Adding upstream version 124.0.1.upstream/124.0.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 185 insertions, 0 deletions

diff --git a/intl/locale/OSPreferences.h b/intl/locale/OSPreferences.h
new file mode 100644
index 0000000000..e8d95f823b
--- /dev/null
+++ b/intl/locale/OSPreferences.h
@@ -0,0 +1,185 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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/. */
+
+#ifndef mozilla_intl_IntlOSPreferences_h__
+#define mozilla_intl_IntlOSPreferences_h__
+
+#include "mozilla/StaticPtr.h"
+#include "nsTHashMap.h"
+#include "nsString.h"
+#include "nsTArray.h"
+
+#include "mozIOSPreferences.h"
+
+namespace mozilla {
+namespace intl {
+
+/**
+ * OSPreferences API provides a set of methods for retrieving information from
+ * the host environment on topics such as:
+ *   - Internationalization
+ *   - Localization
+ *   - Regional preferences
+ *
+ * The API is meant to remain as simple as possible, relaying information from
+ * the host environment to the user without too much logic.
+ *
+ * Saying that, there are two exceptions to that paradigm.
+ *
+ * First one is normalization. We do intend to translate host environment
+ * concepts to unified Intl/L10n vocabulary used by Mozilla.
+ * That means that we will format locale IDs, timezone names, currencies etc.
+ * into a chosen format.
+ *
+ * Second is caching. This API does cache values and where possible will
+ * hook into the environment for some event-driven cache invalidation.
+ *
+ * This means that on platforms that do not support a mechanism to
+ * notify apps about changes, new OS-level settings may not be reflected
+ * in the app until it is relaunched.
+ */
+class OSPreferences : public mozIOSPreferences {
+ public:
+  NS_DECL_THREADSAFE_ISUPPORTS
+  NS_DECL_MOZIOSPREFERENCES
+
+  enum class DateTimeFormatStyle {
+    Invalid = -1,
+    None,
+    Short,   // e.g. time: HH:mm, date: Y/m/d
+    Medium,  // likely same as Short
+    Long,    // e.g. time: including seconds, date: including weekday
+    Full     // e.g. time: with timezone, date: with long weekday, month
+  };
+
+  /**
+   * Constructor, to do any necessary initialization such as registering for
+   * notifications from the system when prefs are modified.
+   */
+  OSPreferences();
+
+  /**
+   * Create (if necessary) and return a raw pointer to the singleton instance.
+   * Use this accessor in C++ code that just wants to call a method on the
+   * instance, but does not need to hold a reference, as in
+   *    nsAutoCString str;
+   *    OSPreferences::GetInstance()->GetSystemLocale(str);
+   *
+   * NOTE that this is not safe for off-main-thread use, because it is possible
+   * that XPCOM shutdown on the main thread could invalidate it at any moment!
+   */
+  static OSPreferences* GetInstance();
+
+  /**
+   * Return an addRef'd pointer to the singleton instance. This is used by the
+   * XPCOM constructor that exists to support usage from JS.
+   */
+  static already_AddRefed<OSPreferences> GetInstanceAddRefed();
+
+  static bool GetPatternForSkeleton(const nsACString& aSkeleton,
+                                    const nsACString& aLocale,
+                                    nsACString& aRetVal);
+
+  static bool GetDateTimeConnectorPattern(const nsACString& aLocale,
+                                          nsACString& aRetVal);
+
+  /**
+   * Triggers a refresh of retrieving data from host environment.
+   *
+   * If the result differs from the previous list, it will additionally
+   * trigger global events for changed values:
+   *
+   *  * SystemLocales: "intl:system-locales-changed"
+   *
+   * This method should not be called from anywhere except of per-platform
+   * hooks into OS events.
+   */
+  void Refresh();
+
+ protected:
+  nsTArray<nsCString> mSystemLocales;
+  nsTArray<nsCString> mRegionalPrefsLocales;
+
+  const size_t kMaxCachedPatterns = 15;
+  nsTHashMap<nsCStringHashKey, nsCString> mPatternCache;
+
+ private:
+  virtual ~OSPreferences();
+
+  static StaticRefPtr<OSPreferences> sInstance;
+
+  static bool CanonicalizeLanguageTag(nsCString& aLoc);
+
+  /**
+   * Helper methods to get formats from ICU; these will return false
+   * in case of error, in which case the caller cannot rely on aRetVal.
+   */
+  bool GetDateTimePatternForStyle(DateTimeFormatStyle aDateStyle,
+                                  DateTimeFormatStyle aTimeStyle,
+                                  const nsACString& aLocale,
+                                  nsACString& aRetVal);
+
+  bool GetDateTimeSkeletonForStyle(DateTimeFormatStyle aDateStyle,
+                                   DateTimeFormatStyle aTimeStyle,
+                                   const nsACString& aLocale,
+                                   nsACString& aRetVal);
+
+  bool OverrideDateTimePattern(DateTimeFormatStyle aDateStyle,
+                               DateTimeFormatStyle aTimeStyle,
+                               const nsACString& aLocale, nsACString& aRetVal);
+
+  /**
+   * This is a host environment specific method that will be implemented
+   * separately for each platform.
+   *
+   * It is only called when the cache is empty or invalidated.
+   *
+   * The return value indicates whether the function successfully
+   * resolved at least one locale.
+   */
+  bool ReadSystemLocales(nsTArray<nsCString>& aRetVal);
+
+  bool ReadRegionalPrefsLocales(nsTArray<nsCString>& aRetVal);
+
+  /**
+   * This is a host environment specific method that will be implemented
+   * separately for each platform.
+   *
+   * It is `best-effort` kind of API that attempts to construct the best
+   * possible date/time pattern for the given styles and locales.
+   *
+   * In case we fail to, or don't know how to retrieve the pattern in a
+   * given environment this function will return false.
+   * Callers should always be prepared to handle that scenario.
+   *
+   * The heuristic may depend on the OS API and HIG guidelines.
+   */
+  bool ReadDateTimePattern(DateTimeFormatStyle aDateFormatStyle,
+                           DateTimeFormatStyle aTimeFormatStyle,
+                           const nsACString& aLocale, nsACString& aRetVal);
+
+  /**
+   * This is called to override the hour cycle in the skeleton based upon
+   * the OS preference for AM/PM or 24 hour display.
+   */
+  void OverrideSkeletonHourCycle(bool aIs24Hour, nsAutoCString& aSkeleton);
+
+  /**
+   * This is called by the destructor to clean up any OS specific observers
+   * that are registered.
+   */
+  void RemoveObservers();
+
+  /**
+   * This is called by the destructor to clean up any OS specific observers
+   * that are registered.
+   */
+  static void PreferenceChanged(const char* aPrefName, void* /* aClosure */);
+};
+
+}  // namespace intl
+}  // namespace mozilla
+
+#endif /* mozilla_intl_IntlOSPreferences_h__ */