Add LayoutLocale class

third_party/WebKit/Source/platform/fonts/FontLocale.cpp

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "platform/fonts/FontLocale.h"
+
+#include "platform/Language.h"
+#include "platform/text/Hyphenation.h"
+#include "platform/text/LocaleToScriptMapping.h"
+#include "wtf/HashMap.h"
+#include "wtf/text/AtomicStringHash.h"
+#include "wtf/text/StringHash.h"
+
+#include <hb.h>
+
+namespace blink {
+
+using FontLocaleMap = HashMap<AtomicString, RefPtr<FontLocale>, CaseFoldingHash>;
+
+static FontLocaleMap& getLocaleMap()
+{
+    DEFINE_STATIC_LOCAL(FontLocaleMap, localeMap, ());
+    return localeMap;
+}
+
+const FontLocale* FontLocale::get(const AtomicString& locale)
+{
+    if (locale.isNull())
+        return nullptr;
+    auto result = getLocaleMap().add(locale, nullptr);
+    if (result.isNewEntry)
+        result.storedValue->value = adoptRef(new FontLocale(locale.lower()));
+    return result.storedValue->value.get();
+}
+
+static const FontLocale* computeDefaultLocale()
+{
+    AtomicString locale = defaultLanguage();
+    if (locale.isEmpty())
+        locale = AtomicString("en");
+    return FontLocale::get(locale);
+}
+
+const FontLocale& FontLocale::getDefault()
+{
+    DEFINE_STATIC_LOCAL(const FontLocale*, defaultLocale, (computeDefaultLocale()));
+    return *defaultLocale;
+}
+
+static hb_language_t toHarfbuzLanguage(const AtomicString& locale)
+{
+    CString localeAsLatin1 = locale.latin1();
+    return hb_language_from_string(localeAsLatin1.data(), localeAsLatin1.length());
+}
+
+FontLocale::FontLocale(const AtomicString& locale)
+    : m_string(locale)
+    , m_script(localeToScriptCodeForFontSelection(locale))
+    , m_harfbuzzLanguage(static_cast<const void*>(toHarfbuzLanguage(locale)))
+{
+}
+
+// SkFontMgr requires script-based locale names, like "zh-Hant" and "zh-Hans",
+// instead of "zh-CN" and "zh-TW".
+static CString toSkFontMgrLocale(const String& locale)
+{
+    if (!locale.startsWith("zh", TextCaseInsensitive))
+        return locale.ascii();
+
+    switch (localeToScriptCodeForFontSelection(locale)) {
+    case USCRIPT_SIMPLIFIED_HAN:
+        return "zh-Hans";
+    case USCRIPT_TRADITIONAL_HAN:
+        return "zh-Hant";
+    default:
+        return locale.ascii();
+    }
+}
+
+const CString& FontLocale::localeForSkFontMgr() const
+{
+    if (m_stringForSkFontMgr.isNull())
+        m_stringForSkFontMgr = toSkFontMgrLocale(m_string);
+    return m_stringForSkFontMgr;
+}
+
+Hyphenation* FontLocale::getHyphenation() const
+{
+    return Hyphenation::get(localeString());
+}
+
+} // namespace blink