DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Implementation

Mercurial (5216dd412535)

VCS Links

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935
/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 * ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is Mozilla Foundation code.
 *
 * The Initial Developer of the Original Code is Mozilla Foundation.
 * Portions created by the Initial Developer are Copyright (C) 2005-2009
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Stuart Parmenter <stuart@mozilla.com>
 *   John Daggett <jdaggett@mozilla.com>
 *   Jonathan Kew <jfkthame@gmail.com>
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either the GNU General Public License Version 2 or later (the "GPL"), or
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

#ifndef GFX_FONT_UTILS_H
#define GFX_FONT_UTILS_H

#include "gfxTypes.h"

#include "prtypes.h"
#include "prcpucfg.h"

#include "nsDataHashtable.h"

#include "nsITimer.h"
#include "nsCOMPtr.h"
#include "nsIRunnable.h"
#include "nsThreadUtils.h"
#include "nsComponentManagerUtils.h"
#include "nsTArray.h"
#include "nsAutoPtr.h"
#include "nsIStreamBufferAccess.h"

/* Bug 341128 - w32api defines min/max which causes problems with <bitset> */
#ifdef __MINGW32__
#undef min
#undef max
#endif

class gfxSparseBitSet {
private:
    enum { BLOCK_SIZE = 32 };   // ==> 256 codepoints per block
    enum { BLOCK_SIZE_BITS = BLOCK_SIZE * 8 };
    enum { BLOCK_INDEX_SHIFT = 8 };

    struct Block {
        Block(const Block& aBlock) { memcpy(mBits, aBlock.mBits, sizeof(mBits)); }
        Block(unsigned char memsetValue = 0) { memset(mBits, memsetValue, BLOCK_SIZE); }
        PRUint8 mBits[BLOCK_SIZE];
    };

public:
    gfxSparseBitSet() { }
    gfxSparseBitSet(const gfxSparseBitSet& aBitset) {
        PRUint32 len = aBitset.mBlocks.Length();
        mBlocks.AppendElements(len);
        for (PRUint32 i = 0; i < len; ++i) {
            Block *block = aBitset.mBlocks[i];
            if (block)
                mBlocks[i] = new Block(*block);
        }
    }
    PRBool test(PRUint32 aIndex) const {
        NS_ASSERTION(mBlocks.DebugGetHeader(), "mHdr is null, this is bad");
        PRUint32 blockIndex = aIndex/BLOCK_SIZE_BITS;
        if (blockIndex >= mBlocks.Length())
            return PR_FALSE;
        Block *block = mBlocks[blockIndex];
        if (!block)
            return PR_FALSE;
        return ((block->mBits[(aIndex>>3) & (BLOCK_SIZE - 1)]) & (1 << (aIndex & 0x7))) != 0;
    }

    PRBool TestRange(PRUint32 aStart, PRUint32 aEnd) {
        PRUint32 startBlock, endBlock, blockLen;
        
        // start point is beyond the end of the block array? return false immediately
        startBlock = aStart >> BLOCK_INDEX_SHIFT;
        blockLen = mBlocks.Length();
        if (startBlock >= blockLen) return PR_FALSE;
        
        // check for blocks in range, if none, return false
        PRUint32 blockIndex;
        PRBool hasBlocksInRange = PR_FALSE;

        endBlock = aEnd >> BLOCK_INDEX_SHIFT;
        blockIndex = startBlock;
        for (blockIndex = startBlock; blockIndex <= endBlock; blockIndex++) {
            if (blockIndex < blockLen && mBlocks[blockIndex])
                hasBlocksInRange = PR_TRUE;
        }
        if (!hasBlocksInRange) return PR_FALSE;

        Block *block;
        PRUint32 i, start, end;
        
        // first block, check bits
        if ((block = mBlocks[startBlock])) {
            start = aStart;
            end = PR_MIN(aEnd, ((startBlock+1) << BLOCK_INDEX_SHIFT) - 1);
            for (i = start; i <= end; i++) {
                if ((block->mBits[(i>>3) & (BLOCK_SIZE - 1)]) & (1 << (i & 0x7)))
                    return PR_TRUE;
            }
        }
        if (endBlock == startBlock) return PR_FALSE;

        // [2..n-1] blocks check bytes
        for (blockIndex = startBlock + 1; blockIndex < endBlock; blockIndex++) {
            PRUint32 index;
            
            if (blockIndex >= blockLen || !(block = mBlocks[blockIndex])) continue;
            for (index = 0; index < BLOCK_SIZE; index++) {
                if (block->mBits[index]) 
                    return PR_TRUE;
            }
        }
        
        // last block, check bits
        if (endBlock < blockLen && (block = mBlocks[endBlock])) {
            start = endBlock << BLOCK_INDEX_SHIFT;
            end = aEnd;
            for (i = start; i <= end; i++) {
                if ((block->mBits[(i>>3) & (BLOCK_SIZE - 1)]) & (1 << (i & 0x7)))
                    return PR_TRUE;
            }
        }
        
        return PR_FALSE;
    }
    
    void set(PRUint32 aIndex) {
        PRUint32 blockIndex = aIndex/BLOCK_SIZE_BITS;
        if (blockIndex >= mBlocks.Length()) {
            nsAutoPtr<Block> *blocks = mBlocks.AppendElements(blockIndex + 1 - mBlocks.Length());
            if (NS_UNLIKELY(!blocks)) // OOM
                return;
        }
        Block *block = mBlocks[blockIndex];
        if (!block) {
            block = new Block;
            if (NS_UNLIKELY(!block)) // OOM
                return;
            mBlocks[blockIndex] = block;
        }
        block->mBits[(aIndex>>3) & (BLOCK_SIZE - 1)] |= 1 << (aIndex & 0x7);
    }

    void set(PRUint32 aIndex, PRBool aValue) {
        if (aValue)
            set(aIndex);
        else
            clear(aIndex);
    }

    void SetRange(PRUint32 aStart, PRUint32 aEnd) {
        const PRUint32 startIndex = aStart/BLOCK_SIZE_BITS;
        const PRUint32 endIndex = aEnd/BLOCK_SIZE_BITS;

        if (endIndex >= mBlocks.Length()) {
            PRUint32 numNewBlocks = endIndex + 1 - mBlocks.Length();
            nsAutoPtr<Block> *blocks = mBlocks.AppendElements(numNewBlocks);
            if (NS_UNLIKELY(!blocks)) // OOM
                return;
        }

        for (PRUint32 i = startIndex; i <= endIndex; ++i) {
            const PRUint32 blockFirstBit = i * BLOCK_SIZE_BITS;
            const PRUint32 blockLastBit = blockFirstBit + BLOCK_SIZE_BITS - 1;

            Block *block = mBlocks[i];
            if (!block) {
                PRBool fullBlock = PR_FALSE;
                if (aStart <= blockFirstBit && aEnd >= blockLastBit)
                    fullBlock = PR_TRUE;

                block = new Block(fullBlock ? 0xFF : 0);

                if (NS_UNLIKELY(!block)) // OOM
                    return;
                mBlocks[i] = block;

                if (fullBlock)
                    continue;
            }

            const PRUint32 start = aStart > blockFirstBit ? aStart - blockFirstBit : 0;
            const PRUint32 end = PR_MIN(aEnd - blockFirstBit, BLOCK_SIZE_BITS - 1);

            for (PRUint32 bit = start; bit <= end; ++bit) {
                block->mBits[bit>>3] |= 1 << (bit & 0x7);
            }
        }
    }

    void clear(PRUint32 aIndex) {
        PRUint32 blockIndex = aIndex/BLOCK_SIZE_BITS;
        if (blockIndex >= mBlocks.Length()) {
            nsAutoPtr<Block> *blocks = mBlocks.AppendElements(blockIndex + 1 - mBlocks.Length());
            if (NS_UNLIKELY(!blocks)) // OOM
                return;
        }
        Block *block = mBlocks[blockIndex];
        if (!block) {
            return;
        }
        block->mBits[(aIndex>>3) & (BLOCK_SIZE - 1)] &= ~(1 << (aIndex & 0x7));
    }

    void ClearRange(PRUint32 aStart, PRUint32 aEnd) {
        const PRUint32 startIndex = aStart/BLOCK_SIZE_BITS;
        const PRUint32 endIndex = aEnd/BLOCK_SIZE_BITS;

        if (endIndex >= mBlocks.Length()) {
            PRUint32 numNewBlocks = endIndex + 1 - mBlocks.Length();
            nsAutoPtr<Block> *blocks = mBlocks.AppendElements(numNewBlocks);
            if (NS_UNLIKELY(!blocks)) // OOM
                return;
        }

        for (PRUint32 i = startIndex; i <= endIndex; ++i) {
            const PRUint32 blockFirstBit = i * BLOCK_SIZE_BITS;

            Block *block = mBlocks[i];
            if (!block) {
                // any nonexistent block is implicitly all clear,
                // so there's no need to even create it
                continue;
            }

            const PRUint32 start = aStart > blockFirstBit ? aStart - blockFirstBit : 0;
            const PRUint32 end = PR_MIN(aEnd - blockFirstBit, BLOCK_SIZE_BITS - 1);

            for (PRUint32 bit = start; bit <= end; ++bit) {
                block->mBits[bit>>3] &= ~(1 << (bit & 0x7));
            }
        }
    }

    PRUint32 GetSize() {
        PRUint32 size = 0;
        for (PRUint32 i = 0; i < mBlocks.Length(); i++) {
            if (mBlocks[i])
                size += sizeof(Block);
            size += sizeof(nsAutoPtr<Block>);
        }
        return size;
    }

    // clear out all blocks in the array
    void reset() {
        PRUint32 i;
        for (i = 0; i < mBlocks.Length(); i++)
            mBlocks[i] = nsnull;    
    }
    
    nsTArray< nsAutoPtr<Block> > mBlocks;
};

#define TRUETYPE_TAG(a, b, c, d) ((a) << 24 | (b) << 16 | (c) << 8 | (d))

namespace mozilla {

// Byte-swapping types and name table structure definitions moved from
// gfxFontUtils.cpp to .h file so that gfxFont.cpp can also refer to them
#pragma pack(1)

struct AutoSwap_PRUint16 {
#ifdef __SUNPRO_CC
    AutoSwap_PRUint16& operator = (const PRUint16 aValue)
      { this->value = NS_SWAP16(aValue); return *this; }
#else
    AutoSwap_PRUint16(PRUint16 aValue) { value = NS_SWAP16(aValue); }
#endif
    operator PRUint16() const { return NS_SWAP16(value); }
    operator PRUint32() const { return NS_SWAP16(value); }
    operator PRUint64() const { return NS_SWAP16(value); }
    PRUint16 value;
};

struct AutoSwap_PRInt16 {
#ifdef __SUNPRO_CC
    AutoSwap_PRInt16& operator = (const PRInt16 aValue)
      { this->value = NS_SWAP16(aValue); return *this; }
#else
    AutoSwap_PRInt16(PRInt16 aValue) { value = NS_SWAP16(aValue); }
#endif
    operator PRInt16() const { return NS_SWAP16(value); }
    operator PRUint32() const { return NS_SWAP16(value); }
    PRInt16  value;
};

struct AutoSwap_PRUint32 {
#ifdef __SUNPRO_CC
    AutoSwap_PRUint32& operator = (const PRUint32 aValue)
      { this->value = NS_SWAP32(aValue); return *this; }
#else
    AutoSwap_PRUint32(PRUint32 aValue) { value = NS_SWAP32(aValue); }
#endif
    operator PRUint32() const { return NS_SWAP32(value); }
    PRUint32  value;
};

struct AutoSwap_PRInt32 {
#ifdef __SUNPRO_CC
    AutoSwap_PRInt32& operator = (const PRInt32 aValue)
      { this->value = NS_SWAP32(aValue); return *this; }
#else
    AutoSwap_PRInt32(PRInt32 aValue) { value = NS_SWAP32(aValue); }
#endif
    operator PRInt32() const { return NS_SWAP32(value); }
    PRInt32  value;
};

struct AutoSwap_PRUint64 {
#ifdef __SUNPRO_CC
    AutoSwap_PRUint64& operator = (const PRUint64 aValue)
      { this->value = NS_SWAP64(aValue); return *this; }
#else
    AutoSwap_PRUint64(PRUint64 aValue) { value = NS_SWAP64(aValue); }
#endif
    operator PRUint64() const { return NS_SWAP64(value); }
    PRUint64  value;
};

struct AutoSwap_PRUint24 {
    operator PRUint32() const { return value[0] << 16 | value[1] << 8 | value[2]; }
private:
    AutoSwap_PRUint24() { }
    PRUint8  value[3];
};

struct SFNTHeader {
    AutoSwap_PRUint32    sfntVersion;            // Fixed, 0x00010000 for version 1.0.
    AutoSwap_PRUint16    numTables;              // Number of tables.
    AutoSwap_PRUint16    searchRange;            // (Maximum power of 2 <= numTables) x 16.
    AutoSwap_PRUint16    entrySelector;          // Log2(maximum power of 2 <= numTables).
    AutoSwap_PRUint16    rangeShift;             // NumTables x 16-searchRange.        
};

struct TableDirEntry {
    AutoSwap_PRUint32    tag;                    // 4 -byte identifier.
    AutoSwap_PRUint32    checkSum;               // CheckSum for this table.
    AutoSwap_PRUint32    offset;                 // Offset from beginning of TrueType font file.
    AutoSwap_PRUint32    length;                 // Length of this table.        
};

struct HeadTable {
    enum {
        HEAD_VERSION = 0x00010000,
        HEAD_MAGIC_NUMBER = 0x5F0F3CF5,
        HEAD_CHECKSUM_CALC_CONST = 0xB1B0AFBA
    };

    AutoSwap_PRUint32    tableVersionNumber;    // Fixed, 0x00010000 for version 1.0.
    AutoSwap_PRUint32    fontRevision;          // Set by font manufacturer.
    AutoSwap_PRUint32    checkSumAdjustment;    // To compute: set it to 0, sum the entire font as ULONG, then store 0xB1B0AFBA - sum.
    AutoSwap_PRUint32    magicNumber;           // Set to 0x5F0F3CF5.
    AutoSwap_PRUint16    flags;
    AutoSwap_PRUint16    unitsPerEm;            // Valid range is from 16 to 16384. This value should be a power of 2 for fonts that have TrueType outlines.
    AutoSwap_PRUint64    created;               // Number of seconds since 12:00 midnight, January 1, 1904. 64-bit integer
    AutoSwap_PRUint64    modified;              // Number of seconds since 12:00 midnight, January 1, 1904. 64-bit integer
    AutoSwap_PRInt16     xMin;                  // For all glyph bounding boxes.
    AutoSwap_PRInt16     yMin;                  // For all glyph bounding boxes.
    AutoSwap_PRInt16     xMax;                  // For all glyph bounding boxes.
    AutoSwap_PRInt16     yMax;                  // For all glyph bounding boxes.
    AutoSwap_PRUint16    macStyle;              // Bit 0: Bold (if set to 1);
    AutoSwap_PRUint16    lowestRecPPEM;         // Smallest readable size in pixels.
    AutoSwap_PRInt16     fontDirectionHint;
    AutoSwap_PRInt16     indexToLocFormat;
    AutoSwap_PRInt16     glyphDataFormat;
};

struct OS2Table {
    AutoSwap_PRUint16    version;                // 0004 = OpenType 1.5
    AutoSwap_PRInt16     xAvgCharWidth;
    AutoSwap_PRUint16    usWeightClass;
    AutoSwap_PRUint16    usWidthClass;
    AutoSwap_PRUint16    fsType;
    AutoSwap_PRInt16     ySubscriptXSize;
    AutoSwap_PRInt16     ySubscriptYSize;
    AutoSwap_PRInt16     ySubscriptXOffset;
    AutoSwap_PRInt16     ySubscriptYOffset;
    AutoSwap_PRInt16     ySuperscriptXSize;
    AutoSwap_PRInt16     ySuperscriptYSize;
    AutoSwap_PRInt16     ySuperscriptXOffset;
    AutoSwap_PRInt16     ySuperscriptYOffset;
    AutoSwap_PRInt16     yStrikeoutSize;
    AutoSwap_PRInt16     yStrikeoutPosition;
    AutoSwap_PRInt16     sFamilyClass;
    PRUint8              panose[10];
    AutoSwap_PRUint32    unicodeRange1;
    AutoSwap_PRUint32    unicodeRange2;
    AutoSwap_PRUint32    unicodeRange3;
    AutoSwap_PRUint32    unicodeRange4;
    PRUint8              achVendID[4];
    AutoSwap_PRUint16    fsSelection;
    AutoSwap_PRUint16    usFirstCharIndex;
    AutoSwap_PRUint16    usLastCharIndex;
    AutoSwap_PRInt16     sTypoAscender;
    AutoSwap_PRInt16     sTypoDescender;
    AutoSwap_PRInt16     sTypoLineGap;
    AutoSwap_PRUint16    usWinAscent;
    AutoSwap_PRUint16    usWinDescent;
    AutoSwap_PRUint32    codePageRange1;
    AutoSwap_PRUint32    codePageRange2;
    AutoSwap_PRInt16     sxHeight;
    AutoSwap_PRInt16     sCapHeight;
    AutoSwap_PRUint16    usDefaultChar;
    AutoSwap_PRUint16    usBreakChar;
    AutoSwap_PRUint16    usMaxContext;
};

struct PostTable {
    AutoSwap_PRUint32    version;
    AutoSwap_PRInt32     italicAngle;
    AutoSwap_PRInt16     underlinePosition;
    AutoSwap_PRUint16    underlineThickness;
    AutoSwap_PRUint32    isFixedPitch;
    AutoSwap_PRUint32    minMemType42;
    AutoSwap_PRUint32    maxMemType42;
    AutoSwap_PRUint32    minMemType1;
    AutoSwap_PRUint32    maxMemType1;
};

struct HheaTable {
    AutoSwap_PRUint32    version;
    AutoSwap_PRInt16     ascender;
    AutoSwap_PRInt16     descender;
    AutoSwap_PRInt16     lineGap;
    AutoSwap_PRUint16    advanceWidthMax;
    AutoSwap_PRInt16     minLeftSideBearing;
    AutoSwap_PRInt16     minRightSideBearing;
    AutoSwap_PRInt16     xMaxExtent;
    AutoSwap_PRInt16     caretSlopeRise;
    AutoSwap_PRInt16     caretSlopeRun;
    AutoSwap_PRInt16     caretOffset;
    AutoSwap_PRInt16     reserved1;
    AutoSwap_PRInt16     reserved2;
    AutoSwap_PRInt16     reserved3;
    AutoSwap_PRInt16     reserved4;
    AutoSwap_PRInt16     metricDataFormat;
    AutoSwap_PRUint16    numOfLongHorMetrics;
};

struct MaxpTableHeader {
    AutoSwap_PRUint32    version; // CFF: 0x00005000; TrueType: 0x00010000
    AutoSwap_PRUint16    numGlyphs;
// truetype version has additional fields that we don't currently use
};

// old 'kern' table, supported on Windows
// see http://www.microsoft.com/typography/otspec/kern.htm
struct KernTableVersion0 {
    AutoSwap_PRUint16    version; // 0x0000
    AutoSwap_PRUint16    nTables;
};

struct KernTableSubtableHeaderVersion0 {
    AutoSwap_PRUint16    version;
    AutoSwap_PRUint16    length;
    AutoSwap_PRUint16    coverage;
};

// newer Mac-only 'kern' table, ignored by Windows
// see http://developer.apple.com/textfonts/TTRefMan/RM06/Chap6kern.html
struct KernTableVersion1 {
    AutoSwap_PRUint32    version; // 0x00010000
    AutoSwap_PRUint32    nTables;
};

struct KernTableSubtableHeaderVersion1 {
    AutoSwap_PRUint32    length;
    AutoSwap_PRUint16    coverage;
    AutoSwap_PRUint16    tupleIndex;
};

#pragma pack()

// Return just the highest bit of the given value, i.e., the highest
// power of 2 that is <= value, or zero if the input value is zero.
inline PRUint32
FindHighestBit(PRUint32 value)
{
    // propagate highest bit into all lower bits of the value
    value |= (value >> 1);
    value |= (value >> 2);
    value |= (value >> 4);
    value |= (value >> 8);
    value |= (value >> 16);
    // isolate the leftmost bit
    return (value & ~(value >> 1));
}

} // namespace mozilla

// used for overlaying name changes without touching original font data
struct FontDataOverlay {
    // overlaySrc != 0 ==> use overlay
    PRUint32  overlaySrc;    // src offset from start of font data
    PRUint32  overlaySrcLen; // src length
    PRUint32  overlayDest;   // dest offset from start of font data
};
    
enum gfxUserFontType {
    GFX_USERFONT_UNKNOWN = 0,
    GFX_USERFONT_OPENTYPE = 1,
    GFX_USERFONT_SVG = 2,
    GFX_USERFONT_WOFF = 3
};

class THEBES_API gfxFontUtils {

public:
    // these are public because gfxFont.cpp also looks into the name table
    enum {
        NAME_ID_FAMILY = 1,
        NAME_ID_STYLE = 2,
        NAME_ID_UNIQUE = 3,
        NAME_ID_FULL = 4,
        NAME_ID_VERSION = 5,
        NAME_ID_POSTSCRIPT = 6,
        NAME_ID_PREFERRED_FAMILY = 16,
        NAME_ID_PREFERRED_STYLE = 17,

        PLATFORM_ALL = -1,
        PLATFORM_ID_UNICODE = 0,           // Mac OS uses this typically
        PLATFORM_ID_MAC = 1,
        PLATFORM_ID_ISO = 2,
        PLATFORM_ID_MICROSOFT = 3,

        ENCODING_ID_MAC_ROMAN = 0,         // traditional Mac OS script manager encodings
        ENCODING_ID_MAC_JAPANESE = 1,      // (there are others defined, but some were never
        ENCODING_ID_MAC_TRAD_CHINESE = 2,  // implemented by Apple, and I have never seen them
        ENCODING_ID_MAC_KOREAN = 3,        // used in font names)
        ENCODING_ID_MAC_ARABIC = 4,
        ENCODING_ID_MAC_HEBREW = 5,
        ENCODING_ID_MAC_GREEK = 6,
        ENCODING_ID_MAC_CYRILLIC = 7,
        ENCODING_ID_MAC_DEVANAGARI = 9,
        ENCODING_ID_MAC_GURMUKHI = 10,
        ENCODING_ID_MAC_GUJARATI = 11,
        ENCODING_ID_MAC_SIMP_CHINESE = 25,

        ENCODING_ID_MICROSOFT_SYMBOL = 0,  // Microsoft platform encoding IDs
        ENCODING_ID_MICROSOFT_UNICODEBMP = 1,
        ENCODING_ID_MICROSOFT_SHIFTJIS = 2,
        ENCODING_ID_MICROSOFT_PRC = 3,
        ENCODING_ID_MICROSOFT_BIG5 = 4,
        ENCODING_ID_MICROSOFT_WANSUNG = 5,
        ENCODING_ID_MICROSOFT_JOHAB  = 6,
        ENCODING_ID_MICROSOFT_UNICODEFULL = 10,

        LANG_ALL = -1,
        LANG_ID_MAC_ENGLISH = 0,      // many others are defined, but most don't affect
        LANG_ID_MAC_HEBREW = 10,      // the charset; should check all the central/eastern
        LANG_ID_MAC_JAPANESE = 11,    // european codes, though
        LANG_ID_MAC_ARABIC = 12,
        LANG_ID_MAC_ICELANDIC = 15,
        LANG_ID_MAC_TURKISH = 17,
        LANG_ID_MAC_TRAD_CHINESE = 19,
        LANG_ID_MAC_URDU = 20,
        LANG_ID_MAC_KOREAN = 23,
        LANG_ID_MAC_POLISH = 25,
        LANG_ID_MAC_FARSI = 31,
        LANG_ID_MAC_SIMP_CHINESE = 33,
        LANG_ID_MAC_ROMANIAN = 37,
        LANG_ID_MAC_CZECH = 38,
        LANG_ID_MAC_SLOVAK = 39,

        LANG_ID_MICROSOFT_EN_US = 0x0409,        // with Microsoft platformID, EN US lang code
        
        CMAP_MAX_CODEPOINT = 0x10ffff     // maximum possible Unicode codepoint 
                                          // contained in a cmap
    };

    // name table has a header, followed by name records, followed by string data
    struct NameHeader {
        mozilla::AutoSwap_PRUint16    format;       // Format selector (=0).
        mozilla::AutoSwap_PRUint16    count;        // Number of name records.
        mozilla::AutoSwap_PRUint16    stringOffset; // Offset to start of string storage
                                                    // (from start of table)
    };

    struct NameRecord {
        mozilla::AutoSwap_PRUint16    platformID;   // Platform ID
        mozilla::AutoSwap_PRUint16    encodingID;   // Platform-specific encoding ID
        mozilla::AutoSwap_PRUint16    languageID;   // Language ID
        mozilla::AutoSwap_PRUint16    nameID;       // Name ID.
        mozilla::AutoSwap_PRUint16    length;       // String length (in bytes).
        mozilla::AutoSwap_PRUint16    offset;       // String offset from start of storage
                                                    // (in bytes).
    };

    // for reading big-endian font data on either big or little-endian platforms

    static inline PRUint16
    ReadShortAt(const PRUint8 *aBuf, PRUint32 aIndex)
    {
        return (aBuf[aIndex] << 8) | aBuf[aIndex + 1];
    }

    static inline PRUint16
    ReadShortAt16(const PRUint16 *aBuf, PRUint32 aIndex)
    {
        const PRUint8 *buf = reinterpret_cast<const PRUint8*>(aBuf);
        PRUint32 index = aIndex << 1;
        return (buf[index] << 8) | buf[index+1];
    }

    static inline PRUint32
    ReadUint24At(const PRUint8 *aBuf, PRUint32 aIndex)
    {
        return ((aBuf[aIndex] << 16) | (aBuf[aIndex + 1] << 8) |
                (aBuf[aIndex + 2]));
    }

    static inline PRUint32
    ReadLongAt(const PRUint8 *aBuf, PRUint32 aIndex)
    {
        return ((aBuf[aIndex] << 24) | (aBuf[aIndex + 1] << 16) | 
                (aBuf[aIndex + 2] << 8) | (aBuf[aIndex + 3]));
    }

    static nsresult
    ReadCMAPTableFormat12(const PRUint8 *aBuf, PRUint32 aLength, 
                          gfxSparseBitSet& aCharacterMap);

    static nsresult 
    ReadCMAPTableFormat4(const PRUint8 *aBuf, PRUint32 aLength, 
                         gfxSparseBitSet& aCharacterMap);

    static nsresult
    ReadCMAPTableFormat14(const PRUint8 *aBuf, PRUint32 aLength, 
                          PRUint8*& aTable);

    static PRUint32
    FindPreferredSubtable(const PRUint8 *aBuf, PRUint32 aBufLength,
                          PRUint32 *aTableOffset, PRUint32 *aUVSTableOffset,
                          PRBool *aSymbolEncoding);

    static nsresult
    ReadCMAP(const PRUint8 *aBuf, PRUint32 aBufLength,
             gfxSparseBitSet& aCharacterMap,
             PRUint32& aUVSOffset,
             PRPackedBool& aUnicodeFont, PRPackedBool& aSymbolFont);

    static PRUint32
    MapCharToGlyphFormat4(const PRUint8 *aBuf, PRUnichar aCh);

    static PRUint32
    MapCharToGlyphFormat12(const PRUint8 *aBuf, PRUint32 aCh);

    static PRUint16
    MapUVSToGlyphFormat14(const PRUint8 *aBuf, PRUint32 aCh, PRUint32 aVS);

    static PRUint32
    MapCharToGlyph(const PRUint8 *aBuf, PRUint32 aBufLength, PRUint32 aCh);

#ifdef XP_WIN

    // given a TrueType/OpenType data file, produce a EOT-format header
    // for use with Windows T2Embed API AddFontResource type API's
    // effectively hide existing fonts with matching names aHeaderLen is
    // the size of the header buffer on input, the actual size of the
    // EOT header on output
    static nsresult
    MakeEOTHeader(const PRUint8 *aFontData, PRUint32 aFontDataLength,
                  FallibleTArray<PRUint8> *aHeader, FontDataOverlay *aOverlay);

    // determine whether a font (which has already passed ValidateSFNTHeaders)
    // is CFF format rather than TrueType
    static PRBool
    IsCffFont(const PRUint8* aFontData);

#endif

    // determine the format of font data
    static gfxUserFontType
    DetermineFontDataType(const PRUint8 *aFontData, PRUint32 aFontDataLength);

    // checks for valid SFNT table structure, returns true if valid
    // does *not* guarantee that all font data is valid
    static PRBool
    ValidateSFNTHeaders(const PRUint8 *aFontData, PRUint32 aFontDataLength);
    
    // create a new name table and build a new font with that name table
    // appended on the end, returns true on success
    static nsresult
    RenameFont(const nsAString& aName, const PRUint8 *aFontData, 
               PRUint32 aFontDataLength, FallibleTArray<PRUint8> *aNewFont);
    
    // read all names matching aNameID, returning in aNames array
    static nsresult
    ReadNames(FallibleTArray<PRUint8>& aNameTable, PRUint32 aNameID, 
              PRInt32 aPlatformID, nsTArray<nsString>& aNames);
      
    // reads English or first name matching aNameID, returning in aName
    // platform based on OS
    static nsresult
    ReadCanonicalName(FallibleTArray<PRUint8>& aNameTable, PRUint32 aNameID, 
                      nsString& aName);
      
    // convert a name from the raw name table data into an nsString,
    // provided we know how; return PR_TRUE if successful, or PR_FALSE
    // if we can't handle the encoding
    static PRBool
    DecodeFontName(const PRUint8 *aBuf, PRInt32 aLength, 
                   PRUint32 aPlatformCode, PRUint32 aScriptCode,
                   PRUint32 aLangCode, nsAString& dest);

    static inline bool IsJoinCauser(PRUint32 ch) {
        return (ch == 0x200D);
    }

    enum {
        kUnicodeVS1 = 0xFE00,
        kUnicodeVS16 = 0xFE0F,
        kUnicodeVS17 = 0xE0100,
        kUnicodeVS256 = 0xE01EF
    };

    static inline bool IsVarSelector(PRUint32 ch) {
        return (ch >= kUnicodeVS1 && ch <= kUnicodeVS16) ||
               (ch >= kUnicodeVS17 && ch <= kUnicodeVS256);
    }

    static inline bool IsInvalid(PRUint32 ch) {
        return (ch == 0xFFFD);
    }

    // Font code may want to know if there is the potential for bidi behavior
    // to be triggered by any of the characters in a text run; this can be
    // used to test that possibility.
    enum {
        kUnicodeBidiScriptsStart = 0x0590,
        kUnicodeBidiScriptsEnd = 0x08FF,
        kUnicodeBidiPresentationStart = 0xFB1D,
        kUnicodeBidiPresentationEnd = 0xFEFC,
        kUnicodeFirstHighSurrogateBlock = 0xD800,
        kUnicodeRLM = 0x200F,
        kUnicodeRLE = 0x202B,
        kUnicodeRLO = 0x202E
    };

    static inline PRBool PotentialRTLChar(PRUnichar aCh) {
        if (aCh >= kUnicodeBidiScriptsStart && aCh <= kUnicodeBidiScriptsEnd)
            // bidi scripts Hebrew, Arabic, Syriac, Thaana, N'Ko are all encoded together
            return PR_TRUE;

        if (aCh == kUnicodeRLM || aCh == kUnicodeRLE || aCh == kUnicodeRLO)
            // directional controls that trigger bidi layout
            return PR_TRUE;

        if (aCh >= kUnicodeBidiPresentationStart &&
            aCh <= kUnicodeBidiPresentationEnd)
            // presentation forms of Arabic and Hebrew letters
            return PR_TRUE;

        if ((aCh & 0xFF00) == kUnicodeFirstHighSurrogateBlock)
            // surrogate that could be part of a bidi supplementary char
            // (Cypriot, Aramaic, Phoenecian, etc)
            return PR_TRUE;

        // otherwise we know this char cannot trigger bidi reordering
        return PR_FALSE;
    }

    static PRUint8 CharRangeBit(PRUint32 ch);
    
    // for a given font list pref name, set up a list of font names
    static void GetPrefsFontList(const char *aPrefName, 
                                 nsTArray<nsString>& aFontList);

    // generate a unique font name
    static nsresult MakeUniqueUserFontName(nsAString& aName);

protected:
    static nsresult
    ReadNames(FallibleTArray<PRUint8>& aNameTable, PRUint32 aNameID, 
              PRInt32 aLangID, PRInt32 aPlatformID, nsTArray<nsString>& aNames);

    // convert opentype name-table platform/encoding/language values to a charset name
    // we can use to convert the name data to unicode, or "" if data is UTF16BE
    static const char*
    GetCharsetForFontName(PRUint16 aPlatform, PRUint16 aScript, PRUint16 aLanguage);

    struct MacFontNameCharsetMapping {
        PRUint16    mEncoding;
        PRUint16    mLanguage;
        const char *mCharsetName;

        bool operator<(const MacFontNameCharsetMapping& rhs) const {
            return (mEncoding < rhs.mEncoding) ||
                   ((mEncoding == rhs.mEncoding) && (mLanguage < rhs.mLanguage));
        }
    };
    static const MacFontNameCharsetMapping gMacFontNameCharsets[];
    static const char* gISOFontNameCharsets[];
    static const char* gMSFontNameCharsets[];
};

// helper class for loading in font info spaced out at regular intervals

class gfxFontInfoLoader {
public:

    // state transitions:
    //   initial ---StartLoader with delay---> timer on delay
    //   initial ---StartLoader without delay---> timer on interval
    //   timer on delay ---LoaderTimerFire---> timer on interval
    //   timer on delay ---CancelLoader---> timer off
    //   timer on interval ---CancelLoader---> timer off
    //   timer off ---StartLoader with delay---> timer on delay
    //   timer off ---StartLoader without delay---> timer on interval
    typedef enum {
        stateInitial,
        stateTimerOnDelay,
        stateTimerOnInterval,
        stateTimerOff
    } TimerState;

    gfxFontInfoLoader() :
        mInterval(0), mState(stateInitial)
    {
    }

    virtual ~gfxFontInfoLoader() {}

    // start timer with an initial delay, then call Run method at regular intervals
    void StartLoader(PRUint32 aDelay, PRUint32 aInterval) {
        mInterval = aInterval;

        // sanity check
        if (mState != stateInitial && mState != stateTimerOff)
            CancelLoader();

        // set up timer
        if (!mTimer) {
            mTimer = do_CreateInstance("@mozilla.org/timer;1");
            if (!mTimer) {
                NS_WARNING("Failure to create font info loader timer");
                return;
            }
        }

        // need an initial delay?
        PRUint32 timerInterval;

        if (aDelay) {
            mState = stateTimerOnDelay;
            timerInterval = aDelay;
        } else {
            mState = stateTimerOnInterval;
            timerInterval = mInterval;
        }

        InitLoader();

        // start timer
        mTimer->InitWithFuncCallback(LoaderTimerCallback, this, aDelay, 
                                     nsITimer::TYPE_REPEATING_SLACK);
    }

    // cancel the timer and cleanup
    void CancelLoader() {
        if (mState == stateInitial)
            return;
        mState = stateTimerOff;
        if (mTimer) {
            mTimer->Cancel();
        }
        FinishLoader();
    }

protected:

    // Init - initialization at start time after initial delay
    virtual void InitLoader() = 0;

    // Run - called at intervals, return true to indicate done
    virtual PRBool RunLoader() = 0;

    // Finish - cleanup after done
    virtual void FinishLoader() = 0;

    static void LoaderTimerCallback(nsITimer *aTimer, void *aThis) {
        gfxFontInfoLoader *loader = static_cast<gfxFontInfoLoader*>(aThis);
        loader->LoaderTimerFire();
    }

    // start the timer, interval callbacks
    void LoaderTimerFire() {
        if (mState == stateTimerOnDelay) {
            mState = stateTimerOnInterval;
            mTimer->SetDelay(mInterval);
        }

        PRBool done = RunLoader();
        if (done) {
            CancelLoader();
        }
    }

    nsCOMPtr<nsITimer> mTimer;
    PRUint32 mInterval;
    TimerState mState;
};

#endif /* GFX_FONT_UTILS_H */