1/* 2 * Copyright (C) 1999-2002 Harri Porten (porten@kde.org) 3 * Copyright (C) 2001 Peter Kelly (pmk@post.com) 4 * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2012 Apple Inc. All rights reserved. 5 * Copyright (C) 2007 Cameron Zwarich (cwzwarich@uwaterloo.ca) 6 * Copyright (C) 2007 Maks Orlovich 7 * 8 * This library is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU Library General Public 10 * License as published by the Free Software Foundation; either 11 * version 2 of the License, or (at your option) any later version. 12 * 13 * This library is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 16 * Library General Public License for more details. 17 * 18 * You should have received a copy of the GNU Library General Public License 19 * along with this library; see the file COPYING.LIB. If not, write to 20 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 21 * Boston, MA 02110-1301, USA. 22 * 23 */ 24 25#include "config.h" 26#include "JSGlobalObjectFunctions.h" 27 28#include "CallFrame.h" 29#include "Interpreter.h" 30#include "JSFunction.h" 31#include "JSGlobalObject.h" 32#include "JSString.h" 33#include "JSStringBuilder.h" 34#include "Lexer.h" 35#include "LiteralParser.h" 36#include "Nodes.h" 37#include "Operations.h" 38#include "Parser.h" 39#include <wtf/dtoa.h> 40#include <stdio.h> 41#include <stdlib.h> 42#include <wtf/ASCIICType.h> 43#include <wtf/Assertions.h> 44#include <wtf/MathExtras.h> 45#include <wtf/StringExtras.h> 46#include <wtf/text/StringBuilder.h> 47#include <wtf/unicode/UTF8.h> 48 49using namespace WTF; 50using namespace Unicode; 51 52namespace JSC { 53 54static JSValue encode(ExecState* exec, const char* doNotEscape) 55{ 56 CString cstr = exec->argument(0).toString(exec)->value(exec).utf8(String::StrictConversion); 57 if (!cstr.data()) 58 return throwError(exec, createURIError(exec, ASCIILiteral("String contained an illegal UTF-16 sequence."))); 59 60 JSStringBuilder builder; 61 const char* p = cstr.data(); 62 for (size_t k = 0; k < cstr.length(); k++, p++) { 63 char c = *p; 64 if (c && strchr(doNotEscape, c)) 65 builder.append(c); 66 else { 67 char tmp[4]; 68 snprintf(tmp, sizeof(tmp), "%%%02X", static_cast<unsigned char>(c)); 69 builder.append(tmp); 70 } 71 } 72 return builder.build(exec); 73} 74 75template <typename CharType> 76ALWAYS_INLINE 77static JSValue decode(ExecState* exec, const CharType* characters, int length, const char* doNotUnescape, bool strict) 78{ 79 JSStringBuilder builder; 80 int k = 0; 81 UChar u = 0; 82 while (k < length) { 83 const CharType* p = characters + k; 84 CharType c = *p; 85 if (c == '%') { 86 int charLen = 0; 87 if (k <= length - 3 && isASCIIHexDigit(p[1]) && isASCIIHexDigit(p[2])) { 88 const char b0 = Lexer<CharType>::convertHex(p[1], p[2]); 89 const int sequenceLen = UTF8SequenceLength(b0); 90 if (sequenceLen && k <= length - sequenceLen * 3) { 91 charLen = sequenceLen * 3; 92 char sequence[5]; 93 sequence[0] = b0; 94 for (int i = 1; i < sequenceLen; ++i) { 95 const CharType* q = p + i * 3; 96 if (q[0] == '%' && isASCIIHexDigit(q[1]) && isASCIIHexDigit(q[2])) 97 sequence[i] = Lexer<CharType>::convertHex(q[1], q[2]); 98 else { 99 charLen = 0; 100 break; 101 } 102 } 103 if (charLen != 0) { 104 sequence[sequenceLen] = 0; 105 const int character = decodeUTF8Sequence(sequence); 106 if (character < 0 || character >= 0x110000) 107 charLen = 0; 108 else if (character >= 0x10000) { 109 // Convert to surrogate pair. 110 builder.append(static_cast<UChar>(0xD800 | ((character - 0x10000) >> 10))); 111 u = static_cast<UChar>(0xDC00 | ((character - 0x10000) & 0x3FF)); 112 } else 113 u = static_cast<UChar>(character); 114 } 115 } 116 } 117 if (charLen == 0) { 118 if (strict) 119 return throwError(exec, createURIError(exec, ASCIILiteral("URI error"))); 120 // The only case where we don't use "strict" mode is the "unescape" function. 121 // For that, it's good to support the wonky "%u" syntax for compatibility with WinIE. 122 if (k <= length - 6 && p[1] == 'u' 123 && isASCIIHexDigit(p[2]) && isASCIIHexDigit(p[3]) 124 && isASCIIHexDigit(p[4]) && isASCIIHexDigit(p[5])) { 125 charLen = 6; 126 u = Lexer<UChar>::convertUnicode(p[2], p[3], p[4], p[5]); 127 } 128 } 129 if (charLen && (u == 0 || u >= 128 || !strchr(doNotUnescape, u))) { 130 if (u < 256) 131 builder.append(static_cast<LChar>(u)); 132 else 133 builder.append(u); 134 k += charLen; 135 continue; 136 } 137 } 138 k++; 139 builder.append(c); 140 } 141 return builder.build(exec); 142} 143 144static JSValue decode(ExecState* exec, const char* doNotUnescape, bool strict) 145{ 146 JSStringBuilder builder; 147 String str = exec->argument(0).toString(exec)->value(exec); 148 149 if (str.is8Bit()) 150 return decode(exec, str.characters8(), str.length(), doNotUnescape, strict); 151 return decode(exec, str.characters16(), str.length(), doNotUnescape, strict); 152} 153 154bool isStrWhiteSpace(UChar c) 155{ 156 switch (c) { 157 // ECMA-262-5th 7.2 & 7.3 158 case 0x0009: 159 case 0x000A: 160 case 0x000B: 161 case 0x000C: 162 case 0x000D: 163 case 0x0020: 164 case 0x00A0: 165 case 0x2028: 166 case 0x2029: 167 case 0xFEFF: 168 return true; 169 default: 170 return c > 0xff && isSeparatorSpace(c); 171 } 172} 173 174static int parseDigit(unsigned short c, int radix) 175{ 176 int digit = -1; 177 178 if (c >= '0' && c <= '9') 179 digit = c - '0'; 180 else if (c >= 'A' && c <= 'Z') 181 digit = c - 'A' + 10; 182 else if (c >= 'a' && c <= 'z') 183 digit = c - 'a' + 10; 184 185 if (digit >= radix) 186 return -1; 187 return digit; 188} 189 190double parseIntOverflow(const LChar* s, int length, int radix) 191{ 192 double number = 0.0; 193 double radixMultiplier = 1.0; 194 195 for (const LChar* p = s + length - 1; p >= s; p--) { 196 if (radixMultiplier == std::numeric_limits<double>::infinity()) { 197 if (*p != '0') { 198 number = std::numeric_limits<double>::infinity(); 199 break; 200 } 201 } else { 202 int digit = parseDigit(*p, radix); 203 number += digit * radixMultiplier; 204 } 205 206 radixMultiplier *= radix; 207 } 208 209 return number; 210} 211 212double parseIntOverflow(const UChar* s, int length, int radix) 213{ 214 double number = 0.0; 215 double radixMultiplier = 1.0; 216 217 for (const UChar* p = s + length - 1; p >= s; p--) { 218 if (radixMultiplier == std::numeric_limits<double>::infinity()) { 219 if (*p != '0') { 220 number = std::numeric_limits<double>::infinity(); 221 break; 222 } 223 } else { 224 int digit = parseDigit(*p, radix); 225 number += digit * radixMultiplier; 226 } 227 228 radixMultiplier *= radix; 229 } 230 231 return number; 232} 233 234// ES5.1 15.1.2.2 235template <typename CharType> 236ALWAYS_INLINE 237static double parseInt(const String& s, const CharType* data, int radix) 238{ 239 // 1. Let inputString be ToString(string). 240 // 2. Let S be a newly created substring of inputString consisting of the first character that is not a 241 // StrWhiteSpaceChar and all characters following that character. (In other words, remove leading white 242 // space.) If inputString does not contain any such characters, let S be the empty string. 243 int length = s.length(); 244 int p = 0; 245 while (p < length && isStrWhiteSpace(data[p])) 246 ++p; 247 248 // 3. Let sign be 1. 249 // 4. If S is not empty and the first character of S is a minus sign -, let sign be -1. 250 // 5. If S is not empty and the first character of S is a plus sign + or a minus sign -, then remove the first character from S. 251 double sign = 1; 252 if (p < length) { 253 if (data[p] == '+') 254 ++p; 255 else if (data[p] == '-') { 256 sign = -1; 257 ++p; 258 } 259 } 260 261 // 6. Let R = ToInt32(radix). 262 // 7. Let stripPrefix be true. 263 // 8. If R != 0,then 264 // b. If R != 16, let stripPrefix be false. 265 // 9. Else, R == 0 266 // a. LetR = 10. 267 // 10. If stripPrefix is true, then 268 // a. If the length of S is at least 2 and the first two characters of S are either ―0x or ―0X, 269 // then remove the first two characters from S and let R = 16. 270 // 11. If S contains any character that is not a radix-R digit, then let Z be the substring of S 271 // consisting of all characters before the first such character; otherwise, let Z be S. 272 if ((radix == 0 || radix == 16) && length - p >= 2 && data[p] == '0' && (data[p + 1] == 'x' || data[p + 1] == 'X')) { 273 radix = 16; 274 p += 2; 275 } else if (radix == 0) 276 radix = 10; 277 278 // 8.a If R < 2 or R > 36, then return NaN. 279 if (radix < 2 || radix > 36) 280 return QNaN; 281 282 // 13. Let mathInt be the mathematical integer value that is represented by Z in radix-R notation, using the letters 283 // A-Z and a-z for digits with values 10 through 35. (However, if R is 10 and Z contains more than 20 significant 284 // digits, every significant digit after the 20th may be replaced by a 0 digit, at the option of the implementation; 285 // and if R is not 2, 4, 8, 10, 16, or 32, then mathInt may be an implementation-dependent approximation to the 286 // mathematical integer value that is represented by Z in radix-R notation.) 287 // 14. Let number be the Number value for mathInt. 288 int firstDigitPosition = p; 289 bool sawDigit = false; 290 double number = 0; 291 while (p < length) { 292 int digit = parseDigit(data[p], radix); 293 if (digit == -1) 294 break; 295 sawDigit = true; 296 number *= radix; 297 number += digit; 298 ++p; 299 } 300 301 // 12. If Z is empty, return NaN. 302 if (!sawDigit) 303 return QNaN; 304 305 // Alternate code path for certain large numbers. 306 if (number >= mantissaOverflowLowerBound) { 307 if (radix == 10) { 308 size_t parsedLength; 309 number = parseDouble(s.characters() + firstDigitPosition, p - firstDigitPosition, parsedLength); 310 } else if (radix == 2 || radix == 4 || radix == 8 || radix == 16 || radix == 32) 311 number = parseIntOverflow(s.substringSharingImpl(firstDigitPosition, p - firstDigitPosition).utf8().data(), p - firstDigitPosition, radix); 312 } 313 314 // 15. Return sign x number. 315 return sign * number; 316} 317 318static double parseInt(const String& s, int radix) 319{ 320 if (s.is8Bit()) 321 return parseInt(s, s.characters8(), radix); 322 return parseInt(s, s.characters16(), radix); 323} 324 325static const int SizeOfInfinity = 8; 326 327template <typename CharType> 328static bool isInfinity(const CharType* data, const CharType* end) 329{ 330 return (end - data) >= SizeOfInfinity 331 && data[0] == 'I' 332 && data[1] == 'n' 333 && data[2] == 'f' 334 && data[3] == 'i' 335 && data[4] == 'n' 336 && data[5] == 'i' 337 && data[6] == 't' 338 && data[7] == 'y'; 339} 340 341// See ecma-262 9.3.1 342template <typename CharType> 343static double jsHexIntegerLiteral(const CharType*& data, const CharType* end) 344{ 345 // Hex number. 346 data += 2; 347 const CharType* firstDigitPosition = data; 348 double number = 0; 349 while (true) { 350 number = number * 16 + toASCIIHexValue(*data); 351 ++data; 352 if (data == end) 353 break; 354 if (!isASCIIHexDigit(*data)) 355 break; 356 } 357 if (number >= mantissaOverflowLowerBound) 358 number = parseIntOverflow(firstDigitPosition, data - firstDigitPosition, 16); 359 360 return number; 361} 362 363// See ecma-262 9.3.1 364template <typename CharType> 365static double jsStrDecimalLiteral(const CharType*& data, const CharType* end) 366{ 367 RELEASE_ASSERT(data < end); 368 369 size_t parsedLength; 370 double number = parseDouble(data, end - data, parsedLength); 371 if (parsedLength) { 372 data += parsedLength; 373 return number; 374 } 375 376 // Check for [+-]?Infinity 377 switch (*data) { 378 case 'I': 379 if (isInfinity(data, end)) { 380 data += SizeOfInfinity; 381 return std::numeric_limits<double>::infinity(); 382 } 383 break; 384 385 case '+': 386 if (isInfinity(data + 1, end)) { 387 data += SizeOfInfinity + 1; 388 return std::numeric_limits<double>::infinity(); 389 } 390 break; 391 392 case '-': 393 if (isInfinity(data + 1, end)) { 394 data += SizeOfInfinity + 1; 395 return -std::numeric_limits<double>::infinity(); 396 } 397 break; 398 } 399 400 // Not a number. 401 return QNaN; 402} 403 404template <typename CharType> 405static double toDouble(const CharType* characters, unsigned size) 406{ 407 const CharType* endCharacters = characters + size; 408 409 // Skip leading white space. 410 for (; characters < endCharacters; ++characters) { 411 if (!isStrWhiteSpace(*characters)) 412 break; 413 } 414 415 // Empty string. 416 if (characters == endCharacters) 417 return 0.0; 418 419 double number; 420 if (characters[0] == '0' && characters + 2 < endCharacters && (characters[1] | 0x20) == 'x' && isASCIIHexDigit(characters[2])) 421 number = jsHexIntegerLiteral(characters, endCharacters); 422 else 423 number = jsStrDecimalLiteral(characters, endCharacters); 424 425 // Allow trailing white space. 426 for (; characters < endCharacters; ++characters) { 427 if (!isStrWhiteSpace(*characters)) 428 break; 429 } 430 if (characters != endCharacters) 431 return QNaN; 432 433 return number; 434} 435 436// See ecma-262 9.3.1 437double jsToNumber(const String& s) 438{ 439 unsigned size = s.length(); 440 441 if (size == 1) { 442 UChar c = s[0]; 443 if (isASCIIDigit(c)) 444 return c - '0'; 445 if (isStrWhiteSpace(c)) 446 return 0; 447 return QNaN; 448 } 449 450 if (s.is8Bit()) 451 return toDouble(s.characters8(), size); 452 return toDouble(s.characters16(), size); 453} 454 455static double parseFloat(const String& s) 456{ 457 unsigned size = s.length(); 458 459 if (size == 1) { 460 UChar c = s[0]; 461 if (isASCIIDigit(c)) 462 return c - '0'; 463 return QNaN; 464 } 465 466 if (s.is8Bit()) { 467 const LChar* data = s.characters8(); 468 const LChar* end = data + size; 469 470 // Skip leading white space. 471 for (; data < end; ++data) { 472 if (!isStrWhiteSpace(*data)) 473 break; 474 } 475 476 // Empty string. 477 if (data == end) 478 return QNaN; 479 480 return jsStrDecimalLiteral(data, end); 481 } 482 483 const UChar* data = s.characters16(); 484 const UChar* end = data + size; 485 486 // Skip leading white space. 487 for (; data < end; ++data) { 488 if (!isStrWhiteSpace(*data)) 489 break; 490 } 491 492 // Empty string. 493 if (data == end) 494 return QNaN; 495 496 return jsStrDecimalLiteral(data, end); 497} 498 499EncodedJSValue JSC_HOST_CALL globalFuncEval(ExecState* exec) 500{ 501 JSValue x = exec->argument(0); 502 if (!x.isString()) 503 return JSValue::encode(x); 504 505 String s = x.toString(exec)->value(exec); 506 507 if (s.is8Bit()) { 508 LiteralParser<LChar> preparser(exec, s.characters8(), s.length(), NonStrictJSON); 509 if (JSValue parsedObject = preparser.tryLiteralParse()) 510 return JSValue::encode(parsedObject); 511 } else { 512 LiteralParser<UChar> preparser(exec, s.characters16(), s.length(), NonStrictJSON); 513 if (JSValue parsedObject = preparser.tryLiteralParse()) 514 return JSValue::encode(parsedObject); 515 } 516 517 JSGlobalObject* calleeGlobalObject = exec->callee()->globalObject(); 518 EvalExecutable* eval = EvalExecutable::create(exec, exec->vm().codeCache(), makeSource(s), false); 519 JSObject* error = eval->compile(exec, calleeGlobalObject); 520 if (error) 521 return throwVMError(exec, error); 522 523 return JSValue::encode(exec->interpreter()->execute(eval, exec, calleeGlobalObject->globalThis(), calleeGlobalObject)); 524} 525 526EncodedJSValue JSC_HOST_CALL globalFuncParseInt(ExecState* exec) 527{ 528 JSValue value = exec->argument(0); 529 JSValue radixValue = exec->argument(1); 530 531 // Optimized handling for numbers: 532 // If the argument is 0 or a number in range 10^-6 <= n < INT_MAX+1, then parseInt 533 // results in a truncation to integer. In the case of -0, this is converted to 0. 534 // 535 // This is also a truncation for values in the range INT_MAX+1 <= n < 10^21, 536 // however these values cannot be trivially truncated to int since 10^21 exceeds 537 // even the int64_t range. Negative numbers are a little trickier, the case for 538 // values in the range -10^21 < n <= -1 are similar to those for integer, but 539 // values in the range -1 < n <= -10^-6 need to truncate to -0, not 0. 540 static const double tenToTheMinus6 = 0.000001; 541 static const double intMaxPlusOne = 2147483648.0; 542 if (value.isNumber()) { 543 double n = value.asNumber(); 544 if (((n < intMaxPlusOne && n >= tenToTheMinus6) || !n) && radixValue.isUndefinedOrNull()) 545 return JSValue::encode(jsNumber(static_cast<int32_t>(n))); 546 } 547 548 // If ToString throws, we shouldn't call ToInt32. 549 String s = value.toString(exec)->value(exec); 550 if (exec->hadException()) 551 return JSValue::encode(jsUndefined()); 552 553 return JSValue::encode(jsNumber(parseInt(s, radixValue.toInt32(exec)))); 554} 555 556EncodedJSValue JSC_HOST_CALL globalFuncParseFloat(ExecState* exec) 557{ 558 return JSValue::encode(jsNumber(parseFloat(exec->argument(0).toString(exec)->value(exec)))); 559} 560 561EncodedJSValue JSC_HOST_CALL globalFuncIsNaN(ExecState* exec) 562{ 563 return JSValue::encode(jsBoolean(std::isnan(exec->argument(0).toNumber(exec)))); 564} 565 566EncodedJSValue JSC_HOST_CALL globalFuncIsFinite(ExecState* exec) 567{ 568 double n = exec->argument(0).toNumber(exec); 569 return JSValue::encode(jsBoolean(std::isfinite(n))); 570} 571 572EncodedJSValue JSC_HOST_CALL globalFuncDecodeURI(ExecState* exec) 573{ 574 static const char do_not_unescape_when_decoding_URI[] = 575 "#$&+,/:;=?@"; 576 577 return JSValue::encode(decode(exec, do_not_unescape_when_decoding_URI, true)); 578} 579 580EncodedJSValue JSC_HOST_CALL globalFuncDecodeURIComponent(ExecState* exec) 581{ 582 return JSValue::encode(decode(exec, "", true)); 583} 584 585EncodedJSValue JSC_HOST_CALL globalFuncEncodeURI(ExecState* exec) 586{ 587 static const char do_not_escape_when_encoding_URI[] = 588 "ABCDEFGHIJKLMNOPQRSTUVWXYZ" 589 "abcdefghijklmnopqrstuvwxyz" 590 "0123456789" 591 "!#$&'()*+,-./:;=?@_~"; 592 593 return JSValue::encode(encode(exec, do_not_escape_when_encoding_URI)); 594} 595 596EncodedJSValue JSC_HOST_CALL globalFuncEncodeURIComponent(ExecState* exec) 597{ 598 static const char do_not_escape_when_encoding_URI_component[] = 599 "ABCDEFGHIJKLMNOPQRSTUVWXYZ" 600 "abcdefghijklmnopqrstuvwxyz" 601 "0123456789" 602 "!'()*-._~"; 603 604 return JSValue::encode(encode(exec, do_not_escape_when_encoding_URI_component)); 605} 606 607EncodedJSValue JSC_HOST_CALL globalFuncEscape(ExecState* exec) 608{ 609 static const char do_not_escape[] = 610 "ABCDEFGHIJKLMNOPQRSTUVWXYZ" 611 "abcdefghijklmnopqrstuvwxyz" 612 "0123456789" 613 "*+-./@_"; 614 615 JSStringBuilder builder; 616 String str = exec->argument(0).toString(exec)->value(exec); 617 if (str.is8Bit()) { 618 const LChar* c = str.characters8(); 619 for (unsigned k = 0; k < str.length(); k++, c++) { 620 int u = c[0]; 621 if (u && strchr(do_not_escape, static_cast<char>(u))) 622 builder.append(c, 1); 623 else { 624 char tmp[4]; 625 snprintf(tmp, sizeof(tmp), "%%%02X", u); 626 builder.append(tmp); 627 } 628 } 629 630 return JSValue::encode(builder.build(exec)); 631 } 632 633 const UChar* c = str.characters16(); 634 for (unsigned k = 0; k < str.length(); k++, c++) { 635 int u = c[0]; 636 if (u > 255) { 637 char tmp[7]; 638 snprintf(tmp, sizeof(tmp), "%%u%04X", u); 639 builder.append(tmp); 640 } else if (u != 0 && strchr(do_not_escape, static_cast<char>(u))) 641 builder.append(c, 1); 642 else { 643 char tmp[4]; 644 snprintf(tmp, sizeof(tmp), "%%%02X", u); 645 builder.append(tmp); 646 } 647 } 648 649 return JSValue::encode(builder.build(exec)); 650} 651 652EncodedJSValue JSC_HOST_CALL globalFuncUnescape(ExecState* exec) 653{ 654 StringBuilder builder; 655 String str = exec->argument(0).toString(exec)->value(exec); 656 int k = 0; 657 int len = str.length(); 658 659 if (str.is8Bit()) { 660 const LChar* characters = str.characters8(); 661 LChar convertedLChar; 662 while (k < len) { 663 const LChar* c = characters + k; 664 if (c[0] == '%' && k <= len - 6 && c[1] == 'u') { 665 if (isASCIIHexDigit(c[2]) && isASCIIHexDigit(c[3]) && isASCIIHexDigit(c[4]) && isASCIIHexDigit(c[5])) { 666 builder.append(Lexer<UChar>::convertUnicode(c[2], c[3], c[4], c[5])); 667 k += 6; 668 continue; 669 } 670 } else if (c[0] == '%' && k <= len - 3 && isASCIIHexDigit(c[1]) && isASCIIHexDigit(c[2])) { 671 convertedLChar = LChar(Lexer<LChar>::convertHex(c[1], c[2])); 672 c = &convertedLChar; 673 k += 2; 674 } 675 builder.append(*c); 676 k++; 677 } 678 } else { 679 const UChar* characters = str.characters16(); 680 681 while (k < len) { 682 const UChar* c = characters + k; 683 UChar convertedUChar; 684 if (c[0] == '%' && k <= len - 6 && c[1] == 'u') { 685 if (isASCIIHexDigit(c[2]) && isASCIIHexDigit(c[3]) && isASCIIHexDigit(c[4]) && isASCIIHexDigit(c[5])) { 686 convertedUChar = Lexer<UChar>::convertUnicode(c[2], c[3], c[4], c[5]); 687 c = &convertedUChar; 688 k += 5; 689 } 690 } else if (c[0] == '%' && k <= len - 3 && isASCIIHexDigit(c[1]) && isASCIIHexDigit(c[2])) { 691 convertedUChar = UChar(Lexer<UChar>::convertHex(c[1], c[2])); 692 c = &convertedUChar; 693 k += 2; 694 } 695 k++; 696 builder.append(*c); 697 } 698 } 699 700 return JSValue::encode(jsString(exec, builder.toString())); 701} 702 703EncodedJSValue JSC_HOST_CALL globalFuncThrowTypeError(ExecState* exec) 704{ 705 return throwVMTypeError(exec); 706} 707 708EncodedJSValue JSC_HOST_CALL globalFuncProtoGetter(ExecState* exec) 709{ 710 if (!exec->thisValue().isObject()) 711 return JSValue::encode(exec->thisValue().synthesizePrototype(exec)); 712 713 JSObject* thisObject = asObject(exec->thisValue()); 714 if (!thisObject->allowsAccessFrom(exec->trueCallerFrame())) 715 return JSValue::encode(jsUndefined()); 716 717 return JSValue::encode(thisObject->prototype()); 718} 719 720EncodedJSValue JSC_HOST_CALL globalFuncProtoSetter(ExecState* exec) 721{ 722 JSValue value = exec->argument(0); 723 724 // Setting __proto__ of a primitive should have no effect. 725 if (!exec->thisValue().isObject()) 726 return JSValue::encode(jsUndefined()); 727 728 JSObject* thisObject = asObject(exec->thisValue()); 729 if (!thisObject->allowsAccessFrom(exec->trueCallerFrame())) 730 return JSValue::encode(jsUndefined()); 731 732 // Setting __proto__ to a non-object, non-null value is silently ignored to match Mozilla. 733 if (!value.isObject() && !value.isNull()) 734 return JSValue::encode(jsUndefined()); 735 736 if (!thisObject->isExtensible()) 737 return throwVMError(exec, createTypeError(exec, StrictModeReadonlyPropertyWriteError)); 738 739 if (!thisObject->setPrototypeWithCycleCheck(exec->vm(), value)) 740 throwError(exec, createError(exec, "cyclic __proto__ value")); 741 return JSValue::encode(jsUndefined()); 742} 743 744} // namespace JSC 745