gecko/toolkit/components/url-classifier/nsUrlClassifierPrefixSet.h

//* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef nsUrlClassifierPrefixSet_h_
#define nsUrlClassifierPrefixSet_h_

#include "nsISupportsUtils.h"
#include "nsID.h"
#include "nsIFile.h"
#include "nsIMutableArray.h"
#include "nsIUrlClassifierPrefixSet.h"
#include "nsTArray.h"
#include "nsToolkitCompsCID.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/Mutex.h"
#include "mozilla/CondVar.h"
#include "mozilla/FileUtils.h"

class nsIMemoryReporter;

class nsUrlClassifierPrefixSet : public nsIUrlClassifierPrefixSet
{
public:
  nsUrlClassifierPrefixSet();
  virtual ~nsUrlClassifierPrefixSet();

  NS_IMETHOD Init(const nsACString& aName);
  NS_IMETHOD SetPrefixes(const uint32_t* aArray, uint32_t aLength);
  NS_IMETHOD GetPrefixes(uint32_t* aCount, uint32_t** aPrefixes);
  NS_IMETHOD Contains(uint32_t aPrefix, bool* aFound);
  NS_IMETHOD IsEmpty(bool* aEmpty);
  NS_IMETHOD LoadFromFile(nsIFile* aFile);
  NS_IMETHOD StoreToFile(nsIFile* aFile);

  NS_DECL_ISUPPORTS

  // Return the estimated size of the set on disk and in memory,
  // in bytes
  size_t SizeOfIncludingThis(mozilla::MallocSizeOf mallocSizeOf);

protected:
  static const uint32_t DELTAS_LIMIT = 100;
  static const uint32_t MAX_INDEX_DIFF = (1 << 16);
  static const uint32_t PREFIXSET_VERSION_MAGIC = 1;

  nsCOMPtr<nsIMemoryReporter> mReporter;

  nsresult MakePrefixSet(const uint32_t* aArray, uint32_t aLength);
  uint32_t BinSearch(uint32_t start, uint32_t end, uint32_t target);
  nsresult LoadFromFd(mozilla::AutoFDClose& fileFd);
  nsresult StoreToFd(mozilla::AutoFDClose& fileFd);

  // boolean indicating whether |setPrefixes| has been
  // called with a non-empty array.
  bool mHasPrefixes;
  // the prefix for each index.
  FallibleTArray<uint32_t> mIndexPrefixes;
  // the value corresponds to the beginning of the run
  // (an index in |_deltas|) for the index
  FallibleTArray<uint32_t> mIndexStarts;
  // array containing deltas from indices.
  FallibleTArray<uint16_t> mDeltas;
};

#endif