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author | Allan Sandfeld Jensen <allan.jensen@theqtcompany.com> | 2016-01-25 11:39:07 +0100 |
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committer | Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com> | 2016-01-25 15:20:42 +0000 |
commit | 6c91641271e536ffaa88a1dff5127e42ee99a91e (patch) | |
tree | 703d9dd49602377ddc90cbf886aad37913f2496b /chromium/v8/src/json-parser.h | |
parent | b145b7fafd36f0c260d6a768c81fc14e32578099 (diff) | |
download | qtwebengine-chromium-6c91641271e536ffaa88a1dff5127e42ee99a91e.tar.gz |
BASELINE: Update Chromium to 49.0.2623.23
Also adds missing printing sources.
Change-Id: I3726b8f0c7d6751c9fc846096c571fadca7108cd
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com>
Diffstat (limited to 'chromium/v8/src/json-parser.h')
-rw-r--r-- | chromium/v8/src/json-parser.h | 850 |
1 files changed, 0 insertions, 850 deletions
diff --git a/chromium/v8/src/json-parser.h b/chromium/v8/src/json-parser.h deleted file mode 100644 index cac49798598..00000000000 --- a/chromium/v8/src/json-parser.h +++ /dev/null @@ -1,850 +0,0 @@ -// Copyright 2011 the V8 project 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_JSON_PARSER_H_ -#define V8_JSON_PARSER_H_ - -#include "src/char-predicates.h" -#include "src/conversions.h" -#include "src/debug/debug.h" -#include "src/factory.h" -#include "src/messages.h" -#include "src/scanner.h" -#include "src/token.h" -#include "src/transitions.h" -#include "src/types.h" - -namespace v8 { -namespace internal { - -enum ParseElementResult { kElementFound, kElementNotFound, kNullHandle }; - - -// A simple json parser. -template <bool seq_one_byte> -class JsonParser BASE_EMBEDDED { - public: - MUST_USE_RESULT static MaybeHandle<Object> Parse(Handle<String> source) { - return JsonParser(source).ParseJson(); - } - - static const int kEndOfString = -1; - - private: - explicit JsonParser(Handle<String> source) - : source_(source), - source_length_(source->length()), - isolate_(source->map()->GetHeap()->isolate()), - factory_(isolate_->factory()), - object_constructor_(isolate_->native_context()->object_function(), - isolate_), - position_(-1) { - source_ = String::Flatten(source_); - pretenure_ = (source_length_ >= kPretenureTreshold) ? TENURED : NOT_TENURED; - - // Optimized fast case where we only have Latin1 characters. - if (seq_one_byte) { - seq_source_ = Handle<SeqOneByteString>::cast(source_); - } - } - - // Parse a string containing a single JSON value. - MaybeHandle<Object> ParseJson(); - - inline void Advance() { - position_++; - if (position_ >= source_length_) { - c0_ = kEndOfString; - } else if (seq_one_byte) { - c0_ = seq_source_->SeqOneByteStringGet(position_); - } else { - c0_ = source_->Get(position_); - } - } - - // The JSON lexical grammar is specified in the ECMAScript 5 standard, - // section 15.12.1.1. The only allowed whitespace characters between tokens - // are tab, carriage-return, newline and space. - - inline void AdvanceSkipWhitespace() { - do { - Advance(); - } while (c0_ == ' ' || c0_ == '\t' || c0_ == '\n' || c0_ == '\r'); - } - - inline void SkipWhitespace() { - while (c0_ == ' ' || c0_ == '\t' || c0_ == '\n' || c0_ == '\r') { - Advance(); - } - } - - inline uc32 AdvanceGetChar() { - Advance(); - return c0_; - } - - // Checks that current charater is c. - // If so, then consume c and skip whitespace. - inline bool MatchSkipWhiteSpace(uc32 c) { - if (c0_ == c) { - AdvanceSkipWhitespace(); - return true; - } - return false; - } - - // A JSON string (production JSONString) is subset of valid JavaScript string - // literals. The string must only be double-quoted (not single-quoted), and - // the only allowed backslash-escapes are ", /, \, b, f, n, r, t and - // four-digit hex escapes (uXXXX). Any other use of backslashes is invalid. - Handle<String> ParseJsonString() { - return ScanJsonString<false>(); - } - - bool ParseJsonString(Handle<String> expected) { - int length = expected->length(); - if (source_->length() - position_ - 1 > length) { - DisallowHeapAllocation no_gc; - String::FlatContent content = expected->GetFlatContent(); - if (content.IsOneByte()) { - DCHECK_EQ('"', c0_); - const uint8_t* input_chars = seq_source_->GetChars() + position_ + 1; - const uint8_t* expected_chars = content.ToOneByteVector().start(); - for (int i = 0; i < length; i++) { - uint8_t c0 = input_chars[i]; - if (c0 != expected_chars[i] || c0 == '"' || c0 < 0x20 || c0 == '\\') { - return false; - } - } - if (input_chars[length] == '"') { - position_ = position_ + length + 1; - AdvanceSkipWhitespace(); - return true; - } - } - } - return false; - } - - Handle<String> ParseJsonInternalizedString() { - return ScanJsonString<true>(); - } - - template <bool is_internalized> - Handle<String> ScanJsonString(); - // Creates a new string and copies prefix[start..end] into the beginning - // of it. Then scans the rest of the string, adding characters after the - // prefix. Called by ScanJsonString when reaching a '\' or non-Latin1 char. - template <typename StringType, typename SinkChar> - Handle<String> SlowScanJsonString(Handle<String> prefix, int start, int end); - - // A JSON number (production JSONNumber) is a subset of the valid JavaScript - // decimal number literals. - // It includes an optional minus sign, must have at least one - // digit before and after a decimal point, may not have prefixed zeros (unless - // the integer part is zero), and may include an exponent part (e.g., "e-10"). - // Hexadecimal and octal numbers are not allowed. - Handle<Object> ParseJsonNumber(); - - // Parse a single JSON value from input (grammar production JSONValue). - // A JSON value is either a (double-quoted) string literal, a number literal, - // one of "true", "false", or "null", or an object or array literal. - Handle<Object> ParseJsonValue(); - - // Parse a JSON object literal (grammar production JSONObject). - // An object literal is a squiggly-braced and comma separated sequence - // (possibly empty) of key/value pairs, where the key is a JSON string - // literal, the value is a JSON value, and the two are separated by a colon. - // A JSON array doesn't allow numbers and identifiers as keys, like a - // JavaScript array. - Handle<Object> ParseJsonObject(); - - // Helper for ParseJsonObject. Parses the form "123": obj, which is recorded - // as an element, not a property. - ParseElementResult ParseElement(Handle<JSObject> json_object); - - // Parses a JSON array literal (grammar production JSONArray). An array - // literal is a square-bracketed and comma separated sequence (possibly empty) - // of JSON values. - // A JSON array doesn't allow leaving out values from the sequence, nor does - // it allow a terminal comma, like a JavaScript array does. - Handle<Object> ParseJsonArray(); - - - // Mark that a parsing error has happened at the current token, and - // return a null handle. Primarily for readability. - inline Handle<Object> ReportUnexpectedCharacter() { - return Handle<Object>::null(); - } - - inline Isolate* isolate() { return isolate_; } - inline Factory* factory() { return factory_; } - inline Handle<JSFunction> object_constructor() { return object_constructor_; } - - static const int kInitialSpecialStringLength = 32; - static const int kPretenureTreshold = 100 * 1024; - - - private: - Zone* zone() { return &zone_; } - - void CommitStateToJsonObject(Handle<JSObject> json_object, Handle<Map> map, - ZoneList<Handle<Object> >* properties); - - Handle<String> source_; - int source_length_; - Handle<SeqOneByteString> seq_source_; - - PretenureFlag pretenure_; - Isolate* isolate_; - Factory* factory_; - Zone zone_; - Handle<JSFunction> object_constructor_; - uc32 c0_; - int position_; -}; - -template <bool seq_one_byte> -MaybeHandle<Object> JsonParser<seq_one_byte>::ParseJson() { - // Advance to the first character (possibly EOS) - AdvanceSkipWhitespace(); - Handle<Object> result = ParseJsonValue(); - if (result.is_null() || c0_ != kEndOfString) { - // Some exception (for example stack overflow) is already pending. - if (isolate_->has_pending_exception()) return Handle<Object>::null(); - - // Parse failed. Current character is the unexpected token. - Factory* factory = this->factory(); - MessageTemplate::Template message; - Handle<String> argument; - - switch (c0_) { - case kEndOfString: - message = MessageTemplate::kUnexpectedEOS; - break; - case '-': - case '0': - case '1': - case '2': - case '3': - case '4': - case '5': - case '6': - case '7': - case '8': - case '9': - message = MessageTemplate::kUnexpectedTokenNumber; - break; - case '"': - message = MessageTemplate::kUnexpectedTokenString; - break; - default: - message = MessageTemplate::kUnexpectedToken; - argument = factory->LookupSingleCharacterStringFromCode(c0_); - break; - } - - Handle<Script> script(factory->NewScript(source_)); - // We should sent compile error event because we compile JSON object in - // separated source file. - isolate()->debug()->OnCompileError(script); - MessageLocation location(script, position_, position_ + 1); - Handle<Object> error = factory->NewSyntaxError(message, argument); - return isolate()->template Throw<Object>(error, &location); - } - return result; -} - - -// Parse any JSON value. -template <bool seq_one_byte> -Handle<Object> JsonParser<seq_one_byte>::ParseJsonValue() { - StackLimitCheck stack_check(isolate_); - if (stack_check.HasOverflowed()) { - isolate_->StackOverflow(); - return Handle<Object>::null(); - } - - if (stack_check.InterruptRequested()) { - ExecutionAccess access(isolate_); - // Avoid blocking GC in long running parser (v8:3974). - isolate_->stack_guard()->HandleGCInterrupt(); - } - - if (c0_ == '"') return ParseJsonString(); - if ((c0_ >= '0' && c0_ <= '9') || c0_ == '-') return ParseJsonNumber(); - if (c0_ == '{') return ParseJsonObject(); - if (c0_ == '[') return ParseJsonArray(); - if (c0_ == 'f') { - if (AdvanceGetChar() == 'a' && AdvanceGetChar() == 'l' && - AdvanceGetChar() == 's' && AdvanceGetChar() == 'e') { - AdvanceSkipWhitespace(); - return factory()->false_value(); - } - return ReportUnexpectedCharacter(); - } - if (c0_ == 't') { - if (AdvanceGetChar() == 'r' && AdvanceGetChar() == 'u' && - AdvanceGetChar() == 'e') { - AdvanceSkipWhitespace(); - return factory()->true_value(); - } - return ReportUnexpectedCharacter(); - } - if (c0_ == 'n') { - if (AdvanceGetChar() == 'u' && AdvanceGetChar() == 'l' && - AdvanceGetChar() == 'l') { - AdvanceSkipWhitespace(); - return factory()->null_value(); - } - return ReportUnexpectedCharacter(); - } - return ReportUnexpectedCharacter(); -} - - -template <bool seq_one_byte> -ParseElementResult JsonParser<seq_one_byte>::ParseElement( - Handle<JSObject> json_object) { - uint32_t index = 0; - // Maybe an array index, try to parse it. - if (c0_ == '0') { - // With a leading zero, the string has to be "0" only to be an index. - Advance(); - } else { - do { - int d = c0_ - '0'; - if (index > 429496729U - ((d + 3) >> 3)) break; - index = (index * 10) + d; - Advance(); - } while (IsDecimalDigit(c0_)); - } - - if (c0_ == '"') { - // Successfully parsed index, parse and store element. - AdvanceSkipWhitespace(); - - if (c0_ == ':') { - AdvanceSkipWhitespace(); - Handle<Object> value = ParseJsonValue(); - if (!value.is_null()) { - JSObject::SetOwnElementIgnoreAttributes(json_object, index, value, NONE) - .Assert(); - return kElementFound; - } else { - return kNullHandle; - } - } - } - return kElementNotFound; -} - -// Parse a JSON object. Position must be right at '{'. -template <bool seq_one_byte> -Handle<Object> JsonParser<seq_one_byte>::ParseJsonObject() { - HandleScope scope(isolate()); - Handle<JSObject> json_object = - factory()->NewJSObject(object_constructor(), pretenure_); - Handle<Map> map(json_object->map()); - int descriptor = 0; - ZoneList<Handle<Object> > properties(8, zone()); - DCHECK_EQ(c0_, '{'); - - bool transitioning = true; - - AdvanceSkipWhitespace(); - if (c0_ != '}') { - do { - if (c0_ != '"') return ReportUnexpectedCharacter(); - - int start_position = position_; - Advance(); - - if (IsDecimalDigit(c0_)) { - ParseElementResult element_result = ParseElement(json_object); - if (element_result == kNullHandle) return Handle<Object>::null(); - if (element_result == kElementFound) continue; - } - // Not an index, fallback to the slow path. - - position_ = start_position; -#ifdef DEBUG - c0_ = '"'; -#endif - - Handle<String> key; - Handle<Object> value; - - // Try to follow existing transitions as long as possible. Once we stop - // transitioning, no transition can be found anymore. - DCHECK(transitioning); - // First check whether there is a single expected transition. If so, try - // to parse it first. - bool follow_expected = false; - Handle<Map> target; - if (seq_one_byte) { - key = TransitionArray::ExpectedTransitionKey(map); - follow_expected = !key.is_null() && ParseJsonString(key); - } - // If the expected transition hits, follow it. - if (follow_expected) { - target = TransitionArray::ExpectedTransitionTarget(map); - } else { - // If the expected transition failed, parse an internalized string and - // try to find a matching transition. - key = ParseJsonInternalizedString(); - if (key.is_null()) return ReportUnexpectedCharacter(); - - target = TransitionArray::FindTransitionToField(map, key); - // If a transition was found, follow it and continue. - transitioning = !target.is_null(); - } - if (c0_ != ':') return ReportUnexpectedCharacter(); - - AdvanceSkipWhitespace(); - value = ParseJsonValue(); - if (value.is_null()) return ReportUnexpectedCharacter(); - - if (transitioning) { - PropertyDetails details = - target->instance_descriptors()->GetDetails(descriptor); - Representation expected_representation = details.representation(); - - if (value->FitsRepresentation(expected_representation)) { - if (expected_representation.IsHeapObject() && - !target->instance_descriptors() - ->GetFieldType(descriptor) - ->NowContains(value)) { - Handle<HeapType> value_type( - value->OptimalType(isolate(), expected_representation)); - Map::GeneralizeFieldType(target, descriptor, - expected_representation, value_type); - } - DCHECK(target->instance_descriptors() - ->GetFieldType(descriptor) - ->NowContains(value)); - properties.Add(value, zone()); - map = target; - descriptor++; - continue; - } else { - transitioning = false; - } - } - - DCHECK(!transitioning); - - // Commit the intermediate state to the object and stop transitioning. - CommitStateToJsonObject(json_object, map, &properties); - - JSObject::DefinePropertyOrElementIgnoreAttributes(json_object, key, value) - .Check(); - } while (transitioning && MatchSkipWhiteSpace(',')); - - // If we transitioned until the very end, transition the map now. - if (transitioning) { - CommitStateToJsonObject(json_object, map, &properties); - } else { - while (MatchSkipWhiteSpace(',')) { - HandleScope local_scope(isolate()); - if (c0_ != '"') return ReportUnexpectedCharacter(); - - int start_position = position_; - Advance(); - - if (IsDecimalDigit(c0_)) { - ParseElementResult element_result = ParseElement(json_object); - if (element_result == kNullHandle) return Handle<Object>::null(); - if (element_result == kElementFound) continue; - } - // Not an index, fallback to the slow path. - - position_ = start_position; -#ifdef DEBUG - c0_ = '"'; -#endif - - Handle<String> key; - Handle<Object> value; - - key = ParseJsonInternalizedString(); - if (key.is_null() || c0_ != ':') return ReportUnexpectedCharacter(); - - AdvanceSkipWhitespace(); - value = ParseJsonValue(); - if (value.is_null()) return ReportUnexpectedCharacter(); - - JSObject::DefinePropertyOrElementIgnoreAttributes(json_object, key, - value).Check(); - } - } - - if (c0_ != '}') { - return ReportUnexpectedCharacter(); - } - } - AdvanceSkipWhitespace(); - return scope.CloseAndEscape(json_object); -} - - -template <bool seq_one_byte> -void JsonParser<seq_one_byte>::CommitStateToJsonObject( - Handle<JSObject> json_object, Handle<Map> map, - ZoneList<Handle<Object> >* properties) { - JSObject::AllocateStorageForMap(json_object, map); - DCHECK(!json_object->map()->is_dictionary_map()); - - DisallowHeapAllocation no_gc; - - int length = properties->length(); - for (int i = 0; i < length; i++) { - Handle<Object> value = (*properties)[i]; - json_object->WriteToField(i, *value); - } -} - - -// Parse a JSON array. Position must be right at '['. -template <bool seq_one_byte> -Handle<Object> JsonParser<seq_one_byte>::ParseJsonArray() { - HandleScope scope(isolate()); - ZoneList<Handle<Object> > elements(4, zone()); - DCHECK_EQ(c0_, '['); - - AdvanceSkipWhitespace(); - if (c0_ != ']') { - do { - Handle<Object> element = ParseJsonValue(); - if (element.is_null()) return ReportUnexpectedCharacter(); - elements.Add(element, zone()); - } while (MatchSkipWhiteSpace(',')); - if (c0_ != ']') { - return ReportUnexpectedCharacter(); - } - } - AdvanceSkipWhitespace(); - // Allocate a fixed array with all the elements. - Handle<FixedArray> fast_elements = - factory()->NewFixedArray(elements.length(), pretenure_); - for (int i = 0, n = elements.length(); i < n; i++) { - fast_elements->set(i, *elements[i]); - } - Handle<Object> json_array = factory()->NewJSArrayWithElements( - fast_elements, FAST_ELEMENTS, Strength::WEAK, pretenure_); - return scope.CloseAndEscape(json_array); -} - - -template <bool seq_one_byte> -Handle<Object> JsonParser<seq_one_byte>::ParseJsonNumber() { - bool negative = false; - int beg_pos = position_; - if (c0_ == '-') { - Advance(); - negative = true; - } - if (c0_ == '0') { - Advance(); - // Prefix zero is only allowed if it's the only digit before - // a decimal point or exponent. - if (IsDecimalDigit(c0_)) return ReportUnexpectedCharacter(); - } else { - int i = 0; - int digits = 0; - if (c0_ < '1' || c0_ > '9') return ReportUnexpectedCharacter(); - do { - i = i * 10 + c0_ - '0'; - digits++; - Advance(); - } while (IsDecimalDigit(c0_)); - if (c0_ != '.' && c0_ != 'e' && c0_ != 'E' && digits < 10) { - SkipWhitespace(); - return Handle<Smi>(Smi::FromInt((negative ? -i : i)), isolate()); - } - } - if (c0_ == '.') { - Advance(); - if (!IsDecimalDigit(c0_)) return ReportUnexpectedCharacter(); - do { - Advance(); - } while (IsDecimalDigit(c0_)); - } - if (AsciiAlphaToLower(c0_) == 'e') { - Advance(); - if (c0_ == '-' || c0_ == '+') Advance(); - if (!IsDecimalDigit(c0_)) return ReportUnexpectedCharacter(); - do { - Advance(); - } while (IsDecimalDigit(c0_)); - } - int length = position_ - beg_pos; - double number; - if (seq_one_byte) { - Vector<const uint8_t> chars(seq_source_->GetChars() + beg_pos, length); - number = StringToDouble(isolate()->unicode_cache(), chars, - NO_FLAGS, // Hex, octal or trailing junk. - std::numeric_limits<double>::quiet_NaN()); - } else { - Vector<uint8_t> buffer = Vector<uint8_t>::New(length); - String::WriteToFlat(*source_, buffer.start(), beg_pos, position_); - Vector<const uint8_t> result = - Vector<const uint8_t>(buffer.start(), length); - number = StringToDouble(isolate()->unicode_cache(), - result, - NO_FLAGS, // Hex, octal or trailing junk. - 0.0); - buffer.Dispose(); - } - SkipWhitespace(); - return factory()->NewNumber(number, pretenure_); -} - - -template <typename StringType> -inline void SeqStringSet(Handle<StringType> seq_str, int i, uc32 c); - -template <> -inline void SeqStringSet(Handle<SeqTwoByteString> seq_str, int i, uc32 c) { - seq_str->SeqTwoByteStringSet(i, c); -} - -template <> -inline void SeqStringSet(Handle<SeqOneByteString> seq_str, int i, uc32 c) { - seq_str->SeqOneByteStringSet(i, c); -} - -template <typename StringType> -inline Handle<StringType> NewRawString(Factory* factory, - int length, - PretenureFlag pretenure); - -template <> -inline Handle<SeqTwoByteString> NewRawString(Factory* factory, - int length, - PretenureFlag pretenure) { - return factory->NewRawTwoByteString(length, pretenure).ToHandleChecked(); -} - -template <> -inline Handle<SeqOneByteString> NewRawString(Factory* factory, - int length, - PretenureFlag pretenure) { - return factory->NewRawOneByteString(length, pretenure).ToHandleChecked(); -} - - -// Scans the rest of a JSON string starting from position_ and writes -// prefix[start..end] along with the scanned characters into a -// sequential string of type StringType. -template <bool seq_one_byte> -template <typename StringType, typename SinkChar> -Handle<String> JsonParser<seq_one_byte>::SlowScanJsonString( - Handle<String> prefix, int start, int end) { - int count = end - start; - int max_length = count + source_length_ - position_; - int length = Min(max_length, Max(kInitialSpecialStringLength, 2 * count)); - Handle<StringType> seq_string = - NewRawString<StringType>(factory(), length, pretenure_); - // Copy prefix into seq_str. - SinkChar* dest = seq_string->GetChars(); - String::WriteToFlat(*prefix, dest, start, end); - - while (c0_ != '"') { - // Check for control character (0x00-0x1f) or unterminated string (<0). - if (c0_ < 0x20) return Handle<String>::null(); - if (count >= length) { - // We need to create a longer sequential string for the result. - return SlowScanJsonString<StringType, SinkChar>(seq_string, 0, count); - } - if (c0_ != '\\') { - // If the sink can contain UC16 characters, or source_ contains only - // Latin1 characters, there's no need to test whether we can store the - // character. Otherwise check whether the UC16 source character can fit - // in the Latin1 sink. - if (sizeof(SinkChar) == kUC16Size || seq_one_byte || - c0_ <= String::kMaxOneByteCharCode) { - SeqStringSet(seq_string, count++, c0_); - Advance(); - } else { - // StringType is SeqOneByteString and we just read a non-Latin1 char. - return SlowScanJsonString<SeqTwoByteString, uc16>(seq_string, 0, count); - } - } else { - Advance(); // Advance past the \. - switch (c0_) { - case '"': - case '\\': - case '/': - SeqStringSet(seq_string, count++, c0_); - break; - case 'b': - SeqStringSet(seq_string, count++, '\x08'); - break; - case 'f': - SeqStringSet(seq_string, count++, '\x0c'); - break; - case 'n': - SeqStringSet(seq_string, count++, '\x0a'); - break; - case 'r': - SeqStringSet(seq_string, count++, '\x0d'); - break; - case 't': - SeqStringSet(seq_string, count++, '\x09'); - break; - case 'u': { - uc32 value = 0; - for (int i = 0; i < 4; i++) { - Advance(); - int digit = HexValue(c0_); - if (digit < 0) { - return Handle<String>::null(); - } - value = value * 16 + digit; - } - if (sizeof(SinkChar) == kUC16Size || - value <= String::kMaxOneByteCharCode) { - SeqStringSet(seq_string, count++, value); - break; - } else { - // StringType is SeqOneByteString and we just read a non-Latin1 - // char. - position_ -= 6; // Rewind position_ to \ in \uxxxx. - Advance(); - return SlowScanJsonString<SeqTwoByteString, uc16>(seq_string, - 0, - count); - } - } - default: - return Handle<String>::null(); - } - Advance(); - } - } - - DCHECK_EQ('"', c0_); - // Advance past the last '"'. - AdvanceSkipWhitespace(); - - // Shrink seq_string length to count and return. - return SeqString::Truncate(seq_string, count); -} - - -template <bool seq_one_byte> -template <bool is_internalized> -Handle<String> JsonParser<seq_one_byte>::ScanJsonString() { - DCHECK_EQ('"', c0_); - Advance(); - if (c0_ == '"') { - AdvanceSkipWhitespace(); - return factory()->empty_string(); - } - - if (seq_one_byte && is_internalized) { - // Fast path for existing internalized strings. If the the string being - // parsed is not a known internalized string, contains backslashes or - // unexpectedly reaches the end of string, return with an empty handle. - uint32_t running_hash = isolate()->heap()->HashSeed(); - int position = position_; - uc32 c0 = c0_; - do { - if (c0 == '\\') { - c0_ = c0; - int beg_pos = position_; - position_ = position; - return SlowScanJsonString<SeqOneByteString, uint8_t>(source_, - beg_pos, - position_); - } - if (c0 < 0x20) return Handle<String>::null(); - if (static_cast<uint32_t>(c0) > - unibrow::Utf16::kMaxNonSurrogateCharCode) { - running_hash = - StringHasher::AddCharacterCore(running_hash, - unibrow::Utf16::LeadSurrogate(c0)); - running_hash = - StringHasher::AddCharacterCore(running_hash, - unibrow::Utf16::TrailSurrogate(c0)); - } else { - running_hash = StringHasher::AddCharacterCore(running_hash, c0); - } - position++; - if (position >= source_length_) return Handle<String>::null(); - c0 = seq_source_->SeqOneByteStringGet(position); - } while (c0 != '"'); - int length = position - position_; - uint32_t hash = (length <= String::kMaxHashCalcLength) - ? StringHasher::GetHashCore(running_hash) - : static_cast<uint32_t>(length); - Vector<const uint8_t> string_vector( - seq_source_->GetChars() + position_, length); - StringTable* string_table = isolate()->heap()->string_table(); - uint32_t capacity = string_table->Capacity(); - uint32_t entry = StringTable::FirstProbe(hash, capacity); - uint32_t count = 1; - Handle<String> result; - while (true) { - Object* element = string_table->KeyAt(entry); - if (element == isolate()->heap()->undefined_value()) { - // Lookup failure. - result = factory()->InternalizeOneByteString( - seq_source_, position_, length); - break; - } - if (element != isolate()->heap()->the_hole_value() && - String::cast(element)->IsOneByteEqualTo(string_vector)) { - result = Handle<String>(String::cast(element), isolate()); -#ifdef DEBUG - uint32_t hash_field = - (hash << String::kHashShift) | String::kIsNotArrayIndexMask; - DCHECK_EQ(static_cast<int>(result->Hash()), - static_cast<int>(hash_field >> String::kHashShift)); -#endif - break; - } - entry = StringTable::NextProbe(entry, count++, capacity); - } - position_ = position; - // Advance past the last '"'. - AdvanceSkipWhitespace(); - return result; - } - - int beg_pos = position_; - // Fast case for Latin1 only without escape characters. - do { - // Check for control character (0x00-0x1f) or unterminated string (<0). - if (c0_ < 0x20) return Handle<String>::null(); - if (c0_ != '\\') { - if (seq_one_byte || c0_ <= String::kMaxOneByteCharCode) { - Advance(); - } else { - return SlowScanJsonString<SeqTwoByteString, uc16>(source_, - beg_pos, - position_); - } - } else { - return SlowScanJsonString<SeqOneByteString, uint8_t>(source_, - beg_pos, - position_); - } - } while (c0_ != '"'); - int length = position_ - beg_pos; - Handle<String> result = - factory()->NewRawOneByteString(length, pretenure_).ToHandleChecked(); - uint8_t* dest = SeqOneByteString::cast(*result)->GetChars(); - String::WriteToFlat(*source_, dest, beg_pos, position_); - - DCHECK_EQ('"', c0_); - // Advance past the last '"'. - AdvanceSkipWhitespace(); - return result; -} - -} } // namespace v8::internal - -#endif // V8_JSON_PARSER_H_ |