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 "chromeos/settings/timezone_settings.h"
6
7 #include <string>
8
9 #include "base/bind.h"
10 #include "base/file_util.h"
11 #include "base/files/file_path.h"
12 #include "base/location.h"
13 #include "base/logging.h"
14 #include "base/memory/scoped_ptr.h"
15 #include "base/memory/singleton.h"
16 #include "base/observer_list.h"
17 #include "base/stl_util.h"
18 #include "base/strings/string_util.h"
19 #include "base/strings/utf_string_conversions.h"
20 #include "base/sys_info.h"
21 #include "base/task_runner.h"
22 #include "base/threading/worker_pool.h"
23 #include "third_party/icu/source/i18n/unicode/timezone.h"
24
25 namespace {
26
27 // The filepath to the timezone file that symlinks to the actual timezone file.
28 const char kTimezoneSymlink[] = "/var/lib/timezone/localtime";
29 const char kTimezoneSymlink2[] = "/var/lib/timezone/localtime2";
30
31 // The directory that contains all the timezone files. So for timezone
32 // "US/Pacific", the actual timezone file is: "/usr/share/zoneinfo/US/Pacific"
33 const char kTimezoneFilesDir[] = "/usr/share/zoneinfo/";
34
35 // Fallback time zone ID used in case of an unexpected error.
36 const char kFallbackTimeZoneId[] = "America/Los_Angeles";
37
38 // TODO(jungshik): Using Enumerate method in ICU gives 600+ timezones.
39 // Even after filtering out duplicate entries with a strict identity check,
40 // we still have 400+ zones. Relaxing the criteria for the timezone
41 // identity is likely to cut down the number to < 100. Until we
42 // come up with a better list, we hard-code the following list. It came from
43 // from Android initially, but more entries have been added.
44 static const char* kTimeZones[] = {
45 "Pacific/Midway",
46 "Pacific/Honolulu",
47 "America/Anchorage",
48 "America/Los_Angeles",
49 "America/Vancouver",
50 "America/Tijuana",
51 "America/Phoenix",
52 "America/Chihuahua",
53 "America/Denver",
54 "America/Edmonton",
55 "America/Mazatlan",
56 "America/Regina",
57 "America/Costa_Rica",
58 "America/Chicago",
59 "America/Mexico_City",
60 "America/Winnipeg",
61 "Pacific/Easter",
62 "America/Bogota",
63 "America/Lima",
64 "America/New_York",
65 "America/Toronto",
66 "America/Caracas",
67 "America/Barbados",
68 "America/Halifax",
69 "America/Manaus",
70 "America/Santiago",
71 "America/St_Johns",
72 "America/Araguaina",
73 "America/Argentina/Buenos_Aires",
74 "America/Argentina/San_Luis",
75 "America/Sao_Paulo",
76 "America/Montevideo",
77 "America/Godthab",
78 "Atlantic/South_Georgia",
79 "Atlantic/Cape_Verde",
80 "Atlantic/Azores",
81 "Atlantic/Reykjavik",
82 "Atlantic/St_Helena",
83 "Africa/Casablanca",
84 "Atlantic/Faroe",
85 "Europe/Dublin",
86 "Europe/Lisbon",
87 "Europe/London",
88 "Europe/Amsterdam",
89 "Europe/Belgrade",
90 "Europe/Berlin",
91 "Europe/Brussels",
92 "Europe/Budapest",
93 "Europe/Copenhagen",
94 "Europe/Ljubljana",
95 "Europe/Madrid",
96 "Europe/Oslo",
97 "Europe/Paris",
98 "Europe/Prague",
99 "Europe/Rome",
100 "Europe/Stockholm",
101 "Europe/Sarajevo",
102 "Europe/Tirane",
103 "Europe/Vienna",
104 "Europe/Warsaw",
105 "Europe/Zurich",
106 "Africa/Windhoek",
107 "Africa/Lagos",
108 "Africa/Brazzaville",
109 "Africa/Cairo",
110 "Africa/Harare",
111 "Africa/Maputo",
112 "Africa/Johannesburg",
113 "Europe/Athens",
114 "Europe/Bucharest",
115 "Europe/Chisinau",
116 "Europe/Helsinki",
117 "Europe/Istanbul",
118 "Europe/Kiev",
119 "Europe/Riga",
120 "Europe/Sofia",
121 "Europe/Tallinn",
122 "Europe/Vilnius",
123 "Asia/Amman",
124 "Asia/Beirut",
125 "Asia/Jerusalem",
126 "Africa/Nairobi",
127 "Asia/Baghdad",
128 "Asia/Riyadh",
129 "Asia/Kuwait",
130 "Europe/Minsk",
131 "Asia/Tehran",
132 "Europe/Moscow",
133 "Asia/Dubai",
134 "Asia/Tbilisi",
135 "Indian/Mauritius",
136 "Asia/Baku",
137 "Asia/Yerevan",
138 "Asia/Kabul",
139 "Asia/Karachi",
140 "Asia/Ashgabat",
141 "Asia/Oral",
142 "Asia/Calcutta",
143 "Asia/Colombo",
144 "Asia/Katmandu",
145 "Asia/Yekaterinburg",
146 "Asia/Almaty",
147 "Asia/Dhaka",
148 "Asia/Rangoon",
149 "Asia/Bangkok",
150 "Asia/Jakarta",
151 "Asia/Omsk",
152 "Asia/Novosibirsk",
153 "Asia/Ho_Chi_Minh",
154 "Asia/Phnom_Penh",
155 "Asia/Vientiane",
156 "Asia/Shanghai",
157 "Asia/Hong_Kong",
158 "Asia/Kuala_Lumpur",
159 "Asia/Singapore",
160 "Asia/Manila",
161 "Asia/Taipei",
162 "Asia/Makassar",
163 "Asia/Krasnoyarsk",
164 "Australia/Perth",
165 "Australia/Eucla",
166 "Asia/Irkutsk",
167 "Asia/Seoul",
168 "Asia/Tokyo",
169 "Asia/Jayapura",
170 "Australia/Darwin",
171 "Australia/Adelaide",
172 "Asia/Yakutsk",
173 "Pacific/Guam",
174 "Australia/Brisbane",
175 "Australia/Hobart",
176 "Australia/Sydney",
177 "Pacific/Port_Moresby",
178 "Asia/Vladivostok",
179 "Asia/Sakhalin",
180 "Asia/Magadan",
181 "Pacific/Fiji",
182 "Pacific/Majuro",
183 "Pacific/Auckland",
184 "Pacific/Tongatapu",
185 "Pacific/Apia",
186 "Pacific/Kiritimati",
187 };
188
GetTimezoneIDAsString()189 std::string GetTimezoneIDAsString() {
190 // Compare with chromiumos/src/platform/init/ui.conf which fixes certain
191 // incorrect states of the timezone symlink on startup. Thus errors occuring
192 // here should be rather contrived.
193
194 // Look at kTimezoneSymlink, see which timezone we are symlinked to.
195 char buf[256];
196 const ssize_t len = readlink(kTimezoneSymlink, buf,
197 sizeof(buf)-1);
198 if (len == -1) {
199 LOG(ERROR) << "GetTimezoneID: Cannot read timezone symlink "
200 << kTimezoneSymlink;
201 return std::string();
202 }
203
204 std::string timezone(buf, len);
205 // Remove kTimezoneFilesDir from the beginning.
206 if (timezone.find(kTimezoneFilesDir) != 0) {
207 LOG(ERROR) << "GetTimezoneID: Timezone symlink is wrong "
208 << timezone;
209 return std::string();
210 }
211
212 return timezone.substr(strlen(kTimezoneFilesDir));
213 }
214
SetTimezoneIDFromString(const std::string & id)215 void SetTimezoneIDFromString(const std::string& id) {
216 // Change the kTimezoneSymlink symlink to the path for this timezone.
217 // We want to do this in an atomic way. So we are going to create the symlink
218 // at kTimezoneSymlink2 and then move it to kTimezoneSymlink
219
220 base::FilePath timezone_symlink(kTimezoneSymlink);
221 base::FilePath timezone_symlink2(kTimezoneSymlink2);
222 base::FilePath timezone_file(kTimezoneFilesDir + id);
223
224 // Make sure timezone_file exists.
225 if (!base::PathExists(timezone_file)) {
226 LOG(ERROR) << "SetTimezoneID: Cannot find timezone file "
227 << timezone_file.value();
228 return;
229 }
230
231 // Delete old symlink2 if it exists.
232 base::DeleteFile(timezone_symlink2, false);
233
234 // Create new symlink2.
235 if (symlink(timezone_file.value().c_str(),
236 timezone_symlink2.value().c_str()) == -1) {
237 LOG(ERROR) << "SetTimezoneID: Unable to create symlink "
238 << timezone_symlink2.value() << " to " << timezone_file.value();
239 return;
240 }
241
242 // Move symlink2 to symlink.
243 if (!base::ReplaceFile(timezone_symlink2, timezone_symlink, NULL)) {
244 LOG(ERROR) << "SetTimezoneID: Unable to move symlink "
245 << timezone_symlink2.value() << " to "
246 << timezone_symlink.value();
247 }
248 }
249
250 // Common code of the TimezoneSettings implementations.
251 class TimezoneSettingsBaseImpl : public chromeos::system::TimezoneSettings {
252 public:
253 virtual ~TimezoneSettingsBaseImpl();
254
255 // TimezoneSettings implementation:
256 virtual const icu::TimeZone& GetTimezone() OVERRIDE;
257 virtual string16 GetCurrentTimezoneID() OVERRIDE;
258 virtual void SetTimezoneFromID(const string16& timezone_id) OVERRIDE;
259 virtual void AddObserver(Observer* observer) OVERRIDE;
260 virtual void RemoveObserver(Observer* observer) OVERRIDE;
261 virtual const std::vector<icu::TimeZone*>& GetTimezoneList() const OVERRIDE;
262
263 protected:
264 TimezoneSettingsBaseImpl();
265
266 // Returns |timezone| if it is an element of |timezones_|.
267 // Otherwise, returns a timezone from |timezones_|, if such exists, that has
268 // the same rule as the given |timezone|.
269 // Otherwise, returns NULL.
270 // Note multiple timezones with the same time zone offset may exist
271 // e.g.
272 // US/Pacific == America/Los_Angeles
273 const icu::TimeZone* GetKnownTimezoneOrNull(
274 const icu::TimeZone& timezone) const;
275
276 ObserverList<Observer> observers_;
277 std::vector<icu::TimeZone*> timezones_;
278 scoped_ptr<icu::TimeZone> timezone_;
279
280 private:
281 DISALLOW_COPY_AND_ASSIGN(TimezoneSettingsBaseImpl);
282 };
283
284 // The TimezoneSettings implementation used in production.
285 class TimezoneSettingsImpl : public TimezoneSettingsBaseImpl {
286 public:
287 // TimezoneSettings implementation:
288 virtual void SetTimezone(const icu::TimeZone& timezone) OVERRIDE;
289
290 static TimezoneSettingsImpl* GetInstance();
291
292 private:
293 friend struct DefaultSingletonTraits<TimezoneSettingsImpl>;
294
295 TimezoneSettingsImpl();
296
297 DISALLOW_COPY_AND_ASSIGN(TimezoneSettingsImpl);
298 };
299
300 // The stub TimezoneSettings implementation used on Linux desktop.
301 class TimezoneSettingsStubImpl : public TimezoneSettingsBaseImpl {
302 public:
303 // TimezoneSettings implementation:
304 virtual void SetTimezone(const icu::TimeZone& timezone) OVERRIDE;
305
306 static TimezoneSettingsStubImpl* GetInstance();
307
308 private:
309 friend struct DefaultSingletonTraits<TimezoneSettingsStubImpl>;
310
311 TimezoneSettingsStubImpl();
312
313 DISALLOW_COPY_AND_ASSIGN(TimezoneSettingsStubImpl);
314 };
315
~TimezoneSettingsBaseImpl()316 TimezoneSettingsBaseImpl::~TimezoneSettingsBaseImpl() {
317 STLDeleteElements(&timezones_);
318 }
319
GetTimezone()320 const icu::TimeZone& TimezoneSettingsBaseImpl::GetTimezone() {
321 return *timezone_.get();
322 }
323
GetCurrentTimezoneID()324 string16 TimezoneSettingsBaseImpl::GetCurrentTimezoneID() {
325 return chromeos::system::TimezoneSettings::GetTimezoneID(GetTimezone());
326 }
327
SetTimezoneFromID(const string16 & timezone_id)328 void TimezoneSettingsBaseImpl::SetTimezoneFromID(const string16& timezone_id) {
329 scoped_ptr<icu::TimeZone> timezone(icu::TimeZone::createTimeZone(
330 icu::UnicodeString(timezone_id.c_str(), timezone_id.size())));
331 SetTimezone(*timezone);
332 }
333
AddObserver(Observer * observer)334 void TimezoneSettingsBaseImpl::AddObserver(Observer* observer) {
335 observers_.AddObserver(observer);
336 }
337
RemoveObserver(Observer * observer)338 void TimezoneSettingsBaseImpl::RemoveObserver(Observer* observer) {
339 observers_.RemoveObserver(observer);
340 }
341
342 const std::vector<icu::TimeZone*>&
GetTimezoneList() const343 TimezoneSettingsBaseImpl::GetTimezoneList() const {
344 return timezones_;
345 }
346
TimezoneSettingsBaseImpl()347 TimezoneSettingsBaseImpl::TimezoneSettingsBaseImpl() {
348 for (size_t i = 0; i < arraysize(kTimeZones); ++i) {
349 timezones_.push_back(icu::TimeZone::createTimeZone(
350 icu::UnicodeString(kTimeZones[i], -1, US_INV)));
351 }
352 }
353
GetKnownTimezoneOrNull(const icu::TimeZone & timezone) const354 const icu::TimeZone* TimezoneSettingsBaseImpl::GetKnownTimezoneOrNull(
355 const icu::TimeZone& timezone) const {
356 const icu::TimeZone* known_timezone = NULL;
357 for (std::vector<icu::TimeZone*>::const_iterator iter = timezones_.begin();
358 iter != timezones_.end(); ++iter) {
359 const icu::TimeZone* entry = *iter;
360 if (*entry == timezone)
361 return entry;
362 if (entry->hasSameRules(timezone))
363 known_timezone = entry;
364 }
365
366 // May return NULL if we did not find a matching timezone in our list.
367 return known_timezone;
368 }
369
SetTimezone(const icu::TimeZone & timezone)370 void TimezoneSettingsImpl::SetTimezone(const icu::TimeZone& timezone) {
371 // Replace |timezone| by a known timezone with the same rules. If none exists
372 // go on with |timezone|.
373 const icu::TimeZone* known_timezone = GetKnownTimezoneOrNull(timezone);
374 if (!known_timezone)
375 known_timezone = &timezone;
376
377 timezone_.reset(known_timezone->clone());
378 std::string id = UTF16ToUTF8(GetTimezoneID(*known_timezone));
379 VLOG(1) << "Setting timezone to " << id;
380 // It's safe to change the timezone config files in the background as the
381 // following operations don't depend on the completion of the config change.
382 base::WorkerPool::GetTaskRunner(true /* task is slow */)->
383 PostTask(FROM_HERE, base::Bind(&SetTimezoneIDFromString, id));
384 icu::TimeZone::setDefault(*known_timezone);
385 FOR_EACH_OBSERVER(Observer, observers_, TimezoneChanged(*known_timezone));
386 }
387
388 // static
GetInstance()389 TimezoneSettingsImpl* TimezoneSettingsImpl::GetInstance() {
390 return Singleton<TimezoneSettingsImpl,
391 DefaultSingletonTraits<TimezoneSettingsImpl> >::get();
392 }
393
TimezoneSettingsImpl()394 TimezoneSettingsImpl::TimezoneSettingsImpl() {
395 std::string id = GetTimezoneIDAsString();
396 if (id.empty()) {
397 id = kFallbackTimeZoneId;
398 LOG(ERROR) << "Got an empty string for timezone, default to '" << id;
399 }
400
401 timezone_.reset(icu::TimeZone::createTimeZone(
402 icu::UnicodeString::fromUTF8(id)));
403
404 // Store a known timezone equivalent to id in |timezone_|.
405 const icu::TimeZone* known_timezone = GetKnownTimezoneOrNull(*timezone_);
406 if (known_timezone != NULL && *known_timezone != *timezone_)
407 // Not necessary to update the filesystem because |known_timezone| has the
408 // same rules.
409 timezone_.reset(known_timezone->clone());
410
411 icu::TimeZone::setDefault(*timezone_);
412 VLOG(1) << "Timezone initially set to " << id;
413 }
414
SetTimezone(const icu::TimeZone & timezone)415 void TimezoneSettingsStubImpl::SetTimezone(const icu::TimeZone& timezone) {
416 // Replace |timezone| by a known timezone with the same rules. If none exists
417 // go on with |timezone|.
418 const icu::TimeZone* known_timezone = GetKnownTimezoneOrNull(timezone);
419 if (!known_timezone)
420 known_timezone = &timezone;
421
422 timezone_.reset(known_timezone->clone());
423 icu::TimeZone::setDefault(*known_timezone);
424 FOR_EACH_OBSERVER(Observer, observers_, TimezoneChanged(*known_timezone));
425 }
426
427 // static
GetInstance()428 TimezoneSettingsStubImpl* TimezoneSettingsStubImpl::GetInstance() {
429 return Singleton<TimezoneSettingsStubImpl,
430 DefaultSingletonTraits<TimezoneSettingsStubImpl> >::get();
431 }
432
TimezoneSettingsStubImpl()433 TimezoneSettingsStubImpl::TimezoneSettingsStubImpl() {
434 timezone_.reset(icu::TimeZone::createDefault());
435 const icu::TimeZone* known_timezone = GetKnownTimezoneOrNull(*timezone_);
436 if (known_timezone != NULL && *known_timezone != *timezone_)
437 timezone_.reset(known_timezone->clone());
438 }
439
440 } // namespace
441
442 namespace chromeos {
443 namespace system {
444
~Observer()445 TimezoneSettings::Observer::~Observer() {}
446
447 // static
GetInstance()448 TimezoneSettings* TimezoneSettings::GetInstance() {
449 if (base::SysInfo::IsRunningOnChromeOS()) {
450 return TimezoneSettingsImpl::GetInstance();
451 } else {
452 return TimezoneSettingsStubImpl::GetInstance();
453 }
454 }
455
456 // static
GetTimezoneID(const icu::TimeZone & timezone)457 string16 TimezoneSettings::GetTimezoneID(const icu::TimeZone& timezone) {
458 icu::UnicodeString id;
459 timezone.getID(id);
460 return string16(id.getBuffer(), id.length());
461 }
462
463 } // namespace system
464 } // namespace chromeos
465