annotate contrib/showstack.py @ 29783:5d44197c208b

profiling: make profiling functions context managers (API)

This makes profiling more flexible since we can now call multiple
functions when a profiler is active. But the real reason for this
is to enable a future consumer to profile a function that returns
a generator. We can't do this from the profiling function itself
because functions can either be generators or have return values:
they can't be both. So therefore it isn't possible to have a generic
profiling function that can both consume and re-emit a generator
and return a value.

# showstack.py - extension to dump a Python stack trace on signal
#
# binds to both 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