chromeos/settings/timezone_settings_helper.cc

   1 // Copyright 2015 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 "chromeos/settings/timezone_settings_helper.h"
   6
   7 #include "base/logging.h"
   8 #include "chromeos/chromeos_export.h"
   9
  10 namespace chromeos {
  11 namespace system {
  12
  13 CHROMEOS_EXPORT const icu::TimeZone* GetKnownTimezoneOrNull(
  14     const icu::TimeZone& timezone,
  15     const std::vector<icu::TimeZone*>& timezone_list) {
  16   const icu::TimeZone* known_timezone = NULL;
  17   icu::UnicodeString id, canonical_id;
  18   timezone.getID(id);
  19   UErrorCode status = U_ZERO_ERROR;
  20   icu::TimeZone::getCanonicalID(id, canonical_id, status);
  21   DCHECK(U_SUCCESS(status));
  22   for (const auto* entry : timezone_list) {
  23     if (*entry == timezone)
  24       return entry;
  25     // Compare the canonical IDs as well.
  26     // For instance, Asia/Ulan_Bator -> Asia/Ulaanbaatar or
  27     // Canada/Pacific -> America/Vancouver
  28     icu::UnicodeString entry_id, entry_canonical_id;
  29     entry->getID(entry_id);
  30     icu::TimeZone::getCanonicalID(entry_id, entry_canonical_id, status);
  31     DCHECK(U_SUCCESS(status));
  32     if (entry_canonical_id == canonical_id)
  33       return entry;
  34     // Last resort: If no match is found, the last timezone in the list
  35     // with matching rules will be returned.
  36     if (entry->hasSameRules(timezone))
  37       known_timezone = entry;
  38   }
  39
  40   // May return NULL if we did not find a matching timezone in our list.
  41   return known_timezone;
  42 }
  43
  44 }  // namespace system
  45 }  // namespace chromeos