch exceptions
 117  * happening during the handler execution.
 118  *
 119  * For i386 this function is implemented in assembler in signal_i386.c.
 120  */
 121 #ifndef __i386__
 122 static DWORD EXC_CallHandler( EXCEPTION_RECORD *record, EXCEPTION_REGISTRATION_RECORD *frame,
 123                               CONTEXT *context, EXCEPTION_REGISTRATION_RECORD **dispatcher,
 124                               PEXCEPTION_HANDLER handler, PEXCEPTION_HANDLER nested_handler)
 125 {
 126     EXC_NESTED_FRAME newframe;
 127     DWORD ret;
 128
 129     newframe.frame.Handler = nested_handler;
 130     newframe.prevFrame     = frame;
 131     __wine_push_frame( &newframe.frame );
 132     ret = handler( record, frame, context, dispatcher );
 133     __wine_pop_frame( &newframe.frame );
 134     return ret;
 135 }
 136 #else
 137 /* in signal_i386.c */
 138 extern DWORD EXC_CallHandler( EXCEPTION_RECORD *record, EXCEPTION_REGISTRATION_RECORD *frame,
 139                               CONTEXT *context, EXCEPTION_REGISTRATION_RECORD **dispatcher,
 140                               PEXCEPTION_HANDLER handler, PEXCEPTION_HANDLER nested_handler);
 141 #endif
 142
 143 /**********************************************************************
 144  *           wait_suspend
 145  *
 146  * Wait until the thread is no longer suspended.
 147  */
 148 void wait_suspend( CONTEXT *context )
 149 {
 150     LARGE_INTEGER timeout;
 151     int saved_errno = errno;
 152
 153     /* store the context we got at suspend time */
 154     SERVER_START_REQ( set_thread_context )
 155     {
 156         req->handle  = GetCurrentThread();
 157         req->flags   = CONTEXT_FULL;
 158         req->suspend = 1;
 159         wine_server_add_data( req, context, sizeof(*context) );
 160         wine_server_call( req );
 161     }
 162     SERVER_END_REQ;
 163
 164     /* wait with 0 timeout, will only return once the thread is no longer suspended */
 165     timeout.QuadPart = 0;
 166     NTDLL_wait_for_multiple_objects( 0, NULL, SELECT_INTERRUPTIBLE, &timeout, 0 );
 167
 168     /* retrieve the new context */
 169     SERVER_START_REQ( get_thread_context )
 170     {
 171         req->handle  = GetCurrentThread();
 172         req->flags   = CONTEXT_FULL;
 173         req->suspend = 1;
 174         wine_server_set_reply( req, context, sizeof(*context) );
 175         wine_server_call( req );
 176     }
 177     SERVER_END_REQ;
 178
 179     errno = saved_errno;
 180 }
 181
 182
 183 /**********************************************************************
 184  *           send_debug_event
 185  *
 186  * Send an EXCEPTION_DEBUG_EVENT event to the debugger.
 187  */
 188 static NTSTATUS send_debug_event( EXCEPTION_RECORD *rec, int first_chance, CONTEXT *context )
 189 {
 190     int ret;
 191     HANDLE handle = 0;
 192
 193     if (!NtCurrentTeb()->Peb->BeingDebugged) return 0;  /* no debugger present */
 194
 195     SERVER_START_REQ( queue_exception_event )
 196     {
 197         req->first   = first_chance;
 198         wine_server_add_data( req, context, sizeof(*context) );
 199         wine_server_add_data( req, rec, sizeof(*rec) );
 200         if (!wine_server_call( req )) handle = reply->handle;
 201     }
 202     SERVER_END_REQ;
 203     if (!handle) return 0;
 204
 205     NTDLL_wait_for_multiple_objects( 1, &handle, SELECT_INTERRUPTIBLE, NULL, 0 );
 206
 207     SERVER_START_REQ( get_exception_status )
 208     {
 209         req->handle = handle;
 210         wine_server_set_reply( req, context, sizeof(*context) );
 211         ret = wine_server_call( req );
 212     }
 213     SERVER_END_REQ;
 214     return ret;
 215 }
 216
 217
 218 /**********************************************************************
 219  *           call_vectored_handlers
 220  *
 221  * Call the vectored handlers chain.
 222  */
 223 static LONG call_vectored_handlers( EXCEPTION_RECORD *rec, CONTEXT *context )
 224 {
 225     struct list *ptr;
 226     LONG ret = EXCEPTION_CONTINUE_SEARCH;
 227     EXCEPTION_POINTERS except_ptrs;
 228
 229     except_ptrs.ExceptionRecord = rec;
 230     except_ptrs.ContextRecord = context;
 231
 232     RtlEnterCriticalSection( &vectored_handlers_section );
 233     LIST_FOR_EACH( ptr, &vectored_handlers )
 234     {
 235         VECTORED_HANDLER *handler = LIST_ENTRY( ptr, VECTORED_HANDLER, entry );
 236         ret = handler->func( &except_ptrs );
 237         if (ret == EXCEPTION_CONTINUE_EXECUTION) break;
 238     }
 239     RtlLeaveCriticalSection( &vectored_handlers_section );
 240     return ret;
 241 }
 242
 243
 244 /**********************************************************************
 245  *           call_stack_handlers
 246  *
 247  * Call the stack handlers chain.
 248  */
 249 static NTSTATUS call_stack_handlers( EXCEPTION_RECORD *rec, CONTEXT *context )
 250 {
 251     EXCEPTION_REGISTRATION_RECORD *frame, *dispatch, *nested_frame;
 252     DWORD res;
 253
 254     frame = NtCurrentTeb()->Tib.ExceptionList;
 255     nested_frame = NULL;
 256     while (frame != (EXCEPTION_REGISTRATION_RECORD*)~0UL)
 257     {
 258         /* Check frame address */
 259         if (((void*)frame < NtCurrentTeb()->Tib.StackLimit) ||
 260             ((void*)(frame+1) > NtCurrentTeb()->Tib.StackBase) ||
 261             (ULONG_PTR)frame & 3)
 262         {
 263             rec->ExceptionFlags |= EH_STACK_INVALID;
 264             break;
 265         }
 266
 267         /* Call handler */
 268         TRACE( "calling handler at %p code=%x flags=%x\n",
 269                frame->Handler, rec->ExceptionCode, rec->ExceptionFlags );
 270         res = EXC_CallHandler( rec, frame, context, &dispatch, frame->Handler, EXC_RaiseHandler );
 271         TRACE( "handler at %p returned %x\n", frame->Handler, res );
 272
 273         if (frame == nested_frame)
 274         {
 275             /* no longer nested */
 276             nested_frame = NULL;
 277             rec->ExceptionFlags &= ~EH_NESTED_CALL;
 278         }
 279
 280         switch(res)
 281         {
 282         case ExceptionContinueExecution:
 283             if (!(rec->ExceptionFlags & EH_NONCONTINUABLE)) return STATUS_SUCCESS;
 284             return STATUS_NONCONTINUABLE_EXCEPTION;
 285         case ExceptionContinueSearch:
 286             break;
 287         case ExceptionNestedException:
 288             if (nested_frame < dispatch) nested_frame = dispatch;
 289             rec->ExceptionFlags |= EH_NESTED_CALL;
 290             break;
 291         default:
 292             return STATUS_INVALID_DISPOSITION;
 293         }
 294         frame = frame->Prev;
 295     }
 296     return STATUS_UNHANDLED_EXCEPTION;
 297 }
 298
 299
 300 /*******************************************************************
 301  *              raise_exception
 302  *
 303  * Implementation of NtRaiseException.
 304  */
 305 static NTSTATUS raise_exception( EXCEPTION_RECORD *rec, CONTEXT *context, BOOL first_chance )
 306 {
 307     NTSTATUS status;
 308
 309     if (first_chance)
 310     {
 311         DWORD c;
 312
 313         TRACE( "code=%x flags=%x addr=%p\n",
 314                rec->ExceptionCode, rec->ExceptionFlags, rec->ExceptionAddress );
 315         for (c = 0; c < rec->NumberParameters; c++)
 316             TRACE( " info[%d]=%08lx\n", c, rec->ExceptionInformation[c] );
 317         if (rec->ExceptionCode == EXCEPTION_WINE_STUB)
 318         {
 319             if (rec->ExceptionInformation[1] >> 16)
 320                 MESSAGE( "wine: Call from %p to unimplemented function %s.%s, aborting\n",
 321                          rec->ExceptionAddress,
 322                          (char*)rec->ExceptionInformation[0], (char*)rec->ExceptionInformation[1] );
 323             else
 324                 MESSAGE( "wine: Call from %p to unimplemented function %s.%ld, aborting\n",
 325                          rec->ExceptionAddress,
 326                          (char*)rec->ExceptionInformation[0], rec->ExceptionInformation[1] );
 327         }
 328 #ifdef __i386__
 329         else
 330         {
 331             TRACE(" eax=%08x ebx=%08x ecx=%08x edx=%08x esi=%08x edi=%08x\n",
 332                   context->Eax, context->Ebx, context->Ecx,
 333                   context->Edx, context->Esi, context->Edi );
 334             TRACE(" ebp=%08x esp=%08x cs=%04x ds=%04x es=%04x fs=%04x gs=%04x flags=%08x\n",
 335                   context->Ebp, context->Esp, context->SegCs, context->SegDs,
 336                   context->SegEs, context->SegFs, context->SegGs, context->EFlags );
 337         }
 338 #endif
 339         status = send_debug_event( rec, TRUE, context );
 340         if (status == DBG_CONTINUE || status == DBG_EXCEPTION_HANDLED)
 341             return STATUS_SUCCESS;
 342
 343 #ifdef __i386__
 344         /* fix up instruction pointer in context for EXCEPTION_BREAKPOINT */
 345         if (rec->ExceptionCode == EXCEPTION_BREAKPOINT) context->Eip--;
 346 #endif
 347
 348         if (call_vectored_handlers( rec, context ) == EXCEPTION_CONTINUE_EXECUTION)
 349             return STATUS_SUCCESS;
 350
 351         if ((status = call_stack_handlers( rec, context )) != STATUS_UNHANDLED_EXCEPTION)
 352             return status;
 353     }
 354
 355     /* last chance exception */
 356
 357     status = send_debug_event( rec, FALSE, context );
 358     if (status != DBG_CONTINUE)
 359     {
 360         if (rec->ExceptionFlags & EH_STACK_INVALID)
 361             ERR("Exception frame is not in stack limits => unable to dispatch exception.\n");
 362         else if (rec->ExceptionCode == STATUS_NONCONTINUABLE_EXCEPTION)
 363             ERR("Process attempted to continue execution after noncontinuable exception.\n");
 364         else
 365             ERR("Unhandled exception code %x flags %x addr %p\n",
 366                 rec->ExceptionCode, rec->ExceptionFlags, rec->ExceptionAddress );
 367         NtTerminateProcess( NtCurrentProcess(), 1 );
 368     }
 369     return STATUS_SUCCESS;
 370 }
 371
 372
 373 /*******************************************************************
 374  *              NtRaiseException (NTDLL.@)
 375  */
 376 NTSTATUS WINAPI NtRaiseException( EXCEPTION_RECORD *rec, CONTEXT *context, BOOL first_chance )
 377 {
 378     NTSTATUS status = raise_exception( rec, context, first_chance );
 379     if (status == STATUS_SUCCESS) NtSetContextThread( GetCurrentThread(), context );
 380     return status;
 381 }
 382
 383 /***********************************************************************
 384  *              RtlRaiseException (NTDLL.@)
 385  */
 386 void WINAPI __regs_RtlRaiseException( EXCEPTION_RECORD *rec, CONTEXT *context )
 387 {
 388     NTSTATUS status = raise_exception( rec, context, TRUE );
 389     if (status != STATUS_SUCCESS)
 390     {
 391         EXCEPTION_RECORD newrec;
 392         newrec.ExceptionCode    = status;
 393         newrec.ExceptionFlags   = EH_NONCONTINUABLE;
 394         newrec.ExceptionRecord  = rec;
 395         newrec.NumberParameters = 0;
 396         RtlRaiseException( &newrec );  /* never returns */
 397     }
 398 }
 399
 400 /**********************************************************************/
 401
 402 #ifdef DEFINE_REGS_ENTRYPOINT
 403 DEFINE_REGS_ENTRYPOINT( RtlRaiseException, 4, 4 )
 404 #else
 405 void WINAPI RtlRaiseException( EXCEPTION_RECORD *rec )
 406 {
 407     CONTEXT context;
 408     memset( &context, 0, sizeof(context) );
 409     __regs_RtlRaiseException( rec, &context );
 410 }
 411 #endif
 412
 413
 414 /*******************************************************************
 415  *              RtlUnwind (NTDLL.@)
 416  */
 417 void WINAPI __regs_RtlUnwind( EXCEPTION_REGISTRATION_RECORD* pEndFrame, PVOID unusedEip,
 418                               PEXCEPTION_RECORD pRecord, PVOID returnEax, CONTEXT *context )
 419 {
 420     EXCEPTION_RECORD record, newrec;
 421     EXCEPTION_REGISTRATION_RECORD *frame, *dispatch;
 422     DWORD res;
 423
 424 #ifdef __i386__
 425     context->Eax = (DWORD)returnEax;
 426 #endif
 427
 428     /* build an exception record, if we do not have one */
 429     if (!pRecord)
 430     {
 431         record.ExceptionCode    = STATUS_UNWIND;
 432         record.ExceptionFlags   = 0;
 433         record.ExceptionRecord  = NULL;
 434         record.ExceptionAddress = GET_IP(context);
 435         record.NumberParameters = 0;
 436         pRecord = &record;
 437     }
 438
 439     pRecord->ExceptionFlags |= EH_UNWINDING | (pEndFrame ? 0 : EH_EXIT_UNWIND);
 440
 441     TRACE( "code=%x flags=%x\n", pRecord->ExceptionCode, pRecord->ExceptionFlags );
 442
 443     /* get chain of exception frames */
 444     frame = NtCurrentTeb()->Tib.ExceptionList;
 445     while ((frame != (EXCEPTION_REGISTRATION_RECORD*)~0UL) && (frame != pEndFrame))
 446     {
 447         /* Check frame address */
 448         if (pEndFrame && (frame > pEndFrame))
 449         {
 450             newrec.ExceptionCode    = STATUS_INVALID_UNWIND_TARGET;
 451             newrec.ExceptionFlags   = EH_NONCONTINUABLE;
 452             newrec.ExceptionRecord  = pRecord;
 453             newrec.NumberParameters = 0;
 454             RtlRaiseException( &newrec );  /* never returns */
 455         }
 456         if (((void*)frame < NtCurrentTeb()->Tib.StackLimit) ||
 457             ((void*)(frame+1) > NtCurrentTeb()->Tib.StackBase) ||
 458             (UINT_PTR)frame & 3)
 459         {
 460             newrec.ExceptionCode    = STATUS_BAD_STACK;
 461             newrec.ExceptionFlags   = EH_NONCONTINUABLE;
 462             newrec.ExceptionRecord  = pRecord;
 463             newrec.NumberParameters = 0;
 464             RtlRaiseException( &newrec );  /* never returns */
 465         }
 466
 467         /* Call handler */
 468         TRACE( "calling handler at %p code=%x flags=%x\n",
 469                frame->Handler, pRecord->ExceptionCode, pRecord->ExceptionFlags );
 470         res = EXC_CallHandler( pRecord, frame, context, &dispatch, frame->Handler, EXC_UnwindHandler );
 471         TRACE( "handler at %p returned %x\n", frame->Handler, res );
 472
 473         switch(res)
 474         {
 475         case ExceptionContinueSearch:
 476             break;
 477         case ExceptionCollidedUnwind:
 478             frame = dispatch;
 479             break;
 480         default:
 481             newrec.ExceptionCode    = STATUS_INVALID_DISPOSITION;
 482             newrec.ExceptionFlags   = EH_NONCONTINUABLE;
 483             newrec.ExceptionRecord  = pRecord;
 484             newrec.NumberParameters = 0;
 485             RtlRaiseException( &newrec );  /* never returns */
 486             break;
 487         }
 488         frame = __wine_pop_frame( frame );
 489     }
 490 }
 491
 492 /**********************************************************************/
 493
 494 #ifdef DEFINE_REGS_ENTRYPOINT
 495 DEFINE_REGS_ENTRYPOINT( RtlUnwind, 16, 16 )
 496 #else
 497 void WINAPI RtlUnwind( PVOID pEndFrame, PVOID unusedEip,
 498                        PEXCEPTION_RECORD pRecord, PVOID returnEax )
 499 {
 500     CONTEXT context;
 501     memset( &context, 0, sizeof(context) );
 502     __regs_RtlUnwind( pEndFrame, unusedEip, pRecord, returnEax, &context );
 503 }
 504 #endif
 505
 506
 507 /***********************************************************************
 508  *            RtlRaiseStatus  (NTDLL.@)
 509  *
 510  * Raise an exception with ExceptionCode = status
 511  */
 512 void WINAPI RtlRaiseStatus( NTSTATUS status )
 513 {
 514     EXCEPTION_RECORD ExceptionRec;
 515
 516     ExceptionRec.ExceptionCode    = status;
 517     ExceptionRec.ExceptionFlags   = EH_NONCONTINUABLE;
 518     ExceptionRec.ExceptionRecord  = NULL;
 519     ExceptionRec.NumberParameters = 0;
 520     RtlRaiseException( &ExceptionRec );
 521 }
 522
 523
 524 /*******************************************************************
 525  *         RtlAddVectoredExceptionHandler   (NTDLL.@)
 526  */
 527 PVOID WINAPI RtlAddVectoredExceptionHandler( ULONG first, PVECTORED_EXCEPTION_HANDLER func )
 528 {
 529     VECTORED_HANDLER *handler = RtlAllocateHeap( GetProcessHeap(), 0, sizeof(*handler) );
 530     if (handler)
 531     {
 532         handler->func = func;
 533         RtlEnterCriticalSection( &vectored_handlers_section );
 534         if (first) list_add_head( &vectored_handlers, &handler->entry );
 535         else list_add_tail( &vectored_handlers, &handler->entry );
 536         RtlLeaveCriticalSection( &vectored_handlers_section );
 537     }
 538     return handler;
 539 }
 540
 541
 542 /*******************************************************************
 543  *         RtlRemoveVectoredExceptionHandler   (NTDLL.@)
 544  */
 545 ULONG WINAPI RtlRemoveVectoredExceptionHandler( PVOID handler )
 546 {
 547     struct list *ptr;
 548     ULONG ret = FALSE;
 549
 550     RtlEnterCriticalSection( &vectored_handlers_section );
 551     LIST_FOR_EACH( ptr, &vectored_handlers )
 552     {
 553         VECTORED_HANDLER *curr_handler = LIST_ENTRY( ptr, VECTORED_HANDLER, entry );
 554         if (curr_handler == handler)
 555         {
 556             list_remove( ptr );
 557             ret = TRUE;
 558             break;
 559         }
 560     }
 561     RtlLeaveCriticalSection( &vectored_handlers_section );
 562     if (ret) RtlFreeHeap( GetProcessHeap(), 0, handler );
 563     return ret;
 564 }
 565
 566
 567 /*************************************************************
 568  *            __wine_exception_handler (NTDLL.@)
 569  *
 570  * Exception handler for exception blocks declared in Wine code.
 571  */
 572 DWORD __wine_exception_handler( EXCEPTION_RECORD *record, EXCEPTION_REGISTRATION_RECORD *frame,
 573                                 CONTEXT *context, EXCEPTION_REGISTRATION_RECORD **pdispatcher )
 574 {
 575     __WINE_FRAME *wine_frame = (__WINE_FRAME *)frame;
 576
 577     if (record->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND | EH_NESTED_CALL))
 578         return ExceptionContinueSearch;
 579
 580     if (wine_frame->u.filter == (void *)1)  /* special hack for page faults */
 581     {
 582         if (record->ExceptionCode != STATUS_ACCESS_VIOLATION)
 583             return ExceptionContinueSearch;
 584     }
 585     else if (wine_frame->u.filter)
 586     {
 587         EXCEPTION_POINTERS ptrs;
 588         ptrs.ExceptionRecord = record;
 589         ptrs.ContextRecord = context;
 590         switch(wine_frame->u.filter( &ptrs ))
 591         {
 592         case EXCEPTION_CONTINUE_SEARCH:
 593             return ExceptionContinueSearch;
 594         case EXCEPTION_CONTINUE_EXECUTION:
 595             return ExceptionContinueExecution;
 596         case EXCEPTION_EXECUTE_HANDLER:
 597             break;
 598         default:
 599             MESSAGE( "Invalid return value from exception filter\n" );
 600             assert( FALSE );
 601         }
 602     }
 603     /* hack to make GetExceptionCode() work in handler */
 604     wine_frame->ExceptionCode   = record->ExceptionCode;
 605     wine_frame->ExceptionRecord = wine_frame;
 606
 607     RtlUnwind( frame, 0, record, 0 );
 608     __wine_pop_frame( frame );
 609     siglongjmp( wine_frame->jmp, 1 );
 610 }
 611
 612
 613 /*************************************************************
 614  *            __wine_finally_handler (NTDLL.@)
 615  *
 616  * Exception handler for try/finally blocks declared in Wine code.
 617  */
 618 DWORD __wine_finally_handler( EXCEPTION_RECORD *record, EXCEPTION_REGISTRATION_RECORD *frame,
 619                               CONTEXT *context, EXCEPTION_REGISTRATION_RECORD **pdispatcher )
 620 {
 621     if (record->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND))
 622     {
 623         __WINE_FRAME *wine_frame = (__WINE_FRAME *)frame;
 624         wine_frame->u.finally_func( FALSE );
 625     }
 626     return ExceptionContinueSearch;
 627 }
 628
 629
 630 /*************************************************************
 631  *            __wine_spec_unimplemented_stub
 632  *
 633  * ntdll-specific implementation to avoid depending on kernel functions.
 634  * Can be removed once ntdll.spec no longer contains stubs.
 635  */
 636 void __wine_spec_unimplemented_stub( const char *module, const char *function )
 637 {
 638     EXCEPTION_RECORD record;
 639
 640     record.ExceptionCode    = EXCEPTION_WINE_STUB;
 641     record.ExceptionFlags   = EH_NONCONTINUABLE;
 642     record.ExceptionRecord  = NULL;
 643     record.ExceptionAddress = __wine_spec_unimplemented_stub;
 644     record.NumberParameters = 2;
 645     record.ExceptionInformation[0] = (ULONG_PTR)module;
 646     record.ExceptionInformation[1] = (ULONG_PTR)function;
 647     RtlRaiseException( &record );
 648 }