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# Copyright (c) 2012 Canonical
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# This file is part of Checkbox.
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# Storm is free software; you can redistribute it and/or modify
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# it under the terms of the GNU Lesser General Public License as
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# published by the Free Software Foundation; either version 2.1 of
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# the License, or (at your option) any later version.
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# Storm 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 Lesser General Public License for more details.
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# You should have received a copy of the GNU Lesser General Public License
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# along with this program. If not, see <http://www.gnu.org/licenses/>.
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from checkbox.journal.event import (
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" ctime=(?P<ctime>\d+)"
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" sequence=(?P<sequence>\d+)"
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" size=(?P<size>\d+)L?"
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" events=(?P<events>\d+)L?"
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" offset=(?P<offset>\d+)L?"
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" event_offset=(?P<event_offset>\d+)L?")
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JOURNAL_RE = re.compile(JOURNAL_PATTERN)
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"""Simple class to extract info from a journal header event."""
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def __init__(self, other=None):
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def copyFrom(self, other):
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"""Copy the parameters from another header object into this one.
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:param other: Other header object.
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self.sequence = other.sequence
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self.ctime = other.ctime
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self.size = other.size
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self.num_events = other.num_events
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self.file_offset = other.file_offset
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self.event_offset = other.event_offset
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self._valid = other._valid
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"""Return true if the header is valid."""
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def incrementSequence(self):
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"""Increment the sequence number."""
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def addFileOffset(self, offset):
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"""Add to the file offset.
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:param offset: Offset to add.
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self.file_offset += offset
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def addEventOffset(self, offset):
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"""Add to the event offset.
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:param offset: Offset to add.
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self.event_offset += offset
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def extractEvent(self, event):
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"""Extract data from an event and update the header.
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:param event: Event from which to extract.
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if event.type != EventType.GENERIC:
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return EventOutcome.NO_EVENT
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match = JOURNAL_RE.match(event.data)
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return EventOutcome.NO_EVENT
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self.ctime = int(match.group("ctime"))
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self.id = match.group("id")
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self.sequence = int(match.group("sequence"))
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self.size = int(match.group("size"))
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self.num_events = int(match.group("events"))
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self.file_offset = int(match.group("offset"))
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self.event_offset = int(match.group("event_offset"))
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return EventOutcome.OK
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class HeaderReader(Header):
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def read(self, reader):
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"""Read the header from a file.
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:param reader: Journal reader object.
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outcome = reader.readEvent(event)
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if outcome != EventOutcome.OK:
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if event.type != EventType.GENERIC:
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return EventOutcome.NO_EVENT
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return self.extractEvent(event)
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class HeaderWriter(Header):
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def write(self, writer, file=None):
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"""Write the header to a file.
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:param reader: Journal writer object.
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event = Event(EventType.GENERIC)
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if not self.generateEvent(event):
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return EventOutcome.UNKNOWN_ERROR
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return writer.writeGlobalEvent(event, file, True)
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def generateEvent(self, event):
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"""Generate a header event.
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:param event: Generic event to contain the header data.
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" event_offset=%d" % (
added
removed
checkbox/journal/header.py
