| // 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_DATE_DATEPARSER_INL_H_ |
| #define V8_DATE_DATEPARSER_INL_H_ |
| |
| #include "src/date/dateparser.h" |
| #include "src/execution/isolate.h" |
| #include "src/strings/char-predicates-inl.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| template <typename Char> |
| bool DateParser::Parse(Isolate* isolate, Vector<Char> str, double* out) { |
| InputReader<Char> in(str); |
| DateStringTokenizer<Char> scanner(&in); |
| TimeZoneComposer tz; |
| TimeComposer time; |
| DayComposer day; |
| |
| // Specification: |
| // Accept ES5 ISO 8601 date-time-strings or legacy dates compatible |
| // with Safari. |
| // ES5 ISO 8601 dates: |
| // [('-'|'+')yy]yyyy[-MM[-DD]][THH:mm[:ss[.sss]][Z|(+|-)hh:mm]] |
| // where yyyy is in the range 0000..9999 and |
| // +/-yyyyyy is in the range -999999..+999999 - |
| // but -000000 is invalid (year zero must be positive), |
| // MM is in the range 01..12, |
| // DD is in the range 01..31, |
| // MM and DD defaults to 01 if missing,, |
| // HH is generally in the range 00..23, but can be 24 if mm, ss |
| // and sss are zero (or missing), representing midnight at the |
| // end of a day, |
| // mm and ss are in the range 00..59, |
| // sss is in the range 000..999, |
| // hh is in the range 00..23, |
| // mm, ss, and sss default to 00 if missing, and |
| // timezone defaults to Z if missing |
| // (following Safari, ISO actually demands local time). |
| // Extensions: |
| // We also allow sss to have more or less than three digits (but at |
| // least one). |
| // We allow hh:mm to be specified as hhmm. |
| // Legacy dates: |
| // Any unrecognized word before the first number is ignored. |
| // Parenthesized text is ignored. |
| // An unsigned number followed by ':' is a time value, and is |
| // added to the TimeComposer. A number followed by '::' adds a second |
| // zero as well. A number followed by '.' is also a time and must be |
| // followed by milliseconds. |
| // Any other number is a date component and is added to DayComposer. |
| // A month name (or really: any word having the same first three letters |
| // as a month name) is recorded as a named month in the Day composer. |
| // A word recognizable as a time-zone is recorded as such, as is |
| // '(+|-)(hhmm|hh:)'. |
| // Legacy dates don't allow extra signs ('+' or '-') or umatched ')' |
| // after a number has been read (before the first number, any garbage |
| // is allowed). |
| // Intersection of the two: |
| // A string that matches both formats (e.g. 1970-01-01) will be |
| // parsed as an ES5 date-time string - which means it will default |
| // to UTC time-zone. That's unavoidable if following the ES5 |
| // specification. |
| // After a valid "T" has been read while scanning an ES5 datetime string, |
| // the input can no longer be a valid legacy date, since the "T" is a |
| // garbage string after a number has been read. |
| |
| // First try getting as far as possible with as ES5 Date Time String. |
| DateToken next_unhandled_token = ParseES5DateTime(&scanner, &day, &time, &tz); |
| if (next_unhandled_token.IsInvalid()) return false; |
| bool has_read_number = !day.IsEmpty(); |
| // If there's anything left, continue with the legacy parser. |
| bool legacy_parser = false; |
| for (DateToken token = next_unhandled_token; !token.IsEndOfInput(); |
| token = scanner.Next()) { |
| if (token.IsNumber()) { |
| legacy_parser = true; |
| has_read_number = true; |
| int n = token.number(); |
| if (scanner.SkipSymbol(':')) { |
| if (scanner.SkipSymbol(':')) { |
| // n + "::" |
| if (!time.IsEmpty()) return false; |
| time.Add(n); |
| time.Add(0); |
| } else { |
| // n + ":" |
| if (!time.Add(n)) return false; |
| if (scanner.Peek().IsSymbol('.')) scanner.Next(); |
| } |
| } else if (scanner.SkipSymbol('.') && time.IsExpecting(n)) { |
| time.Add(n); |
| if (!scanner.Peek().IsNumber()) return false; |
| int n = ReadMilliseconds(scanner.Next()); |
| if (n < 0) return false; |
| time.AddFinal(n); |
| } else if (tz.IsExpecting(n)) { |
| tz.SetAbsoluteMinute(n); |
| } else if (time.IsExpecting(n)) { |
| time.AddFinal(n); |
| // Require end, white space, "Z", "+" or "-" immediately after |
| // finalizing time. |
| DateToken peek = scanner.Peek(); |
| if (!peek.IsEndOfInput() && !peek.IsWhiteSpace() && |
| !peek.IsKeywordZ() && !peek.IsAsciiSign()) |
| return false; |
| } else { |
| if (!day.Add(n)) return false; |
| scanner.SkipSymbol('-'); |
| } |
| } else if (token.IsKeyword()) { |
| legacy_parser = true; |
| // Parse a "word" (sequence of chars. >= 'A'). |
| KeywordType type = token.keyword_type(); |
| int value = token.keyword_value(); |
| if (type == AM_PM && !time.IsEmpty()) { |
| time.SetHourOffset(value); |
| } else if (type == MONTH_NAME) { |
| day.SetNamedMonth(value); |
| scanner.SkipSymbol('-'); |
| } else if (type == TIME_ZONE_NAME && has_read_number) { |
| tz.Set(value); |
| } else { |
| // Garbage words are illegal if a number has been read. |
| if (has_read_number) return false; |
| // The first number has to be separated from garbage words by |
| // whitespace or other separators. |
| if (scanner.Peek().IsNumber()) return false; |
| } |
| } else if (token.IsAsciiSign() && (tz.IsUTC() || !time.IsEmpty())) { |
| legacy_parser = true; |
| // Parse UTC offset (only after UTC or time). |
| tz.SetSign(token.ascii_sign()); |
| // The following number may be empty. |
| int n = 0; |
| int length = 0; |
| if (scanner.Peek().IsNumber()) { |
| DateToken token = scanner.Next(); |
| length = token.length(); |
| n = token.number(); |
| } |
| has_read_number = true; |
| |
| if (scanner.Peek().IsSymbol(':')) { |
| tz.SetAbsoluteHour(n); |
| // TODO(littledan): Use minutes as part of timezone? |
| tz.SetAbsoluteMinute(kNone); |
| } else if (length == 2 || length == 1) { |
| // Handle time zones like GMT-8 |
| tz.SetAbsoluteHour(n); |
| tz.SetAbsoluteMinute(0); |
| } else if (length == 4 || length == 3) { |
| // Looks like the hhmm format |
| tz.SetAbsoluteHour(n / 100); |
| tz.SetAbsoluteMinute(n % 100); |
| } else { |
| // No need to accept time zones like GMT-12345 |
| return false; |
| } |
| } else if ((token.IsAsciiSign() || token.IsSymbol(')')) && |
| has_read_number) { |
| // Extra sign or ')' is illegal if a number has been read. |
| return false; |
| } else { |
| // Ignore other characters and whitespace. |
| } |
| } |
| |
| bool success = day.Write(out) && time.Write(out) && tz.Write(out); |
| |
| if (legacy_parser && success) { |
| isolate->CountUsage(v8::Isolate::kLegacyDateParser); |
| } |
| |
| return success; |
| } |
| |
| template <typename CharType> |
| DateParser::DateToken DateParser::DateStringTokenizer<CharType>::Scan() { |
| int pre_pos = in_->position(); |
| if (in_->IsEnd()) return DateToken::EndOfInput(); |
| if (in_->IsAsciiDigit()) { |
| int n = in_->ReadUnsignedNumeral(); |
| int length = in_->position() - pre_pos; |
| return DateToken::Number(n, length); |
| } |
| if (in_->Skip(':')) return DateToken::Symbol(':'); |
| if (in_->Skip('-')) return DateToken::Symbol('-'); |
| if (in_->Skip('+')) return DateToken::Symbol('+'); |
| if (in_->Skip('.')) return DateToken::Symbol('.'); |
| if (in_->Skip(')')) return DateToken::Symbol(')'); |
| if (in_->IsAsciiAlphaOrAbove()) { |
| DCHECK_EQ(KeywordTable::kPrefixLength, 3); |
| uint32_t buffer[3] = {0, 0, 0}; |
| int length = in_->ReadWord(buffer, 3); |
| int index = KeywordTable::Lookup(buffer, length); |
| return DateToken::Keyword(KeywordTable::GetType(index), |
| KeywordTable::GetValue(index), length); |
| } |
| if (in_->SkipWhiteSpace()) { |
| return DateToken::WhiteSpace(in_->position() - pre_pos); |
| } |
| if (in_->SkipParentheses()) { |
| return DateToken::Unknown(); |
| } |
| in_->Next(); |
| return DateToken::Unknown(); |
| } |
| |
| template <typename Char> |
| bool DateParser::InputReader<Char>::SkipWhiteSpace() { |
| if (IsWhiteSpaceOrLineTerminator(ch_)) { |
| Next(); |
| return true; |
| } |
| return false; |
| } |
| |
| template <typename Char> |
| bool DateParser::InputReader<Char>::SkipParentheses() { |
| if (ch_ != '(') return false; |
| int balance = 0; |
| do { |
| if (ch_ == ')') |
| --balance; |
| else if (ch_ == '(') |
| ++balance; |
| Next(); |
| } while (balance > 0 && ch_); |
| return true; |
| } |
| |
| template <typename Char> |
| DateParser::DateToken DateParser::ParseES5DateTime( |
| DateStringTokenizer<Char>* scanner, DayComposer* day, TimeComposer* time, |
| TimeZoneComposer* tz) { |
| DCHECK(day->IsEmpty()); |
| DCHECK(time->IsEmpty()); |
| DCHECK(tz->IsEmpty()); |
| |
| // Parse mandatory date string: [('-'|'+')yy]yyyy[':'MM[':'DD]] |
| if (scanner->Peek().IsAsciiSign()) { |
| // Keep the sign token, so we can pass it back to the legacy |
| // parser if we don't use it. |
| DateToken sign_token = scanner->Next(); |
| if (!scanner->Peek().IsFixedLengthNumber(6)) return sign_token; |
| int sign = sign_token.ascii_sign(); |
| int year = scanner->Next().number(); |
| if (sign < 0 && year == 0) return sign_token; |
| day->Add(sign * year); |
| } else if (scanner->Peek().IsFixedLengthNumber(4)) { |
| day->Add(scanner->Next().number()); |
| } else { |
| return scanner->Next(); |
| } |
| if (scanner->SkipSymbol('-')) { |
| if (!scanner->Peek().IsFixedLengthNumber(2) || |
| !DayComposer::IsMonth(scanner->Peek().number())) |
| return scanner->Next(); |
| day->Add(scanner->Next().number()); |
| if (scanner->SkipSymbol('-')) { |
| if (!scanner->Peek().IsFixedLengthNumber(2) || |
| !DayComposer::IsDay(scanner->Peek().number())) |
| return scanner->Next(); |
| day->Add(scanner->Next().number()); |
| } |
| } |
| // Check for optional time string: 'T'HH':'mm[':'ss['.'sss]]Z |
| if (!scanner->Peek().IsKeywordType(TIME_SEPARATOR)) { |
| if (!scanner->Peek().IsEndOfInput()) return scanner->Next(); |
| } else { |
| // ES5 Date Time String time part is present. |
| scanner->Next(); |
| if (!scanner->Peek().IsFixedLengthNumber(2) || |
| !Between(scanner->Peek().number(), 0, 24)) { |
| return DateToken::Invalid(); |
| } |
| // Allow 24:00[:00[.000]], but no other time starting with 24. |
| bool hour_is_24 = (scanner->Peek().number() == 24); |
| time->Add(scanner->Next().number()); |
| if (!scanner->SkipSymbol(':')) return DateToken::Invalid(); |
| if (!scanner->Peek().IsFixedLengthNumber(2) || |
| !TimeComposer::IsMinute(scanner->Peek().number()) || |
| (hour_is_24 && scanner->Peek().number() > 0)) { |
| return DateToken::Invalid(); |
| } |
| time->Add(scanner->Next().number()); |
| if (scanner->SkipSymbol(':')) { |
| if (!scanner->Peek().IsFixedLengthNumber(2) || |
| !TimeComposer::IsSecond(scanner->Peek().number()) || |
| (hour_is_24 && scanner->Peek().number() > 0)) { |
| return DateToken::Invalid(); |
| } |
| time->Add(scanner->Next().number()); |
| if (scanner->SkipSymbol('.')) { |
| if (!scanner->Peek().IsNumber() || |
| (hour_is_24 && scanner->Peek().number() > 0)) { |
| return DateToken::Invalid(); |
| } |
| // Allow more or less than the mandated three digits. |
| time->Add(ReadMilliseconds(scanner->Next())); |
| } |
| } |
| // Check for optional timezone designation: 'Z' | ('+'|'-')hh':'mm |
| if (scanner->Peek().IsKeywordZ()) { |
| scanner->Next(); |
| tz->Set(0); |
| } else if (scanner->Peek().IsSymbol('+') || scanner->Peek().IsSymbol('-')) { |
| tz->SetSign(scanner->Next().symbol() == '+' ? 1 : -1); |
| if (scanner->Peek().IsFixedLengthNumber(4)) { |
| // hhmm extension syntax. |
| int hourmin = scanner->Next().number(); |
| int hour = hourmin / 100; |
| int min = hourmin % 100; |
| if (!TimeComposer::IsHour(hour) || !TimeComposer::IsMinute(min)) { |
| return DateToken::Invalid(); |
| } |
| tz->SetAbsoluteHour(hour); |
| tz->SetAbsoluteMinute(min); |
| } else { |
| // hh:mm standard syntax. |
| if (!scanner->Peek().IsFixedLengthNumber(2) || |
| !TimeComposer::IsHour(scanner->Peek().number())) { |
| return DateToken::Invalid(); |
| } |
| tz->SetAbsoluteHour(scanner->Next().number()); |
| if (!scanner->SkipSymbol(':')) return DateToken::Invalid(); |
| if (!scanner->Peek().IsFixedLengthNumber(2) || |
| !TimeComposer::IsMinute(scanner->Peek().number())) { |
| return DateToken::Invalid(); |
| } |
| tz->SetAbsoluteMinute(scanner->Next().number()); |
| } |
| } |
| if (!scanner->Peek().IsEndOfInput()) return DateToken::Invalid(); |
| } |
| // Successfully parsed ES5 Date Time String. |
| // ES#sec-date-time-string-format Date Time String Format |
| // "When the time zone offset is absent, date-only forms are interpreted |
| // as a UTC time and date-time forms are interpreted as a local time." |
| if (tz->IsEmpty() && time->IsEmpty()) { |
| tz->Set(0); |
| } |
| day->set_iso_date(); |
| return DateToken::EndOfInput(); |
| } |
| |
| } // namespace internal |
| } // namespace v8 |
| |
| #endif // V8_DATE_DATEPARSER_INL_H_ |