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

   1 /*
   2  * msvcrt.dll exception handling
   3  *
   4  * Copyright 2000 Jon Griffiths
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  *
  20  * NOTES:
  21  *
  22  * See http://www.microsoft.com/msj/0197/exception/exception.htm,
  23  * but don't believe all of it.
  24  *
  25  * FIXME: Incomplete support for nested exceptions/try block cleanup.
  26  */
  27
  28 #include "config.h"
  29 #include "wine/port.h"
  30
  31 #include "ntddk.h"
  32 #include "wine/exception.h"
  33 #include "thread.h"
  34 #include "msvcrt.h"
  35
  36 #include "msvcrt/setjmp.h"
  37 #include "msvcrt/excpt.h"
  38
  39
  40 #include "wine/debug.h"
  41
  42 WINE_DEFAULT_DEBUG_CHANNEL(msvcrt);
  43
  44 typedef void (*MSVCRT_sig_handler_func)(void);
  45
  46 /* VC++ extensions to Win32 SEH */
  47 typedef struct _SCOPETABLE
  48 {
  49   DWORD previousTryLevel;
  50   int (*lpfnFilter)(PEXCEPTION_POINTERS);
  51   int (*lpfnHandler)(void);
  52 } SCOPETABLE, *PSCOPETABLE;
  53
  54 typedef struct _MSVCRT_EXCEPTION_FRAME
  55 {
  56   EXCEPTION_FRAME *prev;
  57   void (*handler)(PEXCEPTION_RECORD, PEXCEPTION_FRAME,
  58                   PCONTEXT, PEXCEPTION_RECORD);
  59   PSCOPETABLE scopetable;
  60   DWORD trylevel;
  61   int _ebp;
  62   PEXCEPTION_POINTERS xpointers;
  63 } MSVCRT_EXCEPTION_FRAME;
  64
  65 #define TRYLEVEL_END 0xffffffff /* End of trylevel list */
  66
  67 #if defined(__GNUC__) && defined(__i386__)
  68
  69 inline static void call_finally_block( void *code_block, void *base_ptr )
  70 {
  71     __asm__ __volatile__ ("movl %1,%%ebp; call *%%eax" \
  72                           : : "a" (code_block), "g" (base_ptr));
  73 }
  74
  75 static DWORD MSVCRT_nested_handler(PEXCEPTION_RECORD rec,
  76                                    struct __EXCEPTION_FRAME* frame,
  77                                    PCONTEXT context WINE_UNUSED,
  78                                    struct __EXCEPTION_FRAME** dispatch)
  79 {
  80   if (rec->ExceptionFlags & 0x6)
  81     return ExceptionContinueSearch;
  82   *dispatch = frame;
  83   return ExceptionCollidedUnwind;
  84 }
  85 #endif
  86
  87
  88 /*********************************************************************
  89  *              _XcptFilter (MSVCRT.@)
  90  */
  91 int _XcptFilter(int ex, PEXCEPTION_POINTERS ptr)
  92 {
  93   FIXME("(%d,%p)semi-stub\n", ex, ptr);
  94   return UnhandledExceptionFilter(ptr);
  95 }
  96
  97 /*********************************************************************
  98  *              _EH_prolog (MSVCRT.@)
  99  */
 100 #ifdef __i386__
 101 /* Provided for VC++ binary compatability only */
 102 __ASM_GLOBAL_FUNC(_EH_prolog,
 103                   "pushl $0xff\n\t"
 104                   "pushl %eax\n\t"
 105                   "pushl %fs:0\n\t"
 106                   "movl  %esp, %fs:0\n\t"
 107                   "movl  12(%esp), %eax\n\t"
 108                   "movl  %ebp, 12(%esp)\n\t"
 109                   "leal  12(%esp), %ebp\n\t"
 110                   "pushl %eax\n\t"
 111                   "ret");
 112 #endif
 113
 114 /*******************************************************************
 115  *              _global_unwind2 (MSVCRT.@)
 116  */
 117 void _global_unwind2(PEXCEPTION_FRAME frame)
 118 {
 119     TRACE("(%p)\n",frame);
 120     RtlUnwind( frame, 0, 0, 0 );
 121 }
 122
 123 /*******************************************************************
 124  *              _local_unwind2 (MSVCRT.@)
 125  */
 126 void _local_unwind2(MSVCRT_EXCEPTION_FRAME* frame,
 127                     DWORD trylevel)
 128 {
 129   MSVCRT_EXCEPTION_FRAME *curframe = frame;
 130   DWORD curtrylevel = 0xfe;
 131   EXCEPTION_FRAME reg;
 132
 133   TRACE("(%p,%ld,%ld)\n",frame, frame->trylevel, trylevel);
 134
 135   /* Register a handler in case of a nested exception */
 136   reg.Handler = (PEXCEPTION_HANDLER)MSVCRT_nested_handler;
 137   reg.Prev = NtCurrentTeb()->except;
 138   __wine_push_frame(&reg);
 139
 140   while (frame->trylevel != TRYLEVEL_END && frame->trylevel != trylevel)
 141   {
 142     curtrylevel = frame->scopetable[frame->trylevel].previousTryLevel;
 143     curframe = frame;
 144     curframe->trylevel = curtrylevel;
 145     if (!frame->scopetable[curtrylevel].lpfnFilter)
 146     {
 147       ERR("__try block cleanup not implemented - expect crash!\n");
 148       /* FIXME: Remove current frame, set ebp, call
 149        * frame->scopetable[curtrylevel].lpfnHandler()
 150        */
 151     }
 152   }
 153   __wine_pop_frame(&reg);
 154   TRACE("unwound OK\n");
 155 }
 156
 157 /*********************************************************************
 158  *              _except_handler2 (MSVCRT.@)
 159  */
 160 int _except_handler2(PEXCEPTION_RECORD rec,
 161                      PEXCEPTION_FRAME frame,
 162                      PCONTEXT context,
 163                      PEXCEPTION_FRAME* dispatcher)
 164 {
 165   FIXME("exception %lx flags=%lx at %p handler=%p %p %p stub\n",
 166         rec->ExceptionCode, rec->ExceptionFlags, rec->ExceptionAddress,
 167         frame->Handler, context, dispatcher);
 168   return ExceptionContinueSearch;
 169 }
 170
 171 /*********************************************************************
 172  *              _except_handler3 (MSVCRT.@)
 173  */
 174 int _except_handler3(PEXCEPTION_RECORD rec,
 175                      MSVCRT_EXCEPTION_FRAME* frame,
 176                      PCONTEXT context, void* dispatcher)
 177 {
 178 #if defined(__GNUC__) && defined(__i386__)
 179   long retval, trylevel;
 180   EXCEPTION_POINTERS exceptPtrs;
 181   PSCOPETABLE pScopeTable;
 182
 183   TRACE("exception %lx flags=%lx at %p handler=%p %p %p semi-stub\n",
 184         rec->ExceptionCode, rec->ExceptionFlags, rec->ExceptionAddress,
 185         frame->handler, context, dispatcher);
 186
 187   __asm__ __volatile__ ("cld");
 188
 189   if (rec->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND))
 190   {
 191     /* Unwinding the current frame */
 192      _local_unwind2(frame, TRYLEVEL_END);
 193     return ExceptionContinueSearch;
 194   }
 195   else
 196   {
 197     /* Hunting for handler */
 198     exceptPtrs.ExceptionRecord = rec;
 199     exceptPtrs.ContextRecord = context;
 200     *((DWORD *)frame-1) = (DWORD)&exceptPtrs;
 201     trylevel = frame->trylevel;
 202     pScopeTable = frame->scopetable;
 203
 204     while (trylevel != TRYLEVEL_END)
 205     {
 206       if (pScopeTable[trylevel].lpfnFilter)
 207       {
 208         TRACE("filter = %p\n", pScopeTable[trylevel].lpfnFilter);
 209
 210         retval = pScopeTable[trylevel].lpfnFilter(&exceptPtrs);
 211
 212         TRACE("filter returned %s\n", retval == EXCEPTION_CONTINUE_EXECUTION ?
 213               "CONTINUE_EXECUTION" : retval == EXCEPTION_EXECUTE_HANDLER ?
 214               "EXECUTE_HANDLER" : "CONTINUE_SEARCH");
 215
 216         if (retval == EXCEPTION_CONTINUE_EXECUTION)
 217           return ExceptionContinueExecution;
 218
 219         if (retval == EXCEPTION_EXECUTE_HANDLER)
 220         {
 221           /* Unwind all higher frames, this one will handle the exception */
 222           _global_unwind2((PEXCEPTION_FRAME)frame);
 223           _local_unwind2(frame, trylevel);
 224
 225           /* Set our trylevel to the enclosing block, and call the __finally
 226            * code, which won't return
 227            */
 228           frame->trylevel = pScopeTable->previousTryLevel;
 229           TRACE("__finally block %p\n",pScopeTable[trylevel].lpfnHandler);
 230           call_finally_block(pScopeTable[trylevel].lpfnHandler, &frame->_ebp);
 231           ERR("Returned from __finally block - expect crash!\n");
 232        }
 233       }
 234       trylevel = pScopeTable->previousTryLevel;
 235     }
 236   }
 237 #else
 238   TRACE("exception %lx flags=%lx at %p handler=%p %p %p stub\n",
 239         rec->ExceptionCode, rec->ExceptionFlags, rec->ExceptionAddress,
 240         frame->handler, context, dispatcher);
 241 #endif
 242   return ExceptionContinueSearch;
 243 }
 244
 245 /*********************************************************************
 246  *              _abnormal_termination (MSVCRT.@)
 247  */
 248 int _abnormal_termination(void)
 249 {
 250   FIXME("(void)stub\n");
 251   return 0;
 252 }
 253
 254 /*
 255  * setjmp/longjmp implementation
 256  */
 257
 258 #ifdef __i386__
 259 #define MSVCRT_JMP_MAGIC 0x56433230 /* ID value for new jump structure */
 260 typedef void (*MSVCRT_unwind_function)(const void*);
 261
 262 /*
 263  * The signatures of the setjmp/longjmp functions do not match that
 264  * declared in the setjmp header so they don't follow the regular naming
 265  * convention to avoid conflicts.
 266  */
 267
 268 /*******************************************************************
 269  *              _setjmp (MSVCRT.@)
 270  */
 271 void _MSVCRT__setjmp(_JUMP_BUFFER *jmp, CONTEXT86* context)
 272 {
 273     TRACE("(%p)\n",jmp);
 274     jmp->Ebp = context->Ebp;
 275     jmp->Ebx = context->Ebx;
 276     jmp->Edi = context->Edi;
 277     jmp->Esi = context->Esi;
 278     jmp->Esp = context->Esp;
 279     jmp->Eip = context->Eip;
 280     jmp->Registration = (unsigned long)NtCurrentTeb()->except;
 281     if (jmp->Registration == TRYLEVEL_END)
 282         jmp->TryLevel = TRYLEVEL_END;
 283     else
 284         jmp->TryLevel = ((MSVCRT_EXCEPTION_FRAME*)jmp->Registration)->trylevel;
 285     TRACE("returning 0\n");
 286     context->Eax=0;
 287 }
 288
 289 /*******************************************************************
 290  *              _setjmp3 (MSVCRT.@)
 291  */
 292 void _MSVCRT__setjmp3(_JUMP_BUFFER *jmp, int nb_args, CONTEXT86* context)
 293 {
 294     TRACE("(%p,%d)\n",jmp,nb_args);
 295     jmp->Ebp = context->Ebp;
 296     jmp->Ebx = context->Ebx;
 297     jmp->Edi = context->Edi;
 298     jmp->Esi = context->Esi;
 299     jmp->Esp = context->Esp;
 300     jmp->Eip = context->Eip;
 301     jmp->Cookie = MSVCRT_JMP_MAGIC;
 302     jmp->UnwindFunc = 0;
 303     jmp->Registration = (unsigned long)NtCurrentTeb()->except;
 304     if (jmp->Registration == TRYLEVEL_END)
 305     {
 306         jmp->TryLevel = TRYLEVEL_END;
 307     }
 308     else
 309     {
 310         void **args = ((void**)context->Esp)+2;
 311
 312         if (nb_args > 0) jmp->UnwindFunc = (unsigned long)*args++;
 313         if (nb_args > 1) jmp->TryLevel = (unsigned long)*args++;
 314         else jmp->TryLevel = ((MSVCRT_EXCEPTION_FRAME*)jmp->Registration)->trylevel;
 315         if (nb_args > 2)
 316         {
 317             size_t size = (nb_args - 2) * sizeof(DWORD);
 318             memcpy( jmp->UnwindData, args, min( size, sizeof(jmp->UnwindData) ));
 319         }
 320     }
 321     TRACE("returning 0\n");
 322     context->Eax = 0;
 323 }
 324
 325 /*********************************************************************
 326  *              longjmp (MSVCRT.@)
 327  */
 328 void _MSVCRT_longjmp(_JUMP_BUFFER *jmp, int retval, CONTEXT86* context)
 329 {
 330     unsigned long cur_frame = 0;
 331
 332     TRACE("(%p,%d)\n", jmp, retval);
 333
 334     cur_frame=(unsigned long)NtCurrentTeb()->except;
 335     TRACE("cur_frame=%lx\n",cur_frame);
 336
 337     if (cur_frame != jmp->Registration)
 338         _global_unwind2((PEXCEPTION_FRAME)jmp->Registration);
 339
 340     if (jmp->Registration)
 341     {
 342         if (!IsBadReadPtr(&jmp->Cookie, sizeof(long)) &&
 343             jmp->Cookie == MSVCRT_JMP_MAGIC && jmp->UnwindFunc)
 344         {
 345             MSVCRT_unwind_function unwind_func;
 346
 347             unwind_func=(MSVCRT_unwind_function)jmp->UnwindFunc;
 348             unwind_func(jmp);
 349         }
 350         else
 351             _local_unwind2((MSVCRT_EXCEPTION_FRAME*)jmp->Registration,
 352                            jmp->TryLevel);
 353     }
 354
 355     if (!retval)
 356         retval = 1;
 357
 358     TRACE("Jump to %lx returning %d\n",jmp->Eip,retval);
 359     context->Ebp = jmp->Ebp;
 360     context->Ebx = jmp->Ebx;
 361     context->Edi = jmp->Edi;
 362     context->Esi = jmp->Esi;
 363     context->Esp = jmp->Esp;
 364     context->Eip = jmp->Eip;
 365     context->Eax = retval;
 366 }
 367 #endif /* i386 */
 368
 369 /*********************************************************************
 370  *              signal (MSVCRT.@)
 371  */
 372 void* MSVCRT_signal(int sig, MSVCRT_sig_handler_func func)
 373 {
 374   FIXME("(%d %p):stub\n", sig, func);
 375   return (void*)-1;
 376 }
 377
 378 /*********************************************************************
 379  *              __CxxFrameHandler (MSVCRT.@)
 380  */
 381 DWORD __CxxFrameHandler(PEXCEPTION_RECORD rec, struct __EXCEPTION_FRAME* frame,
 382                         PCONTEXT context, struct __EXCEPTION_FRAME** dispatch)
 383 {
 384     FIXME("(%p,%p,%p,%p):stub?\n",rec,frame,context,dispatch);
 385
 386     /* Copied from MSVCRT_nested_handler, I hope this is more
 387      * or less the right thing to do
 388      */
 389     if (rec->ExceptionFlags & 0x6)
 390         return ExceptionContinueSearch;
 391     *dispatch = frame;
 392     return ExceptionCollidedUnwind;
 393 }