src/chrome/browser/language_usage_metrics.cc

   1 // Copyright (c) 2011 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 "chrome/browser/language_usage_metrics.h"
   6
   7 #include <algorithm>
   8
   9 #include "base/metrics/sparse_histogram.h"
  10 #include "base/strings/string_tokenizer.h"
  11 #include "base/strings/string_util.h"
  12
  13 namespace {
  14 void RecordAcceptLanguage(int language_code) {
  15   UMA_HISTOGRAM_SPARSE_SLOWLY("LanguageUsage.AcceptLanguage",
  16                               language_code);
  17 }
  18 }  // namespace
  19
  20 // static
  21 void LanguageUsageMetrics::RecordAcceptLanguages(
  22     const std::string& accept_languages) {
  23   std::set<int> languages;
  24   ParseAcceptLanguages(accept_languages, &languages);
  25   std::for_each(languages.begin(), languages.end(), RecordAcceptLanguage);
  26 }
  27
  28 // static
  29 void LanguageUsageMetrics::RecordApplicationLanguage(
  30     const std::string& application_locale) {
  31   const int language_code = ToLanguageCode(application_locale);
  32   if (language_code != 0)
  33     UMA_HISTOGRAM_SPARSE_SLOWLY("LanguageUsage.ApplicationLanguage",
  34                                 language_code);
  35 }
  36
  37 // static
  38 int LanguageUsageMetrics::ToLanguageCode(const std::string& locale) {
  39   base::StringTokenizer parts(locale, "-_");
  40   if (!parts.GetNext())
  41     return 0;
  42
  43   std::string language_part = parts.token();
  44   StringToLowerASCII(&language_part);
  45
  46   int language_code = 0;
  47   for (std::string::iterator it = language_part.begin();
  48        it != language_part.end(); ++it) {
  49     char ch = *it;
  50     if (ch < 'a' || 'z' < ch)
  51       return 0;
  52
  53     language_code <<= 8;
  54     language_code += ch;
  55   }
  56
  57   return language_code;
  58 }
  59
  60 // static
  61 void LanguageUsageMetrics::ParseAcceptLanguages(
  62     const std::string& accept_languages,
  63     std::set<int>* languages) {
  64   languages->clear();
  65   base::StringTokenizer locales(accept_languages, ",");
  66   while (locales.GetNext()) {
  67     const int language_code = ToLanguageCode(locales.token());
  68     if (language_code != 0)
  69       languages->insert(language_code);
  70   }
  71 }