dlls/msvcrt/except.c - wine - Git at Google

 /*
  * msvcrt.dll exception handling
  *
  * Copyright 2000 Jon Griffiths
  * Copyright 2005 Juan Lang
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with this library; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  *
  * NOTES:
  *
  * See http://www.microsoft.com/msj/0197/exception/exception.htm,
  * but don't believe all of it.
  *
  * FIXME: Incomplete support for nested exceptions/try block cleanup.
  */

 #include "config.h"
 #include "wine/port.h"

 #include <stdarg.h>

 #include "windef.h"
 #include "winbase.h"
 #include "winternl.h"
 #include "wine/exception.h"
 #include "msvcrt.h"
 #include "excpt.h"
 #include "wincon.h"
 #include "msvcrt/float.h"
 #include "wine/debug.h"

 WINE_DEFAULT_DEBUG_CHANNEL(seh);

 /* VC++ extensions to Win32 SEH */
 typedef struct _SCOPETABLE
 {
   int previousTryLevel;
   int (*lpfnFilter)(PEXCEPTION_POINTERS);
   int (*lpfnHandler)(void);
 } SCOPETABLE, *PSCOPETABLE;

 typedef struct _MSVCRT_EXCEPTION_FRAME
 {
   EXCEPTION_REGISTRATION_RECORD *prev;
   void (*handler)(PEXCEPTION_RECORD, EXCEPTION_REGISTRATION_RECORD*,
                   PCONTEXT, PEXCEPTION_RECORD);
   PSCOPETABLE scopetable;
   int trylevel;
   int _ebp;
   PEXCEPTION_POINTERS xpointers;
 } MSVCRT_EXCEPTION_FRAME;

 #define TRYLEVEL_END (-1) /* End of trylevel list */

 #if defined(__GNUC__) && defined(__i386__)
 static inline void call_finally_block( void *code_block, void *base_ptr )
 {
     __asm__ __volatile__ ("movl %1,%%ebp; call *%%eax"
                           : : "a" (code_block), "g" (base_ptr));
 }

 static inline int call_filter( int (*func)(PEXCEPTION_POINTERS), void *arg, void *ebp )
 {
     int ret;
     __asm__ __volatile__ ("pushl %%ebp; pushl %3; movl %2,%%ebp; call *%%eax; popl %%ebp; popl %%ebp"
                           : "=a" (ret)
                           : "0" (func), "r" (ebp), "r" (arg)
                           : "ecx", "edx", "memory" );
     return ret;
 }

 static inline int call_unwind_func( int (*func)(void), void *ebp )
 {
     int ret;
     __asm__ __volatile__ ("pushl %%ebp\n\t"
                           "pushl %%ebx\n\t"
                           "pushl %%esi\n\t"
                           "pushl %%edi\n\t"
                           "movl %2,%%ebp\n\t"
                           "call *%0\n\t"
                           "popl %%edi\n\t"
                           "popl %%esi\n\t"
                           "popl %%ebx\n\t"
                           "popl %%ebp"
                           : "=a" (ret)
                           : "0" (func), "r" (ebp)
                           : "ecx", "edx", "memory" );
     return ret;
 }

 #endif

 static DWORD MSVCRT_nested_handler(PEXCEPTION_RECORD rec,
                                    EXCEPTION_REGISTRATION_RECORD* frame,
                                    PCONTEXT context,
                                    EXCEPTION_REGISTRATION_RECORD** dispatch)
 {
   if (!(rec->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND)))
     return ExceptionContinueSearch;
   *dispatch = frame;
   return ExceptionCollidedUnwind;
 }


 /*********************************************************************
  *		_EH_prolog (MSVCRT.@)
  */
 #ifdef __i386__
 /* Provided for VC++ binary compatibility only */
 __ASM_GLOBAL_FUNC(_EH_prolog,
                   "pushl $-1\n\t"
                   "pushl %eax\n\t"
                   "pushl %fs:0\n\t"
                   "movl  %esp, %fs:0\n\t"
                   "movl  12(%esp), %eax\n\t"
                   "movl  %ebp, 12(%esp)\n\t"
                   "leal  12(%esp), %ebp\n\t"
                   "pushl %eax\n\t"
                   "ret")

 static void msvcrt_local_unwind2(MSVCRT_EXCEPTION_FRAME* frame, int trylevel, void *ebp)
 {
   EXCEPTION_REGISTRATION_RECORD reg;

   TRACE("(%p,%d,%d)\n",frame, frame->trylevel, trylevel);

   /* Register a handler in case of a nested exception */
   reg.Handler = MSVCRT_nested_handler;
   reg.Prev = NtCurrentTeb()->Tib.ExceptionList;
   __wine_push_frame(&reg);

   while (frame->trylevel != TRYLEVEL_END && frame->trylevel != trylevel)
   {
       int level = frame->trylevel;
       frame->trylevel = frame->scopetable[level].previousTryLevel;
       if (!frame->scopetable[level].lpfnFilter)
       {
           TRACE( "__try block cleanup level %d handler %p ebp %p\n",
                  level, frame->scopetable[level].lpfnHandler, ebp );
           call_unwind_func( frame->scopetable[level].lpfnHandler, ebp );
       }
   }
   __wine_pop_frame(&reg);
   TRACE("unwound OK\n");
 }

 /*******************************************************************
  *		_local_unwind2 (MSVCRT.@)
  */
 void CDECL _local_unwind2(MSVCRT_EXCEPTION_FRAME* frame, int trylevel)
 {
     msvcrt_local_unwind2( frame, trylevel, &frame->_ebp );
 }

 #endif  /* __i386__ */

 /*******************************************************************
  *		_global_unwind2 (MSVCRT.@)
  */
 void CDECL _global_unwind2(EXCEPTION_REGISTRATION_RECORD* frame)
 {
     TRACE("(%p)\n",frame);
     RtlUnwind( frame, 0, 0, 0 );
 }

 /*********************************************************************
  *		_except_handler2 (MSVCRT.@)
  */
 int CDECL _except_handler2(PEXCEPTION_RECORD rec,
                            EXCEPTION_REGISTRATION_RECORD* frame,
                            PCONTEXT context,
                            EXCEPTION_REGISTRATION_RECORD** dispatcher)
 {
   FIXME("exception %x flags=%x at %p handler=%p %p %p stub\n",
         rec->ExceptionCode, rec->ExceptionFlags, rec->ExceptionAddress,
         frame->Handler, context, dispatcher);
   return ExceptionContinueSearch;
 }

 /*********************************************************************
  *		_except_handler3 (MSVCRT.@)
  */
 int CDECL _except_handler3(PEXCEPTION_RECORD rec,
                            MSVCRT_EXCEPTION_FRAME* frame,
                            PCONTEXT context, void* dispatcher)
 {
 #if defined(__GNUC__) && defined(__i386__)
   int retval, trylevel;
   EXCEPTION_POINTERS exceptPtrs;
   PSCOPETABLE pScopeTable;

   TRACE("exception %x flags=%x at %p handler=%p %p %p semi-stub\n",
         rec->ExceptionCode, rec->ExceptionFlags, rec->ExceptionAddress,
         frame->handler, context, dispatcher);

   __asm__ __volatile__ ("cld");

   if (rec->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND))
   {
     /* Unwinding the current frame */
     msvcrt_local_unwind2(frame, TRYLEVEL_END, &frame->_ebp);
     TRACE("unwound current frame, returning ExceptionContinueSearch\n");
     return ExceptionContinueSearch;
   }
   else
   {
     /* Hunting for handler */
     exceptPtrs.ExceptionRecord = rec;
     exceptPtrs.ContextRecord = context;
     *((DWORD *)frame-1) = (DWORD)&exceptPtrs;
     trylevel = frame->trylevel;
     pScopeTable = frame->scopetable;

     while (trylevel != TRYLEVEL_END)
     {
       if (pScopeTable[trylevel].lpfnFilter)
       {
         TRACE("filter = %p\n", pScopeTable[trylevel].lpfnFilter);

         retval = call_filter( pScopeTable[trylevel].lpfnFilter, &exceptPtrs, &frame->_ebp );

         TRACE("filter returned %s\n", retval == EXCEPTION_CONTINUE_EXECUTION ?
               "CONTINUE_EXECUTION" : retval == EXCEPTION_EXECUTE_HANDLER ?
               "EXECUTE_HANDLER" : "CONTINUE_SEARCH");

         if (retval == EXCEPTION_CONTINUE_EXECUTION)
           return ExceptionContinueExecution;

         if (retval == EXCEPTION_EXECUTE_HANDLER)
         {
           /* Unwind all higher frames, this one will handle the exception */
           _global_unwind2((EXCEPTION_REGISTRATION_RECORD*)frame);
           msvcrt_local_unwind2(frame, trylevel, &frame->_ebp);

           /* Set our trylevel to the enclosing block, and call the __finally
            * code, which won't return
            */
           frame->trylevel = pScopeTable->previousTryLevel;
           TRACE("__finally block %p\n",pScopeTable[trylevel].lpfnHandler);
           call_finally_block(pScopeTable[trylevel].lpfnHandler, &frame->_ebp);
           ERR("Returned from __finally block - expect crash!\n");
        }
       }
       trylevel = pScopeTable->previousTryLevel;
     }
   }
 #else
   FIXME("exception %lx flags=%lx at %p handler=%p %p %p stub\n",
         rec->ExceptionCode, rec->ExceptionFlags, rec->ExceptionAddress,
         frame->handler, context, dispatcher);
 #endif
   TRACE("reached TRYLEVEL_END, returning ExceptionContinueSearch\n");
   return ExceptionContinueSearch;
 }

 /*********************************************************************
  *		_abnormal_termination (MSVCRT.@)
  */
 int CDECL _abnormal_termination(void)
 {
   FIXME("(void)stub\n");
   return 0;
 }

 /*
  * setjmp/longjmp implementation
  */

 #ifdef __i386__
 #define MSVCRT_JMP_MAGIC 0x56433230 /* ID value for new jump structure */
 typedef void (__stdcall *MSVCRT_unwind_function)(const struct MSVCRT___JUMP_BUFFER *);

 /* define an entrypoint for setjmp/setjmp3 that stores the registers in the jmp buf */
 /* and then jumps to the C backend function */
 #define DEFINE_SETJMP_ENTRYPOINT(name) \
     __ASM_GLOBAL_FUNC( name, \
                        "movl 4(%esp),%ecx\n\t"   /* jmp_buf */      \
                        "movl %ebp,0(%ecx)\n\t"   /* jmp_buf.Ebp */  \
                        "movl %ebx,4(%ecx)\n\t"   /* jmp_buf.Ebx */  \
                        "movl %edi,8(%ecx)\n\t"   /* jmp_buf.Edi */  \
                        "movl %esi,12(%ecx)\n\t"  /* jmp_buf.Esi */  \
                        "movl %esp,16(%ecx)\n\t"  /* jmp_buf.Esp */  \
                        "movl 0(%esp),%eax\n\t"                      \
                        "movl %eax,20(%ecx)\n\t"  /* jmp_buf.Eip */  \
                        "jmp " __ASM_NAME("__regs_") # name )

 /* restore the registers from the jmp buf upon longjmp */
 extern void DECLSPEC_NORETURN longjmp_set_regs( struct MSVCRT___JUMP_BUFFER *jmp, int retval );
 __ASM_GLOBAL_FUNC( longjmp_set_regs,
                    "movl 4(%esp),%ecx\n\t"   /* jmp_buf */
                    "movl 8(%esp),%eax\n\t"   /* retval */
                    "movl 0(%ecx),%ebp\n\t"   /* jmp_buf.Ebp */
                    "movl 4(%ecx),%ebx\n\t"   /* jmp_buf.Ebx */
                    "movl 8(%ecx),%edi\n\t"   /* jmp_buf.Edi */
                    "movl 12(%ecx),%esi\n\t"  /* jmp_buf.Esi */
                    "movl 16(%ecx),%esp\n\t"  /* jmp_buf.Esp */
                    "addl $4,%esp\n\t"        /* get rid of return address */
                    "jmp *20(%ecx)\n\t"       /* jmp_buf.Eip */ )

 /*
  * The signatures of the setjmp/longjmp functions do not match that
  * declared in the setjmp header so they don't follow the regular naming
  * convention to avoid conflicts.
  */

 /*******************************************************************
  *		_setjmp (MSVCRT.@)
  */
 DEFINE_SETJMP_ENTRYPOINT(MSVCRT__setjmp)
 int CDECL __regs_MSVCRT__setjmp(struct MSVCRT___JUMP_BUFFER *jmp)
 {
     jmp->Registration = (unsigned long)NtCurrentTeb()->Tib.ExceptionList;
     if (jmp->Registration == ~0UL)
         jmp->TryLevel = TRYLEVEL_END;
     else
         jmp->TryLevel = ((MSVCRT_EXCEPTION_FRAME*)jmp->Registration)->trylevel;

     TRACE("buf=%p ebx=%08lx esi=%08lx edi=%08lx ebp=%08lx esp=%08lx eip=%08lx frame=%08lx\n",
           jmp, jmp->Ebx, jmp->Esi, jmp->Edi, jmp->Ebp, jmp->Esp, jmp->Eip, jmp->Registration );
     return 0;
 }

 /*******************************************************************
  *		_setjmp3 (MSVCRT.@)
  */
 DEFINE_SETJMP_ENTRYPOINT( MSVCRT__setjmp3 )
 int CDECL __regs_MSVCRT__setjmp3(struct MSVCRT___JUMP_BUFFER *jmp, int nb_args, ...)
 {
     jmp->Cookie = MSVCRT_JMP_MAGIC;
     jmp->UnwindFunc = 0;
     jmp->Registration = (unsigned long)NtCurrentTeb()->Tib.ExceptionList;
     if (jmp->Registration == ~0UL)
     {
         jmp->TryLevel = TRYLEVEL_END;
     }
     else
     {
         int i;
         va_list args;

         va_start( args, nb_args );
         if (nb_args > 0) jmp->UnwindFunc = va_arg( args, unsigned long );
         if (nb_args > 1) jmp->TryLevel = va_arg( args, unsigned long );
         else jmp->TryLevel = ((MSVCRT_EXCEPTION_FRAME*)jmp->Registration)->trylevel;
         for (i = 0; i < 6 && i < nb_args - 2; i++)
             jmp->UnwindData[i] = va_arg( args, unsigned long );
         va_end( args );
     }

     TRACE("buf=%p ebx=%08lx esi=%08lx edi=%08lx ebp=%08lx esp=%08lx eip=%08lx frame=%08lx\n",
           jmp, jmp->Ebx, jmp->Esi, jmp->Edi, jmp->Ebp, jmp->Esp, jmp->Eip, jmp->Registration );
     return 0;
 }

 /*********************************************************************
  *		longjmp (MSVCRT.@)
  */
 int CDECL MSVCRT_longjmp(struct MSVCRT___JUMP_BUFFER *jmp, int retval)
 {
     unsigned long cur_frame = 0;

     TRACE("buf=%p ebx=%08lx esi=%08lx edi=%08lx ebp=%08lx esp=%08lx eip=%08lx frame=%08lx retval=%08x\n",
           jmp, jmp->Ebx, jmp->Esi, jmp->Edi, jmp->Ebp, jmp->Esp, jmp->Eip, jmp->Registration, retval );

     cur_frame=(unsigned long)NtCurrentTeb()->Tib.ExceptionList;
     TRACE("cur_frame=%lx\n",cur_frame);

     if (cur_frame != jmp->Registration)
         _global_unwind2((EXCEPTION_REGISTRATION_RECORD*)jmp->Registration);

     if (jmp->Registration)
     {
         if (!IsBadReadPtr(&jmp->Cookie, sizeof(long)) &&
             jmp->Cookie == MSVCRT_JMP_MAGIC && jmp->UnwindFunc)
         {
             MSVCRT_unwind_function unwind_func;

             unwind_func=(MSVCRT_unwind_function)jmp->UnwindFunc;
             unwind_func(jmp);
         }
         else
             msvcrt_local_unwind2((MSVCRT_EXCEPTION_FRAME*)jmp->Registration,
                                  jmp->TryLevel, (void *)jmp->Ebp);
     }

     if (!retval)
         retval = 1;

     longjmp_set_regs( jmp, retval );
 }

 /*********************************************************************
  *		_seh_longjmp_unwind (MSVCRT.@)
  */
 void __stdcall _seh_longjmp_unwind(struct MSVCRT___JUMP_BUFFER *jmp)
 {
     msvcrt_local_unwind2( (MSVCRT_EXCEPTION_FRAME *)jmp->Registration, jmp->TryLevel, (void *)jmp->Ebp );
 }
 #endif /* i386 */

 static MSVCRT___sighandler_t sighandlers[MSVCRT_NSIG] = { MSVCRT_SIG_DFL };

 static BOOL WINAPI msvcrt_console_handler(DWORD ctrlType)
 {
     BOOL ret = FALSE;

     switch (ctrlType)
     {
     case CTRL_C_EVENT:
         if (sighandlers[MSVCRT_SIGINT])
         {
             if (sighandlers[MSVCRT_SIGINT] != MSVCRT_SIG_IGN)
                 sighandlers[MSVCRT_SIGINT](MSVCRT_SIGINT);
             ret = TRUE;
         }
         break;
     }
     return ret;
 }

 typedef void (*float_handler)(int, int);

 /* The exception codes are actually NTSTATUS values */
 static const struct
 {
     NTSTATUS status;
     int signal;
 } float_exception_map[] = {
  { EXCEPTION_FLT_DENORMAL_OPERAND, _FPE_DENORMAL },
  { EXCEPTION_FLT_DIVIDE_BY_ZERO, _FPE_ZERODIVIDE },
  { EXCEPTION_FLT_INEXACT_RESULT, _FPE_INEXACT },
  { EXCEPTION_FLT_INVALID_OPERATION, _FPE_INVALID },
  { EXCEPTION_FLT_OVERFLOW, _FPE_OVERFLOW },
  { EXCEPTION_FLT_STACK_CHECK, _FPE_STACKOVERFLOW },
  { EXCEPTION_FLT_UNDERFLOW, _FPE_UNDERFLOW },
 };

 static LONG WINAPI msvcrt_exception_filter(struct _EXCEPTION_POINTERS *except)
 {
     LONG ret = EXCEPTION_CONTINUE_SEARCH;
     MSVCRT___sighandler_t handler;

     if (!except || !except->ExceptionRecord)
         return EXCEPTION_CONTINUE_SEARCH;

     switch (except->ExceptionRecord->ExceptionCode)
     {
     case EXCEPTION_ACCESS_VIOLATION:
         if ((handler = sighandlers[MSVCRT_SIGSEGV]) != MSVCRT_SIG_DFL)
         {
             if (handler != MSVCRT_SIG_IGN)
             {
                 sighandlers[MSVCRT_SIGSEGV] = MSVCRT_SIG_DFL;
                 handler(MSVCRT_SIGSEGV);
             }
             ret = EXCEPTION_CONTINUE_EXECUTION;
         }
         break;
     /* According to
      * http://msdn.microsoft.com/library/en-us/vclib/html/_CRT_signal.asp
      * the FPE signal handler takes as a second argument the type of
      * floating point exception.
      */
     case EXCEPTION_FLT_DENORMAL_OPERAND:
     case EXCEPTION_FLT_DIVIDE_BY_ZERO:
     case EXCEPTION_FLT_INEXACT_RESULT:
     case EXCEPTION_FLT_INVALID_OPERATION:
     case EXCEPTION_FLT_OVERFLOW:
     case EXCEPTION_FLT_STACK_CHECK:
     case EXCEPTION_FLT_UNDERFLOW:
         if ((handler = sighandlers[MSVCRT_SIGFPE]) != MSVCRT_SIG_DFL)
         {
             if (handler != MSVCRT_SIG_IGN)
             {
                 int i, float_signal = _FPE_INVALID;

                 sighandlers[MSVCRT_SIGFPE] = MSVCRT_SIG_DFL;
                 for (i = 0; i < sizeof(float_exception_map) /
                          sizeof(float_exception_map[0]); i++)
                 {
                     if (float_exception_map[i].status ==
                         except->ExceptionRecord->ExceptionCode)
                     {
                         float_signal = float_exception_map[i].signal;
                         break;
                     }
                 }
                 ((float_handler)handler)(MSVCRT_SIGFPE, float_signal);
             }
             ret = EXCEPTION_CONTINUE_EXECUTION;
         }
         break;
     case EXCEPTION_ILLEGAL_INSTRUCTION:
         if ((handler = sighandlers[MSVCRT_SIGILL]) != MSVCRT_SIG_DFL)
         {
             if (handler != MSVCRT_SIG_IGN)
             {
                 sighandlers[MSVCRT_SIGILL] = MSVCRT_SIG_DFL;
                 handler(MSVCRT_SIGILL);
             }
             ret = EXCEPTION_CONTINUE_EXECUTION;
         }
         break;
     }
     return ret;
 }

 void msvcrt_init_signals(void)
 {
     SetConsoleCtrlHandler(msvcrt_console_handler, TRUE);
     SetUnhandledExceptionFilter(msvcrt_exception_filter);
 }

 void msvcrt_free_signals(void)
 {
     SetConsoleCtrlHandler(msvcrt_console_handler, FALSE);
     SetUnhandledExceptionFilter(NULL);
 }

 /*********************************************************************
  *		signal (MSVCRT.@)
  * MS signal handling is described here:
  * http://msdn.microsoft.com/library/en-us/vclib/html/_CRT_signal.asp
  * Some signals may never be generated except through an explicit call to
  * raise.
  */
 MSVCRT___sighandler_t CDECL MSVCRT_signal(int sig, MSVCRT___sighandler_t func)
 {
     MSVCRT___sighandler_t ret = MSVCRT_SIG_ERR;

     TRACE("(%d, %p)\n", sig, func);

     if (func == MSVCRT_SIG_ERR) return MSVCRT_SIG_ERR;

     switch (sig)
     {
     /* Cases handled internally.  Note SIGTERM is never generated by Windows,
      * so we effectively mask it.
      */
     case MSVCRT_SIGABRT:
     case MSVCRT_SIGFPE:
     case MSVCRT_SIGILL:
     case MSVCRT_SIGSEGV:
     case MSVCRT_SIGINT:
     case MSVCRT_SIGTERM:
         ret = sighandlers[sig];
         sighandlers[sig] = func;
         break;
     default:
         ret = MSVCRT_SIG_ERR;
     }
     return ret;
 }

 /*********************************************************************
  *		raise (MSVCRT.@)
  */
 int CDECL MSVCRT_raise(int sig)
 {
     MSVCRT___sighandler_t handler;

     TRACE("(%d)\n", sig);

     switch (sig)
     {
     case MSVCRT_SIGABRT:
     case MSVCRT_SIGFPE:
     case MSVCRT_SIGILL:
     case MSVCRT_SIGSEGV:
     case MSVCRT_SIGINT:
     case MSVCRT_SIGTERM:
         handler = sighandlers[sig];
         if (handler == MSVCRT_SIG_DFL) MSVCRT__exit(3);
         if (handler != MSVCRT_SIG_IGN)
         {
             sighandlers[sig] = MSVCRT_SIG_DFL;
             if (sig == MSVCRT_SIGFPE)
                 ((float_handler)handler)(sig, _FPE_EXPLICITGEN);
             else
                 handler(sig);
         }
         break;
     default:
         return -1;
     }
     return 0;
 }

 /*********************************************************************
  *		_XcptFilter (MSVCRT.@)
  */
 int CDECL _XcptFilter(NTSTATUS ex, PEXCEPTION_POINTERS ptr)
 {
     TRACE("(%08x,%p)\n", ex, ptr);
     /* I assume ptr->ExceptionRecord->ExceptionCode is the same as ex */
     return msvcrt_exception_filter(ptr);
 }
	/*
	* msvcrt.dll exception handling
	*
	* Copyright 2000 Jon Griffiths
	* Copyright 2005 Juan Lang
	*
	* This library is free software; you can redistribute it and/or
	* modify it under the terms of the GNU Lesser General Public
	* License as published by the Free Software Foundation; either
	* version 2.1 of the License, or (at your option) any later version.
	*
	* This library is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* Lesser General Public License for more details.
	*
	* You should have received a copy of the GNU Lesser General Public
	* License along with this library; if not, write to the Free Software
	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
	*
	* NOTES:
	*
	* See http://www.microsoft.com/msj/0197/exception/exception.htm,
	* but don't believe all of it.
	*
	* FIXME: Incomplete support for nested exceptions/try block cleanup.
	*/

	#include "config.h"
	#include "wine/port.h"

	#include <stdarg.h>

	#include "windef.h"
	#include "winbase.h"
	#include "winternl.h"
	#include "wine/exception.h"
	#include "msvcrt.h"
	#include "excpt.h"
	#include "wincon.h"
	#include "msvcrt/float.h"
	#include "wine/debug.h"

	WINE_DEFAULT_DEBUG_CHANNEL(seh);

	/* VC++ extensions to Win32 SEH */
	typedef struct _SCOPETABLE
	{
	int previousTryLevel;
	int (*lpfnFilter)(PEXCEPTION_POINTERS);
	int (*lpfnHandler)(void);
	} SCOPETABLE, *PSCOPETABLE;

	typedef struct _MSVCRT_EXCEPTION_FRAME
	{
	EXCEPTION_REGISTRATION_RECORD *prev;
	void (handler)(PEXCEPTION_RECORD, EXCEPTION_REGISTRATION_RECORD,
	PCONTEXT, PEXCEPTION_RECORD);
	PSCOPETABLE scopetable;
	int trylevel;
	int _ebp;
	PEXCEPTION_POINTERS xpointers;
	} MSVCRT_EXCEPTION_FRAME;

	#define TRYLEVEL_END (-1) /* End of trylevel list */

	#if defined(__GNUC__) && defined(__i386__)
	static inline void call_finally_block( void code_block, void base_ptr )
	{
	__asm__ __volatile__ ("movl %1,%%ebp; call *%%eax"
	: : "a" (code_block), "g" (base_ptr));
	}

	static inline int call_filter( int (func)(PEXCEPTION_POINTERS), void arg, void *ebp )
	{
	int ret;
	__asm__ __volatile__ ("pushl %%ebp; pushl %3; movl %2,%%ebp; call *%%eax; popl %%ebp; popl %%ebp"
	: "=a" (ret)
	: "0" (func), "r" (ebp), "r" (arg)
	: "ecx", "edx", "memory" );
	return ret;
	}

	static inline int call_unwind_func( int (func)(void), void ebp )
	{
	int ret;
	__asm__ __volatile__ ("pushl %%ebp\n\t"
	"pushl %%ebx\n\t"
	"pushl %%esi\n\t"
	"pushl %%edi\n\t"
	"movl %2,%%ebp\n\t"
	"call *%0\n\t"
	"popl %%edi\n\t"
	"popl %%esi\n\t"
	"popl %%ebx\n\t"
	"popl %%ebp"
	: "=a" (ret)
	: "0" (func), "r" (ebp)
	: "ecx", "edx", "memory" );
	return ret;
	}

	#endif

	static DWORD MSVCRT_nested_handler(PEXCEPTION_RECORD rec,
	EXCEPTION_REGISTRATION_RECORD* frame,
	PCONTEXT context,
	EXCEPTION_REGISTRATION_RECORD** dispatch)
	{
	if (!(rec->ExceptionFlags & (EH_UNWINDING \| EH_EXIT_UNWIND)))
	return ExceptionContinueSearch;
	*dispatch = frame;
	return ExceptionCollidedUnwind;
	}


	/*********************************************************************
	* _EH_prolog (MSVCRT.@)
	*/
	#ifdef __i386__
	/* Provided for VC++ binary compatibility only */
	__ASM_GLOBAL_FUNC(_EH_prolog,
	"pushl $-1\n\t"
	"pushl %eax\n\t"
	"pushl %fs:0\n\t"
	"movl %esp, %fs:0\n\t"
	"movl 12(%esp), %eax\n\t"
	"movl %ebp, 12(%esp)\n\t"
	"leal 12(%esp), %ebp\n\t"
	"pushl %eax\n\t"
	"ret")

	static void msvcrt_local_unwind2(MSVCRT_EXCEPTION_FRAME* frame, int trylevel, void *ebp)
	{
	EXCEPTION_REGISTRATION_RECORD reg;

	TRACE("(%p,%d,%d)\n",frame, frame->trylevel, trylevel);

	/* Register a handler in case of a nested exception */
	reg.Handler = MSVCRT_nested_handler;
	reg.Prev = NtCurrentTeb()->Tib.ExceptionList;
	__wine_push_frame(&reg);

	while (frame->trylevel != TRYLEVEL_END && frame->trylevel != trylevel)
	{
	int level = frame->trylevel;
	frame->trylevel = frame->scopetable[level].previousTryLevel;
	if (!frame->scopetable[level].lpfnFilter)
	{
	TRACE( "__try block cleanup level %d handler %p ebp %p\n",
	level, frame->scopetable[level].lpfnHandler, ebp );
	call_unwind_func( frame->scopetable[level].lpfnHandler, ebp );
	}
	}
	__wine_pop_frame(&reg);
	TRACE("unwound OK\n");
	}

	/*******************************************************************
	* _local_unwind2 (MSVCRT.@)
	*/
	void CDECL _local_unwind2(MSVCRT_EXCEPTION_FRAME* frame, int trylevel)
	{
	msvcrt_local_unwind2( frame, trylevel, &frame->_ebp );
	}

	#endif /* __i386__ */

	/*******************************************************************
	* _global_unwind2 (MSVCRT.@)
	*/
	void CDECL _global_unwind2(EXCEPTION_REGISTRATION_RECORD* frame)
	{
	TRACE("(%p)\n",frame);
	RtlUnwind( frame, 0, 0, 0 );
	}

	/*********************************************************************
	* _except_handler2 (MSVCRT.@)
	*/
	int CDECL _except_handler2(PEXCEPTION_RECORD rec,
	EXCEPTION_REGISTRATION_RECORD* frame,
	PCONTEXT context,
	EXCEPTION_REGISTRATION_RECORD** dispatcher)
	{
	FIXME("exception %x flags=%x at %p handler=%p %p %p stub\n",
	rec->ExceptionCode, rec->ExceptionFlags, rec->ExceptionAddress,
	frame->Handler, context, dispatcher);
	return ExceptionContinueSearch;
	}

	/*********************************************************************
	* _except_handler3 (MSVCRT.@)
	*/
	int CDECL _except_handler3(PEXCEPTION_RECORD rec,
	MSVCRT_EXCEPTION_FRAME* frame,
	PCONTEXT context, void* dispatcher)
	{
	#if defined(__GNUC__) && defined(__i386__)
	int retval, trylevel;
	EXCEPTION_POINTERS exceptPtrs;
	PSCOPETABLE pScopeTable;

	TRACE("exception %x flags=%x at %p handler=%p %p %p semi-stub\n",
	rec->ExceptionCode, rec->ExceptionFlags, rec->ExceptionAddress,
	frame->handler, context, dispatcher);

	__asm__ __volatile__ ("cld");

	if (rec->ExceptionFlags & (EH_UNWINDING \| EH_EXIT_UNWIND))
	{
	/* Unwinding the current frame */
	msvcrt_local_unwind2(frame, TRYLEVEL_END, &frame->_ebp);
	TRACE("unwound current frame, returning ExceptionContinueSearch\n");
	return ExceptionContinueSearch;
	}
	else
	{
	/* Hunting for handler */
	exceptPtrs.ExceptionRecord = rec;
	exceptPtrs.ContextRecord = context;
	((DWORD )frame-1) = (DWORD)&exceptPtrs;
	trylevel = frame->trylevel;
	pScopeTable = frame->scopetable;

	while (trylevel != TRYLEVEL_END)
	{
	if (pScopeTable[trylevel].lpfnFilter)
	{
	TRACE("filter = %p\n", pScopeTable[trylevel].lpfnFilter);

	retval = call_filter( pScopeTable[trylevel].lpfnFilter, &exceptPtrs, &frame->_ebp );

	TRACE("filter returned %s\n", retval == EXCEPTION_CONTINUE_EXECUTION ?
	"CONTINUE_EXECUTION" : retval == EXCEPTION_EXECUTE_HANDLER ?
	"EXECUTE_HANDLER" : "CONTINUE_SEARCH");

	if (retval == EXCEPTION_CONTINUE_EXECUTION)
	return ExceptionContinueExecution;

	if (retval == EXCEPTION_EXECUTE_HANDLER)
	{
	/* Unwind all higher frames, this one will handle the exception */
	_global_unwind2((EXCEPTION_REGISTRATION_RECORD*)frame);
	msvcrt_local_unwind2(frame, trylevel, &frame->_ebp);

	/* Set our trylevel to the enclosing block, and call the __finally
	* code, which won't return
	*/
	frame->trylevel = pScopeTable->previousTryLevel;
	TRACE("__finally block %p\n",pScopeTable[trylevel].lpfnHandler);
	call_finally_block(pScopeTable[trylevel].lpfnHandler, &frame->_ebp);
	ERR("Returned from __finally block - expect crash!\n");
	}
	}
	trylevel = pScopeTable->previousTryLevel;
	}
	}
	#else
	FIXME("exception %lx flags=%lx at %p handler=%p %p %p stub\n",
	rec->ExceptionCode, rec->ExceptionFlags, rec->ExceptionAddress,
	frame->handler, context, dispatcher);
	#endif
	TRACE("reached TRYLEVEL_END, returning ExceptionContinueSearch\n");
	return ExceptionContinueSearch;
	}

	/*********************************************************************
	* _abnormal_termination (MSVCRT.@)
	*/
	int CDECL _abnormal_termination(void)
	{
	FIXME("(void)stub\n");
	return 0;
	}

	/*
	* setjmp/longjmp implementation
	*/

	#ifdef __i386__
	#define MSVCRT_JMP_MAGIC 0x56433230 /* ID value for new jump structure */
	typedef void (__stdcall MSVCRT_unwind_function)(const struct MSVCRT___JUMP_BUFFER );

	/* define an entrypoint for setjmp/setjmp3 that stores the registers in the jmp buf */
	/* and then jumps to the C backend function */
	#define DEFINE_SETJMP_ENTRYPOINT(name) \
	__ASM_GLOBAL_FUNC( name, \
	"movl 4(%esp),%ecx\n\t" /* jmp_buf */ \
	"movl %ebp,0(%ecx)\n\t" /* jmp_buf.Ebp */ \
	"movl %ebx,4(%ecx)\n\t" /* jmp_buf.Ebx */ \
	"movl %edi,8(%ecx)\n\t" /* jmp_buf.Edi */ \
	"movl %esi,12(%ecx)\n\t" /* jmp_buf.Esi */ \
	"movl %esp,16(%ecx)\n\t" /* jmp_buf.Esp */ \
	"movl 0(%esp),%eax\n\t" \
	"movl %eax,20(%ecx)\n\t" /* jmp_buf.Eip */ \
	"jmp " __ASM_NAME("__regs_") # name )

	/* restore the registers from the jmp buf upon longjmp */
	extern void DECLSPEC_NORETURN longjmp_set_regs( struct MSVCRT___JUMP_BUFFER *jmp, int retval );
	__ASM_GLOBAL_FUNC( longjmp_set_regs,
	"movl 4(%esp),%ecx\n\t" /* jmp_buf */
	"movl 8(%esp),%eax\n\t" /* retval */
	"movl 0(%ecx),%ebp\n\t" /* jmp_buf.Ebp */
	"movl 4(%ecx),%ebx\n\t" /* jmp_buf.Ebx */
	"movl 8(%ecx),%edi\n\t" /* jmp_buf.Edi */
	"movl 12(%ecx),%esi\n\t" /* jmp_buf.Esi */
	"movl 16(%ecx),%esp\n\t" /* jmp_buf.Esp */
	"addl $4,%esp\n\t" /* get rid of return address */
	"jmp 20(%ecx)\n\t" / jmp_buf.Eip */ )

	/*
	* The signatures of the setjmp/longjmp functions do not match that
	* declared in the setjmp header so they don't follow the regular naming
	* convention to avoid conflicts.
	*/

	/*******************************************************************
	* _setjmp (MSVCRT.@)
	*/
	DEFINE_SETJMP_ENTRYPOINT(MSVCRT__setjmp)
	int CDECL __regs_MSVCRT__setjmp(struct MSVCRT___JUMP_BUFFER *jmp)
	{
	jmp->Registration = (unsigned long)NtCurrentTeb()->Tib.ExceptionList;
	if (jmp->Registration == ~0UL)
	jmp->TryLevel = TRYLEVEL_END;
	else
	jmp->TryLevel = ((MSVCRT_EXCEPTION_FRAME*)jmp->Registration)->trylevel;

	TRACE("buf=%p ebx=%08lx esi=%08lx edi=%08lx ebp=%08lx esp=%08lx eip=%08lx frame=%08lx\n",
	jmp, jmp->Ebx, jmp->Esi, jmp->Edi, jmp->Ebp, jmp->Esp, jmp->Eip, jmp->Registration );
	return 0;
	}

	/*******************************************************************
	* _setjmp3 (MSVCRT.@)
	*/
	DEFINE_SETJMP_ENTRYPOINT( MSVCRT__setjmp3 )
	int CDECL __regs_MSVCRT__setjmp3(struct MSVCRT___JUMP_BUFFER *jmp, int nb_args, ...)
	{
	jmp->Cookie = MSVCRT_JMP_MAGIC;
	jmp->UnwindFunc = 0;
	jmp->Registration = (unsigned long)NtCurrentTeb()->Tib.ExceptionList;
	if (jmp->Registration == ~0UL)
	{
	jmp->TryLevel = TRYLEVEL_END;
	}
	else
	{
	int i;
	va_list args;

	va_start( args, nb_args );
	if (nb_args > 0) jmp->UnwindFunc = va_arg( args, unsigned long );
	if (nb_args > 1) jmp->TryLevel = va_arg( args, unsigned long );
	else jmp->TryLevel = ((MSVCRT_EXCEPTION_FRAME*)jmp->Registration)->trylevel;
	for (i = 0; i < 6 && i < nb_args - 2; i++)
	jmp->UnwindData[i] = va_arg( args, unsigned long );
	va_end( args );
	}

	TRACE("buf=%p ebx=%08lx esi=%08lx edi=%08lx ebp=%08lx esp=%08lx eip=%08lx frame=%08lx\n",
	jmp, jmp->Ebx, jmp->Esi, jmp->Edi, jmp->Ebp, jmp->Esp, jmp->Eip, jmp->Registration );
	return 0;
	}

	/*********************************************************************
	* longjmp (MSVCRT.@)
	*/
	int CDECL MSVCRT_longjmp(struct MSVCRT___JUMP_BUFFER *jmp, int retval)
	{
	unsigned long cur_frame = 0;

	TRACE("buf=%p ebx=%08lx esi=%08lx edi=%08lx ebp=%08lx esp=%08lx eip=%08lx frame=%08lx retval=%08x\n",
	jmp, jmp->Ebx, jmp->Esi, jmp->Edi, jmp->Ebp, jmp->Esp, jmp->Eip, jmp->Registration, retval );

	cur_frame=(unsigned long)NtCurrentTeb()->Tib.ExceptionList;
	TRACE("cur_frame=%lx\n",cur_frame);

	if (cur_frame != jmp->Registration)
	_global_unwind2((EXCEPTION_REGISTRATION_RECORD*)jmp->Registration);

	if (jmp->Registration)
	{
	if (!IsBadReadPtr(&jmp->Cookie, sizeof(long)) &&
	jmp->Cookie == MSVCRT_JMP_MAGIC && jmp->UnwindFunc)
	{
	MSVCRT_unwind_function unwind_func;

	unwind_func=(MSVCRT_unwind_function)jmp->UnwindFunc;
	unwind_func(jmp);
	}
	else
	msvcrt_local_unwind2((MSVCRT_EXCEPTION_FRAME*)jmp->Registration,
	jmp->TryLevel, (void *)jmp->Ebp);
	}

	if (!retval)
	retval = 1;

	longjmp_set_regs( jmp, retval );
	}

	/*********************************************************************
	* _seh_longjmp_unwind (MSVCRT.@)
	*/
	void __stdcall _seh_longjmp_unwind(struct MSVCRT___JUMP_BUFFER *jmp)
	{
	msvcrt_local_unwind2( (MSVCRT_EXCEPTION_FRAME )jmp->Registration, jmp->TryLevel, (void )jmp->Ebp );
	}
	#endif /* i386 */

	static MSVCRT___sighandler_t sighandlers[MSVCRT_NSIG] = { MSVCRT_SIG_DFL };

	static BOOL WINAPI msvcrt_console_handler(DWORD ctrlType)
	{
	BOOL ret = FALSE;

	switch (ctrlType)
	{
	case CTRL_C_EVENT:
	if (sighandlers[MSVCRT_SIGINT])
	{
	if (sighandlers[MSVCRT_SIGINT] != MSVCRT_SIG_IGN)
	sighandlers[MSVCRT_SIGINT](MSVCRT_SIGINT);
	ret = TRUE;
	}
	break;
	}
	return ret;
	}

	typedef void (*float_handler)(int, int);

	/* The exception codes are actually NTSTATUS values */
	static const struct
	{
	NTSTATUS status;
	int signal;
	} float_exception_map[] = {
	{ EXCEPTION_FLT_DENORMAL_OPERAND, _FPE_DENORMAL },
	{ EXCEPTION_FLT_DIVIDE_BY_ZERO, _FPE_ZERODIVIDE },
	{ EXCEPTION_FLT_INEXACT_RESULT, _FPE_INEXACT },
	{ EXCEPTION_FLT_INVALID_OPERATION, _FPE_INVALID },
	{ EXCEPTION_FLT_OVERFLOW, _FPE_OVERFLOW },
	{ EXCEPTION_FLT_STACK_CHECK, _FPE_STACKOVERFLOW },
	{ EXCEPTION_FLT_UNDERFLOW, _FPE_UNDERFLOW },
	};

	static LONG WINAPI msvcrt_exception_filter(struct _EXCEPTION_POINTERS *except)
	{
	LONG ret = EXCEPTION_CONTINUE_SEARCH;
	MSVCRT___sighandler_t handler;

	if (!except \|\| !except->ExceptionRecord)
	return EXCEPTION_CONTINUE_SEARCH;

	switch (except->ExceptionRecord->ExceptionCode)
	{
	case EXCEPTION_ACCESS_VIOLATION:
	if ((handler = sighandlers[MSVCRT_SIGSEGV]) != MSVCRT_SIG_DFL)
	{
	if (handler != MSVCRT_SIG_IGN)
	{
	sighandlers[MSVCRT_SIGSEGV] = MSVCRT_SIG_DFL;
	handler(MSVCRT_SIGSEGV);
	}
	ret = EXCEPTION_CONTINUE_EXECUTION;
	}
	break;
	/* According to
	* http://msdn.microsoft.com/library/en-us/vclib/html/_CRT_signal.asp
	* the FPE signal handler takes as a second argument the type of
	* floating point exception.
	*/
	case EXCEPTION_FLT_DENORMAL_OPERAND:
	case EXCEPTION_FLT_DIVIDE_BY_ZERO:
	case EXCEPTION_FLT_INEXACT_RESULT:
	case EXCEPTION_FLT_INVALID_OPERATION:
	case EXCEPTION_FLT_OVERFLOW:
	case EXCEPTION_FLT_STACK_CHECK:
	case EXCEPTION_FLT_UNDERFLOW:
	if ((handler = sighandlers[MSVCRT_SIGFPE]) != MSVCRT_SIG_DFL)
	{
	if (handler != MSVCRT_SIG_IGN)
	{
	int i, float_signal = _FPE_INVALID;

	sighandlers[MSVCRT_SIGFPE] = MSVCRT_SIG_DFL;
	for (i = 0; i < sizeof(float_exception_map) /
	sizeof(float_exception_map[0]); i++)
	{
	if (float_exception_map[i].status ==
	except->ExceptionRecord->ExceptionCode)
	{
	float_signal = float_exception_map[i].signal;
	break;
	}
	}
	((float_handler)handler)(MSVCRT_SIGFPE, float_signal);
	}
	ret = EXCEPTION_CONTINUE_EXECUTION;
	}
	break;
	case EXCEPTION_ILLEGAL_INSTRUCTION:
	if ((handler = sighandlers[MSVCRT_SIGILL]) != MSVCRT_SIG_DFL)
	{
	if (handler != MSVCRT_SIG_IGN)
	{
	sighandlers[MSVCRT_SIGILL] = MSVCRT_SIG_DFL;
	handler(MSVCRT_SIGILL);
	}
	ret = EXCEPTION_CONTINUE_EXECUTION;
	}
	break;
	}
	return ret;
	}

	void msvcrt_init_signals(void)
	{
	SetConsoleCtrlHandler(msvcrt_console_handler, TRUE);
	SetUnhandledExceptionFilter(msvcrt_exception_filter);
	}

	void msvcrt_free_signals(void)
	{
	SetConsoleCtrlHandler(msvcrt_console_handler, FALSE);
	SetUnhandledExceptionFilter(NULL);
	}

	/*********************************************************************
	* signal (MSVCRT.@)
	* MS signal handling is described here:
	* http://msdn.microsoft.com/library/en-us/vclib/html/_CRT_signal.asp
	* Some signals may never be generated except through an explicit call to
	* raise.
	*/
	MSVCRT___sighandler_t CDECL MSVCRT_signal(int sig, MSVCRT___sighandler_t func)
	{
	MSVCRT___sighandler_t ret = MSVCRT_SIG_ERR;

	TRACE("(%d, %p)\n", sig, func);

	if (func == MSVCRT_SIG_ERR) return MSVCRT_SIG_ERR;

	switch (sig)
	{
	/* Cases handled internally. Note SIGTERM is never generated by Windows,
	* so we effectively mask it.
	*/
	case MSVCRT_SIGABRT:
	case MSVCRT_SIGFPE:
	case MSVCRT_SIGILL:
	case MSVCRT_SIGSEGV:
	case MSVCRT_SIGINT:
	case MSVCRT_SIGTERM:
	ret = sighandlers[sig];
	sighandlers[sig] = func;
	break;
	default:
	ret = MSVCRT_SIG_ERR;
	}
	return ret;
	}

	/*********************************************************************
	* raise (MSVCRT.@)
	*/
	int CDECL MSVCRT_raise(int sig)
	{
	MSVCRT___sighandler_t handler;

	TRACE("(%d)\n", sig);

	switch (sig)
	{
	case MSVCRT_SIGABRT:
	case MSVCRT_SIGFPE:
	case MSVCRT_SIGILL:
	case MSVCRT_SIGSEGV:
	case MSVCRT_SIGINT:
	case MSVCRT_SIGTERM:
	handler = sighandlers[sig];
	if (handler == MSVCRT_SIG_DFL) MSVCRT__exit(3);
	if (handler != MSVCRT_SIG_IGN)
	{
	sighandlers[sig] = MSVCRT_SIG_DFL;
	if (sig == MSVCRT_SIGFPE)
	((float_handler)handler)(sig, _FPE_EXPLICITGEN);
	else
	handler(sig);
	}
	break;
	default:
	return -1;
	}
	return 0;
	}

	/*********************************************************************
	* _XcptFilter (MSVCRT.@)
	*/
	int CDECL _XcptFilter(NTSTATUS ex, PEXCEPTION_POINTERS ptr)
	{
	TRACE("(%08x,%p)\n", ex, ptr);
	/* I assume ptr->ExceptionRecord->ExceptionCode is the same as ex */
	return msvcrt_exception_filter(ptr);
	}