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  = wine_server_obj_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  = wine_server_obj_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     DWORD i;
 192     HANDLE handle = 0;
 193     client_ptr_t params[EXCEPTION_MAXIMUM_PARAMETERS];
 194
 195     if (!NtCurrentTeb()->Peb->BeingDebugged) return 0;  /* no debugger present */
 196
 197     for (i = 0; i < min( rec->NumberParameters, EXCEPTION_MAXIMUM_PARAMETERS ); i++)
 198         params[i] = rec->ExceptionInformation[i];
 199
 200     SERVER_START_REQ( queue_exception_event )
 201     {
 202         req->first   = first_chance;
 203         req->code    = rec->ExceptionCode;
 204         req->flags   = rec->ExceptionFlags;
 205         req->record  = wine_server_client_ptr( rec->ExceptionRecord );
 206         req->address = wine_server_client_ptr( rec->ExceptionAddress );
 207         req->len     = i * sizeof(params[0]);
 208         wine_server_add_data( req, params, req->len );
 209         wine_server_add_data( req, context, sizeof(*context) );
 210         if (!wine_server_call( req )) handle = wine_server_ptr_handle( reply->handle );
 211     }
 212     SERVER_END_REQ;
 213     if (!handle) return 0;
 214
 215     NTDLL_wait_for_multiple_objects( 1, &handle, SELECT_INTERRUPTIBLE, NULL, 0 );
 216
 217     SERVER_START_REQ( get_exception_status )
 218     {
 219         req->handle = wine_server_obj_handle( handle );
 220         wine_server_set_reply( req, context, sizeof(*context) );
 221         ret = wine_server_call( req );
 222     }
 223     SERVER_END_REQ;
 224     return ret;
 225 }
 226
 227
 228 /**********************************************************************
 229  *           call_vectored_handlers
 230  *
 231  * Call the vectored handlers chain.
 232  */
 233 static LONG call_vectored_handlers( EXCEPTION_RECORD *rec, CONTEXT *context )
 234 {
 235     struct list *ptr;
 236     LONG ret = EXCEPTION_CONTINUE_SEARCH;
 237     EXCEPTION_POINTERS except_ptrs;
 238
 239     except_ptrs.ExceptionRecord = rec;
 240     except_ptrs.ContextRecord = context;
 241
 242     RtlEnterCriticalSection( &vectored_handlers_section );
 243     LIST_FOR_EACH( ptr, &vectored_handlers )
 244     {
 245         VECTORED_HANDLER *handler = LIST_ENTRY( ptr, VECTORED_HANDLER, entry );
 246         ret = handler->func( &except_ptrs );
 247         if (ret == EXCEPTION_CONTINUE_EXECUTION) break;
 248     }
 249     RtlLeaveCriticalSection( &vectored_handlers_section );
 250     return ret;
 251 }
 252
 253
 254 /**********************************************************************
 255  *           call_stack_handlers
 256  *
 257  * Call the stack handlers chain.
 258  */
 259 static NTSTATUS call_stack_handlers( EXCEPTION_RECORD *rec, CONTEXT *context )
 260 {
 261     EXCEPTION_REGISTRATION_RECORD *frame, *dispatch, *nested_frame;
 262     DWORD res;
 263
 264     frame = NtCurrentTeb()->Tib.ExceptionList;
 265     nested_frame = NULL;
 266     while (frame != (EXCEPTION_REGISTRATION_RECORD*)~0UL)
 267     {
 268         /* Check frame address */
 269         if (((void*)frame < NtCurrentTeb()->Tib.StackLimit) ||
 270             ((void*)(frame+1) > NtCurrentTeb()->Tib.StackBase) ||
 271             (ULONG_PTR)frame & 3)
 272         {
 273             rec->ExceptionFlags |= EH_STACK_INVALID;
 274             break;
 275         }
 276
 277         /* Call handler */
 278         TRACE( "calling handler at %p code=%x flags=%x\n",
 279                frame->Handler, rec->ExceptionCode, rec->ExceptionFlags );
 280         res = EXC_CallHandler( rec, frame, context, &dispatch, frame->Handler, EXC_RaiseHandler );
 281         TRACE( "handler at %p returned %x\n", frame->Handler, res );
 282
 283         if (frame == nested_frame)
 284         {
 285             /* no longer nested */
 286             nested_frame = NULL;
 287             rec->ExceptionFlags &= ~EH_NESTED_CALL;
 288         }
 289
 290         switch(res)
 291         {
 292         case ExceptionContinueExecution:
 293             if (!(rec->ExceptionFlags & EH_NONCONTINUABLE)) return STATUS_SUCCESS;
 294             return STATUS_NONCONTINUABLE_EXCEPTION;
 295         case ExceptionContinueSearch:
 296             break;
 297         case ExceptionNestedException:
 298             if (nested_frame < dispatch) nested_frame = dispatch;
 299             rec->ExceptionFlags |= EH_NESTED_CALL;
 300             break;
 301         default:
 302             return STATUS_INVALID_DISPOSITION;
 303         }
 304         frame = frame->Prev;
 305     }
 306     return STATUS_UNHANDLED_EXCEPTION;
 307 }
 308
 309
 310 /*******************************************************************
 311  *              raise_exception
 312  *
 313  * Implementation of NtRaiseException.
 314  */
 315 static NTSTATUS raise_exception( EXCEPTION_RECORD *rec, CONTEXT *context, BOOL first_chance )
 316 {
 317     NTSTATUS status;
 318
 319     if (first_chance)
 320     {
 321         DWORD c;
 322
 323         TRACE( "code=%x flags=%x addr=%p\n",
 324                rec->ExceptionCode, rec->ExceptionFlags, rec->ExceptionAddress );
 325         for (c = 0; c < rec->NumberParameters; c++)
 326             TRACE( " info[%d]=%08lx\n", c, rec->ExceptionInformation[c] );
 327         if (rec->ExceptionCode == EXCEPTION_WINE_STUB)
 328         {
 329             if (rec->ExceptionInformation[1] >> 16)
 330                 MESSAGE( "wine: Call from %p to unimplemented function %s.%s, aborting\n",
 331                          rec->ExceptionAddress,
 332                          (char*)rec->ExceptionInformation[0], (char*)rec->ExceptionInformation[1] );
 333             else
 334                 MESSAGE( "wine: Call from %p to unimplemented function %s.%ld, aborting\n",
 335                          rec->ExceptionAddress,
 336                          (char*)rec->ExceptionInformation[0], rec->ExceptionInformation[1] );
 337         }
 338 #ifdef __i386__
 339         else
 340         {
 341             TRACE(" eax=%08x ebx=%08x ecx=%08x edx=%08x esi=%08x edi=%08x\n",
 342                   context->Eax, context->Ebx, context->Ecx,
 343                   context->Edx, context->Esi, context->Edi );
 344             TRACE(" ebp=%08x esp=%08x cs=%04x ds=%04x es=%04x fs=%04x gs=%04x flags=%08x\n",
 345                   context->Ebp, context->Esp, context->SegCs, context->SegDs,
 346                   context->SegEs, context->SegFs, context->SegGs, context->EFlags );
 347         }
 348 #endif
 349         status = send_debug_event( rec, TRUE, context );
 350         if (status == DBG_CONTINUE || status == DBG_EXCEPTION_HANDLED)
 351             return STATUS_SUCCESS;
 352
 353 #ifdef __i386__
 354         /* fix up instruction pointer in context for EXCEPTION_BREAKPOINT */
 355         if (rec->ExceptionCode == EXCEPTION_BREAKPOINT) context->Eip--;
 356 #endif
 357
 358         if (call_vectored_handlers( rec, context ) == EXCEPTION_CONTINUE_EXECUTION)
 359             return STATUS_SUCCESS;
 360
 361         if ((status = call_stack_handlers( rec, context )) != STATUS_UNHANDLED_EXCEPTION)
 362             return status;
 363     }
 364
 365     /* last chance exception */
 366
 367     status = send_debug_event( rec, FALSE, context );
 368     if (status != DBG_CONTINUE)
 369     {
 370         if (rec->ExceptionFlags & EH_STACK_INVALID)
 371             ERR("Exception frame is not in stack limits => unable to dispatch exception.\n");
 372         else if (rec->ExceptionCode == STATUS_NONCONTINUABLE_EXCEPTION)
 373             ERR("Process attempted to continue execution after noncontinuable exception.\n");
 374         else
 375             ERR("Unhandled exception code %x flags %x addr %p\n",
 376                 rec->ExceptionCode, rec->ExceptionFlags, rec->ExceptionAddress );
 377         NtTerminateProcess( NtCurrentProcess(), 1 );
 378     }
 379     return STATUS_SUCCESS;
 380 }
 381
 382
 383 /*******************************************************************
 384  *              NtRaiseException (NTDLL.@)
 385  */
 386 NTSTATUS WINAPI NtRaiseException( EXCEPTION_RECORD *rec, CONTEXT *context, BOOL first_chance )
 387 {
 388     NTSTATUS status = raise_exception( rec, context, first_chance );
 389     if (status == STATUS_SUCCESS) NtSetContextThread( GetCurrentThread(), context );
 390     return status;
 391 }
 392
 393 /***********************************************************************
 394  *              RtlCaptureContext (NTDLL.@)
 395  */
 396 void WINAPI __regs_RtlCaptureContext( CONTEXT *context_out, CONTEXT *context_in )
 397 {
 398     *context_out = *context_in;
 399 }
 400
 401 /**********************************************************************/
 402
 403 #ifdef DEFINE_REGS_ENTRYPOINT
 404 DEFINE_REGS_ENTRYPOINT( RtlCaptureContext, 4, 4 )
 405 #else
 406 void WINAPI RtlCaptureContext( CONTEXT *context_out )
 407 {
 408     memset( context_out, 0, sizeof(*context_out) );
 409 }
 410 #endif
 411
 412
 413 /***********************************************************************
 414  *              RtlRaiseException (NTDLL.@)
 415  */
 416 void WINAPI __regs_RtlRaiseException( EXCEPTION_RECORD *rec, CONTEXT *context )
 417 {
 418     NTSTATUS status = raise_exception( rec, context, TRUE );
 419     if (status != STATUS_SUCCESS)
 420     {
 421         EXCEPTION_RECORD newrec;
 422         newrec.ExceptionCode    = status;
 423         newrec.ExceptionFlags   = EH_NONCONTINUABLE;
 424         newrec.ExceptionRecord  = rec;
 425         newrec.NumberParameters = 0;
 426         RtlRaiseException( &newrec );  /* never returns */
 427     }
 428 }
 429
 430 /**********************************************************************/
 431
 432 #ifdef DEFINE_REGS_ENTRYPOINT
 433 DEFINE_REGS_ENTRYPOINT( RtlRaiseException, 4, 4 )
 434 #else
 435 void WINAPI RtlRaiseException( EXCEPTION_RECORD *rec )
 436 {
 437     CONTEXT context;
 438     RtlCaptureContext( &context );
 439     __regs_RtlRaiseException( rec, &context );
 440 }
 441 #endif
 442
 443
 444 /*******************************************************************
 445  *              RtlUnwind (NTDLL.@)
 446  */
 447 void WINAPI __regs_RtlUnwind( EXCEPTION_REGISTRATION_RECORD* pEndFrame, PVOID unusedEip,
 448                               PEXCEPTION_RECORD pRecord, PVOID returnEax, CONTEXT *context )
 449 {
 450     EXCEPTION_RECORD record, newrec;
 451     EXCEPTION_REGISTRATION_RECORD *frame, *dispatch;
 452     DWORD res;
 453
 454 #ifdef __i386__
 455     context->Eax = (DWORD)returnEax;
 456 #endif
 457
 458     /* build an exception record, if we do not have one */
 459     if (!pRecord)
 460     {
 461         record.ExceptionCode    = STATUS_UNWIND;
 462         record.ExceptionFlags   = 0;
 463         record.ExceptionRecord  = NULL;
 464         record.ExceptionAddress = GET_IP(context);
 465         record.NumberParameters = 0;
 466         pRecord = &record;
 467     }
 468
 469     pRecord->ExceptionFlags |= EH_UNWINDING | (pEndFrame ? 0 : EH_EXIT_UNWIND);
 470
 471     TRACE( "code=%x flags=%x\n", pRecord->ExceptionCode, pRecord->ExceptionFlags );
 472
 473     /* get chain of exception frames */
 474     frame = NtCurrentTeb()->Tib.ExceptionList;
 475     while ((frame != (EXCEPTION_REGISTRATION_RECORD*)~0UL) && (frame != pEndFrame))
 476     {
 477         /* Check frame address */
 478         if (pEndFrame && (frame > pEndFrame))
 479         {
 480             newrec.ExceptionCode    = STATUS_INVALID_UNWIND_TARGET;
 481             newrec.ExceptionFlags   = EH_NONCONTINUABLE;
 482             newrec.ExceptionRecord  = pRecord;
 483             newrec.NumberParameters = 0;
 484             RtlRaiseException( &newrec );  /* never returns */
 485         }
 486         if (((void*)frame < NtCurrentTeb()->Tib.StackLimit) ||
 487             ((void*)(frame+1) > NtCurrentTeb()->Tib.StackBase) ||
 488             (UINT_PTR)frame & 3)
 489         {
 490             newrec.ExceptionCode    = STATUS_BAD_STACK;
 491             newrec.ExceptionFlags   = EH_NONCONTINUABLE;
 492             newrec.ExceptionRecord  = pRecord;
 493             newrec.NumberParameters = 0;
 494             RtlRaiseException( &newrec );  /* never returns */
 495         }
 496
 497         /* Call handler */
 498         TRACE( "calling handler at %p code=%x flags=%x\n",
 499                frame->Handler, pRecord->ExceptionCode, pRecord->ExceptionFlags );
 500         res = EXC_CallHandler( pRecord, frame, context, &dispatch, frame->Handler, EXC_UnwindHandler );
 501         TRACE( "handler at %p returned %x\n", frame->Handler, res );
 502
 503         switch(res)
 504         {
 505         case ExceptionContinueSearch:
 506             break;
 507         case ExceptionCollidedUnwind:
 508             frame = dispatch;
 509             break;
 510         default:
 511             newrec.ExceptionCode    = STATUS_INVALID_DISPOSITION;
 512             newrec.ExceptionFlags   = EH_NONCONTINUABLE;
 513             newrec.ExceptionRecord  = pRecord;
 514             newrec.NumberParameters = 0;
 515             RtlRaiseException( &newrec );  /* never returns */
 516             break;
 517         }
 518         frame = __wine_pop_frame( frame );
 519     }
 520 }
 521
 522 /**********************************************************************/
 523
 524 #ifdef DEFINE_REGS_ENTRYPOINT
 525 DEFINE_REGS_ENTRYPOINT( RtlUnwind, 16, 16 )
 526 #else
 527 void WINAPI RtlUnwind( PVOID pEndFrame, PVOID unusedEip,
 528                        PEXCEPTION_RECORD pRecord, PVOID returnEax )
 529 {
 530     CONTEXT context;
 531     RtlCaptureContext( &context );
 532     __regs_RtlUnwind( pEndFrame, unusedEip, pRecord, returnEax, &context );
 533 }
 534 #endif
 535
 536
 537 /***********************************************************************
 538  *            RtlRaiseStatus  (NTDLL.@)
 539  *
 540  * Raise an exception with ExceptionCode = status
 541  */
 542 void WINAPI RtlRaiseStatus( NTSTATUS status )
 543 {
 544     EXCEPTION_RECORD ExceptionRec;
 545
 546     ExceptionRec.ExceptionCode    = status;
 547     ExceptionRec.ExceptionFlags   = EH_NONCONTINUABLE;
 548     ExceptionRec.ExceptionRecord  = NULL;
 549     ExceptionRec.NumberParameters = 0;
 550     RtlRaiseException( &ExceptionRec );
 551 }
 552
 553
 554 /*******************************************************************
 555  *         RtlAddVectoredExceptionHandler   (NTDLL.@)
 556  */
 557 PVOID WINAPI RtlAddVectoredExceptionHandler( ULONG first, PVECTORED_EXCEPTION_HANDLER func )
 558 {
 559     VECTORED_HANDLER *handler = RtlAllocateHeap( GetProcessHeap(), 0, sizeof(*handler) );
 560     if (handler)
 561     {
 562         handler->func = func;
 563         RtlEnterCriticalSection( &vectored_handlers_section );
 564         if (first) list_add_head( &vectored_handlers, &handler->entry );
 565         else list_add_tail( &vectored_handlers, &handler->entry );
 566         RtlLeaveCriticalSection( &vectored_handlers_section );
 567     }
 568     return handler;
 569 }
 570
 571
 572 /*******************************************************************
 573  *         RtlRemoveVectoredExceptionHandler   (NTDLL.@)
 574  */
 575 ULONG WINAPI RtlRemoveVectoredExceptionHandler( PVOID handler )
 576 {
 577     struct list *ptr;
 578     ULONG ret = FALSE;
 579
 580     RtlEnterCriticalSection( &vectored_handlers_section );
 581     LIST_FOR_EACH( ptr, &vectored_handlers )
 582     {
 583         VECTORED_HANDLER *curr_handler = LIST_ENTRY( ptr, VECTORED_HANDLER, entry );
 584         if (curr_handler == handler)
 585         {
 586             list_remove( ptr );
 587             ret = TRUE;
 588             break;
 589         }
 590     }
 591     RtlLeaveCriticalSection( &vectored_handlers_section );
 592     if (ret) RtlFreeHeap( GetProcessHeap(), 0, handler );
 593     return ret;
 594 }
 595
 596
 597 /*************************************************************
 598  *            __wine_spec_unimplemented_stub
 599  *
 600  * ntdll-specific implementation to avoid depending on kernel functions.
 601  * Can be removed once ntdll.spec no longer contains stubs.
 602  */
 603 void __wine_spec_unimplemented_stub( const char *module, const char *function )
 604 {
 605     EXCEPTION_RECORD record;
 606
 607     record.ExceptionCode    = EXCEPTION_WINE_STUB;
 608     record.ExceptionFlags   = EH_NONCONTINUABLE;
 609     record.ExceptionRecord  = NULL;
 610     record.ExceptionAddress = __wine_spec_unimplemented_stub;
 611     record.NumberParameters = 2;
 612     record.ExceptionInformation[0] = (ULONG_PTR)module;
 613     record.ExceptionInformation[1] = (ULONG_PTR)function;
 614     for (;;) RtlRaiseException( &record );
 615 }