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lightning-sunbird  0.9+nobinonly
nsTHashtable.cpp
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00001 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
00002 /* ***** BEGIN LICENSE BLOCK *****
00003  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
00004  *
00005  * The contents of this file are subject to the Mozilla Public License Version
00006  * 1.1 (the "License"); you may not use this file except in compliance with
00007  * the License. You may obtain a copy of the License at
00008  * http://www.mozilla.org/MPL/
00009  *
00010  * Software distributed under the License is distributed on an "AS IS" basis,
00011  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
00012  * for the specific language governing rights and limitations under the
00013  * License.
00014  *
00015  * The Original Code is C++ hashtable templates.
00016  *
00017  * The Initial Developer of the Original Code is
00018  * Benjamin Smedberg.
00019  * Portions created by the Initial Developer are Copyright (C) 2002
00020  * the Initial Developer. All Rights Reserved.
00021  *
00022  * Contributor(s):
00023  *
00024  * Alternatively, the contents of this file may be used under the terms of
00025  * either the GNU General Public License Version 2 or later (the "GPL"), or
00026  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
00027  * in which case the provisions of the GPL or the LGPL are applicable instead
00028  * of those above. If you wish to allow use of your version of this file only
00029  * under the terms of either the GPL or the LGPL, and not to allow others to
00030  * use your version of this file under the terms of the MPL, indicate your
00031  * decision by deleting the provisions above and replace them with the notice
00032  * and other provisions required by the GPL or the LGPL. If you do not delete
00033  * the provisions above, a recipient may use your version of this file under
00034  * the terms of any one of the MPL, the GPL or the LGPL.
00035  *
00036  * ***** END LICENSE BLOCK ***** */
00037 
00038 #include "nsTHashtable.h"
00039 #include "nsHashKeys.h"
00040 
00041 PRUint32
00042 HashString( const nsAString& aStr )
00043 {
00044   PRUint32 code = 0;
00045 
00046 #ifdef MOZILLA_INTERNAL_API
00047   nsAString::const_iterator begin, end;
00048   aStr.BeginReading(begin);
00049   aStr.EndReading(end);
00050 #else
00051   const PRUnichar *begin, *end;
00052   PRUint32 len = NS_StringGetData(aStr, &begin);
00053   end = begin + len;
00054 #endif
00055 
00056   while (begin != end) {
00057     code = (code>>28) ^ (code<<4) ^ PRUint32(*begin);
00058     ++begin;
00059   }
00060 
00061   return code;
00062 }
00063 
00064 PRUint32
00065 HashString( const nsACString& aStr )
00066 {
00067   PRUint32 code = 0;
00068 
00069 #ifdef MOZILLA_INTERNAL_API
00070   nsACString::const_iterator begin, end;
00071   aStr.BeginReading(begin);
00072   aStr.EndReading(end);
00073 #else
00074   const char *begin, *end;
00075   PRUint32 len = NS_CStringGetData(aStr, &begin);
00076   end = begin + len;
00077 #endif
00078 
00079   while (begin != end) {
00080     code = (code>>28) ^ (code<<4) ^ PRUint32(*begin);
00081     ++begin;
00082   }
00083 
00084   return code;
00085 }
00086 
00087 PRUint32
00088 HashCString(const char *str)
00089 {
00090   PRUint32 code = 0;
00091 
00092   while (*str) {
00093     code = (code>>28) ^ (code<<4) ^ PRUint32(*str);
00094     ++str;
00095   }
00096 
00097   return code;
00098 }
00099 
00100 PR_IMPLEMENT(PLDHashOperator)
00101 PL_DHashStubEnumRemove(PLDHashTable    *table,
00102                                        PLDHashEntryHdr *entry,
00103                                        PRUint32         ordinal,
00104                                        void            *userarg)
00105 {
00106   return PL_DHASH_REMOVE;
00107 }
00108 
00109 PRUint32 nsIDHashKey::HashKey(const nsID* id)
00110 {
00111   PRUint32 h = id->m0;
00112   PRUint32 i;
00113 
00114   h = (h>>28) ^ (h<<4) ^ id->m1;
00115   h = (h>>28) ^ (h<<4) ^ id->m2;
00116 
00117   for (i = 0; i < 8; i++)
00118     h = (h>>28) ^ (h<<4) ^ id->m3[i];
00119 
00120   return h;
00121 }