Revert of Make SkPngCodec decode progressively.

tests/CodecPartial.cpp

-/*
- * Copyright 2016 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#include "SkCodec.h"
-#include "SkData.h"
-#include "SkImageInfo.h"
-#include "SkRWBuffer.h"
-#include "SkString.h"
-
-#include "Resources.h"
-#include "Test.h"
-
-static sk_sp<SkData> make_from_resource(const char* name) {
-    SkString fullPath = GetResourcePath(name);
-    return SkData::MakeFromFileName(fullPath.c_str());
-}
-
-static SkImageInfo standardize_info(SkCodec* codec) {
-    SkImageInfo defaultInfo = codec->getInfo();
-    return SkImageInfo::MakeN32Premul(defaultInfo.width(), defaultInfo.height());
-}
-
-static bool create_truth(sk_sp<SkData> data, SkBitmap* dst) {
-    SkAutoTDelete<SkCodec> codec(SkCodec::NewFromData(data.get()));
-    if (!codec) {
-        return false;
-    }
-
-    const SkImageInfo info = standardize_info(codec);
-    dst->allocPixels(info);
-    return SkCodec::kSuccess == codec->getPixels(info, dst->getPixels(), dst->rowBytes());
-}
-
-/*
- *  Represents a stream without all of its data.
- */
-class HaltingStream : public SkStream {
-public:
-    HaltingStream(sk_sp<SkData> data)
-        : fTotalSize(data->size())
-        , fLimit(fTotalSize / 2)
-        , fStream(std::move(data))
-    {}
-
-    void addNewData() {
-        // Arbitrary size, but deliberately different from
-        // the buffer size used by SkPngCodec.
-        fLimit = SkTMin(fTotalSize, fLimit + 1000);
-    }
-
-    size_t read(void* buffer, size_t size) override {
-        if (fStream.getPosition() + size > fLimit) {
-            size = fLimit - fStream.getPosition();
-        }
-
-        return fStream.read(buffer, size);
-    }
-
-    bool isAtEnd() const override {
-        return fStream.isAtEnd();
-    }
-
-    bool hasPosition() const override { return true; }
-    size_t getPosition() const override { return fStream.getPosition(); }
-    bool rewind() override { return fStream.rewind(); }
-
-private:
-    const size_t    fTotalSize;
-    size_t          fLimit;
-    SkMemoryStream  fStream;
-};
-
-static void test_partial(skiatest::Reporter* r, const char* name) {
-    sk_sp<SkData> file = make_from_resource(name);
-    if (!file) {
-        SkDebugf("missing resource %s\n", name);
-        return;
-    }
-
-    SkBitmap truth;
-    if (!create_truth(file, &truth)) {
-        ERRORF(r, "Failed to decode %s\n", name);
-        return;
-    }
-
-    const size_t fileSize = file->size();
-
-    // Now decode part of the file
-    HaltingStream* stream = new HaltingStream(file);
-
-    // Note that we cheat and hold on to a pointer to stream, though it is owned by
-    // partialCodec.
-    SkAutoTDelete<SkCodec> partialCodec(SkCodec::NewFromStream(stream));
-    if (!partialCodec) {
-        // Technically, this could be a small file where half the file is not
-        // enough.
-        ERRORF(r, "Failed to create codec for %s", name);
-        return;
-    }
-
-    const SkImageInfo info = standardize_info(partialCodec);
-    SkASSERT(info == truth.info());
-    SkBitmap incremental;
-    incremental.allocPixels(info);
-
-    const SkCodec::Result startResult = partialCodec->startIncrementalDecode(info,
-            incremental.getPixels(), incremental.rowBytes());
-    if (startResult != SkCodec::kSuccess) {
-        ERRORF(r, "Failed to start incremental decode\n");
-        return;
-    }
-
-    while (true) {
-        const SkCodec::Result result = partialCodec->incrementalDecode();
-
-        if (stream->getPosition() == fileSize) {
-            REPORTER_ASSERT(r, result == SkCodec::kSuccess);
-            break;
-        }
-
-        SkASSERT(stream->getPosition() < fileSize);
-
-        REPORTER_ASSERT(r, result == SkCodec::kIncompleteInput);
-
-        // Append an arbitrary amount of data.
-        stream->addNewData();
-    }
-
-    // compare to original
-    for (int i = 0; i < info.height(); i++) {
-        REPORTER_ASSERT(r, !memcmp(truth.getAddr(0, 0), incremental.getAddr(0, 0),
-                                   info.minRowBytes()));
-    }
-}
-
-DEF_TEST(Codec_partial, r) {
-    test_partial(r, "plane.png");
-    test_partial(r, "plane_interlaced.png");
-    test_partial(r, "yellow_rose.png");
-    test_partial(r, "index8.png");
-    test_partial(r, "color_wheel.png");
-    test_partial(r, "mandrill_256.png");
-    test_partial(r, "mandrill_32.png");
-    test_partial(r, "arrow.png");
-    test_partial(r, "randPixels.png");
-    test_partial(r, "baby_tux.png");
-}