mirror of
https://gitlab.freedesktop.org/gstreamer/gstreamer.git
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44 lines
1.6 KiB
Python
44 lines
1.6 KiB
Python
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# Copyright (c) 2018, Matthew Waters <matthew@centricular.com>
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#
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# This program is free software; you can redistribute it and/or
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# modify it under the terms of the GNU Lesser General Public
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# License as published by the Free Software Foundation; either
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# version 2.1 of the License, or (at your option) any later version.
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#
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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# Lesser General Public License for more details.
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#
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# You should have received a copy of the GNU Lesser General Public
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# License along with this program; if not, write to the
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# Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
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# Boston, MA 02110-1301, USA.
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class Signal(object):
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def __init__(self, cont_func=None, accum_func=None):
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self._handlers = []
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if not cont_func:
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# by default continue when None/no return value is provided or
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# True is returned
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cont_func = lambda x: x is None or x
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self.cont_func = cont_func
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# default to accumulating truths
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if not accum_func:
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accum_func = lambda prev, v: prev and v
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self.accum_func = accum_func
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def connect(self, handler):
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self._handlers.append(handler)
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def disconnect(self, handler):
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self._handlers.remove(handler)
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def fire(self, *args):
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ret = None
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for handler in self._handlers:
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ret = self.accum_func(ret, handler(*args))
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if not self.cont_func(ret):
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break
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return ret
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