encoding.h 21.8 KB
Newer Older
1 2 3 4 5 6 7
// Copyright 2019 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.

#ifndef V8_INSPECTOR_PROTOCOL_ENCODING_ENCODING_H_
#define V8_INSPECTOR_PROTOCOL_ENCODING_ENCODING_H_

8
#include <algorithm>
9 10 11
#include <cstddef>
#include <cstdint>
#include <cstring>
12
#include <limits>
13 14 15 16 17
#include <memory>
#include <string>
#include <vector>

namespace v8_inspector_protocol_encoding {
18 19 20 21 22 23 24 25 26 27 28 29 30
// This library is designed to be portable. The only allowed dependency
// are the C/C++ standard libraries, up to C++11. We support both 32 bit
// and 64 architectures.
//
// Types used below:
// uint8_t: a byte, e.g. for raw bytes or UTF8 characters
// uint16_t: two bytes, e.g. for UTF16 characters
// For input parameters:
//   span<uint8_t>: pointer to bytes and length
//   span<uint16_t>: pointer to UTF16 chars and length
// For output parameters:
//   std::vector<uint8_t> - Owned segment of bytes / utf8 characters and length.
//   std::string - Same, for compatibility, even though char is signed.
31

32 33 34 35
// =============================================================================
// span - sequence of bytes
// =============================================================================

36
// This template is similar to std::span, which will be included in C++20.
37 38 39
template <typename T>
class span {
 public:
40
  using index_type = size_t;
41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88

  span() : data_(nullptr), size_(0) {}
  span(const T* data, index_type size) : data_(data), size_(size) {}

  const T* data() const { return data_; }

  const T* begin() const { return data_; }
  const T* end() const { return data_ + size_; }

  const T& operator[](index_type idx) const { return data_[idx]; }

  span<T> subspan(index_type offset, index_type count) const {
    return span(data_ + offset, count);
  }

  span<T> subspan(index_type offset) const {
    return span(data_ + offset, size_ - offset);
  }

  bool empty() const { return size_ == 0; }

  index_type size() const { return size_; }
  index_type size_bytes() const { return size_ * sizeof(T); }

 private:
  const T* data_;
  index_type size_;
};

template <typename T>
span<T> SpanFrom(const std::vector<T>& v) {
  return span<T>(v.data(), v.size());
}

template <size_t N>
span<uint8_t> SpanFrom(const char (&str)[N]) {
  return span<uint8_t>(reinterpret_cast<const uint8_t*>(str), N - 1);
}

inline span<uint8_t> SpanFrom(const char* str) {
  return str ? span<uint8_t>(reinterpret_cast<const uint8_t*>(str), strlen(str))
             : span<uint8_t>();
}

inline span<uint8_t> SpanFrom(const std::string& v) {
  return span<uint8_t>(reinterpret_cast<const uint8_t*>(v.data()), v.size());
}

89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104
// Less than / equality comparison functions for sorting / searching for byte
// spans. These are similar to absl::string_view's < and == operators.
inline bool SpanLessThan(span<uint8_t> x, span<uint8_t> y) noexcept {
  auto min_size = std::min(x.size(), y.size());
  const int r = min_size == 0 ? 0 : memcmp(x.data(), y.data(), min_size);
  return (r < 0) || (r == 0 && x.size() < y.size());
}

inline bool SpanEquals(span<uint8_t> x, span<uint8_t> y) noexcept {
  auto len = x.size();
  if (len != y.size())
    return false;
  return x.data() == y.data() || len == 0 ||
         std::memcmp(x.data(), y.data(), len) == 0;
}

105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127
// =============================================================================
// Status and Error codes
// =============================================================================
enum class Error {
  OK = 0,
  // JSON parsing errors - json_parser.{h,cc}.
  JSON_PARSER_UNPROCESSED_INPUT_REMAINS = 0x01,
  JSON_PARSER_STACK_LIMIT_EXCEEDED = 0x02,
  JSON_PARSER_NO_INPUT = 0x03,
  JSON_PARSER_INVALID_TOKEN = 0x04,
  JSON_PARSER_INVALID_NUMBER = 0x05,
  JSON_PARSER_INVALID_STRING = 0x06,
  JSON_PARSER_UNEXPECTED_ARRAY_END = 0x07,
  JSON_PARSER_COMMA_OR_ARRAY_END_EXPECTED = 0x08,
  JSON_PARSER_STRING_LITERAL_EXPECTED = 0x09,
  JSON_PARSER_COLON_EXPECTED = 0x0a,
  JSON_PARSER_UNEXPECTED_MAP_END = 0x0b,
  JSON_PARSER_COMMA_OR_MAP_END_EXPECTED = 0x0c,
  JSON_PARSER_VALUE_EXPECTED = 0x0d,

  CBOR_INVALID_INT32 = 0x0e,
  CBOR_INVALID_DOUBLE = 0x0f,
  CBOR_INVALID_ENVELOPE = 0x10,
128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143
  CBOR_ENVELOPE_CONTENTS_LENGTH_MISMATCH = 0x11,
  CBOR_MAP_OR_ARRAY_EXPECTED_IN_ENVELOPE = 0x12,
  CBOR_INVALID_STRING8 = 0x13,
  CBOR_INVALID_STRING16 = 0x14,
  CBOR_INVALID_BINARY = 0x15,
  CBOR_UNSUPPORTED_VALUE = 0x16,
  CBOR_NO_INPUT = 0x17,
  CBOR_INVALID_START_BYTE = 0x18,
  CBOR_UNEXPECTED_EOF_EXPECTED_VALUE = 0x19,
  CBOR_UNEXPECTED_EOF_IN_ARRAY = 0x1a,
  CBOR_UNEXPECTED_EOF_IN_MAP = 0x1b,
  CBOR_INVALID_MAP_KEY = 0x1c,
  CBOR_STACK_LIMIT_EXCEEDED = 0x1d,
  CBOR_TRAILING_JUNK = 0x1e,
  CBOR_MAP_START_EXPECTED = 0x1f,
  CBOR_MAP_STOP_EXPECTED = 0x20,
144 145 146 147 148 149 150 151 152 153
  CBOR_ARRAY_START_EXPECTED = 0x21,
  CBOR_ENVELOPE_SIZE_LIMIT_EXCEEDED = 0x22,

  BINDINGS_MANDATORY_FIELD_MISSING = 0x23,
  BINDINGS_BOOL_VALUE_EXPECTED = 0x24,
  BINDINGS_INT32_VALUE_EXPECTED = 0x25,
  BINDINGS_DOUBLE_VALUE_EXPECTED = 0x26,
  BINDINGS_STRING_VALUE_EXPECTED = 0x27,
  BINDINGS_STRING8_VALUE_EXPECTED = 0x28,
  BINDINGS_BINARY_VALUE_EXPECTED = 0x29,
154 155 156 157 158
};

// A status value with position that can be copied. The default status
// is OK. Usually, error status values should come with a valid position.
struct Status {
159
  static constexpr size_t npos() { return std::numeric_limits<size_t>::max(); }
160 161 162 163

  bool ok() const { return error == Error::OK; }

  Error error = Error::OK;
164 165
  size_t pos = npos();
  Status(Error error, size_t pos) : error(error), pos(pos) {}
166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310
  Status() = default;

  // Returns a 7 bit US-ASCII string, either "OK" or an error message
  // that includes the position.
  std::string ToASCIIString() const;

 private:
  std::string ToASCIIString(const char* msg) const;
};

// Handler interface for parser events emitted by a streaming parser.
// See cbor::NewCBOREncoder, cbor::ParseCBOR, json::NewJSONEncoder,
// json::ParseJSON.
class StreamingParserHandler {
 public:
  virtual ~StreamingParserHandler() = default;
  virtual void HandleMapBegin() = 0;
  virtual void HandleMapEnd() = 0;
  virtual void HandleArrayBegin() = 0;
  virtual void HandleArrayEnd() = 0;
  virtual void HandleString8(span<uint8_t> chars) = 0;
  virtual void HandleString16(span<uint16_t> chars) = 0;
  virtual void HandleBinary(span<uint8_t> bytes) = 0;
  virtual void HandleDouble(double value) = 0;
  virtual void HandleInt32(int32_t value) = 0;
  virtual void HandleBool(bool value) = 0;
  virtual void HandleNull() = 0;

  // The parser may send one error even after other events have already
  // been received. Client code is reponsible to then discard the
  // already processed events.
  // |error| must be an eror, as in, |error.is_ok()| can't be true.
  virtual void HandleError(Status error) = 0;
};

namespace cbor {
// The binary encoding for the inspector protocol follows the CBOR specification
// (RFC 7049). Additional constraints:
// - Only indefinite length maps and arrays are supported.
// - Maps and arrays are wrapped with an envelope, that is, a
//   CBOR tag with value 24 followed by a byte string specifying
//   the byte length of the enclosed map / array. The byte string
//   must use a 32 bit wide length.
// - At the top level, a message must be an indefinite length map
//   wrapped by an envelope.
// - Maximal size for messages is 2^32 (4 GB).
// - For scalars, we support only the int32_t range, encoded as
//   UNSIGNED/NEGATIVE (major types 0 / 1).
// - UTF16 strings, including with unbalanced surrogate pairs, are encoded
//   as CBOR BYTE_STRING (major type 2). For such strings, the number of
//   bytes encoded must be even.
// - UTF8 strings (major type 3) are supported.
// - 7 bit US-ASCII strings must always be encoded as UTF8 strings, never
//   as UTF16 strings.
// - Arbitrary byte arrays, in the inspector protocol called 'binary',
//   are encoded as BYTE_STRING (major type 2), prefixed with a byte
//   indicating base64 when rendered as JSON.

// =============================================================================
// Detecting CBOR content
// =============================================================================

// The first byte for an envelope, which we use for wrapping dictionaries
// and arrays; and the byte that indicates a byte string with 32 bit length.
// These two bytes start an envelope, and thereby also any CBOR message
// produced or consumed by this protocol. See also |EnvelopeEncoder| below.
uint8_t InitialByteForEnvelope();
uint8_t InitialByteFor32BitLengthByteString();

// Checks whether |msg| is a cbor message.
bool IsCBORMessage(span<uint8_t> msg);

// =============================================================================
// Encoding individual CBOR items
// =============================================================================

// Some constants for CBOR tokens that only take a single byte on the wire.
uint8_t EncodeTrue();
uint8_t EncodeFalse();
uint8_t EncodeNull();
uint8_t EncodeIndefiniteLengthArrayStart();
uint8_t EncodeIndefiniteLengthMapStart();
uint8_t EncodeStop();

// Encodes |value| as |UNSIGNED| (major type 0) iff >= 0, or |NEGATIVE|
// (major type 1) iff < 0.
void EncodeInt32(int32_t value, std::vector<uint8_t>* out);
void EncodeInt32(int32_t value, std::string* out);

// Encodes a UTF16 string as a BYTE_STRING (major type 2). Each utf16
// character in |in| is emitted with most significant byte first,
// appending to |out|.
void EncodeString16(span<uint16_t> in, std::vector<uint8_t>* out);
void EncodeString16(span<uint16_t> in, std::string* out);

// Encodes a UTF8 string |in| as STRING (major type 3).
void EncodeString8(span<uint8_t> in, std::vector<uint8_t>* out);
void EncodeString8(span<uint8_t> in, std::string* out);

// Encodes the given |latin1| string as STRING8.
// If any non-ASCII character is present, it will be represented
// as a 2 byte UTF8 sequence.
void EncodeFromLatin1(span<uint8_t> latin1, std::vector<uint8_t>* out);
void EncodeFromLatin1(span<uint8_t> latin1, std::string* out);

// Encodes the given |utf16| string as STRING8 if it's entirely US-ASCII.
// Otherwise, encodes as STRING16.
void EncodeFromUTF16(span<uint16_t> utf16, std::vector<uint8_t>* out);
void EncodeFromUTF16(span<uint16_t> utf16, std::string* out);

// Encodes arbitrary binary data in |in| as a BYTE_STRING (major type 2) with
// definitive length, prefixed with tag 22 indicating expected conversion to
// base64 (see RFC 7049, Table 3 and Section 2.4.4.2).
void EncodeBinary(span<uint8_t> in, std::vector<uint8_t>* out);
void EncodeBinary(span<uint8_t> in, std::string* out);

// Encodes / decodes a double as Major type 7 (SIMPLE_VALUE),
// with additional info = 27, followed by 8 bytes in big endian.
void EncodeDouble(double value, std::vector<uint8_t>* out);
void EncodeDouble(double value, std::string* out);

// =============================================================================
// cbor::EnvelopeEncoder - for wrapping submessages
// =============================================================================

// An envelope indicates the byte length of a wrapped item.
// We use this for maps and array, which allows the decoder
// to skip such (nested) values whole sale.
// It's implemented as a CBOR tag (major type 6) with additional
// info = 24, followed by a byte string with a 32 bit length value;
// so the maximal structure that we can wrap is 2^32 bits long.
// See also: https://tools.ietf.org/html/rfc7049#section-2.4.4.1
class EnvelopeEncoder {
 public:
  // Emits the envelope start bytes and records the position for the
  // byte size in |byte_size_pos_|. Also emits empty bytes for the
  // byte sisze so that encoding can continue.
  void EncodeStart(std::vector<uint8_t>* out);
  void EncodeStart(std::string* out);
  // This records the current size in |out| at position byte_size_pos_.
  // Returns true iff successful.
  bool EncodeStop(std::vector<uint8_t>* out);
  bool EncodeStop(std::string* out);

 private:
311
  size_t byte_size_pos_ = 0;
312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430
};

// =============================================================================
// cbor::NewCBOREncoder - for encoding from a streaming parser
// =============================================================================

// This can be used to convert to CBOR, by passing the return value to a parser
// that drives it. The handler will encode into |out|, and iff an error occurs
// it will set |status| to an error and clear |out|. Otherwise, |status.ok()|
// will be |true|.
std::unique_ptr<StreamingParserHandler> NewCBOREncoder(
    std::vector<uint8_t>* out,
    Status* status);
std::unique_ptr<StreamingParserHandler> NewCBOREncoder(std::string* out,
                                                       Status* status);

// =============================================================================
// cbor::CBORTokenizer - for parsing individual CBOR items
// =============================================================================

// Tags for the tokens within a CBOR message that CBORTokenizer understands.
// Note that this is not the same terminology as the CBOR spec (RFC 7049),
// but rather, our adaptation. For instance, we lump unsigned and signed
// major type into INT32 here (and disallow values outside the int32_t range).
enum class CBORTokenTag {
  // Encountered an error in the structure of the message. Consult
  // status() for details.
  ERROR_VALUE,
  // Booleans and NULL.
  TRUE_VALUE,
  FALSE_VALUE,
  NULL_VALUE,
  // An int32_t (signed 32 bit integer).
  INT32,
  // A double (64 bit floating point).
  DOUBLE,
  // A UTF8 string.
  STRING8,
  // A UTF16 string.
  STRING16,
  // A binary string.
  BINARY,
  // Starts an indefinite length map; after the map start we expect
  // alternating keys and values, followed by STOP.
  MAP_START,
  // Starts an indefinite length array; after the array start we
  // expect values, followed by STOP.
  ARRAY_START,
  // Ends a map or an array.
  STOP,
  // An envelope indicator, wrapping a map or array.
  // Internally this carries the byte length of the wrapped
  // map or array. While CBORTokenizer::Next() will read / skip the entire
  // envelope, CBORTokenizer::EnterEnvelope() reads the tokens
  // inside of it.
  ENVELOPE,
  // We've reached the end there is nothing else to read.
  DONE,
};

// The major types from RFC 7049 Section 2.1.
enum class MajorType {
  UNSIGNED = 0,
  NEGATIVE = 1,
  BYTE_STRING = 2,
  STRING = 3,
  ARRAY = 4,
  MAP = 5,
  TAG = 6,
  SIMPLE_VALUE = 7
};

// CBORTokenizer segments a CBOR message, presenting the tokens therein as
// numbers, strings, etc. This is not a complete CBOR parser, but makes it much
// easier to implement one (e.g. ParseCBOR, above). It can also be used to parse
// messages partially.
class CBORTokenizer {
 public:
  explicit CBORTokenizer(span<uint8_t> bytes);
  ~CBORTokenizer();

  // Identifies the current token that we're looking at,
  // or ERROR_VALUE (in which ase ::Status() has details)
  // or DONE (if we're past the last token).
  CBORTokenTag TokenTag() const;

  // Advances to the next token.
  void Next();
  // Can only be called if TokenTag() == CBORTokenTag::ENVELOPE.
  // While Next() would skip past the entire envelope / what it's
  // wrapping, EnterEnvelope positions the cursor inside of the envelope,
  // letting the client explore the nested structure.
  void EnterEnvelope();

  // If TokenTag() is CBORTokenTag::ERROR_VALUE, then Status().error describes
  // the error more precisely; otherwise it'll be set to Error::OK.
  // In either case, Status().pos is the current position.
  struct Status Status() const;

  // The following methods retrieve the token values. They can only
  // be called if TokenTag() matches.

  // To be called only if ::TokenTag() == CBORTokenTag::INT32.
  int32_t GetInt32() const;

  // To be called only if ::TokenTag() == CBORTokenTag::DOUBLE.
  double GetDouble() const;

  // To be called only if ::TokenTag() == CBORTokenTag::STRING8.
  span<uint8_t> GetString8() const;

  // Wire representation for STRING16 is low byte first (little endian).
  // To be called only if ::TokenTag() == CBORTokenTag::STRING16.
  span<uint8_t> GetString16WireRep() const;

  // To be called only if ::TokenTag() == CBORTokenTag::BINARY.
  span<uint8_t> GetBinary() const;

  // To be called only if ::TokenTag() == CBORTokenTag::ENVELOPE.
431 432 433 434 435 436 437 438 439 440 441
  // Returns the envelope including its payload; message which
  // can be passed to the CBORTokenizer constructor, which will
  // then see the envelope token first (looking at it a second time,
  // basically).
  span<uint8_t> GetEnvelope() const;

  // To be called only if ::TokenTag() == CBORTokenTag::ENVELOPE.
  // Returns only the payload inside the envelope, e.g., a map
  // or an array. This is not a complete message by our
  // IsCBORMessage definition, since it doesn't include the
  // enclosing envelope (the header, basically).
442 443 444 445
  span<uint8_t> GetEnvelopeContents() const;

 private:
  void ReadNextToken(bool enter_envelope);
446
  void SetToken(CBORTokenTag token, size_t token_byte_length);
447 448 449 450 451
  void SetError(Error error);

  span<uint8_t> bytes_;
  CBORTokenTag token_tag_;
  struct Status status_;
452
  size_t token_byte_length_;
453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481
  MajorType token_start_type_;
  uint64_t token_start_internal_value_;
};

// =============================================================================
// cbor::ParseCBOR - for receiving streaming parser events for CBOR messages
// =============================================================================

// Parses a CBOR encoded message from |bytes|, sending events to
// |out|. If an error occurs, sends |out->HandleError|, and parsing stops.
// The client is responsible for discarding the already received information in
// that case.
void ParseCBOR(span<uint8_t> bytes, StreamingParserHandler* out);

// =============================================================================
// cbor::AppendString8EntryToMap - for limited in-place editing of messages
// =============================================================================

// Modifies the |cbor| message by appending a new key/value entry at the end
// of the map. Patches up the envelope size; Status.ok() iff successful.
// If not successful, |cbor| may be corrupted after this call.
Status AppendString8EntryToCBORMap(span<uint8_t> string8_key,
                                   span<uint8_t> string8_value,
                                   std::vector<uint8_t>* cbor);
Status AppendString8EntryToCBORMap(span<uint8_t> string8_key,
                                   span<uint8_t> string8_value,
                                   std::string* cbor);

namespace internals {  // Exposed only for writing tests.
482
size_t ReadTokenStart(span<uint8_t> bytes,
483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549
                      cbor::MajorType* type,
                      uint64_t* value);

void WriteTokenStart(cbor::MajorType type,
                     uint64_t value,
                     std::vector<uint8_t>* encoded);
void WriteTokenStart(cbor::MajorType type,
                     uint64_t value,
                     std::string* encoded);
}  // namespace internals
}  // namespace cbor

namespace json {
// Client code must provide an instance. Implementation should delegate
// to whatever is appropriate.
class Platform {
 public:
  virtual ~Platform() = default;
  // Parses |str| into |result|. Returns false iff there are
  // leftover characters or parsing errors.
  virtual bool StrToD(const char* str, double* result) const = 0;

  // Prints |value| in a format suitable for JSON.
  virtual std::unique_ptr<char[]> DToStr(double value) const = 0;
};

// =============================================================================
// json::NewJSONEncoder - for encoding streaming parser events as JSON
// =============================================================================

// Returns a handler object which will write ascii characters to |out|.
// |status->ok()| will be false iff the handler routine HandleError() is called.
// In that case, we'll stop emitting output.
// Except for calling the HandleError routine at any time, the client
// code must call the Handle* methods in an order in which they'd occur
// in valid JSON; otherwise we may crash (the code uses assert).
std::unique_ptr<StreamingParserHandler> NewJSONEncoder(
    const Platform* platform,
    std::vector<uint8_t>* out,
    Status* status);
std::unique_ptr<StreamingParserHandler> NewJSONEncoder(const Platform* platform,
                                                       std::string* out,
                                                       Status* status);

// =============================================================================
// json::ParseJSON - for receiving streaming parser events for JSON
// =============================================================================

void ParseJSON(const Platform& platform,
               span<uint8_t> chars,
               StreamingParserHandler* handler);
void ParseJSON(const Platform& platform,
               span<uint16_t> chars,
               StreamingParserHandler* handler);

// =============================================================================
// json::ConvertCBORToJSON, json::ConvertJSONToCBOR - for transcoding
// =============================================================================
Status ConvertCBORToJSON(const Platform& platform,
                         span<uint8_t> cbor,
                         std::string* json);
Status ConvertCBORToJSON(const Platform& platform,
                         span<uint8_t> cbor,
                         std::vector<uint8_t>* json);
Status ConvertJSONToCBOR(const Platform& platform,
                         span<uint8_t> json,
                         std::vector<uint8_t>* cbor);
550 551 552
Status ConvertJSONToCBOR(const Platform& platform,
                         span<uint16_t> json,
                         std::vector<uint8_t>* cbor);
553 554 555
Status ConvertJSONToCBOR(const Platform& platform,
                         span<uint8_t> json,
                         std::string* cbor);
556 557 558
Status ConvertJSONToCBOR(const Platform& platform,
                         span<uint16_t> json,
                         std::string* cbor);
559 560 561 562
}  // namespace json
}  // namespace v8_inspector_protocol_encoding

#endif  // V8_INSPECTOR_PROTOCOL_ENCODING_ENCODING_H_