components/autofill/core/browser/autofill_regexes.cc

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "components/autofill/core/browser/autofill_regexes.h"
   6
   7 #include "base/containers/scoped_ptr_hash_map.h"
   8 #include "base/logging.h"
   9 #include "base/memory/scoped_ptr.h"
  10 #include "base/memory/singleton.h"
  11 #include "base/strings/string16.h"
  12 #include "third_party/icu/source/i18n/unicode/regex.h"
  13
  14 namespace {
  15
  16 // A singleton class that serves as a cache of compiled regex patterns.
  17 class AutofillRegexes {
  18  public:
  19   static AutofillRegexes* GetInstance();
  20
  21   // Returns the compiled regex matcher corresponding to |pattern|.
  22   icu::RegexMatcher* GetMatcher(const base::string16& pattern);
  23
  24  private:
  25   AutofillRegexes();
  26   ~AutofillRegexes();
  27   friend struct DefaultSingletonTraits<AutofillRegexes>;
  28
  29   // Maps patterns to their corresponding regex matchers.
  30   base::ScopedPtrHashMap<base::string16, icu::RegexMatcher> matchers_;
  31
  32   DISALLOW_COPY_AND_ASSIGN(AutofillRegexes);
  33 };
  34
  35 // static
  36 AutofillRegexes* AutofillRegexes::GetInstance() {
  37   return Singleton<AutofillRegexes>::get();
  38 }
  39
  40 AutofillRegexes::AutofillRegexes() {
  41 }
  42
  43 AutofillRegexes::~AutofillRegexes() {
  44 }
  45
  46 icu::RegexMatcher* AutofillRegexes::GetMatcher(const base::string16& pattern) {
  47   auto it = matchers_.find(pattern);
  48   if (it == matchers_.end()) {
  49     const icu::UnicodeString icu_pattern(pattern.data(), pattern.length());
  50
  51     UErrorCode status = U_ZERO_ERROR;
  52     scoped_ptr<icu::RegexMatcher> matcher(
  53         new icu::RegexMatcher(icu_pattern, UREGEX_CASE_INSENSITIVE, status));
  54     DCHECK(U_SUCCESS(status));
  55
  56     auto result = matchers_.add(pattern, matcher.Pass());
  57     DCHECK(result.second);
  58     it = result.first;
  59   }
  60   return it->second;
  61 }
  62
  63 }  // namespace
  64
  65 namespace autofill {
  66
  67 bool MatchesPattern(const base::string16& input,
  68                     const base::string16& pattern) {
  69   icu::RegexMatcher* matcher =
  70       AutofillRegexes::GetInstance()->GetMatcher(pattern);
  71   icu::UnicodeString icu_input(input.data(), input.length());
  72   matcher->reset(icu_input);
  73
  74   UErrorCode status = U_ZERO_ERROR;
  75   UBool match = matcher->find(0, status);
  76   DCHECK(U_SUCCESS(status));
  77   return match == TRUE;
  78 }
  79
  80 }  // namespace autofill