dm/DM.cpp

/*
 * Copyright 2013 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#include "CrashHandler.h"
#include "DMJsonWriter.h"
#include "DMSrcSink.h"
#include "DMSrcSinkAndroid.h"
#include "OverwriteLine.h"
#include "ProcStats.h"
#include "SkBBHFactory.h"
#include "SkChecksum.h"
#include "SkCodec.h"
#include "SkCommonFlags.h"
#include "SkCommonFlagsConfig.h"
#include "SkFontMgr.h"
#include "SkForceLinking.h"
#include "SkGraphics.h"
#include "SkMD5.h"
#include "SkMutex.h"
#include "SkOSFile.h"
#include "SkTHash.h"
#include "SkTaskGroup.h"
#include "SkThreadUtils.h"
#include "Test.h"
#include "Timer.h"
#include "sk_tool_utils.h"

#ifdef SK_PDF_IMAGE_STATS
extern void SkPDFImageDumpStats();
#endif

#include "png.h"

#include <stdlib.h>

#ifndef SK_BUILD_FOR_WIN32
    #include <unistd.h>
#endif

DEFINE_string(src, "tests gm skp image", "Source types to test.");
DEFINE_bool(nameByHash, false,
            "If true, write to FLAGS_writePath[0]/<hash>.png instead of "
            "to FLAGS_writePath[0]/<config>/<sourceType>/<sourceOptions>/<name>.png");
DEFINE_bool2(pathOpsExtended, x, false, "Run extended pathOps tests.");
DEFINE_string(matrix, "1 0 0 1",
              "2x2 scale+skew matrix to apply or upright when using "
              "'matrix' or 'upright' in config.");
DEFINE_bool(gpu_threading, false, "Allow GPU work to run on multiple threads?");

DEFINE_string(blacklist, "",
        "Space-separated config/src/srcOptions/name quadruples to blacklist.  '_' matches anything.  E.g. \n"
        "'--blacklist gpu skp _ _' will blacklist all SKPs drawn into the gpu config.\n"
        "'--blacklist gpu skp _ _ 8888 gm _ aarects' will also blacklist the aarects GM on 8888.");

DEFINE_string2(readPath, r, "", "If set check for equality with golden results in this directory.");

DEFINE_string(uninterestingHashesFile, "",
        "File containing a list of uninteresting hashes. If a result hashes to something in "
        "this list, no image is written for that result.");

DEFINE_int32(shards, 1, "We're splitting source data into this many shards.");
DEFINE_int32(shard,  0, "Which shard do I run?");
DEFINE_bool2(pre_log, p, false, "Log before running each test. May be incomprehensible when threading");

__SK_FORCE_IMAGE_DECODER_LINKING;
using namespace DM;

/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/

static double now_ms() { return SkTime::GetNSecs() * 1e-6; }

SK_DECLARE_STATIC_MUTEX(gFailuresMutex);
static SkTArray<SkString> gFailures;

static void fail(ImplicitString err) {
    SkAutoMutexAcquire lock(gFailuresMutex);
    SkDebugf("\n\nFAILURE: %s\n\n", err.c_str());
    gFailures.push_back(err);
}

static int32_t gPending = 0;  // Atomic.  Total number of running and queued tasks.

SK_DECLARE_STATIC_MUTEX(gRunningAndTallyMutex);
static SkTArray<SkString>        gRunning;
static SkTHashMap<SkString, int> gNoteTally;

static void done(double ms,
                 ImplicitString config, ImplicitString src, ImplicitString srcOptions,
                 ImplicitString name, ImplicitString note, ImplicitString log) {
    SkString id = SkStringPrintf("%s %s %s %s", config.c_str(), src.c_str(),
                                                srcOptions.c_str(), name.c_str());
    {
        SkAutoMutexAcquire lock(gRunningAndTallyMutex);
        for (int i = 0; i < gRunning.count(); i++) {
            if (gRunning[i] == id) {
                gRunning.removeShuffle(i);
                break;
            }
        }
        if (!note.isEmpty()) {
            if (int* tally = gNoteTally.find(note)) {
                *tally += 1;
            } else {
                gNoteTally.set(note, 1);
            }
        }
    }
    if (!log.isEmpty()) {
        log.prepend("\n");
    }
    auto pending = sk_atomic_dec(&gPending)-1;
    if (!FLAGS_quiet && note.isEmpty()) {
        SkDebugf("%s(%4d/%-4dMB %6d) %s\t%s%s", FLAGS_verbose ? "\n" : kSkOverwriteLine
                                           , sk_tools::getCurrResidentSetSizeMB()
                                           , sk_tools::getMaxResidentSetSizeMB()
                                           , pending
                                           , HumanizeMs(ms).c_str()
                                           , id.c_str()
                                           , log.c_str());
    }
    // We write our dm.json file every once in a while in case we crash.
    // Notice this also handles the final dm.json when pending == 0.
    if (pending % 500 == 0) {
        JsonWriter::DumpJson();
    }
}

static void start(ImplicitString config, ImplicitString src,
                  ImplicitString srcOptions, ImplicitString name) {
    SkString id = SkStringPrintf("%s %s %s %s", config.c_str(), src.c_str(),
                                                srcOptions.c_str(), name.c_str());
    SkAutoMutexAcquire lock(gRunningAndTallyMutex);
    gRunning.push_back(id);
}

/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/

struct Gold : public SkString {
    Gold() : SkString("") {}
    Gold(ImplicitString sink, ImplicitString src, ImplicitString srcOptions,
         ImplicitString name, ImplicitString md5)
        : SkString("") {
        this->append(sink);
        this->append(src);
        this->append(srcOptions);
        this->append(name);
        this->append(md5);
    }
    struct Hash {
        uint32_t operator()(const Gold& g) const {
            return SkGoodHash()((const SkString&)g);
        }
    };
};
static SkTHashSet<Gold, Gold::Hash> gGold;

static void add_gold(JsonWriter::BitmapResult r) {
    gGold.add(Gold(r.config, r.sourceType, r.sourceOptions, r.name, r.md5));
}

static void gather_gold() {
    if (!FLAGS_readPath.isEmpty()) {
        SkString path(FLAGS_readPath[0]);
        path.append("/dm.json");
        if (!JsonWriter::ReadJson(path.c_str(), add_gold)) {
            fail(SkStringPrintf("Couldn't read %s for golden results.", path.c_str()));
        }
    }
}

/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/

static SkTHashSet<SkString> gUninterestingHashes;

static void gather_uninteresting_hashes() {
    if (!FLAGS_uninterestingHashesFile.isEmpty()) {
        SkAutoTUnref<SkData> data(SkData::NewFromFileName(FLAGS_uninterestingHashesFile[0]));
        if (!data) {
            SkDebugf("WARNING: unable to read uninteresting hashes from %s\n",
                     FLAGS_uninterestingHashesFile[0]);
            return;
        }
        SkTArray<SkString> hashes;
        SkStrSplit((const char*)data->data(), "\n", &hashes);
        for (const SkString& hash : hashes) {
            gUninterestingHashes.add(hash);
        }
    }
}

/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/

struct TaggedSrc : public SkAutoTDelete<Src> {
    ImplicitString tag;
    ImplicitString options;
};

struct TaggedSink : public SkAutoTDelete<Sink> {
    SkString tag;
};

static const bool kMemcpyOK = true;

static SkTArray<TaggedSrc,  kMemcpyOK>  gSrcs;
static SkTArray<TaggedSink, kMemcpyOK> gSinks;

static bool in_shard() {
    static int N = 0;
    return N++ % FLAGS_shards == FLAGS_shard;
}

static void push_src(ImplicitString tag, ImplicitString options, Src* s) {
    SkAutoTDelete<Src> src(s);
    if (in_shard() &&
        FLAGS_src.contains(tag.c_str()) &&
        !SkCommandLineFlags::ShouldSkip(FLAGS_match, src->name().c_str())) {
        TaggedSrc& s = gSrcs.push_back();
        s.reset(src.detach());
        s.tag = tag;
        s.options = options;
    }
}

static void push_codec_src(Path path, CodecSrc::Mode mode, CodecSrc::DstColorType dstColorType,
        float scale) {
    SkString folder;
    switch (mode) {
        case CodecSrc::kCodec_Mode:
            folder.append("codec");
            break;
        case CodecSrc::kCodecZeroInit_Mode:
            folder.append("codec_zero_init");
            break;
        case CodecSrc::kScanline_Mode:
            folder.append("scanline");
            break;
        case CodecSrc::kStripe_Mode:
            folder.append("stripe");
            break;
        case CodecSrc::kSubset_Mode:
            folder.append("codec_subset");
            break;
    }

    switch (dstColorType) {
        case CodecSrc::kGrayscale_Always_DstColorType:
            folder.append("_kGray8");
            break;
        case CodecSrc::kIndex8_Always_DstColorType:
            folder.append("_kIndex8");
            break;
        default:
            break;
    }

    if (1.0f != scale) {
        folder.appendf("_%.3f", scale);
    }

    CodecSrc* src = new CodecSrc(path, mode, dstColorType, scale);
    push_src("image", folder, src);
}

static void push_android_codec_src(Path path, AndroidCodecSrc::Mode mode,
        CodecSrc::DstColorType dstColorType, int sampleSize) {
    SkString folder;
    switch (mode) {
        case AndroidCodecSrc::kFullImage_Mode:
            folder.append("scaled_codec");
            break;
        case AndroidCodecSrc::kDivisor_Mode:
            folder.append("scaled_codec_divisor");
            break;
    }

    switch (dstColorType) {
        case CodecSrc::kGrayscale_Always_DstColorType:
            folder.append("_kGray8");
            break;
        case CodecSrc::kIndex8_Always_DstColorType:
            folder.append("_kIndex8");
            break;
        default:
            break;
    }

    if (1 != sampleSize) {
        folder.appendf("_%.3f", 1.0f / (float) sampleSize);
    }

    AndroidCodecSrc* src = new AndroidCodecSrc(path, mode, dstColorType, sampleSize);
    push_src("image", folder, src);
}

static void push_codec_srcs(Path path) {
    SkAutoTUnref<SkData> encoded(SkData::NewFromFileName(path.c_str()));
    if (!encoded) {
        SkDebugf("Couldn't read %s.", path.c_str());
        return;
    }
    SkAutoTDelete<SkCodec> codec(SkCodec::NewFromData(encoded));
    if (nullptr == codec.get()) {
        SkDebugf("Couldn't create codec for %s.", path.c_str());
        return;
    }

    // Native Scales
    // TODO (msarett): Implement scaling tests for SkImageDecoder in order to compare with these
    //                 tests.  SkImageDecoder supports downscales by integer factors.
    // SkJpegCodec natively supports scaling to: 0.125, 0.25, 0.375, 0.5, 0.625, 0.75, 0.875
    const float nativeScales[] = { 0.125f, 0.25f, 0.375f, 0.5f, 0.625f, 0.750f, 0.875f, 1.0f };

    const CodecSrc::Mode nativeModes[] = { CodecSrc::kCodec_Mode, CodecSrc::kCodecZeroInit_Mode,
            CodecSrc::kScanline_Mode, CodecSrc::kStripe_Mode, CodecSrc::kSubset_Mode };

    CodecSrc::DstColorType colorTypes[3];
    uint32_t numColorTypes;
    switch (codec->getInfo().colorType()) {
        case kGray_8_SkColorType:
            // FIXME: Is this a long term solution for testing wbmps decodes to kIndex8?
            // Further discussion on this topic is at https://bug.skia.org/3683 .
            // This causes us to try to convert grayscale jpegs to kIndex8.  We currently
            // fail non-fatally in this case.
            colorTypes[0] = CodecSrc::kGetFromCanvas_DstColorType;
            colorTypes[1] = CodecSrc::kGrayscale_Always_DstColorType;
            colorTypes[2] = CodecSrc::kIndex8_Always_DstColorType;
            numColorTypes = 3;
            break;
        case kIndex_8_SkColorType:
            colorTypes[0] = CodecSrc::kGetFromCanvas_DstColorType;
            colorTypes[1] = CodecSrc::kIndex8_Always_DstColorType;
            numColorTypes = 2;
            break;
        default:
            colorTypes[0] = CodecSrc::kGetFromCanvas_DstColorType;
            numColorTypes = 1;
            break;
    }

    for (float scale : nativeScales) {
        for (CodecSrc::Mode mode : nativeModes) {
            for (uint32_t i = 0; i < numColorTypes; i++) {
                push_codec_src(path, mode, colorTypes[i], scale);
            }
        }
    }

    // https://bug.skia.org/4428
    bool subset = false;
    // The following image types are supported by BitmapRegionDecoder,
    // so we will test full image decodes and subset decodes.
    static const char* const exts[] = {
        "jpg", "jpeg", "png", "webp",
        "JPG", "JPEG", "PNG", "WEBP",
    };
    for (const char* ext : exts) {
        if (path.endsWith(ext)) {
            subset = true;
            break;
        }
    }

    const int sampleSizes[] = { 1, 2, 3, 4, 5, 6, 7, 8 };

    for (int sampleSize : sampleSizes) {
        for (uint32_t i = 0; i < numColorTypes; i++) {
            push_android_codec_src(path, AndroidCodecSrc::kFullImage_Mode, colorTypes[i],
                    sampleSize);
            if (subset) {
                push_android_codec_src(path, AndroidCodecSrc::kDivisor_Mode, colorTypes[i],
                        sampleSize);
            }
        }
    }
}

static bool brd_color_type_supported(SkBitmapRegionDecoder::Strategy strategy,
        CodecSrc::DstColorType dstColorType) {
    switch (strategy) {
        case SkBitmapRegionDecoder::kCanvas_Strategy:
            if (CodecSrc::kGetFromCanvas_DstColorType == dstColorType) {
                return true;
            }
            return false;
        case SkBitmapRegionDecoder::kAndroidCodec_Strategy:
            switch (dstColorType) {
                case CodecSrc::kGetFromCanvas_DstColorType:
                case CodecSrc::kIndex8_Always_DstColorType:
                case CodecSrc::kGrayscale_Always_DstColorType:
                    return true;
                default:
                    return false;
            }
        default:
            SkASSERT(false);
            return false;
    }
}

static void push_brd_src(Path path, SkBitmapRegionDecoder::Strategy strategy,
        CodecSrc::DstColorType dstColorType, BRDSrc::Mode mode, uint32_t sampleSize) {
    SkString folder;
    switch (strategy) {
        case SkBitmapRegionDecoder::kCanvas_Strategy:
            folder.append("brd_canvas");
            break;
        case SkBitmapRegionDecoder::kAndroidCodec_Strategy:
            folder.append("brd_android_codec");
            break;
        default:
            SkASSERT(false);
            return;
    }

    switch (mode) {
        case BRDSrc::kFullImage_Mode:
            break;
        case BRDSrc::kDivisor_Mode:
            folder.append("_divisor");
            break;
        default:
            SkASSERT(false);
            return;
    }

    switch (dstColorType) {
        case CodecSrc::kGetFromCanvas_DstColorType:
            break;
        case CodecSrc::kIndex8_Always_DstColorType:
            folder.append("_kIndex");
            break;
        case CodecSrc::kGrayscale_Always_DstColorType:
            folder.append("_kGray");
            break;
        default:
            SkASSERT(false);
            return;
    }

    if (1 != sampleSize) {
        folder.appendf("_%.3f", 1.0f / (float) sampleSize);
    }

    BRDSrc* src = new BRDSrc(path, strategy, mode, dstColorType, sampleSize);
    push_src("image", folder, src);
}

static void push_brd_srcs(Path path) {

    const SkBitmapRegionDecoder::Strategy strategies[] = {
            SkBitmapRegionDecoder::kCanvas_Strategy,
            SkBitmapRegionDecoder::kAndroidCodec_Strategy,
    };

    // Test on a variety of sampleSizes, making sure to include:
    // - 2, 4, and 8, which are natively supported by jpeg
    // - multiples of 2 which are not divisible by 4 (analogous for 4)
    // - larger powers of two, since BRD clients generally use powers of 2
    // We will only produce output for the larger sizes on large images.
    const uint32_t sampleSizes[] = { 1, 2, 3, 4, 5, 6, 7, 8, 12, 16, 24, 32, 64 };

    // We will only test to one backend (8888), but we will test all of the
    // color types that we need to decode to on this backend.
    const CodecSrc::DstColorType dstColorTypes[] = {
            CodecSrc::kGetFromCanvas_DstColorType,
            CodecSrc::kIndex8_Always_DstColorType,
            CodecSrc::kGrayscale_Always_DstColorType,
    };

    const BRDSrc::Mode modes[] = {
            BRDSrc::kFullImage_Mode,
            BRDSrc::kDivisor_Mode,
    };

    for (SkBitmapRegionDecoder::Strategy strategy : strategies) {
        for (uint32_t sampleSize : sampleSizes) {
            for (CodecSrc::DstColorType dstColorType : dstColorTypes) {
                if (brd_color_type_supported(strategy, dstColorType)) {
                    for (BRDSrc::Mode mode : modes) {
                        push_brd_src(path, strategy, dstColorType, mode, sampleSize);
                    }
                }
            }
        }
    }
}

static bool brd_supported(const char* ext) {
    static const char* const exts[] = {
        "jpg", "jpeg", "png", "webp",
        "JPG", "JPEG", "PNG", "WEBP",
    };

    for (uint32_t i = 0; i < SK_ARRAY_COUNT(exts); i++) {
        if (0 == strcmp(exts[i], ext)) {
            return true;
        }
    }
    return false;
}

static void gather_srcs() {
    for (const skiagm::GMRegistry* r = skiagm::GMRegistry::Head(); r; r = r->next()) {
        push_src("gm", "", new GMSrc(r->factory()));
    }
    for (int i = 0; i < FLAGS_skps.count(); i++) {
        const char* path = FLAGS_skps[i];
        if (sk_isdir(path)) {
            SkOSFile::Iter it(path, "skp");
            for (SkString file; it.next(&file); ) {
                push_src("skp", "", new SKPSrc(SkOSPath::Join(path, file.c_str())));
            }
        } else {
            push_src("skp", "", new SKPSrc(path));
        }
    }
    static const char* const exts[] = {
        "bmp", "gif", "jpg", "jpeg", "png", "webp", "ktx", "astc", "wbmp", "ico",
        "BMP", "GIF", "JPG", "JPEG", "PNG", "WEBP", "KTX", "ASTC", "WBMP", "ICO",
    };
    for (int i = 0; i < FLAGS_images.count(); i++) {
        const char* flag = FLAGS_images[i];
        if (sk_isdir(flag)) {
            for (size_t j = 0; j < SK_ARRAY_COUNT(exts); j++) {
                SkOSFile::Iter it(flag, exts[j]);
                for (SkString file; it.next(&file); ) {
                    SkString path = SkOSPath::Join(flag, file.c_str());
                    push_src("image", "decode", new ImageSrc(path)); // Decode entire image
                    push_codec_srcs(path);
                    if (brd_supported(exts[j])) {
                        push_brd_srcs(path);
                    }
                }
            }
        } else if (sk_exists(flag)) {
            // assume that FLAGS_images[i] is a valid image if it is a file.
            push_src("image", "decode", new ImageSrc(flag)); // Decode entire image.
            push_codec_srcs(flag);
            push_brd_srcs(flag);
        }
    }
}

static void push_sink(const SkCommandLineConfig& config, Sink* s) {
    SkAutoTDelete<Sink> sink(s);

    // Try a simple Src as a canary.  If it fails, skip this sink.
    struct : public Src {
        Error draw(SkCanvas* c) const override {
            c->drawRect(SkRect::MakeWH(1,1), SkPaint());
            return "";
        }
        SkISize size() const override { return SkISize::Make(16, 16); }
        Name name() const override { return "justOneRect"; }
    } justOneRect;

    SkBitmap bitmap;
    SkDynamicMemoryWStream stream;
    SkString log;
    Error err = sink->draw(justOneRect, &bitmap, &stream, &log);
    if (err.isFatal()) {
        SkDebugf("Could not run %s: %s\n", config.getTag().c_str(), err.c_str());
        exit(1);
    }

    TaggedSink& ts = gSinks.push_back();
    ts.reset(sink.detach());
    ts.tag = config.getTag();
}

static bool gpu_supported() {
#if SK_SUPPORT_GPU
    return FLAGS_gpu;
#else
    return false;
#endif
}

static Sink* create_sink(const SkCommandLineConfig* config) {
#if SK_SUPPORT_GPU
    if (gpu_supported()) {
        if (const SkCommandLineConfigGpu* gpuConfig = config->asConfigGpu()) {
            GrContextFactory::GLContextType contextType = gpuConfig->getContextType();
            GrContextFactory::GLContextOptions contextOptions =
                    GrContextFactory::kNone_GLContextOptions;
            if (gpuConfig->getUseNVPR()) {
                contextOptions = static_cast<GrContextFactory::GLContextOptions>(
                    contextOptions | GrContextFactory::kEnableNVPR_GLContextOptions);
            }
            GrContextFactory testFactory;
            if (!testFactory.get(contextType, contextOptions)) {
                SkDebugf("WARNING: can not create GPU context for config '%s'. "
                         "GM tests will be skipped.\n", gpuConfig->getTag().c_str());
                return nullptr;
            }
            return new GPUSink(contextType, contextOptions, gpuConfig->getSamples(),
                               gpuConfig->getUseDIText(), FLAGS_gpu_threading);
        }
    }
#endif

#define SINK(t, sink, ...) if (config->getBackend().equals(t)) { return new sink(__VA_ARGS__); }

#ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK
    SINK("hwui",           HWUISink);
#endif

    if (FLAGS_cpu) {
        SINK("565",  RasterSink, kRGB_565_SkColorType);
        SINK("8888", RasterSink, kN32_SkColorType);
        SINK("pdf",  PDFSink, "Pdfium");
        SINK("pdf_poppler",  PDFSink, "Poppler");
        SINK("skp",  SKPSink);
        SINK("svg",  SVGSink);
        SINK("null", NullSink);
        SINK("xps",  XPSSink);
    }
#undef SINK
    return nullptr;
}

static Sink* create_via(const SkString& tag, Sink* wrapped) {
#define VIA(t, via, ...) if (tag.equals(t)) { return new via(__VA_ARGS__); }
    VIA("twice",     ViaTwice,             wrapped);
    VIA("serialize", ViaSerialization,     wrapped);
    VIA("pic",       ViaPicture,           wrapped);
    VIA("2ndpic",    ViaSecondPicture,     wrapped);
    VIA("sp",        ViaSingletonPictures, wrapped);
    VIA("tiles",     ViaTiles, 256, 256, nullptr,            wrapped);
    VIA("tiles_rt",  ViaTiles, 256, 256, new SkRTreeFactory, wrapped);
    VIA("remote",       ViaRemote, false, wrapped);
    VIA("remote_cache", ViaRemote, true,  wrapped);

    if (FLAGS_matrix.count() == 4) {
        SkMatrix m;
        m.reset();
        m.setScaleX((SkScalar)atof(FLAGS_matrix[0]));
        m.setSkewX ((SkScalar)atof(FLAGS_matrix[1]));
        m.setSkewY ((SkScalar)atof(FLAGS_matrix[2]));
        m.setScaleY((SkScalar)atof(FLAGS_matrix[3]));
        VIA("matrix",  ViaMatrix,  m, wrapped);
        VIA("upright", ViaUpright, m, wrapped);
    }

#ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK
    VIA("androidsdk", ViaAndroidSDK, wrapped);
#endif

#undef VIA
    return nullptr;
}

static void gather_sinks() {
    SkCommandLineConfigArray configs;
    ParseConfigs(FLAGS_config, &configs);
    for (int i = 0; i < configs.count(); i++) {
        const SkCommandLineConfig& config = *configs[i];
        Sink* sink = create_sink(&config);
        if (sink == nullptr) {
            SkDebugf("Skipping config %s: Don't understand '%s'.\n", config.getTag().c_str(),
                     config.getTag().c_str());
            continue;
        }

        const SkTArray<SkString>& parts = config.getViaParts();
        for (int j = parts.count(); j-- > 0;) {
            const SkString& part = parts[j];
            Sink* next = create_via(part, sink);
            if (next == nullptr) {
                SkDebugf("Skipping config %s: Don't understand '%s'.\n", config.getTag().c_str(),
                         part.c_str());
                delete sink;
                sink = nullptr;
                break;
            }
            sink = next;
        }
        if (sink) {
            push_sink(config, sink);
        }
    }
}

static bool dump_png(SkBitmap bitmap, const char* path, const char* md5) {
    const int w = bitmap.width(),
              h = bitmap.height();

    // First get the bitmap into N32 color format.  The next step will work only there.
    if (bitmap.colorType() != kN32_SkColorType) {
        SkBitmap n32;
        if (!bitmap.copyTo(&n32, kN32_SkColorType)) {
            return false;
        }
        bitmap = n32;
    }

    // Convert our N32 bitmap into unpremul RGBA for libpng.
    SkAutoTMalloc<uint32_t> rgba(w*h);
    if (!bitmap.readPixels(SkImageInfo::Make(w,h, kRGBA_8888_SkColorType, kUnpremul_SkAlphaType),
                           rgba, 4*w, 0,0)) {
        return false;
    }

    // We don't need bitmap anymore.  Might as well drop our ref.
    bitmap.reset();

    FILE* f = fopen(path, "wb");
    if (!f) { return false; }

    png_structp png = png_create_write_struct(PNG_LIBPNG_VER_STRING, nullptr, nullptr, nullptr);
    if (!png) {
        fclose(f);
        return false;
    }

    png_infop info = png_create_info_struct(png);
    if (!info) {
        png_destroy_write_struct(&png, &info);
        fclose(f);
        return false;
    }

    SkString description;
    description.append("Key: ");
    for (int i = 0; i < FLAGS_key.count(); i++) {
        description.appendf("%s ", FLAGS_key[i]);
    }
    description.append("Properties: ");
    for (int i = 0; i < FLAGS_properties.count(); i++) {
        description.appendf("%s ", FLAGS_properties[i]);
    }
    description.appendf("MD5: %s", md5);

    png_text text[2];
    text[0].key = (png_charp)"Author";
    text[0].text = (png_charp)"DM dump_png()";
    text[0].compression = PNG_TEXT_COMPRESSION_NONE;
    text[1].key = (png_charp)"Description";
    text[1].text = (png_charp)description.c_str();
    text[1].compression = PNG_TEXT_COMPRESSION_NONE;
    png_set_text(png, info, text, 2);

    png_init_io(png, f);
    png_set_IHDR(png, info, (png_uint_32)w, (png_uint_32)h, 8,
                 PNG_COLOR_TYPE_RGB_ALPHA, PNG_INTERLACE_NONE,
                 PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);
    png_write_info(png, info);
    for (int j = 0; j < h; j++) {
        png_bytep row = (png_bytep)(rgba.get() + w*j);
        png_write_rows(png, &row, 1);
    }
    png_write_end(png, info);

    png_destroy_write_struct(&png, &info);
    fclose(f);
    return true;
}

static bool match(const char* needle, const char* haystack) {
    return 0 == strcmp("_", needle) || nullptr != strstr(haystack, needle);
}

static ImplicitString is_blacklisted(const char* sink, const char* src,
                                     const char* srcOptions, const char* name) {
    for (int i = 0; i < FLAGS_blacklist.count() - 3; i += 4) {
        if (match(FLAGS_blacklist[i+0], sink) &&
            match(FLAGS_blacklist[i+1], src) &&
            match(FLAGS_blacklist[i+2], srcOptions) &&
            match(FLAGS_blacklist[i+3], name)) {
            return SkStringPrintf("%s %s %s %s",
                                  FLAGS_blacklist[i+0], FLAGS_blacklist[i+1],
                                  FLAGS_blacklist[i+2], FLAGS_blacklist[i+3]);
        }
    }
    return "";
}

// Even when a Task Sink reports to be non-threadsafe (e.g. GPU), we know things like
// .png encoding are definitely thread safe.  This lets us offload that work to CPU threads.
static SkTaskGroup gDefinitelyThreadSafeWork;

// The finest-grained unit of work we can run: draw a single Src into a single Sink,
// report any errors, and perhaps write out the output: a .png of the bitmap, or a raw stream.
struct Task {
    Task(const TaggedSrc& src, const TaggedSink& sink) : src(src), sink(sink) {}
    const TaggedSrc&  src;
    const TaggedSink& sink;

    static void Run(Task* task) {
        SkString name = task->src->name();

        // We'll skip drawing this Src/Sink pair if:
        //   - the Src vetoes the Sink;
        //   - this Src / Sink combination is on the blacklist;
        //   - it's a dry run.
        SkString note(task->src->veto(task->sink->flags()) ? " (veto)" : "");
        SkString whyBlacklisted = is_blacklisted(task->sink.tag.c_str(), task->src.tag.c_str(),
                                                 task->src.options.c_str(), name.c_str());
        if (!whyBlacklisted.isEmpty()) {
            note.appendf(" (--blacklist %s)", whyBlacklisted.c_str());
        }

        SkString log;
        auto timerStart = now_ms();
        if (!FLAGS_dryRun && note.isEmpty()) {
            SkBitmap bitmap;
            SkDynamicMemoryWStream stream;
            if (FLAGS_pre_log) {
                SkDebugf("\nRunning %s->%s", name.c_str(), task->sink.tag.c_str());
            }
            start(task->sink.tag.c_str(), task->src.tag, task->src.options, name.c_str());
            Error err = task->sink->draw(*task->src, &bitmap, &stream, &log);
            if (!err.isEmpty()) {
                if (err.isFatal()) {
                    fail(SkStringPrintf("%s %s %s %s: %s",
                                        task->sink.tag.c_str(),
                                        task->src.tag.c_str(),
                                        task->src.options.c_str(),
                                        name.c_str(),
                                        err.c_str()));
                } else {
                    note.appendf(" (skipped: %s)", err.c_str());
                    auto elapsed = now_ms() - timerStart;
                    done(elapsed, task->sink.tag.c_str(), task->src.tag, task->src.options,
                         name, note, log);
                    return;
                }
            }

            // We're likely switching threads here, so we must capture by value, [=] or [foo,bar].
            SkStreamAsset* data = stream.detachAsStream();
            gDefinitelyThreadSafeWork.add([task,name,bitmap,data]{
                SkAutoTDelete<SkStreamAsset> ownedData(data);

                // Why doesn't the copy constructor do this when we have pre-locked pixels?
                bitmap.lockPixels();

                SkString md5;
                if (!FLAGS_writePath.isEmpty() || !FLAGS_readPath.isEmpty()) {
                    SkMD5 hash;
                    if (data->getLength()) {
                        hash.writeStream(data, data->getLength());
                        data->rewind();
                    } else {
                        // If we're BGRA (Linux, Windows), swizzle over to RGBA (Mac, Android).
                        // This helps eliminate multiple 0-pixel-diff hashes on gold.skia.org.
                        // (Android's general slow speed breaks the tie arbitrarily in RGBA's favor.)
                        // We might consider promoting 565 to RGBA too.
                        if (bitmap.colorType() == kBGRA_8888_SkColorType) {
                            SkBitmap swizzle;
                            SkAssertResult(bitmap.copyTo(&swizzle, kRGBA_8888_SkColorType));
                            hash.write(swizzle.getPixels(), swizzle.getSize());
                        } else {
                            hash.write(bitmap.getPixels(), bitmap.getSize());
                        }
                    }
                    SkMD5::Digest digest;
                    hash.finish(digest);
                    for (int i = 0; i < 16; i++) {
                        md5.appendf("%02x", digest.data[i]);
                    }
                }

                if (!FLAGS_readPath.isEmpty() &&
                    !gGold.contains(Gold(task->sink.tag.c_str(), task->src.tag.c_str(),
                                         task->src.options.c_str(), name, md5))) {
                    fail(SkStringPrintf("%s not found for %s %s %s %s in %s",
                                        md5.c_str(),
                                        task->sink.tag.c_str(),
                                        task->src.tag.c_str(),
                                        task->src.options.c_str(),
                                        name.c_str(),
                                        FLAGS_readPath[0]));
                }

                if (!FLAGS_writePath.isEmpty()) {
                    const char* ext = task->sink->fileExtension();
                    if (data->getLength()) {
                        WriteToDisk(*task, md5, ext, data, data->getLength(), nullptr);
                        SkASSERT(bitmap.drawsNothing());
                    } else if (!bitmap.drawsNothing()) {
                        WriteToDisk(*task, md5, ext, nullptr, 0, &bitmap);
                    }
                }
            });
        }
        auto elapsed = now_ms() - timerStart;
        done(elapsed, task->sink.tag.c_str(), task->src.tag.c_str(), task->src.options.c_str(),
             name, note, log);
    }

    static void WriteToDisk(const Task& task,
                            SkString md5,
                            const char* ext,
                            SkStream* data, size_t len,
                            const SkBitmap* bitmap) {
        JsonWriter::BitmapResult result;
        result.name          = task.src->name();
        result.config        = task.sink.tag.c_str();
        result.sourceType    = task.src.tag;
        result.sourceOptions = task.src.options;
        result.ext           = ext;
        result.md5           = md5;
        JsonWriter::AddBitmapResult(result);

        // If an MD5 is uninteresting, we want it noted in the JSON file,
        // but don't want to dump it out as a .png (or whatever ext is).
        if (gUninterestingHashes.contains(md5)) {
            return;
        }

        const char* dir = FLAGS_writePath[0];
        if (0 == strcmp(dir, "@")) {  // Needed for iOS.
            dir = FLAGS_resourcePath[0];
        }
        sk_mkdir(dir);

        SkString path;
        if (FLAGS_nameByHash) {
            path = SkOSPath::Join(dir, result.md5.c_str());
            path.append(".");
            path.append(ext);
            if (sk_exists(path.c_str())) {
                return;  // Content-addressed.  If it exists already, we're done.
            }
        } else {
            path = SkOSPath::Join(dir, task.sink.tag.c_str());
            sk_mkdir(path.c_str());
            path = SkOSPath::Join(path.c_str(), task.src.tag.c_str());
            sk_mkdir(path.c_str());
            if (strcmp(task.src.options.c_str(), "") != 0) {
              path = SkOSPath::Join(path.c_str(), task.src.options.c_str());
              sk_mkdir(path.c_str());
            }
            path = SkOSPath::Join(path.c_str(), task.src->name().c_str());
            path.append(".");
            path.append(ext);
        }

        if (bitmap) {
            if (!dump_png(*bitmap, path.c_str(), result.md5.c_str())) {
                fail(SkStringPrintf("Can't encode PNG to %s.\n", path.c_str()));
                return;
            }
        } else {
            SkFILEWStream file(path.c_str());
            if (!file.isValid()) {
                fail(SkStringPrintf("Can't open %s for writing.\n", path.c_str()));
                return;
            }
            if (!file.writeStream(data, len)) {
                fail(SkStringPrintf("Can't write to %s.\n", path.c_str()));
                return;
            }
        }
    }
};

// Run all tasks in the same enclave serially on the same thread.
// They can't possibly run concurrently with each other.
static void run_enclave(SkTArray<Task>* tasks) {
    for (int i = 0; i < tasks->count(); i++) {
        Task::Run(tasks->begin() + i);
    }
}

/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/

// Unit tests don't fit so well into the Src/Sink model, so we give them special treatment.

static SkTDArray<skiatest::Test> gThreadedTests, gGPUTests;

static void gather_tests() {
    if (!FLAGS_src.contains("tests")) {
        return;
    }
    for (const skiatest::TestRegistry* r = skiatest::TestRegistry::Head(); r; r = r->next()) {
        if (!in_shard()) {
            continue;
        }
        // Despite its name, factory() is returning a reference to
        // link-time static const POD data.
        const skiatest::Test& test = r->factory();
        if (SkCommandLineFlags::ShouldSkip(FLAGS_match, test.name)) {
            continue;
        }
        if (test.needsGpu && gpu_supported()) {
            (FLAGS_gpu_threading ? gThreadedTests : gGPUTests).push(test);
        } else if (!test.needsGpu && FLAGS_cpu) {
            gThreadedTests.push(test);
        }
    }
}

static void run_test(skiatest::Test* test) {
    struct : public skiatest::Reporter {
        void reportFailed(const skiatest::Failure& failure) override {
            fail(failure.toString());
            JsonWriter::AddTestFailure(failure);
        }
        bool allowExtendedTest() const override {
            return FLAGS_pathOpsExtended;
        }
        bool verbose() const override { return FLAGS_veryVerbose; }
    } reporter;

    SkString note;
    SkString whyBlacklisted = is_blacklisted("_", "tests", "_", test->name);
    if (!whyBlacklisted.isEmpty()) {
        note.appendf(" (--blacklist %s)", whyBlacklisted.c_str());
    }

    auto timerStart = now_ms();
    if (!FLAGS_dryRun && whyBlacklisted.isEmpty()) {
        start("unit", "test", "", test->name);
        GrContextFactory factory;
        if (FLAGS_pre_log) {
            SkDebugf("\nRunning test %s", test->name);
        }
        test->proc(&reporter, &factory);
    }
    done(now_ms()-timerStart, "unit", "test", "", test->name, note, "");
}

/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/

// If we're isolating all GPU-bound work to one thread (the default), this function runs all that.
static void run_enclave_and_gpu_tests(SkTArray<Task>* tasks) {
    run_enclave(tasks);
    for (int i = 0; i < gGPUTests.count(); i++) {
        run_test(&gGPUTests[i]);
    }
}

// Some runs (mostly, Valgrind) are so slow that the bot framework thinks we've hung.
// This prints something every once in a while so that it knows we're still working.
static void start_keepalive() {
    struct Loop {
        static void forever(void*) {
            for (;;) {
                static const int kSec = 300;
            #if defined(SK_BUILD_FOR_WIN)
                Sleep(kSec * 1000);
            #else
                sleep(kSec);
            #endif
                SkString running;
                {
                    SkAutoMutexAcquire lock(gRunningAndTallyMutex);
                    for (int i = 0; i < gRunning.count(); i++) {
                        running.appendf("\n\t%s", gRunning[i].c_str());
                    }
                }
                SkDebugf("\nCurrently running:%s\n", running.c_str());
            }
        }
    };
    static SkThread* intentionallyLeaked = new SkThread(Loop::forever);
    intentionallyLeaked->start();
}

#define PORTABLE_FONT_PREFIX "Toy Liberation "

static SkTypeface* create_from_name(const char familyName[], SkTypeface::Style style) {
    if (familyName && strlen(familyName) > sizeof(PORTABLE_FONT_PREFIX)
            && !strncmp(familyName, PORTABLE_FONT_PREFIX, sizeof(PORTABLE_FONT_PREFIX) - 1)) {
        return sk_tool_utils::create_portable_typeface(familyName, style);
    }
    return nullptr;
}

#undef PORTABLE_FONT_PREFIX

extern SkTypeface* (*gCreateTypefaceDelegate)(const char [], SkTypeface::Style );

int dm_main();
int dm_main() {
    SetupCrashHandler();
    SkAutoGraphics ag;
    SkTaskGroup::Enabler enabled(FLAGS_threads);
    gCreateTypefaceDelegate = &create_from_name;

    start_keepalive();

    gather_gold();
    gather_uninteresting_hashes();

    gather_srcs();
    gather_sinks();
    gather_tests();

    gPending = gSrcs.count() * gSinks.count() + gThreadedTests.count() + gGPUTests.count();
    SkDebugf("%d srcs * %d sinks + %d tests == %d tasks\n",
             gSrcs.count(), gSinks.count(), gThreadedTests.count() + gGPUTests.count(), gPending);

    // We try to exploit as much parallelism as is safe.  Most Src/Sink pairs run on any thread,
    // but Sinks that identify as part of a particular enclave run serially on a single thread.
    // CPU tests run on any thread.  GPU tests depend on --gpu_threading.
    SkTArray<Task> enclaves[kNumEnclaves];
    for (int j = 0; j < gSinks.count(); j++) {
        SkTArray<Task>& tasks = enclaves[gSinks[j]->enclave()];
        for (int i = 0; i < gSrcs.count(); i++) {
            tasks.push_back(Task(gSrcs[i], gSinks[j]));
        }
    }

    SkTaskGroup tg;
    tg.batch(gThreadedTests.count(), [](int i){ run_test(&gThreadedTests[i]); });
    for (int i = 0; i < kNumEnclaves; i++) {
        SkTArray<Task>* currentEnclave = &enclaves[i];
        switch(i) {
            case kAnyThread_Enclave:
                tg.batch(currentEnclave->count(),
                         [currentEnclave](int j) { Task::Run(&(*currentEnclave)[j]); });
                break;
            case kGPU_Enclave:
                tg.add([currentEnclave](){ run_enclave_and_gpu_tests(currentEnclave); });
                break;
            default:
                tg.add([currentEnclave](){ run_enclave(currentEnclave); });
                break;
        }
    }
    tg.wait();
    gDefinitelyThreadSafeWork.wait();

    // At this point we're back in single-threaded land.
    sk_tool_utils::release_portable_typefaces();

    if (FLAGS_verbose && gNoteTally.count() > 0) {
        SkDebugf("\nNote tally:\n");
        gNoteTally.foreach([](const SkString& note, int* tally) {
            SkDebugf("%dx\t%s\n", *tally, note.c_str());
        });
    }

    SkDebugf("\n");
    if (gFailures.count() > 0) {
        SkDebugf("Failures:\n");
        for (int i = 0; i < gFailures.count(); i++) {
            SkDebugf("\t%s\n", gFailures[i].c_str());
        }
        SkDebugf("%d failures\n", gFailures.count());
        return 1;
    }
    if (gPending > 0) {
        SkDebugf("Hrm, we didn't seem to run everything we intended to!  Please file a bug.\n");
        return 1;
    }
    #ifdef SK_PDF_IMAGE_STATS
    SkPDFImageDumpStats();
    #endif  // SK_PDF_IMAGE_STATS
    return 0;
}

// TODO: currently many GPU tests are declared outside SK_SUPPORT_GPU guards.
// Thus we export the empty RunWithGPUTestContexts when SK_SUPPORT_GPU=0.
namespace skiatest {
namespace {
typedef void(*TestWithGrContext)(skiatest::Reporter*, GrContext*);
typedef void(*TestWithGrContextAndGLContext)(skiatest::Reporter*, GrContext*, SkGLContext*);
#if SK_SUPPORT_GPU
template<typename T>
void call_test(T test, skiatest::Reporter* reporter, const GrContextFactory::ContextInfo& context);
template<>
void call_test(TestWithGrContext test, skiatest::Reporter* reporter,
               const GrContextFactory::ContextInfo& context) {
    test(reporter, context.fGrContext);
}
template<>
void call_test(TestWithGrContextAndGLContext test, skiatest::Reporter* reporter,
               const GrContextFactory::ContextInfo& context) {
    test(reporter, context.fGrContext, context.fGLContext);
}
#endif
} // namespace

template<typename T>
void RunWithGPUTestContexts(T test, GPUTestContexts testContexts, Reporter* reporter,
                            GrContextFactory* factory) {
#if SK_SUPPORT_GPU
    // Iterate over context types, except use "native" instead of explicitly trying OpenGL and
    // OpenGL ES. Do not use GLES on desktop, since tests do not account for not fixing
    // http://skbug.com/2809
    GrContextFactory::GLContextType contextTypes[] = {
        GrContextFactory::kNative_GLContextType,
#if SK_ANGLE
#ifdef SK_BUILD_FOR_WIN
        GrContextFactory::kANGLE_GLContextType,
#endif
        GrContextFactory::kANGLE_GL_GLContextType,
#endif
#if SK_COMMAND_BUFFER
        GrContextFactory::kCommandBuffer_GLContextType,
#endif
#if SK_MESA
        GrContextFactory::kMESA_GLContextType,
#endif
        GrContextFactory::kNull_GLContextType,
        GrContextFactory::kDebug_GLContextType,
    };
    static_assert(SK_ARRAY_COUNT(contextTypes) == GrContextFactory::kGLContextTypeCnt - 2,
                  "Skipping unexpected GLContextType for GPU tests");

    for (auto& contextType : contextTypes) {
        int contextSelector = kNone_GPUTestContexts;
        if (GrContextFactory::IsRenderingGLContext(contextType)) {
            contextSelector |= kAllRendering_GPUTestContexts;
        } else if (contextType == GrContextFactory::kNative_GLContextType) {
            contextSelector |= kNative_GPUTestContexts;
        } else if (contextType == GrContextFactory::kNull_GLContextType) {
            contextSelector |= kNull_GPUTestContexts;
        } else if (contextType == GrContextFactory::kDebug_GLContextType) {
            contextSelector |= kDebug_GPUTestContexts;
        }
        if ((testContexts & contextSelector) == 0) {
            continue;
        }
        GrContextFactory::ContextInfo context = factory->getContextInfo(contextType);
        if (context.fGrContext) {
            call_test(test, reporter, context);
        }
        context = factory->getContextInfo(contextType,
                                          GrContextFactory::kEnableNVPR_GLContextOptions);
        if (context.fGrContext) {
            call_test(test, reporter, context);
        }
    }
#endif
}

template
void RunWithGPUTestContexts<TestWithGrContext>(TestWithGrContext test,
                                               GPUTestContexts testContexts,
                                               Reporter* reporter,
                                               GrContextFactory* factory);
template
void RunWithGPUTestContexts<TestWithGrContextAndGLContext>(TestWithGrContextAndGLContext test,
                                                           GPUTestContexts testContexts,
                                                           Reporter* reporter,
                                                           GrContextFactory* factory);
} // namespace skiatest

#if !defined(SK_BUILD_FOR_IOS)
int main(int argc, char** argv) {
    SkCommandLineFlags::Parse(argc, argv);
    return dm_main();
}
#endif