dlls/ntdll/exception.c

   1 /*
   2  * NT exception handling routines
   3  *
   4  * Copyright 1999 Turchanov Sergey
   5  * Copyright 1999 Alexandre Julliard
   6  */
   7
   8 #include "config.h"
   9
  10 #include <assert.h>
  11 #include <signal.h>
  12
  13 #include "winnt.h"
  14 #include "ntddk.h"
  15 #include "global.h"
  16 #include "wine/exception.h"
  17 #include "stackframe.h"
  18 #include "miscemu.h"
  19 #include "wine/server.h"
  20 #include "debugtools.h"
  21
  22 DEFAULT_DEBUG_CHANNEL(seh);
  23
  24 /* Exception record for handling exceptions happening inside exception handlers */
  25 typedef struct
  26 {
  27     EXCEPTION_FRAME frame;
  28     EXCEPTION_FRAME *prevFrame;
  29 } EXC_NESTED_FRAME;
  30
  31 #ifdef __i386__
  32 # define GET_IP(context) ((LPVOID)(context)->Eip)
  33 #endif
  34 #ifdef __sparc__
  35 # define GET_IP(context) ((LPVOID)(context)->pc)
  36 #endif
  37 #ifndef GET_IP
  38 # error You must define GET_IP for this CPU
  39 #endif
  40
  41 extern void SIGNAL_Unblock(void);
  42
  43 void WINAPI EXC_RtlRaiseException( PEXCEPTION_RECORD, PCONTEXT );
  44 void WINAPI EXC_RtlUnwind( PEXCEPTION_FRAME, LPVOID,
  45                            PEXCEPTION_RECORD, DWORD, PCONTEXT );
  46 void WINAPI EXC_NtRaiseException( PEXCEPTION_RECORD, PCONTEXT,
  47                                   BOOL, PCONTEXT );
  48
  49 /*******************************************************************
  50  *         EXC_RaiseHandler
  51  *
  52  * Handler for exceptions happening inside a handler.
  53  */
  54 static DWORD EXC_RaiseHandler( EXCEPTION_RECORD *rec, EXCEPTION_FRAME *frame,
  55                                CONTEXT *context, EXCEPTION_FRAME **dispatcher )
  56 {
  57     if (rec->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND))
  58         return ExceptionContinueSearch;
  59     /* We shouldn't get here so we store faulty frame in dispatcher */
  60     *dispatcher = ((EXC_NESTED_FRAME*)frame)->prevFrame;
  61     return ExceptionNestedException;
  62 }
  63
  64
  65 /*******************************************************************
  66  *         EXC_UnwindHandler
  67  *
  68  * Handler for exceptions happening inside an unwind handler.
  69  */
  70 static DWORD EXC_UnwindHandler( EXCEPTION_RECORD *rec, EXCEPTION_FRAME *frame,
  71                                 CONTEXT *context, EXCEPTION_FRAME **dispatcher )
  72 {
  73     if (!(rec->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND)))
  74         return ExceptionContinueSearch;
  75     /* We shouldn't get here so we store faulty frame in dispatcher */
  76     *dispatcher = ((EXC_NESTED_FRAME*)frame)->prevFrame;
  77     return ExceptionCollidedUnwind;
  78 }
  79
  80
  81 /*******************************************************************
  82  *         EXC_CallHandler
  83  *
  84  * Call an exception handler, setting up an exception frame to catch exceptions
  85  * happening during the handler execution.
  86  * Please do not change the first 4 parameters order in any way - some exceptions handlers
  87  * rely on Base Pointer (EBP) to have a fixed position related to the exception frame
  88  */
  89 static DWORD EXC_CallHandler( EXCEPTION_RECORD *record, EXCEPTION_FRAME *frame,
  90                               CONTEXT *context, EXCEPTION_FRAME **dispatcher,
  91                               PEXCEPTION_HANDLER handler, PEXCEPTION_HANDLER nested_handler)
  92 {
  93     EXC_NESTED_FRAME newframe;
  94     DWORD ret;
  95
  96     newframe.frame.Handler = nested_handler;
  97     newframe.prevFrame     = frame;
  98     __wine_push_frame( &newframe.frame );
  99     TRACE( "calling handler at %p code=%lx flags=%lx\n",
 100            handler, record->ExceptionCode, record->ExceptionFlags );
 101     ret = handler( record, frame, context, dispatcher );
 102     TRACE( "handler returned %lx\n", ret );
 103     __wine_pop_frame( &newframe.frame );
 104     return ret;
 105 }
 106
 107
 108 /**********************************************************************
 109  *           send_debug_event
 110  *
 111  * Send an EXCEPTION_DEBUG_EVENT event to the debugger.
 112  */
 113 static int send_debug_event( EXCEPTION_RECORD *rec, int first_chance, CONTEXT *context )
 114 {
 115     int ret;
 116     HANDLE handle = 0;
 117
 118     SERVER_START_REQ( queue_exception_event )
 119     {
 120         req->first   = first_chance;
 121         wine_server_add_data( req, context, sizeof(*context) );
 122         wine_server_add_data( req, rec, sizeof(*rec) );
 123         if (!wine_server_call( req )) handle = reply->handle;
 124     }
 125     SERVER_END_REQ;
 126     if (!handle) return 0;  /* no debugger present or other error */
 127
 128     /* No need to wait on the handle since the process gets suspended
 129      * once the event is passed to the debugger, so when we get back
 130      * here the event has been continued already.
 131      */
 132     SERVER_START_REQ( get_exception_status )
 133     {
 134         req->handle = handle;
 135         wine_server_set_reply( req, context, sizeof(*context) );
 136         wine_server_call( req );
 137         ret = reply->status;
 138     }
 139     SERVER_END_REQ;
 140     NtClose( handle );
 141     return ret;
 142 }
 143
 144
 145 /*******************************************************************
 146  *         EXC_DefaultHandling
 147  *
 148  * Default handling for exceptions. Called when we didn't find a suitable handler.
 149  */
 150 static void EXC_DefaultHandling( EXCEPTION_RECORD *rec, CONTEXT *context )
 151 {
 152     if (send_debug_event( rec, FALSE, context ) == DBG_CONTINUE) return;  /* continue execution */
 153
 154     if (rec->ExceptionFlags & EH_STACK_INVALID)
 155         ERR("Exception frame is not in stack limits => unable to dispatch exception.\n");
 156     else if (rec->ExceptionCode == EXCEPTION_NONCONTINUABLE_EXCEPTION)
 157         ERR("Process attempted to continue execution after noncontinuable exception.\n");
 158     else
 159         ERR("Unhandled exception code %lx flags %lx addr %p\n",
 160             rec->ExceptionCode, rec->ExceptionFlags, rec->ExceptionAddress );
 161     NtTerminateProcess( NtCurrentProcess(), 1 );
 162 }
 163
 164
 165 /***********************************************************************
 166  *              RtlRaiseException (NTDLL.@)
 167  */
 168 DEFINE_REGS_ENTRYPOINT_1( RtlRaiseException, EXC_RtlRaiseException, EXCEPTION_RECORD * );
 169 void WINAPI EXC_RtlRaiseException( EXCEPTION_RECORD *rec, CONTEXT *context )
 170 {
 171     PEXCEPTION_FRAME frame, dispatch, nested_frame;
 172     EXCEPTION_RECORD newrec;
 173     DWORD res, c;
 174
 175     TRACE( "code=%lx flags=%lx addr=%p\n", rec->ExceptionCode, rec->ExceptionFlags, rec->ExceptionAddress );
 176     for (c=0; c<rec->NumberParameters; c++) TRACE(" info[%ld]=%08lx\n", c, rec->ExceptionInformation[c]);
 177     if (rec->ExceptionCode == EXCEPTION_WINE_STUB) TRACE(" stub=%s\n", (char*)rec->ExceptionInformation[1]);
 178
 179     if (send_debug_event( rec, TRUE, context ) == DBG_CONTINUE) return;  /* continue execution */
 180
 181     SIGNAL_Unblock(); /* we may be in a signal handler, and exception handlers may jump out */
 182
 183     frame = NtCurrentTeb()->except;
 184     nested_frame = NULL;
 185     while (frame != (PEXCEPTION_FRAME)0xFFFFFFFF)
 186     {
 187         /* Check frame address */
 188         if (((void*)frame < NtCurrentTeb()->stack_low) ||
 189             ((void*)(frame+1) > NtCurrentTeb()->stack_top) ||
 190             (int)frame & 3)
 191         {
 192             rec->ExceptionFlags |= EH_STACK_INVALID;
 193             break;
 194         }
 195
 196         /* Call handler */
 197         res = EXC_CallHandler( rec, frame, context, &dispatch, frame->Handler, EXC_RaiseHandler );
 198         if (frame == nested_frame)
 199         {
 200             /* no longer nested */
 201             nested_frame = NULL;
 202             rec->ExceptionFlags &= ~EH_NESTED_CALL;
 203         }
 204
 205         switch(res)
 206         {
 207         case ExceptionContinueExecution:
 208             if (!(rec->ExceptionFlags & EH_NONCONTINUABLE)) return;
 209             newrec.ExceptionCode    = STATUS_NONCONTINUABLE_EXCEPTION;
 210             newrec.ExceptionFlags   = EH_NONCONTINUABLE;
 211             newrec.ExceptionRecord  = rec;
 212             newrec.NumberParameters = 0;
 213             RtlRaiseException( &newrec );  /* never returns */
 214             break;
 215         case ExceptionContinueSearch:
 216             break;
 217         case ExceptionNestedException:
 218             if (nested_frame < dispatch) nested_frame = dispatch;
 219             rec->ExceptionFlags |= EH_NESTED_CALL;
 220             break;
 221         default:
 222             newrec.ExceptionCode    = STATUS_INVALID_DISPOSITION;
 223             newrec.ExceptionFlags   = EH_NONCONTINUABLE;
 224             newrec.ExceptionRecord  = rec;
 225             newrec.NumberParameters = 0;
 226             RtlRaiseException( &newrec );  /* never returns */
 227             break;
 228         }
 229         frame = frame->Prev;
 230     }
 231     EXC_DefaultHandling( rec, context );
 232 }
 233
 234
 235 /*******************************************************************
 236  *              RtlUnwind (NTDLL.@)
 237  */
 238 DEFINE_REGS_ENTRYPOINT_4( RtlUnwind, EXC_RtlUnwind,
 239                           PEXCEPTION_FRAME, LPVOID, PEXCEPTION_RECORD, DWORD );
 240 void WINAPI EXC_RtlUnwind( PEXCEPTION_FRAME pEndFrame, LPVOID unusedEip,
 241                            PEXCEPTION_RECORD pRecord, DWORD returnEax,
 242                            CONTEXT *context )
 243 {
 244     EXCEPTION_RECORD record, newrec;
 245     PEXCEPTION_FRAME frame, dispatch;
 246
 247 #ifdef __i386__
 248     context->Eax = returnEax;
 249 #endif
 250
 251     /* build an exception record, if we do not have one */
 252     if (!pRecord)
 253     {
 254         record.ExceptionCode    = STATUS_UNWIND;
 255         record.ExceptionFlags   = 0;
 256         record.ExceptionRecord  = NULL;
 257         record.ExceptionAddress = GET_IP(context);
 258         record.NumberParameters = 0;
 259         pRecord = &record;
 260     }
 261
 262     pRecord->ExceptionFlags |= EH_UNWINDING | (pEndFrame ? 0 : EH_EXIT_UNWIND);
 263
 264     TRACE( "code=%lx flags=%lx\n", pRecord->ExceptionCode, pRecord->ExceptionFlags );
 265
 266     /* get chain of exception frames */
 267     frame = NtCurrentTeb()->except;
 268     while ((frame != (PEXCEPTION_FRAME)0xffffffff) && (frame != pEndFrame))
 269     {
 270         /* Check frame address */
 271         if (pEndFrame && (frame > pEndFrame))
 272         {
 273             newrec.ExceptionCode    = STATUS_INVALID_UNWIND_TARGET;
 274             newrec.ExceptionFlags   = EH_NONCONTINUABLE;
 275             newrec.ExceptionRecord  = pRecord;
 276             newrec.NumberParameters = 0;
 277             RtlRaiseException( &newrec );  /* never returns */
 278         }
 279         if (((void*)frame < NtCurrentTeb()->stack_low) ||
 280             ((void*)(frame+1) > NtCurrentTeb()->stack_top) ||
 281             (int)frame & 3)
 282         {
 283             newrec.ExceptionCode    = STATUS_BAD_STACK;
 284             newrec.ExceptionFlags   = EH_NONCONTINUABLE;
 285             newrec.ExceptionRecord  = pRecord;
 286             newrec.NumberParameters = 0;
 287             RtlRaiseException( &newrec );  /* never returns */
 288         }
 289
 290         /* Call handler */
 291         switch(EXC_CallHandler( pRecord, frame, context, &dispatch,
 292                                 frame->Handler, EXC_UnwindHandler ))
 293         {
 294         case ExceptionContinueSearch:
 295             break;
 296         case ExceptionCollidedUnwind:
 297             frame = dispatch;
 298             break;
 299         default:
 300             newrec.ExceptionCode    = STATUS_INVALID_DISPOSITION;
 301             newrec.ExceptionFlags   = EH_NONCONTINUABLE;
 302             newrec.ExceptionRecord  = pRecord;
 303             newrec.NumberParameters = 0;
 304             RtlRaiseException( &newrec );  /* never returns */
 305             break;
 306         }
 307         frame = __wine_pop_frame( frame );
 308     }
 309 }
 310
 311
 312 /*******************************************************************
 313  *              NtRaiseException (NTDLL.@)
 314  */
 315 DEFINE_REGS_ENTRYPOINT_3( NtRaiseException, EXC_NtRaiseException,
 316                           EXCEPTION_RECORD *, CONTEXT *, BOOL );
 317 void WINAPI EXC_NtRaiseException( EXCEPTION_RECORD *rec, CONTEXT *ctx,
 318                                   BOOL first, CONTEXT *context )
 319 {
 320     EXC_RtlRaiseException( rec, ctx );
 321     *context = *ctx;
 322 }
 323
 324
 325 /***********************************************************************
 326  *            RtlRaiseStatus  (NTDLL.@)
 327  *
 328  * Raise an exception with ExceptionCode = status
 329  */
 330 void WINAPI RtlRaiseStatus( NTSTATUS status )
 331 {
 332     EXCEPTION_RECORD ExceptionRec;
 333
 334     ExceptionRec.ExceptionCode    = status;
 335     ExceptionRec.ExceptionFlags   = EH_NONCONTINUABLE;
 336     ExceptionRec.ExceptionRecord  = NULL;
 337     ExceptionRec.NumberParameters = 0;
 338     RtlRaiseException( &ExceptionRec );
 339 }
 340
 341
 342 /*************************************************************
 343  *            __wine_exception_handler (NTDLL.@)
 344  *
 345  * Exception handler for exception blocks declared in Wine code.
 346  */
 347 DWORD __wine_exception_handler( EXCEPTION_RECORD *record, EXCEPTION_FRAME *frame,
 348                                 CONTEXT *context, LPVOID pdispatcher )
 349 {
 350     __WINE_FRAME *wine_frame = (__WINE_FRAME *)frame;
 351
 352     if (record->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND | EH_NESTED_CALL))
 353         return ExceptionContinueSearch;
 354     if (wine_frame->u.filter)
 355     {
 356         EXCEPTION_POINTERS ptrs;
 357         ptrs.ExceptionRecord = record;
 358         ptrs.ContextRecord = context;
 359         switch(wine_frame->u.filter( &ptrs ))
 360         {
 361         case EXCEPTION_CONTINUE_SEARCH:
 362             return ExceptionContinueSearch;
 363         case EXCEPTION_CONTINUE_EXECUTION:
 364             return ExceptionContinueExecution;
 365         case EXCEPTION_EXECUTE_HANDLER:
 366             break;
 367         default:
 368             MESSAGE( "Invalid return value from exception filter\n" );
 369             assert( FALSE );
 370         }
 371     }
 372     /* hack to make GetExceptionCode() work in handler */
 373     wine_frame->ExceptionCode   = record->ExceptionCode;
 374     wine_frame->ExceptionRecord = wine_frame;
 375
 376     RtlUnwind( frame, 0, record, 0 );
 377     __wine_pop_frame( frame );
 378     longjmp( wine_frame->jmp, 1 );
 379 }
 380
 381
 382 /*************************************************************
 383  *            __wine_finally_handler (NTDLL.@)
 384  *
 385  * Exception handler for try/finally blocks declared in Wine code.
 386  */
 387 DWORD __wine_finally_handler( EXCEPTION_RECORD *record, EXCEPTION_FRAME *frame,
 388                               CONTEXT *context, LPVOID pdispatcher )
 389 {
 390     __WINE_FRAME *wine_frame = (__WINE_FRAME *)frame;
 391
 392     if (!(record->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND)))
 393         return ExceptionContinueSearch;
 394     wine_frame->u.finally_func( FALSE );
 395     return ExceptionContinueSearch;
 396 }