| /* |
| * Copyright (C) 2004, 2006, 2008, 2010 Apple Inc. All rights reserved. |
| * |
| * 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 "third_party/blink/renderer/platform/wtf/text/text_codec_utf16.h" |
| |
| #include <memory> |
| #include "third_party/blink/renderer/platform/wtf/text/character_names.h" |
| #include "third_party/blink/renderer/platform/wtf/text/string_buffer.h" |
| #include "third_party/blink/renderer/platform/wtf/text/wtf_string.h" |
| |
| namespace WTF { |
| |
| void TextCodecUTF16::RegisterEncodingNames(EncodingNameRegistrar registrar) { |
| registrar("UTF-16LE", "UTF-16LE"); |
| registrar("UTF-16BE", "UTF-16BE"); |
| |
| registrar("ISO-10646-UCS-2", "UTF-16LE"); |
| registrar("UCS-2", "UTF-16LE"); |
| registrar("UTF-16", "UTF-16LE"); |
| registrar("Unicode", "UTF-16LE"); |
| registrar("csUnicode", "UTF-16LE"); |
| registrar("unicodeFEFF", "UTF-16LE"); |
| |
| registrar("unicodeFFFE", "UTF-16BE"); |
| } |
| |
| static std::unique_ptr<TextCodec> NewStreamingTextDecoderUTF16LE( |
| const TextEncoding&, |
| const void*) { |
| return std::make_unique<TextCodecUTF16>(true); |
| } |
| |
| static std::unique_ptr<TextCodec> NewStreamingTextDecoderUTF16BE( |
| const TextEncoding&, |
| const void*) { |
| return std::make_unique<TextCodecUTF16>(false); |
| } |
| |
| void TextCodecUTF16::RegisterCodecs(TextCodecRegistrar registrar) { |
| registrar("UTF-16LE", NewStreamingTextDecoderUTF16LE, nullptr); |
| registrar("UTF-16BE", NewStreamingTextDecoderUTF16BE, nullptr); |
| } |
| |
| String TextCodecUTF16::Decode(const char* bytes, |
| wtf_size_t length, |
| FlushBehavior flush, |
| bool, |
| bool& saw_error) { |
| // For compatibility reasons, ignore flush from fetch EOF. |
| const bool really_flush = flush != FlushBehavior::kDoNotFlush && |
| flush != FlushBehavior::kFetchEOF; |
| |
| if (!length) { |
| if (really_flush && (have_lead_byte_ || have_lead_surrogate_)) { |
| have_lead_byte_ = have_lead_surrogate_ = false; |
| saw_error = true; |
| return String(&kReplacementCharacter, 1); |
| } |
| return String(); |
| } |
| |
| const unsigned char* p = reinterpret_cast<const unsigned char*>(bytes); |
| const wtf_size_t num_bytes = length + have_lead_byte_; |
| const bool will_have_extra_byte = num_bytes & 1; |
| const wtf_size_t num_chars_in = num_bytes / 2; |
| const wtf_size_t max_chars_out = |
| num_chars_in + (have_lead_surrogate_ ? 1 : 0) + |
| (really_flush && will_have_extra_byte ? 1 : 0); |
| |
| StringBuffer<UChar> buffer(max_chars_out); |
| UChar* q = buffer.Characters(); |
| |
| for (wtf_size_t i = 0; i < num_chars_in; ++i) { |
| UChar c; |
| if (have_lead_byte_) { |
| c = little_endian_ ? (lead_byte_ | (p[0] << 8)) |
| : ((lead_byte_ << 8) | p[0]); |
| have_lead_byte_ = false; |
| ++p; |
| } else { |
| c = little_endian_ ? (p[0] | (p[1] << 8)) : ((p[0] << 8) | p[1]); |
| p += 2; |
| } |
| |
| // TODO(jsbell): If necessary for performance, m_haveLeadByte handling |
| // can be pulled out and this loop split into distinct cases for |
| // big/little endian. The logic from here to the end of the loop is |
| // constant with respect to m_haveLeadByte and m_littleEndian. |
| |
| if (have_lead_surrogate_ && U_IS_TRAIL(c)) { |
| *q++ = lead_surrogate_; |
| have_lead_surrogate_ = false; |
| *q++ = c; |
| } else { |
| if (have_lead_surrogate_) { |
| have_lead_surrogate_ = false; |
| saw_error = true; |
| *q++ = kReplacementCharacter; |
| } |
| |
| if (U_IS_LEAD(c)) { |
| have_lead_surrogate_ = true; |
| lead_surrogate_ = c; |
| } else if (U_IS_TRAIL(c)) { |
| saw_error = true; |
| *q++ = kReplacementCharacter; |
| } else { |
| *q++ = c; |
| } |
| } |
| } |
| |
| DCHECK(!have_lead_byte_); |
| if (will_have_extra_byte) { |
| have_lead_byte_ = true; |
| lead_byte_ = p[0]; |
| } |
| |
| if (really_flush && (have_lead_byte_ || have_lead_surrogate_)) { |
| have_lead_byte_ = have_lead_surrogate_ = false; |
| saw_error = true; |
| *q++ = kReplacementCharacter; |
| } |
| |
| buffer.Shrink(static_cast<wtf_size_t>(q - buffer.Characters())); |
| |
| return String::Adopt(buffer); |
| } |
| |
| std::string TextCodecUTF16::Encode(const UChar* characters, |
| wtf_size_t length, |
| UnencodableHandling) { |
| // We need to be sure we can double the length without overflowing. |
| // Since the passed-in length is the length of an actual existing |
| // character buffer, each character is two bytes, and we know |
| // the buffer doesn't occupy the entire address space, we can |
| // assert here that doubling the length does not overflow wtf_size_t |
| // and there's no need for a runtime check. |
| DCHECK_LE(length, std::numeric_limits<wtf_size_t>::max() / 2); |
| |
| std::string result(length * 2, '\0'); |
| |
| if (little_endian_) { |
| for (wtf_size_t i = 0; i < length; ++i) { |
| UChar c = characters[i]; |
| result[i * 2] = static_cast<char>(c); |
| result[i * 2 + 1] = c >> 8; |
| } |
| } else { |
| for (wtf_size_t i = 0; i < length; ++i) { |
| UChar c = characters[i]; |
| result[i * 2] = c >> 8; |
| result[i * 2 + 1] = static_cast<char>(c); |
| } |
| } |
| |
| return result; |
| } |
| |
| std::string TextCodecUTF16::Encode(const LChar* characters, |
| wtf_size_t length, |
| UnencodableHandling) { |
| // In the LChar case, we do actually need to perform this check in release. :) |
| CHECK_LE(length, std::numeric_limits<wtf_size_t>::max() / 2); |
| |
| std::string result(length * 2, '\0'); |
| |
| if (little_endian_) { |
| for (wtf_size_t i = 0; i < length; ++i) { |
| result[i * 2] = characters[i]; |
| result[i * 2 + 1] = 0; |
| } |
| } else { |
| for (wtf_size_t i = 0; i < length; ++i) { |
| result[i * 2] = 0; |
| result[i * 2 + 1] = characters[i]; |
| } |
| } |
| |
| return result; |
| } |
| |
| } // namespace WTF |