projects / babeltrace.git / blame
| Commit | Line | Data |
|---|---|---|
| d2d857a8 MJ |
1 | # |
| 2 | # Copyright (C) 2019 EfficiOS Inc. | |
| 3 | # | |
| 4 | # This program is free software; you can redistribute it and/or | |
| 5 | # modify it under the terms of the GNU General Public License | |
| 6 | # as published by the Free Software Foundation; only version 2 | |
| 7 | # of the License. | |
| 8 | # | |
| 9 | # This program is distributed in the hope that it will be useful, | |
| 10 | # but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 11 | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| 12 | # GNU General Public License for more details. | |
| 13 | # | |
| 14 | # You should have received a copy of the GNU General Public License | |
| 15 | # along with this program; if not, write to the Free Software | |
| 16 | # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
| 17 | # | |
| 18 | ||
| fbbe9302 SM |
19 | import bt2 |
| 20 | ||
| 21 | # Run callable `func` in the context of a component's __init__ method. The | |
| 22 | # callable is passed the Component being instantiated. | |
| 23 | # | |
| 24 | # The value returned by the callable is returned by run_in_component_init. | |
| 25 | ||
| 26 | def run_in_component_init(func): | |
| 27 | class MySink(bt2._UserSinkComponent): | |
| 28 | def __init__(self, params): | |
| 29 | nonlocal res_bound | |
| 30 | res_bound = func(self) | |
| 31 | ||
| 32 | def _consume(self): | |
| 33 | pass | |
| 34 | ||
| 35 | g = bt2.Graph() | |
| 36 | res_bound = None | |
| 37 | g.add_component(MySink, 'comp') | |
| 38 | ||
| 39 | # We deliberately use a different variable for returning the result than | |
| 40 | # the variable bound to the MySink.__init__ context and delete res_bound. | |
| 41 | # The MySink.__init__ context stays alive until the end of the program, so | |
| 42 | # if res_bound were to still point to our result, it would contribute an | |
| 43 | # unexpected reference to the refcount of the result, from the point of view | |
| 44 | # of the user of this function. It would then affect destruction tests, | |
| 45 | # for example, which want to test what happens when the refcount of a Python | |
| 46 | # object reaches 0. | |
| 47 | ||
| 48 | res = res_bound | |
| 49 | del res_bound | |
| 50 | return res | |
| 51 | ||
| 52 | # Create an empty trace class with default values. | |
| 53 | ||
| 54 | def get_default_trace_class(): | |
| 55 | def f(comp_self): | |
| 56 | return comp_self._create_trace_class() | |
| 57 | ||
| 58 | return run_in_component_init(f) |