dlls/winecrt0/exception.c

   1 /*
   2  * Support functions for Wine exception handling
   3  *
   4  * Copyright (c) 1999, 2010 Alexandre Julliard
   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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  19  */
  20
  21 #include "config.h"
  22 #include <stdarg.h>
  23 #include "winternl.h"
  24 #include "wine/exception.h"
  25
  26 #if defined(__x86_64__) && defined(__ASM_GLOBAL_FUNC)
  27 extern void __wine_unwind_trampoline(void);
  28 /* we need an extra call to make sure the stack is correctly aligned */
  29 __ASM_GLOBAL_FUNC( __wine_unwind_trampoline, "callq *%rax" );
  30 #endif
  31
  32 /* wrapper for RtlUnwind since it clobbers registers on Windows */
  33 void __wine_rtl_unwind( EXCEPTION_REGISTRATION_RECORD* frame, EXCEPTION_RECORD *record,
  34                         void (*target)(void) )
  35 {
  36 #if defined(__GNUC__) && defined(__i386__)
  37     int dummy1, dummy2, dummy3, dummy4;
  38     __asm__ __volatile__("pushl %%ebp\n\t"
  39                          "pushl %%ebx\n\t"
  40                          "pushl $0\n\t"
  41                          "pushl %3\n\t"
  42                          "pushl %2\n\t"
  43                          "pushl %1\n\t"
  44                          "call *%0\n\t"
  45                          "popl %%ebx\n\t"
  46                          "popl %%ebp"
  47                          : "=a" (dummy1), "=S" (dummy2), "=D" (dummy3), "=c" (dummy4)
  48                          : "0" (RtlUnwind), "1" (frame), "2" (target), "3" (record)
  49                          : "edx", "memory" );
  50 #elif defined(__x86_64__) && defined(__ASM_GLOBAL_FUNC)
  51     RtlUnwind( frame, __wine_unwind_trampoline, record, target );
  52 #else
  53     RtlUnwind( frame, target, record, 0 );
  54 #endif
  55     for (;;) target();
  56 }
  57
  58 static void DECLSPEC_NORETURN unwind_target(void)
  59 {
  60     __WINE_FRAME *wine_frame = (__WINE_FRAME *)__wine_get_frame();
  61     __wine_pop_frame( &wine_frame->frame );
  62     siglongjmp( wine_frame->jmp, 1 );
  63 }
  64
  65 static void DECLSPEC_NORETURN unwind_frame( EXCEPTION_RECORD *record,
  66                                             EXCEPTION_REGISTRATION_RECORD *frame )
  67 {
  68     __WINE_FRAME *wine_frame = (__WINE_FRAME *)frame;
  69
  70     /* hack to make GetExceptionCode() work in handler */
  71     wine_frame->ExceptionCode   = record->ExceptionCode;
  72     wine_frame->ExceptionRecord = wine_frame;
  73
  74     __wine_rtl_unwind( frame, record, unwind_target );
  75 }
  76
  77 DWORD __wine_exception_handler( EXCEPTION_RECORD *record,
  78                                 EXCEPTION_REGISTRATION_RECORD *frame,
  79                                 CONTEXT *context,
  80                                 EXCEPTION_REGISTRATION_RECORD **pdispatcher )
  81 {
  82     __WINE_FRAME *wine_frame = (__WINE_FRAME *)frame;
  83     EXCEPTION_POINTERS ptrs;
  84
  85     if (record->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND | EH_NESTED_CALL))
  86         return ExceptionContinueSearch;
  87
  88     ptrs.ExceptionRecord = record;
  89     ptrs.ContextRecord = context;
  90     switch(wine_frame->u.filter( &ptrs ))
  91     {
  92     case EXCEPTION_CONTINUE_SEARCH:
  93         return ExceptionContinueSearch;
  94     case EXCEPTION_CONTINUE_EXECUTION:
  95         return ExceptionContinueExecution;
  96     case EXCEPTION_EXECUTE_HANDLER:
  97         break;
  98     }
  99     unwind_frame( record, frame );
 100 }
 101
 102 DWORD __wine_exception_handler_page_fault( EXCEPTION_RECORD *record,
 103                                            EXCEPTION_REGISTRATION_RECORD *frame,
 104                                            CONTEXT *context,
 105                                            EXCEPTION_REGISTRATION_RECORD **pdispatcher )
 106 {
 107     if (record->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND | EH_NESTED_CALL))
 108         return ExceptionContinueSearch;
 109     if (record->ExceptionCode != STATUS_ACCESS_VIOLATION)
 110         return ExceptionContinueSearch;
 111     unwind_frame( record, frame );
 112 }
 113
 114 DWORD __wine_exception_handler_all( EXCEPTION_RECORD *record,
 115                                     EXCEPTION_REGISTRATION_RECORD *frame,
 116                                     CONTEXT *context,
 117                                     EXCEPTION_REGISTRATION_RECORD **pdispatcher )
 118 {
 119     if (record->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND | EH_NESTED_CALL))
 120         return ExceptionContinueSearch;
 121     unwind_frame( record, frame );
 122 }
 123
 124 DWORD __wine_finally_handler( EXCEPTION_RECORD *record,
 125                               EXCEPTION_REGISTRATION_RECORD *frame,
 126                               CONTEXT *context,
 127                               EXCEPTION_REGISTRATION_RECORD **pdispatcher )
 128 {
 129     if (record->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND))
 130     {
 131         __WINE_FRAME *wine_frame = (__WINE_FRAME *)frame;
 132         wine_frame->u.finally_func( FALSE );
 133     }
 134     return ExceptionContinueSearch;
 135 }