#!/usr/bin/env python # Copyright (C) 2005, 2006, 2007, 2008 Nikolas Zimmermann <zimmermann@kde.org> # Copyright (C) 2006 Anders Carlsson <andersca@mac.com> # Copyright (C) 2006, 2007 Samuel Weinig <sam@webkit.org> # Copyright (C) 2006 Alexey Proskuryakov <ap@webkit.org> # Copyright (C) 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved. # Copyright (C) 2009 Cameron McCormack <cam@mcc.id.au> # Copyright (C) Research In Motion Limited 2010. All rights reserved. # Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies) # Copyright (C) 2011 Patrick Gansterer <paroga@webkit.org> # Copyright (C) 2012 Ericsson AB. All rights reserved. # # This library is free software; you can redistribute it and/or # modify it under the terms of the GNU Library General Public # License as published by the Free Software Foundation; either # version 2 of the License, or (at your option) any later version. # # This library is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU # Library General Public License for more details. # # You should have received a copy of the GNU Library General Public License # along with this library; see the file COPYING.LIB. If not, write to # the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, # Boston, MA 02110-1301, USA. def stringHash(str): # Implements Paul Hsieh's SuperFastHash - http://www.azillionmonkeys.com/qed/hash.html # LChar data is interpreted as Latin-1-encoded (zero extended to 16 bits). stringHashingStartValue = 0x9E3779B9 twoTo32 = 4294967296 hash = stringHashingStartValue strLength = len(str) characterPairs = strLength / 2 remainder = strLength & 1 # Main loop while characterPairs > 0: hash = hash + ord(str[0]) tmp = (ord(str[1]) << 11) ^ hash hash = ((hash << 16) % twoTo32) ^ tmp str = str[2:] hash = hash + (hash >> 11) hash = hash % twoTo32 characterPairs = characterPairs - 1 # Handle end case if remainder: hash = hash + ord(str[0]) hash = hash ^ ((hash << 11) % twoTo32) hash = hash + (hash >> 17) hash = hash ^ (hash << 3) hash = hash + (hash >> 5) hash = hash % twoTo32 hash = hash ^ ((hash << 2) % twoTo32) hash = hash + (hash >> 15) hash = hash % twoTo32 hash = hash ^ ((hash << 10) % twoTo32) hash = hash & 0xffffff if not hash: hash = 0x800000 return hash