fast_wildcard_group.h

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/*
 * Copyright 2012 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http:///www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */


#ifndef PAGESPEED_KERNEL_BASE_FAST_WILDCARD_GROUP_H_
#define PAGESPEED_KERNEL_BASE_FAST_WILDCARD_GROUP_H_

#include <vector>
#include "pagespeed/kernel/base/atomic_int32.h"
#include "pagespeed/kernel/base/basictypes.h"
#include "pagespeed/kernel/base/string.h"
#include "pagespeed/kernel/base/string_util.h"

namespace net_instaweb {

class Wildcard;


class FastWildcardGroup {
 public:
  static const int kMinPatterns = 11;

  FastWildcardGroup()
      : rolling_hash_length_(kUncompiled) { }
  FastWildcardGroup(const FastWildcardGroup& src)
      : rolling_hash_length_(kUncompiled) {
    CopyFrom(src);
  }

  ~FastWildcardGroup();
  FastWildcardGroup& operator=(const FastWildcardGroup& other) {
    CopyFrom(other);
    return *this;
  }

  bool Match(const StringPiece& str, bool allow_by_default) const;

  void Allow(const StringPiece& wildcard);

  void Disallow(const StringPiece& wildcard);

  void CopyFrom(const FastWildcardGroup& src);
  void AppendFrom(const FastWildcardGroup& src);

  void Merge(const FastWildcardGroup& src) { AppendFrom(src); }

  GoogleString Signature() const;

  int num_wildcards() const { return wildcards_.size(); }
  bool empty() const { return wildcards_.empty(); }

 private:
  static const int32 kUncompiled = -1;
  static const int32 kDontHash = 0;

  void Uncompile();
  void Clear();
  inline int& pattern_hash_index(uint64 rolling_hash) const;
  void Compile() const;
  void CompileNonTrivial() const;

  std::vector<Wildcard*> wildcards_;
  std::vector<bool> allow_; 

  mutable std::vector<uint64> rolling_hashes_; 
  mutable std::vector<int> effective_indices_; 
  mutable std::vector<int> wildcard_only_indices_; 
  mutable std::vector<int> pattern_hash_index_; 
  mutable AtomicInt32 rolling_hash_length_;

};

}  

#endif