def Wait(self):
# This is a list of async jobs
while True:
try:
pid, status = posix.wait()
except OSError as e:
#log('wait() error: %s', e)
if e.errno == errno.ECHILD:
return False # nothing to wait for caller should stop
else:
# We should never get here. EINTR was handled by the 'posix'
# module. The only other error is EINVAL, which doesn't apply to
# this call.
raise
else:
break # no exception thrown, so no need to retry
#log('WAIT got %s %s', pid, status)
# TODO: Also handle WIFSTOPPED case?
if posix.WIFSIGNALED(status):
status = 128 + posix.WTERMSIG(status)
# Print newline after Ctrl-C.
if posix.WTERMSIG(status) == signal.SIGINT:
print()
elif posix.WIFEXITED(status):
status = posix.WEXITSTATUS(status)
#log('exit status: %s', status)
# This could happen via coding error. But this may legitimately happen
# if a grandchild outlives the child (its parent). Then it is reparented
# under this process, so we might receive notification of its exit, even
# though we didn't start it. We can't have any knowledge of such
# processes, so print a warning.
if pid not in self.callbacks:
ui.Stderr("osh: PID %d stopped, but osh didn't start it", pid)
return True # caller should keep waiting
callback = self.callbacks.pop(pid)
callback(pid, status)
self.last_status = status # for wait -n
return True # caller should keep waiting
def WaitForOne(self):
# type: () -> bool
"""Wait until the next process returns (or maybe Ctrl-C).
Returns:
True if we got a notification, or False if there was nothing to wait for.
In the interactive shell, we return True if we get a Ctrl-C, so the
caller will try again.
"""
# This is a list of async jobs
try:
# -1 makes it like wait(), which waits for any process.
# NOTE: WUNTRACED is necessary to get stopped jobs. What about
# WCONTINUED?
pid, status = posix.waitpid(-1, posix.WUNTRACED)
except OSError as e:
#log('wait() error: %s', e)
if e.errno == errno_.ECHILD:
return False # nothing to wait for caller should stop
else:
# We should never get here. EINTR was handled by the 'posix'
# module. The only other error is EINVAL, which doesn't apply to
# this call.
raise
except KeyboardInterrupt:
# NOTE: Another way to handle this is to disable SIGINT when a process is
# running. Not sure if there's any real difference. bash and dash
# handle SIGINT pretty differently.
if self.exec_opts.interactive():
# Caller should keep waiting. If we run 'sleep 3' and hit Ctrl-C, both
# processes will get SIGINT, but the shell has to wait again to get the
# exit code.
return True
else:
raise # abort a batch script
#log('WAIT got %s %s', pid, status)
# All child processes are suppoed to be in this doc. But this may
# legitimately happen if a grandchild outlives the child (its parent).
# Then it is reparented under this process, so we might receive
# notification of its exit, even though we didn't start it. We can't have
# any knowledge of such processes, so print a warning.
if pid not in self.job_state.child_procs:
stderr_line("osh: PID %d stopped, but osh didn't start it", pid)
return True # caller should keep waiting
proc = self.job_state.child_procs[pid]
if posix.WIFSIGNALED(status):
status = 128 + posix.WTERMSIG(status)
# Print newline after Ctrl-C.
if posix.WTERMSIG(status) == signal.SIGINT:
print('')
proc.WhenDone(pid, status)
elif posix.WIFEXITED(status):
status = posix.WEXITSTATUS(status)
#log('exit status: %s', status)
proc.WhenDone(pid, status)
elif posix.WIFSTOPPED(status):
#sig = posix.WSTOPSIG(status)
# TODO: Do something nicer here. Implement 'fg' command.
# Show in jobs list.
log('')
log('[PID %d] Stopped', pid)
self.job_state.NotifyStopped(
pid) # show in 'jobs' list, enable 'fg'
proc.WhenStopped()
self.last_status = status # for wait -n
return True # caller should keep waiting