third_party/blink/renderer/platform/fonts/font_face_creation_params.h

/*
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 * modification, are permitted provided that the following conditions are
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#ifndef THIRD_PARTY_BLINK_RENDERER_PLATFORM_FONTS_FONT_FACE_CREATION_PARAMS_H_
#define THIRD_PARTY_BLINK_RENDERER_PLATFORM_FONTS_FONT_FACE_CREATION_PARAMS_H_

#include "build/build_config.h"
#include "third_party/blink/renderer/platform/wtf/allocator/allocator.h"
#include "third_party/blink/renderer/platform/wtf/text/atomic_string.h"
#include "third_party/blink/renderer/platform/wtf/text/string_hash.h"
#include "third_party/blink/renderer/platform/wtf/text/string_hasher.h"

namespace blink {

enum FontFaceCreationType {
  kCreateFontByFamily,
  kCreateFontByFciIdAndTtcIndex
};

class FontFaceCreationParams {
  USING_FAST_MALLOC(FontFaceCreationParams);

 public:
  FontFaceCreationParams()
      : creation_type_(kCreateFontByFamily),
        family_(AtomicString()),
        filename_(std::string()),
        fontconfig_interface_id_(0),
        ttc_index_(0) {}

  explicit FontFaceCreationParams(AtomicString family)
      : creation_type_(kCreateFontByFamily),
        family_(family),
        filename_(std::string()),
        fontconfig_interface_id_(0),
        ttc_index_(0) {
#if defined(OS_WIN)
    // Leading "@" in the font name enables Windows vertical flow flag for the
    // font.  Because we do vertical flow by ourselves, we don't want to use the
    // Windows feature.  IE disregards "@" regardless of the orientation, so we
    // follow the behavior and normalize the family name.
    family_ = (family_.IsEmpty() || family_[0] != '@')
                  ? family_
                  : AtomicString(family_.Impl()->Substring(1));
#endif
  }

  FontFaceCreationParams(const std::string& filename,
                         int fontconfig_interface_id,
                         int ttc_index = 0)
      : creation_type_(kCreateFontByFciIdAndTtcIndex),
        filename_(filename),
        fontconfig_interface_id_(fontconfig_interface_id),
        ttc_index_(ttc_index) {}

  FontFaceCreationType CreationType() const { return creation_type_; }
  const AtomicString& Family() const {
    DCHECK_EQ(creation_type_, kCreateFontByFamily);
    return family_;
  }
  const std::string& Filename() const {
    DCHECK_EQ(creation_type_, kCreateFontByFciIdAndTtcIndex);
    return filename_;
  }
  int FontconfigInterfaceId() const {
    DCHECK_EQ(creation_type_, kCreateFontByFciIdAndTtcIndex);
    return fontconfig_interface_id_;
  }
  int TtcIndex() const {
    DCHECK_EQ(creation_type_, kCreateFontByFciIdAndTtcIndex);
    return ttc_index_;
  }

  unsigned GetHash() const {
    if (creation_type_ == kCreateFontByFciIdAndTtcIndex) {
      StringHasher hasher;
      // Hashing the filename and ints in this way is sensitive to character
      // encoding and endianness. However, since the hash is not transferred
      // over a network or permanently stored and only used for the runtime of
      // Chromium, this is not a concern.
      hasher.AddCharacters(reinterpret_cast<const LChar*>(filename_.data()),
                           static_cast<unsigned>(filename_.length()));
      hasher.AddCharacters(reinterpret_cast<const LChar*>(&ttc_index_),
                           sizeof(ttc_index_));
      hasher.AddCharacters(
          reinterpret_cast<const LChar*>(&fontconfig_interface_id_),
          sizeof(fontconfig_interface_id_));
      return hasher.GetHash();
    }
    return CaseFoldingHash::GetHash(family_.IsEmpty() ? "" : family_);
  }

  bool operator==(const FontFaceCreationParams& other) const {
    return creation_type_ == other.creation_type_ &&
           DeprecatedEqualIgnoringCase(family_, other.family_) &&
           filename_ == other.filename_ &&
           fontconfig_interface_id_ == other.fontconfig_interface_id_ &&
           ttc_index_ == other.ttc_index_;
  }

 private:
  FontFaceCreationType creation_type_;
  AtomicString family_;
  std::string filename_;
  int fontconfig_interface_id_;
  int ttc_index_;
};

}  // namespace blink

#endif  // THIRD_PARTY_BLINK_RENDERER_PLATFORM_FONTS_FONT_FACE_CREATION_PARAMS_H_