runtime/RegExpCache.h

   1 /*
   2  * Copyright (C) 2010 University of Szeged
   3  * Copyright (C) 2010 Renata Hodovan (hodovan@inf.u-szeged.hu)
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY UNIVERSITY OF SZEGED ``AS IS'' AND ANY
  16  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  18  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL UNIVERSITY OF SZEGED OR
  19  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  20  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  21  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  22  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  23  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  25  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 #include "RegExp.h"
  29 #include "RegExpKey.h"
  30 #include "UString.h"
  31
  32 #ifndef RegExpCache_h
  33 #define RegExpCache_h
  34
  35 namespace JSC {
  36
  37 class RegExpCache {
  38 public:
  39     PassRefPtr<RegExp> lookupOrCreate(const UString& patternString, const UString& flags);
  40     PassRefPtr<RegExp> create(const UString& patternString, const UString& flags);
  41     RegExpCache(JSGlobalData* globalData);
  42
  43     static bool isCacheable(const UString& patternString) { return patternString.size() < maxCacheablePatternLength; }
  44
  45 private:
  46     static const unsigned maxCacheablePatternLength = 256;
  47     static const int maxCacheableEntries = 32;
  48
  49     typedef HashMap<RegExpKey, RefPtr<RegExp> > RegExpCacheMap;
  50     RegExpKey patternKeyArray[maxCacheableEntries];
  51     RegExpCacheMap m_cacheMap;
  52     JSGlobalData* m_globalData;
  53     int m_nextKeyToEvict;
  54     bool m_isFull;
  55 };
  56
  57 } // namespace JSC
  58
  59 #endif // RegExpCache_h