# Copyright (C) 2006, 2007, 2009 Canonical Ltd # # This program is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation; either version 2 of the License, or # (at your option) any later version. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program; if not, write to the Free Software # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA """Blackbox tests for debugger breakin""" try: import ctypes have_ctypes = True except ImportError: have_ctypes = False import errno import os import signal import subprocess import sys import time from bzrlib import ( breakin, errors, tests, ) class TestBreakin(tests.TestCase): # FIXME: If something is broken, these tests may just hang indefinitely in # wait() waiting for the child to exit when it's not going to. def setUp(self): super(TestBreakin, self).setUp() self.requireFeature(tests.BreakinFeature) if sys.platform == 'win32': self._send_signal = self._send_signal_win32 else: self._send_signal = self._send_signal_via_kill def _send_signal_via_kill(self, pid, sig_type): if sig_type == 'break': sig_num = signal.SIGQUIT elif sig_type == 'kill': sig_num = signal.SIGKILL else: raise ValueError("unknown signal type: %s" % (sig_type,)) try: os.kill(pid, sig_num) except OSError, e: if e.errno != errno.ESRCH: raise def _send_signal_win32(self, pid, sig_type): """Send a 'signal' on Windows. Windows doesn't really have signals in the same way. All it really supports is: 1) Sending SIGINT to the *current* process group (so self, and all children of self) 2) Sending SIGBREAK to a process that shares the current console, which can be in its own process group. So we have start_bzr_subprocess create a new process group for the spawned process (via a flag to Popen), and then we map SIGQUIT to GenerateConsoleCtrlEvent(CTRL_BREAK_EVENT) SIGKILL to TerminateProcess """ if sig_type == 'break': CTRL_BREAK_EVENT = 1 # CTRL_C_EVENT = 0 ret = ctypes.windll.kernel32.GenerateConsoleCtrlEvent( CTRL_BREAK_EVENT, pid) if ret == 0: #error err = ctypes.FormatError() raise RuntimeError('failed to send CTRL_BREAK: %s' % (err,)) elif sig_type == 'kill': # Does the exit code matter? For now we are just setting it to # something other than 0 exit_code = breakin.determine_signal() ctypes.windll.kernel32.TerminateProcess(pid, exit_code) def _popen(self, *args, **kwargs): if sys.platform == 'win32': CREATE_NEW_PROCESS_GROUP = 512 # This allows us to send a signal to the child, *without* also # sending it to ourselves kwargs['creationflags'] = CREATE_NEW_PROCESS_GROUP return super(TestBreakin, self)._popen(*args, **kwargs) def _dont_SIGQUIT_on_darwin(self): if sys.platform == 'darwin': # At least on Leopard and with python 2.6, this test will raise a # popup window asking if the python failure should be reported to # Apple... That's not the point of the test :) Marking the test as # not applicable Until we find a way to disable that intrusive # behavior... --vila20080611 raise tests.TestNotApplicable( '%s raises a popup on OSX' % self.id()) def _wait_for_process(self, pid, sig=None, count=100): # We don't know quite how long waiting for the process 'pid' will take, # but if it's more than 10s then it's probably not going to work. for i in range(count): if sig is not None: self._send_signal(pid, sig) # Use WNOHANG to ensure we don't get blocked, doing so, we may # leave the process continue after *we* die... # Win32 doesn't support WNOHANG, so we just pass 0 opts = getattr(os, 'WNOHANG', 0) try: # TODO: waitpid doesn't work well on windows, we might consider # using WaitForSingleObject(proc._handle, TIMEOUT) # instead. Most notably, the WNOHANG isn't allowed, so # this can hang indefinitely. pid_killed, returncode = os.waitpid(pid, opts) if pid_killed != 0 and returncode != 0: if sig is not None: # high bit in low byte says if core was dumped; we # don't care status, sig = (returncode >> 8, returncode & 0x7f) return True, sig except OSError, e: if e.errno in (errno.ECHILD, errno.ESRCH): # The process doesn't exist anymore return True, None else: raise if i + 1 != count: time.sleep(0.1) return False, None # port 0 means to allocate any port _test_process_args = ['serve', '--port', 'localhost:0'] def test_breakin(self): # Break in to a debugger while bzr is running # we need to test against a command that will wait for # a while -- bzr serve should do proc = self.start_bzr_subprocess(self._test_process_args, env_changes=dict(BZR_SIGQUIT_PDB=None)) # wait for it to get started, and print the 'listening' line proc.stderr.readline() # first sigquit pops into debugger self._send_signal(proc.pid, 'break') # Wait for the debugger to acknowledge the signal reception # Note that it is possible for this to deadlock if the child doesn't # acknowlege the signal and write to stderr. Perhaps we should try # os.read(proc.stderr.fileno())? err = proc.stderr.readline() self.assertContainsRe(err, r'entering debugger') # Try to shutdown cleanly; # Now that the debugger is entered, we can ask him to quit proc.stdin.write("q\n") # But we don't really care if it doesn't. dead, sig = self._wait_for_process(proc.pid, count=3) if not dead: # The process didn't finish, let's kill it. dead, sig = self._wait_for_process(proc.pid, 'kill', count=10) if not dead: # process isn't gone, user will have to hunt it down and kill # it. self.fail("subprocess %d wasn't terminated by repeated SIGKILL" % proc.pid) def test_breakin_harder(self): """SIGQUITting twice ends the process.""" self._dont_SIGQUIT_on_darwin() proc = self.start_bzr_subprocess(self._test_process_args, env_changes=dict(BZR_SIGQUIT_PDB=None)) # wait for it to get started, and print the 'listening' line proc.stderr.readline() # break into the debugger self._send_signal(proc.pid, 'break') # Wait for the debugger to acknowledge the signal reception (since we # want to send a second signal, we ensure it doesn't get lost by # validating the first get received and produce its effect). err = proc.stderr.readline() self.assertContainsRe(err, r'entering debugger') dead, sig = self._wait_for_process(proc.pid, 'break') self.assertTrue(dead) # Either the child was dead before we could read its status, or the # child was dead from the signal we sent it. self.assertTrue(sig in (None, breakin.determine_signal())) def test_breakin_disabled(self): self._dont_SIGQUIT_on_darwin() proc = self.start_bzr_subprocess(self._test_process_args, env_changes=dict(BZR_SIGQUIT_PDB='0')) # wait for it to get started, and print the 'listening' line proc.stderr.readline() # first hit should just kill it self._send_signal(proc.pid, 'break') proc.wait()