From c04f405172985f00ef831f9009c4389333ab272a Mon Sep 17 00:00:00 2001 From: Eric Pouech Date: Wed, 15 Aug 2001 17:34:07 +0000 Subject: [PATCH] Modified the debugger launching code so that only one instance of the debugger is created per process. --- win32/except.c | 233 +++++++++++++++++++++++++++++++------------------ 1 file changed, 147 insertions(+), 86 deletions(-) diff --git a/win32/except.c b/win32/except.c index 8aebe640260..71eebc67542 100644 --- a/win32/except.c +++ b/win32/except.c @@ -186,50 +186,22 @@ static int send_debug_event( EXCEPTION_RECORD *rec, int first_chance, CONTEXT *c return ret; } - -/******************************************************************* - * UnhandledExceptionFilter (KERNEL32.@) +/****************************************************************** + * start_debugger + * + * Does the effective debugger startup according to 'format' */ -DWORD WINAPI UnhandledExceptionFilter(PEXCEPTION_POINTERS epointers) +static BOOL start_debugger(PEXCEPTION_POINTERS epointers, HANDLE hEvent) { - 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 */ + PROCESS_INFORMATION info; + STARTUPINFOA startup; + char buffer[256]; + char format[256]; if (!RegOpenKeyA(HKEY_LOCAL_MACHINE, - "Software\\Microsoft\\Windows NT\\CurrentVersion\\AeDebug", - &hDbgConf)) { + "Software\\Microsoft\\Windows NT\\CurrentVersion\\AeDebug", &hDbgConf)) { DWORD type; DWORD count; @@ -249,61 +221,150 @@ DWORD WINAPI UnhandledExceptionFilter(PEXCEPTION_POINTERS epointers) } RegCloseKey(hDbgConf); } else { - /* format[0] = 0; */ - strcpy(format, "debugger/winedbg %ld %ld"); + /* try a default setup... */ + 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; - } - } + 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 FALSE; + } + } } - 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"); + TRACE("Starting debugger (fmt=%s)\n", format); + 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)) { + /* wait for debugger to come up... */ + WaitForSingleObject(hEvent, INFINITE); + return TRUE; } - - return ret; + 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()); + return FALSE; +} + +/****************************************************************** + * start_debugger_atomic + * + * starts the debugger is an atomic way: + * - either the debugger is not started and it is started + * - either the debugger has already been started by an other thread + * - either the debugger couldn't be started + * + * returns TRUE for the two first condition, FALSE for the last + */ +static int start_debugger_atomic(PEXCEPTION_POINTERS epointers) +{ + static HANDLE hRunOnce /* = 0 */; + + if (hRunOnce == 0) + { + OBJECT_ATTRIBUTES attr; + HANDLE hEvent; + + attr.Length = sizeof(attr); + attr.RootDirectory = 0; + attr.Attributes = OBJ_INHERIT; + attr.ObjectName = NULL; + attr.SecurityDescriptor = NULL; + attr.SecurityQualityOfService = NULL; + + /* ask for manual reset, so that once the debugger is started, every thread will be + * know it + */ + NtCreateEvent( &hEvent, EVENT_ALL_ACCESS, &attr, TRUE, FALSE ); + if (InterlockedCompareExchange( (LPLONG)&hRunOnce, hEvent, 0 ) == 0) + { + /* ok, our event has been set... we're the winning thread */ + BOOL ret = start_debugger( epointers, hRunOnce ); + DWORD tmp; + + if (!ret) + { + /* so that the other threads won't be stuck */ + NtSetEvent( hRunOnce, &tmp ); + } + return ret; + } + + /* someone beat us here... */ + CloseHandle( hEvent ); + } + + /* and wait for the winner to have actually created the debugger */ + WaitForSingleObject( hRunOnce, INFINITE ); + /* in fact, here, we only know that someone has tried to start the debugger, we'll know + * by reposting the exception if it has actually attached to the current process + */ + return TRUE; +} + + +/******************************************************************* + * UnhandledExceptionFilter (KERNEL32.@) + */ +DWORD WINAPI UnhandledExceptionFilter(PEXCEPTION_POINTERS epointers) +{ + int status; + int loop = 0; + + for (loop = 0; loop <= 1; loop++) + { + /* 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 ); + } + /* second try, the debugger isn't present... */ + if (loop == 1) return EXCEPTION_EXECUTE_HANDLER; + break; + default: + FIXME("Unsupported yet debug continue value %d (please report)\n", status); + return EXCEPTION_EXECUTE_HANDLER; + } + + /* should only be there when loop == 0 */ + + if (top_filter) + { + DWORD ret = top_filter( epointers ); + if (ret != EXCEPTION_CONTINUE_SEARCH) return ret; + } + + /* FIXME: Should check the current error mode */ + + if (!start_debugger_atomic( epointers )) + return EXCEPTION_EXECUTE_HANDLER; + /* now that we should have a debugger attached, try to resend event */ + } + + return EXCEPTION_EXECUTE_HANDLER; }