third_party/blink/renderer/core/css/css_markup.cc

/*
 * Copyright (C) 2003 Lars Knoll (knoll@kde.org)
 * Copyright (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
 * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc.
 * All rights reserved.
 * Copyright (C) 2007 Nicholas Shanks <webkit@nickshanks.com>
 * Copyright (C) 2008 Eric Seidel <eric@webkit.org>
 * Copyright (C) 2009 Torch Mobile Inc. All rights reserved.
 * (http://www.torchmobile.com/)
 * Copyright (C) 2012 Adobe Systems Incorporated. All rights reserved.
 * Copyright (C) 2012 Intel Corporation. All rights reserved.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public License
 * along with this library; see the file COPYING.LIB.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 */

#include "third_party/blink/renderer/core/css/css_markup.h"

#include "third_party/blink/renderer/core/css/parser/css_parser_idioms.h"
#include "third_party/blink/renderer/platform/wtf/text/string_buffer.h"
#include "third_party/blink/renderer/platform/wtf/text/string_builder.h"

namespace blink {

template <typename CharacterType>
static inline bool IsCSSTokenizerIdentifier(const CharacterType* characters,
                                            unsigned length) {
  const CharacterType* end = characters + length;

  // -?
  if (characters != end && characters[0] == '-')
    ++characters;

  // {nmstart}
  if (characters == end || !IsNameStartCodePoint(characters[0]))
    return false;
  ++characters;

  // {nmchar}*
  for (; characters != end; ++characters) {
    if (!IsNameCodePoint(characters[0]))
      return false;
  }

  return true;
}

// "ident" from the CSS tokenizer, minus backslash-escape sequences
static bool IsCSSTokenizerIdentifier(const String& string) {
  unsigned length = string.length();

  if (!length)
    return false;

  if (string.Is8Bit())
    return IsCSSTokenizerIdentifier(string.Characters8(), length);
  return IsCSSTokenizerIdentifier(string.Characters16(), length);
}

static void SerializeCharacter(UChar32 c, StringBuilder& append_to) {
  append_to.Append('\\');
  append_to.Append(c);
}

static void SerializeCharacterAsCodePoint(UChar32 c, StringBuilder& append_to) {
  append_to.AppendFormat("\\%x ", c);
}

void SerializeIdentifier(const String& identifier,
                         StringBuilder& append_to,
                         bool skip_start_checks) {
  bool is_first = !skip_start_checks;
  bool is_second = false;
  bool is_first_char_hyphen = false;
  unsigned index = 0;
  while (index < identifier.length()) {
    UChar32 c = identifier.CharacterStartingAt(index);
    if (c == 0) {
      // Check for lone surrogate which characterStartingAt does not return.
      c = identifier[index];
    }

    index += U16_LENGTH(c);

    if (c == 0)
      append_to.Append(0xfffd);
    else if (c <= 0x1f || c == 0x7f ||
             (0x30 <= c && c <= 0x39 &&
              (is_first || (is_second && is_first_char_hyphen))))
      SerializeCharacterAsCodePoint(c, append_to);
    else if (c == 0x2d && is_first && index == identifier.length())
      SerializeCharacter(c, append_to);
    else if (0x80 <= c || c == 0x2d || c == 0x5f || (0x30 <= c && c <= 0x39) ||
             (0x41 <= c && c <= 0x5a) || (0x61 <= c && c <= 0x7a))
      append_to.Append(c);
    else
      SerializeCharacter(c, append_to);

    if (is_first) {
      is_first = false;
      is_second = true;
      is_first_char_hyphen = (c == 0x2d);
    } else if (is_second) {
      is_second = false;
    }
  }
}

void SerializeString(const String& string, StringBuilder& append_to) {
  append_to.Append('\"');

  unsigned index = 0;
  while (index < string.length()) {
    UChar32 c = string.CharacterStartingAt(index);
    index += U16_LENGTH(c);

    if (c <= 0x1f || c == 0x7f)
      SerializeCharacterAsCodePoint(c, append_to);
    else if (c == 0x22 || c == 0x5c)
      SerializeCharacter(c, append_to);
    else
      append_to.Append(c);
  }

  append_to.Append('\"');
}

String SerializeString(const String& string) {
  StringBuilder builder;
  SerializeString(string, builder);
  return builder.ToString();
}

String SerializeURI(const String& string) {
  return "url(" + SerializeString(string) + ")";
}

String SerializeFontFamily(const String& string) {
  return IsCSSTokenizerIdentifier(string) ? string : SerializeString(string);
}

}  // namespace blink