netwerk/dns/IDNBlocklistUtils.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #ifndef IDNBlocklistUtils_h__
   7 #define IDNBlocklistUtils_h__
   8
   9 #include <utility>
  10 #include "nsTArray.h"
  11
  12 namespace mozilla {
  13 namespace net {
  14
  15 // A blocklist range is defined as all of the characters between:
  16 // { firstCharacterInRange, lastCharacterInRange }
  17 using BlocklistRange = std::pair<char16_t, char16_t>;
  18
  19 // Used to perform a binary search of the needle in the sorted array of pairs
  20 class BlocklistPairToCharComparator {
  21  public:
  22   bool Equals(const BlocklistRange& pair, char16_t needle) const {
  23     // If the needle is between pair.first and pair.second it
  24     // is part of the range.
  25     return pair.first <= needle && needle <= pair.second;
  26   }
  27
  28   bool LessThan(const BlocklistRange& pair, char16_t needle) const {
  29     // The needle has to be larger than the second value,
  30     // otherwise it may be equal.
  31     return pair.second < needle;
  32   }
  33 };
  34
  35 // Used to sort the array of pairs
  36 class BlocklistEntryComparator {
  37  public:
  38   bool Equals(const BlocklistRange& a, const BlocklistRange& b) const {
  39     return a.first == b.first && a.second == b.second;
  40   }
  41
  42   bool LessThan(const BlocklistRange& a, const BlocklistRange& b) const {
  43     return a.first < b.first;
  44   }
  45 };
  46
  47 // Returns true if the char can be found in the blocklist
  48 inline bool CharInBlocklist(char16_t aChar,
  49                             const nsTArray<BlocklistRange>& aBlocklist) {
  50   return aBlocklist.ContainsSorted(aChar, BlocklistPairToCharComparator());
  51 }
  52
  53 // Initializes the blocklist based on the statically defined list and the
  54 // values of the following preferences:
  55 //     - network.IDN.extra_allowed_chars
  56 //     - network.IDN.extra_blocked_chars
  57 void InitializeBlocklist(nsTArray<BlocklistRange>& aBlocklist);
  58
  59 void RemoveCharFromBlocklist(char16_t aChar,
  60                              nsTArray<BlocklistRange>& aBlocklist);
  61
  62 }  // namespace net
  63 }  // namespace mozilla
  64
  65 #endif  // IDNBlocklistUtils_h__