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/files/file_path.h"
11 #include "base/files/file_util.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/Kaliningrad",
114 "Europe/Athens",
115 "Europe/Bucharest",
116 "Europe/Chisinau",
117 "Europe/Helsinki",
118 "Europe/Istanbul",
119 "Europe/Kiev",
120 "Europe/Riga",
121 "Europe/Sofia",
122 "Europe/Tallinn",
123 "Europe/Vilnius",
124 "Asia/Amman",
125 "Asia/Beirut",
126 "Asia/Jerusalem",
127 "Africa/Nairobi",
128 "Asia/Baghdad",
129 "Asia/Riyadh",
130 "Asia/Kuwait",
131 "Europe/Minsk",
132 "Europe/Moscow",
133 "Asia/Tehran",
134 "Europe/Samara",
135 "Asia/Dubai",
136 "Asia/Tbilisi",
137 "Indian/Mauritius",
138 "Asia/Baku",
139 "Asia/Yerevan",
140 "Asia/Kabul",
141 "Asia/Karachi",
142 "Asia/Ashgabat",
143 "Asia/Oral",
144 "Asia/Yekaterinburg",
145 "Asia/Calcutta",
146 "Asia/Colombo",
147 "Asia/Katmandu",
148 "Asia/Omsk",
149 "Asia/Almaty",
150 "Asia/Dhaka",
151 "Asia/Novosibirsk",
152 "Asia/Rangoon",
153 "Asia/Bangkok",
154 "Asia/Jakarta",
155 "Asia/Krasnoyarsk",
156 "Asia/Novokuznetsk",
157 "Asia/Ho_Chi_Minh",
158 "Asia/Phnom_Penh",
159 "Asia/Vientiane",
160 "Asia/Shanghai",
161 "Asia/Hong_Kong",
162 "Asia/Kuala_Lumpur",
163 "Asia/Singapore",
164 "Asia/Manila",
165 "Asia/Taipei",
166 "Asia/Makassar",
167 "Asia/Irkutsk",
168 "Asia/Yakutsk",
169 "Australia/Perth",
170 "Australia/Eucla",
171 "Asia/Seoul",
172 "Asia/Tokyo",
173 "Asia/Jayapura",
174 "Asia/Sakhalin",
175 "Asia/Vladivostok",
176 "Asia/Magadan",
177 "Australia/Darwin",
178 "Australia/Adelaide",
179 "Pacific/Guam",
180 "Australia/Brisbane",
181 "Australia/Hobart",
182 "Australia/Sydney",
183 "Asia/Anadyr",
184 "Pacific/Port_Moresby",
185 "Asia/Kamchatka",
186 "Pacific/Fiji",
187 "Pacific/Majuro",
188 "Pacific/Auckland",
189 "Pacific/Tongatapu",
190 "Pacific/Apia",
191 "Pacific/Kiritimati",
192 };
193
GetTimezoneIDAsString()194 std::string GetTimezoneIDAsString() {
195 // Compare with chromiumos/src/platform/init/ui.conf which fixes certain
196 // incorrect states of the timezone symlink on startup. Thus errors occuring
197 // here should be rather contrived.
198
199 // Look at kTimezoneSymlink, see which timezone we are symlinked to.
200 char buf[256];
201 const ssize_t len = readlink(kTimezoneSymlink, buf,
202 sizeof(buf)-1);
203 if (len == -1) {
204 LOG(ERROR) << "GetTimezoneID: Cannot read timezone symlink "
205 << kTimezoneSymlink;
206 return std::string();
207 }
208
209 std::string timezone(buf, len);
210 // Remove kTimezoneFilesDir from the beginning.
211 if (timezone.find(kTimezoneFilesDir) != 0) {
212 LOG(ERROR) << "GetTimezoneID: Timezone symlink is wrong "
213 << timezone;
214 return std::string();
215 }
216
217 return timezone.substr(strlen(kTimezoneFilesDir));
218 }
219
SetTimezoneIDFromString(const std::string & id)220 void SetTimezoneIDFromString(const std::string& id) {
221 // Change the kTimezoneSymlink symlink to the path for this timezone.
222 // We want to do this in an atomic way. So we are going to create the symlink
223 // at kTimezoneSymlink2 and then move it to kTimezoneSymlink
224
225 base::FilePath timezone_symlink(kTimezoneSymlink);
226 base::FilePath timezone_symlink2(kTimezoneSymlink2);
227 base::FilePath timezone_file(kTimezoneFilesDir + id);
228
229 // Make sure timezone_file exists.
230 if (!base::PathExists(timezone_file)) {
231 LOG(ERROR) << "SetTimezoneID: Cannot find timezone file "
232 << timezone_file.value();
233 return;
234 }
235
236 // Delete old symlink2 if it exists.
237 base::DeleteFile(timezone_symlink2, false);
238
239 // Create new symlink2.
240 if (symlink(timezone_file.value().c_str(),
241 timezone_symlink2.value().c_str()) == -1) {
242 LOG(ERROR) << "SetTimezoneID: Unable to create symlink "
243 << timezone_symlink2.value() << " to " << timezone_file.value();
244 return;
245 }
246
247 // Move symlink2 to symlink.
248 if (!base::ReplaceFile(timezone_symlink2, timezone_symlink, NULL)) {
249 LOG(ERROR) << "SetTimezoneID: Unable to move symlink "
250 << timezone_symlink2.value() << " to "
251 << timezone_symlink.value();
252 }
253 }
254
255 // Common code of the TimezoneSettings implementations.
256 class TimezoneSettingsBaseImpl : public chromeos::system::TimezoneSettings {
257 public:
258 virtual ~TimezoneSettingsBaseImpl();
259
260 // TimezoneSettings implementation:
261 virtual const icu::TimeZone& GetTimezone() OVERRIDE;
262 virtual base::string16 GetCurrentTimezoneID() OVERRIDE;
263 virtual void SetTimezoneFromID(const base::string16& timezone_id) OVERRIDE;
264 virtual void AddObserver(Observer* observer) OVERRIDE;
265 virtual void RemoveObserver(Observer* observer) OVERRIDE;
266 virtual const std::vector<icu::TimeZone*>& GetTimezoneList() const OVERRIDE;
267
268 protected:
269 TimezoneSettingsBaseImpl();
270
271 // Returns |timezone| if it is an element of |timezones_|.
272 // Otherwise, returns a timezone from |timezones_|, if such exists, that has
273 // the same rule as the given |timezone|.
274 // Otherwise, returns NULL.
275 // Note multiple timezones with the same time zone offset may exist
276 // e.g.
277 // US/Pacific == America/Los_Angeles
278 const icu::TimeZone* GetKnownTimezoneOrNull(
279 const icu::TimeZone& timezone) const;
280
281 ObserverList<Observer> observers_;
282 std::vector<icu::TimeZone*> timezones_;
283 scoped_ptr<icu::TimeZone> timezone_;
284
285 private:
286 DISALLOW_COPY_AND_ASSIGN(TimezoneSettingsBaseImpl);
287 };
288
289 // The TimezoneSettings implementation used in production.
290 class TimezoneSettingsImpl : public TimezoneSettingsBaseImpl {
291 public:
292 // TimezoneSettings implementation:
293 virtual void SetTimezone(const icu::TimeZone& timezone) OVERRIDE;
294
295 static TimezoneSettingsImpl* GetInstance();
296
297 private:
298 friend struct DefaultSingletonTraits<TimezoneSettingsImpl>;
299
300 TimezoneSettingsImpl();
301
302 DISALLOW_COPY_AND_ASSIGN(TimezoneSettingsImpl);
303 };
304
305 // The stub TimezoneSettings implementation used on Linux desktop.
306 class TimezoneSettingsStubImpl : public TimezoneSettingsBaseImpl {
307 public:
308 // TimezoneSettings implementation:
309 virtual void SetTimezone(const icu::TimeZone& timezone) OVERRIDE;
310
311 static TimezoneSettingsStubImpl* GetInstance();
312
313 private:
314 friend struct DefaultSingletonTraits<TimezoneSettingsStubImpl>;
315
316 TimezoneSettingsStubImpl();
317
318 DISALLOW_COPY_AND_ASSIGN(TimezoneSettingsStubImpl);
319 };
320
~TimezoneSettingsBaseImpl()321 TimezoneSettingsBaseImpl::~TimezoneSettingsBaseImpl() {
322 STLDeleteElements(&timezones_);
323 }
324
GetTimezone()325 const icu::TimeZone& TimezoneSettingsBaseImpl::GetTimezone() {
326 return *timezone_.get();
327 }
328
GetCurrentTimezoneID()329 base::string16 TimezoneSettingsBaseImpl::GetCurrentTimezoneID() {
330 return chromeos::system::TimezoneSettings::GetTimezoneID(GetTimezone());
331 }
332
SetTimezoneFromID(const base::string16 & timezone_id)333 void TimezoneSettingsBaseImpl::SetTimezoneFromID(
334 const base::string16& timezone_id) {
335 scoped_ptr<icu::TimeZone> timezone(icu::TimeZone::createTimeZone(
336 icu::UnicodeString(timezone_id.c_str(), timezone_id.size())));
337 SetTimezone(*timezone);
338 }
339
AddObserver(Observer * observer)340 void TimezoneSettingsBaseImpl::AddObserver(Observer* observer) {
341 observers_.AddObserver(observer);
342 }
343
RemoveObserver(Observer * observer)344 void TimezoneSettingsBaseImpl::RemoveObserver(Observer* observer) {
345 observers_.RemoveObserver(observer);
346 }
347
348 const std::vector<icu::TimeZone*>&
GetTimezoneList() const349 TimezoneSettingsBaseImpl::GetTimezoneList() const {
350 return timezones_;
351 }
352
TimezoneSettingsBaseImpl()353 TimezoneSettingsBaseImpl::TimezoneSettingsBaseImpl() {
354 for (size_t i = 0; i < arraysize(kTimeZones); ++i) {
355 timezones_.push_back(icu::TimeZone::createTimeZone(
356 icu::UnicodeString(kTimeZones[i], -1, US_INV)));
357 }
358 }
359
GetKnownTimezoneOrNull(const icu::TimeZone & timezone) const360 const icu::TimeZone* TimezoneSettingsBaseImpl::GetKnownTimezoneOrNull(
361 const icu::TimeZone& timezone) const {
362 const icu::TimeZone* known_timezone = NULL;
363 for (std::vector<icu::TimeZone*>::const_iterator iter = timezones_.begin();
364 iter != timezones_.end(); ++iter) {
365 const icu::TimeZone* entry = *iter;
366 if (*entry == timezone)
367 return entry;
368 if (entry->hasSameRules(timezone))
369 known_timezone = entry;
370 }
371
372 // May return NULL if we did not find a matching timezone in our list.
373 return known_timezone;
374 }
375
SetTimezone(const icu::TimeZone & timezone)376 void TimezoneSettingsImpl::SetTimezone(const icu::TimeZone& timezone) {
377 // Replace |timezone| by a known timezone with the same rules. If none exists
378 // go on with |timezone|.
379 const icu::TimeZone* known_timezone = GetKnownTimezoneOrNull(timezone);
380 if (!known_timezone)
381 known_timezone = &timezone;
382
383 timezone_.reset(known_timezone->clone());
384 std::string id = base::UTF16ToUTF8(GetTimezoneID(*known_timezone));
385 VLOG(1) << "Setting timezone to " << id;
386 // It's safe to change the timezone config files in the background as the
387 // following operations don't depend on the completion of the config change.
388 base::WorkerPool::GetTaskRunner(true /* task is slow */)->
389 PostTask(FROM_HERE, base::Bind(&SetTimezoneIDFromString, id));
390 icu::TimeZone::setDefault(*known_timezone);
391 FOR_EACH_OBSERVER(Observer, observers_, TimezoneChanged(*known_timezone));
392 }
393
394 // static
GetInstance()395 TimezoneSettingsImpl* TimezoneSettingsImpl::GetInstance() {
396 return Singleton<TimezoneSettingsImpl,
397 DefaultSingletonTraits<TimezoneSettingsImpl> >::get();
398 }
399
TimezoneSettingsImpl()400 TimezoneSettingsImpl::TimezoneSettingsImpl() {
401 std::string id = GetTimezoneIDAsString();
402 if (id.empty()) {
403 id = kFallbackTimeZoneId;
404 LOG(ERROR) << "Got an empty string for timezone, default to '" << id;
405 }
406
407 timezone_.reset(icu::TimeZone::createTimeZone(
408 icu::UnicodeString::fromUTF8(id)));
409
410 // Store a known timezone equivalent to id in |timezone_|.
411 const icu::TimeZone* known_timezone = GetKnownTimezoneOrNull(*timezone_);
412 if (known_timezone != NULL && *known_timezone != *timezone_)
413 // Not necessary to update the filesystem because |known_timezone| has the
414 // same rules.
415 timezone_.reset(known_timezone->clone());
416
417 icu::TimeZone::setDefault(*timezone_);
418 VLOG(1) << "Timezone initially set to " << id;
419 }
420
SetTimezone(const icu::TimeZone & timezone)421 void TimezoneSettingsStubImpl::SetTimezone(const icu::TimeZone& timezone) {
422 // Replace |timezone| by a known timezone with the same rules. If none exists
423 // go on with |timezone|.
424 const icu::TimeZone* known_timezone = GetKnownTimezoneOrNull(timezone);
425 if (!known_timezone)
426 known_timezone = &timezone;
427
428 timezone_.reset(known_timezone->clone());
429 icu::TimeZone::setDefault(*known_timezone);
430 FOR_EACH_OBSERVER(Observer, observers_, TimezoneChanged(*known_timezone));
431 }
432
433 // static
GetInstance()434 TimezoneSettingsStubImpl* TimezoneSettingsStubImpl::GetInstance() {
435 return Singleton<TimezoneSettingsStubImpl,
436 DefaultSingletonTraits<TimezoneSettingsStubImpl> >::get();
437 }
438
TimezoneSettingsStubImpl()439 TimezoneSettingsStubImpl::TimezoneSettingsStubImpl() {
440 timezone_.reset(icu::TimeZone::createDefault());
441 const icu::TimeZone* known_timezone = GetKnownTimezoneOrNull(*timezone_);
442 if (known_timezone != NULL && *known_timezone != *timezone_)
443 timezone_.reset(known_timezone->clone());
444 }
445
446 } // namespace
447
448 namespace chromeos {
449 namespace system {
450
~Observer()451 TimezoneSettings::Observer::~Observer() {}
452
453 // static
GetInstance()454 TimezoneSettings* TimezoneSettings::GetInstance() {
455 if (base::SysInfo::IsRunningOnChromeOS()) {
456 return TimezoneSettingsImpl::GetInstance();
457 } else {
458 return TimezoneSettingsStubImpl::GetInstance();
459 }
460 }
461
462 // static
GetTimezoneID(const icu::TimeZone & timezone)463 base::string16 TimezoneSettings::GetTimezoneID(const icu::TimeZone& timezone) {
464 icu::UnicodeString id;
465 timezone.getID(id);
466 return base::string16(id.getBuffer(), id.length());
467 }
468
469 } // namespace system
470 } // namespace chromeos
471