2 * Win32 exception functions
4 * Copyright (c) 1996 Onno Hovers, (onno@stack.urc.tue.nl)
5 * Copyright (c) 1999 Alexandre Julliard
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with this library; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 * What really happens behind the scenes of those new
23 * __try{...}__except(..){....} and
24 * __try{...}__finally{...}
25 * statements is simply not documented by Microsoft. There could be different
27 * One reason could be that they try to hide the fact that exception
28 * handling in Win32 looks almost the same as in OS/2 2.x.
29 * Another reason could be that Microsoft does not want others to write
30 * binary compatible implementations of the Win32 API (like us).
32 * Whatever the reason, THIS SUCKS!! Ensuring portability or future
33 * compatibility may be valid reasons to keep some things undocumented.
34 * But exception handling is so basic to Win32 that it should be
45 #include "wine/exception.h"
46 #include "wine/library.h"
48 #include "stackframe.h"
49 #include "wine/server.h"
50 #include "wine/debug.h"
51 #include "msvcrt/excpt.h"
53 WINE_DEFAULT_DEBUG_CHANNEL(seh);
55 static PTOP_LEVEL_EXCEPTION_FILTER top_filter;
57 typedef INT (WINAPI *MessageBoxA_funcptr)(HWND,LPCSTR,LPCSTR,UINT);
58 typedef INT (WINAPI *MessageBoxW_funcptr)(HWND,LPCWSTR,LPCWSTR,UINT);
60 /*******************************************************************
61 * RaiseException (KERNEL32.@)
63 void WINAPI RaiseException( DWORD code, DWORD flags, DWORD nbargs, const LPDWORD args )
65 EXCEPTION_RECORD record;
67 /* Compose an exception record */
69 record.ExceptionCode = code;
70 record.ExceptionFlags = flags & EH_NONCONTINUABLE;
71 record.ExceptionRecord = NULL;
72 record.ExceptionAddress = RaiseException;
75 if (nbargs > EXCEPTION_MAXIMUM_PARAMETERS) nbargs = EXCEPTION_MAXIMUM_PARAMETERS;
76 record.NumberParameters = nbargs;
77 memcpy( record.ExceptionInformation, args, nbargs * sizeof(*args) );
79 else record.NumberParameters = 0;
81 RtlRaiseException( &record );
85 /*******************************************************************
86 * format_exception_msg
88 static int format_exception_msg( const EXCEPTION_POINTERS *ptr, char *buffer, int size )
90 const EXCEPTION_RECORD *rec = ptr->ExceptionRecord;
93 switch(rec->ExceptionCode)
95 case EXCEPTION_INT_DIVIDE_BY_ZERO:
96 len = snprintf( buffer, size, "Unhandled division by zero" );
98 case EXCEPTION_INT_OVERFLOW:
99 len = snprintf( buffer, size, "Unhandled overflow" );
101 case EXCEPTION_ARRAY_BOUNDS_EXCEEDED:
102 len = snprintf( buffer, size, "Unhandled array bounds" );
104 case EXCEPTION_ILLEGAL_INSTRUCTION:
105 len = snprintf( buffer, size, "Unhandled illegal instruction" );
107 case EXCEPTION_STACK_OVERFLOW:
108 len = snprintf( buffer, size, "Unhandled stack overflow" );
110 case EXCEPTION_PRIV_INSTRUCTION:
111 len = snprintf( buffer, size, "Unhandled privileged instruction" );
113 case EXCEPTION_ACCESS_VIOLATION:
114 if (rec->NumberParameters == 2)
115 len = snprintf( buffer, size, "Unhandled page fault on %s access to 0x%08lx",
116 rec->ExceptionInformation[0] ? "write" : "read",
117 rec->ExceptionInformation[1]);
119 len = snprintf( buffer, size, "Unhandled page fault");
121 case EXCEPTION_DATATYPE_MISALIGNMENT:
122 len = snprintf( buffer, size, "Unhandled alignment" );
125 len = snprintf( buffer, size, "Unhandled ^C");
127 case EXCEPTION_CRITICAL_SECTION_WAIT:
128 len = snprintf( buffer, size, "Critical section %08lx wait failed",
129 rec->ExceptionInformation[0]);
131 case EXCEPTION_WINE_STUB:
132 len = snprintf( buffer, size, "Unimplemented function %s.%s called",
133 (char *)rec->ExceptionInformation[0], (char *)rec->ExceptionInformation[1] );
135 case EXCEPTION_VM86_INTx:
136 len = snprintf( buffer, size, "Unhandled interrupt %02lx in vm86 mode",
137 rec->ExceptionInformation[0]);
139 case EXCEPTION_VM86_STI:
140 len = snprintf( buffer, size, "Unhandled sti in vm86 mode");
142 case EXCEPTION_VM86_PICRETURN:
143 len = snprintf( buffer, size, "Unhandled PIC return in vm86 mode");
146 len = snprintf( buffer, size, "Unhandled exception 0x%08lx", rec->ExceptionCode);
149 if ((len<0) || (len>=size))
152 if (ptr->ContextRecord->SegCs != wine_get_cs())
153 len2 = snprintf(buffer+len, size-len,
154 " at address 0x%04lx:0x%08lx.\nDo you wish to debug it ?",
155 ptr->ContextRecord->SegCs,
156 (DWORD)ptr->ExceptionRecord->ExceptionAddress);
159 len2 = snprintf(buffer+len, size-len,
160 " at address 0x%08lx.\nDo you wish to debug it ?",
161 (DWORD)ptr->ExceptionRecord->ExceptionAddress);
162 if ((len2<0) || (len>=size-len))
168 /**********************************************************************
171 * Send an EXCEPTION_DEBUG_EVENT event to the debugger.
173 static int send_debug_event( EXCEPTION_RECORD *rec, int first_chance, CONTEXT *context )
178 SERVER_START_REQ( queue_exception_event )
180 req->first = first_chance;
181 wine_server_add_data( req, context, sizeof(*context) );
182 wine_server_add_data( req, rec, sizeof(*rec) );
183 if (!wine_server_call(req)) handle = reply->handle;
186 if (!handle) return 0; /* no debugger present or other error */
188 /* No need to wait on the handle since the process gets suspended
189 * once the event is passed to the debugger, so when we get back
190 * here the event has been continued already.
192 SERVER_START_REQ( get_exception_status )
194 req->handle = handle;
195 wine_server_set_reply( req, context, sizeof(*context) );
196 wine_server_call( req );
204 /******************************************************************
207 * Does the effective debugger startup according to 'format'
209 static BOOL start_debugger(PEXCEPTION_POINTERS epointers, HANDLE hEvent)
213 PROCESS_INFORMATION info;
214 STARTUPINFOA startup;
215 char* cmdline = NULL;
220 MESSAGE("wine: Unhandled exception, starting debugger...\n");
222 if (!RegOpenKeyA(HKEY_LOCAL_MACHINE,
223 "Software\\Microsoft\\Windows NT\\CurrentVersion\\AeDebug", &hDbgConf)) {
228 if (!RegQueryValueExA(hDbgConf, "Debugger", 0, &type, NULL, &format_size)) {
229 format = HeapAlloc(GetProcessHeap(), 0, format_size);
230 RegQueryValueExA(hDbgConf, "Debugger", 0, &type, format, &format_size);
231 if (type==REG_EXPAND_SZ) {
234 /* Expand environment variable references */
235 format_size=ExpandEnvironmentStringsA(format,NULL,0);
236 tmp=HeapAlloc(GetProcessHeap(), 0, format_size);
237 ExpandEnvironmentStringsA(format,tmp,format_size);
238 HeapFree(GetProcessHeap(), 0, format);
243 count = sizeof(bAuto);
244 if (RegQueryValueExA(hDbgConf, "Auto", 0, &type, (char*)&bAuto, &count))
246 else if (type == REG_SZ)
249 count = sizeof(autostr);
250 if (!RegQueryValueExA(hDbgConf, "Auto", 0, &type, autostr, &count))
251 bAuto = atoi(autostr);
253 RegCloseKey(hDbgConf);
255 /* try a default setup... */
256 strcpy( format, "winedbg --debugmsg -all --auto %ld %ld" );
261 HMODULE mod = GetModuleHandleA( "user32.dll" );
262 MessageBoxA_funcptr pMessageBoxA = NULL;
264 if (mod) pMessageBoxA = (MessageBoxA_funcptr)GetProcAddress( mod, "MessageBoxA" );
268 format_exception_msg( epointers, buffer, sizeof(buffer) );
269 if (pMessageBoxA( 0, buffer, "Exception raised", MB_YESNO | MB_ICONHAND ) == IDNO)
271 TRACE("Killing process\n");
278 TRACE("Starting debugger (fmt=%s)\n", format);
279 cmdline=HeapAlloc(GetProcessHeap(), 0, format_size+2*20);
280 sprintf(cmdline, format, GetCurrentProcessId(), hEvent);
281 memset(&startup, 0, sizeof(startup));
282 startup.cb = sizeof(startup);
283 startup.dwFlags = STARTF_USESHOWWINDOW;
284 startup.wShowWindow = SW_SHOWNORMAL;
285 if (CreateProcessA(NULL, cmdline, NULL, NULL, TRUE, 0, NULL, NULL, &startup, &info)) {
286 /* wait for debugger to come up... */
287 WaitForSingleObject(hEvent, INFINITE);
294 ERR("Couldn't start debugger (%s) (%ld)\n"
295 "Read the Wine Developers Guide on how to set up winedbg or another debugger\n",
296 debugstr_a(cmdline), GetLastError());
300 HeapFree(GetProcessHeap(), 0, cmdline);
302 HeapFree(GetProcessHeap(), 0, format);
306 /******************************************************************
307 * start_debugger_atomic
309 * starts the debugger in an atomic way:
310 * - either the debugger is not started and it is started
311 * - or the debugger has already been started by another thread
312 * - or the debugger couldn't be started
314 * returns TRUE for the two first conditions, FALSE for the last
316 static int start_debugger_atomic(PEXCEPTION_POINTERS epointers)
318 static HANDLE hRunOnce /* = 0 */;
322 OBJECT_ATTRIBUTES attr;
325 attr.Length = sizeof(attr);
326 attr.RootDirectory = 0;
327 attr.Attributes = OBJ_INHERIT;
328 attr.ObjectName = NULL;
329 attr.SecurityDescriptor = NULL;
330 attr.SecurityQualityOfService = NULL;
332 /* ask for manual reset, so that once the debugger is started,
333 * every thread will know it */
334 NtCreateEvent( &hEvent, EVENT_ALL_ACCESS, &attr, TRUE, FALSE );
335 if (InterlockedCompareExchange( (LPLONG)&hRunOnce, hEvent, 0 ) == 0)
337 /* ok, our event has been set... we're the winning thread */
338 BOOL ret = start_debugger( epointers, hRunOnce );
343 /* so that the other threads won't be stuck */
344 NtSetEvent( hRunOnce, &tmp );
349 /* someone beat us here... */
350 CloseHandle( hEvent );
353 /* and wait for the winner to have actually created the debugger */
354 WaitForSingleObject( hRunOnce, INFINITE );
355 /* in fact, here, we only know that someone has tried to start the debugger,
356 * we'll know by reposting the exception if it has actually attached
357 * to the current process */
362 /*******************************************************************
363 * UnhandledExceptionFilter (KERNEL32.@)
365 DWORD WINAPI UnhandledExceptionFilter(PEXCEPTION_POINTERS epointers)
370 for (loop = 0; loop <= 1; loop++)
372 /* send a last chance event to the debugger */
373 status = send_debug_event( epointers->ExceptionRecord, FALSE, epointers->ContextRecord );
377 return EXCEPTION_CONTINUE_EXECUTION;
378 case DBG_EXCEPTION_NOT_HANDLED:
379 TerminateProcess( GetCurrentProcess(), epointers->ExceptionRecord->ExceptionCode );
380 break; /* not reached */
381 case 0: /* no debugger is present */
382 if (epointers->ExceptionRecord->ExceptionCode == CONTROL_C_EXIT)
384 /* do not launch the debugger on ^C, simply terminate the process */
385 TerminateProcess( GetCurrentProcess(), 1 );
387 /* second try, the debugger isn't present... */
388 if (loop == 1) return EXCEPTION_EXECUTE_HANDLER;
391 FIXME("Unsupported yet debug continue value %d (please report)\n", status);
392 return EXCEPTION_EXECUTE_HANDLER;
395 /* should only be there when loop == 0 */
399 DWORD ret = top_filter( epointers );
400 if (ret != EXCEPTION_CONTINUE_SEARCH) return ret;
403 /* FIXME: Should check the current error mode */
405 if (!start_debugger_atomic( epointers ))
406 return EXCEPTION_EXECUTE_HANDLER;
407 /* now that we should have a debugger attached, try to resend event */
410 return EXCEPTION_EXECUTE_HANDLER;
414 /***********************************************************************
415 * SetUnhandledExceptionFilter (KERNEL32.@)
417 LPTOP_LEVEL_EXCEPTION_FILTER WINAPI SetUnhandledExceptionFilter(
418 LPTOP_LEVEL_EXCEPTION_FILTER filter )
420 LPTOP_LEVEL_EXCEPTION_FILTER old = top_filter;
426 /**************************************************************************
427 * FatalAppExitA (KERNEL32.@)
429 void WINAPI FatalAppExitA( UINT action, LPCSTR str )
431 HMODULE mod = GetModuleHandleA( "user32.dll" );
432 MessageBoxA_funcptr pMessageBoxA = NULL;
436 if (mod) pMessageBoxA = (MessageBoxA_funcptr)GetProcAddress( mod, "MessageBoxA" );
437 if (pMessageBoxA) pMessageBoxA( 0, str, NULL, MB_SYSTEMMODAL | MB_OK );
438 else ERR( "%s\n", debugstr_a(str) );
443 /**************************************************************************
444 * FatalAppExitW (KERNEL32.@)
446 void WINAPI FatalAppExitW( UINT action, LPCWSTR str )
448 HMODULE mod = GetModuleHandleA( "user32.dll" );
449 MessageBoxW_funcptr pMessageBoxW = NULL;
453 if (mod) pMessageBoxW = (MessageBoxW_funcptr)GetProcAddress( mod, "MessageBoxW" );
454 if (pMessageBoxW) pMessageBoxW( 0, str, NULL, MB_SYSTEMMODAL | MB_OK );
455 else ERR( "%s\n", debugstr_w(str) );