runtime/JSGlobalObjectFunctions.cpp

   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 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 "JSGlobalObject.h"
  31 #include "JSString.h"
  32 #include "JSStringBuilder.h"
  33 #include "Lexer.h"
  34 #include "LiteralParser.h"
  35 #include "Nodes.h"
  36 #include "Parser.h"
  37 #include "UStringBuilder.h"
  38 #include "dtoa.h"
  39 #include <stdio.h>
  40 #include <stdlib.h>
  41 #include <wtf/ASCIICType.h>
  42 #include <wtf/Assertions.h>
  43 #include <wtf/MathExtras.h>
  44 #include <wtf/StringExtras.h>
  45 #include <wtf/unicode/UTF8.h>
  46
  47 using namespace WTF;
  48 using namespace Unicode;
  49
  50 namespace JSC {
  51
  52 static JSValue encode(ExecState* exec, const char* doNotEscape)
  53 {
  54     UString str = exec->argument(0).toString(exec);
  55     CString cstr = str.utf8(true);
  56     if (!cstr.data())
  57         return throwError(exec, createURIError(exec, "String contained an illegal UTF-16 sequence."));
  58
  59     JSStringBuilder builder;
  60     const char* p = cstr.data();
  61     for (size_t k = 0; k < cstr.length(); k++, p++) {
  62         char c = *p;
  63         if (c && strchr(doNotEscape, c))
  64             builder.append(c);
  65         else {
  66             char tmp[4];
  67             snprintf(tmp, sizeof(tmp), "%%%02X", static_cast<unsigned char>(c));
  68             builder.append(tmp);
  69         }
  70     }
  71     return builder.build(exec);
  72 }
  73
  74 static JSValue decode(ExecState* exec, const char* doNotUnescape, bool strict)
  75 {
  76     JSStringBuilder builder;
  77     UString str = exec->argument(0).toString(exec);
  78     int k = 0;
  79     int len = str.length();
  80     const UChar* d = str.characters();
  81     UChar u = 0;
  82     while (k < len) {
  83         const UChar* p = d + k;
  84         UChar c = *p;
  85         if (c == '%') {
  86             int charLen = 0;
  87             if (k <= len - 3 && isASCIIHexDigit(p[1]) && isASCIIHexDigit(p[2])) {
  88                 const char b0 = Lexer::convertHex(p[1], p[2]);
  89                 const int sequenceLen = UTF8SequenceLength(b0);
  90                 if (sequenceLen != 0 && k <= len - sequenceLen * 3) {
  91                     charLen = sequenceLen * 3;
  92                     char sequence[5];
  93                     sequence[0] = b0;
  94                     for (int i = 1; i < sequenceLen; ++i) {
  95                         const UChar* q = p + i * 3;
  96                         if (q[0] == '%' && isASCIIHexDigit(q[1]) && isASCIIHexDigit(q[2]))
  97                             sequence[i] = Lexer::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, "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 <= len - 6 && p[1] == 'u'
 123                         && isASCIIHexDigit(p[2]) && isASCIIHexDigit(p[3])
 124                         && isASCIIHexDigit(p[4]) && isASCIIHexDigit(p[5])) {
 125                     charLen = 6;
 126                     u = Lexer::convertUnicode(p[2], p[3], p[4], p[5]);
 127                 }
 128             }
 129             if (charLen && (u == 0 || u >= 128 || !strchr(doNotUnescape, u))) {
 130                 c = u;
 131                 k += charLen - 1;
 132             }
 133         }
 134         k++;
 135         builder.append(c);
 136     }
 137     return builder.build(exec);
 138 }
 139
 140 bool isStrWhiteSpace(UChar c)
 141 {
 142     switch (c) {
 143         // ECMA-262-5th 7.2 & 7.3
 144         case 0x0009:
 145         case 0x000A:
 146         case 0x000B:
 147         case 0x000C:
 148         case 0x000D:
 149         case 0x0020:
 150         case 0x00A0:
 151         case 0x2028:
 152         case 0x2029:
 153         case 0xFEFF:
 154             return true;
 155         default:
 156             return c > 0xff && isSeparatorSpace(c);
 157     }
 158 }
 159
 160 static int parseDigit(unsigned short c, int radix)
 161 {
 162     int digit = -1;
 163
 164     if (c >= '0' && c <= '9')
 165         digit = c - '0';
 166     else if (c >= 'A' && c <= 'Z')
 167         digit = c - 'A' + 10;
 168     else if (c >= 'a' && c <= 'z')
 169         digit = c - 'a' + 10;
 170
 171     if (digit >= radix)
 172         return -1;
 173     return digit;
 174 }
 175
 176 double parseIntOverflow(const char* s, int length, int radix)
 177 {
 178     double number = 0.0;
 179     double radixMultiplier = 1.0;
 180
 181     for (const char* p = s + length - 1; p >= s; p--) {
 182         if (radixMultiplier == Inf) {
 183             if (*p != '0') {
 184                 number = Inf;
 185                 break;
 186             }
 187         } else {
 188             int digit = parseDigit(*p, radix);
 189             number += digit * radixMultiplier;
 190         }
 191
 192         radixMultiplier *= radix;
 193     }
 194
 195     return number;
 196 }
 197
 198 double parseIntOverflow(const UChar* s, int length, int radix)
 199 {
 200     double number = 0.0;
 201     double radixMultiplier = 1.0;
 202
 203     for (const UChar* p = s + length - 1; p >= s; p--) {
 204         if (radixMultiplier == Inf) {
 205             if (*p != '0') {
 206                 number = Inf;
 207                 break;
 208             }
 209         } else {
 210             int digit = parseDigit(*p, radix);
 211             number += digit * radixMultiplier;
 212         }
 213
 214         radixMultiplier *= radix;
 215     }
 216
 217     return number;
 218 }
 219
 220 static double parseInt(const UString& s, int radix)
 221 {
 222     int length = s.length();
 223     const UChar* data = s.characters();
 224     int p = 0;
 225
 226     while (p < length && isStrWhiteSpace(data[p]))
 227         ++p;
 228
 229     double sign = 1;
 230     if (p < length) {
 231         if (data[p] == '+')
 232             ++p;
 233         else if (data[p] == '-') {
 234             sign = -1;
 235             ++p;
 236         }
 237     }
 238
 239     if ((radix == 0 || radix == 16) && length - p >= 2 && data[p] == '0' && (data[p + 1] == 'x' || data[p + 1] == 'X')) {
 240         radix = 16;
 241         p += 2;
 242     } else if (radix == 0) {
 243         if (p < length && data[p] == '0')
 244             radix = 8;
 245         else
 246             radix = 10;
 247     }
 248
 249     if (radix < 2 || radix > 36)
 250         return NaN;
 251
 252     int firstDigitPosition = p;
 253     bool sawDigit = false;
 254     double number = 0;
 255     while (p < length) {
 256         int digit = parseDigit(data[p], radix);
 257         if (digit == -1)
 258             break;
 259         sawDigit = true;
 260         number *= radix;
 261         number += digit;
 262         ++p;
 263     }
 264
 265     if (number >= mantissaOverflowLowerBound) {
 266         if (radix == 10)
 267             number = WTF::strtod(s.substringSharingImpl(firstDigitPosition, p - firstDigitPosition).utf8().data(), 0);
 268         else if (radix == 2 || radix == 4 || radix == 8 || radix == 16 || radix == 32)
 269             number = parseIntOverflow(s.substringSharingImpl(firstDigitPosition, p - firstDigitPosition).utf8().data(), p - firstDigitPosition, radix);
 270     }
 271
 272     if (!sawDigit)
 273         return NaN;
 274
 275     return sign * number;
 276 }
 277
 278 static const int SizeOfInfinity = 8;
 279
 280 static bool isInfinity(const UChar* data, const UChar* end)
 281 {
 282     return (end - data) >= SizeOfInfinity
 283         && data[0] == 'I'
 284         && data[1] == 'n'
 285         && data[2] == 'f'
 286         && data[3] == 'i'
 287         && data[4] == 'n'
 288         && data[5] == 'i'
 289         && data[6] == 't'
 290         && data[7] == 'y';
 291 }
 292
 293 // See ecma-262 9.3.1
 294 static double jsHexIntegerLiteral(const UChar*& data, const UChar* end)
 295 {
 296     // Hex number.
 297     data += 2;
 298     const UChar* firstDigitPosition = data;
 299     double number = 0;
 300     while (true) {
 301         number = number * 16 + toASCIIHexValue(*data);
 302         ++data;
 303         if (data == end)
 304             break;
 305         if (!isASCIIHexDigit(*data))
 306             break;
 307     }
 308     if (number >= mantissaOverflowLowerBound)
 309         number = parseIntOverflow(firstDigitPosition, data - firstDigitPosition, 16);
 310
 311     return number;
 312 }
 313
 314 // See ecma-262 9.3.1
 315 static double jsStrDecimalLiteral(const UChar*& data, const UChar* end)
 316 {
 317     ASSERT(data < end);
 318
 319     // Copy the sting into a null-terminated byte buffer, and call strtod.
 320     Vector<char, 32> byteBuffer;
 321     for (const UChar* characters = data; characters < end; ++characters) {
 322         UChar character = *characters;
 323         byteBuffer.append(isASCII(character) ? character : 0);
 324     }
 325     byteBuffer.append(0);
 326     char* endOfNumber;
 327     double number = WTF::strtod(byteBuffer.data(), &endOfNumber);
 328
 329     // Check if strtod found a number; if so return it.
 330     ptrdiff_t consumed = endOfNumber - byteBuffer.data();
 331     if (consumed) {
 332         data += consumed;
 333         return number;
 334     }
 335
 336     // Check for [+-]?Infinity
 337     switch (*data) {
 338     case 'I':
 339         if (isInfinity(data, end)) {
 340             data += SizeOfInfinity;
 341             return Inf;
 342         }
 343         break;
 344
 345     case '+':
 346         if (isInfinity(data + 1, end)) {
 347             data += SizeOfInfinity + 1;
 348             return Inf;
 349         }
 350         break;
 351
 352     case '-':
 353         if (isInfinity(data + 1, end)) {
 354             data += SizeOfInfinity + 1;
 355             return -Inf;
 356         }
 357         break;
 358     }
 359
 360     // Not a number.
 361     return NaN;
 362 }
 363
 364 // See ecma-262 9.3.1
 365 double jsToNumber(const UString& s)
 366 {
 367     unsigned size = s.length();
 368
 369     if (size == 1) {
 370         UChar c = s.characters()[0];
 371         if (isASCIIDigit(c))
 372             return c - '0';
 373         if (isStrWhiteSpace(c))
 374             return 0;
 375         return NaN;
 376     }
 377
 378     const UChar* data = s.characters();
 379     const UChar* end = data + size;
 380
 381     // Skip leading white space.
 382     for (; data < end; ++data) {
 383         if (!isStrWhiteSpace(*data))
 384             break;
 385     }
 386
 387     // Empty string.
 388     if (data == end)
 389         return 0.0;
 390
 391     double number;
 392     if (data[0] == '0' && data + 2 < end && (data[1] | 0x20) == 'x' && isASCIIHexDigit(data[2]))
 393         number = jsHexIntegerLiteral(data, end);
 394     else
 395         number = jsStrDecimalLiteral(data, end);
 396
 397     // Allow trailing white space.
 398     for (; data < end; ++data) {
 399         if (!isStrWhiteSpace(*data))
 400             break;
 401     }
 402     if (data != end)
 403         return NaN;
 404
 405     return number;
 406 }
 407
 408 static double parseFloat(const UString& s)
 409 {
 410     unsigned size = s.length();
 411
 412     if (size == 1) {
 413         UChar c = s.characters()[0];
 414         if (isASCIIDigit(c))
 415             return c - '0';
 416         return NaN;
 417     }
 418
 419     const UChar* data = s.characters();
 420     const UChar* end = data + size;
 421
 422     // Skip leading white space.
 423     for (; data < end; ++data) {
 424         if (!isStrWhiteSpace(*data))
 425             break;
 426     }
 427
 428     // Empty string.
 429     if (data == end)
 430         return NaN;
 431
 432     return jsStrDecimalLiteral(data, end);
 433 }
 434
 435 EncodedJSValue JSC_HOST_CALL globalFuncEval(ExecState* exec)
 436 {
 437     JSObject* thisObject = exec->hostThisValue().toThisObject(exec);
 438     JSObject* unwrappedObject = thisObject->unwrappedObject();
 439     if (!unwrappedObject->isGlobalObject() || static_cast<JSGlobalObject*>(unwrappedObject)->evalFunction() != exec->callee())
 440         return throwVMError(exec, createEvalError(exec, "The \"this\" value passed to eval must be the global object from which eval originated"));
 441
 442     JSValue x = exec->argument(0);
 443     if (!x.isString())
 444         return JSValue::encode(x);
 445
 446     UString s = x.toString(exec);
 447
 448     LiteralParser preparser(exec, s.characters(), s.length(), LiteralParser::NonStrictJSON);
 449     if (JSValue parsedObject = preparser.tryLiteralParse())
 450         return JSValue::encode(parsedObject);
 451
 452     EvalExecutable* eval = EvalExecutable::create(exec, makeSource(s), false);
 453     JSObject* error = eval->compile(exec, static_cast<JSGlobalObject*>(unwrappedObject)->globalScopeChain());
 454     if (error)
 455         return throwVMError(exec, error);
 456
 457     return JSValue::encode(exec->interpreter()->execute(eval, exec, thisObject, static_cast<JSGlobalObject*>(unwrappedObject)->globalScopeChain()));
 458 }
 459
 460 EncodedJSValue JSC_HOST_CALL globalFuncParseInt(ExecState* exec)
 461 {
 462     JSValue value = exec->argument(0);
 463     int32_t radix = exec->argument(1).toInt32(exec);
 464
 465     if (radix != 0 && radix != 10)
 466         return JSValue::encode(jsNumber(parseInt(value.toString(exec), radix)));
 467
 468     if (value.isInt32())
 469         return JSValue::encode(value);
 470
 471     if (value.isDouble()) {
 472         double d = value.asDouble();
 473         if (isfinite(d))
 474             return JSValue::encode(jsNumber((d > 0) ? floor(d) : ceil(d)));
 475         if (isnan(d) || isinf(d))
 476             return JSValue::encode(jsNaN());
 477         return JSValue::encode(jsNumber(0));
 478     }
 479
 480     return JSValue::encode(jsNumber(parseInt(value.toString(exec), radix)));
 481 }
 482
 483 EncodedJSValue JSC_HOST_CALL globalFuncParseFloat(ExecState* exec)
 484 {
 485     return JSValue::encode(jsNumber(parseFloat(exec->argument(0).toString(exec))));
 486 }
 487
 488 EncodedJSValue JSC_HOST_CALL globalFuncIsNaN(ExecState* exec)
 489 {
 490     return JSValue::encode(jsBoolean(isnan(exec->argument(0).toNumber(exec))));
 491 }
 492
 493 EncodedJSValue JSC_HOST_CALL globalFuncIsFinite(ExecState* exec)
 494 {
 495     double n = exec->argument(0).toNumber(exec);
 496     return JSValue::encode(jsBoolean(!isnan(n) && !isinf(n)));
 497 }
 498
 499 EncodedJSValue JSC_HOST_CALL globalFuncDecodeURI(ExecState* exec)
 500 {
 501     static const char do_not_unescape_when_decoding_URI[] =
 502         "#$&+,/:;=?@";
 503
 504     return JSValue::encode(decode(exec, do_not_unescape_when_decoding_URI, true));
 505 }
 506
 507 EncodedJSValue JSC_HOST_CALL globalFuncDecodeURIComponent(ExecState* exec)
 508 {
 509     return JSValue::encode(decode(exec, "", true));
 510 }
 511
 512 EncodedJSValue JSC_HOST_CALL globalFuncEncodeURI(ExecState* exec)
 513 {
 514     static const char do_not_escape_when_encoding_URI[] =
 515         "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
 516         "abcdefghijklmnopqrstuvwxyz"
 517         "0123456789"
 518         "!#$&'()*+,-./:;=?@_~";
 519
 520     return JSValue::encode(encode(exec, do_not_escape_when_encoding_URI));
 521 }
 522
 523 EncodedJSValue JSC_HOST_CALL globalFuncEncodeURIComponent(ExecState* exec)
 524 {
 525     static const char do_not_escape_when_encoding_URI_component[] =
 526         "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
 527         "abcdefghijklmnopqrstuvwxyz"
 528         "0123456789"
 529         "!'()*-._~";
 530
 531     return JSValue::encode(encode(exec, do_not_escape_when_encoding_URI_component));
 532 }
 533
 534 EncodedJSValue JSC_HOST_CALL globalFuncEscape(ExecState* exec)
 535 {
 536     static const char do_not_escape[] =
 537         "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
 538         "abcdefghijklmnopqrstuvwxyz"
 539         "0123456789"
 540         "*+-./@_";
 541
 542     JSStringBuilder builder;
 543     UString str = exec->argument(0).toString(exec);
 544     const UChar* c = str.characters();
 545     for (unsigned k = 0; k < str.length(); k++, c++) {
 546         int u = c[0];
 547         if (u > 255) {
 548             char tmp[7];
 549             snprintf(tmp, sizeof(tmp), "%%u%04X", u);
 550             builder.append(tmp);
 551         } else if (u != 0 && strchr(do_not_escape, static_cast<char>(u)))
 552             builder.append(c, 1);
 553         else {
 554             char tmp[4];
 555             snprintf(tmp, sizeof(tmp), "%%%02X", u);
 556             builder.append(tmp);
 557         }
 558     }
 559
 560     return JSValue::encode(builder.build(exec));
 561 }
 562
 563 EncodedJSValue JSC_HOST_CALL globalFuncUnescape(ExecState* exec)
 564 {
 565     UStringBuilder builder;
 566     UString str = exec->argument(0).toString(exec);
 567     int k = 0;
 568     int len = str.length();
 569     while (k < len) {
 570         const UChar* c = str.characters() + k;
 571         UChar u;
 572         if (c[0] == '%' && k <= len - 6 && c[1] == 'u') {
 573             if (isASCIIHexDigit(c[2]) && isASCIIHexDigit(c[3]) && isASCIIHexDigit(c[4]) && isASCIIHexDigit(c[5])) {
 574                 u = Lexer::convertUnicode(c[2], c[3], c[4], c[5]);
 575                 c = &u;
 576                 k += 5;
 577             }
 578         } else if (c[0] == '%' && k <= len - 3 && isASCIIHexDigit(c[1]) && isASCIIHexDigit(c[2])) {
 579             u = UChar(Lexer::convertHex(c[1], c[2]));
 580             c = &u;
 581             k += 2;
 582         }
 583         k++;
 584         builder.append(*c);
 585     }
 586
 587     return JSValue::encode(jsString(exec, builder.toUString()));
 588 }
 589
 590 } // namespace JSC