1# Copyright (C) 2011 Google Inc. All rights reserved.
2#
3# Redistribution and use in source and binary forms, with or without
4# modification, are permitted provided that the following conditions are
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7#     * Redistributions of source code must retain the above copyright
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11# in the documentation and/or other materials provided with the
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28
29"""Simple routines for logging, obtaining thread stack information."""
30
31import sys
32import traceback
33
34
35def log_thread_state(logger, name, thread_id, msg=''):
36    """Log information about the given thread state."""
37    stack = _find_thread_stack(thread_id)
38    assert(stack is not None)
39    logger("")
40    logger("%s (tid %d) %s" % (name, thread_id, msg))
41    _log_stack(logger, stack)
42    logger("")
43
44
45def _find_thread_stack(thread_id):
46    """Returns a stack object that can be used to dump a stack trace for
47    the given thread id (or None if the id is not found)."""
48    for tid, stack in sys._current_frames().items():
49        if tid == thread_id:
50            return stack
51    return None
52
53
54def _log_stack(logger, stack):
55    """Log a stack trace to the logger callback."""
56    for filename, lineno, name, line in traceback.extract_stack(stack):
57        logger('File: "%s", line %d, in %s' % (filename, lineno, name))
58        if line:
59            logger('  %s' % line.strip())
60
61
62def log_traceback(logger, tb):
63    stack = traceback.extract_tb(tb)
64    for frame_str in traceback.format_list(stack):
65        for line in frame_str.split('\n'):
66            if line:
67                logger("  %s" % line)
68