sdk/platform-tools/systrace/catapult/telemetry/telemetry/internal/util/global_hooks.py

   1 # Copyright 2014 The Chromium Authors. All rights reserved.
   2 # Use of this source code is governed by a BSD-style license that can be
   3 # found in the LICENSE file.
   4
   5 """Hooks that apply globally to all scripts that import or use Telemetry."""
   6 import signal
   7 import sys
   8
   9 from telemetry.internal.util import exception_formatter
  10
  11
  12 def InstallHooks():
  13   InstallUnhandledExceptionFormatter()
  14   InstallStackDumpOnSigusr1()
  15   InstallTerminationHook()
  16
  17 def InstallUnhandledExceptionFormatter():
  18   """Print prettier exceptions that also contain the stack frame's locals."""
  19   sys.excepthook = exception_formatter.PrintFormattedException
  20
  21
  22 def InstallStackDumpOnSigusr1():
  23   """Catch SIGUSR1 and print a stack trace."""
  24   # Windows doesn't define SIGUSR1.
  25   if not hasattr(signal, 'SIGUSR1'):
  26     return
  27
  28   def PrintDiagnostics(_, stack_frame):
  29     exception_string = 'SIGUSR1 received, printed stack trace'
  30     exception_formatter.PrintFormattedFrame(stack_frame, exception_string)
  31   signal.signal(signal.SIGUSR1, PrintDiagnostics)
  32
  33
  34 def InstallTerminationHook():
  35   """Catch SIGTERM, print a stack trace, and exit."""
  36   def PrintStackAndExit(sig, stack_frame):
  37     exception_string = 'Received signal %s, exiting' % sig
  38     exception_formatter.PrintFormattedFrame(stack_frame, exception_string)
  39     sys.exit(-1)
  40   signal.signal(signal.SIGTERM, PrintStackAndExit)