1 | |
2 | /* Signal module -- many thanks to Lance Ellinghaus */ |
3 | |
4 | /* XXX Signals should be recorded per thread, now we have thread state. */ |
5 | |
6 | #include "Python.h" |
7 | #include "pycore_atomic.h" // _Py_atomic_int |
8 | #include "pycore_call.h" // _PyObject_Call() |
9 | #include "pycore_ceval.h" // _PyEval_SignalReceived() |
10 | #include "pycore_moduleobject.h" // _PyModule_GetState() |
11 | #include "pycore_pyerrors.h" // _PyErr_SetString() |
12 | #include "pycore_pylifecycle.h" // NSIG |
13 | #include "pycore_pystate.h" // _PyThreadState_GET() |
14 | |
15 | #ifndef MS_WINDOWS |
16 | # include "posixmodule.h" |
17 | #endif |
18 | #ifdef MS_WINDOWS |
19 | # include "socketmodule.h" /* needed for SOCKET_T */ |
20 | #endif |
21 | |
22 | #ifdef MS_WINDOWS |
23 | # include <windows.h> |
24 | # ifdef HAVE_PROCESS_H |
25 | # include <process.h> |
26 | # endif |
27 | #endif |
28 | |
29 | #ifdef HAVE_SIGNAL_H |
30 | # include <signal.h> |
31 | #endif |
32 | #ifdef HAVE_SYS_SYSCALL_H |
33 | # include <sys/syscall.h> |
34 | #endif |
35 | #ifdef HAVE_SYS_STAT_H |
36 | # include <sys/stat.h> |
37 | #endif |
38 | #ifdef HAVE_SYS_TIME_H |
39 | # include <sys/time.h> |
40 | #endif |
41 | |
42 | #if defined(HAVE_PTHREAD_SIGMASK) && !defined(HAVE_BROKEN_PTHREAD_SIGMASK) |
43 | # define PYPTHREAD_SIGMASK |
44 | #endif |
45 | |
46 | #if defined(PYPTHREAD_SIGMASK) && defined(HAVE_PTHREAD_H) |
47 | # include <pthread.h> |
48 | #endif |
49 | |
50 | #ifndef SIG_ERR |
51 | # define SIG_ERR ((PyOS_sighandler_t)(-1)) |
52 | #endif |
53 | |
54 | #include "clinic/signalmodule.c.h" |
55 | |
56 | /*[clinic input] |
57 | module signal |
58 | [clinic start generated code]*/ |
59 | /*[clinic end generated code: output=da39a3ee5e6b4b0d input=b0301a3bde5fe9d3]*/ |
60 | |
61 | #ifdef HAVE_SETSIG_T |
62 | |
63 | /*[python input] |
64 | |
65 | class sigset_t_converter(CConverter): |
66 | type = 'sigset_t' |
67 | converter = '_Py_Sigset_Converter' |
68 | |
69 | [python start generated code]*/ |
70 | /*[python end generated code: output=da39a3ee5e6b4b0d input=b5689d14466b6823]*/ |
71 | #endif |
72 | |
73 | /* |
74 | NOTES ON THE INTERACTION BETWEEN SIGNALS AND THREADS |
75 | |
76 | We want the following semantics: |
77 | |
78 | - only the main thread can set a signal handler |
79 | - only the main thread runs the signal handler |
80 | - signals can be delivered to any thread |
81 | - any thread can get a signal handler |
82 | |
83 | I.e. we don't support "synchronous signals" like SIGFPE (catching |
84 | this doesn't make much sense in Python anyway) nor do we support |
85 | signals as a means of inter-thread communication, since not all |
86 | thread implementations support that (at least our thread library |
87 | doesn't). |
88 | |
89 | We still have the problem that in some implementations signals |
90 | generated by the keyboard (e.g. SIGINT) are delivered to all |
91 | threads (e.g. SGI), while in others (e.g. Solaris) such signals are |
92 | delivered to one random thread. On Linux, signals are delivered to |
93 | the main thread (unless the main thread is blocking the signal, for |
94 | example because it's already handling the same signal). Since we |
95 | allow signals to be delivered to any thread, this works fine. The |
96 | only oddity is that the thread executing the Python signal handler |
97 | may not be the thread that received the signal. |
98 | */ |
99 | |
100 | static volatile struct { |
101 | _Py_atomic_int tripped; |
102 | /* func is atomic to ensure that PyErr_SetInterrupt is async-signal-safe |
103 | * (even though it would probably be otherwise, anyway). |
104 | */ |
105 | _Py_atomic_address func; |
106 | } Handlers[NSIG]; |
107 | |
108 | #ifdef MS_WINDOWS |
109 | #define INVALID_FD ((SOCKET_T)-1) |
110 | |
111 | static volatile struct { |
112 | SOCKET_T fd; |
113 | int warn_on_full_buffer; |
114 | int use_send; |
115 | } wakeup = {.fd = INVALID_FD, .warn_on_full_buffer = 1, .use_send = 0}; |
116 | #else |
117 | #define INVALID_FD (-1) |
118 | static volatile struct { |
119 | #ifdef __VXWORKS__ |
120 | int fd; |
121 | #else |
122 | sig_atomic_t fd; |
123 | #endif |
124 | int warn_on_full_buffer; |
125 | } wakeup = {.fd = INVALID_FD, .warn_on_full_buffer = 1}; |
126 | #endif |
127 | |
128 | /* Speed up sigcheck() when none tripped */ |
129 | static _Py_atomic_int is_tripped; |
130 | |
131 | typedef struct { |
132 | PyObject *default_handler; |
133 | PyObject *ignore_handler; |
134 | #ifdef MS_WINDOWS |
135 | HANDLE sigint_event; |
136 | #endif |
137 | } signal_state_t; |
138 | |
139 | // State shared by all Python interpreters |
140 | static signal_state_t signal_global_state = {0}; |
141 | |
142 | #if defined(HAVE_GETITIMER) || defined(HAVE_SETITIMER) |
143 | # define PYHAVE_ITIMER_ERROR |
144 | #endif |
145 | |
146 | typedef struct { |
147 | PyObject *default_handler; // borrowed ref (signal_global_state) |
148 | PyObject *ignore_handler; // borrowed ref (signal_global_state) |
149 | #ifdef PYHAVE_ITIMER_ERROR |
150 | PyObject *itimer_error; |
151 | #endif |
152 | } _signal_module_state; |
153 | |
154 | |
155 | Py_LOCAL_INLINE(PyObject *) |
156 | get_handler(int i) |
157 | { |
158 | return (PyObject *)_Py_atomic_load(&Handlers[i].func); |
159 | } |
160 | |
161 | Py_LOCAL_INLINE(void) |
162 | set_handler(int i, PyObject* func) |
163 | { |
164 | _Py_atomic_store(&Handlers[i].func, (uintptr_t)func); |
165 | } |
166 | |
167 | |
168 | static inline _signal_module_state* |
169 | get_signal_state(PyObject *module) |
170 | { |
171 | void *state = _PyModule_GetState(module); |
172 | assert(state != NULL); |
173 | return (_signal_module_state *)state; |
174 | } |
175 | |
176 | |
177 | static inline int |
178 | compare_handler(PyObject *func, PyObject *dfl_ign_handler) |
179 | { |
180 | assert(PyLong_CheckExact(dfl_ign_handler)); |
181 | if (!PyLong_CheckExact(func)) { |
182 | return 0; |
183 | } |
184 | // Assume that comparison of two PyLong objects will never fail. |
185 | return PyObject_RichCompareBool(func, dfl_ign_handler, Py_EQ) == 1; |
186 | } |
187 | |
188 | #ifdef HAVE_GETITIMER |
189 | /* auxiliary functions for setitimer */ |
190 | static int |
191 | timeval_from_double(PyObject *obj, struct timeval *tv) |
192 | { |
193 | if (obj == NULL) { |
194 | tv->tv_sec = 0; |
195 | tv->tv_usec = 0; |
196 | return 0; |
197 | } |
198 | |
199 | _PyTime_t t; |
200 | if (_PyTime_FromSecondsObject(&t, obj, _PyTime_ROUND_CEILING) < 0) { |
201 | return -1; |
202 | } |
203 | return _PyTime_AsTimeval(t, tv, _PyTime_ROUND_CEILING); |
204 | } |
205 | |
206 | Py_LOCAL_INLINE(double) |
207 | double_from_timeval(struct timeval *tv) |
208 | { |
209 | return tv->tv_sec + (double)(tv->tv_usec / 1000000.0); |
210 | } |
211 | |
212 | static PyObject * |
213 | itimer_retval(struct itimerval *iv) |
214 | { |
215 | PyObject *r, *v; |
216 | |
217 | r = PyTuple_New(2); |
218 | if (r == NULL) |
219 | return NULL; |
220 | |
221 | if(!(v = PyFloat_FromDouble(double_from_timeval(&iv->it_value)))) { |
222 | Py_DECREF(r); |
223 | return NULL; |
224 | } |
225 | |
226 | PyTuple_SET_ITEM(r, 0, v); |
227 | |
228 | if(!(v = PyFloat_FromDouble(double_from_timeval(&iv->it_interval)))) { |
229 | Py_DECREF(r); |
230 | return NULL; |
231 | } |
232 | |
233 | PyTuple_SET_ITEM(r, 1, v); |
234 | |
235 | return r; |
236 | } |
237 | #endif |
238 | |
239 | /*[clinic input] |
240 | signal.default_int_handler |
241 | signalnum: int |
242 | frame: object |
243 | / |
244 | |
245 | The default handler for SIGINT installed by Python. |
246 | |
247 | It raises KeyboardInterrupt. |
248 | [clinic start generated code]*/ |
249 | |
250 | static PyObject * |
251 | signal_default_int_handler_impl(PyObject *module, int signalnum, |
252 | PyObject *frame) |
253 | /*[clinic end generated code: output=bb11c2eb115ace4e input=efcd4a56a207acfd]*/ |
254 | { |
255 | PyErr_SetNone(PyExc_KeyboardInterrupt); |
256 | return NULL; |
257 | } |
258 | |
259 | |
260 | static int |
261 | report_wakeup_write_error(void *data) |
262 | { |
263 | PyObject *exc, *val, *tb; |
264 | int save_errno = errno; |
265 | errno = (int) (intptr_t) data; |
266 | PyErr_Fetch(&exc, &val, &tb); |
267 | PyErr_SetFromErrno(PyExc_OSError); |
268 | PySys_WriteStderr("Exception ignored when trying to write to the " |
269 | "signal wakeup fd:\n" ); |
270 | PyErr_WriteUnraisable(NULL); |
271 | PyErr_Restore(exc, val, tb); |
272 | errno = save_errno; |
273 | return 0; |
274 | } |
275 | |
276 | #ifdef MS_WINDOWS |
277 | static int |
278 | report_wakeup_send_error(void* data) |
279 | { |
280 | PyObject *exc, *val, *tb; |
281 | PyErr_Fetch(&exc, &val, &tb); |
282 | /* PyErr_SetExcFromWindowsErr() invokes FormatMessage() which |
283 | recognizes the error codes used by both GetLastError() and |
284 | WSAGetLastError */ |
285 | PyErr_SetExcFromWindowsErr(PyExc_OSError, (int) (intptr_t) data); |
286 | PySys_WriteStderr("Exception ignored when trying to send to the " |
287 | "signal wakeup fd:\n" ); |
288 | PyErr_WriteUnraisable(NULL); |
289 | PyErr_Restore(exc, val, tb); |
290 | return 0; |
291 | } |
292 | #endif /* MS_WINDOWS */ |
293 | |
294 | static void |
295 | trip_signal(int sig_num) |
296 | { |
297 | _Py_atomic_store_relaxed(&Handlers[sig_num].tripped, 1); |
298 | |
299 | /* Set is_tripped after setting .tripped, as it gets |
300 | cleared in PyErr_CheckSignals() before .tripped. */ |
301 | _Py_atomic_store(&is_tripped, 1); |
302 | |
303 | /* Signals are always handled by the main interpreter */ |
304 | PyInterpreterState *interp = _PyRuntime.interpreters.main; |
305 | |
306 | /* Notify ceval.c */ |
307 | _PyEval_SignalReceived(interp); |
308 | |
309 | /* And then write to the wakeup fd *after* setting all the globals and |
310 | doing the _PyEval_SignalReceived. We used to write to the wakeup fd |
311 | and then set the flag, but this allowed the following sequence of events |
312 | (especially on windows, where trip_signal may run in a new thread): |
313 | |
314 | - main thread blocks on select([wakeup.fd], ...) |
315 | - signal arrives |
316 | - trip_signal writes to the wakeup fd |
317 | - the main thread wakes up |
318 | - the main thread checks the signal flags, sees that they're unset |
319 | - the main thread empties the wakeup fd |
320 | - the main thread goes back to sleep |
321 | - trip_signal sets the flags to request the Python-level signal handler |
322 | be run |
323 | - the main thread doesn't notice, because it's asleep |
324 | |
325 | See bpo-30038 for more details. |
326 | */ |
327 | |
328 | int fd; |
329 | #ifdef MS_WINDOWS |
330 | fd = Py_SAFE_DOWNCAST(wakeup.fd, SOCKET_T, int); |
331 | #else |
332 | fd = wakeup.fd; |
333 | #endif |
334 | |
335 | if (fd != INVALID_FD) { |
336 | unsigned char byte = (unsigned char)sig_num; |
337 | #ifdef MS_WINDOWS |
338 | if (wakeup.use_send) { |
339 | Py_ssize_t rc = send(fd, &byte, 1, 0); |
340 | |
341 | if (rc < 0) { |
342 | int last_error = GetLastError(); |
343 | if (wakeup.warn_on_full_buffer || |
344 | last_error != WSAEWOULDBLOCK) |
345 | { |
346 | /* _PyEval_AddPendingCall() isn't signal-safe, but we |
347 | still use it for this exceptional case. */ |
348 | _PyEval_AddPendingCall(interp, |
349 | report_wakeup_send_error, |
350 | (void *)(intptr_t) last_error); |
351 | } |
352 | } |
353 | } |
354 | else |
355 | #endif |
356 | { |
357 | /* _Py_write_noraise() retries write() if write() is interrupted by |
358 | a signal (fails with EINTR). */ |
359 | Py_ssize_t rc = _Py_write_noraise(fd, &byte, 1); |
360 | |
361 | if (rc < 0) { |
362 | if (wakeup.warn_on_full_buffer || |
363 | (errno != EWOULDBLOCK && errno != EAGAIN)) |
364 | { |
365 | /* _PyEval_AddPendingCall() isn't signal-safe, but we |
366 | still use it for this exceptional case. */ |
367 | _PyEval_AddPendingCall(interp, |
368 | report_wakeup_write_error, |
369 | (void *)(intptr_t)errno); |
370 | } |
371 | } |
372 | } |
373 | } |
374 | } |
375 | |
376 | static void |
377 | signal_handler(int sig_num) |
378 | { |
379 | int save_errno = errno; |
380 | |
381 | trip_signal(sig_num); |
382 | |
383 | #ifndef HAVE_SIGACTION |
384 | #ifdef SIGCHLD |
385 | /* To avoid infinite recursion, this signal remains |
386 | reset until explicit re-instated. |
387 | Don't clear the 'func' field as it is our pointer |
388 | to the Python handler... */ |
389 | if (sig_num != SIGCHLD) |
390 | #endif |
391 | /* If the handler was not set up with sigaction, reinstall it. See |
392 | * Python/pylifecycle.c for the implementation of PyOS_setsig which |
393 | * makes this true. See also issue8354. */ |
394 | PyOS_setsig(sig_num, signal_handler); |
395 | #endif |
396 | |
397 | /* Issue #10311: asynchronously executing signal handlers should not |
398 | mutate errno under the feet of unsuspecting C code. */ |
399 | errno = save_errno; |
400 | |
401 | #ifdef MS_WINDOWS |
402 | if (sig_num == SIGINT) { |
403 | signal_state_t *state = &signal_global_state; |
404 | SetEvent(state->sigint_event); |
405 | } |
406 | #endif |
407 | } |
408 | |
409 | |
410 | #ifdef HAVE_ALARM |
411 | |
412 | /*[clinic input] |
413 | signal.alarm -> long |
414 | |
415 | seconds: int |
416 | / |
417 | |
418 | Arrange for SIGALRM to arrive after the given number of seconds. |
419 | [clinic start generated code]*/ |
420 | |
421 | static long |
422 | signal_alarm_impl(PyObject *module, int seconds) |
423 | /*[clinic end generated code: output=144232290814c298 input=0d5e97e0e6f39e86]*/ |
424 | { |
425 | /* alarm() returns the number of seconds remaining */ |
426 | return (long)alarm(seconds); |
427 | } |
428 | |
429 | #endif |
430 | |
431 | #ifdef HAVE_PAUSE |
432 | |
433 | /*[clinic input] |
434 | signal.pause |
435 | |
436 | Wait until a signal arrives. |
437 | [clinic start generated code]*/ |
438 | |
439 | static PyObject * |
440 | signal_pause_impl(PyObject *module) |
441 | /*[clinic end generated code: output=391656788b3c3929 input=f03de0f875752062]*/ |
442 | { |
443 | Py_BEGIN_ALLOW_THREADS |
444 | (void)pause(); |
445 | Py_END_ALLOW_THREADS |
446 | /* make sure that any exceptions that got raised are propagated |
447 | * back into Python |
448 | */ |
449 | if (PyErr_CheckSignals()) |
450 | return NULL; |
451 | |
452 | Py_RETURN_NONE; |
453 | } |
454 | |
455 | #endif |
456 | |
457 | /*[clinic input] |
458 | signal.raise_signal |
459 | |
460 | signalnum: int |
461 | / |
462 | |
463 | Send a signal to the executing process. |
464 | [clinic start generated code]*/ |
465 | |
466 | static PyObject * |
467 | signal_raise_signal_impl(PyObject *module, int signalnum) |
468 | /*[clinic end generated code: output=e2b014220aa6111d input=e90c0f9a42358de6]*/ |
469 | { |
470 | int err; |
471 | Py_BEGIN_ALLOW_THREADS |
472 | _Py_BEGIN_SUPPRESS_IPH |
473 | err = raise(signalnum); |
474 | _Py_END_SUPPRESS_IPH |
475 | Py_END_ALLOW_THREADS |
476 | |
477 | if (err) { |
478 | return PyErr_SetFromErrno(PyExc_OSError); |
479 | } |
480 | Py_RETURN_NONE; |
481 | } |
482 | |
483 | /*[clinic input] |
484 | signal.signal |
485 | |
486 | signalnum: int |
487 | handler: object |
488 | / |
489 | |
490 | Set the action for the given signal. |
491 | |
492 | The action can be SIG_DFL, SIG_IGN, or a callable Python object. |
493 | The previous action is returned. See getsignal() for possible return values. |
494 | |
495 | *** IMPORTANT NOTICE *** |
496 | A signal handler function is called with two arguments: |
497 | the first is the signal number, the second is the interrupted stack frame. |
498 | [clinic start generated code]*/ |
499 | |
500 | static PyObject * |
501 | signal_signal_impl(PyObject *module, int signalnum, PyObject *handler) |
502 | /*[clinic end generated code: output=b44cfda43780f3a1 input=deee84af5fa0432c]*/ |
503 | { |
504 | _signal_module_state *modstate = get_signal_state(module); |
505 | PyObject *old_handler; |
506 | void (*func)(int); |
507 | #ifdef MS_WINDOWS |
508 | /* Validate that signalnum is one of the allowable signals */ |
509 | switch (signalnum) { |
510 | case SIGABRT: break; |
511 | #ifdef SIGBREAK |
512 | /* Issue #10003: SIGBREAK is not documented as permitted, but works |
513 | and corresponds to CTRL_BREAK_EVENT. */ |
514 | case SIGBREAK: break; |
515 | #endif |
516 | case SIGFPE: break; |
517 | case SIGILL: break; |
518 | case SIGINT: break; |
519 | case SIGSEGV: break; |
520 | case SIGTERM: break; |
521 | default: |
522 | PyErr_SetString(PyExc_ValueError, "invalid signal value" ); |
523 | return NULL; |
524 | } |
525 | #endif |
526 | |
527 | PyThreadState *tstate = _PyThreadState_GET(); |
528 | if (!_Py_ThreadCanHandleSignals(tstate->interp)) { |
529 | _PyErr_SetString(tstate, PyExc_ValueError, |
530 | "signal only works in main thread " |
531 | "of the main interpreter" ); |
532 | return NULL; |
533 | } |
534 | if (signalnum < 1 || signalnum >= NSIG) { |
535 | _PyErr_SetString(tstate, PyExc_ValueError, |
536 | "signal number out of range" ); |
537 | return NULL; |
538 | } |
539 | if (PyCallable_Check(handler)) { |
540 | func = signal_handler; |
541 | } else if (compare_handler(handler, modstate->ignore_handler)) { |
542 | func = SIG_IGN; |
543 | } else if (compare_handler(handler, modstate->default_handler)) { |
544 | func = SIG_DFL; |
545 | } else { |
546 | _PyErr_SetString(tstate, PyExc_TypeError, |
547 | "signal handler must be signal.SIG_IGN, " |
548 | "signal.SIG_DFL, or a callable object" ); |
549 | return NULL; |
550 | } |
551 | |
552 | /* Check for pending signals before changing signal handler */ |
553 | if (_PyErr_CheckSignalsTstate(tstate)) { |
554 | return NULL; |
555 | } |
556 | if (PyOS_setsig(signalnum, func) == SIG_ERR) { |
557 | PyErr_SetFromErrno(PyExc_OSError); |
558 | return NULL; |
559 | } |
560 | |
561 | old_handler = get_handler(signalnum); |
562 | set_handler(signalnum, Py_NewRef(handler)); |
563 | |
564 | if (old_handler != NULL) { |
565 | return old_handler; |
566 | } |
567 | else { |
568 | Py_RETURN_NONE; |
569 | } |
570 | } |
571 | |
572 | |
573 | /*[clinic input] |
574 | signal.getsignal |
575 | |
576 | signalnum: int |
577 | / |
578 | |
579 | Return the current action for the given signal. |
580 | |
581 | The return value can be: |
582 | SIG_IGN -- if the signal is being ignored |
583 | SIG_DFL -- if the default action for the signal is in effect |
584 | None -- if an unknown handler is in effect |
585 | anything else -- the callable Python object used as a handler |
586 | [clinic start generated code]*/ |
587 | |
588 | static PyObject * |
589 | signal_getsignal_impl(PyObject *module, int signalnum) |
590 | /*[clinic end generated code: output=35b3e0e796fd555e input=ac23a00f19dfa509]*/ |
591 | { |
592 | PyObject *old_handler; |
593 | if (signalnum < 1 || signalnum >= NSIG) { |
594 | PyErr_SetString(PyExc_ValueError, |
595 | "signal number out of range" ); |
596 | return NULL; |
597 | } |
598 | old_handler = get_handler(signalnum); |
599 | if (old_handler != NULL) { |
600 | return Py_NewRef(old_handler); |
601 | } |
602 | else { |
603 | Py_RETURN_NONE; |
604 | } |
605 | } |
606 | |
607 | |
608 | /*[clinic input] |
609 | signal.strsignal |
610 | |
611 | signalnum: int |
612 | / |
613 | |
614 | Return the system description of the given signal. |
615 | |
616 | The return values can be such as "Interrupt", "Segmentation fault", etc. |
617 | Returns None if the signal is not recognized. |
618 | [clinic start generated code]*/ |
619 | |
620 | static PyObject * |
621 | signal_strsignal_impl(PyObject *module, int signalnum) |
622 | /*[clinic end generated code: output=44e12e1e3b666261 input=b77914b03f856c74]*/ |
623 | { |
624 | char *res; |
625 | |
626 | if (signalnum < 1 || signalnum >= NSIG) { |
627 | PyErr_SetString(PyExc_ValueError, |
628 | "signal number out of range" ); |
629 | return NULL; |
630 | } |
631 | |
632 | #ifndef HAVE_STRSIGNAL |
633 | switch (signalnum) { |
634 | /* Though being a UNIX, HP-UX does not provide strsignal(3). */ |
635 | #ifndef MS_WINDOWS |
636 | case SIGHUP: |
637 | res = "Hangup" ; |
638 | break; |
639 | case SIGALRM: |
640 | res = "Alarm clock" ; |
641 | break; |
642 | case SIGPIPE: |
643 | res = "Broken pipe" ; |
644 | break; |
645 | case SIGQUIT: |
646 | res = "Quit" ; |
647 | break; |
648 | case SIGCHLD: |
649 | res = "Child exited" ; |
650 | break; |
651 | #endif |
652 | /* Custom redefinition of POSIX signals allowed on Windows. */ |
653 | case SIGINT: |
654 | res = "Interrupt" ; |
655 | break; |
656 | case SIGILL: |
657 | res = "Illegal instruction" ; |
658 | break; |
659 | case SIGABRT: |
660 | res = "Aborted" ; |
661 | break; |
662 | case SIGFPE: |
663 | res = "Floating point exception" ; |
664 | break; |
665 | case SIGSEGV: |
666 | res = "Segmentation fault" ; |
667 | break; |
668 | case SIGTERM: |
669 | res = "Terminated" ; |
670 | break; |
671 | default: |
672 | Py_RETURN_NONE; |
673 | } |
674 | #else |
675 | errno = 0; |
676 | res = strsignal(signalnum); |
677 | |
678 | if (errno || res == NULL || strstr(res, "Unknown signal" ) != NULL) |
679 | Py_RETURN_NONE; |
680 | #endif |
681 | |
682 | return Py_BuildValue("s" , res); |
683 | } |
684 | |
685 | #ifdef HAVE_SIGINTERRUPT |
686 | |
687 | /*[clinic input] |
688 | signal.siginterrupt |
689 | |
690 | signalnum: int |
691 | flag: int |
692 | / |
693 | |
694 | Change system call restart behaviour. |
695 | |
696 | If flag is False, system calls will be restarted when interrupted by |
697 | signal sig, else system calls will be interrupted. |
698 | [clinic start generated code]*/ |
699 | |
700 | static PyObject * |
701 | signal_siginterrupt_impl(PyObject *module, int signalnum, int flag) |
702 | /*[clinic end generated code: output=063816243d85dd19 input=4160acacca3e2099]*/ |
703 | { |
704 | if (signalnum < 1 || signalnum >= NSIG) { |
705 | PyErr_SetString(PyExc_ValueError, |
706 | "signal number out of range" ); |
707 | return NULL; |
708 | } |
709 | #ifdef HAVE_SIGACTION |
710 | struct sigaction act; |
711 | (void) sigaction(signalnum, NULL, &act); |
712 | if (flag) { |
713 | act.sa_flags &= ~SA_RESTART; |
714 | } |
715 | else { |
716 | act.sa_flags |= SA_RESTART; |
717 | } |
718 | if (sigaction(signalnum, &act, NULL) < 0) { |
719 | #else |
720 | if (siginterrupt(signalnum, flag) < 0) { |
721 | #endif |
722 | PyErr_SetFromErrno(PyExc_OSError); |
723 | return NULL; |
724 | } |
725 | Py_RETURN_NONE; |
726 | } |
727 | |
728 | #endif |
729 | |
730 | |
731 | static PyObject* |
732 | signal_set_wakeup_fd(PyObject *self, PyObject *args, PyObject *kwds) |
733 | { |
734 | struct _Py_stat_struct status; |
735 | static char *kwlist[] = { |
736 | "" , "warn_on_full_buffer" , NULL, |
737 | }; |
738 | int warn_on_full_buffer = 1; |
739 | #ifdef MS_WINDOWS |
740 | PyObject *fdobj; |
741 | SOCKET_T sockfd, old_sockfd; |
742 | int res; |
743 | int res_size = sizeof res; |
744 | PyObject *mod; |
745 | int is_socket; |
746 | |
747 | if (!PyArg_ParseTupleAndKeywords(args, kwds, "O|$p:set_wakeup_fd" , kwlist, |
748 | &fdobj, &warn_on_full_buffer)) |
749 | return NULL; |
750 | |
751 | sockfd = PyLong_AsSocket_t(fdobj); |
752 | if (sockfd == (SOCKET_T)(-1) && PyErr_Occurred()) |
753 | return NULL; |
754 | #else |
755 | int fd; |
756 | |
757 | if (!PyArg_ParseTupleAndKeywords(args, kwds, "i|$p:set_wakeup_fd" , kwlist, |
758 | &fd, &warn_on_full_buffer)) |
759 | return NULL; |
760 | #endif |
761 | |
762 | PyThreadState *tstate = _PyThreadState_GET(); |
763 | if (!_Py_ThreadCanHandleSignals(tstate->interp)) { |
764 | _PyErr_SetString(tstate, PyExc_ValueError, |
765 | "set_wakeup_fd only works in main thread " |
766 | "of the main interpreter" ); |
767 | return NULL; |
768 | } |
769 | |
770 | #ifdef MS_WINDOWS |
771 | is_socket = 0; |
772 | if (sockfd != INVALID_FD) { |
773 | /* Import the _socket module to call WSAStartup() */ |
774 | mod = PyImport_ImportModuleNoBlock("_socket" ); |
775 | if (mod == NULL) |
776 | return NULL; |
777 | Py_DECREF(mod); |
778 | |
779 | /* test the socket */ |
780 | if (getsockopt(sockfd, SOL_SOCKET, SO_ERROR, |
781 | (char *)&res, &res_size) != 0) { |
782 | int fd, err; |
783 | |
784 | err = WSAGetLastError(); |
785 | if (err != WSAENOTSOCK) { |
786 | PyErr_SetExcFromWindowsErr(PyExc_OSError, err); |
787 | return NULL; |
788 | } |
789 | |
790 | fd = (int)sockfd; |
791 | if ((SOCKET_T)fd != sockfd) { |
792 | _PyErr_SetString(tstate, PyExc_ValueError, "invalid fd" ); |
793 | return NULL; |
794 | } |
795 | |
796 | if (_Py_fstat(fd, &status) != 0) { |
797 | return NULL; |
798 | } |
799 | |
800 | /* on Windows, a file cannot be set to non-blocking mode */ |
801 | } |
802 | else { |
803 | is_socket = 1; |
804 | |
805 | /* Windows does not provide a function to test if a socket |
806 | is in non-blocking mode */ |
807 | } |
808 | } |
809 | |
810 | old_sockfd = wakeup.fd; |
811 | wakeup.fd = sockfd; |
812 | wakeup.warn_on_full_buffer = warn_on_full_buffer; |
813 | wakeup.use_send = is_socket; |
814 | |
815 | if (old_sockfd != INVALID_FD) |
816 | return PyLong_FromSocket_t(old_sockfd); |
817 | else |
818 | return PyLong_FromLong(-1); |
819 | #else |
820 | if (fd != -1) { |
821 | int blocking; |
822 | |
823 | if (_Py_fstat(fd, &status) != 0) |
824 | return NULL; |
825 | |
826 | blocking = _Py_get_blocking(fd); |
827 | if (blocking < 0) |
828 | return NULL; |
829 | if (blocking) { |
830 | _PyErr_Format(tstate, PyExc_ValueError, |
831 | "the fd %i must be in non-blocking mode" , |
832 | fd); |
833 | return NULL; |
834 | } |
835 | } |
836 | |
837 | int old_fd = wakeup.fd; |
838 | wakeup.fd = fd; |
839 | wakeup.warn_on_full_buffer = warn_on_full_buffer; |
840 | |
841 | return PyLong_FromLong(old_fd); |
842 | #endif |
843 | } |
844 | |
845 | PyDoc_STRVAR(set_wakeup_fd_doc, |
846 | "set_wakeup_fd(fd, *, warn_on_full_buffer=True) -> fd\n\ |
847 | \n\ |
848 | Sets the fd to be written to (with the signal number) when a signal\n\ |
849 | comes in. A library can use this to wakeup select or poll.\n\ |
850 | The previous fd or -1 is returned.\n\ |
851 | \n\ |
852 | The fd must be non-blocking." ); |
853 | |
854 | /* C API for the same, without all the error checking */ |
855 | int |
856 | PySignal_SetWakeupFd(int fd) |
857 | { |
858 | if (fd < 0) { |
859 | fd = -1; |
860 | } |
861 | |
862 | #ifdef MS_WINDOWS |
863 | int old_fd = Py_SAFE_DOWNCAST(wakeup.fd, SOCKET_T, int); |
864 | #else |
865 | int old_fd = wakeup.fd; |
866 | #endif |
867 | wakeup.fd = fd; |
868 | wakeup.warn_on_full_buffer = 1; |
869 | return old_fd; |
870 | } |
871 | |
872 | |
873 | #ifdef HAVE_SETITIMER |
874 | /*[clinic input] |
875 | signal.setitimer |
876 | |
877 | which: int |
878 | seconds: object |
879 | interval: object(c_default="NULL") = 0.0 |
880 | / |
881 | |
882 | Sets given itimer (one of ITIMER_REAL, ITIMER_VIRTUAL or ITIMER_PROF). |
883 | |
884 | The timer will fire after value seconds and after that every interval seconds. |
885 | The itimer can be cleared by setting seconds to zero. |
886 | |
887 | Returns old values as a tuple: (delay, interval). |
888 | [clinic start generated code]*/ |
889 | |
890 | static PyObject * |
891 | signal_setitimer_impl(PyObject *module, int which, PyObject *seconds, |
892 | PyObject *interval) |
893 | /*[clinic end generated code: output=65f9dcbddc35527b input=de43daf194e6f66f]*/ |
894 | { |
895 | _signal_module_state *modstate = get_signal_state(module); |
896 | |
897 | struct itimerval new; |
898 | if (timeval_from_double(seconds, &new.it_value) < 0) { |
899 | return NULL; |
900 | } |
901 | if (timeval_from_double(interval, &new.it_interval) < 0) { |
902 | return NULL; |
903 | } |
904 | |
905 | /* Let OS check "which" value */ |
906 | struct itimerval old; |
907 | if (setitimer(which, &new, &old) != 0) { |
908 | PyErr_SetFromErrno(modstate->itimer_error); |
909 | return NULL; |
910 | } |
911 | |
912 | return itimer_retval(&old); |
913 | } |
914 | #endif // HAVE_SETITIMER |
915 | |
916 | |
917 | #ifdef HAVE_GETITIMER |
918 | /*[clinic input] |
919 | signal.getitimer |
920 | |
921 | which: int |
922 | / |
923 | |
924 | Returns current value of given itimer. |
925 | [clinic start generated code]*/ |
926 | |
927 | static PyObject * |
928 | signal_getitimer_impl(PyObject *module, int which) |
929 | /*[clinic end generated code: output=9e053175d517db40 input=f7d21d38f3490627]*/ |
930 | { |
931 | _signal_module_state *modstate = get_signal_state(module); |
932 | |
933 | struct itimerval old; |
934 | if (getitimer(which, &old) != 0) { |
935 | PyErr_SetFromErrno(modstate->itimer_error); |
936 | return NULL; |
937 | } |
938 | |
939 | return itimer_retval(&old); |
940 | } |
941 | #endif // HAVE_GETITIMER |
942 | |
943 | |
944 | #ifdef HAVE_SIGSET_T |
945 | #if defined(PYPTHREAD_SIGMASK) || defined(HAVE_SIGPENDING) |
946 | static PyObject* |
947 | sigset_to_set(sigset_t mask) |
948 | { |
949 | PyObject *signum, *result; |
950 | int sig; |
951 | |
952 | result = PySet_New(0); |
953 | if (result == NULL) |
954 | return NULL; |
955 | |
956 | for (sig = 1; sig < NSIG; sig++) { |
957 | if (sigismember(&mask, sig) != 1) |
958 | continue; |
959 | |
960 | /* Handle the case where it is a member by adding the signal to |
961 | the result list. Ignore the other cases because they mean the |
962 | signal isn't a member of the mask or the signal was invalid, |
963 | and an invalid signal must have been our fault in constructing |
964 | the loop boundaries. */ |
965 | signum = PyLong_FromLong(sig); |
966 | if (signum == NULL) { |
967 | Py_DECREF(result); |
968 | return NULL; |
969 | } |
970 | if (PySet_Add(result, signum) == -1) { |
971 | Py_DECREF(signum); |
972 | Py_DECREF(result); |
973 | return NULL; |
974 | } |
975 | Py_DECREF(signum); |
976 | } |
977 | return result; |
978 | } |
979 | #endif |
980 | |
981 | #ifdef PYPTHREAD_SIGMASK |
982 | |
983 | /*[clinic input] |
984 | signal.pthread_sigmask |
985 | |
986 | how: int |
987 | mask: sigset_t |
988 | / |
989 | |
990 | Fetch and/or change the signal mask of the calling thread. |
991 | [clinic start generated code]*/ |
992 | |
993 | static PyObject * |
994 | signal_pthread_sigmask_impl(PyObject *module, int how, sigset_t mask) |
995 | /*[clinic end generated code: output=0562c0fb192981a8 input=85bcebda442fa77f]*/ |
996 | { |
997 | sigset_t previous; |
998 | int err; |
999 | |
1000 | err = pthread_sigmask(how, &mask, &previous); |
1001 | if (err != 0) { |
1002 | errno = err; |
1003 | PyErr_SetFromErrno(PyExc_OSError); |
1004 | return NULL; |
1005 | } |
1006 | |
1007 | /* if signals was unblocked, signal handlers have been called */ |
1008 | if (PyErr_CheckSignals()) |
1009 | return NULL; |
1010 | |
1011 | return sigset_to_set(previous); |
1012 | } |
1013 | |
1014 | #endif /* #ifdef PYPTHREAD_SIGMASK */ |
1015 | |
1016 | |
1017 | #ifdef HAVE_SIGPENDING |
1018 | |
1019 | /*[clinic input] |
1020 | signal.sigpending |
1021 | |
1022 | Examine pending signals. |
1023 | |
1024 | Returns a set of signal numbers that are pending for delivery to |
1025 | the calling thread. |
1026 | [clinic start generated code]*/ |
1027 | |
1028 | static PyObject * |
1029 | signal_sigpending_impl(PyObject *module) |
1030 | /*[clinic end generated code: output=53375ffe89325022 input=e0036c016f874e29]*/ |
1031 | { |
1032 | int err; |
1033 | sigset_t mask; |
1034 | err = sigpending(&mask); |
1035 | if (err) |
1036 | return PyErr_SetFromErrno(PyExc_OSError); |
1037 | return sigset_to_set(mask); |
1038 | } |
1039 | |
1040 | #endif /* #ifdef HAVE_SIGPENDING */ |
1041 | |
1042 | |
1043 | #ifdef HAVE_SIGWAIT |
1044 | |
1045 | /*[clinic input] |
1046 | signal.sigwait |
1047 | |
1048 | sigset: sigset_t |
1049 | / |
1050 | |
1051 | Wait for a signal. |
1052 | |
1053 | Suspend execution of the calling thread until the delivery of one of the |
1054 | signals specified in the signal set sigset. The function accepts the signal |
1055 | and returns the signal number. |
1056 | [clinic start generated code]*/ |
1057 | |
1058 | static PyObject * |
1059 | signal_sigwait_impl(PyObject *module, sigset_t sigset) |
1060 | /*[clinic end generated code: output=f43770699d682f96 input=a6fbd47b1086d119]*/ |
1061 | { |
1062 | int err, signum; |
1063 | |
1064 | Py_BEGIN_ALLOW_THREADS |
1065 | err = sigwait(&sigset, &signum); |
1066 | Py_END_ALLOW_THREADS |
1067 | if (err) { |
1068 | errno = err; |
1069 | return PyErr_SetFromErrno(PyExc_OSError); |
1070 | } |
1071 | |
1072 | return PyLong_FromLong(signum); |
1073 | } |
1074 | |
1075 | #endif /* #ifdef HAVE_SIGWAIT */ |
1076 | #endif /* #ifdef HAVE_SIGSET_T */ |
1077 | |
1078 | #if (defined(HAVE_SIGFILLSET) && defined(HAVE_SIGSET_T)) || defined(MS_WINDOWS) |
1079 | |
1080 | /*[clinic input] |
1081 | signal.valid_signals |
1082 | |
1083 | Return a set of valid signal numbers on this platform. |
1084 | |
1085 | The signal numbers returned by this function can be safely passed to |
1086 | functions like `pthread_sigmask`. |
1087 | [clinic start generated code]*/ |
1088 | |
1089 | static PyObject * |
1090 | signal_valid_signals_impl(PyObject *module) |
1091 | /*[clinic end generated code: output=1609cffbcfcf1314 input=86a3717ff25288f2]*/ |
1092 | { |
1093 | #ifdef MS_WINDOWS |
1094 | #ifdef SIGBREAK |
1095 | PyObject *tup = Py_BuildValue("(iiiiiii)" , SIGABRT, SIGBREAK, SIGFPE, |
1096 | SIGILL, SIGINT, SIGSEGV, SIGTERM); |
1097 | #else |
1098 | PyObject *tup = Py_BuildValue("(iiiiii)" , SIGABRT, SIGFPE, SIGILL, |
1099 | SIGINT, SIGSEGV, SIGTERM); |
1100 | #endif |
1101 | if (tup == NULL) { |
1102 | return NULL; |
1103 | } |
1104 | PyObject *set = PySet_New(tup); |
1105 | Py_DECREF(tup); |
1106 | return set; |
1107 | #else |
1108 | sigset_t mask; |
1109 | if (sigemptyset(&mask) || sigfillset(&mask)) { |
1110 | return PyErr_SetFromErrno(PyExc_OSError); |
1111 | } |
1112 | return sigset_to_set(mask); |
1113 | #endif |
1114 | } |
1115 | |
1116 | #endif /* #if (defined(HAVE_SIGFILLSET) && defined(HAVE_SIGSET_T)) || defined(MS_WINDOWS) */ |
1117 | |
1118 | |
1119 | |
1120 | #if defined(HAVE_SIGWAITINFO) || defined(HAVE_SIGTIMEDWAIT) |
1121 | static PyStructSequence_Field struct_siginfo_fields[] = { |
1122 | {"si_signo" , "signal number" }, |
1123 | {"si_code" , "signal code" }, |
1124 | {"si_errno" , "errno associated with this signal" }, |
1125 | {"si_pid" , "sending process ID" }, |
1126 | {"si_uid" , "real user ID of sending process" }, |
1127 | {"si_status" , "exit value or signal" }, |
1128 | {"si_band" , "band event for SIGPOLL" }, |
1129 | {0} |
1130 | }; |
1131 | |
1132 | PyDoc_STRVAR(struct_siginfo__doc__, |
1133 | "struct_siginfo: Result from sigwaitinfo or sigtimedwait.\n\n\ |
1134 | This object may be accessed either as a tuple of\n\ |
1135 | (si_signo, si_code, si_errno, si_pid, si_uid, si_status, si_band),\n\ |
1136 | or via the attributes si_signo, si_code, and so on." ); |
1137 | |
1138 | static PyStructSequence_Desc struct_siginfo_desc = { |
1139 | "signal.struct_siginfo" , /* name */ |
1140 | struct_siginfo__doc__, /* doc */ |
1141 | struct_siginfo_fields, /* fields */ |
1142 | 7 /* n_in_sequence */ |
1143 | }; |
1144 | |
1145 | static PyTypeObject SiginfoType; |
1146 | |
1147 | static PyObject * |
1148 | fill_siginfo(siginfo_t *si) |
1149 | { |
1150 | PyObject *result = PyStructSequence_New(&SiginfoType); |
1151 | if (!result) |
1152 | return NULL; |
1153 | |
1154 | PyStructSequence_SET_ITEM(result, 0, PyLong_FromLong((long)(si->si_signo))); |
1155 | PyStructSequence_SET_ITEM(result, 1, PyLong_FromLong((long)(si->si_code))); |
1156 | #ifdef __VXWORKS__ |
1157 | PyStructSequence_SET_ITEM(result, 2, PyLong_FromLong(0L)); |
1158 | PyStructSequence_SET_ITEM(result, 3, PyLong_FromLong(0L)); |
1159 | PyStructSequence_SET_ITEM(result, 4, PyLong_FromLong(0L)); |
1160 | PyStructSequence_SET_ITEM(result, 5, PyLong_FromLong(0L)); |
1161 | #else |
1162 | PyStructSequence_SET_ITEM(result, 2, PyLong_FromLong((long)(si->si_errno))); |
1163 | PyStructSequence_SET_ITEM(result, 3, PyLong_FromPid(si->si_pid)); |
1164 | PyStructSequence_SET_ITEM(result, 4, _PyLong_FromUid(si->si_uid)); |
1165 | PyStructSequence_SET_ITEM(result, 5, |
1166 | PyLong_FromLong((long)(si->si_status))); |
1167 | #endif |
1168 | #ifdef HAVE_SIGINFO_T_SI_BAND |
1169 | PyStructSequence_SET_ITEM(result, 6, PyLong_FromLong(si->si_band)); |
1170 | #else |
1171 | PyStructSequence_SET_ITEM(result, 6, PyLong_FromLong(0L)); |
1172 | #endif |
1173 | if (PyErr_Occurred()) { |
1174 | Py_DECREF(result); |
1175 | return NULL; |
1176 | } |
1177 | |
1178 | return result; |
1179 | } |
1180 | #endif |
1181 | |
1182 | #ifdef HAVE_SIGSET_T |
1183 | #ifdef HAVE_SIGWAITINFO |
1184 | |
1185 | /*[clinic input] |
1186 | signal.sigwaitinfo |
1187 | |
1188 | sigset: sigset_t |
1189 | / |
1190 | |
1191 | Wait synchronously until one of the signals in *sigset* is delivered. |
1192 | |
1193 | Returns a struct_siginfo containing information about the signal. |
1194 | [clinic start generated code]*/ |
1195 | |
1196 | static PyObject * |
1197 | signal_sigwaitinfo_impl(PyObject *module, sigset_t sigset) |
1198 | /*[clinic end generated code: output=1eb2f1fa236fdbca input=3d1a7e1f27fc664c]*/ |
1199 | { |
1200 | siginfo_t si; |
1201 | int err; |
1202 | int async_err = 0; |
1203 | |
1204 | do { |
1205 | Py_BEGIN_ALLOW_THREADS |
1206 | err = sigwaitinfo(&sigset, &si); |
1207 | Py_END_ALLOW_THREADS |
1208 | } while (err == -1 |
1209 | && errno == EINTR && !(async_err = PyErr_CheckSignals())); |
1210 | if (err == -1) |
1211 | return (!async_err) ? PyErr_SetFromErrno(PyExc_OSError) : NULL; |
1212 | |
1213 | return fill_siginfo(&si); |
1214 | } |
1215 | |
1216 | #endif /* #ifdef HAVE_SIGWAITINFO */ |
1217 | |
1218 | #ifdef HAVE_SIGTIMEDWAIT |
1219 | |
1220 | /*[clinic input] |
1221 | signal.sigtimedwait |
1222 | |
1223 | sigset: sigset_t |
1224 | timeout as timeout_obj: object |
1225 | / |
1226 | |
1227 | Like sigwaitinfo(), but with a timeout. |
1228 | |
1229 | The timeout is specified in seconds, with floating point numbers allowed. |
1230 | [clinic start generated code]*/ |
1231 | |
1232 | static PyObject * |
1233 | signal_sigtimedwait_impl(PyObject *module, sigset_t sigset, |
1234 | PyObject *timeout_obj) |
1235 | /*[clinic end generated code: output=59c8971e8ae18a64 input=87fd39237cf0b7ba]*/ |
1236 | { |
1237 | struct timespec ts; |
1238 | siginfo_t si; |
1239 | int res; |
1240 | _PyTime_t timeout, deadline, monotonic; |
1241 | |
1242 | if (_PyTime_FromSecondsObject(&timeout, |
1243 | timeout_obj, _PyTime_ROUND_CEILING) < 0) |
1244 | return NULL; |
1245 | |
1246 | if (timeout < 0) { |
1247 | PyErr_SetString(PyExc_ValueError, "timeout must be non-negative" ); |
1248 | return NULL; |
1249 | } |
1250 | |
1251 | deadline = _PyTime_GetMonotonicClock() + timeout; |
1252 | |
1253 | do { |
1254 | if (_PyTime_AsTimespec(timeout, &ts) < 0) |
1255 | return NULL; |
1256 | |
1257 | Py_BEGIN_ALLOW_THREADS |
1258 | res = sigtimedwait(&sigset, &si, &ts); |
1259 | Py_END_ALLOW_THREADS |
1260 | |
1261 | if (res != -1) |
1262 | break; |
1263 | |
1264 | if (errno != EINTR) { |
1265 | if (errno == EAGAIN) |
1266 | Py_RETURN_NONE; |
1267 | else |
1268 | return PyErr_SetFromErrno(PyExc_OSError); |
1269 | } |
1270 | |
1271 | /* sigtimedwait() was interrupted by a signal (EINTR) */ |
1272 | if (PyErr_CheckSignals()) |
1273 | return NULL; |
1274 | |
1275 | monotonic = _PyTime_GetMonotonicClock(); |
1276 | timeout = deadline - monotonic; |
1277 | if (timeout < 0) |
1278 | break; |
1279 | } while (1); |
1280 | |
1281 | return fill_siginfo(&si); |
1282 | } |
1283 | |
1284 | #endif /* #ifdef HAVE_SIGTIMEDWAIT */ |
1285 | #endif /* #ifdef HAVE_SIGSET_T */ |
1286 | |
1287 | |
1288 | #if defined(HAVE_PTHREAD_KILL) |
1289 | |
1290 | /*[clinic input] |
1291 | signal.pthread_kill |
1292 | |
1293 | thread_id: unsigned_long(bitwise=True) |
1294 | signalnum: int |
1295 | / |
1296 | |
1297 | Send a signal to a thread. |
1298 | [clinic start generated code]*/ |
1299 | |
1300 | static PyObject * |
1301 | signal_pthread_kill_impl(PyObject *module, unsigned long thread_id, |
1302 | int signalnum) |
1303 | /*[clinic end generated code: output=7629919b791bc27f input=1d901f2c7bb544ff]*/ |
1304 | { |
1305 | int err; |
1306 | |
1307 | if (PySys_Audit("signal.pthread_kill" , "ki" , thread_id, signalnum) < 0) { |
1308 | return NULL; |
1309 | } |
1310 | |
1311 | err = pthread_kill((pthread_t)thread_id, signalnum); |
1312 | if (err != 0) { |
1313 | errno = err; |
1314 | PyErr_SetFromErrno(PyExc_OSError); |
1315 | return NULL; |
1316 | } |
1317 | |
1318 | /* the signal may have been send to the current thread */ |
1319 | if (PyErr_CheckSignals()) |
1320 | return NULL; |
1321 | |
1322 | Py_RETURN_NONE; |
1323 | } |
1324 | |
1325 | #endif /* #if defined(HAVE_PTHREAD_KILL) */ |
1326 | |
1327 | |
1328 | #if defined(__linux__) && defined(__NR_pidfd_send_signal) |
1329 | /*[clinic input] |
1330 | signal.pidfd_send_signal |
1331 | |
1332 | pidfd: int |
1333 | signalnum: int |
1334 | siginfo: object = None |
1335 | flags: int = 0 |
1336 | / |
1337 | |
1338 | Send a signal to a process referred to by a pid file descriptor. |
1339 | [clinic start generated code]*/ |
1340 | |
1341 | static PyObject * |
1342 | signal_pidfd_send_signal_impl(PyObject *module, int pidfd, int signalnum, |
1343 | PyObject *siginfo, int flags) |
1344 | /*[clinic end generated code: output=2d59f04a75d9cbdf input=2a6543a1f4ac2000]*/ |
1345 | |
1346 | { |
1347 | if (siginfo != Py_None) { |
1348 | PyErr_SetString(PyExc_TypeError, "siginfo must be None" ); |
1349 | return NULL; |
1350 | } |
1351 | if (syscall(__NR_pidfd_send_signal, pidfd, signalnum, NULL, flags) < 0) { |
1352 | PyErr_SetFromErrno(PyExc_OSError); |
1353 | return NULL; |
1354 | } |
1355 | Py_RETURN_NONE; |
1356 | } |
1357 | #endif |
1358 | |
1359 | |
1360 | |
1361 | /* List of functions defined in the module -- some of the methoddefs are |
1362 | defined to nothing if the corresponding C function is not available. */ |
1363 | static PyMethodDef signal_methods[] = { |
1364 | SIGNAL_DEFAULT_INT_HANDLER_METHODDEF |
1365 | SIGNAL_ALARM_METHODDEF |
1366 | SIGNAL_SETITIMER_METHODDEF |
1367 | SIGNAL_GETITIMER_METHODDEF |
1368 | SIGNAL_SIGNAL_METHODDEF |
1369 | SIGNAL_RAISE_SIGNAL_METHODDEF |
1370 | SIGNAL_STRSIGNAL_METHODDEF |
1371 | SIGNAL_GETSIGNAL_METHODDEF |
1372 | {"set_wakeup_fd" , (PyCFunction)(void(*)(void))signal_set_wakeup_fd, METH_VARARGS | METH_KEYWORDS, set_wakeup_fd_doc}, |
1373 | SIGNAL_SIGINTERRUPT_METHODDEF |
1374 | SIGNAL_PAUSE_METHODDEF |
1375 | SIGNAL_PIDFD_SEND_SIGNAL_METHODDEF |
1376 | SIGNAL_PTHREAD_KILL_METHODDEF |
1377 | SIGNAL_PTHREAD_SIGMASK_METHODDEF |
1378 | SIGNAL_SIGPENDING_METHODDEF |
1379 | SIGNAL_SIGWAIT_METHODDEF |
1380 | SIGNAL_SIGWAITINFO_METHODDEF |
1381 | SIGNAL_SIGTIMEDWAIT_METHODDEF |
1382 | #if defined(HAVE_SIGFILLSET) || defined(MS_WINDOWS) |
1383 | SIGNAL_VALID_SIGNALS_METHODDEF |
1384 | #endif |
1385 | {NULL, NULL} /* sentinel */ |
1386 | }; |
1387 | |
1388 | |
1389 | PyDoc_STRVAR(module_doc, |
1390 | "This module provides mechanisms to use signal handlers in Python.\n\ |
1391 | \n\ |
1392 | Functions:\n\ |
1393 | \n\ |
1394 | alarm() -- cause SIGALRM after a specified time [Unix only]\n\ |
1395 | setitimer() -- cause a signal (described below) after a specified\n\ |
1396 | float time and the timer may restart then [Unix only]\n\ |
1397 | getitimer() -- get current value of timer [Unix only]\n\ |
1398 | signal() -- set the action for a given signal\n\ |
1399 | getsignal() -- get the signal action for a given signal\n\ |
1400 | pause() -- wait until a signal arrives [Unix only]\n\ |
1401 | default_int_handler() -- default SIGINT handler\n\ |
1402 | \n\ |
1403 | signal constants:\n\ |
1404 | SIG_DFL -- used to refer to the system default handler\n\ |
1405 | SIG_IGN -- used to ignore the signal\n\ |
1406 | NSIG -- number of defined signals\n\ |
1407 | SIGINT, SIGTERM, etc. -- signal numbers\n\ |
1408 | \n\ |
1409 | itimer constants:\n\ |
1410 | ITIMER_REAL -- decrements in real time, and delivers SIGALRM upon\n\ |
1411 | expiration\n\ |
1412 | ITIMER_VIRTUAL -- decrements only when the process is executing,\n\ |
1413 | and delivers SIGVTALRM upon expiration\n\ |
1414 | ITIMER_PROF -- decrements both when the process is executing and\n\ |
1415 | when the system is executing on behalf of the process.\n\ |
1416 | Coupled with ITIMER_VIRTUAL, this timer is usually\n\ |
1417 | used to profile the time spent by the application\n\ |
1418 | in user and kernel space. SIGPROF is delivered upon\n\ |
1419 | expiration.\n\ |
1420 | \n\n\ |
1421 | *** IMPORTANT NOTICE ***\n\ |
1422 | A signal handler function is called with two arguments:\n\ |
1423 | the first is the signal number, the second is the interrupted stack frame." ); |
1424 | |
1425 | |
1426 | |
1427 | static int |
1428 | signal_add_constants(PyObject *module) |
1429 | { |
1430 | #define ADD_INT_MACRO(macro) \ |
1431 | if (PyModule_AddIntConstant(module, #macro, macro) < 0) { \ |
1432 | return -1; \ |
1433 | } |
1434 | |
1435 | ADD_INT_MACRO(NSIG); |
1436 | |
1437 | // SIG_xxx pthread_sigmask() constants |
1438 | #ifdef SIG_BLOCK |
1439 | ADD_INT_MACRO(SIG_BLOCK); |
1440 | #endif |
1441 | #ifdef SIG_UNBLOCK |
1442 | ADD_INT_MACRO(SIG_UNBLOCK); |
1443 | #endif |
1444 | #ifdef SIG_SETMASK |
1445 | ADD_INT_MACRO(SIG_SETMASK); |
1446 | #endif |
1447 | |
1448 | // SIGxxx signal number constants |
1449 | #ifdef SIGHUP |
1450 | ADD_INT_MACRO(SIGHUP); |
1451 | #endif |
1452 | #ifdef SIGINT |
1453 | ADD_INT_MACRO(SIGINT); |
1454 | #endif |
1455 | #ifdef SIGBREAK |
1456 | ADD_INT_MACRO(SIGBREAK); |
1457 | #endif |
1458 | #ifdef SIGQUIT |
1459 | ADD_INT_MACRO(SIGQUIT); |
1460 | #endif |
1461 | #ifdef SIGILL |
1462 | ADD_INT_MACRO(SIGILL); |
1463 | #endif |
1464 | #ifdef SIGTRAP |
1465 | ADD_INT_MACRO(SIGTRAP); |
1466 | #endif |
1467 | #ifdef SIGIOT |
1468 | ADD_INT_MACRO(SIGIOT); |
1469 | #endif |
1470 | #ifdef SIGABRT |
1471 | ADD_INT_MACRO(SIGABRT); |
1472 | #endif |
1473 | #ifdef SIGEMT |
1474 | ADD_INT_MACRO(SIGEMT); |
1475 | #endif |
1476 | #ifdef SIGFPE |
1477 | ADD_INT_MACRO(SIGFPE); |
1478 | #endif |
1479 | #ifdef SIGKILL |
1480 | ADD_INT_MACRO(SIGKILL); |
1481 | #endif |
1482 | #ifdef SIGBUS |
1483 | ADD_INT_MACRO(SIGBUS); |
1484 | #endif |
1485 | #ifdef SIGSEGV |
1486 | ADD_INT_MACRO(SIGSEGV); |
1487 | #endif |
1488 | #ifdef SIGSYS |
1489 | ADD_INT_MACRO(SIGSYS); |
1490 | #endif |
1491 | #ifdef SIGPIPE |
1492 | ADD_INT_MACRO(SIGPIPE); |
1493 | #endif |
1494 | #ifdef SIGALRM |
1495 | ADD_INT_MACRO(SIGALRM); |
1496 | #endif |
1497 | #ifdef SIGTERM |
1498 | ADD_INT_MACRO(SIGTERM); |
1499 | #endif |
1500 | #ifdef SIGUSR1 |
1501 | ADD_INT_MACRO(SIGUSR1); |
1502 | #endif |
1503 | #ifdef SIGUSR2 |
1504 | ADD_INT_MACRO(SIGUSR2); |
1505 | #endif |
1506 | #ifdef SIGCLD |
1507 | ADD_INT_MACRO(SIGCLD); |
1508 | #endif |
1509 | #ifdef SIGCHLD |
1510 | ADD_INT_MACRO(SIGCHLD); |
1511 | #endif |
1512 | #ifdef SIGPWR |
1513 | ADD_INT_MACRO(SIGPWR); |
1514 | #endif |
1515 | #ifdef SIGIO |
1516 | ADD_INT_MACRO(SIGIO); |
1517 | #endif |
1518 | #ifdef SIGURG |
1519 | ADD_INT_MACRO(SIGURG); |
1520 | #endif |
1521 | #ifdef SIGWINCH |
1522 | ADD_INT_MACRO(SIGWINCH); |
1523 | #endif |
1524 | #ifdef SIGPOLL |
1525 | ADD_INT_MACRO(SIGPOLL); |
1526 | #endif |
1527 | #ifdef SIGSTOP |
1528 | ADD_INT_MACRO(SIGSTOP); |
1529 | #endif |
1530 | #ifdef SIGTSTP |
1531 | ADD_INT_MACRO(SIGTSTP); |
1532 | #endif |
1533 | #ifdef SIGCONT |
1534 | ADD_INT_MACRO(SIGCONT); |
1535 | #endif |
1536 | #ifdef SIGTTIN |
1537 | ADD_INT_MACRO(SIGTTIN); |
1538 | #endif |
1539 | #ifdef SIGTTOU |
1540 | ADD_INT_MACRO(SIGTTOU); |
1541 | #endif |
1542 | #ifdef SIGVTALRM |
1543 | ADD_INT_MACRO(SIGVTALRM); |
1544 | #endif |
1545 | #ifdef SIGPROF |
1546 | ADD_INT_MACRO(SIGPROF); |
1547 | #endif |
1548 | #ifdef SIGXCPU |
1549 | ADD_INT_MACRO(SIGXCPU); |
1550 | #endif |
1551 | #ifdef SIGXFSZ |
1552 | ADD_INT_MACRO(SIGXFSZ); |
1553 | #endif |
1554 | #ifdef SIGRTMIN |
1555 | ADD_INT_MACRO(SIGRTMIN); |
1556 | #endif |
1557 | #ifdef SIGRTMAX |
1558 | ADD_INT_MACRO(SIGRTMAX); |
1559 | #endif |
1560 | #ifdef SIGINFO |
1561 | ADD_INT_MACRO(SIGINFO); |
1562 | #endif |
1563 | |
1564 | // ITIMER_xxx constants |
1565 | #ifdef ITIMER_REAL |
1566 | ADD_INT_MACRO(ITIMER_REAL); |
1567 | #endif |
1568 | #ifdef ITIMER_VIRTUAL |
1569 | ADD_INT_MACRO(ITIMER_VIRTUAL); |
1570 | #endif |
1571 | #ifdef ITIMER_PROF |
1572 | ADD_INT_MACRO(ITIMER_PROF); |
1573 | #endif |
1574 | |
1575 | // CTRL_xxx Windows signals |
1576 | #ifdef CTRL_C_EVENT |
1577 | ADD_INT_MACRO(CTRL_C_EVENT); |
1578 | #endif |
1579 | #ifdef CTRL_BREAK_EVENT |
1580 | ADD_INT_MACRO(CTRL_BREAK_EVENT); |
1581 | #endif |
1582 | |
1583 | return 0; |
1584 | |
1585 | #undef ADD_INT_MACRO |
1586 | } |
1587 | |
1588 | |
1589 | static int |
1590 | signal_get_set_handlers(signal_state_t *state, PyObject *mod_dict) |
1591 | { |
1592 | // Get signal handlers |
1593 | for (int signum = 1; signum < NSIG; signum++) { |
1594 | void (*c_handler)(int) = PyOS_getsig(signum); |
1595 | PyObject *func; |
1596 | if (c_handler == SIG_DFL) { |
1597 | func = state->default_handler; |
1598 | } |
1599 | else if (c_handler == SIG_IGN) { |
1600 | func = state->ignore_handler; |
1601 | } |
1602 | else { |
1603 | func = Py_None; // None of our business |
1604 | } |
1605 | // If signal_module_exec() is called more than one, we must |
1606 | // clear the strong reference to the previous function. |
1607 | PyObject* old_func = get_handler(signum); |
1608 | set_handler(signum, Py_NewRef(func)); |
1609 | Py_XDECREF(old_func); |
1610 | } |
1611 | |
1612 | // Install Python SIGINT handler which raises KeyboardInterrupt |
1613 | PyObject* sigint_func = get_handler(SIGINT); |
1614 | if (sigint_func == state->default_handler) { |
1615 | PyObject *int_handler = PyMapping_GetItemString(mod_dict, |
1616 | "default_int_handler" ); |
1617 | if (!int_handler) { |
1618 | return -1; |
1619 | } |
1620 | |
1621 | set_handler(SIGINT, int_handler); |
1622 | Py_DECREF(sigint_func); |
1623 | PyOS_setsig(SIGINT, signal_handler); |
1624 | } |
1625 | return 0; |
1626 | } |
1627 | |
1628 | |
1629 | static int |
1630 | signal_module_exec(PyObject *m) |
1631 | { |
1632 | assert(!PyErr_Occurred()); |
1633 | |
1634 | signal_state_t *state = &signal_global_state; |
1635 | _signal_module_state *modstate = get_signal_state(m); |
1636 | |
1637 | modstate->default_handler = state->default_handler; // borrowed ref |
1638 | modstate->ignore_handler = state->ignore_handler; // borrowed ref |
1639 | |
1640 | #ifdef PYHAVE_ITIMER_ERROR |
1641 | modstate->itimer_error = PyErr_NewException("signal.itimer_error" , |
1642 | PyExc_OSError, NULL); |
1643 | if (modstate->itimer_error == NULL) { |
1644 | return -1; |
1645 | } |
1646 | #endif |
1647 | |
1648 | if (signal_add_constants(m) < 0) { |
1649 | return -1; |
1650 | } |
1651 | |
1652 | /* Add some symbolic constants to the module */ |
1653 | PyObject *d = PyModule_GetDict(m); |
1654 | if (PyDict_SetItemString(d, "SIG_DFL" , state->default_handler) < 0) { |
1655 | return -1; |
1656 | } |
1657 | if (PyDict_SetItemString(d, "SIG_IGN" , state->ignore_handler) < 0) { |
1658 | return -1; |
1659 | } |
1660 | #ifdef PYHAVE_ITIMER_ERROR |
1661 | if (PyDict_SetItemString(d, "ItimerError" , modstate->itimer_error) < 0) { |
1662 | return -1; |
1663 | } |
1664 | #endif |
1665 | #if defined(HAVE_SIGWAITINFO) || defined(HAVE_SIGTIMEDWAIT) |
1666 | if (PyModule_AddType(m, &SiginfoType) < 0) { |
1667 | return -1; |
1668 | } |
1669 | #endif |
1670 | |
1671 | PyThreadState *tstate = _PyThreadState_GET(); |
1672 | if (_Py_IsMainInterpreter(tstate->interp)) { |
1673 | if (signal_get_set_handlers(state, d) < 0) { |
1674 | return -1; |
1675 | } |
1676 | } |
1677 | |
1678 | assert(!PyErr_Occurred()); |
1679 | return 0; |
1680 | } |
1681 | |
1682 | |
1683 | #ifdef PYHAVE_ITIMER_ERROR |
1684 | static int |
1685 | _signal_module_traverse(PyObject *module, visitproc visit, void *arg) |
1686 | { |
1687 | _signal_module_state *modstate = get_signal_state(module); |
1688 | Py_VISIT(modstate->itimer_error); |
1689 | return 0; |
1690 | } |
1691 | |
1692 | static int |
1693 | _signal_module_clear(PyObject *module) |
1694 | { |
1695 | _signal_module_state *modstate = get_signal_state(module); |
1696 | Py_CLEAR(modstate->itimer_error); |
1697 | return 0; |
1698 | } |
1699 | |
1700 | static void |
1701 | _signal_module_free(void *module) |
1702 | { |
1703 | _signal_module_clear((PyObject *)module); |
1704 | } |
1705 | #endif // PYHAVE_ITIMER_ERROR |
1706 | |
1707 | |
1708 | static PyModuleDef_Slot signal_slots[] = { |
1709 | {Py_mod_exec, signal_module_exec}, |
1710 | {0, NULL} |
1711 | }; |
1712 | |
1713 | static struct PyModuleDef signal_module = { |
1714 | PyModuleDef_HEAD_INIT, |
1715 | "_signal" , |
1716 | .m_doc = module_doc, |
1717 | .m_size = sizeof(_signal_module_state), |
1718 | .m_methods = signal_methods, |
1719 | .m_slots = signal_slots, |
1720 | #ifdef PYHAVE_ITIMER_ERROR |
1721 | .m_traverse = _signal_module_traverse, |
1722 | .m_clear = _signal_module_clear, |
1723 | .m_free = _signal_module_free, |
1724 | #endif |
1725 | }; |
1726 | |
1727 | |
1728 | PyMODINIT_FUNC |
1729 | PyInit__signal(void) |
1730 | { |
1731 | return PyModuleDef_Init(&signal_module); |
1732 | } |
1733 | |
1734 | |
1735 | void |
1736 | _PySignal_Fini(void) |
1737 | { |
1738 | signal_state_t *state = &signal_global_state; |
1739 | |
1740 | // Restore default signals and clear handlers |
1741 | for (int signum = 1; signum < NSIG; signum++) { |
1742 | PyObject *func = get_handler(signum); |
1743 | _Py_atomic_store_relaxed(&Handlers[signum].tripped, 0); |
1744 | set_handler(signum, NULL); |
1745 | if (func != NULL |
1746 | && func != Py_None |
1747 | && !compare_handler(func, state->default_handler) |
1748 | && !compare_handler(func, state->ignore_handler)) |
1749 | { |
1750 | PyOS_setsig(signum, SIG_DFL); |
1751 | } |
1752 | Py_XDECREF(func); |
1753 | } |
1754 | |
1755 | #ifdef MS_WINDOWS |
1756 | if (state->sigint_event != NULL) { |
1757 | CloseHandle(state->sigint_event); |
1758 | state->sigint_event = NULL; |
1759 | } |
1760 | #endif |
1761 | |
1762 | Py_CLEAR(state->default_handler); |
1763 | Py_CLEAR(state->ignore_handler); |
1764 | } |
1765 | |
1766 | |
1767 | /* Declared in pyerrors.h */ |
1768 | int |
1769 | PyErr_CheckSignals(void) |
1770 | { |
1771 | PyThreadState *tstate = _PyThreadState_GET(); |
1772 | if (!_Py_ThreadCanHandleSignals(tstate->interp)) { |
1773 | return 0; |
1774 | } |
1775 | |
1776 | return _PyErr_CheckSignalsTstate(tstate); |
1777 | } |
1778 | |
1779 | |
1780 | /* Declared in cpython/pyerrors.h */ |
1781 | int |
1782 | _PyErr_CheckSignalsTstate(PyThreadState *tstate) |
1783 | { |
1784 | if (!_Py_atomic_load(&is_tripped)) { |
1785 | return 0; |
1786 | } |
1787 | |
1788 | /* |
1789 | * The is_tripped variable is meant to speed up the calls to |
1790 | * PyErr_CheckSignals (both directly or via pending calls) when no |
1791 | * signal has arrived. This variable is set to 1 when a signal arrives |
1792 | * and it is set to 0 here, when we know some signals arrived. This way |
1793 | * we can run the registered handlers with no signals blocked. |
1794 | * |
1795 | * NOTE: with this approach we can have a situation where is_tripped is |
1796 | * 1 but we have no more signals to handle (Handlers[i].tripped |
1797 | * is 0 for every signal i). This won't do us any harm (except |
1798 | * we're gonna spent some cycles for nothing). This happens when |
1799 | * we receive a signal i after we zero is_tripped and before we |
1800 | * check Handlers[i].tripped. |
1801 | */ |
1802 | _Py_atomic_store(&is_tripped, 0); |
1803 | |
1804 | PyObject *frame = (PyObject *)tstate->frame; |
1805 | if (!frame) { |
1806 | frame = Py_None; |
1807 | } |
1808 | |
1809 | signal_state_t *state = &signal_global_state; |
1810 | for (int i = 1; i < NSIG; i++) { |
1811 | if (!_Py_atomic_load_relaxed(&Handlers[i].tripped)) { |
1812 | continue; |
1813 | } |
1814 | _Py_atomic_store_relaxed(&Handlers[i].tripped, 0); |
1815 | |
1816 | /* Signal handlers can be modified while a signal is received, |
1817 | * and therefore the fact that trip_signal() or PyErr_SetInterrupt() |
1818 | * was called doesn't guarantee that there is still a Python |
1819 | * signal handler for it by the time PyErr_CheckSignals() is called |
1820 | * (see bpo-43406). |
1821 | */ |
1822 | PyObject *func = get_handler(i); |
1823 | if (func == NULL || func == Py_None || |
1824 | compare_handler(func, state->ignore_handler) || |
1825 | compare_handler(func, state->default_handler)) { |
1826 | /* No Python signal handler due to aforementioned race condition. |
1827 | * We can't call raise() as it would break the assumption |
1828 | * that PyErr_SetInterrupt() only *simulates* an incoming |
1829 | * signal (i.e. it will never kill the process). |
1830 | * We also don't want to interrupt user code with a cryptic |
1831 | * asynchronous exception, so instead just write out an |
1832 | * unraisable error. |
1833 | */ |
1834 | PyErr_Format(PyExc_OSError, |
1835 | "Signal %i ignored due to race condition" , |
1836 | i); |
1837 | PyErr_WriteUnraisable(Py_None); |
1838 | continue; |
1839 | } |
1840 | |
1841 | PyObject *arglist = Py_BuildValue("(iO)" , i, frame); |
1842 | PyObject *result; |
1843 | if (arglist) { |
1844 | result = _PyObject_Call(tstate, func, arglist, NULL); |
1845 | Py_DECREF(arglist); |
1846 | } |
1847 | else { |
1848 | result = NULL; |
1849 | } |
1850 | if (!result) { |
1851 | /* On error, re-schedule a call to _PyErr_CheckSignalsTstate() */ |
1852 | _Py_atomic_store(&is_tripped, 1); |
1853 | return -1; |
1854 | } |
1855 | |
1856 | Py_DECREF(result); |
1857 | } |
1858 | |
1859 | return 0; |
1860 | } |
1861 | |
1862 | |
1863 | |
1864 | int |
1865 | _PyErr_CheckSignals(void) |
1866 | { |
1867 | PyThreadState *tstate = _PyThreadState_GET(); |
1868 | return _PyErr_CheckSignalsTstate(tstate); |
1869 | } |
1870 | |
1871 | |
1872 | /* Simulate the effect of a signal arriving. The next time PyErr_CheckSignals |
1873 | is called, the corresponding Python signal handler will be raised. |
1874 | |
1875 | Missing signal handler for the given signal number is silently ignored. */ |
1876 | int |
1877 | PyErr_SetInterruptEx(int signum) |
1878 | { |
1879 | if (signum < 1 || signum >= NSIG) { |
1880 | return -1; |
1881 | } |
1882 | |
1883 | signal_state_t *state = &signal_global_state; |
1884 | PyObject *func = get_handler(signum); |
1885 | if (!compare_handler(func, state->ignore_handler) |
1886 | && !compare_handler(func, state->default_handler)) { |
1887 | trip_signal(signum); |
1888 | } |
1889 | return 0; |
1890 | } |
1891 | |
1892 | void |
1893 | PyErr_SetInterrupt(void) |
1894 | { |
1895 | (void) PyErr_SetInterruptEx(SIGINT); |
1896 | } |
1897 | |
1898 | static int |
1899 | signal_install_handlers(void) |
1900 | { |
1901 | #ifdef SIGPIPE |
1902 | PyOS_setsig(SIGPIPE, SIG_IGN); |
1903 | #endif |
1904 | #ifdef SIGXFZ |
1905 | PyOS_setsig(SIGXFZ, SIG_IGN); |
1906 | #endif |
1907 | #ifdef SIGXFSZ |
1908 | PyOS_setsig(SIGXFSZ, SIG_IGN); |
1909 | #endif |
1910 | |
1911 | // Import _signal to install the Python SIGINT handler |
1912 | PyObject *module = PyImport_ImportModule("_signal" ); |
1913 | if (!module) { |
1914 | return -1; |
1915 | } |
1916 | Py_DECREF(module); |
1917 | |
1918 | return 0; |
1919 | } |
1920 | |
1921 | |
1922 | /* Restore signals that the interpreter has called SIG_IGN on to SIG_DFL. |
1923 | * |
1924 | * All of the code in this function must only use async-signal-safe functions, |
1925 | * listed at `man 7 signal` or |
1926 | * http://www.opengroup.org/onlinepubs/009695399/functions/xsh_chap02_04.html. |
1927 | * |
1928 | * If this function is updated, update also _posix_spawn() of subprocess.py. |
1929 | */ |
1930 | void |
1931 | _Py_RestoreSignals(void) |
1932 | { |
1933 | #ifdef SIGPIPE |
1934 | PyOS_setsig(SIGPIPE, SIG_DFL); |
1935 | #endif |
1936 | #ifdef SIGXFZ |
1937 | PyOS_setsig(SIGXFZ, SIG_DFL); |
1938 | #endif |
1939 | #ifdef SIGXFSZ |
1940 | PyOS_setsig(SIGXFSZ, SIG_DFL); |
1941 | #endif |
1942 | } |
1943 | |
1944 | |
1945 | int |
1946 | _PySignal_Init(int install_signal_handlers) |
1947 | { |
1948 | signal_state_t *state = &signal_global_state; |
1949 | |
1950 | state->default_handler = PyLong_FromVoidPtr((void *)SIG_DFL); |
1951 | if (state->default_handler == NULL) { |
1952 | return -1; |
1953 | } |
1954 | |
1955 | state->ignore_handler = PyLong_FromVoidPtr((void *)SIG_IGN); |
1956 | if (state->ignore_handler == NULL) { |
1957 | return -1; |
1958 | } |
1959 | |
1960 | #ifdef MS_WINDOWS |
1961 | /* Create manual-reset event, initially unset */ |
1962 | state->sigint_event = CreateEvent(NULL, TRUE, FALSE, FALSE); |
1963 | if (state->sigint_event == NULL) { |
1964 | PyErr_SetFromWindowsErr(0); |
1965 | return -1; |
1966 | } |
1967 | #endif |
1968 | |
1969 | #if defined(HAVE_SIGWAITINFO) || defined(HAVE_SIGTIMEDWAIT) |
1970 | if (SiginfoType.tp_name == NULL) { |
1971 | if (PyStructSequence_InitType2(&SiginfoType, &struct_siginfo_desc) < 0) { |
1972 | return -1; |
1973 | } |
1974 | } |
1975 | #endif |
1976 | |
1977 | for (int signum = 1; signum < NSIG; signum++) { |
1978 | _Py_atomic_store_relaxed(&Handlers[signum].tripped, 0); |
1979 | } |
1980 | |
1981 | if (install_signal_handlers) { |
1982 | if (signal_install_handlers() < 0) { |
1983 | return -1; |
1984 | } |
1985 | } |
1986 | |
1987 | return 0; |
1988 | } |
1989 | |
1990 | |
1991 | // The caller doesn't have to hold the GIL |
1992 | int |
1993 | _PyOS_InterruptOccurred(PyThreadState *tstate) |
1994 | { |
1995 | _Py_EnsureTstateNotNULL(tstate); |
1996 | if (!_Py_ThreadCanHandleSignals(tstate->interp)) { |
1997 | return 0; |
1998 | } |
1999 | |
2000 | if (!_Py_atomic_load_relaxed(&Handlers[SIGINT].tripped)) { |
2001 | return 0; |
2002 | } |
2003 | |
2004 | _Py_atomic_store_relaxed(&Handlers[SIGINT].tripped, 0); |
2005 | return 1; |
2006 | } |
2007 | |
2008 | |
2009 | // The caller must to hold the GIL |
2010 | int |
2011 | PyOS_InterruptOccurred(void) |
2012 | { |
2013 | PyThreadState *tstate = _PyThreadState_GET(); |
2014 | return _PyOS_InterruptOccurred(tstate); |
2015 | } |
2016 | |
2017 | |
2018 | #ifdef HAVE_FORK |
2019 | static void |
2020 | _clear_pending_signals(void) |
2021 | { |
2022 | if (!_Py_atomic_load(&is_tripped)) { |
2023 | return; |
2024 | } |
2025 | |
2026 | _Py_atomic_store(&is_tripped, 0); |
2027 | for (int i = 1; i < NSIG; ++i) { |
2028 | _Py_atomic_store_relaxed(&Handlers[i].tripped, 0); |
2029 | } |
2030 | } |
2031 | |
2032 | void |
2033 | _PySignal_AfterFork(void) |
2034 | { |
2035 | /* Clear the signal flags after forking so that they aren't handled |
2036 | * in both processes if they came in just before the fork() but before |
2037 | * the interpreter had an opportunity to call the handlers. issue9535. */ |
2038 | _clear_pending_signals(); |
2039 | } |
2040 | #endif /* HAVE_FORK */ |
2041 | |
2042 | |
2043 | int |
2044 | _PyOS_IsMainThread(void) |
2045 | { |
2046 | PyInterpreterState *interp = _PyInterpreterState_GET(); |
2047 | return _Py_ThreadCanHandleSignals(interp); |
2048 | } |
2049 | |
2050 | #ifdef MS_WINDOWS |
2051 | /* Returns a manual-reset event which gets tripped whenever |
2052 | SIGINT is received. |
2053 | |
2054 | Python.h does not include windows.h so we do cannot use HANDLE |
2055 | as the return type of this function. We use void* instead. */ |
2056 | void *_PyOS_SigintEvent(void) |
2057 | { |
2058 | signal_state_t *state = &signal_global_state; |
2059 | return state->sigint_event; |
2060 | } |
2061 | #endif |
2062 | |