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// 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, base::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 ms = ReadMilliseconds(scanner.Next());
if (ms < 0) return false;
time.AddFinal(ms);
} 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 next_token = scanner.Next();
length = next_token.length();
n = next_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() && !in_->IsWhiteSpaceChar()) {
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_