From 929711765e3f7b351997099276d9bf11113a8a46 Mon Sep 17 00:00:00 2001 From: Barry Warsaw Date: Fri, 3 Jan 1997 00:14:25 +0000 Subject: Several changes: - Conform to standard Python C coding styles. - All static symbols were renamed and shorted. - Eyeballed all return values and memory references. - Fixed a bug in signal.pause() so that exceptions raised in signal handlers are now properly caught after pause() returns. - Removed SIGCPU and SIGFSZ. We surmise that these were typos for the previously missing SIGXCPU and SIGXFSZ. --- Modules/signalmodule.c | 262 +++++++++++++++++++++++++++++-------------------- 1 file changed, 157 insertions(+), 105 deletions(-) diff --git a/Modules/signalmodule.c b/Modules/signalmodule.c index 5a91419..2802af7 100644 --- a/Modules/signalmodule.c +++ b/Modules/signalmodule.c @@ -49,6 +49,7 @@ PERFORMANCE OF THIS SOFTWARE. #endif + /* NOTES ON THE INTERACTION BETWEEN SIGNALS AND THREADS @@ -81,44 +82,39 @@ static long main_thread; static pid_t main_pid; #endif -struct PySignal_SignalArrayStruct { - int tripped; - PyObject *func; -}; +static struct { + int tripped; + PyObject *func; +} Handlers[NSIG]; + +static int is_tripped = 0; /* Speed up sigcheck() when none tripped */ -static struct PySignal_SignalArrayStruct PySignal_SignalHandlerArray[NSIG]; -static int PySignal_IsTripped = 0; /* Speed up sigcheck() when none tripped */ +static PyObject *DefaultHandler; +static PyObject *IgnoreHandler; +static PyObject *IntHandler; -static PyObject *PySignal_SignalDefaultHandler; -static PyObject *PySignal_SignalIgnoreHandler; -static PyObject *PySignal_DefaultIntHandler; + static PyObject * -PySignal_CDefaultIntHandler(self, arg) +signal_default_int_handler(self, arg) PyObject *self; PyObject *arg; { PyErr_SetNone(PyExc_KeyboardInterrupt); - return (PyObject *)NULL; -} - -void -PyErr_SetInterrupt() -{ - PySignal_IsTripped++; - PySignal_SignalHandlerArray[SIGINT].tripped = 1; + return NULL; } + static RETSIGTYPE -PySignal_Handler(sig_num) +signal_handler(sig_num) int sig_num; { #ifdef WITH_THREAD /* See NOTES section above */ if (getpid() == main_pid) { #endif - PySignal_IsTripped++; - PySignal_SignalHandlerArray[sig_num].tripped = 1; + is_tripped++; + Handlers[sig_num].tripped = 1; #ifdef WITH_THREAD } #endif @@ -131,19 +127,20 @@ PySignal_Handler(sig_num) return; } #endif - (void *)signal(sig_num, &PySignal_Handler); + (void *)signal(sig_num, &signal_handler); } + #ifndef DONT_HAVE_SIG_ALARM static PyObject * -PySignal_Alarm(self, args) +signal_alarm(self, args) PyObject *self; /* Not used */ PyObject *args; { int t; if (!PyArg_Parse(args, "i", &t)) - return (PyObject *)NULL; + return NULL; /* alarm() returns the number of seconds remaining */ return PyInt_FromLong(alarm(t)); } @@ -151,22 +148,30 @@ PySignal_Alarm(self, args) #ifndef DONT_HAVE_SIG_PAUSE static PyObject * -PySignal_Pause(self, args) +signal_pause(self, args) PyObject *self; /* Not used */ PyObject *args; { if (!PyArg_NoArgs(args)) return NULL; + Py_BEGIN_ALLOW_THREADS - pause(); + (void)pause(); Py_END_ALLOW_THREADS + /* make sure that any exceptions that got raised are propagated + * back into Python + */ + if (PyErr_CheckSignals()) + return NULL; + Py_INCREF(Py_None); return Py_None; } #endif + static PyObject * -PySignal_Signal(self, args) +signal_signal(self, args) PyObject *self; /* Not used */ PyObject *args; { @@ -175,76 +180,79 @@ PySignal_Signal(self, args) PyObject *old_handler; RETSIGTYPE (*func)(); if (!PyArg_Parse(args, "(iO)", &sig_num, &obj)) - return (PyObject *)NULL; + return NULL; #ifdef WITH_THREAD if (get_thread_ident() != main_thread) { PyErr_SetString(PyExc_ValueError, "signal only works in main thread"); - return (PyObject *)NULL; + return NULL; } #endif if (sig_num < 1 || sig_num >= NSIG) { PyErr_SetString(PyExc_ValueError, "signal number out of range"); - return (PyObject *)NULL; + return NULL; } - if (obj == PySignal_SignalIgnoreHandler) + if (obj == IgnoreHandler) func = SIG_IGN; - else if (obj == PySignal_SignalDefaultHandler) + else if (obj == DefaultHandler) func = SIG_DFL; else if (!PyCallable_Check(obj)) { PyErr_SetString(PyExc_TypeError, "signal handler must be signal.SIG_IGN, signal.SIG_DFL, or a callable object"); - return (PyObject *)NULL; + return NULL; } else - func = PySignal_Handler; + func = signal_handler; if (signal(sig_num, func) == SIG_ERR) { PyErr_SetFromErrno(PyExc_RuntimeError); - return (PyObject *)NULL; + return NULL; } - old_handler = PySignal_SignalHandlerArray[sig_num].func; - PySignal_SignalHandlerArray[sig_num].tripped = 0; + old_handler = Handlers[sig_num].func; + Handlers[sig_num].tripped = 0; Py_INCREF(obj); - PySignal_SignalHandlerArray[sig_num].func = obj; + Handlers[sig_num].func = obj; return old_handler; } + static PyObject * -PySignal_GetSignal(self, args) +signal_get_signal(self, args) PyObject *self; /* Not used */ PyObject *args; { int sig_num; PyObject *old_handler; if (!PyArg_Parse(args, "i", &sig_num)) - return (PyObject *)NULL; + return NULL; if (sig_num < 1 || sig_num >= NSIG) { PyErr_SetString(PyExc_ValueError, "signal number out of range"); - return (PyObject *)NULL; + return NULL; } - old_handler = PySignal_SignalHandlerArray[sig_num].func; + old_handler = Handlers[sig_num].func; Py_INCREF(old_handler); return old_handler; } + /* List of functions defined in the module */ - -static PyMethodDef PySignal_methods[] = { +static PyMethodDef signal_methods[] = { #ifndef DONT_HAVE_SIG_ALARM - {"alarm", PySignal_Alarm}, + {"alarm", signal_alarm}, #endif - {"signal", PySignal_Signal}, - {"getsignal", PySignal_GetSignal}, + {"signal", signal_signal}, + {"getsignal", signal_get_signal}, #ifndef DONT_HAVE_SIG_PAUSE - {"pause", PySignal_Pause}, + {"pause", signal_pause}, #endif - {"default_int_handler", PySignal_CDefaultIntHandler}, + {"default_int_handler", signal_default_int_handler}, {NULL, NULL} /* sentinel */ }; + + void initsignal() { @@ -257,20 +265,29 @@ initsignal() #endif /* Create the module and add the functions */ - m = Py_InitModule("signal", PySignal_methods); + m = Py_InitModule("signal", signal_methods); /* Add some symbolic constants to the module */ d = PyModule_GetDict(m); - PySignal_SignalDefaultHandler = PyInt_FromLong((long)SIG_DFL); - PyDict_SetItemString(d, "SIG_DFL", PySignal_SignalDefaultHandler); - PySignal_SignalIgnoreHandler = PyInt_FromLong((long)SIG_IGN); - PyDict_SetItemString(d, "SIG_IGN", PySignal_SignalIgnoreHandler); - PyDict_SetItemString(d, "NSIG", PyInt_FromLong((long)NSIG)); - PySignal_DefaultIntHandler = - PyDict_GetItemString(d, "default_int_handler"); + x = DefaultHandler = PyInt_FromLong((long)SIG_DFL); + if (!x || PyDict_SetItemString(d, "SIG_DFL", x) < 0) + goto finally; + Py_DECREF(x); + + x = IgnoreHandler = PyInt_FromLong((long)SIG_IGN); + if (!x || PyDict_SetItemString(d, "SIG_IGN", x) < 0) + goto finally; + + x = PyInt_FromLong((long)NSIG); + if (!x || PyDict_SetItemString(d, "NSIG", x) < 0) + goto finally; - PySignal_SignalHandlerArray[0].tripped = 0; + x = IntHandler = PyDict_GetItemString(d, "default_int_handler"); + if (!x) + goto finally; + + Handlers[0].tripped = 0; for (i = 1; i < NSIG; i++) { RETSIGTYPE (*t)(); #ifdef HAVE_SIGACTION @@ -281,231 +298,266 @@ initsignal() t = signal(i, SIG_IGN); signal(i, t); #endif - PySignal_SignalHandlerArray[i].tripped = 0; + Handlers[i].tripped = 0; if (t == SIG_DFL) - PySignal_SignalHandlerArray[i].func = - PySignal_SignalDefaultHandler; + Handlers[i].func = DefaultHandler; else if (t == SIG_IGN) - PySignal_SignalHandlerArray[i].func = - PySignal_SignalIgnoreHandler; + Handlers[i].func = IgnoreHandler; else - PySignal_SignalHandlerArray[i].func = - Py_None; /* None of our business */ - Py_INCREF(PySignal_SignalHandlerArray[i].func); + Handlers[i].func = Py_None; /* None of our business */ + Py_INCREF(Handlers[i].func); } - if (PySignal_SignalHandlerArray[SIGINT].func == - PySignal_SignalDefaultHandler) { + if (Handlers[SIGINT].func == DefaultHandler) { /* Install default int handler */ - Py_DECREF(PySignal_SignalHandlerArray[SIGINT].func); - PySignal_SignalHandlerArray[SIGINT].func = - PySignal_DefaultIntHandler; - Py_INCREF(PySignal_DefaultIntHandler); - signal(SIGINT, &PySignal_Handler); + Py_DECREF(Handlers[SIGINT].func); + Handlers[SIGINT].func = IntHandler; + Py_INCREF(IntHandler); + signal(SIGINT, &signal_handler); } #ifdef SIGHUP x = PyInt_FromLong(SIGHUP); PyDict_SetItemString(d, "SIGHUP", x); + Py_DECREF(x); #endif #ifdef SIGINT x = PyInt_FromLong(SIGINT); PyDict_SetItemString(d, "SIGINT", x); + Py_DECREF(x); #endif #ifdef SIGQUIT x = PyInt_FromLong(SIGQUIT); PyDict_SetItemString(d, "SIGQUIT", x); + Py_DECREF(x); #endif #ifdef SIGILL x = PyInt_FromLong(SIGILL); PyDict_SetItemString(d, "SIGILL", x); + Py_DECREF(x); #endif #ifdef SIGTRAP x = PyInt_FromLong(SIGTRAP); PyDict_SetItemString(d, "SIGTRAP", x); + Py_DECREF(x); #endif #ifdef SIGIOT x = PyInt_FromLong(SIGIOT); PyDict_SetItemString(d, "SIGIOT", x); + Py_DECREF(x); #endif #ifdef SIGABRT x = PyInt_FromLong(SIGABRT); PyDict_SetItemString(d, "SIGABRT", x); + Py_DECREF(x); #endif #ifdef SIGEMT x = PyInt_FromLong(SIGEMT); PyDict_SetItemString(d, "SIGEMT", x); + Py_DECREF(x); #endif #ifdef SIGFPE x = PyInt_FromLong(SIGFPE); PyDict_SetItemString(d, "SIGFPE", x); + Py_DECREF(x); #endif #ifdef SIGKILL x = PyInt_FromLong(SIGKILL); PyDict_SetItemString(d, "SIGKILL", x); + Py_DECREF(x); #endif #ifdef SIGBUS x = PyInt_FromLong(SIGBUS); PyDict_SetItemString(d, "SIGBUS", x); + Py_DECREF(x); #endif #ifdef SIGSEGV x = PyInt_FromLong(SIGSEGV); PyDict_SetItemString(d, "SIGSEGV", x); + Py_DECREF(x); #endif #ifdef SIGSYS x = PyInt_FromLong(SIGSYS); PyDict_SetItemString(d, "SIGSYS", x); + Py_DECREF(x); #endif #ifdef SIGPIPE x = PyInt_FromLong(SIGPIPE); PyDict_SetItemString(d, "SIGPIPE", x); + Py_DECREF(x); #endif #ifdef SIGALRM x = PyInt_FromLong(SIGALRM); PyDict_SetItemString(d, "SIGALRM", x); + Py_DECREF(x); #endif #ifdef SIGTERM x = PyInt_FromLong(SIGTERM); PyDict_SetItemString(d, "SIGTERM", x); + Py_DECREF(x); #endif #ifdef SIGUSR1 x = PyInt_FromLong(SIGUSR1); PyDict_SetItemString(d, "SIGUSR1", x); + Py_DECREF(x); #endif #ifdef SIGUSR2 x = PyInt_FromLong(SIGUSR2); PyDict_SetItemString(d, "SIGUSR2", x); + Py_DECREF(x); #endif #ifdef SIGCLD x = PyInt_FromLong(SIGCLD); PyDict_SetItemString(d, "SIGCLD", x); + Py_DECREF(x); #endif #ifdef SIGCHLD x = PyInt_FromLong(SIGCHLD); PyDict_SetItemString(d, "SIGCHLD", x); + Py_DECREF(x); #endif #ifdef SIGPWR x = PyInt_FromLong(SIGPWR); PyDict_SetItemString(d, "SIGPWR", x); + Py_DECREF(x); #endif #ifdef SIGIO x = PyInt_FromLong(SIGIO); PyDict_SetItemString(d, "SIGIO", x); + Py_DECREF(x); #endif #ifdef SIGURG x = PyInt_FromLong(SIGURG); PyDict_SetItemString(d, "SIGURG", x); + Py_DECREF(x); #endif #ifdef SIGWINCH x = PyInt_FromLong(SIGWINCH); PyDict_SetItemString(d, "SIGWINCH", x); + Py_DECREF(x); #endif #ifdef SIGPOLL x = PyInt_FromLong(SIGPOLL); PyDict_SetItemString(d, "SIGPOLL", x); + Py_DECREF(x); #endif #ifdef SIGSTOP x = PyInt_FromLong(SIGSTOP); PyDict_SetItemString(d, "SIGSTOP", x); + Py_DECREF(x); #endif #ifdef SIGTSTP x = PyInt_FromLong(SIGTSTP); PyDict_SetItemString(d, "SIGTSTP", x); + Py_DECREF(x); #endif #ifdef SIGCONT x = PyInt_FromLong(SIGCONT); PyDict_SetItemString(d, "SIGCONT", x); + Py_DECREF(x); #endif #ifdef SIGTTIN x = PyInt_FromLong(SIGTTIN); PyDict_SetItemString(d, "SIGTTIN", x); + Py_DECREF(x); #endif #ifdef SIGTTOU x = PyInt_FromLong(SIGTTOU); PyDict_SetItemString(d, "SIGTTOU", x); + Py_DECREF(x); #endif #ifdef SIGVTALRM x = PyInt_FromLong(SIGVTALRM); PyDict_SetItemString(d, "SIGVTALRM", x); + Py_DECREF(x); #endif #ifdef SIGPROF x = PyInt_FromLong(SIGPROF); PyDict_SetItemString(d, "SIGPROF", x); -#endif -#ifdef SIGCPU - x = PyInt_FromLong(SIGCPU); - PyDict_SetItemString(d, "SIGCPU", x); + Py_DECREF(x); #endif #ifdef SIGXCPU x = PyInt_FromLong(SIGXCPU); PyDict_SetItemString(d, "SIGXCPU", x); -#endif -#ifdef SIGFSZ - x = PyInt_FromLong(SIGFSZ); - PyDict_SetItemString(d, "SIGFSZ", x); + Py_DECREF(x); #endif #ifdef SIGXFSZ x = PyInt_FromLong(SIGXFSZ); PyDict_SetItemString(d, "SIGXFSZ", x); + Py_DECREF(x); #endif + if (!PyErr_Occurred()) + return; + /* Check for errors */ - if (PyErr_Occurred()) - Py_FatalError("can't initialize module signal"); + finally: + Py_FatalError("can't initialize module signal"); } + + +/* Declared in pyerrors.h */ int PyErr_CheckSignals() { int i; PyObject *f; - if (!PySignal_IsTripped) + + if (!is_tripped) return 0; #ifdef WITH_THREAD if (get_thread_ident() != main_thread) return 0; #endif - f = PyEval_GetFrame(); - if (f == (PyObject *)NULL) + if (!(f = PyEval_GetFrame())) f = Py_None; + for (i = 1; i < NSIG; i++) { - if (PySignal_SignalHandlerArray[i].tripped) { - PyObject *arglist, *result; - PySignal_SignalHandlerArray[i].tripped = 0; - arglist = Py_BuildValue("(iO)", i, f); - if (arglist == (PyObject *)NULL) - result = (PyObject *)NULL; - else { - result = PyEval_CallObject( - PySignal_SignalHandlerArray[i].func, arglist); + if (Handlers[i].tripped) { + PyObject *result = NULL; + PyObject *arglist = Py_BuildValue("(iO)", i, f); + Handlers[i].tripped = 0; + + if (arglist) { + result = PyEval_CallObject(Handlers[i].func, + arglist); Py_DECREF(arglist); } - if (result == (PyObject *)NULL) { + if (!result) return 1; - } else { - Py_DECREF(result); - } + + Py_DECREF(result); } } - PySignal_IsTripped = 0; + is_tripped = 0; return 0; } -/* Replacement for intrcheck.c functionality */ + +/* Replacements for intrcheck.c functionality + * Declared in pyerrors.h + */ +void +PyErr_SetInterrupt() +{ + is_tripped++; + Handlers[SIGINT].tripped = 1; +} void -PyOS_InitInterrupts () +PyOS_InitInterrupts() { initsignal(); } int -PyOS_InterruptOccurred () +PyOS_InterruptOccurred() { - if (PySignal_SignalHandlerArray[SIGINT].tripped) { + if (Handlers[SIGINT].tripped) { #ifdef WITH_THREAD if (get_thread_ident() != main_thread) return 0; #endif - PySignal_SignalHandlerArray[SIGINT].tripped = 0; + Handlers[SIGINT].tripped = 0; return 1; } return 0; -- cgit v0.12