michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "mozilla/dom/FallbackEncoding.h"
michael@0: 
michael@0: #include "mozilla/dom/EncodingUtils.h"
michael@0: #include "nsUConvPropertySearch.h"
michael@0: #include "nsIChromeRegistry.h"
michael@0: #include "mozilla/Preferences.h"
michael@0: #include "mozilla/Services.h"
michael@0: 
michael@0: namespace mozilla {
michael@0: namespace dom {
michael@0: 
michael@0: static const char* localesFallbacks[][3] = {
michael@0: #include "localesfallbacks.properties.h"
michael@0: };
michael@0: 
michael@0: static const char* domainsFallbacks[][3] = {
michael@0: #include "domainsfallbacks.properties.h"
michael@0: };
michael@0: 
michael@0: static const char* nonParticipatingDomains[][3] = {
michael@0: #include "nonparticipatingdomains.properties.h"
michael@0: };
michael@0: 
michael@0: FallbackEncoding* FallbackEncoding::sInstance = nullptr;
michael@0: bool FallbackEncoding::sGuessFallbackFromTopLevelDomain = true;
michael@0: 
michael@0: FallbackEncoding::FallbackEncoding()
michael@0: {
michael@0:   MOZ_COUNT_CTOR(FallbackEncoding);
michael@0:   MOZ_ASSERT(!FallbackEncoding::sInstance,
michael@0:              "Singleton already exists.");
michael@0: }
michael@0: 
michael@0: FallbackEncoding::~FallbackEncoding()
michael@0: {
michael@0:   MOZ_COUNT_DTOR(FallbackEncoding);
michael@0: }
michael@0: 
michael@0: void
michael@0: FallbackEncoding::Get(nsACString& aFallback)
michael@0: {
michael@0:   if (!mFallback.IsEmpty()) {
michael@0:     aFallback = mFallback;
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   const nsAdoptingCString& override =
michael@0:     Preferences::GetCString("intl.charset.fallback.override");
michael@0:   // Don't let the user break things by setting the override to unreasonable
michael@0:   // values via about:config
michael@0:   if (!EncodingUtils::FindEncodingForLabel(override, mFallback) ||
michael@0:       !EncodingUtils::IsAsciiCompatible(mFallback) ||
michael@0:       mFallback.EqualsLiteral("UTF-8")) {
michael@0:     mFallback.Truncate();
michael@0:   }
michael@0: 
michael@0:   if (!mFallback.IsEmpty()) {
michael@0:     aFallback = mFallback;
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   nsAutoCString locale;
michael@0:   nsCOMPtr<nsIXULChromeRegistry> registry =
michael@0:     mozilla::services::GetXULChromeRegistryService();
michael@0:   if (registry) {
michael@0:     registry->GetSelectedLocale(NS_LITERAL_CSTRING("global"), locale);
michael@0:   }
michael@0: 
michael@0:   // Let's lower case the string just in case unofficial language packs
michael@0:   // don't stick to conventions.
michael@0:   ToLowerCase(locale); // ASCII lowercasing with CString input!
michael@0: 
michael@0:   // Special case Traditional Chinese before throwing away stuff after the
michael@0:   // language itself. Today we only ship zh-TW, but be defensive about
michael@0:   // possible future values.
michael@0:   if (locale.EqualsLiteral("zh-tw") ||
michael@0:       locale.EqualsLiteral("zh-hk") ||
michael@0:       locale.EqualsLiteral("zh-mo") ||
michael@0:       locale.EqualsLiteral("zh-hant")) {
michael@0:     mFallback.AssignLiteral("Big5");
michael@0:     aFallback = mFallback;
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   // Throw away regions and other variants to accommodate weird stuff seen
michael@0:   // in telemetry--apparently unofficial language packs.
michael@0:   int32_t index = locale.FindChar('-');
michael@0:   if (index >= 0) {
michael@0:     locale.Truncate(index);
michael@0:   }
michael@0: 
michael@0:   if (NS_FAILED(nsUConvPropertySearch::SearchPropertyValue(
michael@0:       localesFallbacks, ArrayLength(localesFallbacks), locale, mFallback))) {
michael@0:     mFallback.AssignLiteral("windows-1252");
michael@0:   }
michael@0: 
michael@0:   aFallback = mFallback;
michael@0: }
michael@0: 
michael@0: void
michael@0: FallbackEncoding::FromLocale(nsACString& aFallback)
michael@0: {
michael@0:   MOZ_ASSERT(FallbackEncoding::sInstance,
michael@0:              "Using uninitialized fallback cache.");
michael@0:   FallbackEncoding::sInstance->Get(aFallback);
michael@0: }
michael@0: 
michael@0: // PrefChangedFunc
michael@0: void
michael@0: FallbackEncoding::PrefChanged(const char*, void*)
michael@0: {
michael@0:   MOZ_ASSERT(FallbackEncoding::sInstance,
michael@0:              "Pref callback called with null fallback cache.");
michael@0:   FallbackEncoding::sInstance->Invalidate();
michael@0: }
michael@0: 
michael@0: void
michael@0: FallbackEncoding::Initialize()
michael@0: {
michael@0:   MOZ_ASSERT(!FallbackEncoding::sInstance,
michael@0:              "Initializing pre-existing fallback cache.");
michael@0:   FallbackEncoding::sInstance = new FallbackEncoding;
michael@0:   Preferences::RegisterCallback(FallbackEncoding::PrefChanged,
michael@0:                                 "intl.charset.fallback.override",
michael@0:                                 nullptr);
michael@0:   Preferences::RegisterCallback(FallbackEncoding::PrefChanged,
michael@0:                                 "general.useragent.locale",
michael@0:                                 nullptr);
michael@0:   Preferences::AddBoolVarCache(&sGuessFallbackFromTopLevelDomain,
michael@0:                                "intl.charset.fallback.tld");
michael@0: }
michael@0: 
michael@0: void
michael@0: FallbackEncoding::Shutdown()
michael@0: {
michael@0:   MOZ_ASSERT(FallbackEncoding::sInstance,
michael@0:              "Releasing non-existent fallback cache.");
michael@0:   delete FallbackEncoding::sInstance;
michael@0:   FallbackEncoding::sInstance = nullptr;
michael@0: }
michael@0: 
michael@0: bool
michael@0: FallbackEncoding::IsParticipatingTopLevelDomain(const nsACString& aTLD)
michael@0: {
michael@0:   nsAutoCString dummy;
michael@0:   return NS_FAILED(nsUConvPropertySearch::SearchPropertyValue(
michael@0:       nonParticipatingDomains,
michael@0:       ArrayLength(nonParticipatingDomains),
michael@0:       aTLD,
michael@0:       dummy));
michael@0: }
michael@0: 
michael@0: void
michael@0: FallbackEncoding::FromTopLevelDomain(const nsACString& aTLD,
michael@0:                                      nsACString& aFallback)
michael@0: {
michael@0:   if (NS_FAILED(nsUConvPropertySearch::SearchPropertyValue(
michael@0:       domainsFallbacks, ArrayLength(domainsFallbacks), aTLD, aFallback))) {
michael@0:     aFallback.AssignLiteral("windows-1252");
michael@0:   }
michael@0: }
michael@0: 
michael@0: } // namespace dom
michael@0: } // namespace mozilla