view contrib/showstack.py @ 44382:f0027a3dd7cb

revlog-compression: update the config to be a list

format.revlog-compression is now a list of engine, the first supported one is to
be used. Doing this have several benefits:

1) this is fully backward compatible, config using a single entry will be read
as a single item list, not changing any behavior.

2) This open the way to use zstd by default without impacting platform were it
is not available. This will be done in a later changesets.

Using zstd provide a significant performance boost explained in : bb271ec2fbfb.
However zstd is not available in some cases, A notable example is the `--pure`
version of Mercurial which doesn't come with zstd support.

Differential Revision: https://phab.mercurial-scm.org/D8148

# 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