reactos/sdk/lib/crt/except/except.c

302 lines
9.9 KiB
C

/*
* 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
*
* FIXME: Incomplete support for nested exceptions/try block cleanup.
*/
#include <precomp.h>
#include "excpt.h"
#include <wine/exception.h>
void CDECL _global_unwind2(EXCEPTION_REGISTRATION_RECORD* frame);
typedef void (__cdecl *MSVCRT_security_error_handler)(int, void *);
static MSVCRT_security_error_handler security_error_handler;
/* 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;
typedef struct
{
int gs_cookie_offset;
ULONG gs_cookie_xor;
int eh_cookie_offset;
ULONG eh_cookie_xor;
SCOPETABLE entries[1];
} SCOPETABLE_V4;
#ifdef __i386__
static const SCOPETABLE_V4 *get_scopetable_v4( MSVCRT_EXCEPTION_FRAME *frame, ULONG_PTR cookie )
{
return (const SCOPETABLE_V4 *)((ULONG_PTR)frame->scopetable ^ cookie);
}
#if defined(__GNUC__)
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;
}
#elif defined(_MSC_VER)
#pragma warning(push)
#pragma warning(disable:4731) // Don't complain about changing ebp
void __inline call_finally_block( void *code_block, void *base_ptr )
{
__asm
{
mov eax, code_block
mov ebp, base_ptr
call [eax]
}
}
int __inline call_filter( int (*func)(PEXCEPTION_POINTERS), void *arg, void *_ebp )
{
int _ret;
__asm
{
push ebp
mov eax, arg
push eax
mov ebp, _ebp
mov eax, func
call [eax]
mov _ret, eax
pop ebp
pop ebp
}
return _ret;
}
int __inline call_unwind_func( int (*func)(void), void *_ebp )
{
int _ret;
__asm
{
push ebp
push ebx
push esi
push edi
mov ebp, _ebp
call dword ptr [func]
mov _ret, eax
pop edi
pop esi
pop ebx
pop ebp
}
return _ret;
}
#pragma warning(pop)
#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;
}
void msvcrt_local_unwind4( ULONG *cookie, MSVCRT_EXCEPTION_FRAME* frame, int trylevel, void *ebp )
{
EXCEPTION_REGISTRATION_RECORD reg;
const SCOPETABLE_V4 *scopetable = get_scopetable_v4( frame, *cookie );
TRACE("(%p,%d,%d)\n",frame, frame->trylevel, trylevel);
/* Register a handler in case of a nested exception */
reg.Handler = (PEXCEPTION_ROUTINE)MSVCRT_nested_handler;
reg.Prev = NtCurrentTeb()->NtTib.ExceptionList;
__wine_push_frame(&reg);
while (frame->trylevel != -2 && frame->trylevel != trylevel)
{
int level = frame->trylevel;
frame->trylevel = scopetable->entries[level].previousTryLevel;
if (!scopetable->entries[level].lpfnFilter)
{
TRACE( "__try block cleanup level %d handler %p ebp %p\n",
level, scopetable->entries[level].lpfnHandler, ebp );
call_unwind_func( scopetable->entries[level].lpfnHandler, ebp );
}
}
__wine_pop_frame(&reg);
TRACE("unwound OK\n");
}
/*********************************************************************
* _except_handler4_common (MSVCRT.@)
*/
int CDECL _except_handler4_common( ULONG *cookie, void (*check_cookie)(void),
EXCEPTION_RECORD *rec, MSVCRT_EXCEPTION_FRAME *frame,
CONTEXT *context, EXCEPTION_REGISTRATION_RECORD **dispatcher )
{
int retval, trylevel;
EXCEPTION_POINTERS exceptPtrs;
const SCOPETABLE_V4 *scope_table = get_scopetable_v4( frame, *cookie );
TRACE( "exception %x flags=%x at %p handler=%p %p %p cookie=%x scope table=%p cookies=%d/%x,%d/%x\n",
rec->ExceptionCode, rec->ExceptionFlags, rec->ExceptionAddress,
frame->handler, context, dispatcher, *cookie, scope_table,
scope_table->gs_cookie_offset, scope_table->gs_cookie_xor,
scope_table->eh_cookie_offset, scope_table->eh_cookie_xor );
/* FIXME: no cookie validation yet */
if (rec->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND))
{
/* Unwinding the current frame */
msvcrt_local_unwind4( cookie, frame, -2, &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;
while (trylevel != -2)
{
TRACE( "level %d prev %d filter %p\n", trylevel,
scope_table->entries[trylevel].previousTryLevel,
scope_table->entries[trylevel].lpfnFilter );
if (scope_table->entries[trylevel].lpfnFilter)
{
retval = call_filter( scope_table->entries[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_unwind4( cookie, frame, trylevel, &frame->_ebp );
/* Set our trylevel to the enclosing block, and call the __finally
* code, which won't return
*/
frame->trylevel = scope_table->entries[trylevel].previousTryLevel;
TRACE("__finally block %p\n",scope_table->entries[trylevel].lpfnHandler);
call_finally_block(scope_table->entries[trylevel].lpfnHandler, &frame->_ebp);
ERR("Returned from __finally block - expect crash!\n");
}
}
trylevel = scope_table->entries[trylevel].previousTryLevel;
}
}
TRACE("reached -2, returning ExceptionContinueSearch\n");
return ExceptionContinueSearch;
}
/*******************************************************************
* _local_unwind4 (MSVCRT.@)
*/
void CDECL _local_unwind4( ULONG *cookie, MSVCRT_EXCEPTION_FRAME* frame, int trylevel )
{
msvcrt_local_unwind4( cookie, frame, trylevel, &frame->_ebp );
}
/*********************************************************************
* _seh_longjmp_unwind4 (MSVCRT.@)
*/
void __stdcall _seh_longjmp_unwind4(struct __JUMP_BUFFER *jmp)
{
msvcrt_local_unwind4( (void *)jmp->Cookie, (MSVCRT_EXCEPTION_FRAME *)jmp->Registration,
jmp->TryLevel, (void *)jmp->Ebp );
}
#endif
/******************************************************************
* __uncaught_exception
*/
BOOL CDECL __uncaught_exception(void)
{
return FALSE;
}
/* _set_security_error_handler - not exported in native msvcrt, added in msvcr70 */
MSVCRT_security_error_handler CDECL _set_security_error_handler(
MSVCRT_security_error_handler handler )
{
MSVCRT_security_error_handler old = security_error_handler;
TRACE("(%p)\n", handler);
security_error_handler = handler;
return old;
}