| // Copyright 2011 the V8 project authors. All rights reserved. |
| // Redistribution and use in source and binary forms, with or without |
| // modification, are permitted provided that the following conditions are |
| // met: |
| // |
| // * Redistributions of source code must retain the above copyright |
| // notice, this list of conditions and the following disclaimer. |
| // * 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. |
| // * Neither the name of Google Inc. nor the names of its |
| // contributors may be used to endorse or promote products derived |
| // from this software without specific prior written permission. |
| // |
| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| // "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 THE COPYRIGHT |
| // OWNER 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. |
| |
| #ifndef V8_JSON_PARSER_H_ |
| #define V8_JSON_PARSER_H_ |
| |
| #include "v8.h" |
| |
| #include "char-predicates-inl.h" |
| #include "v8conversions.h" |
| #include "messages.h" |
| #include "spaces-inl.h" |
| #include "token.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| // A simple json parser. |
| template <bool seq_ascii> |
| class JsonParser BASE_EMBEDDED { |
| public: |
| static Handle<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()), |
| zone_(isolate_), |
| object_constructor_(isolate_->native_context()->object_function(), |
| isolate_), |
| position_(-1) { |
| FlattenString(source_); |
| pretenure_ = (source_length_ >= kPretenureTreshold) ? TENURED : NOT_TENURED; |
| |
| // Optimized fast case where we only have ASCII characters. |
| if (seq_ascii) { |
| seq_source_ = Handle<SeqOneByteString>::cast(source_); |
| } |
| } |
| |
| // Parse a string containing a single JSON value. |
| Handle<Object> ParseJson(); |
| |
| inline void Advance() { |
| position_++; |
| if (position_ >= source_length_) { |
| c0_ = kEndOfString; |
| } else if (seq_ascii) { |
| 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.IsAscii()) { |
| ASSERT_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-ASCII 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(); |
| |
| // 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 = 1024; |
| static const int kPretenureTreshold = 100 * 1024; |
| |
| |
| private: |
| Zone* zone() { return &zone_; } |
| |
| 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_ascii> |
| Handle<Object> JsonParser<seq_ascii>::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. |
| const char* message; |
| Factory* factory = this->factory(); |
| Handle<JSArray> array; |
| |
| switch (c0_) { |
| case kEndOfString: |
| message = "unexpected_eos"; |
| array = factory->NewJSArray(0); |
| break; |
| case '-': |
| case '0': |
| case '1': |
| case '2': |
| case '3': |
| case '4': |
| case '5': |
| case '6': |
| case '7': |
| case '8': |
| case '9': |
| message = "unexpected_token_number"; |
| array = factory->NewJSArray(0); |
| break; |
| case '"': |
| message = "unexpected_token_string"; |
| array = factory->NewJSArray(0); |
| break; |
| default: |
| message = "unexpected_token"; |
| Handle<Object> name = |
| LookupSingleCharacterStringFromCode(isolate_, c0_); |
| Handle<FixedArray> element = factory->NewFixedArray(1); |
| element->set(0, *name); |
| array = factory->NewJSArrayWithElements(element); |
| break; |
| } |
| |
| MessageLocation location(factory->NewScript(source_), |
| position_, |
| position_ + 1); |
| Handle<Object> result = factory->NewSyntaxError(message, array); |
| isolate()->Throw(*result, &location); |
| return Handle<Object>::null(); |
| } |
| return result; |
| } |
| |
| |
| // Parse any JSON value. |
| template <bool seq_ascii> |
| Handle<Object> JsonParser<seq_ascii>::ParseJsonValue() { |
| StackLimitCheck stack_check(isolate_); |
| if (stack_check.HasOverflowed()) { |
| isolate_->StackOverflow(); |
| return Handle<Object>::null(); |
| } |
| |
| 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(); |
| } |
| |
| |
| // Parse a JSON object. Position must be right at '{'. |
| template <bool seq_ascii> |
| Handle<Object> JsonParser<seq_ascii>::ParseJsonObject() { |
| HandleScope scope(isolate()); |
| Handle<JSObject> json_object = |
| factory()->NewJSObject(object_constructor(), pretenure_); |
| Handle<Map> map(json_object->map()); |
| ZoneList<Handle<Object> > properties(8, zone()); |
| ASSERT_EQ(c0_, '{'); |
| |
| bool transitioning = true; |
| |
| AdvanceSkipWhitespace(); |
| if (c0_ != '}') { |
| do { |
| if (c0_ != '"') return ReportUnexpectedCharacter(); |
| |
| int start_position = position_; |
| Advance(); |
| |
| uint32_t index = 0; |
| if (c0_ >= '0' && c0_ <= '9') { |
| // 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 > 5) ? 1 : 0)) break; |
| index = (index * 10) + d; |
| Advance(); |
| } while (c0_ >= '0' && c0_ <= '9'); |
| } |
| |
| if (c0_ == '"') { |
| // Successfully parsed index, parse and store element. |
| AdvanceSkipWhitespace(); |
| |
| if (c0_ != ':') return ReportUnexpectedCharacter(); |
| AdvanceSkipWhitespace(); |
| Handle<Object> value = ParseJsonValue(); |
| if (value.is_null()) return ReportUnexpectedCharacter(); |
| |
| JSObject::SetOwnElement(json_object, index, value, kNonStrictMode); |
| 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. |
| if (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_ascii) { |
| key = JSObject::ExpectedTransitionKey(map); |
| follow_expected = !key.is_null() && ParseJsonString(key); |
| } |
| // If the expected transition hits, follow it. |
| if (follow_expected) { |
| target = JSObject::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 = JSObject::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) { |
| int descriptor = map->NumberOfOwnDescriptors(); |
| PropertyDetails details = |
| target->instance_descriptors()->GetDetails(descriptor); |
| Representation expected_representation = details.representation(); |
| |
| if (value->FitsRepresentation(expected_representation)) { |
| // If the target representation is double and the value is already |
| // double, use the existing box. |
| if (FLAG_track_double_fields && |
| value->IsSmi() && |
| expected_representation.IsDouble()) { |
| value = factory()->NewHeapNumber( |
| Handle<Smi>::cast(value)->value()); |
| } |
| properties.Add(value, zone()); |
| map = target; |
| continue; |
| } else { |
| transitioning = false; |
| } |
| } |
| |
| // Commit the intermediate state to the object and stop transitioning. |
| JSObject::AllocateStorageForMap(json_object, map); |
| int length = properties.length(); |
| for (int i = 0; i < length; i++) { |
| Handle<Object> value = properties[i]; |
| json_object->FastPropertyAtPut(i, *value); |
| } |
| } else { |
| key = ParseJsonInternalizedString(); |
| if (key.is_null() || c0_ != ':') return ReportUnexpectedCharacter(); |
| |
| AdvanceSkipWhitespace(); |
| value = ParseJsonValue(); |
| if (value.is_null()) return ReportUnexpectedCharacter(); |
| } |
| |
| JSObject::SetLocalPropertyIgnoreAttributes( |
| json_object, key, value, NONE); |
| } while (MatchSkipWhiteSpace(',')); |
| if (c0_ != '}') { |
| return ReportUnexpectedCharacter(); |
| } |
| |
| // If we transitioned until the very end, transition the map now. |
| if (transitioning) { |
| JSObject::AllocateStorageForMap(json_object, map); |
| int length = properties.length(); |
| for (int i = 0; i < length; i++) { |
| Handle<Object> value = properties[i]; |
| json_object->FastPropertyAtPut(i, *value); |
| } |
| } |
| } |
| AdvanceSkipWhitespace(); |
| return scope.CloseAndEscape(json_object); |
| } |
| |
| // Parse a JSON array. Position must be right at '['. |
| template <bool seq_ascii> |
| Handle<Object> JsonParser<seq_ascii>::ParseJsonArray() { |
| HandleScope scope(isolate()); |
| ZoneList<Handle<Object> > elements(4, zone()); |
| ASSERT_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, pretenure_); |
| return scope.CloseAndEscape(json_array); |
| } |
| |
| |
| template <bool seq_ascii> |
| Handle<Object> JsonParser<seq_ascii>::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 ('0' <= c0_ && c0_ <= '9') 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 (c0_ >= '0' && c0_ <= '9'); |
| if (c0_ != '.' && c0_ != 'e' && c0_ != 'E' && digits < 10) { |
| SkipWhitespace(); |
| return Handle<Smi>(Smi::FromInt((negative ? -i : i)), isolate()); |
| } |
| } |
| if (c0_ == '.') { |
| Advance(); |
| if (c0_ < '0' || c0_ > '9') return ReportUnexpectedCharacter(); |
| do { |
| Advance(); |
| } while (c0_ >= '0' && c0_ <= '9'); |
| } |
| if (AsciiAlphaToLower(c0_) == 'e') { |
| Advance(); |
| if (c0_ == '-' || c0_ == '+') Advance(); |
| if (c0_ < '0' || c0_ > '9') return ReportUnexpectedCharacter(); |
| do { |
| Advance(); |
| } while (c0_ >= '0' && c0_ <= '9'); |
| } |
| int length = position_ - beg_pos; |
| double number; |
| if (seq_ascii) { |
| Vector<const uint8_t> chars(seq_source_->GetChars() + beg_pos, length); |
| number = StringToDouble(isolate()->unicode_cache(), |
| Vector<const char>::cast(chars), |
| NO_FLAGS, // Hex, octal or trailing junk. |
| OS::nan_value()); |
| } 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(), |
| // TODO(dcarney): Convert StringToDouble to uint_t. |
| Vector<const char>::cast(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); |
| } |
| |
| template <> |
| inline Handle<SeqOneByteString> NewRawString(Factory* factory, |
| int length, |
| PretenureFlag pretenure) { |
| return factory->NewRawOneByteString(length, pretenure); |
| } |
| |
| |
| // 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_ascii> |
| template <typename StringType, typename SinkChar> |
| Handle<String> JsonParser<seq_ascii>::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 |
| // ASCII characters, there's no need to test whether we can store the |
| // character. Otherwise check whether the UC16 source character can fit |
| // in the ASCII sink. |
| if (sizeof(SinkChar) == kUC16Size || |
| seq_ascii || |
| c0_ <= String::kMaxOneByteCharCode) { |
| SeqStringSet(seq_string, count++, c0_); |
| Advance(); |
| } else { |
| // StringType is SeqOneByteString and we just read a non-ASCII 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-ASCII char. |
| position_ -= 6; // Rewind position_ to \ in \uxxxx. |
| Advance(); |
| return SlowScanJsonString<SeqTwoByteString, uc16>(seq_string, |
| 0, |
| count); |
| } |
| } |
| default: |
| return Handle<String>::null(); |
| } |
| Advance(); |
| } |
| } |
| |
| ASSERT_EQ('"', c0_); |
| // Advance past the last '"'. |
| AdvanceSkipWhitespace(); |
| |
| // Shrink seq_string length to count and return. |
| return SeqString::Truncate(seq_string, count); |
| } |
| |
| |
| template <bool seq_ascii> |
| template <bool is_internalized> |
| Handle<String> JsonParser<seq_ascii>::ScanJsonString() { |
| ASSERT_EQ('"', c0_); |
| Advance(); |
| if (c0_ == '"') { |
| AdvanceSkipWhitespace(); |
| return factory()->empty_string(); |
| } |
| |
| if (seq_ascii && 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) : 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; |
| ASSERT_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 ASCII 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_ascii || 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_); |
| uint8_t* dest = SeqOneByteString::cast(*result)->GetChars(); |
| String::WriteToFlat(*source_, dest, beg_pos, position_); |
| |
| ASSERT_EQ('"', c0_); |
| // Advance past the last '"'. |
| AdvanceSkipWhitespace(); |
| return result; |
| } |
| |
| } } // namespace v8::internal |
| |
| #endif // V8_JSON_PARSER_H_ |