Annotation of parser3/src/lib/punycode/pa_convert_utf.c, revision 1.1
1.1 ! moko 1: /*===--- pa_convert_utf.c - Universal Character Names conversions ---------------===
! 2: *
! 3: * The LLVM Compiler Infrastructure
! 4: *
! 5: * This file is distributed under the University of Illinois Open Source
! 6: * License. See LICENSE.TXT for details.
! 7: *
! 8: *===------------------------------------------------------------------------=*/
! 9: /*
! 10: * Copyright 2001-2004 Unicode, Inc.
! 11: *
! 12: * Disclaimer
! 13: *
! 14: * This source code is provided as is by Unicode, Inc. No claims are
! 15: * made as to fitness for any particular purpose. No warranties of any
! 16: * kind are expressed or implied. The recipient agrees to determine
! 17: * applicability of information provided. If this file has been
! 18: * purchased on magnetic or optical media from Unicode, Inc., the
! 19: * sole remedy for any claim will be exchange of defective media
! 20: * within 90 days of receipt.
! 21: *
! 22: * Limitations on Rights to Redistribute This Code
! 23: *
! 24: * Unicode, Inc. hereby grants the right to freely use the information
! 25: * supplied in this file in the creation of products supporting the
! 26: * Unicode Standard, and to make copies of this file in any form
! 27: * for internal or external distribution as long as this notice
! 28: * remains attached.
! 29: */
! 30:
! 31: /* ---------------------------------------------------------------------
! 32:
! 33: Conversions between UTF32, UTF-16, and UTF-8. Source code file.
! 34: Author: Mark E. Davis, 1994.
! 35: Rev History: Rick McGowan, fixes & updates May 2001.
! 36: Sept 2001: fixed const & error conditions per
! 37: mods suggested by S. Parent & A. Lillich.
! 38: June 2002: Tim Dodd added detection and handling of incomplete
! 39: source sequences, enhanced error detection, added casts
! 40: to eliminate compiler warnings.
! 41: July 2003: slight mods to back out aggressive FFFE detection.
! 42: Jan 2004: updated switches in from-UTF8 conversions.
! 43: Oct 2004: updated to use UNI_MAX_LEGAL_UTF32 in UTF-32 conversions.
! 44:
! 45: See the header file "ConvertUTF.h" for complete documentation.
! 46:
! 47: ------------------------------------------------------------------------ */
! 48:
! 49:
! 50: #include "pa_convert_utf.h"
! 51:
! 52: static const int halfShift = 10; /* used for shifting by 10 bits */
! 53:
! 54: static const UTF32 halfBase = 0x0010000UL;
! 55: static const UTF32 halfMask = 0x3FFUL;
! 56:
! 57: #define UNI_SUR_HIGH_START (UTF32)0xD800
! 58: #define UNI_SUR_HIGH_END (UTF32)0xDBFF
! 59: #define UNI_SUR_LOW_START (UTF32)0xDC00
! 60: #define UNI_SUR_LOW_END (UTF32)0xDFFF
! 61: #define false 0
! 62: #define true 1
! 63:
! 64: /* --------------------------------------------------------------------- */
! 65:
! 66: /*
! 67: * Index into the table below with the first byte of a UTF-8 sequence to
! 68: * get the number of trailing bytes that are supposed to follow it.
! 69: * Note that *legal* UTF-8 values can't have 4 or 5-bytes. The table is
! 70: * left as-is for anyone who may want to do such conversion, which was
! 71: * allowed in earlier algorithms.
! 72: */
! 73: static const char trailingBytesForUTF8[256] = {
! 74: 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
! 75: 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
! 76: 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
! 77: 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
! 78: 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
! 79: 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
! 80: 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
! 81: 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2, 3,3,3,3,3,3,3,3,4,4,4,4,5,5,5,5
! 82: };
! 83:
! 84: /*
! 85: * Magic values subtracted from a buffer value during UTF8 conversion.
! 86: * This table contains as many values as there might be trailing bytes
! 87: * in a UTF-8 sequence.
! 88: */
! 89: static const UTF32 offsetsFromUTF8[6] = { 0x00000000UL, 0x00003080UL, 0x000E2080UL,
! 90: 0x03C82080UL, 0xFA082080UL, 0x82082080UL };
! 91:
! 92: /*
! 93: * Once the bits are split out into bytes of UTF-8, this is a mask OR-ed
! 94: * into the first byte, depending on how many bytes follow. There are
! 95: * as many entries in this table as there are UTF-8 sequence types.
! 96: * (I.e., one byte sequence, two byte... etc.). Remember that sequencs
! 97: * for *legal* UTF-8 will be 4 or fewer bytes total.
! 98: */
! 99: static const UTF8 firstByteMark[7] = { 0x00, 0x00, 0xC0, 0xE0, 0xF0, 0xF8, 0xFC };
! 100:
! 101: /* --------------------------------------------------------------------- */
! 102:
! 103: /* The interface converts a whole buffer to avoid function-call overhead.
! 104: * Constants have been gathered. Loops & conditionals have been removed as
! 105: * much as possible for efficiency, in favor of drop-through switches.
! 106: * (See "Note A" at the bottom of the file for equivalent code.)
! 107: * If your compiler supports it, the "isLegalUTF8" call can be turned
! 108: * into an inline function.
! 109: */
! 110:
! 111:
! 112: /* --------------------------------------------------------------------- */
! 113:
! 114: ConversionResult pa_convertUTF32toUTF16 (
! 115: const UTF32** sourceStart, const UTF32* sourceEnd,
! 116: UTF16** targetStart, UTF16* targetEnd, ConversionFlags flags) {
! 117: ConversionResult result = conversionOK;
! 118: const UTF32* source = *sourceStart;
! 119: UTF16* target = *targetStart;
! 120: while (source < sourceEnd) {
! 121: UTF32 ch;
! 122: if (target >= targetEnd) {
! 123: result = targetExhausted; break;
! 124: }
! 125: ch = *source++;
! 126: if (ch <= UNI_MAX_BMP) { /* Target is a character <= 0xFFFF */
! 127: /* UTF-16 surrogate values are illegal in UTF-32; 0xffff or 0xfffe are both reserved values */
! 128: if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_LOW_END) {
! 129: if (flags == strictConversion) {
! 130: --source; /* return to the illegal value itself */
! 131: result = sourceIllegal;
! 132: break;
! 133: } else {
! 134: *target++ = UNI_REPLACEMENT_CHAR;
! 135: }
! 136: } else {
! 137: *target++ = (UTF16)ch; /* normal case */
! 138: }
! 139: } else if (ch > UNI_MAX_LEGAL_UTF32) {
! 140: if (flags == strictConversion) {
! 141: result = sourceIllegal;
! 142: } else {
! 143: *target++ = UNI_REPLACEMENT_CHAR;
! 144: }
! 145: } else {
! 146: /* target is a character in range 0xFFFF - 0x10FFFF. */
! 147: if (target + 1 >= targetEnd) {
! 148: --source; /* Back up source pointer! */
! 149: result = targetExhausted; break;
! 150: }
! 151: ch -= halfBase;
! 152: *target++ = (UTF16)((ch >> halfShift) + UNI_SUR_HIGH_START);
! 153: *target++ = (UTF16)((ch & halfMask) + UNI_SUR_LOW_START);
! 154: }
! 155: }
! 156: *sourceStart = source;
! 157: *targetStart = target;
! 158: return result;
! 159: }
! 160:
! 161: /* --------------------------------------------------------------------- */
! 162:
! 163: ConversionResult pa_convertUTF16toUTF32 (
! 164: const UTF16** sourceStart, const UTF16* sourceEnd,
! 165: UTF32** targetStart, UTF32* targetEnd, ConversionFlags flags) {
! 166: ConversionResult result = conversionOK;
! 167: const UTF16* source = *sourceStart;
! 168: UTF32* target = *targetStart;
! 169: UTF32 ch, ch2;
! 170: while (source < sourceEnd) {
! 171: const UTF16* oldSource = source; /* In case we have to back up because of target overflow. */
! 172: ch = *source++;
! 173: /* If we have a surrogate pair, convert to UTF32 first. */
! 174: if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_HIGH_END) {
! 175: /* If the 16 bits following the high surrogate are in the source buffer... */
! 176: if (source < sourceEnd) {
! 177: ch2 = *source;
! 178: /* If it's a low surrogate, convert to UTF32. */
! 179: if (ch2 >= UNI_SUR_LOW_START && ch2 <= UNI_SUR_LOW_END) {
! 180: ch = ((ch - UNI_SUR_HIGH_START) << halfShift)
! 181: + (ch2 - UNI_SUR_LOW_START) + halfBase;
! 182: ++source;
! 183: } else if (flags == strictConversion) { /* it's an unpaired high surrogate */
! 184: --source; /* return to the illegal value itself */
! 185: result = sourceIllegal;
! 186: break;
! 187: }
! 188: } else { /* We don't have the 16 bits following the high surrogate. */
! 189: --source; /* return to the high surrogate */
! 190: result = sourceExhausted;
! 191: break;
! 192: }
! 193: } else if (flags == strictConversion) {
! 194: /* UTF-16 surrogate values are illegal in UTF-32 */
! 195: if (ch >= UNI_SUR_LOW_START && ch <= UNI_SUR_LOW_END) {
! 196: --source; /* return to the illegal value itself */
! 197: result = sourceIllegal;
! 198: break;
! 199: }
! 200: }
! 201: if (target >= targetEnd) {
! 202: source = oldSource; /* Back up source pointer! */
! 203: result = targetExhausted; break;
! 204: }
! 205: *target++ = ch;
! 206: }
! 207: *sourceStart = source;
! 208: *targetStart = target;
! 209: return result;
! 210: }
! 211:
! 212: ConversionResult pa_convertUTF16toUTF8 (
! 213: const UTF16** sourceStart, const UTF16* sourceEnd,
! 214: UTF8** targetStart, UTF8* targetEnd, ConversionFlags flags) {
! 215: ConversionResult result = conversionOK;
! 216: const UTF16* source = *sourceStart;
! 217: UTF8* target = *targetStart;
! 218: while (source < sourceEnd) {
! 219: UTF32 ch;
! 220: unsigned short bytesToWrite = 0;
! 221: const UTF32 byteMask = 0xBF;
! 222: const UTF32 byteMark = 0x80;
! 223: const UTF16* oldSource = source; /* In case we have to back up because of target overflow. */
! 224: ch = *source++;
! 225: /* If we have a surrogate pair, convert to UTF32 first. */
! 226: if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_HIGH_END) {
! 227: /* If the 16 bits following the high surrogate are in the source buffer... */
! 228: if (source < sourceEnd) {
! 229: UTF32 ch2 = *source;
! 230: /* If it's a low surrogate, convert to UTF32. */
! 231: if (ch2 >= UNI_SUR_LOW_START && ch2 <= UNI_SUR_LOW_END) {
! 232: ch = ((ch - UNI_SUR_HIGH_START) << halfShift)
! 233: + (ch2 - UNI_SUR_LOW_START) + halfBase;
! 234: ++source;
! 235: } else if (flags == strictConversion) { /* it's an unpaired high surrogate */
! 236: --source; /* return to the illegal value itself */
! 237: result = sourceIllegal;
! 238: break;
! 239: }
! 240: } else { /* We don't have the 16 bits following the high surrogate. */
! 241: --source; /* return to the high surrogate */
! 242: result = sourceExhausted;
! 243: break;
! 244: }
! 245: } else if (flags == strictConversion) {
! 246: /* UTF-16 surrogate values are illegal in UTF-32 */
! 247: if (ch >= UNI_SUR_LOW_START && ch <= UNI_SUR_LOW_END) {
! 248: --source; /* return to the illegal value itself */
! 249: result = sourceIllegal;
! 250: break;
! 251: }
! 252: }
! 253: /* Figure out how many bytes the result will require */
! 254: if (ch < (UTF32)0x80) { bytesToWrite = 1;
! 255: } else if (ch < (UTF32)0x800) { bytesToWrite = 2;
! 256: } else if (ch < (UTF32)0x10000) { bytesToWrite = 3;
! 257: } else if (ch < (UTF32)0x110000) { bytesToWrite = 4;
! 258: } else { bytesToWrite = 3;
! 259: ch = UNI_REPLACEMENT_CHAR;
! 260: }
! 261:
! 262: target += bytesToWrite;
! 263: if (target > targetEnd) {
! 264: source = oldSource; /* Back up source pointer! */
! 265: target -= bytesToWrite; result = targetExhausted; break;
! 266: }
! 267: switch (bytesToWrite) { /* note: everything falls through. */
! 268: case 4: *--target = (UTF8)((ch | byteMark) & byteMask); ch >>= 6;
! 269: case 3: *--target = (UTF8)((ch | byteMark) & byteMask); ch >>= 6;
! 270: case 2: *--target = (UTF8)((ch | byteMark) & byteMask); ch >>= 6;
! 271: case 1: *--target = (UTF8)(ch | firstByteMark[bytesToWrite]);
! 272: }
! 273: target += bytesToWrite;
! 274: }
! 275: *sourceStart = source;
! 276: *targetStart = target;
! 277: return result;
! 278: }
! 279:
! 280: /* --------------------------------------------------------------------- */
! 281:
! 282: ConversionResult pa_convertUTF32toUTF8 (
! 283: const UTF32** sourceStart, const UTF32* sourceEnd,
! 284: UTF8** targetStart, UTF8* targetEnd, ConversionFlags flags) {
! 285: ConversionResult result = conversionOK;
! 286: const UTF32* source = *sourceStart;
! 287: UTF8* target = *targetStart;
! 288: while (source < sourceEnd) {
! 289: UTF32 ch;
! 290: unsigned short bytesToWrite = 0;
! 291: const UTF32 byteMask = 0xBF;
! 292: const UTF32 byteMark = 0x80;
! 293: ch = *source++;
! 294: if (flags == strictConversion ) {
! 295: /* UTF-16 surrogate values are illegal in UTF-32 */
! 296: if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_LOW_END) {
! 297: --source; /* return to the illegal value itself */
! 298: result = sourceIllegal;
! 299: break;
! 300: }
! 301: }
! 302: /*
! 303: * Figure out how many bytes the result will require. Turn any
! 304: * illegally large UTF32 things (> Plane 17) into replacement chars.
! 305: */
! 306: if (ch < (UTF32)0x80) { bytesToWrite = 1;
! 307: } else if (ch < (UTF32)0x800) { bytesToWrite = 2;
! 308: } else if (ch < (UTF32)0x10000) { bytesToWrite = 3;
! 309: } else if (ch <= UNI_MAX_LEGAL_UTF32) { bytesToWrite = 4;
! 310: } else { bytesToWrite = 3;
! 311: ch = UNI_REPLACEMENT_CHAR;
! 312: result = sourceIllegal;
! 313: }
! 314:
! 315: target += bytesToWrite;
! 316: if (target > targetEnd) {
! 317: --source; /* Back up source pointer! */
! 318: target -= bytesToWrite; result = targetExhausted; break;
! 319: }
! 320: switch (bytesToWrite) { /* note: everything falls through. */
! 321: case 4: *--target = (UTF8)((ch | byteMark) & byteMask); ch >>= 6;
! 322: case 3: *--target = (UTF8)((ch | byteMark) & byteMask); ch >>= 6;
! 323: case 2: *--target = (UTF8)((ch | byteMark) & byteMask); ch >>= 6;
! 324: case 1: *--target = (UTF8) (ch | firstByteMark[bytesToWrite]);
! 325: }
! 326: target += bytesToWrite;
! 327: }
! 328: *sourceStart = source;
! 329: *targetStart = target;
! 330: return result;
! 331: }
! 332:
! 333: /* --------------------------------------------------------------------- */
! 334:
! 335: /*
! 336: * Utility routine to tell whether a sequence of bytes is legal UTF-8.
! 337: * This must be called with the length pre-determined by the first byte.
! 338: * If not calling this from ConvertUTF8to*, then the length can be set by:
! 339: * length = trailingBytesForUTF8[*source]+1;
! 340: * and the sequence is illegal right away if there aren't that many bytes
! 341: * available.
! 342: * If presented with a length > 4, this returns false. The Unicode
! 343: * definition of UTF-8 goes up to 4-byte sequences.
! 344: */
! 345:
! 346: static Boolean isLegalUTF8(const UTF8 *source, int length) {
! 347: UTF8 a;
! 348: const UTF8 *srcptr = source+length;
! 349: switch (length) {
! 350: default: return false;
! 351: /* Everything else falls through when "true"... */
! 352: case 4: if ((a = (*--srcptr)) < 0x80 || a > 0xBF) return false;
! 353: case 3: if ((a = (*--srcptr)) < 0x80 || a > 0xBF) return false;
! 354: case 2: if ((a = (*--srcptr)) < 0x80 || a > 0xBF) return false;
! 355:
! 356: switch (*source) {
! 357: /* no fall-through in this inner switch */
! 358: case 0xE0: if (a < 0xA0) return false; break;
! 359: case 0xED: if (a > 0x9F) return false; break;
! 360: case 0xF0: if (a < 0x90) return false; break;
! 361: case 0xF4: if (a > 0x8F) return false; break;
! 362: default: if (a < 0x80) return false;
! 363: }
! 364:
! 365: case 1: if (*source >= 0x80 && *source < 0xC2) return false;
! 366: }
! 367: if (*source > 0xF4) return false;
! 368: return true;
! 369: }
! 370:
! 371: /* --------------------------------------------------------------------- */
! 372:
! 373: /*
! 374: * Exported function to return whether a UTF-8 sequence is legal or not.
! 375: * This is not used here; it's just exported.
! 376: */
! 377: Boolean pa_isLegalUTF8Sequence(const UTF8 *source, const UTF8 *sourceEnd) {
! 378: int length = trailingBytesForUTF8[*source]+1;
! 379: if (length > sourceEnd - source) {
! 380: return false;
! 381: }
! 382: return isLegalUTF8(source, length);
! 383: }
! 384:
! 385: /* --------------------------------------------------------------------- */
! 386:
! 387: static unsigned
! 388: findMaximalSubpartOfIllFormedUTF8Sequence(const UTF8 *source,
! 389: const UTF8 *sourceEnd) {
! 390: UTF8 b1, b2, b3;
! 391:
! 392: assert(!isLegalUTF8Sequence(source, sourceEnd));
! 393:
! 394: /*
! 395: * Unicode 6.3.0, D93b:
! 396: *
! 397: * Maximal subpart of an ill-formed subsequence: The longest code unit
! 398: * subsequence starting at an unconvertible offset that is either:
! 399: * a. the initial subsequence of a well-formed code unit sequence, or
! 400: * b. a subsequence of length one.
! 401: */
! 402:
! 403: if (source == sourceEnd)
! 404: return 0;
! 405:
! 406: /*
! 407: * Perform case analysis. See Unicode 6.3.0, Table 3-7. Well-Formed UTF-8
! 408: * Byte Sequences.
! 409: */
! 410:
! 411: b1 = *source;
! 412: ++source;
! 413: if (b1 >= 0xC2 && b1 <= 0xDF) {
! 414: /*
! 415: * First byte is valid, but we know that this code unit sequence is
! 416: * invalid, so the maximal subpart has to end after the first byte.
! 417: */
! 418: return 1;
! 419: }
! 420:
! 421: if (source == sourceEnd)
! 422: return 1;
! 423:
! 424: b2 = *source;
! 425: ++source;
! 426:
! 427: if (b1 == 0xE0) {
! 428: return (b2 >= 0xA0 && b2 <= 0xBF) ? 2 : 1;
! 429: }
! 430: if (b1 >= 0xE1 && b1 <= 0xEC) {
! 431: return (b2 >= 0x80 && b2 <= 0xBF) ? 2 : 1;
! 432: }
! 433: if (b1 == 0xED) {
! 434: return (b2 >= 0x80 && b2 <= 0x9F) ? 2 : 1;
! 435: }
! 436: if (b1 >= 0xEE && b1 <= 0xEF) {
! 437: return (b2 >= 0x80 && b2 <= 0xBF) ? 2 : 1;
! 438: }
! 439: if (b1 == 0xF0) {
! 440: if (b2 >= 0x90 && b2 <= 0xBF) {
! 441: if (source == sourceEnd)
! 442: return 2;
! 443:
! 444: b3 = *source;
! 445: return (b3 >= 0x80 && b3 <= 0xBF) ? 3 : 2;
! 446: }
! 447: return 1;
! 448: }
! 449: if (b1 >= 0xF1 && b1 <= 0xF3) {
! 450: if (b2 >= 0x80 && b2 <= 0xBF) {
! 451: if (source == sourceEnd)
! 452: return 2;
! 453:
! 454: b3 = *source;
! 455: return (b3 >= 0x80 && b3 <= 0xBF) ? 3 : 2;
! 456: }
! 457: return 1;
! 458: }
! 459: if (b1 == 0xF4) {
! 460: if (b2 >= 0x80 && b2 <= 0x8F) {
! 461: if (source == sourceEnd)
! 462: return 2;
! 463:
! 464: b3 = *source;
! 465: return (b3 >= 0x80 && b3 <= 0xBF) ? 3 : 2;
! 466: }
! 467: return 1;
! 468: }
! 469:
! 470: assert((b1 >= 0x80 && b1 <= 0xC1) || b1 >= 0xF5);
! 471: /*
! 472: * There are no valid sequences that start with these bytes. Maximal subpart
! 473: * is defined to have length 1 in these cases.
! 474: */
! 475: return 1;
! 476: }
! 477:
! 478: /* --------------------------------------------------------------------- */
! 479:
! 480: /*
! 481: * Exported function to return the total number of bytes in a codepoint
! 482: * represented in UTF-8, given the value of the first byte.
! 483: */
! 484: unsigned pa_getNumBytesForUTF8(UTF8 first) {
! 485: return trailingBytesForUTF8[first] + 1;
! 486: }
! 487:
! 488: /* --------------------------------------------------------------------- */
! 489:
! 490: /*
! 491: * Exported function to return whether a UTF-8 string is legal or not.
! 492: * This is not used here; it's just exported.
! 493: */
! 494: Boolean pa_isLegalUTF8String(const UTF8 **source, const UTF8 *sourceEnd) {
! 495: while (*source != sourceEnd) {
! 496: int length = trailingBytesForUTF8[**source] + 1;
! 497: if (length > sourceEnd - *source || !isLegalUTF8(*source, length))
! 498: return false;
! 499: *source += length;
! 500: }
! 501: return true;
! 502: }
! 503:
! 504: /* --------------------------------------------------------------------- */
! 505:
! 506: ConversionResult pa_convertUTF8toUTF16 (
! 507: const UTF8** sourceStart, const UTF8* sourceEnd,
! 508: UTF16** targetStart, UTF16* targetEnd, ConversionFlags flags) {
! 509: ConversionResult result = conversionOK;
! 510: const UTF8* source = *sourceStart;
! 511: UTF16* target = *targetStart;
! 512: while (source < sourceEnd) {
! 513: UTF32 ch = 0;
! 514: unsigned short extraBytesToRead = trailingBytesForUTF8[*source];
! 515: if (extraBytesToRead >= sourceEnd - source) {
! 516: result = sourceExhausted; break;
! 517: }
! 518: /* Do this check whether lenient or strict */
! 519: if (!isLegalUTF8(source, extraBytesToRead+1)) {
! 520: result = sourceIllegal;
! 521: break;
! 522: }
! 523: /*
! 524: * The cases all fall through. See "Note A" below.
! 525: */
! 526: switch (extraBytesToRead) {
! 527: case 5: ch += *source++; ch <<= 6; /* remember, illegal UTF-8 */
! 528: case 4: ch += *source++; ch <<= 6; /* remember, illegal UTF-8 */
! 529: case 3: ch += *source++; ch <<= 6;
! 530: case 2: ch += *source++; ch <<= 6;
! 531: case 1: ch += *source++; ch <<= 6;
! 532: case 0: ch += *source++;
! 533: }
! 534: ch -= offsetsFromUTF8[extraBytesToRead];
! 535:
! 536: if (target >= targetEnd) {
! 537: source -= (extraBytesToRead+1); /* Back up source pointer! */
! 538: result = targetExhausted; break;
! 539: }
! 540: if (ch <= UNI_MAX_BMP) { /* Target is a character <= 0xFFFF */
! 541: /* UTF-16 surrogate values are illegal in UTF-32 */
! 542: if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_LOW_END) {
! 543: if (flags == strictConversion) {
! 544: source -= (extraBytesToRead+1); /* return to the illegal value itself */
! 545: result = sourceIllegal;
! 546: break;
! 547: } else {
! 548: *target++ = UNI_REPLACEMENT_CHAR;
! 549: }
! 550: } else {
! 551: *target++ = (UTF16)ch; /* normal case */
! 552: }
! 553: } else if (ch > UNI_MAX_UTF16) {
! 554: if (flags == strictConversion) {
! 555: result = sourceIllegal;
! 556: source -= (extraBytesToRead+1); /* return to the start */
! 557: break; /* Bail out; shouldn't continue */
! 558: } else {
! 559: *target++ = UNI_REPLACEMENT_CHAR;
! 560: }
! 561: } else {
! 562: /* target is a character in range 0xFFFF - 0x10FFFF. */
! 563: if (target + 1 >= targetEnd) {
! 564: source -= (extraBytesToRead+1); /* Back up source pointer! */
! 565: result = targetExhausted; break;
! 566: }
! 567: ch -= halfBase;
! 568: *target++ = (UTF16)((ch >> halfShift) + UNI_SUR_HIGH_START);
! 569: *target++ = (UTF16)((ch & halfMask) + UNI_SUR_LOW_START);
! 570: }
! 571: }
! 572: *sourceStart = source;
! 573: *targetStart = target;
! 574: return result;
! 575: }
! 576:
! 577: /* --------------------------------------------------------------------- */
! 578:
! 579: static ConversionResult ConvertUTF8toUTF32Impl(
! 580: const UTF8** sourceStart, const UTF8* sourceEnd,
! 581: UTF32** targetStart, UTF32* targetEnd, ConversionFlags flags,
! 582: Boolean InputIsPartial) {
! 583: ConversionResult result = conversionOK;
! 584: const UTF8* source = *sourceStart;
! 585: UTF32* target = *targetStart;
! 586: while (source < sourceEnd) {
! 587: UTF32 ch = 0;
! 588: unsigned short extraBytesToRead = trailingBytesForUTF8[*source];
! 589: if (extraBytesToRead >= sourceEnd - source) {
! 590: if (flags == strictConversion || InputIsPartial) {
! 591: result = sourceExhausted;
! 592: break;
! 593: } else {
! 594: result = sourceIllegal;
! 595:
! 596: /*
! 597: * Replace the maximal subpart of ill-formed sequence with
! 598: * replacement character.
! 599: */
! 600: source += findMaximalSubpartOfIllFormedUTF8Sequence(source,
! 601: sourceEnd);
! 602: *target++ = UNI_REPLACEMENT_CHAR;
! 603: continue;
! 604: }
! 605: }
! 606: if (target >= targetEnd) {
! 607: result = targetExhausted; break;
! 608: }
! 609:
! 610: /* Do this check whether lenient or strict */
! 611: if (!isLegalUTF8(source, extraBytesToRead+1)) {
! 612: result = sourceIllegal;
! 613: if (flags == strictConversion) {
! 614: /* Abort conversion. */
! 615: break;
! 616: } else {
! 617: /*
! 618: * Replace the maximal subpart of ill-formed sequence with
! 619: * replacement character.
! 620: */
! 621: source += findMaximalSubpartOfIllFormedUTF8Sequence(source,
! 622: sourceEnd);
! 623: *target++ = UNI_REPLACEMENT_CHAR;
! 624: continue;
! 625: }
! 626: }
! 627: /*
! 628: * The cases all fall through. See "Note A" below.
! 629: */
! 630: switch (extraBytesToRead) {
! 631: case 5: ch += *source++; ch <<= 6;
! 632: case 4: ch += *source++; ch <<= 6;
! 633: case 3: ch += *source++; ch <<= 6;
! 634: case 2: ch += *source++; ch <<= 6;
! 635: case 1: ch += *source++; ch <<= 6;
! 636: case 0: ch += *source++;
! 637: }
! 638: ch -= offsetsFromUTF8[extraBytesToRead];
! 639:
! 640: if (ch <= UNI_MAX_LEGAL_UTF32) {
! 641: /*
! 642: * UTF-16 surrogate values are illegal in UTF-32, and anything
! 643: * over Plane 17 (> 0x10FFFF) is illegal.
! 644: */
! 645: if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_LOW_END) {
! 646: if (flags == strictConversion) {
! 647: source -= (extraBytesToRead+1); /* return to the illegal value itself */
! 648: result = sourceIllegal;
! 649: break;
! 650: } else {
! 651: *target++ = UNI_REPLACEMENT_CHAR;
! 652: }
! 653: } else {
! 654: *target++ = ch;
! 655: }
! 656: } else { /* i.e., ch > UNI_MAX_LEGAL_UTF32 */
! 657: result = sourceIllegal;
! 658: *target++ = UNI_REPLACEMENT_CHAR;
! 659: }
! 660: }
! 661: *sourceStart = source;
! 662: *targetStart = target;
! 663: return result;
! 664: }
! 665:
! 666: ConversionResult pa_convertUTF8toUTF32Partial(const UTF8 **sourceStart,
! 667: const UTF8 *sourceEnd,
! 668: UTF32 **targetStart,
! 669: UTF32 *targetEnd,
! 670: ConversionFlags flags) {
! 671: return ConvertUTF8toUTF32Impl(sourceStart, sourceEnd, targetStart, targetEnd,
! 672: flags, /*InputIsPartial=*/true);
! 673: }
! 674:
! 675: ConversionResult pa_convertUTF8toUTF32(const UTF8 **sourceStart,
! 676: const UTF8 *sourceEnd, UTF32 **targetStart,
! 677: UTF32 *targetEnd, ConversionFlags flags) {
! 678: return ConvertUTF8toUTF32Impl(sourceStart, sourceEnd, targetStart, targetEnd,
! 679: flags, /*InputIsPartial=*/false);
! 680: }
! 681:
! 682: /* ---------------------------------------------------------------------
! 683:
! 684: Note A.
! 685: The fall-through switches in UTF-8 reading code save a
! 686: temp variable, some decrements & conditionals. The switches
! 687: are equivalent to the following loop:
! 688: {
! 689: int tmpBytesToRead = extraBytesToRead+1;
! 690: do {
! 691: ch += *source++;
! 692: --tmpBytesToRead;
! 693: if (tmpBytesToRead) ch <<= 6;
! 694: } while (tmpBytesToRead > 0);
! 695: }
! 696: In UTF-8 writing code, the switches on "bytesToWrite" are
! 697: similarly unrolled loops.
! 698:
! 699: --------------------------------------------------------------------- */
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