git.oblomov.eu Git - wine/blob - dlls/msvcrt/except.c

   1 /*
   2  * msvcrt.dll exception handling
   3  *
   4  * Copyright 2000 Jon Griffiths
   5  * Copyright 2005 Juan Lang
   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  * FIXME: Incomplete support for nested exceptions/try block cleanup.
  22  */
  23
  24 #include "config.h"
  25 #include "wine/port.h"
  26
  27 #include <stdarg.h>
  28
  29 #include "windef.h"
  30 #include "winbase.h"
  31 #include "winternl.h"
  32 #include "wine/exception.h"
  33 #include "msvcrt.h"
  34 #include "excpt.h"
  35 #include "wincon.h"
  36 #include "wine/debug.h"
  37
  38 WINE_DEFAULT_DEBUG_CHANNEL(seh);
  39
  40 /* VC++ extensions to Win32 SEH */
  41 typedef struct _SCOPETABLE
  42 {
  43   int previousTryLevel;
  44   int (*lpfnFilter)(PEXCEPTION_POINTERS);
  45   int (*lpfnHandler)(void);
  46 } SCOPETABLE, *PSCOPETABLE;
  47
  48 typedef struct _MSVCRT_EXCEPTION_FRAME
  49 {
  50   EXCEPTION_REGISTRATION_RECORD *prev;
  51   void (*handler)(PEXCEPTION_RECORD, EXCEPTION_REGISTRATION_RECORD*,
  52                   PCONTEXT, PEXCEPTION_RECORD);
  53   PSCOPETABLE scopetable;
  54   int trylevel;
  55   int _ebp;
  56   PEXCEPTION_POINTERS xpointers;
  57 } MSVCRT_EXCEPTION_FRAME;
  58
  59 #define TRYLEVEL_END (-1) /* End of trylevel list */
  60
  61 #if defined(__GNUC__) && defined(__i386__)
  62 static inline void call_finally_block( void *code_block, void *base_ptr )
  63 {
  64     __asm__ __volatile__ ("movl %1,%%ebp; call *%%eax"
  65                           : : "a" (code_block), "g" (base_ptr));
  66 }
  67
  68 static inline int call_filter( int (*func)(PEXCEPTION_POINTERS), void *arg, void *ebp )
  69 {
  70     int ret;
  71     __asm__ __volatile__ ("pushl %%ebp; pushl %3; movl %2,%%ebp; call *%%eax; popl %%ebp; popl %%ebp"
  72                           : "=a" (ret)
  73                           : "0" (func), "r" (ebp), "r" (arg)
  74                           : "ecx", "edx", "memory" );
  75     return ret;
  76 }
  77
  78 static inline int call_unwind_func( int (*func)(void), void *ebp )
  79 {
  80     int ret;
  81     __asm__ __volatile__ ("pushl %%ebp\n\t"
  82                           "pushl %%ebx\n\t"
  83                           "pushl %%esi\n\t"
  84                           "pushl %%edi\n\t"
  85                           "movl %2,%%ebp\n\t"
  86                           "call *%0\n\t"
  87                           "popl %%edi\n\t"
  88                           "popl %%esi\n\t"
  89                           "popl %%ebx\n\t"
  90                           "popl %%ebp"
  91                           : "=a" (ret)
  92                           : "0" (func), "r" (ebp)
  93                           : "ecx", "edx", "memory" );
  94     return ret;
  95 }
  96
  97 #endif
  98
  99 static DWORD MSVCRT_nested_handler(PEXCEPTION_RECORD rec,
 100                                    EXCEPTION_REGISTRATION_RECORD* frame,
 101                                    PCONTEXT context,
 102                                    EXCEPTION_REGISTRATION_RECORD** dispatch)
 103 {
 104   if (!(rec->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND)))
 105     return ExceptionContinueSearch;
 106   *dispatch = frame;
 107   return ExceptionCollidedUnwind;
 108 }
 109
 110
 111 /*********************************************************************
 112  *              _EH_prolog (MSVCRT.@)
 113  */
 114 #ifdef __i386__
 115 /* Provided for VC++ binary compatibility only */
 116 __ASM_GLOBAL_FUNC(_EH_prolog,
 117                   "pushl $-1\n\t"
 118                   "pushl %eax\n\t"
 119                   "pushl %fs:0\n\t"
 120                   "movl  %esp, %fs:0\n\t"
 121                   "movl  12(%esp), %eax\n\t"
 122                   "movl  %ebp, 12(%esp)\n\t"
 123                   "leal  12(%esp), %ebp\n\t"
 124                   "pushl %eax\n\t"
 125                   "ret")
 126
 127 static void msvcrt_local_unwind2(MSVCRT_EXCEPTION_FRAME* frame, int trylevel, void *ebp)
 128 {
 129   EXCEPTION_REGISTRATION_RECORD reg;
 130
 131   TRACE("(%p,%d,%d)\n",frame, frame->trylevel, trylevel);
 132
 133   /* Register a handler in case of a nested exception */
 134   reg.Handler = MSVCRT_nested_handler;
 135   reg.Prev = NtCurrentTeb()->Tib.ExceptionList;
 136   __wine_push_frame(&reg);
 137
 138   while (frame->trylevel != TRYLEVEL_END && frame->trylevel != trylevel)
 139   {
 140       int level = frame->trylevel;
 141       frame->trylevel = frame->scopetable[level].previousTryLevel;
 142       if (!frame->scopetable[level].lpfnFilter)
 143       {
 144           TRACE( "__try block cleanup level %d handler %p ebp %p\n",
 145                  level, frame->scopetable[level].lpfnHandler, ebp );
 146           call_unwind_func( frame->scopetable[level].lpfnHandler, ebp );
 147       }
 148   }
 149   __wine_pop_frame(&reg);
 150   TRACE("unwound OK\n");
 151 }
 152
 153 /*******************************************************************
 154  *              _local_unwind2 (MSVCRT.@)
 155  */
 156 void CDECL _local_unwind2(MSVCRT_EXCEPTION_FRAME* frame, int trylevel)
 157 {
 158     msvcrt_local_unwind2( frame, trylevel, &frame->_ebp );
 159 }
 160
 161 #endif  /* __i386__ */
 162
 163 /*******************************************************************
 164  *              _global_unwind2 (MSVCRT.@)
 165  */
 166 void CDECL _global_unwind2(EXCEPTION_REGISTRATION_RECORD* frame)
 167 {
 168     TRACE("(%p)\n",frame);
 169     RtlUnwind( frame, 0, 0, 0 );
 170 }
 171
 172 /*********************************************************************
 173  *              _except_handler2 (MSVCRT.@)
 174  */
 175 int CDECL _except_handler2(PEXCEPTION_RECORD rec,
 176                            EXCEPTION_REGISTRATION_RECORD* frame,
 177                            PCONTEXT context,
 178                            EXCEPTION_REGISTRATION_RECORD** dispatcher)
 179 {
 180   FIXME("exception %x flags=%x at %p handler=%p %p %p stub\n",
 181         rec->ExceptionCode, rec->ExceptionFlags, rec->ExceptionAddress,
 182         frame->Handler, context, dispatcher);
 183   return ExceptionContinueSearch;
 184 }
 185
 186 /*********************************************************************
 187  *              _except_handler3 (MSVCRT.@)
 188  */
 189 int CDECL _except_handler3(PEXCEPTION_RECORD rec,
 190                            MSVCRT_EXCEPTION_FRAME* frame,
 191                            PCONTEXT context, void* dispatcher)
 192 {
 193 #if defined(__GNUC__) && defined(__i386__)
 194   int retval, trylevel;
 195   EXCEPTION_POINTERS exceptPtrs;
 196   PSCOPETABLE pScopeTable;
 197
 198   TRACE("exception %x flags=%x at %p handler=%p %p %p semi-stub\n",
 199         rec->ExceptionCode, rec->ExceptionFlags, rec->ExceptionAddress,
 200         frame->handler, context, dispatcher);
 201
 202   __asm__ __volatile__ ("cld");
 203
 204   if (rec->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND))
 205   {
 206     /* Unwinding the current frame */
 207     msvcrt_local_unwind2(frame, TRYLEVEL_END, &frame->_ebp);
 208     TRACE("unwound current frame, returning ExceptionContinueSearch\n");
 209     return ExceptionContinueSearch;
 210   }
 211   else
 212   {
 213     /* Hunting for handler */
 214     exceptPtrs.ExceptionRecord = rec;
 215     exceptPtrs.ContextRecord = context;
 216     *((DWORD *)frame-1) = (DWORD)&exceptPtrs;
 217     trylevel = frame->trylevel;
 218     pScopeTable = frame->scopetable;
 219
 220     while (trylevel != TRYLEVEL_END)
 221     {
 222       TRACE( "level %d prev %d filter %p\n", trylevel, pScopeTable[trylevel].previousTryLevel,
 223              pScopeTable[trylevel].lpfnFilter );
 224       if (pScopeTable[trylevel].lpfnFilter)
 225       {
 226         retval = call_filter( pScopeTable[trylevel].lpfnFilter, &exceptPtrs, &frame->_ebp );
 227
 228         TRACE("filter returned %s\n", retval == EXCEPTION_CONTINUE_EXECUTION ?
 229               "CONTINUE_EXECUTION" : retval == EXCEPTION_EXECUTE_HANDLER ?
 230               "EXECUTE_HANDLER" : "CONTINUE_SEARCH");
 231
 232         if (retval == EXCEPTION_CONTINUE_EXECUTION)
 233           return ExceptionContinueExecution;
 234
 235         if (retval == EXCEPTION_EXECUTE_HANDLER)
 236         {
 237           /* Unwind all higher frames, this one will handle the exception */
 238           _global_unwind2((EXCEPTION_REGISTRATION_RECORD*)frame);
 239           msvcrt_local_unwind2(frame, trylevel, &frame->_ebp);
 240
 241           /* Set our trylevel to the enclosing block, and call the __finally
 242            * code, which won't return
 243            */
 244           frame->trylevel = pScopeTable[trylevel].previousTryLevel;
 245           TRACE("__finally block %p\n",pScopeTable[trylevel].lpfnHandler);
 246           call_finally_block(pScopeTable[trylevel].lpfnHandler, &frame->_ebp);
 247           ERR("Returned from __finally block - expect crash!\n");
 248        }
 249       }
 250       trylevel = pScopeTable[trylevel].previousTryLevel;
 251     }
 252   }
 253 #else
 254   FIXME("exception %lx flags=%lx at %p handler=%p %p %p stub\n",
 255         rec->ExceptionCode, rec->ExceptionFlags, rec->ExceptionAddress,
 256         frame->handler, context, dispatcher);
 257 #endif
 258   TRACE("reached TRYLEVEL_END, returning ExceptionContinueSearch\n");
 259   return ExceptionContinueSearch;
 260 }
 261
 262 /*********************************************************************
 263  *              _abnormal_termination (MSVCRT.@)
 264  */
 265 int CDECL _abnormal_termination(void)
 266 {
 267   FIXME("(void)stub\n");
 268   return 0;
 269 }
 270
 271 /*
 272  * setjmp/longjmp implementation
 273  */
 274
 275 #ifdef __i386__
 276 #define MSVCRT_JMP_MAGIC 0x56433230 /* ID value for new jump structure */
 277 typedef void (__stdcall *MSVCRT_unwind_function)(const struct MSVCRT___JUMP_BUFFER *);
 278
 279 /* define an entrypoint for setjmp/setjmp3 that stores the registers in the jmp buf */
 280 /* and then jumps to the C backend function */
 281 #define DEFINE_SETJMP_ENTRYPOINT(name) \
 282     __ASM_GLOBAL_FUNC( name, \
 283                        "movl 4(%esp),%ecx\n\t"   /* jmp_buf */      \
 284                        "movl %ebp,0(%ecx)\n\t"   /* jmp_buf.Ebp */  \
 285                        "movl %ebx,4(%ecx)\n\t"   /* jmp_buf.Ebx */  \
 286                        "movl %edi,8(%ecx)\n\t"   /* jmp_buf.Edi */  \
 287                        "movl %esi,12(%ecx)\n\t"  /* jmp_buf.Esi */  \
 288                        "movl %esp,16(%ecx)\n\t"  /* jmp_buf.Esp */  \
 289                        "movl 0(%esp),%eax\n\t"                      \
 290                        "movl %eax,20(%ecx)\n\t"  /* jmp_buf.Eip */  \
 291                        "jmp " __ASM_NAME("__regs_") # name )
 292
 293 /* restore the registers from the jmp buf upon longjmp */
 294 extern void DECLSPEC_NORETURN longjmp_set_regs( struct MSVCRT___JUMP_BUFFER *jmp, int retval );
 295 __ASM_GLOBAL_FUNC( longjmp_set_regs,
 296                    "movl 4(%esp),%ecx\n\t"   /* jmp_buf */
 297                    "movl 8(%esp),%eax\n\t"   /* retval */
 298                    "movl 0(%ecx),%ebp\n\t"   /* jmp_buf.Ebp */
 299                    "movl 4(%ecx),%ebx\n\t"   /* jmp_buf.Ebx */
 300                    "movl 8(%ecx),%edi\n\t"   /* jmp_buf.Edi */
 301                    "movl 12(%ecx),%esi\n\t"  /* jmp_buf.Esi */
 302                    "movl 16(%ecx),%esp\n\t"  /* jmp_buf.Esp */
 303                    "addl $4,%esp\n\t"        /* get rid of return address */
 304                    "jmp *20(%ecx)\n\t"       /* jmp_buf.Eip */ )
 305
 306 /*
 307  * The signatures of the setjmp/longjmp functions do not match that
 308  * declared in the setjmp header so they don't follow the regular naming
 309  * convention to avoid conflicts.
 310  */
 311
 312 /*******************************************************************
 313  *              _setjmp (MSVCRT.@)
 314  */
 315 DEFINE_SETJMP_ENTRYPOINT(MSVCRT__setjmp)
 316 int CDECL __regs_MSVCRT__setjmp(struct MSVCRT___JUMP_BUFFER *jmp)
 317 {
 318     jmp->Registration = (unsigned long)NtCurrentTeb()->Tib.ExceptionList;
 319     if (jmp->Registration == ~0UL)
 320         jmp->TryLevel = TRYLEVEL_END;
 321     else
 322         jmp->TryLevel = ((MSVCRT_EXCEPTION_FRAME*)jmp->Registration)->trylevel;
 323
 324     TRACE("buf=%p ebx=%08lx esi=%08lx edi=%08lx ebp=%08lx esp=%08lx eip=%08lx frame=%08lx\n",
 325           jmp, jmp->Ebx, jmp->Esi, jmp->Edi, jmp->Ebp, jmp->Esp, jmp->Eip, jmp->Registration );
 326     return 0;
 327 }
 328
 329 /*******************************************************************
 330  *              _setjmp3 (MSVCRT.@)
 331  */
 332 DEFINE_SETJMP_ENTRYPOINT( MSVCRT__setjmp3 )
 333 int CDECL __regs_MSVCRT__setjmp3(struct MSVCRT___JUMP_BUFFER *jmp, int nb_args, ...)
 334 {
 335     jmp->Cookie = MSVCRT_JMP_MAGIC;
 336     jmp->UnwindFunc = 0;
 337     jmp->Registration = (unsigned long)NtCurrentTeb()->Tib.ExceptionList;
 338     if (jmp->Registration == ~0UL)
 339     {
 340         jmp->TryLevel = TRYLEVEL_END;
 341     }
 342     else
 343     {
 344         int i;
 345         va_list args;
 346
 347         va_start( args, nb_args );
 348         if (nb_args > 0) jmp->UnwindFunc = va_arg( args, unsigned long );
 349         if (nb_args > 1) jmp->TryLevel = va_arg( args, unsigned long );
 350         else jmp->TryLevel = ((MSVCRT_EXCEPTION_FRAME*)jmp->Registration)->trylevel;
 351         for (i = 0; i < 6 && i < nb_args - 2; i++)
 352             jmp->UnwindData[i] = va_arg( args, unsigned long );
 353         va_end( args );
 354     }
 355
 356     TRACE("buf=%p ebx=%08lx esi=%08lx edi=%08lx ebp=%08lx esp=%08lx eip=%08lx frame=%08lx\n",
 357           jmp, jmp->Ebx, jmp->Esi, jmp->Edi, jmp->Ebp, jmp->Esp, jmp->Eip, jmp->Registration );
 358     return 0;
 359 }
 360
 361 /*********************************************************************
 362  *              longjmp (MSVCRT.@)
 363  */
 364 int CDECL MSVCRT_longjmp(struct MSVCRT___JUMP_BUFFER *jmp, int retval)
 365 {
 366     unsigned long cur_frame = 0;
 367
 368     TRACE("buf=%p ebx=%08lx esi=%08lx edi=%08lx ebp=%08lx esp=%08lx eip=%08lx frame=%08lx retval=%08x\n",
 369           jmp, jmp->Ebx, jmp->Esi, jmp->Edi, jmp->Ebp, jmp->Esp, jmp->Eip, jmp->Registration, retval );
 370
 371     cur_frame=(unsigned long)NtCurrentTeb()->Tib.ExceptionList;
 372     TRACE("cur_frame=%lx\n",cur_frame);
 373
 374     if (cur_frame != jmp->Registration)
 375         _global_unwind2((EXCEPTION_REGISTRATION_RECORD*)jmp->Registration);
 376
 377     if (jmp->Registration)
 378     {
 379         if (!IsBadReadPtr(&jmp->Cookie, sizeof(long)) &&
 380             jmp->Cookie == MSVCRT_JMP_MAGIC && jmp->UnwindFunc)
 381         {
 382             MSVCRT_unwind_function unwind_func;
 383
 384             unwind_func=(MSVCRT_unwind_function)jmp->UnwindFunc;
 385             unwind_func(jmp);
 386         }
 387         else
 388             msvcrt_local_unwind2((MSVCRT_EXCEPTION_FRAME*)jmp->Registration,
 389                                  jmp->TryLevel, (void *)jmp->Ebp);
 390     }
 391
 392     if (!retval)
 393         retval = 1;
 394
 395     longjmp_set_regs( jmp, retval );
 396 }
 397
 398 /*********************************************************************
 399  *              _seh_longjmp_unwind (MSVCRT.@)
 400  */
 401 void __stdcall _seh_longjmp_unwind(struct MSVCRT___JUMP_BUFFER *jmp)
 402 {
 403     msvcrt_local_unwind2( (MSVCRT_EXCEPTION_FRAME *)jmp->Registration, jmp->TryLevel, (void *)jmp->Ebp );
 404 }
 405 #endif /* i386 */
 406
 407 static MSVCRT___sighandler_t sighandlers[MSVCRT_NSIG] = { MSVCRT_SIG_DFL };
 408
 409 static BOOL WINAPI msvcrt_console_handler(DWORD ctrlType)
 410 {
 411     BOOL ret = FALSE;
 412
 413     switch (ctrlType)
 414     {
 415     case CTRL_C_EVENT:
 416         if (sighandlers[MSVCRT_SIGINT])
 417         {
 418             if (sighandlers[MSVCRT_SIGINT] != MSVCRT_SIG_IGN)
 419                 sighandlers[MSVCRT_SIGINT](MSVCRT_SIGINT);
 420             ret = TRUE;
 421         }
 422         break;
 423     }
 424     return ret;
 425 }
 426
 427 typedef void (*float_handler)(int, int);
 428
 429 /* The exception codes are actually NTSTATUS values */
 430 static const struct
 431 {
 432     NTSTATUS status;
 433     int signal;
 434 } float_exception_map[] = {
 435  { EXCEPTION_FLT_DENORMAL_OPERAND, MSVCRT__FPE_DENORMAL },
 436  { EXCEPTION_FLT_DIVIDE_BY_ZERO, MSVCRT__FPE_ZERODIVIDE },
 437  { EXCEPTION_FLT_INEXACT_RESULT, MSVCRT__FPE_INEXACT },
 438  { EXCEPTION_FLT_INVALID_OPERATION, MSVCRT__FPE_INVALID },
 439  { EXCEPTION_FLT_OVERFLOW, MSVCRT__FPE_OVERFLOW },
 440  { EXCEPTION_FLT_STACK_CHECK, MSVCRT__FPE_STACKOVERFLOW },
 441  { EXCEPTION_FLT_UNDERFLOW, MSVCRT__FPE_UNDERFLOW },
 442 };
 443
 444 static LONG WINAPI msvcrt_exception_filter(struct _EXCEPTION_POINTERS *except)
 445 {
 446     LONG ret = EXCEPTION_CONTINUE_SEARCH;
 447     MSVCRT___sighandler_t handler;
 448
 449     if (!except || !except->ExceptionRecord)
 450         return EXCEPTION_CONTINUE_SEARCH;
 451
 452     switch (except->ExceptionRecord->ExceptionCode)
 453     {
 454     case EXCEPTION_ACCESS_VIOLATION:
 455         if ((handler = sighandlers[MSVCRT_SIGSEGV]) != MSVCRT_SIG_DFL)
 456         {
 457             if (handler != MSVCRT_SIG_IGN)
 458             {
 459                 sighandlers[MSVCRT_SIGSEGV] = MSVCRT_SIG_DFL;
 460                 handler(MSVCRT_SIGSEGV);
 461             }
 462             ret = EXCEPTION_CONTINUE_EXECUTION;
 463         }
 464         break;
 465     /* According to msdn,
 466      * the FPE signal handler takes as a second argument the type of
 467      * floating point exception.
 468      */
 469     case EXCEPTION_FLT_DENORMAL_OPERAND:
 470     case EXCEPTION_FLT_DIVIDE_BY_ZERO:
 471     case EXCEPTION_FLT_INEXACT_RESULT:
 472     case EXCEPTION_FLT_INVALID_OPERATION:
 473     case EXCEPTION_FLT_OVERFLOW:
 474     case EXCEPTION_FLT_STACK_CHECK:
 475     case EXCEPTION_FLT_UNDERFLOW:
 476         if ((handler = sighandlers[MSVCRT_SIGFPE]) != MSVCRT_SIG_DFL)
 477         {
 478             if (handler != MSVCRT_SIG_IGN)
 479             {
 480                 unsigned int i;
 481                 int float_signal = MSVCRT__FPE_INVALID;
 482
 483                 sighandlers[MSVCRT_SIGFPE] = MSVCRT_SIG_DFL;
 484                 for (i = 0; i < sizeof(float_exception_map) /
 485                          sizeof(float_exception_map[0]); i++)
 486                 {
 487                     if (float_exception_map[i].status ==
 488                         except->ExceptionRecord->ExceptionCode)
 489                     {
 490                         float_signal = float_exception_map[i].signal;
 491                         break;
 492                     }
 493                 }
 494                 ((float_handler)handler)(MSVCRT_SIGFPE, float_signal);
 495             }
 496             ret = EXCEPTION_CONTINUE_EXECUTION;
 497         }
 498         break;
 499     case EXCEPTION_ILLEGAL_INSTRUCTION:
 500     case EXCEPTION_PRIV_INSTRUCTION:
 501         if ((handler = sighandlers[MSVCRT_SIGILL]) != MSVCRT_SIG_DFL)
 502         {
 503             if (handler != MSVCRT_SIG_IGN)
 504             {
 505                 sighandlers[MSVCRT_SIGILL] = MSVCRT_SIG_DFL;
 506                 handler(MSVCRT_SIGILL);
 507             }
 508             ret = EXCEPTION_CONTINUE_EXECUTION;
 509         }
 510         break;
 511     }
 512     return ret;
 513 }
 514
 515 void msvcrt_init_signals(void)
 516 {
 517     SetConsoleCtrlHandler(msvcrt_console_handler, TRUE);
 518     SetUnhandledExceptionFilter(msvcrt_exception_filter);
 519 }
 520
 521 void msvcrt_free_signals(void)
 522 {
 523     SetConsoleCtrlHandler(msvcrt_console_handler, FALSE);
 524     SetUnhandledExceptionFilter(NULL);
 525 }
 526
 527 /*********************************************************************
 528  *              signal (MSVCRT.@)
 529  * Some signals may never be generated except through an explicit call to
 530  * raise.
 531  */
 532 MSVCRT___sighandler_t CDECL MSVCRT_signal(int sig, MSVCRT___sighandler_t func)
 533 {
 534     MSVCRT___sighandler_t ret = MSVCRT_SIG_ERR;
 535
 536     TRACE("(%d, %p)\n", sig, func);
 537
 538     if (func == MSVCRT_SIG_ERR) return MSVCRT_SIG_ERR;
 539
 540     switch (sig)
 541     {
 542     /* Cases handled internally.  Note SIGTERM is never generated by Windows,
 543      * so we effectively mask it.
 544      */
 545     case MSVCRT_SIGABRT:
 546     case MSVCRT_SIGFPE:
 547     case MSVCRT_SIGILL:
 548     case MSVCRT_SIGSEGV:
 549     case MSVCRT_SIGINT:
 550     case MSVCRT_SIGTERM:
 551         ret = sighandlers[sig];
 552         sighandlers[sig] = func;
 553         break;
 554     default:
 555         ret = MSVCRT_SIG_ERR;
 556     }
 557     return ret;
 558 }
 559
 560 /*********************************************************************
 561  *              raise (MSVCRT.@)
 562  */
 563 int CDECL MSVCRT_raise(int sig)
 564 {
 565     MSVCRT___sighandler_t handler;
 566
 567     TRACE("(%d)\n", sig);
 568
 569     switch (sig)
 570     {
 571     case MSVCRT_SIGABRT:
 572     case MSVCRT_SIGFPE:
 573     case MSVCRT_SIGILL:
 574     case MSVCRT_SIGSEGV:
 575     case MSVCRT_SIGINT:
 576     case MSVCRT_SIGTERM:
 577         handler = sighandlers[sig];
 578         if (handler == MSVCRT_SIG_DFL) MSVCRT__exit(3);
 579         if (handler != MSVCRT_SIG_IGN)
 580         {
 581             sighandlers[sig] = MSVCRT_SIG_DFL;
 582             if (sig == MSVCRT_SIGFPE)
 583                 ((float_handler)handler)(sig, MSVCRT__FPE_EXPLICITGEN);
 584             else
 585                 handler(sig);
 586         }
 587         break;
 588     default:
 589         return -1;
 590     }
 591     return 0;
 592 }
 593
 594 /*********************************************************************
 595  *              _XcptFilter (MSVCRT.@)
 596  */
 597 int CDECL _XcptFilter(NTSTATUS ex, PEXCEPTION_POINTERS ptr)
 598 {
 599     TRACE("(%08x,%p)\n", ex, ptr);
 600     /* I assume ptr->ExceptionRecord->ExceptionCode is the same as ex */
 601     return msvcrt_exception_filter(ptr);
 602 }