view contrib/showstack.py @ 46530:b994db7c4d1e stable

narrow: fix flaky behavior described in issue6150

This has been plaguing the CI for a good while, and it doesn't appear to have
an easy fix proposed yet. The solution in this change is to always do an
unambiguous (but expensive) lookup in case of comparison. This should always
be correct, albeit suboptimal.

Differential Revision: https://phab.mercurial-scm.org/D10034

# showstack.py - extension to dump a Python stack trace on signal
#
# binds to both SIGQUIT (Ctrl-\) and SIGINFO (Ctrl-T on BSDs)
r"""dump stack trace when receiving SIGQUIT (Ctrl-\) or SIGINFO (Ctrl-T on BSDs)
"""

from __future__ import absolute_import, print_function
import signal
import sys
import traceback


def sigshow(*args):
    sys.stderr.write("\n")
    traceback.print_stack(args[1], limit=10, file=sys.stderr)
    sys.stderr.write("----\n")


def sigexit(*args):
    sigshow(*args)
    print('alarm!')
    sys.exit(1)


def extsetup(ui):
    signal.signal(signal.SIGQUIT, sigshow)
    signal.signal(signal.SIGALRM, sigexit)
    try:
        signal.signal(signal.SIGINFO, sigshow)
    except AttributeError:
        pass