mirror of https://github.com/python/cpython
1139 lines
28 KiB
C
1139 lines
28 KiB
C
|
|
/* Signal module -- many thanks to Lance Ellinghaus */
|
|
|
|
/* XXX Signals should be recorded per thread, now we have thread state. */
|
|
|
|
#include "Python.h"
|
|
|
|
#ifdef MS_WINDOWS
|
|
#include <Windows.h>
|
|
#ifdef HAVE_PROCESS_H
|
|
#include <process.h>
|
|
#endif
|
|
#endif
|
|
|
|
#ifdef HAVE_SIGNAL_H
|
|
#include <signal.h>
|
|
#endif
|
|
#ifdef HAVE_SYS_STAT_H
|
|
#include <sys/stat.h>
|
|
#endif
|
|
#ifdef HAVE_SYS_TIME_H
|
|
#include <sys/time.h>
|
|
#endif
|
|
|
|
#if defined(HAVE_PTHREAD_SIGMASK) && !defined(HAVE_BROKEN_PTHREAD_SIGMASK)
|
|
# define PYPTHREAD_SIGMASK
|
|
#endif
|
|
|
|
#if defined(PYPTHREAD_SIGMASK) && defined(HAVE_PTHREAD_H)
|
|
# include <pthread.h>
|
|
#endif
|
|
|
|
#ifndef SIG_ERR
|
|
#define SIG_ERR ((PyOS_sighandler_t)(-1))
|
|
#endif
|
|
|
|
#if defined(PYOS_OS2) && !defined(PYCC_GCC)
|
|
#define NSIG 12
|
|
#include <process.h>
|
|
#endif
|
|
|
|
#ifndef NSIG
|
|
# if defined(_NSIG)
|
|
# define NSIG _NSIG /* For BSD/SysV */
|
|
# elif defined(_SIGMAX)
|
|
# define NSIG (_SIGMAX + 1) /* For QNX */
|
|
# elif defined(SIGMAX)
|
|
# define NSIG (SIGMAX + 1) /* For djgpp */
|
|
# else
|
|
# define NSIG 64 /* Use a reasonable default value */
|
|
# endif
|
|
#endif
|
|
|
|
|
|
/*
|
|
NOTES ON THE INTERACTION BETWEEN SIGNALS AND THREADS
|
|
|
|
When threads are supported, we want the following semantics:
|
|
|
|
- only the main thread can set a signal handler
|
|
- any thread can get a signal handler
|
|
- signals are only delivered to the main thread
|
|
|
|
I.e. we don't support "synchronous signals" like SIGFPE (catching
|
|
this doesn't make much sense in Python anyway) nor do we support
|
|
signals as a means of inter-thread communication, since not all
|
|
thread implementations support that (at least our thread library
|
|
doesn't).
|
|
|
|
We still have the problem that in some implementations signals
|
|
generated by the keyboard (e.g. SIGINT) are delivered to all
|
|
threads (e.g. SGI), while in others (e.g. Solaris) such signals are
|
|
delivered to one random thread (an intermediate possibility would
|
|
be to deliver it to the main thread -- POSIX?). For now, we have
|
|
a working implementation that works in all three cases -- the
|
|
handler ignores signals if getpid() isn't the same as in the main
|
|
thread. XXX This is a hack.
|
|
|
|
GNU pth is a user-space threading library, and as such, all threads
|
|
run within the same process. In this case, if the currently running
|
|
thread is not the main_thread, send the signal to the main_thread.
|
|
*/
|
|
|
|
#ifdef WITH_THREAD
|
|
#include <sys/types.h> /* For pid_t */
|
|
#include "pythread.h"
|
|
static long main_thread;
|
|
static pid_t main_pid;
|
|
#endif
|
|
|
|
static struct {
|
|
int tripped;
|
|
PyObject *func;
|
|
} Handlers[NSIG];
|
|
|
|
static sig_atomic_t wakeup_fd = -1;
|
|
|
|
/* Speed up sigcheck() when none tripped */
|
|
static volatile sig_atomic_t is_tripped = 0;
|
|
|
|
static PyObject *DefaultHandler;
|
|
static PyObject *IgnoreHandler;
|
|
static PyObject *IntHandler;
|
|
|
|
/* On Solaris 8, gcc will produce a warning that the function
|
|
declaration is not a prototype. This is caused by the definition of
|
|
SIG_DFL as (void (*)())0; the correct declaration would have been
|
|
(void (*)(int))0. */
|
|
|
|
static PyOS_sighandler_t old_siginthandler = SIG_DFL;
|
|
|
|
#ifdef HAVE_GETITIMER
|
|
static PyObject *ItimerError;
|
|
|
|
/* auxiliary functions for setitimer/getitimer */
|
|
static void
|
|
timeval_from_double(double d, struct timeval *tv)
|
|
{
|
|
tv->tv_sec = floor(d);
|
|
tv->tv_usec = fmod(d, 1.0) * 1000000.0;
|
|
}
|
|
|
|
Py_LOCAL_INLINE(double)
|
|
double_from_timeval(struct timeval *tv)
|
|
{
|
|
return tv->tv_sec + (double)(tv->tv_usec / 1000000.0);
|
|
}
|
|
|
|
static PyObject *
|
|
itimer_retval(struct itimerval *iv)
|
|
{
|
|
PyObject *r, *v;
|
|
|
|
r = PyTuple_New(2);
|
|
if (r == NULL)
|
|
return NULL;
|
|
|
|
if(!(v = PyFloat_FromDouble(double_from_timeval(&iv->it_value)))) {
|
|
Py_DECREF(r);
|
|
return NULL;
|
|
}
|
|
|
|
PyTuple_SET_ITEM(r, 0, v);
|
|
|
|
if(!(v = PyFloat_FromDouble(double_from_timeval(&iv->it_interval)))) {
|
|
Py_DECREF(r);
|
|
return NULL;
|
|
}
|
|
|
|
PyTuple_SET_ITEM(r, 1, v);
|
|
|
|
return r;
|
|
}
|
|
#endif
|
|
|
|
static PyObject *
|
|
signal_default_int_handler(PyObject *self, PyObject *args)
|
|
{
|
|
PyErr_SetNone(PyExc_KeyboardInterrupt);
|
|
return NULL;
|
|
}
|
|
|
|
PyDoc_STRVAR(default_int_handler_doc,
|
|
"default_int_handler(...)\n\
|
|
\n\
|
|
The default handler for SIGINT installed by Python.\n\
|
|
It raises KeyboardInterrupt.");
|
|
|
|
|
|
static int
|
|
checksignals_witharg(void * unused)
|
|
{
|
|
return PyErr_CheckSignals();
|
|
}
|
|
|
|
static void
|
|
trip_signal(int sig_num)
|
|
{
|
|
Handlers[sig_num].tripped = 1;
|
|
if (is_tripped)
|
|
return;
|
|
/* Set is_tripped after setting .tripped, as it gets
|
|
cleared in PyErr_CheckSignals() before .tripped. */
|
|
is_tripped = 1;
|
|
Py_AddPendingCall(checksignals_witharg, NULL);
|
|
if (wakeup_fd != -1)
|
|
write(wakeup_fd, "\0", 1);
|
|
}
|
|
|
|
static void
|
|
signal_handler(int sig_num)
|
|
{
|
|
int save_errno = errno;
|
|
|
|
#if defined(WITH_THREAD) && defined(WITH_PTH)
|
|
if (PyThread_get_thread_ident() != main_thread) {
|
|
pth_raise(*(pth_t *) main_thread, sig_num);
|
|
}
|
|
else
|
|
#endif
|
|
{
|
|
#ifdef WITH_THREAD
|
|
/* See NOTES section above */
|
|
if (getpid() == main_pid)
|
|
#endif
|
|
{
|
|
trip_signal(sig_num);
|
|
}
|
|
|
|
#ifndef HAVE_SIGACTION
|
|
#ifdef SIGCHLD
|
|
/* To avoid infinite recursion, this signal remains
|
|
reset until explicit re-instated.
|
|
Don't clear the 'func' field as it is our pointer
|
|
to the Python handler... */
|
|
if (sig_num != SIGCHLD)
|
|
#endif
|
|
/* If the handler was not set up with sigaction, reinstall it. See
|
|
* Python/pythonrun.c for the implementation of PyOS_setsig which
|
|
* makes this true. See also issue8354. */
|
|
PyOS_setsig(sig_num, signal_handler);
|
|
#endif
|
|
}
|
|
|
|
/* Issue #10311: asynchronously executing signal handlers should not
|
|
mutate errno under the feet of unsuspecting C code. */
|
|
errno = save_errno;
|
|
}
|
|
|
|
|
|
#ifdef HAVE_ALARM
|
|
static PyObject *
|
|
signal_alarm(PyObject *self, PyObject *args)
|
|
{
|
|
int t;
|
|
if (!PyArg_ParseTuple(args, "i:alarm", &t))
|
|
return NULL;
|
|
/* alarm() returns the number of seconds remaining */
|
|
return PyLong_FromLong((long)alarm(t));
|
|
}
|
|
|
|
PyDoc_STRVAR(alarm_doc,
|
|
"alarm(seconds)\n\
|
|
\n\
|
|
Arrange for SIGALRM to arrive after the given number of seconds.");
|
|
#endif
|
|
|
|
#ifdef HAVE_PAUSE
|
|
static PyObject *
|
|
signal_pause(PyObject *self)
|
|
{
|
|
Py_BEGIN_ALLOW_THREADS
|
|
(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;
|
|
}
|
|
PyDoc_STRVAR(pause_doc,
|
|
"pause()\n\
|
|
\n\
|
|
Wait until a signal arrives.");
|
|
|
|
#endif
|
|
|
|
|
|
static PyObject *
|
|
signal_signal(PyObject *self, PyObject *args)
|
|
{
|
|
PyObject *obj;
|
|
int sig_num;
|
|
PyObject *old_handler;
|
|
void (*func)(int);
|
|
if (!PyArg_ParseTuple(args, "iO:signal", &sig_num, &obj))
|
|
return NULL;
|
|
#ifdef MS_WINDOWS
|
|
/* Validate that sig_num is one of the allowable signals */
|
|
switch (sig_num) {
|
|
case SIGABRT: break;
|
|
#ifdef SIGBREAK
|
|
/* Issue #10003: SIGBREAK is not documented as permitted, but works
|
|
and corresponds to CTRL_BREAK_EVENT. */
|
|
case SIGBREAK: break;
|
|
#endif
|
|
case SIGFPE: break;
|
|
case SIGILL: break;
|
|
case SIGINT: break;
|
|
case SIGSEGV: break;
|
|
case SIGTERM: break;
|
|
default:
|
|
PyErr_SetString(PyExc_ValueError, "invalid signal value");
|
|
return NULL;
|
|
}
|
|
#endif
|
|
#ifdef WITH_THREAD
|
|
if (PyThread_get_thread_ident() != main_thread) {
|
|
PyErr_SetString(PyExc_ValueError,
|
|
"signal only works in main thread");
|
|
return NULL;
|
|
}
|
|
#endif
|
|
if (sig_num < 1 || sig_num >= NSIG) {
|
|
PyErr_SetString(PyExc_ValueError,
|
|
"signal number out of range");
|
|
return NULL;
|
|
}
|
|
if (obj == IgnoreHandler)
|
|
func = SIG_IGN;
|
|
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 NULL;
|
|
}
|
|
else
|
|
func = signal_handler;
|
|
if (PyOS_setsig(sig_num, func) == SIG_ERR) {
|
|
PyErr_SetFromErrno(PyExc_RuntimeError);
|
|
return NULL;
|
|
}
|
|
old_handler = Handlers[sig_num].func;
|
|
Handlers[sig_num].tripped = 0;
|
|
Py_INCREF(obj);
|
|
Handlers[sig_num].func = obj;
|
|
return old_handler;
|
|
}
|
|
|
|
PyDoc_STRVAR(signal_doc,
|
|
"signal(sig, action) -> action\n\
|
|
\n\
|
|
Set the action for the given signal. The action can be SIG_DFL,\n\
|
|
SIG_IGN, or a callable Python object. The previous action is\n\
|
|
returned. See getsignal() for possible return values.\n\
|
|
\n\
|
|
*** IMPORTANT NOTICE ***\n\
|
|
A signal handler function is called with two arguments:\n\
|
|
the first is the signal number, the second is the interrupted stack frame.");
|
|
|
|
|
|
static PyObject *
|
|
signal_getsignal(PyObject *self, PyObject *args)
|
|
{
|
|
int sig_num;
|
|
PyObject *old_handler;
|
|
if (!PyArg_ParseTuple(args, "i:getsignal", &sig_num))
|
|
return NULL;
|
|
if (sig_num < 1 || sig_num >= NSIG) {
|
|
PyErr_SetString(PyExc_ValueError,
|
|
"signal number out of range");
|
|
return NULL;
|
|
}
|
|
old_handler = Handlers[sig_num].func;
|
|
Py_INCREF(old_handler);
|
|
return old_handler;
|
|
}
|
|
|
|
PyDoc_STRVAR(getsignal_doc,
|
|
"getsignal(sig) -> action\n\
|
|
\n\
|
|
Return the current action for the given signal. The return value can be:\n\
|
|
SIG_IGN -- if the signal is being ignored\n\
|
|
SIG_DFL -- if the default action for the signal is in effect\n\
|
|
None -- if an unknown handler is in effect\n\
|
|
anything else -- the callable Python object used as a handler");
|
|
|
|
#ifdef HAVE_SIGINTERRUPT
|
|
PyDoc_STRVAR(siginterrupt_doc,
|
|
"siginterrupt(sig, flag) -> None\n\
|
|
change system call restart behaviour: if flag is False, system calls\n\
|
|
will be restarted when interrupted by signal sig, else system calls\n\
|
|
will be interrupted.");
|
|
|
|
static PyObject *
|
|
signal_siginterrupt(PyObject *self, PyObject *args)
|
|
{
|
|
int sig_num;
|
|
int flag;
|
|
|
|
if (!PyArg_ParseTuple(args, "ii:siginterrupt", &sig_num, &flag))
|
|
return NULL;
|
|
if (sig_num < 1 || sig_num >= NSIG) {
|
|
PyErr_SetString(PyExc_ValueError,
|
|
"signal number out of range");
|
|
return NULL;
|
|
}
|
|
if (siginterrupt(sig_num, flag)<0) {
|
|
PyErr_SetFromErrno(PyExc_RuntimeError);
|
|
return NULL;
|
|
}
|
|
|
|
Py_INCREF(Py_None);
|
|
return Py_None;
|
|
}
|
|
|
|
#endif
|
|
|
|
static PyObject *
|
|
signal_set_wakeup_fd(PyObject *self, PyObject *args)
|
|
{
|
|
struct stat buf;
|
|
int fd, old_fd;
|
|
if (!PyArg_ParseTuple(args, "i:set_wakeup_fd", &fd))
|
|
return NULL;
|
|
#ifdef WITH_THREAD
|
|
if (PyThread_get_thread_ident() != main_thread) {
|
|
PyErr_SetString(PyExc_ValueError,
|
|
"set_wakeup_fd only works in main thread");
|
|
return NULL;
|
|
}
|
|
#endif
|
|
if (fd != -1 && fstat(fd, &buf) != 0) {
|
|
PyErr_SetString(PyExc_ValueError, "invalid fd");
|
|
return NULL;
|
|
}
|
|
old_fd = wakeup_fd;
|
|
wakeup_fd = fd;
|
|
return PyLong_FromLong(old_fd);
|
|
}
|
|
|
|
PyDoc_STRVAR(set_wakeup_fd_doc,
|
|
"set_wakeup_fd(fd) -> fd\n\
|
|
\n\
|
|
Sets the fd to be written to (with '\\0') when a signal\n\
|
|
comes in. A library can use this to wakeup select or poll.\n\
|
|
The previous fd is returned.\n\
|
|
\n\
|
|
The fd must be non-blocking.");
|
|
|
|
/* C API for the same, without all the error checking */
|
|
int
|
|
PySignal_SetWakeupFd(int fd)
|
|
{
|
|
int old_fd = wakeup_fd;
|
|
if (fd < 0)
|
|
fd = -1;
|
|
wakeup_fd = fd;
|
|
return old_fd;
|
|
}
|
|
|
|
|
|
#ifdef HAVE_SETITIMER
|
|
static PyObject *
|
|
signal_setitimer(PyObject *self, PyObject *args)
|
|
{
|
|
double first;
|
|
double interval = 0;
|
|
int which;
|
|
struct itimerval new, old;
|
|
|
|
if(!PyArg_ParseTuple(args, "id|d:setitimer", &which, &first, &interval))
|
|
return NULL;
|
|
|
|
timeval_from_double(first, &new.it_value);
|
|
timeval_from_double(interval, &new.it_interval);
|
|
/* Let OS check "which" value */
|
|
if (setitimer(which, &new, &old) != 0) {
|
|
PyErr_SetFromErrno(ItimerError);
|
|
return NULL;
|
|
}
|
|
|
|
return itimer_retval(&old);
|
|
}
|
|
|
|
PyDoc_STRVAR(setitimer_doc,
|
|
"setitimer(which, seconds[, interval])\n\
|
|
\n\
|
|
Sets given itimer (one of ITIMER_REAL, ITIMER_VIRTUAL\n\
|
|
or ITIMER_PROF) to fire after value seconds and after\n\
|
|
that every interval seconds.\n\
|
|
The itimer can be cleared by setting seconds to zero.\n\
|
|
\n\
|
|
Returns old values as a tuple: (delay, interval).");
|
|
#endif
|
|
|
|
|
|
#ifdef HAVE_GETITIMER
|
|
static PyObject *
|
|
signal_getitimer(PyObject *self, PyObject *args)
|
|
{
|
|
int which;
|
|
struct itimerval old;
|
|
|
|
if (!PyArg_ParseTuple(args, "i:getitimer", &which))
|
|
return NULL;
|
|
|
|
if (getitimer(which, &old) != 0) {
|
|
PyErr_SetFromErrno(ItimerError);
|
|
return NULL;
|
|
}
|
|
|
|
return itimer_retval(&old);
|
|
}
|
|
|
|
PyDoc_STRVAR(getitimer_doc,
|
|
"getitimer(which)\n\
|
|
\n\
|
|
Returns current value of given itimer.");
|
|
#endif
|
|
|
|
#ifdef PYPTHREAD_SIGMASK
|
|
/* Convert an iterable to a sigset.
|
|
Return 0 on success, return -1 and raise an exception on error. */
|
|
|
|
static int
|
|
iterable_to_sigset(PyObject *iterable, sigset_t *mask)
|
|
{
|
|
int result = -1;
|
|
PyObject *iterator, *item;
|
|
long signum;
|
|
int err;
|
|
|
|
sigemptyset(mask);
|
|
|
|
iterator = PyObject_GetIter(iterable);
|
|
if (iterator == NULL)
|
|
goto error;
|
|
|
|
while (1)
|
|
{
|
|
item = PyIter_Next(iterator);
|
|
if (item == NULL) {
|
|
if (PyErr_Occurred())
|
|
goto error;
|
|
else
|
|
break;
|
|
}
|
|
|
|
signum = PyLong_AsLong(item);
|
|
Py_DECREF(item);
|
|
if (signum == -1 && PyErr_Occurred())
|
|
goto error;
|
|
if (0 < signum && signum < NSIG)
|
|
err = sigaddset(mask, (int)signum);
|
|
else
|
|
err = 1;
|
|
if (err) {
|
|
PyErr_Format(PyExc_ValueError,
|
|
"signal number %ld out of range", signum);
|
|
goto error;
|
|
}
|
|
}
|
|
result = 0;
|
|
|
|
error:
|
|
Py_XDECREF(iterator);
|
|
return result;
|
|
}
|
|
|
|
static PyObject *
|
|
signal_pthread_sigmask(PyObject *self, PyObject *args)
|
|
{
|
|
int how, sig;
|
|
PyObject *signals, *result, *signum;
|
|
sigset_t mask, previous;
|
|
int err;
|
|
|
|
if (!PyArg_ParseTuple(args, "iO:pthread_sigmask", &how, &signals))
|
|
return NULL;
|
|
|
|
if (iterable_to_sigset(signals, &mask))
|
|
return NULL;
|
|
|
|
err = pthread_sigmask(how, &mask, &previous);
|
|
if (err != 0) {
|
|
errno = err;
|
|
PyErr_SetFromErrno(PyExc_RuntimeError);
|
|
return NULL;
|
|
}
|
|
|
|
result = PyList_New(0);
|
|
if (result == NULL)
|
|
return NULL;
|
|
|
|
for (sig = 1; sig < NSIG; sig++) {
|
|
if (sigismember(&previous, sig) != 1)
|
|
continue;
|
|
|
|
/* Handle the case where it is a member by adding the signal to
|
|
the result list. Ignore the other cases because they mean the
|
|
signal isn't a member of the mask or the signal was invalid,
|
|
and an invalid signal must have been our fault in constructing
|
|
the loop boundaries. */
|
|
signum = PyLong_FromLong(sig);
|
|
if (signum == NULL) {
|
|
Py_DECREF(result);
|
|
return NULL;
|
|
}
|
|
if (PyList_Append(result, signum) == -1) {
|
|
Py_DECREF(signum);
|
|
Py_DECREF(result);
|
|
return NULL;
|
|
}
|
|
Py_DECREF(signum);
|
|
}
|
|
return result;
|
|
}
|
|
|
|
PyDoc_STRVAR(signal_pthread_sigmask_doc,
|
|
"pthread_sigmask(how, mask) -> old mask\n\
|
|
\n\
|
|
Fetch and/or change the signal mask of the calling thread.");
|
|
#endif /* #ifdef PYPTHREAD_SIGMASK */
|
|
|
|
|
|
/* List of functions defined in the module */
|
|
static PyMethodDef signal_methods[] = {
|
|
#ifdef HAVE_ALARM
|
|
{"alarm", signal_alarm, METH_VARARGS, alarm_doc},
|
|
#endif
|
|
#ifdef HAVE_SETITIMER
|
|
{"setitimer", signal_setitimer, METH_VARARGS, setitimer_doc},
|
|
#endif
|
|
#ifdef HAVE_GETITIMER
|
|
{"getitimer", signal_getitimer, METH_VARARGS, getitimer_doc},
|
|
#endif
|
|
{"signal", signal_signal, METH_VARARGS, signal_doc},
|
|
{"getsignal", signal_getsignal, METH_VARARGS, getsignal_doc},
|
|
{"set_wakeup_fd", signal_set_wakeup_fd, METH_VARARGS, set_wakeup_fd_doc},
|
|
#ifdef HAVE_SIGINTERRUPT
|
|
{"siginterrupt", signal_siginterrupt, METH_VARARGS, siginterrupt_doc},
|
|
#endif
|
|
#ifdef HAVE_PAUSE
|
|
{"pause", (PyCFunction)signal_pause,
|
|
METH_NOARGS, pause_doc},
|
|
#endif
|
|
{"default_int_handler", signal_default_int_handler,
|
|
METH_VARARGS, default_int_handler_doc},
|
|
#ifdef PYPTHREAD_SIGMASK
|
|
{"pthread_sigmask", (PyCFunction)signal_pthread_sigmask,
|
|
METH_VARARGS, signal_pthread_sigmask_doc},
|
|
#endif
|
|
{NULL, NULL} /* sentinel */
|
|
};
|
|
|
|
|
|
PyDoc_STRVAR(module_doc,
|
|
"This module provides mechanisms to use signal handlers in Python.\n\
|
|
\n\
|
|
Functions:\n\
|
|
\n\
|
|
alarm() -- cause SIGALRM after a specified time [Unix only]\n\
|
|
setitimer() -- cause a signal (described below) after a specified\n\
|
|
float time and the timer may restart then [Unix only]\n\
|
|
getitimer() -- get current value of timer [Unix only]\n\
|
|
signal() -- set the action for a given signal\n\
|
|
getsignal() -- get the signal action for a given signal\n\
|
|
pause() -- wait until a signal arrives [Unix only]\n\
|
|
default_int_handler() -- default SIGINT handler\n\
|
|
\n\
|
|
signal constants:\n\
|
|
SIG_DFL -- used to refer to the system default handler\n\
|
|
SIG_IGN -- used to ignore the signal\n\
|
|
NSIG -- number of defined signals\n\
|
|
SIGINT, SIGTERM, etc. -- signal numbers\n\
|
|
\n\
|
|
itimer constants:\n\
|
|
ITIMER_REAL -- decrements in real time, and delivers SIGALRM upon\n\
|
|
expiration\n\
|
|
ITIMER_VIRTUAL -- decrements only when the process is executing,\n\
|
|
and delivers SIGVTALRM upon expiration\n\
|
|
ITIMER_PROF -- decrements both when the process is executing and\n\
|
|
when the system is executing on behalf of the process.\n\
|
|
Coupled with ITIMER_VIRTUAL, this timer is usually\n\
|
|
used to profile the time spent by the application\n\
|
|
in user and kernel space. SIGPROF is delivered upon\n\
|
|
expiration.\n\
|
|
\n\n\
|
|
*** IMPORTANT NOTICE ***\n\
|
|
A signal handler function is called with two arguments:\n\
|
|
the first is the signal number, the second is the interrupted stack frame.");
|
|
|
|
static struct PyModuleDef signalmodule = {
|
|
PyModuleDef_HEAD_INIT,
|
|
"signal",
|
|
module_doc,
|
|
-1,
|
|
signal_methods,
|
|
NULL,
|
|
NULL,
|
|
NULL,
|
|
NULL
|
|
};
|
|
|
|
PyMODINIT_FUNC
|
|
PyInit_signal(void)
|
|
{
|
|
PyObject *m, *d, *x;
|
|
int i;
|
|
|
|
#ifdef WITH_THREAD
|
|
main_thread = PyThread_get_thread_ident();
|
|
main_pid = getpid();
|
|
#endif
|
|
|
|
/* Create the module and add the functions */
|
|
m = PyModule_Create(&signalmodule);
|
|
if (m == NULL)
|
|
return NULL;
|
|
|
|
/* Add some symbolic constants to the module */
|
|
d = PyModule_GetDict(m);
|
|
|
|
x = DefaultHandler = PyLong_FromVoidPtr((void *)SIG_DFL);
|
|
if (!x || PyDict_SetItemString(d, "SIG_DFL", x) < 0)
|
|
goto finally;
|
|
|
|
x = IgnoreHandler = PyLong_FromVoidPtr((void *)SIG_IGN);
|
|
if (!x || PyDict_SetItemString(d, "SIG_IGN", x) < 0)
|
|
goto finally;
|
|
|
|
x = PyLong_FromLong((long)NSIG);
|
|
if (!x || PyDict_SetItemString(d, "NSIG", x) < 0)
|
|
goto finally;
|
|
Py_DECREF(x);
|
|
|
|
#ifdef SIG_BLOCK
|
|
x = PyLong_FromLong(SIG_BLOCK);
|
|
if (!x || PyDict_SetItemString(d, "SIG_BLOCK", x) < 0)
|
|
goto finally;
|
|
Py_DECREF(x);
|
|
#endif
|
|
|
|
#ifdef SIG_UNBLOCK
|
|
x = PyLong_FromLong(SIG_UNBLOCK);
|
|
if (!x || PyDict_SetItemString(d, "SIG_UNBLOCK", x) < 0)
|
|
goto finally;
|
|
Py_DECREF(x);
|
|
#endif
|
|
|
|
#ifdef SIG_SETMASK
|
|
x = PyLong_FromLong(SIG_SETMASK);
|
|
if (!x || PyDict_SetItemString(d, "SIG_SETMASK", x) < 0)
|
|
goto finally;
|
|
Py_DECREF(x);
|
|
#endif
|
|
|
|
x = IntHandler = PyDict_GetItemString(d, "default_int_handler");
|
|
if (!x)
|
|
goto finally;
|
|
Py_INCREF(IntHandler);
|
|
|
|
Handlers[0].tripped = 0;
|
|
for (i = 1; i < NSIG; i++) {
|
|
void (*t)(int);
|
|
t = PyOS_getsig(i);
|
|
Handlers[i].tripped = 0;
|
|
if (t == SIG_DFL)
|
|
Handlers[i].func = DefaultHandler;
|
|
else if (t == SIG_IGN)
|
|
Handlers[i].func = IgnoreHandler;
|
|
else
|
|
Handlers[i].func = Py_None; /* None of our business */
|
|
Py_INCREF(Handlers[i].func);
|
|
}
|
|
if (Handlers[SIGINT].func == DefaultHandler) {
|
|
/* Install default int handler */
|
|
Py_INCREF(IntHandler);
|
|
Py_DECREF(Handlers[SIGINT].func);
|
|
Handlers[SIGINT].func = IntHandler;
|
|
old_siginthandler = PyOS_setsig(SIGINT, signal_handler);
|
|
}
|
|
|
|
#ifdef SIGHUP
|
|
x = PyLong_FromLong(SIGHUP);
|
|
PyDict_SetItemString(d, "SIGHUP", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGINT
|
|
x = PyLong_FromLong(SIGINT);
|
|
PyDict_SetItemString(d, "SIGINT", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGBREAK
|
|
x = PyLong_FromLong(SIGBREAK);
|
|
PyDict_SetItemString(d, "SIGBREAK", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGQUIT
|
|
x = PyLong_FromLong(SIGQUIT);
|
|
PyDict_SetItemString(d, "SIGQUIT", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGILL
|
|
x = PyLong_FromLong(SIGILL);
|
|
PyDict_SetItemString(d, "SIGILL", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGTRAP
|
|
x = PyLong_FromLong(SIGTRAP);
|
|
PyDict_SetItemString(d, "SIGTRAP", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGIOT
|
|
x = PyLong_FromLong(SIGIOT);
|
|
PyDict_SetItemString(d, "SIGIOT", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGABRT
|
|
x = PyLong_FromLong(SIGABRT);
|
|
PyDict_SetItemString(d, "SIGABRT", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGEMT
|
|
x = PyLong_FromLong(SIGEMT);
|
|
PyDict_SetItemString(d, "SIGEMT", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGFPE
|
|
x = PyLong_FromLong(SIGFPE);
|
|
PyDict_SetItemString(d, "SIGFPE", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGKILL
|
|
x = PyLong_FromLong(SIGKILL);
|
|
PyDict_SetItemString(d, "SIGKILL", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGBUS
|
|
x = PyLong_FromLong(SIGBUS);
|
|
PyDict_SetItemString(d, "SIGBUS", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGSEGV
|
|
x = PyLong_FromLong(SIGSEGV);
|
|
PyDict_SetItemString(d, "SIGSEGV", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGSYS
|
|
x = PyLong_FromLong(SIGSYS);
|
|
PyDict_SetItemString(d, "SIGSYS", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGPIPE
|
|
x = PyLong_FromLong(SIGPIPE);
|
|
PyDict_SetItemString(d, "SIGPIPE", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGALRM
|
|
x = PyLong_FromLong(SIGALRM);
|
|
PyDict_SetItemString(d, "SIGALRM", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGTERM
|
|
x = PyLong_FromLong(SIGTERM);
|
|
PyDict_SetItemString(d, "SIGTERM", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGUSR1
|
|
x = PyLong_FromLong(SIGUSR1);
|
|
PyDict_SetItemString(d, "SIGUSR1", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGUSR2
|
|
x = PyLong_FromLong(SIGUSR2);
|
|
PyDict_SetItemString(d, "SIGUSR2", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGCLD
|
|
x = PyLong_FromLong(SIGCLD);
|
|
PyDict_SetItemString(d, "SIGCLD", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGCHLD
|
|
x = PyLong_FromLong(SIGCHLD);
|
|
PyDict_SetItemString(d, "SIGCHLD", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGPWR
|
|
x = PyLong_FromLong(SIGPWR);
|
|
PyDict_SetItemString(d, "SIGPWR", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGIO
|
|
x = PyLong_FromLong(SIGIO);
|
|
PyDict_SetItemString(d, "SIGIO", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGURG
|
|
x = PyLong_FromLong(SIGURG);
|
|
PyDict_SetItemString(d, "SIGURG", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGWINCH
|
|
x = PyLong_FromLong(SIGWINCH);
|
|
PyDict_SetItemString(d, "SIGWINCH", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGPOLL
|
|
x = PyLong_FromLong(SIGPOLL);
|
|
PyDict_SetItemString(d, "SIGPOLL", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGSTOP
|
|
x = PyLong_FromLong(SIGSTOP);
|
|
PyDict_SetItemString(d, "SIGSTOP", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGTSTP
|
|
x = PyLong_FromLong(SIGTSTP);
|
|
PyDict_SetItemString(d, "SIGTSTP", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGCONT
|
|
x = PyLong_FromLong(SIGCONT);
|
|
PyDict_SetItemString(d, "SIGCONT", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGTTIN
|
|
x = PyLong_FromLong(SIGTTIN);
|
|
PyDict_SetItemString(d, "SIGTTIN", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGTTOU
|
|
x = PyLong_FromLong(SIGTTOU);
|
|
PyDict_SetItemString(d, "SIGTTOU", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGVTALRM
|
|
x = PyLong_FromLong(SIGVTALRM);
|
|
PyDict_SetItemString(d, "SIGVTALRM", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGPROF
|
|
x = PyLong_FromLong(SIGPROF);
|
|
PyDict_SetItemString(d, "SIGPROF", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGXCPU
|
|
x = PyLong_FromLong(SIGXCPU);
|
|
PyDict_SetItemString(d, "SIGXCPU", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGXFSZ
|
|
x = PyLong_FromLong(SIGXFSZ);
|
|
PyDict_SetItemString(d, "SIGXFSZ", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGRTMIN
|
|
x = PyLong_FromLong(SIGRTMIN);
|
|
PyDict_SetItemString(d, "SIGRTMIN", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGRTMAX
|
|
x = PyLong_FromLong(SIGRTMAX);
|
|
PyDict_SetItemString(d, "SIGRTMAX", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
#ifdef SIGINFO
|
|
x = PyLong_FromLong(SIGINFO);
|
|
PyDict_SetItemString(d, "SIGINFO", x);
|
|
Py_XDECREF(x);
|
|
#endif
|
|
|
|
#ifdef ITIMER_REAL
|
|
x = PyLong_FromLong(ITIMER_REAL);
|
|
PyDict_SetItemString(d, "ITIMER_REAL", x);
|
|
Py_DECREF(x);
|
|
#endif
|
|
#ifdef ITIMER_VIRTUAL
|
|
x = PyLong_FromLong(ITIMER_VIRTUAL);
|
|
PyDict_SetItemString(d, "ITIMER_VIRTUAL", x);
|
|
Py_DECREF(x);
|
|
#endif
|
|
#ifdef ITIMER_PROF
|
|
x = PyLong_FromLong(ITIMER_PROF);
|
|
PyDict_SetItemString(d, "ITIMER_PROF", x);
|
|
Py_DECREF(x);
|
|
#endif
|
|
|
|
#if defined (HAVE_SETITIMER) || defined (HAVE_GETITIMER)
|
|
ItimerError = PyErr_NewException("signal.ItimerError",
|
|
PyExc_IOError, NULL);
|
|
if (ItimerError != NULL)
|
|
PyDict_SetItemString(d, "ItimerError", ItimerError);
|
|
#endif
|
|
|
|
#ifdef CTRL_C_EVENT
|
|
x = PyLong_FromLong(CTRL_C_EVENT);
|
|
PyDict_SetItemString(d, "CTRL_C_EVENT", x);
|
|
Py_DECREF(x);
|
|
#endif
|
|
|
|
#ifdef CTRL_BREAK_EVENT
|
|
x = PyLong_FromLong(CTRL_BREAK_EVENT);
|
|
PyDict_SetItemString(d, "CTRL_BREAK_EVENT", x);
|
|
Py_DECREF(x);
|
|
#endif
|
|
|
|
if (PyErr_Occurred()) {
|
|
Py_DECREF(m);
|
|
m = NULL;
|
|
}
|
|
|
|
finally:
|
|
return m;
|
|
}
|
|
|
|
static void
|
|
finisignal(void)
|
|
{
|
|
int i;
|
|
PyObject *func;
|
|
|
|
PyOS_setsig(SIGINT, old_siginthandler);
|
|
old_siginthandler = SIG_DFL;
|
|
|
|
for (i = 1; i < NSIG; i++) {
|
|
func = Handlers[i].func;
|
|
Handlers[i].tripped = 0;
|
|
Handlers[i].func = NULL;
|
|
if (i != SIGINT && func != NULL && func != Py_None &&
|
|
func != DefaultHandler && func != IgnoreHandler)
|
|
PyOS_setsig(i, SIG_DFL);
|
|
Py_XDECREF(func);
|
|
}
|
|
|
|
Py_XDECREF(IntHandler);
|
|
IntHandler = NULL;
|
|
Py_XDECREF(DefaultHandler);
|
|
DefaultHandler = NULL;
|
|
Py_XDECREF(IgnoreHandler);
|
|
IgnoreHandler = NULL;
|
|
}
|
|
|
|
|
|
/* Declared in pyerrors.h */
|
|
int
|
|
PyErr_CheckSignals(void)
|
|
{
|
|
int i;
|
|
PyObject *f;
|
|
|
|
if (!is_tripped)
|
|
return 0;
|
|
|
|
#ifdef WITH_THREAD
|
|
if (PyThread_get_thread_ident() != main_thread)
|
|
return 0;
|
|
#endif
|
|
|
|
/*
|
|
* The is_tripped variable is meant to speed up the calls to
|
|
* PyErr_CheckSignals (both directly or via pending calls) when no
|
|
* signal has arrived. This variable is set to 1 when a signal arrives
|
|
* and it is set to 0 here, when we know some signals arrived. This way
|
|
* we can run the registered handlers with no signals blocked.
|
|
*
|
|
* NOTE: with this approach we can have a situation where is_tripped is
|
|
* 1 but we have no more signals to handle (Handlers[i].tripped
|
|
* is 0 for every signal i). This won't do us any harm (except
|
|
* we're gonna spent some cycles for nothing). This happens when
|
|
* we receive a signal i after we zero is_tripped and before we
|
|
* check Handlers[i].tripped.
|
|
*/
|
|
is_tripped = 0;
|
|
|
|
if (!(f = (PyObject *)PyEval_GetFrame()))
|
|
f = Py_None;
|
|
|
|
for (i = 1; i < NSIG; i++) {
|
|
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)
|
|
return -1;
|
|
|
|
Py_DECREF(result);
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/* Replacements for intrcheck.c functionality
|
|
* Declared in pyerrors.h
|
|
*/
|
|
void
|
|
PyErr_SetInterrupt(void)
|
|
{
|
|
trip_signal(SIGINT);
|
|
}
|
|
|
|
void
|
|
PyOS_InitInterrupts(void)
|
|
{
|
|
PyObject *m = PyInit_signal();
|
|
if (m) {
|
|
_PyImport_FixupBuiltin(m, "signal");
|
|
Py_DECREF(m);
|
|
}
|
|
}
|
|
|
|
void
|
|
PyOS_FiniInterrupts(void)
|
|
{
|
|
finisignal();
|
|
}
|
|
|
|
int
|
|
PyOS_InterruptOccurred(void)
|
|
{
|
|
if (Handlers[SIGINT].tripped) {
|
|
#ifdef WITH_THREAD
|
|
if (PyThread_get_thread_ident() != main_thread)
|
|
return 0;
|
|
#endif
|
|
Handlers[SIGINT].tripped = 0;
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
void
|
|
PyOS_AfterFork(void)
|
|
{
|
|
#ifdef WITH_THREAD
|
|
_PyGILState_Reinit();
|
|
PyEval_ReInitThreads();
|
|
main_thread = PyThread_get_thread_ident();
|
|
main_pid = getpid();
|
|
_PyImport_ReInitLock();
|
|
PyThread_ReInitTLS();
|
|
#endif
|
|
}
|