annotate contrib/showstack.py @ 37588:165a77f7ec13

tests: load showstack in test-pull-http.t so network hangs are easier to find

This also gives us some minimal "it loads" coverage on showstack,
which I rather like. showstack doesn't work on Windows per mbarbison,
so it's disabled there.

I added this in service of debugging a hang introduced on Python 3 by
revision a88d68dc3ee8. I'm still not sure what the problem there is,
but this at least gives us a little bit of a chance to figure out
what's going on.

Differential Revision: https://phab.mercurial-scm.org/D3247

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

from __future__ import absolute_import
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 extsetup(ui):
    signal.signal(signal.SIGQUIT, sigshow)
    try:
        signal.signal(signal.SIGINFO, sigshow)
    except AttributeError:
        pass