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 (409f3966645a)

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
/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef GFX_USER_FONT_SET_H
#define GFX_USER_FONT_SET_H

#include "gfxFont.h"
#include "gfxFontFamilyList.h"
#include "gfxFontSrcPrincipal.h"
#include "gfxFontSrcURI.h"
#include "nsRefPtrHashtable.h"
#include "nsCOMPtr.h"
#include "nsIURI.h"
#include "nsIPrincipal.h"
#include "nsIScriptError.h"
#include "nsURIHashKey.h"
#include "mozilla/FontPropertyTypes.h"
#include "mozilla/net/ReferrerPolicy.h"
#include "gfxFontConstants.h"

namespace mozilla {
class PostTraversalTask;
} // namespace mozilla
class nsFontFaceLoader;

//#define DEBUG_USERFONT_CACHE

class gfxFontFaceBufferSource
{
  NS_INLINE_DECL_REFCOUNTING(gfxFontFaceBufferSource)
public:
  virtual void TakeBuffer(uint8_t*& aBuffer, uint32_t& aLength) = 0;

protected:
  virtual ~gfxFontFaceBufferSource() {}
};

// parsed CSS @font-face rule information
// lifetime: from when @font-face rule processed until font is loaded
struct gfxFontFaceSrc {

    enum SourceType {
        eSourceType_Local,
        eSourceType_URL,
        eSourceType_Buffer
    };

    SourceType             mSourceType;

    // if url, whether to use the origin principal or not
    bool                   mUseOriginPrincipal;

    // format hint flags, union of all possible formats
    // (e.g. TrueType, EOT, SVG, etc.)
    // see FLAG_FORMAT_* enum values below
    uint32_t               mFormatFlags;

    nsString               mLocalName;     // full font name if local
    RefPtr<gfxFontSrcURI>  mURI;           // uri if url
    nsCOMPtr<nsIURI>       mReferrer;      // referrer url if url
    mozilla::net::ReferrerPolicy mReferrerPolicy;
    RefPtr<gfxFontSrcPrincipal> mOriginPrincipal; // principal if url

    RefPtr<gfxFontFaceBufferSource> mBuffer;

    // The principal that should be used for the load. Should only be used for
    // URL sources.
    gfxFontSrcPrincipal* LoadPrincipal(const gfxUserFontSet&) const;
};

inline bool
operator==(const gfxFontFaceSrc& a, const gfxFontFaceSrc& b)
{
    // The mReferrer and mOriginPrincipal comparisons aren't safe OMT.
    MOZ_ASSERT(NS_IsMainThread());

    if (a.mSourceType != b.mSourceType) {
        return false;
    }
    switch (a.mSourceType) {
        case gfxFontFaceSrc::eSourceType_Local:
            return a.mLocalName == b.mLocalName;
        case gfxFontFaceSrc::eSourceType_URL: {
            bool equals;
            return a.mUseOriginPrincipal == b.mUseOriginPrincipal &&
                   a.mFormatFlags == b.mFormatFlags &&
                   (a.mURI == b.mURI || a.mURI->Equals(b.mURI)) &&
                   NS_SUCCEEDED(a.mReferrer->Equals(b.mReferrer, &equals)) &&
                     equals &&
                   a.mReferrerPolicy == b.mReferrerPolicy &&
                   a.mOriginPrincipal->Equals(b.mOriginPrincipal);
        }
        case gfxFontFaceSrc::eSourceType_Buffer:
            return a.mBuffer == b.mBuffer;
    }
    NS_WARNING("unexpected mSourceType");
    return false;
}

// Subclassed to store platform-specific code cleaned out when font entry is
// deleted.
// Lifetime: from when platform font is created until it is deactivated.
// If the platform does not need to add any platform-specific code/data here,
// then the gfxUserFontSet will allocate a base gfxUserFontData and attach
// to the entry to track the basic user font info fields here.
class gfxUserFontData {
public:
    gfxUserFontData()
        : mSrcIndex(0), mFormat(0), mMetaOrigLen(0),
          mCompression(kUnknownCompression),
          mPrivate(false), mIsBuffer(false)
    { }
    virtual ~gfxUserFontData() { }

    size_t SizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) const;

    nsTArray<uint8_t> mMetadata;  // woff metadata block (compressed), if any
    RefPtr<gfxFontSrcURI>  mURI;       // URI of the source, if it was url()
    RefPtr<gfxFontSrcPrincipal> mPrincipal; // principal for the download, if url()
    nsString          mLocalName; // font name used for the source, if local()
    nsString          mRealName;  // original fullname from the font resource
    uint32_t          mSrcIndex;  // index in the rule's source list
    uint32_t          mFormat;    // format hint for the source used, if any
    uint32_t          mMetaOrigLen; // length needed to decompress metadata
    uint8_t           mCompression; // compression type
    bool              mPrivate;   // whether font belongs to a private window
    bool              mIsBuffer;  // whether the font source was a buffer

    enum {
        kUnknownCompression = 0,
        kZlibCompression = 1,
        kBrotliCompression = 2
    };
};

// initially contains a set of userfont font entry objects, replaced with
// platform/user fonts as downloaded

class gfxUserFontFamily : public gfxFontFamily {
public:
    friend class gfxUserFontSet;

    explicit gfxUserFontFamily(const nsAString& aName)
        : gfxFontFamily(aName) { }

    virtual ~gfxUserFontFamily();

    // add the given font entry to the end of the family's list
    void AddFontEntry(gfxFontEntry* aFontEntry) {
        // keep ref while removing existing entry
        RefPtr<gfxFontEntry> fe = aFontEntry;
        // remove existing entry, if already present
        mAvailableFonts.RemoveElement(aFontEntry);
        // insert at the beginning so that the last-defined font is the first
        // one in the fontlist used for matching, as per CSS Fonts spec
        mAvailableFonts.InsertElementAt(0, aFontEntry);

        if (aFontEntry->mFamilyName.IsEmpty()) {
            aFontEntry->mFamilyName = Name();
        } else {
#ifdef DEBUG
            nsString thisName = Name();
            nsString entryName = aFontEntry->mFamilyName;
            ToLowerCase(thisName);
            ToLowerCase(entryName);
            MOZ_ASSERT(thisName.Equals(entryName));
#endif
        }
        ResetCharacterMap();
    }

    // Remove all font entries from the family
    void DetachFontEntries() {
        mAvailableFonts.Clear();
    }
};

class gfxUserFontEntry;
class gfxOTSContext;

class gfxUserFontSet {
    friend class gfxUserFontEntry;
    friend class gfxOTSContext;

public:
    typedef mozilla::FontStretch FontStretch;
    typedef mozilla::StretchRange StretchRange;
    typedef mozilla::FontSlantStyle FontSlantStyle;
    typedef mozilla::SlantStyleRange SlantStyleRange;
    typedef mozilla::FontWeight FontWeight;
    typedef mozilla::WeightRange WeightRange;
    typedef gfxFontEntry::RangeFlags RangeFlags;

    NS_INLINE_DECL_THREADSAFE_REFCOUNTING(gfxUserFontSet)

    gfxUserFontSet();

    enum {
        // no flags ==> no hint set
        // unknown ==> unknown format hint set
        FLAG_FORMAT_UNKNOWN        = 1,
        FLAG_FORMAT_OPENTYPE       = 1 << 1,
        FLAG_FORMAT_TRUETYPE       = 1 << 2,
        FLAG_FORMAT_TRUETYPE_AAT   = 1 << 3,
        FLAG_FORMAT_EOT            = 1 << 4,
        FLAG_FORMAT_SVG            = 1 << 5,
        FLAG_FORMAT_WOFF           = 1 << 6,
        FLAG_FORMAT_WOFF2          = 1 << 7,

        FLAG_FORMAT_OPENTYPE_VARIATIONS = 1 << 8,
        FLAG_FORMAT_TRUETYPE_VARIATIONS = 1 << 9,
        FLAG_FORMAT_WOFF_VARIATIONS     = 1 << 10,
        FLAG_FORMAT_WOFF2_VARIATIONS    = 1 << 11,

        // the common formats that we support everywhere
        FLAG_FORMATS_COMMON        = FLAG_FORMAT_OPENTYPE |
                                     FLAG_FORMAT_TRUETYPE |
                                     FLAG_FORMAT_WOFF     |
                                     FLAG_FORMAT_WOFF2    |
                                     FLAG_FORMAT_OPENTYPE_VARIATIONS |
                                     FLAG_FORMAT_TRUETYPE_VARIATIONS |
                                     FLAG_FORMAT_WOFF_VARIATIONS     |
                                     FLAG_FORMAT_WOFF2_VARIATIONS,

        // mask of all unused bits, update when adding new formats
        FLAG_FORMAT_NOT_USED       = ~((1 << 12)-1)
    };


    // creates a font face without adding it to a particular family
    // weight - [100, 900] (multiples of 100)
    // stretch = [FontStretch::UltraCondensed(), FontStretch::UltraExpanded()]
    // italic style = constants in gfxFontConstants.h, e.g. NS_FONT_STYLE_NORMAL
    // language override = result of calling nsRuleNode::ParseFontLanguageOverride
    // TODO: support for unicode ranges not yet implemented
    virtual already_AddRefed<gfxUserFontEntry> CreateUserFontEntry(
                              const nsTArray<gfxFontFaceSrc>& aFontFaceSrcList,
                              WeightRange aWeight,
                              StretchRange aStretch,
                              SlantStyleRange aStyle,
                              const nsTArray<gfxFontFeature>& aFeatureSettings,
                              const nsTArray<gfxFontVariation>& aVariationSettings,
                              uint32_t aLanguageOverride,
                              gfxCharacterMap* aUnicodeRanges,
                              uint8_t aFontDisplay,
                              RangeFlags aRangeFlags) = 0;

    // creates a font face for the specified family, or returns an existing
    // matching entry on the family if there is one
    already_AddRefed<gfxUserFontEntry> FindOrCreateUserFontEntry(
                               const nsAString& aFamilyName,
                               const nsTArray<gfxFontFaceSrc>& aFontFaceSrcList,
                               WeightRange aWeight,
                               StretchRange aStretch,
                               SlantStyleRange aStyle,
                               const nsTArray<gfxFontFeature>& aFeatureSettings,
                               const nsTArray<gfxFontVariation>& aVariationSettings,
                               uint32_t aLanguageOverride,
                               gfxCharacterMap* aUnicodeRanges,
                               uint8_t aFontDisplay,
                               RangeFlags aRangeFlags);

    // add in a font face for which we have the gfxUserFontEntry already
    void AddUserFontEntry(const nsAString& aFamilyName,
                          gfxUserFontEntry* aUserFontEntry);

    // Whether there is a face with this family name
    bool HasFamily(const nsAString& aFamilyName) const
    {
        return LookupFamily(aFamilyName) != nullptr;
    }

    // Look up and return the gfxUserFontFamily in mFontFamilies with
    // the given name
    gfxUserFontFamily* LookupFamily(const nsAString& aName) const;

    // Look up names in a fontlist and return true if any are in the set
    bool ContainsUserFontSetFonts(const mozilla::FontFamilyList& aFontList) const;

    virtual gfxFontSrcPrincipal* GetStandardFontLoadPrincipal() const = 0;

    // check whether content policies allow the given URI to load.
    virtual bool IsFontLoadAllowed(const gfxFontFaceSrc&) = 0;

    // Dispatches all of the specified runnables to the font face set's
    // document's event queue.
    virtual void DispatchFontLoadViolations(
        nsTArray<nsCOMPtr<nsIRunnable>>& aViolations) = 0;

    // initialize the process that loads external font data, which upon
    // completion will call FontDataDownloadComplete method
    virtual nsresult StartLoad(gfxUserFontEntry* aUserFontEntry,
                               const gfxFontFaceSrc* aFontFaceSrc) = 0;

    // generation - each time a face is loaded, generation is
    // incremented so that the change can be recognized
    uint64_t GetGeneration() { return mGeneration; }

    // increment the generation on font load
    void IncrementGeneration(bool aIsRebuild = false);

    // Generation is bumped on font loads but that doesn't affect name-style
    // mappings. Rebuilds do however affect name-style mappings so need to
    // lookup fontlists again when that happens.
    uint64_t GetRebuildGeneration() { return mRebuildGeneration; }

    // rebuild if local rules have been used
    void RebuildLocalRules();

    class UserFontCache {
    public:
        // Record a loaded user-font in the cache. This requires that the
        // font-entry's userFontData has been set up already, as it relies
        // on the URI and Principal recorded there.
        static void CacheFont(gfxFontEntry* aFontEntry);

        // The given gfxFontEntry is being destroyed, so remove any record that
        // refers to it.
        static void ForgetFont(gfxFontEntry* aFontEntry);

        // Return the gfxFontEntry corresponding to a given URI and principal,
        // and the features of the given userfont entry, or nullptr if none is available.
        // The aPrivate flag is set for requests coming from private windows,
        // so we can avoid leaking fonts cached in private windows mode out to
        // normal windows.
        static gfxFontEntry* GetFont(const gfxFontFaceSrc&, const gfxUserFontEntry&);

        // Clear everything so that we don't leak URIs and Principals.
        static void Shutdown();

        // Memory-reporting support.
        class MemoryReporter final : public nsIMemoryReporter
        {
        private:
            ~MemoryReporter() { }

        public:
            NS_DECL_ISUPPORTS
            NS_DECL_NSIMEMORYREPORTER
        };

#ifdef DEBUG_USERFONT_CACHE
        // dump contents
        static void Dump();
#endif

    private:
        // Helper that we use to observe the empty-cache notification
        // from nsICacheService.
        class Flusher : public nsIObserver
        {
            virtual ~Flusher() {}
        public:
            NS_DECL_ISUPPORTS
            NS_DECL_NSIOBSERVER
            Flusher() {}
        };

        // Key used to look up entries in the user-font cache.
        // Note that key comparison does *not* use the mFontEntry field
        // as a whole; it only compares specific fields within the entry
        // (weight/width/style/features) that could affect font selection
        // or rendering, and that must match between a font-set's userfont
        // entry and the corresponding "real" font entry.
        struct Key {
            RefPtr<gfxFontSrcURI>   mURI;
            RefPtr<gfxFontSrcPrincipal> mPrincipal; // use nullptr with data: URLs
            // The font entry MUST notify the cache when it is destroyed
            // (by calling ForgetFont()).
            gfxFontEntry* MOZ_NON_OWNING_REF mFontEntry;
            bool                    mPrivate;

            Key(gfxFontSrcURI* aURI, gfxFontSrcPrincipal* aPrincipal,
                gfxFontEntry* aFontEntry, bool aPrivate)
                : mURI(aURI),
                  mPrincipal(aPrincipal),
                  mFontEntry(aFontEntry),
                  mPrivate(aPrivate)
            { }
        };

        class Entry : public PLDHashEntryHdr {
        public:
            typedef const Key& KeyType;
            typedef const Key* KeyTypePointer;

            explicit Entry(KeyTypePointer aKey)
                : mURI(aKey->mURI),
                  mPrincipal(aKey->mPrincipal),
                  mFontEntry(aKey->mFontEntry),
                  mPrivate(aKey->mPrivate)
            { }

            Entry(Entry&& aOther)
                : mURI(std::move(aOther.mURI))
                , mPrincipal(std::move(aOther.mPrincipal))
                , mFontEntry(std::move(aOther.mFontEntry))
                , mPrivate(std::move(aOther.mPrivate))
            { }

            ~Entry() { }

            bool KeyEquals(const KeyTypePointer aKey) const;

            static KeyTypePointer KeyToPointer(KeyType aKey) { return &aKey; }

            static PLDHashNumber HashKey(const KeyTypePointer aKey) {
                PLDHashNumber principalHash =
                    aKey->mPrincipal ? aKey->mPrincipal->Hash() : 0;
                return mozilla::HashGeneric(principalHash + int(aKey->mPrivate),
                                            aKey->mURI->Hash(),
                                            HashFeatures(aKey->mFontEntry->mFeatureSettings),
                                            HashVariations(aKey->mFontEntry->mVariationSettings),
                                            mozilla::HashString(aKey->mFontEntry->mFamilyName),
                                            aKey->mFontEntry->Weight().AsScalar(),
                                            aKey->mFontEntry->SlantStyle().AsScalar(),
                                            aKey->mFontEntry->Stretch().AsScalar(),
                                            aKey->mFontEntry->mLanguageOverride);
            }

            enum { ALLOW_MEMMOVE = false };

            gfxFontSrcURI* GetURI() const { return mURI; }
            gfxFontSrcPrincipal* GetPrincipal() const { return mPrincipal; }
            gfxFontEntry* GetFontEntry() const { return mFontEntry; }
            bool IsPrivate() const { return mPrivate; }

            void ReportMemory(nsIHandleReportCallback* aHandleReport,
                              nsISupports* aData, bool aAnonymize);

#ifdef DEBUG_USERFONT_CACHE
            void Dump();
#endif

        private:
            static uint32_t
            HashFeatures(const nsTArray<gfxFontFeature>& aFeatures) {
                return mozilla::HashBytes(aFeatures.Elements(),
                                          aFeatures.Length() * sizeof(gfxFontFeature));
            }

            static uint32_t
            HashVariations(const nsTArray<gfxFontVariation>& aVariations) {
                return mozilla::HashBytes(aVariations.Elements(),
                                          aVariations.Length() * sizeof(gfxFontVariation));
            }

            RefPtr<gfxFontSrcURI>  mURI;
            RefPtr<gfxFontSrcPrincipal> mPrincipal; // or nullptr for data: URLs

            // The "real" font entry corresponding to this downloaded font.
            // The font entry MUST notify the cache when it is destroyed
            // (by calling ForgetFont()).
            gfxFontEntry* MOZ_NON_OWNING_REF mFontEntry;

            // Whether this font was loaded from a private window.
            bool                   mPrivate;
        };

        static nsTHashtable<Entry>* sUserFonts;
    };

    void SetLocalRulesUsed() {
        mLocalRulesUsed = true;
    }

    static mozilla::LogModule* GetUserFontsLog();

    // record statistics about font completion
    virtual void RecordFontLoadDone(uint32_t aFontSize,
                                    mozilla::TimeStamp aDoneTime) {}

    void GetLoadStatistics(uint32_t& aLoadCount, uint64_t& aLoadSize) const {
        aLoadCount = mDownloadCount;
        aLoadSize = mDownloadSize;
    }

protected:
    // Protected destructor, to discourage deletion outside of Release():
    virtual ~gfxUserFontSet();

    // Return whether the font set is associated with a private-browsing tab.
    virtual bool GetPrivateBrowsing() = 0;

    // Return whether the font set is associated with a document that was
    // shift-reloaded, for example, and thus should bypass the font cache.
    virtual bool BypassCache() = 0;

    // parse data for a data URL
    virtual nsresult SyncLoadFontData(gfxUserFontEntry* aFontToLoad,
                                      const gfxFontFaceSrc* aFontFaceSrc,
                                      uint8_t* &aBuffer,
                                      uint32_t &aBufferLength) = 0;

    // report a problem of some kind (implemented in nsUserFontSet)
    virtual nsresult LogMessage(gfxUserFontEntry* aUserFontEntry,
                                const char* aMessage,
                                uint32_t aFlags = nsIScriptError::errorFlag,
                                nsresult aStatus = NS_OK) = 0;

    // helper method for performing the actual userfont set rebuild
    virtual void DoRebuildUserFontSet() = 0;

    // helper method for FindOrCreateUserFontEntry
    gfxUserFontEntry* FindExistingUserFontEntry(
                                   gfxUserFontFamily* aFamily,
                                   const nsTArray<gfxFontFaceSrc>& aFontFaceSrcList,
                                   WeightRange aWeight,
                                   StretchRange aStretch,
                                   SlantStyleRange aStyle,
                                   const nsTArray<gfxFontFeature>& aFeatureSettings,
                                   const nsTArray<gfxFontVariation>& aVariationSettings,
                                   uint32_t aLanguageOverride,
                                   gfxCharacterMap* aUnicodeRanges,
                                   uint8_t aFontDisplay,
                                   RangeFlags aRangeFlags);

    // creates a new gfxUserFontFamily in mFontFamilies, or returns an existing
    // family if there is one
    gfxUserFontFamily* GetFamily(const nsAString& aFamilyName);

    // font families defined by @font-face rules
    nsRefPtrHashtable<nsStringHashKey, gfxUserFontFamily> mFontFamilies;

    uint64_t        mGeneration;        // bumped on any font load change
    uint64_t        mRebuildGeneration; // only bumped on rebuilds

    // true when local names have been looked up, false otherwise
    bool mLocalRulesUsed;

    // true when rules using local names need to be redone
    bool mRebuildLocalRules;

    // performance stats
    uint32_t mDownloadCount;
    uint64_t mDownloadSize;
};

// acts a placeholder until the real font is downloaded

class gfxUserFontEntry : public gfxFontEntry {
    friend class mozilla::PostTraversalTask;
    friend class gfxUserFontSet;
    friend class nsUserFontSet;
    friend class nsFontFaceLoader;
    friend class gfxOTSContext;

public:
    enum UserFontLoadState {
        STATUS_NOT_LOADED = 0,
        STATUS_LOAD_PENDING,
        STATUS_LOADING,
        STATUS_LOADED,
        STATUS_FAILED
    };

    gfxUserFontEntry(gfxUserFontSet* aFontSet,
                     const nsTArray<gfxFontFaceSrc>& aFontFaceSrcList,
                     WeightRange aWeight,
                     StretchRange aStretch,
                     SlantStyleRange aStyle,
                     const nsTArray<gfxFontFeature>& aFeatureSettings,
                     const nsTArray<gfxFontVariation>& aVariationSettings,
                     uint32_t aLanguageOverride,
                     gfxCharacterMap* aUnicodeRanges,
                     uint8_t aFontDisplay,
                     RangeFlags aRangeFlags);

    virtual ~gfxUserFontEntry();

    // Return whether the entry matches the given list of attributes
    bool Matches(const nsTArray<gfxFontFaceSrc>& aFontFaceSrcList,
                 WeightRange aWeight,
                 StretchRange aStretch,
                 SlantStyleRange aStyle,
                 const nsTArray<gfxFontFeature>& aFeatureSettings,
                 const nsTArray<gfxFontVariation>& aVariationSettings,
                 uint32_t aLanguageOverride,
                 gfxCharacterMap* aUnicodeRanges,
                 uint8_t aFontDisplay,
                 RangeFlags aRangeFlags);

    gfxFont* CreateFontInstance(const gfxFontStyle* aFontStyle) override;

    gfxFontEntry* GetPlatformFontEntry() const { return mPlatformFontEntry; }

    // is the font loading or loaded, or did it fail?
    UserFontLoadState LoadState() const { return mUserFontLoadState; }

    void LoadCanceled()
    {
      mUserFontLoadState = STATUS_NOT_LOADED;
      mFontDataLoadingState = NOT_LOADING;
      mLoader = nullptr;
    }

    // whether to wait before using fallback font or not
    bool WaitForUserFont() const {
        return (mUserFontLoadState == STATUS_LOAD_PENDING ||
                mUserFontLoadState == STATUS_LOADING) &&
               mFontDataLoadingState < LOADING_SLOWLY;
    }

    // for userfonts, cmap is used to store the unicode range data
    // no cmap ==> all codepoints permitted
    bool CharacterInUnicodeRange(uint32_t ch) const {
        if (mCharacterMap) {
            return mCharacterMap->test(ch);
        }
        return true;
    }

    gfxCharacterMap* GetUnicodeRangeMap() const {
        return mCharacterMap.get();
    }

    uint8_t GetFontDisplay() const { return mFontDisplay; }

    // load the font - starts the loading of sources which continues until
    // a valid font resource is found or all sources fail
    void Load();

    // methods to expose some information to FontFaceSet::UserFontSet
    // since we can't make that class a friend
    void SetLoader(nsFontFaceLoader* aLoader) { mLoader = aLoader; }
    nsFontFaceLoader* GetLoader() { return mLoader; }
    gfxFontSrcPrincipal* GetPrincipal() { return mPrincipal; }
    uint32_t GetSrcIndex() { return mSrcIndex; }
    void GetFamilyNameAndURIForLogging(nsACString& aFamilyName,
                                       nsACString& aURI);

    gfxFontEntry* Clone() const override {
        MOZ_ASSERT_UNREACHABLE("cannot Clone user fonts");
        return nullptr;
    }

#ifdef DEBUG
    gfxUserFontSet* GetUserFontSet() const { return mFontSet; }
#endif

    const nsTArray<gfxFontFaceSrc>& SourceList() const
    {
      return mSrcList;
    }

    // The variation-query APIs should not be called on placeholders.
    bool HasVariations() override {
      MOZ_ASSERT_UNREACHABLE("not meaningful for a userfont placeholder");
      return false;
    }
    void GetVariationAxes(nsTArray<gfxFontVariationAxis>&) override {
      MOZ_ASSERT_UNREACHABLE("not meaningful for a userfont placeholder");
    }
    void GetVariationInstances(nsTArray<gfxFontVariationInstance>&) override {
      MOZ_ASSERT_UNREACHABLE("not meaningful for a userfont placeholder");
    }

protected:
    const uint8_t* SanitizeOpenTypeData(const uint8_t* aData,
                                        uint32_t aLength,
                                        uint32_t& aSaneLength,
                                        gfxUserFontType aFontType);

    // attempt to load the next resource in the src list.
    void LoadNextSrc();
    void ContinueLoad();
    void DoLoadNextSrc(bool aForceAsync);

    // change the load state
    virtual void SetLoadState(UserFontLoadState aLoadState);

    // when download has been completed, pass back data here
    // aDownloadStatus == NS_OK ==> download succeeded, error otherwise
    // returns true if platform font creation sucessful (or local()
    // reference was next in line)
    // Ownership of aFontData is passed in here; the font set must
    // ensure that it is eventually deleted with free().
    bool FontDataDownloadComplete(const uint8_t* aFontData, uint32_t aLength,
                                  nsresult aDownloadStatus);

    // helper method for creating a platform font
    // returns true if platform font creation successful
    // Ownership of aFontData is passed in here; the font must
    // ensure that it is eventually deleted with free().
    bool LoadPlatformFont(const uint8_t* aFontData, uint32_t& aLength);

    // store metadata and src details for current src into aFontEntry
    void StoreUserFontData(gfxFontEntry*      aFontEntry,
                           bool               aPrivate,
                           const nsAString&   aOriginalName,
                           FallibleTArray<uint8_t>* aMetadata,
                           uint32_t           aMetaOrigLen,
                           uint8_t            aCompression);

    // Clears and then adds to aResult all of the user font sets that this user
    // font entry has been added to.  This will at least include mFontSet, the
    // owner of this user font entry.
    virtual void GetUserFontSets(nsTArray<gfxUserFontSet*>& aResult);

    // Calls IncrementGeneration() on all user font sets that contain this
    // user font entry.
    void IncrementGeneration();

    // general load state
    UserFontLoadState        mUserFontLoadState;

    // detailed load state while font data is loading
    // used to determine whether to use fallback font or not
    // note that code depends on the ordering of these values!
    enum FontDataLoadingState {
        NOT_LOADING = 0,     // not started to load any font resources yet
        LOADING_STARTED,     // loading has started; hide fallback font
        LOADING_ALMOST_DONE, // timeout happened but we're nearly done,
                             // so keep hiding fallback font
        LOADING_SLOWLY,      // timeout happened and we're not nearly done,
                             // so use the fallback font
        LOADING_TIMED_OUT,   // font load took too long
        LOADING_FAILED       // failed to load any source: use fallback
    };
    FontDataLoadingState     mFontDataLoadingState;

    bool                     mUnsupportedFormat;
    uint8_t                  mFontDisplay; // timing of userfont fallback

    RefPtr<gfxFontEntry>   mPlatformFontEntry;
    nsTArray<gfxFontFaceSrc> mSrcList;
    uint32_t                 mSrcIndex; // index of loading src item
    // This field is managed by the nsFontFaceLoader. In the destructor and Cancel()
    // methods of nsFontFaceLoader this reference is nulled out.
    nsFontFaceLoader* MOZ_NON_OWNING_REF mLoader; // current loader for this entry, if any
    gfxUserFontSet*   MOZ_NON_OWNING_REF mFontSet; // font-set which owns this userfont entry
    RefPtr<gfxFontSrcPrincipal> mPrincipal;
};


#endif /* GFX_USER_FONT_SET_H */