mirror of
https://github.com/python/cpython.git
synced 2024-12-05 07:43:50 +08:00
ba251c2ae6
Also introduce a new C API ``PyErr_SetInterruptEx(int signum)``.
1962 lines
49 KiB
C
1962 lines
49 KiB
C
|
|
/* Signal module -- many thanks to Lance Ellinghaus */
|
|
|
|
/* XXX Signals should be recorded per thread, now we have thread state. */
|
|
|
|
#include "Python.h"
|
|
#include "pycore_atomic.h"
|
|
#include "pycore_call.h"
|
|
#include "pycore_ceval.h"
|
|
#include "pycore_pyerrors.h"
|
|
#include "pycore_pylifecycle.h"
|
|
#include "pycore_pystate.h" // _PyThreadState_GET()
|
|
|
|
#ifndef MS_WINDOWS
|
|
#include "posixmodule.h"
|
|
#endif
|
|
#ifdef MS_WINDOWS
|
|
#include "socketmodule.h" /* needed for SOCKET_T */
|
|
#endif
|
|
|
|
#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_SYSCALL_H
|
|
#include <sys/syscall.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
|
|
|
|
#include "clinic/signalmodule.c.h"
|
|
|
|
/*[clinic input]
|
|
module signal
|
|
[clinic start generated code]*/
|
|
/*[clinic end generated code: output=da39a3ee5e6b4b0d input=b0301a3bde5fe9d3]*/
|
|
|
|
/*[python input]
|
|
|
|
class sigset_t_converter(CConverter):
|
|
type = 'sigset_t'
|
|
converter = '_Py_Sigset_Converter'
|
|
|
|
[python start generated code]*/
|
|
/*[python end generated code: output=da39a3ee5e6b4b0d input=b5689d14466b6823]*/
|
|
|
|
/*
|
|
NOTES ON THE INTERACTION BETWEEN SIGNALS AND THREADS
|
|
|
|
We want the following semantics:
|
|
|
|
- only the main thread can set a signal handler
|
|
- only the main thread runs the signal handler
|
|
- signals can be delivered to any thread
|
|
- any thread can get a signal handler
|
|
|
|
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. On Linux, signals are delivered to
|
|
the main thread (unless the main thread is blocking the signal, for
|
|
example because it's already handling the same signal). Since we
|
|
allow signals to be delivered to any thread, this works fine. The
|
|
only oddity is that the thread executing the Python signal handler
|
|
may not be the thread that received the signal.
|
|
*/
|
|
|
|
static volatile struct {
|
|
_Py_atomic_int tripped;
|
|
/* func is atomic to ensure that PyErr_SetInterrupt is async-signal-safe
|
|
* (even though it would probably be otherwise, anyway).
|
|
*/
|
|
_Py_atomic_address func;
|
|
} Handlers[NSIG];
|
|
|
|
#ifdef MS_WINDOWS
|
|
#define INVALID_FD ((SOCKET_T)-1)
|
|
|
|
static volatile struct {
|
|
SOCKET_T fd;
|
|
int warn_on_full_buffer;
|
|
int use_send;
|
|
} wakeup = {.fd = INVALID_FD, .warn_on_full_buffer = 1, .use_send = 0};
|
|
#else
|
|
#define INVALID_FD (-1)
|
|
static volatile struct {
|
|
#ifdef __VXWORKS__
|
|
int fd;
|
|
#else
|
|
sig_atomic_t fd;
|
|
#endif
|
|
int warn_on_full_buffer;
|
|
} wakeup = {.fd = INVALID_FD, .warn_on_full_buffer = 1};
|
|
#endif
|
|
|
|
/* Speed up sigcheck() when none tripped */
|
|
static _Py_atomic_int is_tripped;
|
|
|
|
static PyObject *DefaultHandler;
|
|
static PyObject *IgnoreHandler;
|
|
|
|
#ifdef MS_WINDOWS
|
|
static HANDLE sigint_event = NULL;
|
|
#endif
|
|
|
|
#if defined(HAVE_GETITIMER) || defined(HAVE_SETITIMER)
|
|
static PyObject *ItimerError;
|
|
#endif
|
|
|
|
Py_LOCAL_INLINE(PyObject *)
|
|
get_handler(int i) {
|
|
return (PyObject *)_Py_atomic_load(&Handlers[i].func);
|
|
}
|
|
|
|
Py_LOCAL_INLINE(void)
|
|
SetHandler(int i, PyObject* func) {
|
|
_Py_atomic_store(&Handlers[i].func, (uintptr_t)func);
|
|
}
|
|
|
|
#ifdef HAVE_GETITIMER
|
|
/* auxiliary functions for setitimer */
|
|
static int
|
|
timeval_from_double(PyObject *obj, struct timeval *tv)
|
|
{
|
|
if (obj == NULL) {
|
|
tv->tv_sec = 0;
|
|
tv->tv_usec = 0;
|
|
return 0;
|
|
}
|
|
|
|
_PyTime_t t;
|
|
if (_PyTime_FromSecondsObject(&t, obj, _PyTime_ROUND_CEILING) < 0) {
|
|
return -1;
|
|
}
|
|
return _PyTime_AsTimeval(t, tv, _PyTime_ROUND_CEILING);
|
|
}
|
|
|
|
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
|
|
|
|
/*[clinic input]
|
|
signal.default_int_handler
|
|
signalnum: int
|
|
frame: object
|
|
/
|
|
|
|
The default handler for SIGINT installed by Python.
|
|
|
|
It raises KeyboardInterrupt.
|
|
[clinic start generated code]*/
|
|
|
|
static PyObject *
|
|
signal_default_int_handler_impl(PyObject *module, int signalnum,
|
|
PyObject *frame)
|
|
/*[clinic end generated code: output=bb11c2eb115ace4e input=efcd4a56a207acfd]*/
|
|
{
|
|
PyErr_SetNone(PyExc_KeyboardInterrupt);
|
|
return NULL;
|
|
}
|
|
|
|
|
|
static int
|
|
report_wakeup_write_error(void *data)
|
|
{
|
|
PyObject *exc, *val, *tb;
|
|
int save_errno = errno;
|
|
errno = (int) (intptr_t) data;
|
|
PyErr_Fetch(&exc, &val, &tb);
|
|
PyErr_SetFromErrno(PyExc_OSError);
|
|
PySys_WriteStderr("Exception ignored when trying to write to the "
|
|
"signal wakeup fd:\n");
|
|
PyErr_WriteUnraisable(NULL);
|
|
PyErr_Restore(exc, val, tb);
|
|
errno = save_errno;
|
|
return 0;
|
|
}
|
|
|
|
#ifdef MS_WINDOWS
|
|
static int
|
|
report_wakeup_send_error(void* data)
|
|
{
|
|
PyObject *exc, *val, *tb;
|
|
PyErr_Fetch(&exc, &val, &tb);
|
|
/* PyErr_SetExcFromWindowsErr() invokes FormatMessage() which
|
|
recognizes the error codes used by both GetLastError() and
|
|
WSAGetLastError */
|
|
PyErr_SetExcFromWindowsErr(PyExc_OSError, (int) (intptr_t) data);
|
|
PySys_WriteStderr("Exception ignored when trying to send to the "
|
|
"signal wakeup fd:\n");
|
|
PyErr_WriteUnraisable(NULL);
|
|
PyErr_Restore(exc, val, tb);
|
|
return 0;
|
|
}
|
|
#endif /* MS_WINDOWS */
|
|
|
|
static void
|
|
trip_signal(int sig_num)
|
|
{
|
|
_Py_atomic_store_relaxed(&Handlers[sig_num].tripped, 1);
|
|
|
|
/* Set is_tripped after setting .tripped, as it gets
|
|
cleared in PyErr_CheckSignals() before .tripped. */
|
|
_Py_atomic_store(&is_tripped, 1);
|
|
|
|
/* Signals are always handled by the main interpreter */
|
|
PyInterpreterState *interp = _PyRuntime.interpreters.main;
|
|
|
|
/* Notify ceval.c */
|
|
_PyEval_SignalReceived(interp);
|
|
|
|
/* And then write to the wakeup fd *after* setting all the globals and
|
|
doing the _PyEval_SignalReceived. We used to write to the wakeup fd
|
|
and then set the flag, but this allowed the following sequence of events
|
|
(especially on windows, where trip_signal may run in a new thread):
|
|
|
|
- main thread blocks on select([wakeup.fd], ...)
|
|
- signal arrives
|
|
- trip_signal writes to the wakeup fd
|
|
- the main thread wakes up
|
|
- the main thread checks the signal flags, sees that they're unset
|
|
- the main thread empties the wakeup fd
|
|
- the main thread goes back to sleep
|
|
- trip_signal sets the flags to request the Python-level signal handler
|
|
be run
|
|
- the main thread doesn't notice, because it's asleep
|
|
|
|
See bpo-30038 for more details.
|
|
*/
|
|
|
|
int fd;
|
|
#ifdef MS_WINDOWS
|
|
fd = Py_SAFE_DOWNCAST(wakeup.fd, SOCKET_T, int);
|
|
#else
|
|
fd = wakeup.fd;
|
|
#endif
|
|
|
|
if (fd != INVALID_FD) {
|
|
unsigned char byte = (unsigned char)sig_num;
|
|
#ifdef MS_WINDOWS
|
|
if (wakeup.use_send) {
|
|
Py_ssize_t rc = send(fd, &byte, 1, 0);
|
|
|
|
if (rc < 0) {
|
|
int last_error = GetLastError();
|
|
if (wakeup.warn_on_full_buffer ||
|
|
last_error != WSAEWOULDBLOCK)
|
|
{
|
|
/* _PyEval_AddPendingCall() isn't signal-safe, but we
|
|
still use it for this exceptional case. */
|
|
_PyEval_AddPendingCall(interp,
|
|
report_wakeup_send_error,
|
|
(void *)(intptr_t) last_error);
|
|
}
|
|
}
|
|
}
|
|
else
|
|
#endif
|
|
{
|
|
/* _Py_write_noraise() retries write() if write() is interrupted by
|
|
a signal (fails with EINTR). */
|
|
Py_ssize_t rc = _Py_write_noraise(fd, &byte, 1);
|
|
|
|
if (rc < 0) {
|
|
if (wakeup.warn_on_full_buffer ||
|
|
(errno != EWOULDBLOCK && errno != EAGAIN))
|
|
{
|
|
/* _PyEval_AddPendingCall() isn't signal-safe, but we
|
|
still use it for this exceptional case. */
|
|
_PyEval_AddPendingCall(interp,
|
|
report_wakeup_write_error,
|
|
(void *)(intptr_t)errno);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
static void
|
|
signal_handler(int sig_num)
|
|
{
|
|
int save_errno = errno;
|
|
|
|
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/pylifecycle.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 MS_WINDOWS
|
|
if (sig_num == SIGINT)
|
|
SetEvent(sigint_event);
|
|
#endif
|
|
}
|
|
|
|
|
|
#ifdef HAVE_ALARM
|
|
|
|
/*[clinic input]
|
|
signal.alarm -> long
|
|
|
|
seconds: int
|
|
/
|
|
|
|
Arrange for SIGALRM to arrive after the given number of seconds.
|
|
[clinic start generated code]*/
|
|
|
|
static long
|
|
signal_alarm_impl(PyObject *module, int seconds)
|
|
/*[clinic end generated code: output=144232290814c298 input=0d5e97e0e6f39e86]*/
|
|
{
|
|
/* alarm() returns the number of seconds remaining */
|
|
return (long)alarm(seconds);
|
|
}
|
|
|
|
#endif
|
|
|
|
#ifdef HAVE_PAUSE
|
|
|
|
/*[clinic input]
|
|
signal.pause
|
|
|
|
Wait until a signal arrives.
|
|
[clinic start generated code]*/
|
|
|
|
static PyObject *
|
|
signal_pause_impl(PyObject *module)
|
|
/*[clinic end generated code: output=391656788b3c3929 input=f03de0f875752062]*/
|
|
{
|
|
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_RETURN_NONE;
|
|
}
|
|
|
|
#endif
|
|
|
|
/*[clinic input]
|
|
signal.raise_signal
|
|
|
|
signalnum: int
|
|
/
|
|
|
|
Send a signal to the executing process.
|
|
[clinic start generated code]*/
|
|
|
|
static PyObject *
|
|
signal_raise_signal_impl(PyObject *module, int signalnum)
|
|
/*[clinic end generated code: output=e2b014220aa6111d input=e90c0f9a42358de6]*/
|
|
{
|
|
int err;
|
|
Py_BEGIN_ALLOW_THREADS
|
|
_Py_BEGIN_SUPPRESS_IPH
|
|
err = raise(signalnum);
|
|
_Py_END_SUPPRESS_IPH
|
|
Py_END_ALLOW_THREADS
|
|
|
|
if (err) {
|
|
return PyErr_SetFromErrno(PyExc_OSError);
|
|
}
|
|
Py_RETURN_NONE;
|
|
}
|
|
|
|
/*[clinic input]
|
|
signal.signal
|
|
|
|
signalnum: int
|
|
handler: object
|
|
/
|
|
|
|
Set the action for the given signal.
|
|
|
|
The action can be SIG_DFL, SIG_IGN, or a callable Python object.
|
|
The previous action is returned. See getsignal() for possible return values.
|
|
|
|
*** IMPORTANT NOTICE ***
|
|
A signal handler function is called with two arguments:
|
|
the first is the signal number, the second is the interrupted stack frame.
|
|
[clinic start generated code]*/
|
|
|
|
static PyObject *
|
|
signal_signal_impl(PyObject *module, int signalnum, PyObject *handler)
|
|
/*[clinic end generated code: output=b44cfda43780f3a1 input=deee84af5fa0432c]*/
|
|
{
|
|
PyObject *old_handler;
|
|
void (*func)(int);
|
|
#ifdef MS_WINDOWS
|
|
/* Validate that signalnum is one of the allowable signals */
|
|
switch (signalnum) {
|
|
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
|
|
|
|
PyThreadState *tstate = _PyThreadState_GET();
|
|
if (!_Py_ThreadCanHandleSignals(tstate->interp)) {
|
|
_PyErr_SetString(tstate, PyExc_ValueError,
|
|
"signal only works in main thread "
|
|
"of the main interpreter");
|
|
return NULL;
|
|
}
|
|
if (signalnum < 1 || signalnum >= NSIG) {
|
|
_PyErr_SetString(tstate, PyExc_ValueError,
|
|
"signal number out of range");
|
|
return NULL;
|
|
}
|
|
if (handler == IgnoreHandler) {
|
|
func = SIG_IGN;
|
|
}
|
|
else if (handler == DefaultHandler) {
|
|
func = SIG_DFL;
|
|
}
|
|
else if (!PyCallable_Check(handler)) {
|
|
_PyErr_SetString(tstate, PyExc_TypeError,
|
|
"signal handler must be signal.SIG_IGN, "
|
|
"signal.SIG_DFL, or a callable object");
|
|
return NULL;
|
|
}
|
|
else {
|
|
func = signal_handler;
|
|
}
|
|
|
|
/* Check for pending signals before changing signal handler */
|
|
if (_PyErr_CheckSignalsTstate(tstate)) {
|
|
return NULL;
|
|
}
|
|
if (PyOS_setsig(signalnum, func) == SIG_ERR) {
|
|
PyErr_SetFromErrno(PyExc_OSError);
|
|
return NULL;
|
|
}
|
|
|
|
old_handler = get_handler(signalnum);
|
|
SetHandler(signalnum, Py_NewRef(handler));
|
|
|
|
if (old_handler != NULL) {
|
|
return old_handler;
|
|
}
|
|
else {
|
|
Py_RETURN_NONE;
|
|
}
|
|
}
|
|
|
|
|
|
/*[clinic input]
|
|
signal.getsignal
|
|
|
|
signalnum: int
|
|
/
|
|
|
|
Return the current action for the given signal.
|
|
|
|
The return value can be:
|
|
SIG_IGN -- if the signal is being ignored
|
|
SIG_DFL -- if the default action for the signal is in effect
|
|
None -- if an unknown handler is in effect
|
|
anything else -- the callable Python object used as a handler
|
|
[clinic start generated code]*/
|
|
|
|
static PyObject *
|
|
signal_getsignal_impl(PyObject *module, int signalnum)
|
|
/*[clinic end generated code: output=35b3e0e796fd555e input=ac23a00f19dfa509]*/
|
|
{
|
|
PyObject *old_handler;
|
|
if (signalnum < 1 || signalnum >= NSIG) {
|
|
PyErr_SetString(PyExc_ValueError,
|
|
"signal number out of range");
|
|
return NULL;
|
|
}
|
|
old_handler = get_handler(signalnum);
|
|
if (old_handler != NULL) {
|
|
return Py_NewRef(old_handler);
|
|
}
|
|
else {
|
|
Py_RETURN_NONE;
|
|
}
|
|
}
|
|
|
|
|
|
/*[clinic input]
|
|
signal.strsignal
|
|
|
|
signalnum: int
|
|
/
|
|
|
|
Return the system description of the given signal.
|
|
|
|
The return values can be such as "Interrupt", "Segmentation fault", etc.
|
|
Returns None if the signal is not recognized.
|
|
[clinic start generated code]*/
|
|
|
|
static PyObject *
|
|
signal_strsignal_impl(PyObject *module, int signalnum)
|
|
/*[clinic end generated code: output=44e12e1e3b666261 input=b77914b03f856c74]*/
|
|
{
|
|
char *res;
|
|
|
|
if (signalnum < 1 || signalnum >= NSIG) {
|
|
PyErr_SetString(PyExc_ValueError,
|
|
"signal number out of range");
|
|
return NULL;
|
|
}
|
|
|
|
#ifndef HAVE_STRSIGNAL
|
|
switch (signalnum) {
|
|
/* Though being a UNIX, HP-UX does not provide strsignal(3). */
|
|
#ifndef MS_WINDOWS
|
|
case SIGHUP:
|
|
res = "Hangup";
|
|
break;
|
|
case SIGALRM:
|
|
res = "Alarm clock";
|
|
break;
|
|
case SIGPIPE:
|
|
res = "Broken pipe";
|
|
break;
|
|
case SIGQUIT:
|
|
res = "Quit";
|
|
break;
|
|
case SIGCHLD:
|
|
res = "Child exited";
|
|
break;
|
|
#endif
|
|
/* Custom redefinition of POSIX signals allowed on Windows. */
|
|
case SIGINT:
|
|
res = "Interrupt";
|
|
break;
|
|
case SIGILL:
|
|
res = "Illegal instruction";
|
|
break;
|
|
case SIGABRT:
|
|
res = "Aborted";
|
|
break;
|
|
case SIGFPE:
|
|
res = "Floating point exception";
|
|
break;
|
|
case SIGSEGV:
|
|
res = "Segmentation fault";
|
|
break;
|
|
case SIGTERM:
|
|
res = "Terminated";
|
|
break;
|
|
default:
|
|
Py_RETURN_NONE;
|
|
}
|
|
#else
|
|
errno = 0;
|
|
res = strsignal(signalnum);
|
|
|
|
if (errno || res == NULL || strstr(res, "Unknown signal") != NULL)
|
|
Py_RETURN_NONE;
|
|
#endif
|
|
|
|
return Py_BuildValue("s", res);
|
|
}
|
|
|
|
#ifdef HAVE_SIGINTERRUPT
|
|
|
|
/*[clinic input]
|
|
signal.siginterrupt
|
|
|
|
signalnum: int
|
|
flag: int
|
|
/
|
|
|
|
Change system call restart behaviour.
|
|
|
|
If flag is False, system calls will be restarted when interrupted by
|
|
signal sig, else system calls will be interrupted.
|
|
[clinic start generated code]*/
|
|
|
|
static PyObject *
|
|
signal_siginterrupt_impl(PyObject *module, int signalnum, int flag)
|
|
/*[clinic end generated code: output=063816243d85dd19 input=4160acacca3e2099]*/
|
|
{
|
|
if (signalnum < 1 || signalnum >= NSIG) {
|
|
PyErr_SetString(PyExc_ValueError,
|
|
"signal number out of range");
|
|
return NULL;
|
|
}
|
|
#ifdef HAVE_SIGACTION
|
|
struct sigaction act;
|
|
(void) sigaction(signalnum, NULL, &act);
|
|
if (flag) {
|
|
act.sa_flags &= ~SA_RESTART;
|
|
}
|
|
else {
|
|
act.sa_flags |= SA_RESTART;
|
|
}
|
|
if (sigaction(signalnum, &act, NULL) < 0) {
|
|
#else
|
|
if (siginterrupt(signalnum, flag) < 0) {
|
|
#endif
|
|
PyErr_SetFromErrno(PyExc_OSError);
|
|
return NULL;
|
|
}
|
|
Py_RETURN_NONE;
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
static PyObject*
|
|
signal_set_wakeup_fd(PyObject *self, PyObject *args, PyObject *kwds)
|
|
{
|
|
struct _Py_stat_struct status;
|
|
static char *kwlist[] = {
|
|
"", "warn_on_full_buffer", NULL,
|
|
};
|
|
int warn_on_full_buffer = 1;
|
|
#ifdef MS_WINDOWS
|
|
PyObject *fdobj;
|
|
SOCKET_T sockfd, old_sockfd;
|
|
int res;
|
|
int res_size = sizeof res;
|
|
PyObject *mod;
|
|
int is_socket;
|
|
|
|
if (!PyArg_ParseTupleAndKeywords(args, kwds, "O|$p:set_wakeup_fd", kwlist,
|
|
&fdobj, &warn_on_full_buffer))
|
|
return NULL;
|
|
|
|
sockfd = PyLong_AsSocket_t(fdobj);
|
|
if (sockfd == (SOCKET_T)(-1) && PyErr_Occurred())
|
|
return NULL;
|
|
#else
|
|
int fd;
|
|
|
|
if (!PyArg_ParseTupleAndKeywords(args, kwds, "i|$p:set_wakeup_fd", kwlist,
|
|
&fd, &warn_on_full_buffer))
|
|
return NULL;
|
|
#endif
|
|
|
|
PyThreadState *tstate = _PyThreadState_GET();
|
|
if (!_Py_ThreadCanHandleSignals(tstate->interp)) {
|
|
_PyErr_SetString(tstate, PyExc_ValueError,
|
|
"set_wakeup_fd only works in main thread "
|
|
"of the main interpreter");
|
|
return NULL;
|
|
}
|
|
|
|
#ifdef MS_WINDOWS
|
|
is_socket = 0;
|
|
if (sockfd != INVALID_FD) {
|
|
/* Import the _socket module to call WSAStartup() */
|
|
mod = PyImport_ImportModuleNoBlock("_socket");
|
|
if (mod == NULL)
|
|
return NULL;
|
|
Py_DECREF(mod);
|
|
|
|
/* test the socket */
|
|
if (getsockopt(sockfd, SOL_SOCKET, SO_ERROR,
|
|
(char *)&res, &res_size) != 0) {
|
|
int fd, err;
|
|
|
|
err = WSAGetLastError();
|
|
if (err != WSAENOTSOCK) {
|
|
PyErr_SetExcFromWindowsErr(PyExc_OSError, err);
|
|
return NULL;
|
|
}
|
|
|
|
fd = (int)sockfd;
|
|
if ((SOCKET_T)fd != sockfd) {
|
|
_PyErr_SetString(tstate, PyExc_ValueError, "invalid fd");
|
|
return NULL;
|
|
}
|
|
|
|
if (_Py_fstat(fd, &status) != 0) {
|
|
return NULL;
|
|
}
|
|
|
|
/* on Windows, a file cannot be set to non-blocking mode */
|
|
}
|
|
else {
|
|
is_socket = 1;
|
|
|
|
/* Windows does not provide a function to test if a socket
|
|
is in non-blocking mode */
|
|
}
|
|
}
|
|
|
|
old_sockfd = wakeup.fd;
|
|
wakeup.fd = sockfd;
|
|
wakeup.warn_on_full_buffer = warn_on_full_buffer;
|
|
wakeup.use_send = is_socket;
|
|
|
|
if (old_sockfd != INVALID_FD)
|
|
return PyLong_FromSocket_t(old_sockfd);
|
|
else
|
|
return PyLong_FromLong(-1);
|
|
#else
|
|
if (fd != -1) {
|
|
int blocking;
|
|
|
|
if (_Py_fstat(fd, &status) != 0)
|
|
return NULL;
|
|
|
|
blocking = _Py_get_blocking(fd);
|
|
if (blocking < 0)
|
|
return NULL;
|
|
if (blocking) {
|
|
_PyErr_Format(tstate, PyExc_ValueError,
|
|
"the fd %i must be in non-blocking mode",
|
|
fd);
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
int old_fd = wakeup.fd;
|
|
wakeup.fd = fd;
|
|
wakeup.warn_on_full_buffer = warn_on_full_buffer;
|
|
|
|
return PyLong_FromLong(old_fd);
|
|
#endif
|
|
}
|
|
|
|
PyDoc_STRVAR(set_wakeup_fd_doc,
|
|
"set_wakeup_fd(fd, *, warn_on_full_buffer=True) -> fd\n\
|
|
\n\
|
|
Sets the fd to be written to (with the signal number) when a signal\n\
|
|
comes in. A library can use this to wakeup select or poll.\n\
|
|
The previous fd or -1 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)
|
|
{
|
|
if (fd < 0) {
|
|
fd = -1;
|
|
}
|
|
|
|
#ifdef MS_WINDOWS
|
|
int old_fd = Py_SAFE_DOWNCAST(wakeup.fd, SOCKET_T, int);
|
|
#else
|
|
int old_fd = wakeup.fd;
|
|
#endif
|
|
wakeup.fd = fd;
|
|
wakeup.warn_on_full_buffer = 1;
|
|
return old_fd;
|
|
}
|
|
|
|
|
|
#ifdef HAVE_SETITIMER
|
|
|
|
/*[clinic input]
|
|
signal.setitimer
|
|
|
|
which: int
|
|
seconds: object
|
|
interval: object(c_default="NULL") = 0.0
|
|
/
|
|
|
|
Sets given itimer (one of ITIMER_REAL, ITIMER_VIRTUAL or ITIMER_PROF).
|
|
|
|
The timer will fire after value seconds and after that every interval seconds.
|
|
The itimer can be cleared by setting seconds to zero.
|
|
|
|
Returns old values as a tuple: (delay, interval).
|
|
[clinic start generated code]*/
|
|
|
|
static PyObject *
|
|
signal_setitimer_impl(PyObject *module, int which, PyObject *seconds,
|
|
PyObject *interval)
|
|
/*[clinic end generated code: output=65f9dcbddc35527b input=de43daf194e6f66f]*/
|
|
{
|
|
struct itimerval new;
|
|
|
|
if (timeval_from_double(seconds, &new.it_value) < 0) {
|
|
return NULL;
|
|
}
|
|
if (timeval_from_double(interval, &new.it_interval) < 0) {
|
|
return NULL;
|
|
}
|
|
|
|
/* Let OS check "which" value */
|
|
struct itimerval old;
|
|
if (setitimer(which, &new, &old) != 0) {
|
|
PyErr_SetFromErrno(ItimerError);
|
|
return NULL;
|
|
}
|
|
|
|
return itimer_retval(&old);
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
#ifdef HAVE_GETITIMER
|
|
|
|
/*[clinic input]
|
|
signal.getitimer
|
|
|
|
which: int
|
|
/
|
|
|
|
Returns current value of given itimer.
|
|
[clinic start generated code]*/
|
|
|
|
static PyObject *
|
|
signal_getitimer_impl(PyObject *module, int which)
|
|
/*[clinic end generated code: output=9e053175d517db40 input=f7d21d38f3490627]*/
|
|
{
|
|
struct itimerval old;
|
|
|
|
if (getitimer(which, &old) != 0) {
|
|
PyErr_SetFromErrno(ItimerError);
|
|
return NULL;
|
|
}
|
|
|
|
return itimer_retval(&old);
|
|
}
|
|
|
|
#endif
|
|
|
|
#if defined(PYPTHREAD_SIGMASK) || defined(HAVE_SIGPENDING)
|
|
static PyObject*
|
|
sigset_to_set(sigset_t mask)
|
|
{
|
|
PyObject *signum, *result;
|
|
int sig;
|
|
|
|
result = PySet_New(0);
|
|
if (result == NULL)
|
|
return NULL;
|
|
|
|
for (sig = 1; sig < NSIG; sig++) {
|
|
if (sigismember(&mask, 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 (PySet_Add(result, signum) == -1) {
|
|
Py_DECREF(signum);
|
|
Py_DECREF(result);
|
|
return NULL;
|
|
}
|
|
Py_DECREF(signum);
|
|
}
|
|
return result;
|
|
}
|
|
#endif
|
|
|
|
#ifdef PYPTHREAD_SIGMASK
|
|
|
|
/*[clinic input]
|
|
signal.pthread_sigmask
|
|
|
|
how: int
|
|
mask: sigset_t
|
|
/
|
|
|
|
Fetch and/or change the signal mask of the calling thread.
|
|
[clinic start generated code]*/
|
|
|
|
static PyObject *
|
|
signal_pthread_sigmask_impl(PyObject *module, int how, sigset_t mask)
|
|
/*[clinic end generated code: output=0562c0fb192981a8 input=85bcebda442fa77f]*/
|
|
{
|
|
sigset_t previous;
|
|
int err;
|
|
|
|
err = pthread_sigmask(how, &mask, &previous);
|
|
if (err != 0) {
|
|
errno = err;
|
|
PyErr_SetFromErrno(PyExc_OSError);
|
|
return NULL;
|
|
}
|
|
|
|
/* if signals was unblocked, signal handlers have been called */
|
|
if (PyErr_CheckSignals())
|
|
return NULL;
|
|
|
|
return sigset_to_set(previous);
|
|
}
|
|
|
|
#endif /* #ifdef PYPTHREAD_SIGMASK */
|
|
|
|
|
|
#ifdef HAVE_SIGPENDING
|
|
|
|
/*[clinic input]
|
|
signal.sigpending
|
|
|
|
Examine pending signals.
|
|
|
|
Returns a set of signal numbers that are pending for delivery to
|
|
the calling thread.
|
|
[clinic start generated code]*/
|
|
|
|
static PyObject *
|
|
signal_sigpending_impl(PyObject *module)
|
|
/*[clinic end generated code: output=53375ffe89325022 input=e0036c016f874e29]*/
|
|
{
|
|
int err;
|
|
sigset_t mask;
|
|
err = sigpending(&mask);
|
|
if (err)
|
|
return PyErr_SetFromErrno(PyExc_OSError);
|
|
return sigset_to_set(mask);
|
|
}
|
|
|
|
#endif /* #ifdef HAVE_SIGPENDING */
|
|
|
|
|
|
#ifdef HAVE_SIGWAIT
|
|
|
|
/*[clinic input]
|
|
signal.sigwait
|
|
|
|
sigset: sigset_t
|
|
/
|
|
|
|
Wait for a signal.
|
|
|
|
Suspend execution of the calling thread until the delivery of one of the
|
|
signals specified in the signal set sigset. The function accepts the signal
|
|
and returns the signal number.
|
|
[clinic start generated code]*/
|
|
|
|
static PyObject *
|
|
signal_sigwait_impl(PyObject *module, sigset_t sigset)
|
|
/*[clinic end generated code: output=f43770699d682f96 input=a6fbd47b1086d119]*/
|
|
{
|
|
int err, signum;
|
|
|
|
Py_BEGIN_ALLOW_THREADS
|
|
err = sigwait(&sigset, &signum);
|
|
Py_END_ALLOW_THREADS
|
|
if (err) {
|
|
errno = err;
|
|
return PyErr_SetFromErrno(PyExc_OSError);
|
|
}
|
|
|
|
return PyLong_FromLong(signum);
|
|
}
|
|
|
|
#endif /* #ifdef HAVE_SIGWAIT */
|
|
|
|
|
|
#if defined(HAVE_SIGFILLSET) || defined(MS_WINDOWS)
|
|
|
|
/*[clinic input]
|
|
signal.valid_signals
|
|
|
|
Return a set of valid signal numbers on this platform.
|
|
|
|
The signal numbers returned by this function can be safely passed to
|
|
functions like `pthread_sigmask`.
|
|
[clinic start generated code]*/
|
|
|
|
static PyObject *
|
|
signal_valid_signals_impl(PyObject *module)
|
|
/*[clinic end generated code: output=1609cffbcfcf1314 input=86a3717ff25288f2]*/
|
|
{
|
|
#ifdef MS_WINDOWS
|
|
#ifdef SIGBREAK
|
|
PyObject *tup = Py_BuildValue("(iiiiiii)", SIGABRT, SIGBREAK, SIGFPE,
|
|
SIGILL, SIGINT, SIGSEGV, SIGTERM);
|
|
#else
|
|
PyObject *tup = Py_BuildValue("(iiiiii)", SIGABRT, SIGFPE, SIGILL,
|
|
SIGINT, SIGSEGV, SIGTERM);
|
|
#endif
|
|
if (tup == NULL) {
|
|
return NULL;
|
|
}
|
|
PyObject *set = PySet_New(tup);
|
|
Py_DECREF(tup);
|
|
return set;
|
|
#else
|
|
sigset_t mask;
|
|
if (sigemptyset(&mask) || sigfillset(&mask)) {
|
|
return PyErr_SetFromErrno(PyExc_OSError);
|
|
}
|
|
return sigset_to_set(mask);
|
|
#endif
|
|
}
|
|
|
|
#endif /* #if defined(HAVE_SIGFILLSET) || defined(MS_WINDOWS) */
|
|
|
|
|
|
#if defined(HAVE_SIGWAITINFO) || defined(HAVE_SIGTIMEDWAIT)
|
|
static PyStructSequence_Field struct_siginfo_fields[] = {
|
|
{"si_signo", "signal number"},
|
|
{"si_code", "signal code"},
|
|
{"si_errno", "errno associated with this signal"},
|
|
{"si_pid", "sending process ID"},
|
|
{"si_uid", "real user ID of sending process"},
|
|
{"si_status", "exit value or signal"},
|
|
{"si_band", "band event for SIGPOLL"},
|
|
{0}
|
|
};
|
|
|
|
PyDoc_STRVAR(struct_siginfo__doc__,
|
|
"struct_siginfo: Result from sigwaitinfo or sigtimedwait.\n\n\
|
|
This object may be accessed either as a tuple of\n\
|
|
(si_signo, si_code, si_errno, si_pid, si_uid, si_status, si_band),\n\
|
|
or via the attributes si_signo, si_code, and so on.");
|
|
|
|
static PyStructSequence_Desc struct_siginfo_desc = {
|
|
"signal.struct_siginfo", /* name */
|
|
struct_siginfo__doc__, /* doc */
|
|
struct_siginfo_fields, /* fields */
|
|
7 /* n_in_sequence */
|
|
};
|
|
|
|
static PyTypeObject SiginfoType;
|
|
|
|
static PyObject *
|
|
fill_siginfo(siginfo_t *si)
|
|
{
|
|
PyObject *result = PyStructSequence_New(&SiginfoType);
|
|
if (!result)
|
|
return NULL;
|
|
|
|
PyStructSequence_SET_ITEM(result, 0, PyLong_FromLong((long)(si->si_signo)));
|
|
PyStructSequence_SET_ITEM(result, 1, PyLong_FromLong((long)(si->si_code)));
|
|
#ifdef __VXWORKS__
|
|
PyStructSequence_SET_ITEM(result, 2, PyLong_FromLong(0L));
|
|
PyStructSequence_SET_ITEM(result, 3, PyLong_FromLong(0L));
|
|
PyStructSequence_SET_ITEM(result, 4, PyLong_FromLong(0L));
|
|
PyStructSequence_SET_ITEM(result, 5, PyLong_FromLong(0L));
|
|
#else
|
|
PyStructSequence_SET_ITEM(result, 2, PyLong_FromLong((long)(si->si_errno)));
|
|
PyStructSequence_SET_ITEM(result, 3, PyLong_FromPid(si->si_pid));
|
|
PyStructSequence_SET_ITEM(result, 4, _PyLong_FromUid(si->si_uid));
|
|
PyStructSequence_SET_ITEM(result, 5,
|
|
PyLong_FromLong((long)(si->si_status)));
|
|
#endif
|
|
#ifdef HAVE_SIGINFO_T_SI_BAND
|
|
PyStructSequence_SET_ITEM(result, 6, PyLong_FromLong(si->si_band));
|
|
#else
|
|
PyStructSequence_SET_ITEM(result, 6, PyLong_FromLong(0L));
|
|
#endif
|
|
if (PyErr_Occurred()) {
|
|
Py_DECREF(result);
|
|
return NULL;
|
|
}
|
|
|
|
return result;
|
|
}
|
|
#endif
|
|
|
|
#ifdef HAVE_SIGWAITINFO
|
|
|
|
/*[clinic input]
|
|
signal.sigwaitinfo
|
|
|
|
sigset: sigset_t
|
|
/
|
|
|
|
Wait synchronously until one of the signals in *sigset* is delivered.
|
|
|
|
Returns a struct_siginfo containing information about the signal.
|
|
[clinic start generated code]*/
|
|
|
|
static PyObject *
|
|
signal_sigwaitinfo_impl(PyObject *module, sigset_t sigset)
|
|
/*[clinic end generated code: output=1eb2f1fa236fdbca input=3d1a7e1f27fc664c]*/
|
|
{
|
|
siginfo_t si;
|
|
int err;
|
|
int async_err = 0;
|
|
|
|
do {
|
|
Py_BEGIN_ALLOW_THREADS
|
|
err = sigwaitinfo(&sigset, &si);
|
|
Py_END_ALLOW_THREADS
|
|
} while (err == -1
|
|
&& errno == EINTR && !(async_err = PyErr_CheckSignals()));
|
|
if (err == -1)
|
|
return (!async_err) ? PyErr_SetFromErrno(PyExc_OSError) : NULL;
|
|
|
|
return fill_siginfo(&si);
|
|
}
|
|
|
|
#endif /* #ifdef HAVE_SIGWAITINFO */
|
|
|
|
#ifdef HAVE_SIGTIMEDWAIT
|
|
|
|
/*[clinic input]
|
|
signal.sigtimedwait
|
|
|
|
sigset: sigset_t
|
|
timeout as timeout_obj: object
|
|
/
|
|
|
|
Like sigwaitinfo(), but with a timeout.
|
|
|
|
The timeout is specified in seconds, with floating point numbers allowed.
|
|
[clinic start generated code]*/
|
|
|
|
static PyObject *
|
|
signal_sigtimedwait_impl(PyObject *module, sigset_t sigset,
|
|
PyObject *timeout_obj)
|
|
/*[clinic end generated code: output=59c8971e8ae18a64 input=87fd39237cf0b7ba]*/
|
|
{
|
|
struct timespec ts;
|
|
siginfo_t si;
|
|
int res;
|
|
_PyTime_t timeout, deadline, monotonic;
|
|
|
|
if (_PyTime_FromSecondsObject(&timeout,
|
|
timeout_obj, _PyTime_ROUND_CEILING) < 0)
|
|
return NULL;
|
|
|
|
if (timeout < 0) {
|
|
PyErr_SetString(PyExc_ValueError, "timeout must be non-negative");
|
|
return NULL;
|
|
}
|
|
|
|
deadline = _PyTime_GetMonotonicClock() + timeout;
|
|
|
|
do {
|
|
if (_PyTime_AsTimespec(timeout, &ts) < 0)
|
|
return NULL;
|
|
|
|
Py_BEGIN_ALLOW_THREADS
|
|
res = sigtimedwait(&sigset, &si, &ts);
|
|
Py_END_ALLOW_THREADS
|
|
|
|
if (res != -1)
|
|
break;
|
|
|
|
if (errno != EINTR) {
|
|
if (errno == EAGAIN)
|
|
Py_RETURN_NONE;
|
|
else
|
|
return PyErr_SetFromErrno(PyExc_OSError);
|
|
}
|
|
|
|
/* sigtimedwait() was interrupted by a signal (EINTR) */
|
|
if (PyErr_CheckSignals())
|
|
return NULL;
|
|
|
|
monotonic = _PyTime_GetMonotonicClock();
|
|
timeout = deadline - monotonic;
|
|
if (timeout < 0)
|
|
break;
|
|
} while (1);
|
|
|
|
return fill_siginfo(&si);
|
|
}
|
|
|
|
#endif /* #ifdef HAVE_SIGTIMEDWAIT */
|
|
|
|
|
|
#if defined(HAVE_PTHREAD_KILL)
|
|
|
|
/*[clinic input]
|
|
signal.pthread_kill
|
|
|
|
thread_id: unsigned_long(bitwise=True)
|
|
signalnum: int
|
|
/
|
|
|
|
Send a signal to a thread.
|
|
[clinic start generated code]*/
|
|
|
|
static PyObject *
|
|
signal_pthread_kill_impl(PyObject *module, unsigned long thread_id,
|
|
int signalnum)
|
|
/*[clinic end generated code: output=7629919b791bc27f input=1d901f2c7bb544ff]*/
|
|
{
|
|
int err;
|
|
|
|
if (PySys_Audit("signal.pthread_kill", "ki", thread_id, signalnum) < 0) {
|
|
return NULL;
|
|
}
|
|
|
|
err = pthread_kill((pthread_t)thread_id, signalnum);
|
|
if (err != 0) {
|
|
errno = err;
|
|
PyErr_SetFromErrno(PyExc_OSError);
|
|
return NULL;
|
|
}
|
|
|
|
/* the signal may have been send to the current thread */
|
|
if (PyErr_CheckSignals())
|
|
return NULL;
|
|
|
|
Py_RETURN_NONE;
|
|
}
|
|
|
|
#endif /* #if defined(HAVE_PTHREAD_KILL) */
|
|
|
|
|
|
#if defined(__linux__) && defined(__NR_pidfd_send_signal)
|
|
/*[clinic input]
|
|
signal.pidfd_send_signal
|
|
|
|
pidfd: int
|
|
signalnum: int
|
|
siginfo: object = None
|
|
flags: int = 0
|
|
/
|
|
|
|
Send a signal to a process referred to by a pid file descriptor.
|
|
[clinic start generated code]*/
|
|
|
|
static PyObject *
|
|
signal_pidfd_send_signal_impl(PyObject *module, int pidfd, int signalnum,
|
|
PyObject *siginfo, int flags)
|
|
/*[clinic end generated code: output=2d59f04a75d9cbdf input=2a6543a1f4ac2000]*/
|
|
|
|
{
|
|
if (siginfo != Py_None) {
|
|
PyErr_SetString(PyExc_TypeError, "siginfo must be None");
|
|
return NULL;
|
|
}
|
|
if (syscall(__NR_pidfd_send_signal, pidfd, signalnum, NULL, flags) < 0) {
|
|
PyErr_SetFromErrno(PyExc_OSError);
|
|
return NULL;
|
|
}
|
|
Py_RETURN_NONE;
|
|
}
|
|
#endif
|
|
|
|
|
|
|
|
/* List of functions defined in the module -- some of the methoddefs are
|
|
defined to nothing if the corresponding C function is not available. */
|
|
static PyMethodDef signal_methods[] = {
|
|
SIGNAL_DEFAULT_INT_HANDLER_METHODDEF
|
|
SIGNAL_ALARM_METHODDEF
|
|
SIGNAL_SETITIMER_METHODDEF
|
|
SIGNAL_GETITIMER_METHODDEF
|
|
SIGNAL_SIGNAL_METHODDEF
|
|
SIGNAL_RAISE_SIGNAL_METHODDEF
|
|
SIGNAL_STRSIGNAL_METHODDEF
|
|
SIGNAL_GETSIGNAL_METHODDEF
|
|
{"set_wakeup_fd", (PyCFunction)(void(*)(void))signal_set_wakeup_fd, METH_VARARGS | METH_KEYWORDS, set_wakeup_fd_doc},
|
|
SIGNAL_SIGINTERRUPT_METHODDEF
|
|
SIGNAL_PAUSE_METHODDEF
|
|
SIGNAL_PIDFD_SEND_SIGNAL_METHODDEF
|
|
SIGNAL_PTHREAD_KILL_METHODDEF
|
|
SIGNAL_PTHREAD_SIGMASK_METHODDEF
|
|
SIGNAL_SIGPENDING_METHODDEF
|
|
SIGNAL_SIGWAIT_METHODDEF
|
|
SIGNAL_SIGWAITINFO_METHODDEF
|
|
SIGNAL_SIGTIMEDWAIT_METHODDEF
|
|
#if defined(HAVE_SIGFILLSET) || defined(MS_WINDOWS)
|
|
SIGNAL_VALID_SIGNALS_METHODDEF
|
|
#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 int
|
|
signal_add_constants(PyObject *module)
|
|
{
|
|
#define ADD_INT_MACRO(macro) \
|
|
if (PyModule_AddIntConstant(module, #macro, macro) < 0) { \
|
|
return -1; \
|
|
}
|
|
|
|
ADD_INT_MACRO(NSIG);
|
|
|
|
// SIG_xxx pthread_sigmask() constants
|
|
#ifdef SIG_BLOCK
|
|
ADD_INT_MACRO(SIG_BLOCK);
|
|
#endif
|
|
#ifdef SIG_UNBLOCK
|
|
ADD_INT_MACRO(SIG_UNBLOCK);
|
|
#endif
|
|
#ifdef SIG_SETMASK
|
|
ADD_INT_MACRO(SIG_SETMASK);
|
|
#endif
|
|
|
|
// SIGxxx signal number constants
|
|
#ifdef SIGHUP
|
|
ADD_INT_MACRO(SIGHUP);
|
|
#endif
|
|
#ifdef SIGINT
|
|
ADD_INT_MACRO(SIGINT);
|
|
#endif
|
|
#ifdef SIGBREAK
|
|
ADD_INT_MACRO(SIGBREAK);
|
|
#endif
|
|
#ifdef SIGQUIT
|
|
ADD_INT_MACRO(SIGQUIT);
|
|
#endif
|
|
#ifdef SIGILL
|
|
ADD_INT_MACRO(SIGILL);
|
|
#endif
|
|
#ifdef SIGTRAP
|
|
ADD_INT_MACRO(SIGTRAP);
|
|
#endif
|
|
#ifdef SIGIOT
|
|
ADD_INT_MACRO(SIGIOT);
|
|
#endif
|
|
#ifdef SIGABRT
|
|
ADD_INT_MACRO(SIGABRT);
|
|
#endif
|
|
#ifdef SIGEMT
|
|
ADD_INT_MACRO(SIGEMT);
|
|
#endif
|
|
#ifdef SIGFPE
|
|
ADD_INT_MACRO(SIGFPE);
|
|
#endif
|
|
#ifdef SIGKILL
|
|
ADD_INT_MACRO(SIGKILL);
|
|
#endif
|
|
#ifdef SIGBUS
|
|
ADD_INT_MACRO(SIGBUS);
|
|
#endif
|
|
#ifdef SIGSEGV
|
|
ADD_INT_MACRO(SIGSEGV);
|
|
#endif
|
|
#ifdef SIGSYS
|
|
ADD_INT_MACRO(SIGSYS);
|
|
#endif
|
|
#ifdef SIGPIPE
|
|
ADD_INT_MACRO(SIGPIPE);
|
|
#endif
|
|
#ifdef SIGALRM
|
|
ADD_INT_MACRO(SIGALRM);
|
|
#endif
|
|
#ifdef SIGTERM
|
|
ADD_INT_MACRO(SIGTERM);
|
|
#endif
|
|
#ifdef SIGUSR1
|
|
ADD_INT_MACRO(SIGUSR1);
|
|
#endif
|
|
#ifdef SIGUSR2
|
|
ADD_INT_MACRO(SIGUSR2);
|
|
#endif
|
|
#ifdef SIGCLD
|
|
ADD_INT_MACRO(SIGCLD);
|
|
#endif
|
|
#ifdef SIGCHLD
|
|
ADD_INT_MACRO(SIGCHLD);
|
|
#endif
|
|
#ifdef SIGPWR
|
|
ADD_INT_MACRO(SIGPWR);
|
|
#endif
|
|
#ifdef SIGIO
|
|
ADD_INT_MACRO(SIGIO);
|
|
#endif
|
|
#ifdef SIGURG
|
|
ADD_INT_MACRO(SIGURG);
|
|
#endif
|
|
#ifdef SIGWINCH
|
|
ADD_INT_MACRO(SIGWINCH);
|
|
#endif
|
|
#ifdef SIGPOLL
|
|
ADD_INT_MACRO(SIGPOLL);
|
|
#endif
|
|
#ifdef SIGSTOP
|
|
ADD_INT_MACRO(SIGSTOP);
|
|
#endif
|
|
#ifdef SIGTSTP
|
|
ADD_INT_MACRO(SIGTSTP);
|
|
#endif
|
|
#ifdef SIGCONT
|
|
ADD_INT_MACRO(SIGCONT);
|
|
#endif
|
|
#ifdef SIGTTIN
|
|
ADD_INT_MACRO(SIGTTIN);
|
|
#endif
|
|
#ifdef SIGTTOU
|
|
ADD_INT_MACRO(SIGTTOU);
|
|
#endif
|
|
#ifdef SIGVTALRM
|
|
ADD_INT_MACRO(SIGVTALRM);
|
|
#endif
|
|
#ifdef SIGPROF
|
|
ADD_INT_MACRO(SIGPROF);
|
|
#endif
|
|
#ifdef SIGXCPU
|
|
ADD_INT_MACRO(SIGXCPU);
|
|
#endif
|
|
#ifdef SIGXFSZ
|
|
ADD_INT_MACRO(SIGXFSZ);
|
|
#endif
|
|
#ifdef SIGRTMIN
|
|
ADD_INT_MACRO(SIGRTMIN);
|
|
#endif
|
|
#ifdef SIGRTMAX
|
|
ADD_INT_MACRO(SIGRTMAX);
|
|
#endif
|
|
#ifdef SIGINFO
|
|
ADD_INT_MACRO(SIGINFO);
|
|
#endif
|
|
|
|
// ITIMER_xxx constants
|
|
#ifdef ITIMER_REAL
|
|
ADD_INT_MACRO(ITIMER_REAL);
|
|
#endif
|
|
#ifdef ITIMER_VIRTUAL
|
|
ADD_INT_MACRO(ITIMER_VIRTUAL);
|
|
#endif
|
|
#ifdef ITIMER_PROF
|
|
ADD_INT_MACRO(ITIMER_PROF);
|
|
#endif
|
|
|
|
// CTRL_xxx Windows signals
|
|
#ifdef CTRL_C_EVENT
|
|
ADD_INT_MACRO(CTRL_C_EVENT);
|
|
#endif
|
|
#ifdef CTRL_BREAK_EVENT
|
|
ADD_INT_MACRO(CTRL_BREAK_EVENT);
|
|
#endif
|
|
|
|
return 0;
|
|
|
|
#undef ADD_INT_MACRO
|
|
}
|
|
|
|
|
|
static int
|
|
signal_module_exec(PyObject *m)
|
|
{
|
|
assert(!PyErr_Occurred());
|
|
|
|
if (signal_add_constants(m) < 0) {
|
|
return -1;
|
|
}
|
|
|
|
/* Add some symbolic constants to the module */
|
|
PyObject *d = PyModule_GetDict(m);
|
|
if (PyDict_SetItemString(d, "SIG_DFL", DefaultHandler) < 0) {
|
|
return -1;
|
|
}
|
|
if (PyDict_SetItemString(d, "SIG_IGN", IgnoreHandler) < 0) {
|
|
return -1;
|
|
}
|
|
#if defined(HAVE_GETITIMER) || defined(HAVE_SETITIMER)
|
|
if (PyDict_SetItemString(d, "ItimerError", ItimerError) < 0) {
|
|
return -1;
|
|
}
|
|
#endif
|
|
#if defined(HAVE_SIGWAITINFO) || defined(HAVE_SIGTIMEDWAIT)
|
|
if (PyModule_AddType(m, &SiginfoType) < 0) {
|
|
return -1;
|
|
}
|
|
#endif
|
|
|
|
// Get signal handlers
|
|
for (int signum = 1; signum < NSIG; signum++) {
|
|
void (*c_handler)(int) = PyOS_getsig(signum);
|
|
PyObject *func;
|
|
if (c_handler == SIG_DFL) {
|
|
func = DefaultHandler;
|
|
}
|
|
else if (c_handler == SIG_IGN) {
|
|
func = IgnoreHandler;
|
|
}
|
|
else {
|
|
func = Py_None; // None of our business
|
|
}
|
|
// If signal_module_exec() is called more than one, we must
|
|
// clear the strong reference to the previous function.
|
|
PyObject* old_func = get_handler(signum);
|
|
SetHandler(signum, Py_NewRef(func));
|
|
Py_XDECREF(old_func);
|
|
}
|
|
|
|
// Instal Python SIGINT handler which raises KeyboardInterrupt
|
|
PyObject* sigint_func = get_handler(SIGINT);
|
|
if (sigint_func == DefaultHandler) {
|
|
PyObject *int_handler = PyMapping_GetItemString(d, "default_int_handler");
|
|
if (!int_handler) {
|
|
return -1;
|
|
}
|
|
|
|
SetHandler(SIGINT, int_handler);
|
|
Py_DECREF(sigint_func);
|
|
PyOS_setsig(SIGINT, signal_handler);
|
|
}
|
|
|
|
assert(!PyErr_Occurred());
|
|
return 0;
|
|
}
|
|
|
|
|
|
static PyModuleDef_Slot signal_slots[] = {
|
|
{Py_mod_exec, signal_module_exec},
|
|
{0, NULL}
|
|
};
|
|
|
|
static struct PyModuleDef signal_module = {
|
|
PyModuleDef_HEAD_INIT,
|
|
"_signal",
|
|
.m_doc = module_doc,
|
|
.m_size = 0,
|
|
.m_methods = signal_methods,
|
|
.m_slots = signal_slots,
|
|
};
|
|
|
|
|
|
PyMODINIT_FUNC
|
|
PyInit__signal(void)
|
|
{
|
|
return PyModuleDef_Init(&signal_module);
|
|
}
|
|
|
|
|
|
void
|
|
_PySignal_Fini(void)
|
|
{
|
|
// Restore default signals and clear handlers
|
|
for (int signum = 1; signum < NSIG; signum++) {
|
|
PyObject *func = get_handler(signum);
|
|
_Py_atomic_store_relaxed(&Handlers[signum].tripped, 0);
|
|
SetHandler(signum, NULL);
|
|
if (func != NULL
|
|
&& func != Py_None
|
|
&& func != DefaultHandler
|
|
&& func != IgnoreHandler)
|
|
{
|
|
PyOS_setsig(signum, SIG_DFL);
|
|
}
|
|
Py_XDECREF(func);
|
|
}
|
|
|
|
#ifdef MS_WINDOWS
|
|
if (sigint_event != NULL) {
|
|
CloseHandle(sigint_event);
|
|
sigint_event = NULL;
|
|
}
|
|
#endif
|
|
|
|
Py_CLEAR(DefaultHandler);
|
|
Py_CLEAR(IgnoreHandler);
|
|
#if defined(HAVE_GETITIMER) || defined(HAVE_SETITIMER)
|
|
Py_CLEAR(ItimerError);
|
|
#endif
|
|
}
|
|
|
|
|
|
/* Declared in pyerrors.h */
|
|
int
|
|
PyErr_CheckSignals(void)
|
|
{
|
|
PyThreadState *tstate = _PyThreadState_GET();
|
|
if (!_Py_ThreadCanHandleSignals(tstate->interp)) {
|
|
return 0;
|
|
}
|
|
|
|
return _PyErr_CheckSignalsTstate(tstate);
|
|
}
|
|
|
|
|
|
/* Declared in cpython/pyerrors.h */
|
|
int
|
|
_PyErr_CheckSignalsTstate(PyThreadState *tstate)
|
|
{
|
|
if (!_Py_atomic_load(&is_tripped)) {
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
_Py_atomic_store(&is_tripped, 0);
|
|
|
|
PyObject *frame = (PyObject *)tstate->frame;
|
|
if (!frame) {
|
|
frame = Py_None;
|
|
}
|
|
|
|
for (int i = 1; i < NSIG; i++) {
|
|
if (!_Py_atomic_load_relaxed(&Handlers[i].tripped)) {
|
|
continue;
|
|
}
|
|
_Py_atomic_store_relaxed(&Handlers[i].tripped, 0);
|
|
|
|
/* Signal handlers can be modified while a signal is received,
|
|
* and therefore the fact that trip_signal() or PyErr_SetInterrupt()
|
|
* was called doesn't guarantee that there is still a Python
|
|
* signal handler for it by the time PyErr_CheckSignals() is called
|
|
* (see bpo-43406).
|
|
*/
|
|
PyObject *func = get_handler(i);
|
|
if (func == NULL || func == Py_None || func == IgnoreHandler ||
|
|
func == DefaultHandler) {
|
|
/* No Python signal handler due to aforementioned race condition.
|
|
* We can't call raise() as it would break the assumption
|
|
* that PyErr_SetInterrupt() only *simulates* an incoming
|
|
* signal (i.e. it will never kill the process).
|
|
* We also don't want to interrupt user code with a cryptic
|
|
* asynchronous exception, so instead just write out an
|
|
* unraisable error.
|
|
*/
|
|
PyErr_Format(PyExc_OSError,
|
|
"Signal %i ignored due to race condition",
|
|
i);
|
|
PyErr_WriteUnraisable(Py_None);
|
|
continue;
|
|
}
|
|
|
|
PyObject *arglist = Py_BuildValue("(iO)", i, frame);
|
|
PyObject *result;
|
|
if (arglist) {
|
|
result = _PyObject_Call(tstate, func, arglist, NULL);
|
|
Py_DECREF(arglist);
|
|
}
|
|
else {
|
|
result = NULL;
|
|
}
|
|
if (!result) {
|
|
/* On error, re-schedule a call to _PyErr_CheckSignalsTstate() */
|
|
_Py_atomic_store(&is_tripped, 1);
|
|
return -1;
|
|
}
|
|
|
|
Py_DECREF(result);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
|
|
int
|
|
_PyErr_CheckSignals(void)
|
|
{
|
|
PyThreadState *tstate = _PyThreadState_GET();
|
|
return _PyErr_CheckSignalsTstate(tstate);
|
|
}
|
|
|
|
|
|
/* Simulate the effect of a signal arriving. The next time PyErr_CheckSignals
|
|
is called, the corresponding Python signal handler will be raised.
|
|
|
|
Missing signal handler for the given signal number is silently ignored. */
|
|
int
|
|
PyErr_SetInterruptEx(int signum)
|
|
{
|
|
if (signum < 1 || signum >= NSIG) {
|
|
return -1;
|
|
}
|
|
PyObject* func = get_handler(signum);
|
|
if (func != IgnoreHandler && func != DefaultHandler) {
|
|
trip_signal(signum);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
void
|
|
PyErr_SetInterrupt(void)
|
|
{
|
|
(void) PyErr_SetInterruptEx(SIGINT);
|
|
}
|
|
|
|
static int
|
|
signal_install_handlers(void)
|
|
{
|
|
#ifdef SIGPIPE
|
|
PyOS_setsig(SIGPIPE, SIG_IGN);
|
|
#endif
|
|
#ifdef SIGXFZ
|
|
PyOS_setsig(SIGXFZ, SIG_IGN);
|
|
#endif
|
|
#ifdef SIGXFSZ
|
|
PyOS_setsig(SIGXFSZ, SIG_IGN);
|
|
#endif
|
|
|
|
// Import _signal to install the Python SIGINT handler
|
|
PyObject *module = PyImport_ImportModule("_signal");
|
|
if (!module) {
|
|
return -1;
|
|
}
|
|
Py_DECREF(module);
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/* Restore signals that the interpreter has called SIG_IGN on to SIG_DFL.
|
|
*
|
|
* All of the code in this function must only use async-signal-safe functions,
|
|
* listed at `man 7 signal` or
|
|
* http://www.opengroup.org/onlinepubs/009695399/functions/xsh_chap02_04.html.
|
|
*
|
|
* If this function is updated, update also _posix_spawn() of subprocess.py.
|
|
*/
|
|
void
|
|
_Py_RestoreSignals(void)
|
|
{
|
|
#ifdef SIGPIPE
|
|
PyOS_setsig(SIGPIPE, SIG_DFL);
|
|
#endif
|
|
#ifdef SIGXFZ
|
|
PyOS_setsig(SIGXFZ, SIG_DFL);
|
|
#endif
|
|
#ifdef SIGXFSZ
|
|
PyOS_setsig(SIGXFSZ, SIG_DFL);
|
|
#endif
|
|
}
|
|
|
|
|
|
int
|
|
_PySignal_Init(int install_signal_handlers)
|
|
{
|
|
DefaultHandler = PyLong_FromVoidPtr((void *)SIG_DFL);
|
|
if (!DefaultHandler) {
|
|
return -1;
|
|
}
|
|
|
|
IgnoreHandler = PyLong_FromVoidPtr((void *)SIG_IGN);
|
|
if (!IgnoreHandler) {
|
|
return -1;
|
|
}
|
|
|
|
#if defined(HAVE_GETITIMER) || defined(HAVE_SETITIMER)
|
|
ItimerError = PyErr_NewException("signal.ItimerError",
|
|
PyExc_OSError, NULL);
|
|
if (!ItimerError) {
|
|
return -1;
|
|
}
|
|
#endif
|
|
|
|
#ifdef MS_WINDOWS
|
|
/* Create manual-reset event, initially unset */
|
|
sigint_event = CreateEvent(NULL, TRUE, FALSE, FALSE);
|
|
if (sigint_event == NULL) {
|
|
PyErr_SetFromWindowsErr(0);
|
|
return -1;
|
|
}
|
|
#endif
|
|
|
|
#if defined(HAVE_SIGWAITINFO) || defined(HAVE_SIGTIMEDWAIT)
|
|
if (SiginfoType.tp_name == NULL) {
|
|
if (PyStructSequence_InitType2(&SiginfoType, &struct_siginfo_desc) < 0) {
|
|
return -1;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
for (int signum = 1; signum < NSIG; signum++) {
|
|
_Py_atomic_store_relaxed(&Handlers[signum].tripped, 0);
|
|
}
|
|
|
|
if (install_signal_handlers) {
|
|
if (signal_install_handlers() < 0) {
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
// The caller doesn't have to hold the GIL
|
|
int
|
|
_PyOS_InterruptOccurred(PyThreadState *tstate)
|
|
{
|
|
_Py_EnsureTstateNotNULL(tstate);
|
|
if (!_Py_ThreadCanHandleSignals(tstate->interp)) {
|
|
return 0;
|
|
}
|
|
|
|
if (!_Py_atomic_load_relaxed(&Handlers[SIGINT].tripped)) {
|
|
return 0;
|
|
}
|
|
|
|
_Py_atomic_store_relaxed(&Handlers[SIGINT].tripped, 0);
|
|
return 1;
|
|
}
|
|
|
|
|
|
// The caller must to hold the GIL
|
|
int
|
|
PyOS_InterruptOccurred(void)
|
|
{
|
|
PyThreadState *tstate = _PyThreadState_GET();
|
|
return _PyOS_InterruptOccurred(tstate);
|
|
}
|
|
|
|
|
|
#ifdef HAVE_FORK
|
|
static void
|
|
_clear_pending_signals(void)
|
|
{
|
|
if (!_Py_atomic_load(&is_tripped)) {
|
|
return;
|
|
}
|
|
|
|
_Py_atomic_store(&is_tripped, 0);
|
|
for (int i = 1; i < NSIG; ++i) {
|
|
_Py_atomic_store_relaxed(&Handlers[i].tripped, 0);
|
|
}
|
|
}
|
|
|
|
void
|
|
_PySignal_AfterFork(void)
|
|
{
|
|
/* Clear the signal flags after forking so that they aren't handled
|
|
* in both processes if they came in just before the fork() but before
|
|
* the interpreter had an opportunity to call the handlers. issue9535. */
|
|
_clear_pending_signals();
|
|
}
|
|
#endif /* HAVE_FORK */
|
|
|
|
|
|
int
|
|
_PyOS_IsMainThread(void)
|
|
{
|
|
PyInterpreterState *interp = _PyInterpreterState_GET();
|
|
return _Py_ThreadCanHandleSignals(interp);
|
|
}
|
|
|
|
#ifdef MS_WINDOWS
|
|
void *_PyOS_SigintEvent(void)
|
|
{
|
|
/* Returns a manual-reset event which gets tripped whenever
|
|
SIGINT is received.
|
|
|
|
Python.h does not include windows.h so we do cannot use HANDLE
|
|
as the return type of this function. We use void* instead. */
|
|
return sigint_event;
|
|
}
|
|
#endif
|