1 files changed, 239 insertions, 0 deletions
diff --git a/dom/system/gonk/TimeZoneSettingObserver.cpp b/dom/system/gonk/TimeZoneSettingObserver.cpp
new file mode 100644
index 000000000..512f79908
--- /dev/null
+++ b/dom/system/gonk/TimeZoneSettingObserver.cpp
@@ -0,0 +1,239 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "base/message_loop.h"
+#include "jsapi.h"
+#include "mozilla/dom/ScriptSettings.h"
+#include "mozilla/Attributes.h"
+#include "mozilla/ClearOnShutdown.h"
+#include "mozilla/Hal.h"
+#include "mozilla/Services.h"
+#include "mozilla/StaticPtr.h"
+#include "nsCOMPtr.h"
+#include "nsDebug.h"
+#include "nsIObserver.h"
+#include "nsIObserverService.h"
+#include "nsISettingsService.h"
+#include "nsJSUtils.h"
+#include "nsServiceManagerUtils.h"
+#include "nsString.h"
+#include "TimeZoneSettingObserver.h"
+#include "xpcpublic.h"
+#include "nsContentUtils.h"
+#include "nsPrintfCString.h"
+#include "mozilla/dom/BindingUtils.h"
+#include "mozilla/dom/SettingChangeNotificationBinding.h"
+
+#undef LOG
+#undef ERR
+#define LOG(args...)  __android_log_print(ANDROID_LOG_INFO, "Time Zone Setting" , ## args)
+#define ERR(args...)  __android_log_print(ANDROID_LOG_ERROR, "Time Zone Setting" , ## args)
+
+#define TIME_TIMEZONE       "time.timezone"
+#define MOZSETTINGS_CHANGED "mozsettings-changed"
+
+using namespace mozilla;
+using namespace mozilla::dom;
+
+namespace {
+
+class TimeZoneSettingObserver : public nsIObserver
+{
+public:
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSIOBSERVER
+
+  TimeZoneSettingObserver();
+  static nsresult SetTimeZone(const JS::Value &aValue, JSContext *aContext);
+
+protected:
+  virtual ~TimeZoneSettingObserver();
+};
+
+class TimeZoneSettingCb final : public nsISettingsServiceCallback
+{
+public:
+  NS_DECL_ISUPPORTS
+
+  TimeZoneSettingCb() {}
+
+  NS_IMETHOD Handle(const nsAString &aName, JS::Handle<JS::Value> aResult) {
+
+    JSContext *cx = nsContentUtils::GetCurrentJSContext();
+    NS_ENSURE_TRUE(cx, NS_OK);
+
+    // If we don't have time.timezone value in the settings, we need
+    // to initialize the settings based on the current system timezone
+    // to make settings consistent with system. This usually happens
+    // at the very first boot. After that, settings must have a value.
+    if (aResult.isNull()) {
+      // Get the current system time zone offset. Note that we need to
+      // convert the value to a UTC representation in the format of
+      // "UTC{+,-}hh:mm", so that the Gaia end can know how to interpret.
+      // E.g., -480 is "UTC+08:00"; 630 is "UTC-10:30".
+      int32_t timeZoneOffset = hal::GetTimezoneOffset();
+      nsPrintfCString curTimeZone("UTC%+03d:%02d",
+                                  -timeZoneOffset / 60,
+                                  abs(timeZoneOffset) % 60);
+
+      // Convert it to a JS string.
+      NS_ConvertUTF8toUTF16 utf16Str(curTimeZone);
+
+      JS::Rooted<JSString*> jsStr(cx, JS_NewUCStringCopyN(cx,
+                                                          utf16Str.get(),
+                                                          utf16Str.Length()));
+      if (!jsStr) {
+        return NS_ERROR_OUT_OF_MEMORY;
+      }
+
+      // Set the settings based on the current system timezone.
+      nsCOMPtr<nsISettingsServiceLock> lock;
+      nsCOMPtr<nsISettingsService> settingsService =
+        do_GetService("@mozilla.org/settingsService;1");
+      if (!settingsService) {
+        ERR("Failed to get settingsLock service!");
+        return NS_OK;
+      }
+      settingsService->CreateLock(nullptr, getter_AddRefs(lock));
+      JS::Rooted<JS::Value> value(cx, JS::StringValue(jsStr));
+      lock->Set(TIME_TIMEZONE, value, nullptr, nullptr);
+      return NS_OK;
+    }
+
+    // Set the system timezone based on the current settings.
+    if (aResult.isString()) {
+      return TimeZoneSettingObserver::SetTimeZone(aResult, cx);
+    }
+
+    return NS_OK;
+  }
+
+  NS_IMETHOD HandleError(const nsAString &aName) {
+    ERR("TimeZoneSettingCb::HandleError: %s\n", NS_LossyConvertUTF16toASCII(aName).get());
+    return NS_OK;
+  }
+
+protected:
+  ~TimeZoneSettingCb() {}
+};
+
+NS_IMPL_ISUPPORTS(TimeZoneSettingCb, nsISettingsServiceCallback)
+
+TimeZoneSettingObserver::TimeZoneSettingObserver()
+{
+  // Setup an observer to watch changes to the setting.
+  nsCOMPtr<nsIObserverService> observerService = services::GetObserverService();
+  if (!observerService) {
+    ERR("GetObserverService failed");
+    return;
+  }
+  nsresult rv;
+  rv = observerService->AddObserver(this, MOZSETTINGS_CHANGED, false);
+  if (NS_FAILED(rv)) {
+    ERR("AddObserver failed");
+    return;
+  }
+
+  // Read the 'time.timezone' setting in order to start with a known
+  // value at boot time. The handle() will be called after reading.
+  nsCOMPtr<nsISettingsServiceLock> lock;
+  nsCOMPtr<nsISettingsService> settingsService =
+    do_GetService("@mozilla.org/settingsService;1");
+  if (!settingsService) {
+    ERR("Failed to get settingsLock service!");
+    return;
+  }
+  settingsService->CreateLock(nullptr, getter_AddRefs(lock));
+  nsCOMPtr<nsISettingsServiceCallback> callback = new TimeZoneSettingCb();
+  lock->Get(TIME_TIMEZONE, callback);
+}
+
+nsresult TimeZoneSettingObserver::SetTimeZone(const JS::Value &aValue, JSContext *aContext)
+{
+  // Convert the JS value to a nsCString type.
+  // The value should be a JS string like "America/Chicago" or "UTC-05:00".
+  nsAutoJSString valueStr;
+  if (!valueStr.init(aContext, aValue.toString())) {
+    ERR("Failed to convert JS value to nsCString");
+    return NS_ERROR_FAILURE;
+  }
+  NS_ConvertUTF16toUTF8 newTimezone(valueStr);
+
+  // Hal expects opposite sign from general notations,
+  // so we need to flip it.
+  if (newTimezone.Find(NS_LITERAL_CSTRING("UTC+")) == 0) {
+    if (!newTimezone.SetCharAt('-', 3)) {
+      return NS_ERROR_FAILURE;
+    }
+  } else if (newTimezone.Find(NS_LITERAL_CSTRING("UTC-")) == 0) {
+    if (!newTimezone.SetCharAt('+', 3)) {
+      return NS_ERROR_FAILURE;
+    }
+  }
+
+  // Set the timezone only when the system timezone is not identical.
+  nsCString curTimezone = hal::GetTimezone();
+  if (!curTimezone.Equals(newTimezone)) {
+    hal::SetTimezone(newTimezone);
+  }
+
+  return NS_OK;
+}
+
+TimeZoneSettingObserver::~TimeZoneSettingObserver()
+{
+  nsCOMPtr<nsIObserverService> observerService = services::GetObserverService();
+  if (observerService) {
+    observerService->RemoveObserver(this, MOZSETTINGS_CHANGED);
+  }
+}
+
+NS_IMPL_ISUPPORTS(TimeZoneSettingObserver, nsIObserver)
+
+NS_IMETHODIMP
+TimeZoneSettingObserver::Observe(nsISupports *aSubject,
+                                 const char *aTopic,
+                                 const char16_t *aData)
+{
+  if (strcmp(aTopic, MOZSETTINGS_CHANGED) != 0) {
+    return NS_OK;
+  }
+
+  // Note that this function gets called for any and all settings changes,
+  // so we need to carefully check if we have the one we're interested in.
+  //
+  // The string that we're interested in will be a JSON string that looks like:
+  // {"key":"time.timezone","value":"America/Chicago"} or
+  // {"key":"time.timezone","value":"UTC-05:00"}
+
+  AutoSafeJSContext cx;
+  RootedDictionary<SettingChangeNotification> setting(cx);
+  if (!WrappedJSToDictionary(cx, aSubject, setting)) {
+    return NS_OK;
+  }
+  if (!setting.mKey.EqualsASCII(TIME_TIMEZONE)) {
+    return NS_OK;
+  }
+  if (!setting.mValue.isString()) {
+    return NS_OK;
+  }
+
+  // Set the system timezone.
+  return SetTimeZone(setting.mValue, cx);
+}
+
+} // namespace
+
+static mozilla::StaticRefPtr<TimeZoneSettingObserver> sTimeZoneSettingObserver;
+namespace mozilla {
+namespace system {
+void
+InitializeTimeZoneSettingObserver()
+{
+  sTimeZoneSettingObserver = new TimeZoneSettingObserver();
+  ClearOnShutdown(&sTimeZoneSettingObserver);
+}
+
+} // namespace system
+} // namespace mozilla