third_party/WebKit/Source/core/css/CSSFontSelector.cpp

/*
 * Copyright (C) 2007, 2008, 2011 Apple Inc. All rights reserved.
 *           (C) 2007, 2008 Nikolas Zimmermann <zimmermann@kde.org>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "core/css/CSSFontSelector.h"

#include "core/css/CSSFontSelectorClient.h"
#include "core/css/CSSSegmentedFontFace.h"
#include "core/css/CSSValueList.h"
#include "core/css/FontFaceSet.h"
#include "core/css/resolver/StyleResolver.h"
#include "core/dom/Document.h"
#include "core/frame/LocalFrame.h"
#include "core/frame/Settings.h"
#include "core/loader/FrameLoader.h"
#include "platform/RuntimeEnabledFeatures.h"
#include "platform/fonts/FontCache.h"
#include "platform/fonts/SimpleFontData.h"
#include "wtf/text/AtomicString.h"

namespace blink {

CSSFontSelector::CSSFontSelector(Document* document)
    : m_document(document),
      m_genericFontFamilySettings(
          document->frame()->settings()->genericFontFamilySettings()) {
  // FIXME: An old comment used to say there was no need to hold a reference to
  // m_document because "we are guaranteed to be destroyed before the document".
  // But there does not seem to be any such guarantee.
  ASSERT(m_document);
  DCHECK(m_document->frame());
  FontCache::fontCache()->addClient(this);
  FontFaceSet::from(*document)->addFontFacesToFontFaceCache(&m_fontFaceCache,
                                                            this);
}

CSSFontSelector::~CSSFontSelector() {}

void CSSFontSelector::registerForInvalidationCallbacks(
    CSSFontSelectorClient* client) {
  m_clients.add(client);
}

void CSSFontSelector::unregisterForInvalidationCallbacks(
    CSSFontSelectorClient* client) {
  m_clients.remove(client);
}

void CSSFontSelector::dispatchInvalidationCallbacks() {
  m_fontFaceCache.incrementVersion();

  HeapVector<Member<CSSFontSelectorClient>> clients;
  copyToVector(m_clients, clients);
  for (auto& client : clients)
    client->fontsNeedUpdate(this);
}

void CSSFontSelector::fontFaceInvalidated() {
  dispatchInvalidationCallbacks();
}

void CSSFontSelector::fontCacheInvalidated() {
  dispatchInvalidationCallbacks();
}

static AtomicString familyNameFromSettings(
    const GenericFontFamilySettings& settings,
    const FontDescription& fontDescription,
    const AtomicString& genericFamilyName) {
#if OS(ANDROID)
  if (fontDescription.genericFamily() == FontDescription::StandardFamily)
    return FontCache::getGenericFamilyNameForScript(
        FontFamilyNames::webkit_standard, fontDescription);

  if (genericFamilyName.startsWith("-webkit-"))
    return FontCache::getGenericFamilyNameForScript(genericFamilyName,
                                                    fontDescription);
#else
  UScriptCode script = fontDescription.script();
  if (fontDescription.genericFamily() == FontDescription::StandardFamily)
    return settings.standard(script);
  if (genericFamilyName == FontFamilyNames::webkit_serif)
    return settings.serif(script);
  if (genericFamilyName == FontFamilyNames::webkit_sans_serif)
    return settings.sansSerif(script);
  if (genericFamilyName == FontFamilyNames::webkit_cursive)
    return settings.cursive(script);
  if (genericFamilyName == FontFamilyNames::webkit_fantasy)
    return settings.fantasy(script);
  if (genericFamilyName == FontFamilyNames::webkit_monospace)
    return settings.fixed(script);
  if (genericFamilyName == FontFamilyNames::webkit_pictograph)
    return settings.pictograph(script);
  if (genericFamilyName == FontFamilyNames::webkit_standard)
    return settings.standard(script);
#endif
  return emptyAtom;
}

PassRefPtr<FontData> CSSFontSelector::getFontData(
    const FontDescription& fontDescription,
    const AtomicString& familyName) {
  if (CSSSegmentedFontFace* face =
          m_fontFaceCache.get(fontDescription, familyName))
    return face->getFontData(fontDescription);

  // Try to return the correct font based off our settings, in case we were
  // handed the generic font family name.
  AtomicString settingsFamilyName = familyNameFromSettings(
      m_genericFontFamilySettings, fontDescription, familyName);
  if (settingsFamilyName.isEmpty())
    return nullptr;

  return FontCache::fontCache()->getFontData(fontDescription,
                                             settingsFamilyName);
}

void CSSFontSelector::willUseFontData(const FontDescription& fontDescription,
                                      const AtomicString& family,
                                      const String& text) {
  CSSSegmentedFontFace* face = m_fontFaceCache.get(fontDescription, family);
  if (face)
    face->willUseFontData(fontDescription, text);
}

void CSSFontSelector::willUseRange(const FontDescription& fontDescription,
                                   const AtomicString& family,
                                   const FontDataForRangeSet& rangeSet) {
  CSSSegmentedFontFace* face = m_fontFaceCache.get(fontDescription, family);
  if (face)
    face->willUseRange(fontDescription, rangeSet);
}

bool CSSFontSelector::isPlatformFontAvailable(
    const FontDescription& fontDescription,
    const AtomicString& passedFamily) {
  AtomicString family = familyNameFromSettings(m_genericFontFamilySettings,
                                               fontDescription, passedFamily);
  if (family.isEmpty())
    family = passedFamily;
  return FontCache::fontCache()->isPlatformFontAvailable(fontDescription,
                                                         family);
}

void CSSFontSelector::updateGenericFontFamilySettings(Document& document) {
  if (!document.settings())
    return;
  m_genericFontFamilySettings =
      document.settings()->genericFontFamilySettings();
  fontCacheInvalidated();
}

DEFINE_TRACE(CSSFontSelector) {
  visitor->trace(m_document);
  visitor->trace(m_fontFaceCache);
  visitor->trace(m_clients);
  FontSelector::trace(visitor);
}

}  // namespace blink