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forestbondforestbond
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Add support for the Generic Event Extension.
While most of this functionality is implemented in the new "ge" extension module, some changes to the core protocol implementation were also required due to the need to read event packets longer than 32 bytes.
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3 files changed

+141
-14
lines changed

3 files changed

+141
-14
lines changed

‎Xlib/ext/__init__.py‎

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Original file line numberDiff line numberDiff line change
@@ -21,6 +21,9 @@
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# protocol. extmod is the name of the module in this package.
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__extensions__ = [
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# We load this first so other extensions can register generic event data
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# structures.
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('Generic Event Extension', 'ge'),
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('XTEST', 'xtest'),
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('SHAPE', 'shape'),
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('XINERAMA', 'xinerama'),

‎Xlib/ext/ge.py‎

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@@ -0,0 +1,109 @@
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# Xlib.ext.ge -- Generic Event extension module
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#
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# Copyright (C) 2012 Outpost Embedded, LLC
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# Forest Bond <forest.bond@rapidrollout.com>
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#
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation; either version 2 of the License, or
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# (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
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# GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the Free Software
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# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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'''
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ge - Generic Event Extension
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'''
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from Xlib.protocol import rq
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extname = 'Generic Event Extension'
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GenericEventCode = 35
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class GEQueryVersion(rq.ReplyRequest):
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_request = rq.Struct(
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rq.Card8('opcode'),
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rq.Opcode(0),
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rq.RequestLength(),
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rq.Card32('major_version'),
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rq.Card32('minor_version'),
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)
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_reply = rq.Struct(
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rq.ReplyCode(),
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rq.Pad(1),
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rq.Card16('sequence_number'),
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rq.ReplyLength(),
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rq.Card32('major_version'),
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rq.Card32('minor_version'),
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rq.Pad(16),
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)
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def query_version(self):
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return GEQueryVersion(
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display=self.display,
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opcode=self.display.get_extension_major(extname),
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major_version=1,
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minor_version=0,
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)
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class GenericEvent(rq.Event):
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_code = GenericEventCode
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_fields = rq.Struct(
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rq.Card8('type'),
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rq.Card8('extension'),
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rq.Card16('sequence_number'),
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rq.Card32('length'),
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rq.Card16('evtype'),
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# Some generic events make use of this space, but with
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# others the data is simply discarded. In any case we
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# don't need to explicitly pad this out as we are
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# always given at least 32 bytes and we save
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# everything after the first ten as the "data" field.
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#rq.Pad(22),
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)
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def __init__(self, binarydata = None, display = None, **keys):
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if binarydata:
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data = binarydata[10:]
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binarydata = binarydata[:10]
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else:
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data = ''
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rq.Event.__init__(
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self,
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binarydata=binarydata,
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display=display,
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**keys
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)
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if display:
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ge_event_data = getattr(display, 'ge_event_data', None)
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if ge_event_data:
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estruct = ge_event_data.get((self.extension, self.evtype), None)
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if estruct:
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data, _ = estruct.parse_binary(data, display)
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self._data['data'] = data
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def add_event_data(self, extension, evtype, estruct):
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if not hasattr(self.display, 'ge_event_data'):
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self.display.ge_event_data = {}
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self.display.ge_event_data[(extension, evtype)] = estruct
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def init(disp, info):
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disp.extension_add_method('display', 'ge_query_version', query_version)
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disp.extension_add_method('display', 'ge_add_event_data', add_event_data)
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disp.extension_add_event(GenericEventCode, GenericEvent)

‎Xlib/protocol/display.py‎

Lines changed: 29 additions & 14 deletions
Original file line numberDiff line numberDiff line change
@@ -27,6 +27,7 @@
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# Xlib modules
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from Xlib import error
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from Xlib.ext import ge
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from Xlib.support import lock, connect
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@@ -639,34 +640,39 @@ def parse_response(self, request):
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# Parse ordinary server response
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gotreq = 0
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while 1:
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# Are we're waiting for additional data for a request response?
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if self.data_recv:
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# Check the first byte to find out what kind of response it is
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rtype = ord(self.data_recv[0])
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# Are we're waiting for additional data for the current packet?
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if self.recv_packet_len:
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if len(self.data_recv) < self.recv_packet_len:
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return gotreq
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else:
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gotreq = self.parse_request_response(request) or gotreq
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if rtype == 1:
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gotreq = self.parse_request_response(request) or gotreq
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elif rtype & 0x7f == ge.GenericEventCode:
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self.parse_event_response(rtype)
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else:
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raise AssertionError(rtype)
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# Every response is at least 32 bytes long, so don't bother
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# until we have recieved that much
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if len(self.data_recv) < 32:
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return gotreq
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655-
# Check the first byte to find out what kind of response it is
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rtype = ord(self.data_recv[0])
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# Error resposne
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if rtype == 0:
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gotreq = self.parse_error_response(request) or gotreq
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662-
# Request response
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elif rtype == 1:
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# Request response or generic event.
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elif rtype == 1 or rtype & 0x7f == ge.GenericEventCode:
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# Set reply length, and loop around to see if
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# we have got the full response
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rlen = int(struct.unpack('=L', self.data_recv[4:8])[0])
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self.recv_packet_len = 32 + rlen * 4
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669-
# Else event response
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# Else non-generic event
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else:
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self.parse_event_response(rtype)
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@@ -752,16 +758,25 @@ def parse_request_response(self, request):
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def parse_event_response(self, etype):
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# Skip bit 8 at lookup, that is set if this event came from an
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# SendEvent
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estruct = self.event_classes.get(etype & 0x7f, event.AnyEvent)
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# Skip bit 8, that is set if this event came from an SendEvent
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etype = etype & 0x7f
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if etype == ge.GenericEventCode:
765+
length = self.recv_packet_len
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else:
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length = 32
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estruct = self.event_classes.get(etype, event.AnyEvent)
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if type(estruct) == dict:
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# this etype refers to a set of sub-events with individual subcodes
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estruct = estruct[ord(self.data_recv[1])]
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762-
e = estruct(display = self, binarydata = self.data_recv[:32])
774+
e = estruct(display = self, binarydata = self.data_recv[:length])
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764-
self.data_recv = buffer(self.data_recv, 32)
776+
if etype == ge.GenericEventCode:
777+
self.recv_packet_len = 0
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779+
self.data_recv = buffer(self.data_recv, length)
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766781
# Drop all requests having an error handler,
767782
# but which obviously succeded.

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