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2088 lines (1757 loc) · 54.5 KB
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/* Signal module -- many thanks to Lance Ellinghaus */
/* XXX Signals should be recorded per thread, now we have thread state. */
#include "Python.h"
#include "pycore_call.h" // _PyObject_Call()
#include "pycore_ceval.h" // _PyEval_SignalReceived()
#include "pycore_emscripten_signal.h" // _Py_CHECK_EMSCRIPTEN_SIGNALS
#include "pycore_fileutils.h" // _Py_BEGIN_SUPPRESS_IPH
#include "pycore_interpframe.h" // _PyThreadState_GetFrame()
#include "pycore_moduleobject.h" // _PyModule_GetState()
#include "pycore_pyerrors.h" // _PyErr_SetString()
#include "pycore_pystate.h" // _PyThreadState_GET()
#include "pycore_signal.h" // _Py_RestoreSignals()
#include "pycore_time.h" // _PyTime_FromSecondsObject()
#include "pycore_tuple.h" // _PyTuple_FromPairSteal
#ifndef MS_WINDOWS
# include "posixmodule.h" // _PyLong_FromUid()
#endif
#ifdef MS_WINDOWS
# include "socketmodule.h" // SOCKET_T
#endif
#ifdef HAVE_UNISTD_H
# include <unistd.h> // alarm()
#endif
#ifdef MS_WINDOWS
# ifdef HAVE_PROCESS_H
# include <process.h>
# endif
#endif
#ifdef HAVE_SIGNAL_H
# include <signal.h> // sigaction()
#endif
#ifdef HAVE_SYS_SYSCALL_H
# include <sys/syscall.h> // __NR_pidfd_send_signal
#endif
#ifdef HAVE_SYS_STAT_H
# include <sys/stat.h>
#endif
#ifdef HAVE_SYS_TIME_H
# include <sys/time.h> // setitimer()
#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
#ifdef HAVE_SYS_PIDFD_H
# include <sys/pidfd.h> // pidfd_send_signal()
#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]*/
#ifdef HAVE_SETSIG_T
/*[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]*/
#endif
/*
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.
*/
#define Handlers _PyRuntime.signals.handlers
#define wakeup _PyRuntime.signals.wakeup
#define is_tripped _PyRuntime.signals.is_tripped
// State shared by all Python interpreters
typedef struct _signals_runtime_state signal_state_t;
#define signal_global_state _PyRuntime.signals
#if defined(HAVE_GETITIMER) || defined(HAVE_SETITIMER)
# define PYHAVE_ITIMER_ERROR
#endif
typedef struct {
PyObject *default_handler; // borrowed ref (signal_global_state)
PyObject *ignore_handler; // borrowed ref (signal_global_state)
#ifdef PYHAVE_ITIMER_ERROR
PyObject *itimer_error;
#endif
PyTypeObject *siginfo_type;
} _signal_module_state;
Py_LOCAL_INLINE(PyObject *)
get_handler(int i)
{
return (PyObject *)_Py_atomic_load_ptr(&Handlers[i].func);
}
Py_LOCAL_INLINE(void)
set_handler(int i, PyObject* func)
{
/* Store func with atomic operation to ensure
that PyErr_SetInterrupt is async-signal-safe. */
_Py_atomic_store_ptr(&Handlers[i].func, func);
}
static inline _signal_module_state*
get_signal_state(PyObject *module)
{
void *state = _PyModule_GetState(module);
assert(state != NULL);
return (_signal_module_state *)state;
}
static inline int
compare_handler(PyObject *func, PyObject *dfl_ign_handler)
{
// See https://github.com/python/cpython/pull/102399
if (func == NULL || dfl_ign_handler == NULL) {
return 0;
}
assert(PyLong_CheckExact(dfl_ign_handler));
if (!PyLong_CheckExact(func)) {
return 0;
}
// Assume that comparison of two PyLong objects will never fail.
return PyObject_RichCompareBool(func, dfl_ign_handler, Py_EQ) == 1;
}
#ifdef HAVE_SETITIMER
/* auxiliary function 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);
}
#endif
#if defined(HAVE_SETITIMER) || defined(HAVE_GETITIMER)
/* auxiliary functions for get/setitimer */
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 *value = PyFloat_FromDouble(double_from_timeval(&iv->it_value));
if (value == NULL) {
return NULL;
}
PyObject *interval = PyFloat_FromDouble(double_from_timeval(&iv->it_interval));
if (interval == NULL) {
Py_DECREF(value);
return NULL;
}
return _PyTuple_FromPairSteal(value, interval);
}
#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)
{
int save_errno = errno;
errno = (int) (intptr_t) data;
PyObject *exc = PyErr_GetRaisedException();
PyErr_SetFromErrno(PyExc_OSError);
PyErr_FormatUnraisable("Exception ignored while "
"trying to write to the signal wakeup fd");
PyErr_SetRaisedException(exc);
errno = save_errno;
return 0;
}
#ifdef MS_WINDOWS
static int
report_wakeup_send_error(void* data)
{
int send_errno = (int) (intptr_t) data;
PyObject *exc = PyErr_GetRaisedException();
/* PyErr_SetExcFromWindowsErr() invokes FormatMessage() which
recognizes the error codes used by both GetLastError() and
WSAGetLastError */
PyErr_SetExcFromWindowsErr(PyExc_OSError, send_errno);
PyErr_FormatUnraisable("Exception ignored while "
"trying to send to the signal wakeup fd");
PyErr_SetRaisedException(exc);
return 0;
}
#endif /* MS_WINDOWS */
static void
trip_signal(int sig_num)
{
_Py_atomic_store_int(&Handlers[sig_num].tripped, 1);
/* Set is_tripped after setting .tripped, as it gets
cleared in PyErr_CheckSignals() before .tripped. */
_Py_atomic_store_int(&is_tripped, 1);
_PyEval_SignalReceived();
/* 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 = wakeup.fd;
if (fd != INVALID_FD) {
PyInterpreterState *interp = _PyInterpreterState_Main();
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,
_Py_PENDING_MAINTHREADONLY);
}
}
}
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,
_Py_PENDING_MAINTHREADONLY);
}
}
}
}
}
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) {
signal_state_t *state = &signal_global_state;
SetEvent((HANDLE)state->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);
}
// If the current thread can handle signals, handle immediately
// the raised signal.
if (PyErr_CheckSignals()) {
return NULL;
}
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=99ce4035ec56ffc1]*/
{
_signal_module_state *modstate = get_signal_state(module);
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 >= Py_NSIG) {
_PyErr_SetString(tstate, PyExc_ValueError,
"signal number out of range");
return NULL;
}
if (PyCallable_Check(handler)) {
func = signal_handler;
} else if (compare_handler(handler, modstate->ignore_handler)) {
func = SIG_IGN;
} else if (compare_handler(handler, modstate->default_handler)) {
func = SIG_DFL;
} else {
_PyErr_SetString(tstate, PyExc_TypeError,
"signal handler must be signal.SIG_IGN, "
"signal.SIG_DFL, or a callable object");
return NULL;
}
/* 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);
set_handler(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 >= Py_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.
Returns the description of signal *signalnum*, such as "Interrupt"
for :const:`SIGINT`. Returns :const:`None` if *signalnum* has no
description. Raises :exc:`ValueError` if *signalnum* is invalid.
[clinic start generated code]*/
static PyObject *
signal_strsignal_impl(PyObject *module, int signalnum)
/*[clinic end generated code: output=44e12e1e3b666261 input=238b335847778bc0]*/
{
const char *res;
if (signalnum < 1 || signalnum >= Py_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 PyUnicode_FromString(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 >= Py_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
/*[clinic input]
@permit_long_summary
signal.set_wakeup_fd
fd as fdobj: object
/
*
warn_on_full_buffer: bool = True
Sets the fd to be written to (with the signal number) when a signal comes in.
A library can use this to wakeup select or poll.
The previous fd or -1 is returned.
The fd must be non-blocking.
[clinic start generated code]*/
static PyObject *
signal_set_wakeup_fd_impl(PyObject *module, PyObject *fdobj,
int warn_on_full_buffer)
/*[clinic end generated code: output=2280d72dd2a54c4f input=1b914d48079e9274]*/
{
struct _Py_stat_struct status;
#ifdef MS_WINDOWS
SOCKET_T sockfd, old_sockfd;
int res;
int res_size = sizeof res;
PyObject *mod;
int is_socket;
sockfd = PyLong_AsSocket_t(fdobj);
if (sockfd == (SOCKET_T)(-1) && PyErr_Occurred())
return NULL;
#else
int fd = PyLong_AsInt(fdobj);
if (fd == -1 && PyErr_Occurred()) {
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_ImportModule("_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 = Py_SAFE_DOWNCAST(sockfd, SOCKET_T, int);
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
}
/* C API for the same, without all the error checking */
int
PySignal_SetWakeupFd(int fd)
{
if (fd < 0) {
fd = -1;
}
int old_fd = wakeup.fd;
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=bd9f0d2ed8614193]*/
{
_signal_module_state *modstate = get_signal_state(module);
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(modstate->itimer_error);
return NULL;
}
return itimer_retval(&old);
}
#endif // HAVE_SETITIMER
#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]*/
{
_signal_module_state *modstate = get_signal_state(module);
struct itimerval old;
if (getitimer(which, &old) != 0) {
PyErr_SetFromErrno(modstate->itimer_error);
return NULL;
}
return itimer_retval(&old);
}
#endif // HAVE_GETITIMER
#ifdef HAVE_SIGSET_T
#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 < Py_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)
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