Fix rewinding bug in SkJpegCodec

src/codec/SkJpegCodec.cpp

 /*
  * Copyright 2015 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 "SkMSAN.h"
 #include "SkJpegCodec.h"
@@ skipping 245 matching lines @@
     }
     return nullptr;
 }
 
 SkJpegCodec::SkJpegCodec(int width, int height, const SkEncodedInfo& info, SkStream* stream,
         JpegDecoderMgr* decoderMgr, sk_sp<SkColorSpace> colorSpace, Origin origin,
         sk_sp<SkData> iccData)
     : INHERITED(width, height, info, stream, std::move(colorSpace), origin)
     , fDecoderMgr(decoderMgr)
     , fReadyState(decoderMgr->dinfo()->global_state)
+    , fSrcRow(nullptr)
     , fSwizzlerSubset(SkIRect::MakeEmpty())
     , fICCData(std::move(iccData))
 {}
 
 /*
  * Return the row bytes of a particular image type and width
  */
 static size_t get_row_bytes(const j_decompress_ptr dinfo) {
 #ifdef TURBO_HAS_565
     const size_t colorBytes = (dinfo->out_color_space == JCS_RGB565) ? 2 :
@@ skipping 56 matching lines @@
     return SkISize::Make(dinfo.output_width, dinfo.output_height);
 }
 
 bool SkJpegCodec::onRewind() {
     JpegDecoderMgr* decoderMgr = nullptr;
     if (!ReadHeader(this->stream(), nullptr, &decoderMgr)) {
         return fDecoderMgr->returnFalse("could not rewind");
     }
     SkASSERT(nullptr != decoderMgr);
     fDecoderMgr.reset(decoderMgr);
+
+    fSwizzler.reset(nullptr);
+    fSrcRow = nullptr;
+    fStorage.reset();
+
     return true;
 }
 
 /*
  * Checks if the conversion between the input image and the requested output
  * image has been implemented
  * Sets the output color space
  */
 bool SkJpegCodec::setOutputColorSpace(const SkImageInfo& dst) {
     if (kUnknown_SkAlphaType == dst.alphaType()) {
@@ skipping 229 matching lines @@
     if (setjmp(fDecoderMgr->getJmpBuf())) {
         SkCodecPrintf("setjmp: Error from libjpeg\n");
         return kInvalidInput;
     }
 
     // Check if we can decode to the requested destination and set the output color space
     if (!this->setOutputColorSpace(dstInfo)) {
         return kInvalidConversion;
     }
 
-    // Remove objects used for sampling.
-    fSwizzler.reset(nullptr);
-    fSrcRow = nullptr;
-    fStorage.reset();
-
     // Now, given valid output dimensions, we can start the decompress
     if (!jpeg_start_decompress(fDecoderMgr->dinfo())) {
         SkCodecPrintf("start decompress failed\n");
         return kInvalidInput;
     }
 
     if (options.fSubset) {
         fSwizzlerSubset = *options.fSubset;
     }
 
@@ skipping 301 matching lines @@
 
         JDIMENSION linesRead = jpeg_read_raw_data(dinfo, yuv, numRowsPerBlock);
         if (linesRead < remainingRows) {
             // FIXME: Handle incomplete YUV decodes without signalling an error.
             return kInvalidInput;
         }
     }
 
     return kSuccess;
 }