from __future__ import print_function import signal as cpy_signal import sys import os import errno from pypy.interpreter.error import ( OperationError, exception_from_saved_errno, oefmt, wrap_oserror) from pypy.interpreter.executioncontext import (AsyncAction, AbstractActionFlag, PeriodicAsyncAction) from pypy.interpreter.gateway import unwrap_spec from rpython.rlib import jit, rgc, rposix, rposix_stat, rthread from rpython.rlib.objectmodel import we_are_translated from rpython.rlib.rarithmetic import intmask, widen from rpython.rlib.rsignal import * from rpython.rtyper.lltypesystem import lltype, rffi WIN32 = sys.platform == 'win32' class SignalActionFlag(AbstractActionFlag): # This class uses the C-level pypysig_counter variable as the tick # counter. The C-level signal handler will reset it to -1 whenever # a signal is received. This causes CheckSignalAction.perform() to # be called. def get_ticker(self): p = pypysig_getaddr_occurred() return p.c_value def reset_ticker(self, value): p = pypysig_getaddr_occurred() p.c_value = value def rearm_ticker(self): p = pypysig_getaddr_occurred() p.c_value = -1 def decrement_ticker(self, by): p = pypysig_getaddr_occurred() value = p.c_value if self.has_bytecode_counter: # this 'if' is constant-folded if jit.isconstant(by) and by == 0: pass # normally constant-folded too else: value -= by p.c_value = value return value class CheckSignalAction(PeriodicAsyncAction): """An action that is automatically invoked when a signal is received.""" # Note that this is a PeriodicAsyncAction: it means more precisely # that it is called whenever the C-level ticker becomes < 0. # Without threads, it is only ever set to -1 when we receive a # signal. With threads, it also decrements steadily (but slowly). def __init__(self, space): "NOT_RPYTHON" AsyncAction.__init__(self, space) self.pending_signal = -1 self.fire_in_another_thread = False @rgc.no_collect def _after_thread_switch(): # if threadlocals is the fake ThreadLocals from miscutils, we # cannot ever end up here, it's only called after a thread switch ec = self.space.threadlocals.get_ec() if ec is not None and ec.w_async_exception_type: self.space.actionflag.rearm_ticker() # ensure perform is called return if self.fire_in_another_thread: if self.space.threadlocals.signals_enabled(): self.fire_in_another_thread = False self.space.actionflag.rearm_ticker() # this occurs when we just switched to the main thread # and there is a signal pending: we force the ticker to # -1, which should ensure perform() is called quickly. self._after_thread_switch = _after_thread_switch # ^^^ so that 'self._after_thread_switch' can be annotated as a # constant def startup(self, space): # this is translated if space.config.objspace.usemodules.thread: from rpython.rlib import rgil rgil.invoke_after_thread_switch(self._after_thread_switch) def perform(self, executioncontext, frame): w_exc = executioncontext.w_async_exception_type if w_exc is not None: executioncontext.w_async_exception_type = None raise oefmt(w_exc, "asynchronous exception triggered from another thread") self._poll_for_signals() @jit.dont_look_inside def _poll_for_signals(self): # Poll for the next signal, if any n = self.pending_signal p = pypysig_getaddr_occurred_fullstruct() if p.c_debugger_pending_call: path = rffi.charp2str(p.c_debugger_script_path) p.c_debugger_pending_call = 0 run_debugger(self.space, path) return if n < 0: n = pypysig_poll() while n >= 0: if self.space.threadlocals.signals_enabled(): # If we are in the main thread, report the signal now, # and poll more self.pending_signal = -1 report_signal(self.space, n) n = self.pending_signal if n < 0: n = pypysig_poll() else: # Otherwise, arrange for perform() to be called again # after we switch to the main thread. self.pending_signal = n self.fire_in_another_thread = True break def set_interrupt(self, signum=cpy_signal.SIGINT): "Simulates the effect of a signal arriving, defaults to SIGINT" if not (1 <= signum < NSIG): return if not we_are_translated(): self.pending_signal = signum # ^^^ may override another signal, but it's just for testing self.fire_in_another_thread = True else: pypysig_pushback(signum) # ____________________________________________________________ class Handlers: def __init__(self, space): self.handlers_w = {} for signum in range(1, NSIG): if WIN32 and signum not in signal_values: self.handlers_w[signum] = space.w_None else: self.handlers_w[signum] = space.newint(SIG_DFL) def _get_handlers(space): return space.fromcache(Handlers).handlers_w def report_signal(space, n): handlers_w = _get_handlers(space) try: w_handler = handlers_w[n] except KeyError: return # no handler, ignore signal if not space.is_true(space.callable(w_handler)): return # w_handler is SIG_IGN or SIG_DFL? # re-install signal handler, for OSes that clear it pypysig_reinstall(n) # invoke the app-level handler ec = space.getexecutioncontext() w_frame = ec.gettopframe_nohidden() space.call_function(w_handler, space.newint(n), w_frame) def run_debugger(space, path): from pypy.interpreter.streamutil import wrap_streamerror from pypy.interpreter.eval import Code from rpython.rlib import streamio w_pypymod = space.getbuiltinmodule('__pypy__') if space.is_true(space.getattr(w_pypymod, space.newtext('_pypy_disable_remote_debugger'))): return try: w_file = space.call_method(space.newbytes(path), 'decode', space.newtext('utf-8')) space.audit('remote_exec', [w_file]) msg = "Executing remote debugger script " w_msg = space.add(space.newtext(msg), w_file) w_msg = space.add(w_msg, space.newtext('\n')) space.call_method(space.getattr(space.sys, space.newtext('stdout')), 'write', w_msg) try: stream = streamio.open_file_as_stream(path, 'r') source = stream.readall() except streamio.StreamErrors as e: raise wrap_streamerror(space, e) ec = space.getexecutioncontext() pycode = ec.compiler.compile(source, path, 'exec', 0) w_globals = space.newdict() pycode.exec_code(space, w_globals, w_globals) except OperationError as e: e.write_unraisable(space, "in remote debugger invocation") @unwrap_spec(signum=int) def getsignal(space, signum): """ getsignal(sig) -> action 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 """ check_signum_in_range(space, signum) handlers_w = _get_handlers(space) return handlers_w[signum] def default_int_handler(space, args_w): """ default_int_handler(...) The default handler for SIGINT installed by Python. It raises KeyboardInterrupt. """ # issue #2780: accept and ignore any non-keyword arguments raise OperationError(space.w_KeyboardInterrupt, space.w_None) @jit.dont_look_inside @unwrap_spec(timeout=int) def alarm(space, timeout): """alarm(seconds) Arrange for SIGALRM to arrive after the given number of seconds. """ return space.newint(c_alarm(timeout)) @jit.dont_look_inside def pause(space): """pause() Wait until a signal arrives. """ c_pause() return space.w_None def check_signum_in_range(space, signum): if 1 <= signum < NSIG: return raise oefmt(space.w_ValueError, "signal number out of range") @jit.dont_look_inside @unwrap_spec(signum=int) def signal(space, signum, w_handler): """ signal(sig, action) -> action 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. """ if WIN32 and signum not in signal_values: raise oefmt(space.w_ValueError, "invalid signal value") if not space.threadlocals.signals_enabled(): raise oefmt(space.w_ValueError, "signal only works in main thread or with " "__pypy__.thread.enable_signals()") check_signum_in_range(space, signum) if space.eq_w(w_handler, space.newint(SIG_DFL)): pypysig_default(signum) elif space.eq_w(w_handler, space.newint(SIG_IGN)): pypysig_ignore(signum) else: if not space.is_true(space.callable(w_handler)): raise oefmt(space.w_TypeError, "'handler' must be a callable or SIG_DFL or SIG_IGN") pypysig_setflag(signum) handlers_w = _get_handlers(space) old_handler = handlers_w[signum] handlers_w[signum] = w_handler return old_handler @jit.dont_look_inside @unwrap_spec(fd="c_int", warn_on_full_buffer=bool) def set_wakeup_fd(space, fd, __kwonly__, warn_on_full_buffer=True): """Sets the fd to be written to (with the signal number) when a signal comes in. Returns the old fd. A library can use this to wakeup select or poll. The previous fd is returned. The fd must be non-blocking. """ if not space.threadlocals.signals_enabled(): raise oefmt(space.w_ValueError, "set_wakeup_fd only works in main thread or with " "__pypy__.thread.enable_signals()") send_flags = 0 if fd != -1: if WIN32: from rpython.rlib._rsocket_rffi import SOL_SOCKET, SO_TYPE from rpython.rlib.rsocket import getsockopt_int, SocketError # it could be a socket fd or a file fd try: type = getsockopt_int(fd, SOL_SOCKET, SO_TYPE) is_socket = True except SocketError as e: is_socket = False if is_socket: send_flags |= PYPYSIG_USE_SEND else: try: os.fstat(fd) except OSError as e: if e.errno == errno.EBADF: raise oefmt(space.w_ValueError, "invalid fd") else: try: os.fstat(fd) flags = rposix.get_status_flags(fd) except OSError as e: if e.errno == errno.EBADF: raise oefmt(space.w_ValueError, "invalid fd") raise wrap_oserror(space, e, eintr_retry=False) if flags & rposix.O_NONBLOCK == 0: raise oefmt(space.w_ValueError, "the fd %d must be in non-blocking mode", fd) if not warn_on_full_buffer: send_flags |= PYPYSIG_NO_WARN_FULL old_fd = pypysig_set_wakeup_fd(fd, send_flags) return space.newint(intmask(old_fd)) @jit.dont_look_inside @unwrap_spec(signum=int, flag=int) def siginterrupt(space, signum, flag): """siginterrupt(sig, flag) -> None 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. """ check_signum_in_range(space, signum) if rffi.cast(lltype.Signed, c_siginterrupt(signum, flag)) < 0: raise exception_from_saved_errno(space, space.w_OSError) #__________________________________________________________ def timeval_from_double(d, timeval): c_tv_sec = int(d) c_tv_usec = int((d - int(d)) * 1000000) # Don't disable the timer if the computation above rounds down to zero. if d > 0.0 and c_tv_sec == 0 and c_tv_usec == 0: c_tv_usec = 1 rffi.setintfield(timeval, 'c_tv_sec', c_tv_sec) rffi.setintfield(timeval, 'c_tv_usec', c_tv_usec) def double_from_timeval(tv): return rffi.getintfield(tv, 'c_tv_sec') + ( rffi.getintfield(tv, 'c_tv_usec') / 1000000.0) def itimer_retval(space, val): w_value = space.newfloat(double_from_timeval(val.c_it_value)) w_interval = space.newfloat(double_from_timeval(val.c_it_interval)) return space.newtuple2(w_value, w_interval) class Cache: def __init__(self, space): self.w_itimererror = space.new_exception_class("signal.ItimerError", space.w_IOError) def get_itimer_error(space): return space.fromcache(Cache).w_itimererror @jit.dont_look_inside @unwrap_spec(which=int, first=float, interval=float) def setitimer(space, which, first, interval=0): """setitimer(which, seconds[, interval]) Sets given itimer (one of ITIMER_REAL, ITIMER_VIRTUAL or ITIMER_PROF) to 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). """ with lltype.scoped_alloc(itimervalP.TO, 1) as new: timeval_from_double(first, new[0].c_it_value) timeval_from_double(interval, new[0].c_it_interval) with lltype.scoped_alloc(itimervalP.TO, 1) as old: ret = c_setitimer(which, new, old) if ret != 0: raise exception_from_saved_errno(space, get_itimer_error(space)) return itimer_retval(space, old[0]) @jit.dont_look_inside @unwrap_spec(which=int) def getitimer(space, which): """getitimer(which) Returns current value of given itimer. """ with lltype.scoped_alloc(itimervalP.TO, 1) as old: c_getitimer(which, old) return itimer_retval(space, old[0]) @unwrap_spec(tid=int, signum=int) def pthread_kill(space, tid, signum): "Send a signal to a thread." ret = rthread.c_pthread_kill(tid, signum) if widen(ret) < 0: raise exception_from_saved_errno(space, space.w_OSError) # the signal may have been send to the current thread space.getexecutioncontext().checksignals() class SignalMask(object): def __init__(self, space, w_signals): self.space = space self.w_signals = w_signals def __enter__(self): space = self.space self.mask = lltype.malloc(c_sigset_t.TO, flavor='raw') c_sigemptyset(self.mask) for w_signum in space.unpackiterable(self.w_signals): signum = space.int_w(w_signum) check_signum_in_range(space, signum) # bpo-33329: ignore c_sigaddset() return value as it can fail # for some reserved signals, but we want the `range(1, NSIG)` # idiom to allow selecting all valid signals. c_sigaddset(self.mask, signum) return self.mask def __exit__(self, *args): lltype.free(self.mask, flavor='raw') def _sigset_to_signals(space, mask): signals_w = [] for sig in range(1, NSIG): if c_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. signals_w.append(space.newint(sig)) return space.call_function(space.w_set, space.newtuple(signals_w)) def sigwait(space, w_signals): """Suspend execution of the calling thread until the delivery of one of the signals specified in the signal set signals. """ with SignalMask(space, w_signals) as sigset: with lltype.scoped_alloc(rffi.INT_realP.TO, 1) as signum_ptr: ret = widen(c_sigwait(sigset, signum_ptr)) if ret != 0: raise exception_from_saved_errno(space, space.w_OSError) signum = signum_ptr[0] return space.newint(signum) def sigpending(space): """Examine pending signals. Returns a set of signal numbers that are pending for delivery to the calling thread. """ with lltype.scoped_alloc(c_sigset_t.TO) as mask: ret = c_sigpending(mask) if ret != 0: raise exception_from_saved_errno(space, space.w_OSError) return _sigset_to_signals(space, mask) @unwrap_spec(how=int) def pthread_sigmask(space, how, w_signals): 'Fetch and/or change the signal mask of the calling thread.' with SignalMask(space, w_signals) as sigset: with lltype.scoped_alloc(c_sigset_t.TO) as previous: ret = c_pthread_sigmask(how, sigset, previous) if ret != 0: raise exception_from_saved_errno(space, space.w_OSError) # if signals was unblocked, signal handlers have been called space.getexecutioncontext().checksignals() return _sigset_to_signals(space, previous) def valid_signals(space): '''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`.''' if WIN32: # follow cpython signals_w = [space.newint(SIGABRT), space.newint(SIGBREAK), space.newint(SIGFPE), space.newint(SIGILL), space.newint(SIGINT), space.newint(SIGSEGV), space.newint(SIGTERM), ] return space.call_function(space.w_set, space.newtuple(signals_w)) else: mask = lltype.malloc(c_sigset_t.TO, flavor='raw') try: ret = c_sigemptyset(mask) if ret != 0: raise exception_from_saved_errno(space, space.w_OSError) ret = c_sigfillset(mask) if ret != 0: raise exception_from_saved_errno(space, space.w_OSError) return _sigset_to_signals(space, mask) finally: lltype.free(mask, flavor='raw') @unwrap_spec(signalnum=int) def raise_signal(space, signalnum): 'Send a signal to the executing process.' with rposix.SuppressIPH(): err = c_raise(signalnum) if err != 0: raise exception_from_saved_errno(space, space.w_OSError) @unwrap_spec(signalnum=int) def strsignal(space, signalnum): '''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.''' from rpython.rlib import rsignal if signalnum < 1 or signalnum > NSIG: raise oefmt(space.w_ValueError, 'signal number out of range') res = rsignal.strsignal(signalnum) if res is None: return space.w_None return space.newtext(res)