1 // Copyright 2011 the V8 project authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef V8_DATEPARSER_INL_H_ 6 #define V8_DATEPARSER_INL_H_ 7 8 #include "src/char-predicates-inl.h" 9 #include "src/dateparser.h" 10 #include "src/unicode-cache-inl.h" 11 12 namespace v8 { 13 namespace internal { 14 15 template <typename Char> 16 bool DateParser::Parse(Isolate* isolate, Vector<Char> str, FixedArray* out) { 17 UnicodeCache* unicode_cache = isolate->unicode_cache(); 18 DCHECK(out->length() >= OUTPUT_SIZE); 19 InputReader<Char> in(unicode_cache, str); 20 DateStringTokenizer<Char> scanner(&in); 21 TimeZoneComposer tz; 22 TimeComposer time; 23 DayComposer day; 24 25 // Specification: 26 // Accept ES5 ISO 8601 date-time-strings or legacy dates compatible 27 // with Safari. 28 // ES5 ISO 8601 dates: 29 // [('-'|'+')yy]yyyy[-MM[-DD]][THH:mm[:ss[.sss]][Z|(+|-)hh:mm]] 30 // where yyyy is in the range 0000..9999 and 31 // +/-yyyyyy is in the range -999999..+999999 - 32 // but -000000 is invalid (year zero must be positive), 33 // MM is in the range 01..12, 34 // DD is in the range 01..31, 35 // MM and DD defaults to 01 if missing,, 36 // HH is generally in the range 00..23, but can be 24 if mm, ss 37 // and sss are zero (or missing), representing midnight at the 38 // end of a day, 39 // mm and ss are in the range 00..59, 40 // sss is in the range 000..999, 41 // hh is in the range 00..23, 42 // mm, ss, and sss default to 00 if missing, and 43 // timezone defaults to Z if missing 44 // (following Safari, ISO actually demands local time). 45 // Extensions: 46 // We also allow sss to have more or less than three digits (but at 47 // least one). 48 // We allow hh:mm to be specified as hhmm. 49 // Legacy dates: 50 // Any unrecognized word before the first number is ignored. 51 // Parenthesized text is ignored. 52 // An unsigned number followed by ':' is a time value, and is 53 // added to the TimeComposer. A number followed by '::' adds a second 54 // zero as well. A number followed by '.' is also a time and must be 55 // followed by milliseconds. 56 // Any other number is a date component and is added to DayComposer. 57 // A month name (or really: any word having the same first three letters 58 // as a month name) is recorded as a named month in the Day composer. 59 // A word recognizable as a time-zone is recorded as such, as is 60 // '(+|-)(hhmm|hh:)'. 61 // Legacy dates don't allow extra signs ('+' or '-') or umatched ')' 62 // after a number has been read (before the first number, any garbage 63 // is allowed). 64 // Intersection of the two: 65 // A string that matches both formats (e.g. 1970-01-01) will be 66 // parsed as an ES5 date-time string - which means it will default 67 // to UTC time-zone. That's unavoidable if following the ES5 68 // specification. 69 // After a valid "T" has been read while scanning an ES5 datetime string, 70 // the input can no longer be a valid legacy date, since the "T" is a 71 // garbage string after a number has been read. 72 73 // First try getting as far as possible with as ES5 Date Time String. 74 DateToken next_unhandled_token = ParseES5DateTime(&scanner, &day, &time, &tz); 75 if (next_unhandled_token.IsInvalid()) return false; 76 bool has_read_number = !day.IsEmpty(); 77 // If there's anything left, continue with the legacy parser. 78 bool legacy_parser = false; 79 for (DateToken token = next_unhandled_token; 80 !token.IsEndOfInput(); 81 token = scanner.Next()) { 82 if (token.IsNumber()) { 83 legacy_parser = true; 84 has_read_number = true; 85 int n = token.number(); 86 if (scanner.SkipSymbol(':')) { 87 if (scanner.SkipSymbol(':')) { 88 // n + "::" 89 if (!time.IsEmpty()) return false; 90 time.Add(n); 91 time.Add(0); 92 } else { 93 // n + ":" 94 if (!time.Add(n)) return false; 95 if (scanner.Peek().IsSymbol('.')) scanner.Next(); 96 } 97 } else if (scanner.SkipSymbol('.') && time.IsExpecting(n)) { 98 time.Add(n); 99 if (!scanner.Peek().IsNumber()) return false; 100 int n = ReadMilliseconds(scanner.Next()); 101 if (n < 0) return false; 102 time.AddFinal(n); 103 } else if (tz.IsExpecting(n)) { 104 tz.SetAbsoluteMinute(n); 105 } else if (time.IsExpecting(n)) { 106 time.AddFinal(n); 107 // Require end, white space, "Z", "+" or "-" immediately after 108 // finalizing time. 109 DateToken peek = scanner.Peek(); 110 if (!peek.IsEndOfInput() && 111 !peek.IsWhiteSpace() && 112 !peek.IsKeywordZ() && 113 !peek.IsAsciiSign()) return false; 114 } else { 115 if (!day.Add(n)) return false; 116 scanner.SkipSymbol('-'); 117 } 118 } else if (token.IsKeyword()) { 119 legacy_parser = true; 120 // Parse a "word" (sequence of chars. >= 'A'). 121 KeywordType type = token.keyword_type(); 122 int value = token.keyword_value(); 123 if (type == AM_PM && !time.IsEmpty()) { 124 time.SetHourOffset(value); 125 } else if (type == MONTH_NAME) { 126 day.SetNamedMonth(value); 127 scanner.SkipSymbol('-'); 128 } else if (type == TIME_ZONE_NAME && has_read_number) { 129 tz.Set(value); 130 } else { 131 // Garbage words are illegal if a number has been read. 132 if (has_read_number) return false; 133 // The first number has to be separated from garbage words by 134 // whitespace or other separators. 135 if (scanner.Peek().IsNumber()) return false; 136 } 137 } else if (token.IsAsciiSign() && (tz.IsUTC() || !time.IsEmpty())) { 138 legacy_parser = true; 139 // Parse UTC offset (only after UTC or time). 140 tz.SetSign(token.ascii_sign()); 141 // The following number may be empty. 142 int n = 0; 143 int length = 0; 144 if (scanner.Peek().IsNumber()) { 145 DateToken token = scanner.Next(); 146 length = token.length(); 147 n = token.number(); 148 } 149 has_read_number = true; 150 151 if (scanner.Peek().IsSymbol(':')) { 152 tz.SetAbsoluteHour(n); 153 // TODO(littledan): Use minutes as part of timezone? 154 tz.SetAbsoluteMinute(kNone); 155 } else if (length == 2 || length == 1) { 156 // Handle time zones like GMT-8 157 tz.SetAbsoluteHour(n); 158 tz.SetAbsoluteMinute(0); 159 } else if (length == 4 || length == 3) { 160 // Looks like the hhmm format 161 tz.SetAbsoluteHour(n / 100); 162 tz.SetAbsoluteMinute(n % 100); 163 } else { 164 // No need to accept time zones like GMT-12345 165 return false; 166 } 167 } else if ((token.IsAsciiSign() || token.IsSymbol(')')) && 168 has_read_number) { 169 // Extra sign or ')' is illegal if a number has been read. 170 return false; 171 } else { 172 // Ignore other characters and whitespace. 173 } 174 } 175 176 bool success = day.Write(out) && time.Write(out) && tz.Write(out); 177 178 if (legacy_parser && success) { 179 isolate->CountUsage(v8::Isolate::kLegacyDateParser); 180 } 181 182 return success; 183 } 184 185 186 template<typename CharType> 187 DateParser::DateToken DateParser::DateStringTokenizer<CharType>::Scan() { 188 int pre_pos = in_->position(); 189 if (in_->IsEnd()) return DateToken::EndOfInput(); 190 if (in_->IsAsciiDigit()) { 191 int n = in_->ReadUnsignedNumeral(); 192 int length = in_->position() - pre_pos; 193 return DateToken::Number(n, length); 194 } 195 if (in_->Skip(':')) return DateToken::Symbol(':'); 196 if (in_->Skip('-')) return DateToken::Symbol('-'); 197 if (in_->Skip('+')) return DateToken::Symbol('+'); 198 if (in_->Skip('.')) return DateToken::Symbol('.'); 199 if (in_->Skip(')')) return DateToken::Symbol(')'); 200 if (in_->IsAsciiAlphaOrAbove()) { 201 DCHECK(KeywordTable::kPrefixLength == 3); 202 uint32_t buffer[3] = {0, 0, 0}; 203 int length = in_->ReadWord(buffer, 3); 204 int index = KeywordTable::Lookup(buffer, length); 205 return DateToken::Keyword(KeywordTable::GetType(index), 206 KeywordTable::GetValue(index), 207 length); 208 } 209 if (in_->SkipWhiteSpace()) { 210 return DateToken::WhiteSpace(in_->position() - pre_pos); 211 } 212 if (in_->SkipParentheses()) { 213 return DateToken::Unknown(); 214 } 215 in_->Next(); 216 return DateToken::Unknown(); 217 } 218 219 220 template <typename Char> 221 bool DateParser::InputReader<Char>::SkipWhiteSpace() { 222 if (unicode_cache_->IsWhiteSpaceOrLineTerminator(ch_)) { 223 Next(); 224 return true; 225 } 226 return false; 227 } 228 229 230 template <typename Char> 231 bool DateParser::InputReader<Char>::SkipParentheses() { 232 if (ch_ != '(') return false; 233 int balance = 0; 234 do { 235 if (ch_ == ')') --balance; 236 else if (ch_ == '(') ++balance; 237 Next(); 238 } while (balance > 0 && ch_); 239 return true; 240 } 241 242 243 template <typename Char> 244 DateParser::DateToken DateParser::ParseES5DateTime( 245 DateStringTokenizer<Char>* scanner, DayComposer* day, TimeComposer* time, 246 TimeZoneComposer* tz) { 247 DCHECK(day->IsEmpty()); 248 DCHECK(time->IsEmpty()); 249 DCHECK(tz->IsEmpty()); 250 251 // Parse mandatory date string: [('-'|'+')yy]yyyy[':'MM[':'DD]] 252 if (scanner->Peek().IsAsciiSign()) { 253 // Keep the sign token, so we can pass it back to the legacy 254 // parser if we don't use it. 255 DateToken sign_token = scanner->Next(); 256 if (!scanner->Peek().IsFixedLengthNumber(6)) return sign_token; 257 int sign = sign_token.ascii_sign(); 258 int year = scanner->Next().number(); 259 if (sign < 0 && year == 0) return sign_token; 260 day->Add(sign * year); 261 } else if (scanner->Peek().IsFixedLengthNumber(4)) { 262 day->Add(scanner->Next().number()); 263 } else { 264 return scanner->Next(); 265 } 266 if (scanner->SkipSymbol('-')) { 267 if (!scanner->Peek().IsFixedLengthNumber(2) || 268 !DayComposer::IsMonth(scanner->Peek().number())) return scanner->Next(); 269 day->Add(scanner->Next().number()); 270 if (scanner->SkipSymbol('-')) { 271 if (!scanner->Peek().IsFixedLengthNumber(2) || 272 !DayComposer::IsDay(scanner->Peek().number())) return scanner->Next(); 273 day->Add(scanner->Next().number()); 274 } 275 } 276 // Check for optional time string: 'T'HH':'mm[':'ss['.'sss]]Z 277 if (!scanner->Peek().IsKeywordType(TIME_SEPARATOR)) { 278 if (!scanner->Peek().IsEndOfInput()) return scanner->Next(); 279 } else { 280 // ES5 Date Time String time part is present. 281 scanner->Next(); 282 if (!scanner->Peek().IsFixedLengthNumber(2) || 283 !Between(scanner->Peek().number(), 0, 24)) { 284 return DateToken::Invalid(); 285 } 286 // Allow 24:00[:00[.000]], but no other time starting with 24. 287 bool hour_is_24 = (scanner->Peek().number() == 24); 288 time->Add(scanner->Next().number()); 289 if (!scanner->SkipSymbol(':')) return DateToken::Invalid(); 290 if (!scanner->Peek().IsFixedLengthNumber(2) || 291 !TimeComposer::IsMinute(scanner->Peek().number()) || 292 (hour_is_24 && scanner->Peek().number() > 0)) { 293 return DateToken::Invalid(); 294 } 295 time->Add(scanner->Next().number()); 296 if (scanner->SkipSymbol(':')) { 297 if (!scanner->Peek().IsFixedLengthNumber(2) || 298 !TimeComposer::IsSecond(scanner->Peek().number()) || 299 (hour_is_24 && scanner->Peek().number() > 0)) { 300 return DateToken::Invalid(); 301 } 302 time->Add(scanner->Next().number()); 303 if (scanner->SkipSymbol('.')) { 304 if (!scanner->Peek().IsNumber() || 305 (hour_is_24 && scanner->Peek().number() > 0)) { 306 return DateToken::Invalid(); 307 } 308 // Allow more or less than the mandated three digits. 309 time->Add(ReadMilliseconds(scanner->Next())); 310 } 311 } 312 // Check for optional timezone designation: 'Z' | ('+'|'-')hh':'mm 313 if (scanner->Peek().IsKeywordZ()) { 314 scanner->Next(); 315 tz->Set(0); 316 } else if (scanner->Peek().IsSymbol('+') || 317 scanner->Peek().IsSymbol('-')) { 318 tz->SetSign(scanner->Next().symbol() == '+' ? 1 : -1); 319 if (scanner->Peek().IsFixedLengthNumber(4)) { 320 // hhmm extension syntax. 321 int hourmin = scanner->Next().number(); 322 int hour = hourmin / 100; 323 int min = hourmin % 100; 324 if (!TimeComposer::IsHour(hour) || !TimeComposer::IsMinute(min)) { 325 return DateToken::Invalid(); 326 } 327 tz->SetAbsoluteHour(hour); 328 tz->SetAbsoluteMinute(min); 329 } else { 330 // hh:mm standard syntax. 331 if (!scanner->Peek().IsFixedLengthNumber(2) || 332 !TimeComposer::IsHour(scanner->Peek().number())) { 333 return DateToken::Invalid(); 334 } 335 tz->SetAbsoluteHour(scanner->Next().number()); 336 if (!scanner->SkipSymbol(':')) return DateToken::Invalid(); 337 if (!scanner->Peek().IsFixedLengthNumber(2) || 338 !TimeComposer::IsMinute(scanner->Peek().number())) { 339 return DateToken::Invalid(); 340 } 341 tz->SetAbsoluteMinute(scanner->Next().number()); 342 } 343 } 344 if (!scanner->Peek().IsEndOfInput()) return DateToken::Invalid(); 345 } 346 // Successfully parsed ES5 Date Time String. 347 // ES#sec-date-time-string-format Date Time String Format 348 // "When the time zone offset is absent, date-only forms are interpreted 349 // as a UTC time and date-time forms are interpreted as a local time." 350 if (tz->IsEmpty() && time->IsEmpty()) { 351 tz->Set(0); 352 } 353 day->set_iso_date(); 354 return DateToken::EndOfInput(); 355 } 356 357 358 } // namespace internal 359 } // namespace v8 360 361 #endif // V8_DATEPARSER_INL_H_ 362
