/* * Win32 exception functions * * Copyright (c) 1996 Onno Hovers, (onno@stack.urc.tue.nl) * Copyright (c) 1999 Alexandre Julliard * * Notes: * What really happens behind the scenes of those new * __try{...}__except(..){....} and * __try{...}__finally{...} * statements is simply not documented by Microsoft. There could be different * reasons for this: * One reason could be that they try to hide the fact that exception * handling in Win32 looks almost the same as in OS/2 2.x. * Another reason could be that Microsoft does not want others to write * binary compatible implementations of the Win32 API (like us). * * Whatever the reason, THIS SUCKS!! Ensuring portability or future * compatibility may be valid reasons to keep some things undocumented. * But exception handling is so basic to Win32 that it should be * documented! * */ #include <stdio.h> #include "windef.h" #include "winerror.h" #include "ntddk.h" #include "wingdi.h" #include "winuser.h" #include "wine/exception.h" #include "thread.h" #include "stackframe.h" #include "server.h" #include "debugtools.h" DEFAULT_DEBUG_CHANNEL(seh); static PTOP_LEVEL_EXCEPTION_FILTER top_filter; typedef INT (WINAPI *MessageBoxA_funcptr)(HWND,LPCSTR,LPCSTR,UINT); typedef INT (WINAPI *MessageBoxW_funcptr)(HWND,LPCWSTR,LPCWSTR,UINT); /******************************************************************* * RaiseException (KERNEL32.@) */ void WINAPI RaiseException( DWORD code, DWORD flags, DWORD nbargs, const LPDWORD args ) { EXCEPTION_RECORD record; /* Compose an exception record */ record.ExceptionCode = code; record.ExceptionFlags = flags & EH_NONCONTINUABLE; record.ExceptionRecord = NULL; record.ExceptionAddress = RaiseException; if (nbargs && args) { if (nbargs > EXCEPTION_MAXIMUM_PARAMETERS) nbargs = EXCEPTION_MAXIMUM_PARAMETERS; record.NumberParameters = nbargs; memcpy( record.ExceptionInformation, args, nbargs * sizeof(*args) ); } else record.NumberParameters = 0; RtlRaiseException( &record ); } /******************************************************************* * format_exception_msg */ static int format_exception_msg( const EXCEPTION_POINTERS *ptr, char *buffer, int size ) { const EXCEPTION_RECORD *rec = ptr->ExceptionRecord; int len,len2; switch(rec->ExceptionCode) { case EXCEPTION_INT_DIVIDE_BY_ZERO: len = snprintf( buffer, size, "Unhandled division by zero" ); break; case EXCEPTION_INT_OVERFLOW: len = snprintf( buffer, size, "Unhandled overflow" ); break; case EXCEPTION_ARRAY_BOUNDS_EXCEEDED: len = snprintf( buffer, size, "Unhandled array bounds" ); break; case EXCEPTION_ILLEGAL_INSTRUCTION: len = snprintf( buffer, size, "Unhandled illegal instruction" ); break; case EXCEPTION_STACK_OVERFLOW: len = snprintf( buffer, size, "Unhandled stack overflow" ); break; case EXCEPTION_PRIV_INSTRUCTION: len = snprintf( buffer, size, "Unhandled priviledged instruction" ); break; case EXCEPTION_ACCESS_VIOLATION: if (rec->NumberParameters == 2) len = snprintf( buffer, size, "Unhandled page fault on %s access to 0x%08lx", rec->ExceptionInformation[0] ? "write" : "read", rec->ExceptionInformation[1]); else len = snprintf( buffer, size, "Unhandled page fault"); break; case EXCEPTION_DATATYPE_MISALIGNMENT: len = snprintf( buffer, size, "Unhandled alignment" ); break; case CONTROL_C_EXIT: len = snprintf( buffer, size, "Unhandled ^C"); break; case EXCEPTION_CRITICAL_SECTION_WAIT: len = snprintf( buffer, size, "Critical section %08lx wait failed", rec->ExceptionInformation[0]); break; case EXCEPTION_WINE_STUB: len = snprintf( buffer, size, "Unimplemented function %s.%s called", (char *)rec->ExceptionInformation[0], (char *)rec->ExceptionInformation[1] ); break; case EXCEPTION_VM86_INTx: len = snprintf( buffer, size, "Unhandled interrupt %02lx in vm86 mode", rec->ExceptionInformation[0]); break; case EXCEPTION_VM86_STI: len = snprintf( buffer, size, "Unhandled sti in vm86 mode"); break; case EXCEPTION_VM86_PICRETURN: len = snprintf( buffer, size, "Unhandled PIC return in vm86 mode"); break; default: len = snprintf( buffer, size, "Unhandled exception 0x%08lx", rec->ExceptionCode); break; } if ((len<0) || (len>=size)) return -1; #ifdef __i386__ if (ptr->ContextRecord->SegCs != __get_cs()) len2 = snprintf(buffer+len, size-len, " at address 0x%04lx:0x%08lx.\nDo you wish to debug it ?", ptr->ContextRecord->SegCs, (DWORD)ptr->ExceptionRecord->ExceptionAddress); else #endif len2 = snprintf(buffer+len, size-len, " at address 0x%08lx.\nDo you wish to debug it ?", (DWORD)ptr->ExceptionRecord->ExceptionAddress); if ((len2<0) || (len>=size-len)) return -1; return len+len2; } /********************************************************************** * send_debug_event * * Send an EXCEPTION_DEBUG_EVENT event to the debugger. */ static int send_debug_event( EXCEPTION_RECORD *rec, int first_chance, CONTEXT *context ) { int ret; HANDLE handle = 0; SERVER_START_VAR_REQ( queue_exception_event, sizeof(*rec) + sizeof(*context) ) { CONTEXT *context_ptr = server_data_ptr(req); EXCEPTION_RECORD *rec_ptr = (EXCEPTION_RECORD *)(context_ptr + 1); req->first = first_chance; *rec_ptr = *rec; *context_ptr = *context; if (!SERVER_CALL()) handle = req->handle; } SERVER_END_VAR_REQ; if (!handle) return 0; /* no debugger present or other error */ /* No need to wait on the handle since the process gets suspended * once the event is passed to the debugger, so when we get back * here the event has been continued already. */ SERVER_START_VAR_REQ( get_exception_status, sizeof(*context) ) { req->handle = handle; if (!SERVER_CALL()) *context = *(CONTEXT *)server_data_ptr(req); ret = req->status; } SERVER_END_VAR_REQ; NtClose( handle ); return ret; } /******************************************************************* * UnhandledExceptionFilter (KERNEL32.@) */ DWORD WINAPI UnhandledExceptionFilter(PEXCEPTION_POINTERS epointers) { char format[256]; char buffer[256]; HKEY hDbgConf; DWORD bAuto = FALSE; DWORD ret = EXCEPTION_EXECUTE_HANDLER; int status; /* send a last chance event to the debugger */ status = send_debug_event( epointers->ExceptionRecord, FALSE, epointers->ContextRecord ); switch (status) { case DBG_CONTINUE: return EXCEPTION_CONTINUE_EXECUTION; case DBG_EXCEPTION_NOT_HANDLED: TerminateProcess( GetCurrentProcess(), epointers->ExceptionRecord->ExceptionCode ); break; /* not reached */ case 0: /* no debugger is present */ if (epointers->ExceptionRecord->ExceptionCode == CONTROL_C_EXIT) { /* do not launch the debugger on ^C, simply terminate the process */ TerminateProcess( GetCurrentProcess(), 1 ); } break; default: FIXME("Unsupported yet debug continue value %d (please report)\n", status); } if (top_filter) { DWORD ret = top_filter( epointers ); if (ret != EXCEPTION_CONTINUE_SEARCH) return ret; } /* FIXME: Should check the current error mode */ if (!RegOpenKeyA(HKEY_LOCAL_MACHINE, "Software\\Microsoft\\Windows NT\\CurrentVersion\\AeDebug", &hDbgConf)) { DWORD type; DWORD count; count = sizeof(format); if (RegQueryValueExA(hDbgConf, "Debugger", 0, &type, format, &count)) format[0] = 0; count = sizeof(bAuto); if (RegQueryValueExA(hDbgConf, "Auto", 0, &type, (char*)&bAuto, &count)) bAuto = TRUE; else if (type == REG_SZ) { char autostr[10]; count = sizeof(autostr); if (!RegQueryValueExA(hDbgConf, "Auto", 0, &type, autostr, &count)) bAuto = atoi(autostr); } RegCloseKey(hDbgConf); } else { /* format[0] = 0; */ strcpy(format, "debugger/winedbg %ld %ld"); } if (!bAuto) { HMODULE mod = GetModuleHandleA( "user32.dll" ); MessageBoxA_funcptr pMessageBoxA = NULL; if (mod) pMessageBoxA = (MessageBoxA_funcptr)GetProcAddress( mod, "MessageBoxA" ); if (pMessageBoxA) { format_exception_msg( epointers, buffer, sizeof(buffer) ); if (pMessageBoxA( 0, buffer, "Exception raised", MB_YESNO | MB_ICONHAND ) == IDNO) { TRACE("Killing process\n"); return EXCEPTION_EXECUTE_HANDLER; } } } if (format[0]) { HANDLE hEvent; PROCESS_INFORMATION info; STARTUPINFOA startup; OBJECT_ATTRIBUTES attr; attr.Length = sizeof(attr); attr.RootDirectory = 0; attr.Attributes = OBJ_INHERIT; attr.ObjectName = NULL; attr.SecurityDescriptor = NULL; attr.SecurityQualityOfService = NULL; TRACE("Starting debugger (fmt=%s)\n", format); NtCreateEvent( &hEvent, EVENT_ALL_ACCESS, &attr, FALSE, FALSE ); sprintf(buffer, format, GetCurrentProcessId(), hEvent); memset(&startup, 0, sizeof(startup)); startup.cb = sizeof(startup); startup.dwFlags = STARTF_USESHOWWINDOW; startup.wShowWindow = SW_SHOWNORMAL; if (CreateProcessA(NULL, buffer, NULL, NULL, TRUE, 0, NULL, NULL, &startup, &info)) { WaitForSingleObject(hEvent, INFINITE); ret = EXCEPTION_CONTINUE_SEARCH; } else { ERR("Couldn't start debugger (%s) (%ld)\n" "Read the Wine Developers Guide on how to set up winedbg or another debugger\n", buffer, GetLastError()); } CloseHandle(hEvent); } else { ERR("No standard debugger defined in the registry => no debugging session\n"); } return ret; } /*********************************************************************** * SetUnhandledExceptionFilter (KERNEL32.@) */ LPTOP_LEVEL_EXCEPTION_FILTER WINAPI SetUnhandledExceptionFilter( LPTOP_LEVEL_EXCEPTION_FILTER filter ) { LPTOP_LEVEL_EXCEPTION_FILTER old = top_filter; top_filter = filter; return old; } /************************************************************************** * FatalAppExitA (KERNEL32.@) */ void WINAPI FatalAppExitA( UINT action, LPCSTR str ) { HMODULE mod = GetModuleHandleA( "user32.dll" ); MessageBoxA_funcptr pMessageBoxA = NULL; WARN("AppExit\n"); if (mod) pMessageBoxA = (MessageBoxA_funcptr)GetProcAddress( mod, "MessageBoxA" ); if (pMessageBoxA) pMessageBoxA( 0, str, NULL, MB_SYSTEMMODAL | MB_OK ); else ERR( "%s\n", debugstr_a(str) ); ExitProcess(0); } /************************************************************************** * FatalAppExitW (KERNEL32.@) */ void WINAPI FatalAppExitW( UINT action, LPCWSTR str ) { HMODULE mod = GetModuleHandleA( "user32.dll" ); MessageBoxW_funcptr pMessageBoxW = NULL; WARN("AppExit\n"); if (mod) pMessageBoxW = (MessageBoxW_funcptr)GetProcAddress( mod, "MessageBoxW" ); if (pMessageBoxW) pMessageBoxW( 0, str, NULL, MB_SYSTEMMODAL | MB_OK ); else ERR( "%s\n", debugstr_w(str) ); ExitProcess(0); }