Пример #1
0
void
nsJPEGDecoder::WriteInternal(const char* aBuffer, uint32_t aCount,
                             DecodeStrategy)
{
  mSegment = (const JOCTET*)aBuffer;
  mSegmentLen = aCount;

  NS_ABORT_IF_FALSE(!HasError(), "Shouldn't call WriteInternal after error!");

  // Return here if there is a fatal error within libjpeg.
  nsresult error_code;
  // This cast to nsresult makes sense because setjmp() returns whatever we
  // passed to longjmp(), which was actually an nsresult.
  if ((error_code = (nsresult)setjmp(mErr.setjmp_buffer)) != NS_OK) {
    if (error_code == NS_ERROR_FAILURE) {
      PostDataError();
      // Error due to corrupt stream - return NS_OK and consume silently
      // so that ImageLib doesn't throw away a partial image load
      mState = JPEG_SINK_NON_JPEG_TRAILER;
      PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
             ("} (setjmp returned NS_ERROR_FAILURE)"));
      return;
    } else {
      // Error due to reasons external to the stream (probably out of
      // memory) - let ImageLib attempt to clean up, even though
      // mozilla is seconds away from falling flat on its face.
      PostDecoderError(error_code);
      mState = JPEG_ERROR;
      PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
             ("} (setjmp returned an error)"));
      return;
    }
  }

  PR_LOG(GetJPEGLog(), PR_LOG_DEBUG,
         ("[this=%p] nsJPEGDecoder::Write -- processing JPEG data\n", this));

  switch (mState) {
    case JPEG_HEADER: {
      LOG_SCOPE(GetJPEGLog(), "nsJPEGDecoder::Write -- entering JPEG_HEADER"
                " case");

      // Step 3: read file parameters with jpeg_read_header()
      if (jpeg_read_header(&mInfo, TRUE) == JPEG_SUSPENDED) {
        PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
               ("} (JPEG_SUSPENDED)"));
        return; // I/O suspension
      }

      int sampleSize = mImage.GetRequestedSampleSize();
      if (sampleSize > 0) {
        mInfo.scale_num = 1;
        mInfo.scale_denom = sampleSize;
      }

      // Used to set up image size so arrays can be allocated
      jpeg_calc_output_dimensions(&mInfo);

      // Post our size to the superclass
      PostSize(mInfo.output_width, mInfo.output_height,
               ReadOrientationFromEXIF());
      if (HasError()) {
        // Setting the size led to an error.
        mState = JPEG_ERROR;
        return;
      }

      // If we're doing a size decode, we're done.
      if (IsSizeDecode()) {
        return;
      }

      // We're doing a full decode.
      if (mCMSMode != eCMSMode_Off &&
          (mInProfile = GetICCProfile(mInfo)) != nullptr) {
        uint32_t profileSpace = qcms_profile_get_color_space(mInProfile);
        bool mismatch = false;

#ifdef DEBUG_tor
      fprintf(stderr, "JPEG profileSpace: 0x%08X\n", profileSpace);
#endif
      switch (mInfo.jpeg_color_space) {
        case JCS_GRAYSCALE:
          if (profileSpace == icSigRgbData) {
            mInfo.out_color_space = JCS_RGB;
          } else if (profileSpace != icSigGrayData) {
            mismatch = true;
          }
          break;
        case JCS_RGB:
          if (profileSpace != icSigRgbData) {
            mismatch =  true;
          }
          break;
        case JCS_YCbCr:
          if (profileSpace == icSigRgbData) {
            mInfo.out_color_space = JCS_RGB;
          } else {
            // qcms doesn't support ycbcr
            mismatch = true;
          }
          break;
        case JCS_CMYK:
        case JCS_YCCK:
            // qcms doesn't support cmyk
            mismatch = true;
          break;
        default:
          mState = JPEG_ERROR;
          PostDataError();
          PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
                 ("} (unknown colorpsace (1))"));
          return;
      }

      if (!mismatch) {
        qcms_data_type type;
        switch (mInfo.out_color_space) {
          case JCS_GRAYSCALE:
            type = QCMS_DATA_GRAY_8;
            break;
          case JCS_RGB:
            type = QCMS_DATA_RGB_8;
            break;
          default:
            mState = JPEG_ERROR;
            PostDataError();
            PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
                   ("} (unknown colorpsace (2))"));
            return;
        }
#if 0
        // We don't currently support CMYK profiles. The following
        // code dealt with lcms types. Add something like this
        // back when we gain support for CMYK.

        // Adobe Photoshop writes YCCK/CMYK files with inverted data
        if (mInfo.out_color_space == JCS_CMYK) {
          type |= FLAVOR_SH(mInfo.saw_Adobe_marker ? 1 : 0);
        }
#endif

        if (gfxPlatform::GetCMSOutputProfile()) {

          // Calculate rendering intent.
          int intent = gfxPlatform::GetRenderingIntent();
          if (intent == -1) {
            intent = qcms_profile_get_rendering_intent(mInProfile);
          }

          // Create the color management transform.
          mTransform = qcms_transform_create(mInProfile,
                                          type,
                                          gfxPlatform::GetCMSOutputProfile(),
                                          QCMS_DATA_RGB_8,
                                          (qcms_intent)intent);
        }
      } else {
#ifdef DEBUG_tor
        fprintf(stderr, "ICM profile colorspace mismatch\n");
#endif
      }
    }

    if (!mTransform) {
      switch (mInfo.jpeg_color_space) {
        case JCS_GRAYSCALE:
        case JCS_RGB:
        case JCS_YCbCr:
          // if we're not color managing we can decode directly to
          // MOZ_JCS_EXT_NATIVE_ENDIAN_XRGB
          if (mCMSMode != eCMSMode_All) {
              mInfo.out_color_space = MOZ_JCS_EXT_NATIVE_ENDIAN_XRGB;
              mInfo.out_color_components = 4;
          } else {
              mInfo.out_color_space = JCS_RGB;
          }
          break;
        case JCS_CMYK:
        case JCS_YCCK:
          // libjpeg can convert from YCCK to CMYK, but not to RGB
          mInfo.out_color_space = JCS_CMYK;
          break;
        default:
          mState = JPEG_ERROR;
          PostDataError();
          PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
                 ("} (unknown colorpsace (3))"));
          return;
          break;
      }
    }

    // Don't allocate a giant and superfluous memory buffer
    // when not doing a progressive decode.
    mInfo.buffered_image = mDecodeStyle == PROGRESSIVE &&
                           jpeg_has_multiple_scans(&mInfo);

    if (!mImageData) {
      mState = JPEG_ERROR;
      PostDecoderError(NS_ERROR_OUT_OF_MEMORY);
      PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
             ("} (could not initialize image frame)"));
      return;
    }

    PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
           ("        JPEGDecoderAccounting: nsJPEGDecoder::"
            "Write -- created image frame with %ux%u pixels",
            mInfo.output_width, mInfo.output_height));

    mState = JPEG_START_DECOMPRESS;
  }

  case JPEG_START_DECOMPRESS: {
    LOG_SCOPE(GetJPEGLog(), "nsJPEGDecoder::Write -- entering"
                            " JPEG_START_DECOMPRESS case");
    // Step 4: set parameters for decompression

    // FIXME -- Should reset dct_method and dither mode
    // for final pass of progressive JPEG

    mInfo.dct_method =  JDCT_ISLOW;
    mInfo.dither_mode = JDITHER_FS;
    mInfo.do_fancy_upsampling = TRUE;
    mInfo.enable_2pass_quant = FALSE;
    mInfo.do_block_smoothing = TRUE;

    // Step 5: Start decompressor
    if (jpeg_start_decompress(&mInfo) == FALSE) {
      PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
             ("} (I/O suspension after jpeg_start_decompress())"));
      return; // I/O suspension
    }


    // If this is a progressive JPEG ...
    mState = mInfo.buffered_image ?
             JPEG_DECOMPRESS_PROGRESSIVE : JPEG_DECOMPRESS_SEQUENTIAL;
  }

  case JPEG_DECOMPRESS_SEQUENTIAL: {
    if (mState == JPEG_DECOMPRESS_SEQUENTIAL) {
      LOG_SCOPE(GetJPEGLog(), "nsJPEGDecoder::Write -- "
                              "JPEG_DECOMPRESS_SEQUENTIAL case");

      bool suspend;
      OutputScanlines(&suspend);

      if (suspend) {
        PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
               ("} (I/O suspension after OutputScanlines() - SEQUENTIAL)"));
        return; // I/O suspension
      }

      // If we've completed image output ...
      NS_ASSERTION(mInfo.output_scanline == mInfo.output_height,
                   "We didn't process all of the data!");
      mState = JPEG_DONE;
    }
  }

  case JPEG_DECOMPRESS_PROGRESSIVE: {
    if (mState == JPEG_DECOMPRESS_PROGRESSIVE) {
      LOG_SCOPE(GetJPEGLog(),
                "nsJPEGDecoder::Write -- JPEG_DECOMPRESS_PROGRESSIVE case");

      int status;
      do {
        status = jpeg_consume_input(&mInfo);
      } while ((status != JPEG_SUSPENDED) &&
               (status != JPEG_REACHED_EOI));

      for (;;) {
        if (mInfo.output_scanline == 0) {
          int scan = mInfo.input_scan_number;

          // if we haven't displayed anything yet (output_scan_number==0)
          // and we have enough data for a complete scan, force output
          // of the last full scan
          if ((mInfo.output_scan_number == 0) &&
              (scan > 1) &&
              (status != JPEG_REACHED_EOI))
            scan--;

          if (!jpeg_start_output(&mInfo, scan)) {
            PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
                   ("} (I/O suspension after jpeg_start_output() -"
                    " PROGRESSIVE)"));
            return; // I/O suspension
          }
        }

        if (mInfo.output_scanline == 0xffffff) {
          mInfo.output_scanline = 0;
        }

        bool suspend;
        OutputScanlines(&suspend);

        if (suspend) {
          if (mInfo.output_scanline == 0) {
            // didn't manage to read any lines - flag so we don't call
            // jpeg_start_output() multiple times for the same scan
            mInfo.output_scanline = 0xffffff;
          }
          PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
                 ("} (I/O suspension after OutputScanlines() - PROGRESSIVE)"));
          return; // I/O suspension
        }

        if (mInfo.output_scanline == mInfo.output_height) {
          if (!jpeg_finish_output(&mInfo)) {
            PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
                   ("} (I/O suspension after jpeg_finish_output() -"
                    " PROGRESSIVE)"));
            return; // I/O suspension
          }

          if (jpeg_input_complete(&mInfo) &&
              (mInfo.input_scan_number == mInfo.output_scan_number))
            break;

          mInfo.output_scanline = 0;
        }
      }

      mState = JPEG_DONE;
    }
  }

  case JPEG_DONE: {
    LOG_SCOPE(GetJPEGLog(), "nsJPEGDecoder::ProcessData -- entering"
                            " JPEG_DONE case");

    // Step 7: Finish decompression

    if (jpeg_finish_decompress(&mInfo) == FALSE) {
      PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
             ("} (I/O suspension after jpeg_finish_decompress() - DONE)"));
      return; // I/O suspension
    }

    mState = JPEG_SINK_NON_JPEG_TRAILER;

    // we're done dude
    break;
  }
  case JPEG_SINK_NON_JPEG_TRAILER:
    PR_LOG(GetJPEGLog(), PR_LOG_DEBUG,
           ("[this=%p] nsJPEGDecoder::ProcessData -- entering"
            " JPEG_SINK_NON_JPEG_TRAILER case\n", this));

    break;

  case JPEG_ERROR:
    NS_ABORT_IF_FALSE(0, "Should always return immediately after error and"
                         " not re-enter decoder");
  }

  PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
         ("} (end of function)"));
  return;
}
Пример #2
0
LexerTransition<nsJPEGDecoder::State>
nsJPEGDecoder::ReadJPEGData(const char* aData, size_t aLength)
{
  mSegment = reinterpret_cast<const JOCTET*>(aData);
  mSegmentLen = aLength;

  // Return here if there is a fatal error within libjpeg.
  nsresult error_code;
  // This cast to nsresult makes sense because setjmp() returns whatever we
  // passed to longjmp(), which was actually an nsresult.
  if ((error_code = static_cast<nsresult>(setjmp(mErr.setjmp_buffer))) != NS_OK) {
    if (error_code == NS_ERROR_FAILURE) {
      // Error due to corrupt data. Make sure that we don't feed any more data
      // to libjpeg-turbo.
      mState = JPEG_SINK_NON_JPEG_TRAILER;
      MOZ_LOG(sJPEGDecoderAccountingLog, LogLevel::Debug,
             ("} (setjmp returned NS_ERROR_FAILURE)"));
    } else {
      // Error for another reason. (Possibly OOM.)
      PostDecoderError(error_code);
      mState = JPEG_ERROR;
      MOZ_LOG(sJPEGDecoderAccountingLog, LogLevel::Debug,
             ("} (setjmp returned an error)"));
    }

    return Transition::TerminateFailure();
  }

  MOZ_LOG(sJPEGLog, LogLevel::Debug,
         ("[this=%p] nsJPEGDecoder::Write -- processing JPEG data\n", this));

  switch (mState) {
    case JPEG_HEADER: {
      LOG_SCOPE((mozilla::LogModule*)sJPEGLog, "nsJPEGDecoder::Write -- entering JPEG_HEADER"
                " case");

      // Step 3: read file parameters with jpeg_read_header()
      if (jpeg_read_header(&mInfo, TRUE) == JPEG_SUSPENDED) {
        MOZ_LOG(sJPEGDecoderAccountingLog, LogLevel::Debug,
               ("} (JPEG_SUSPENDED)"));
        return Transition::ContinueUnbuffered(State::JPEG_DATA); // I/O suspension
      }

      // If we have a sample size specified for -moz-sample-size, use it.
      if (mSampleSize > 0) {
        mInfo.scale_num = 1;
        mInfo.scale_denom = mSampleSize;
      }

      // Used to set up image size so arrays can be allocated
      jpeg_calc_output_dimensions(&mInfo);

      // Post our size to the superclass
      PostSize(mInfo.output_width, mInfo.output_height,
               ReadOrientationFromEXIF());
      if (HasError()) {
        // Setting the size led to an error.
        mState = JPEG_ERROR;
        return Transition::TerminateFailure();
      }

      // If we're doing a metadata decode, we're done.
      if (IsMetadataDecode()) {
        return Transition::TerminateSuccess();
      }

      // We're doing a full decode.
      if (mCMSMode != eCMSMode_Off &&
          (mInProfile = GetICCProfile(mInfo)) != nullptr) {
        uint32_t profileSpace = qcms_profile_get_color_space(mInProfile);
        bool mismatch = false;

#ifdef DEBUG_tor
      fprintf(stderr, "JPEG profileSpace: 0x%08X\n", profileSpace);
#endif
      switch (mInfo.jpeg_color_space) {
        case JCS_GRAYSCALE:
          if (profileSpace == icSigRgbData) {
            mInfo.out_color_space = JCS_RGB;
          } else if (profileSpace != icSigGrayData) {
            mismatch = true;
          }
          break;
        case JCS_RGB:
          if (profileSpace != icSigRgbData) {
            mismatch =  true;
          }
          break;
        case JCS_YCbCr:
          if (profileSpace == icSigRgbData) {
            mInfo.out_color_space = JCS_RGB;
          } else {
            // qcms doesn't support ycbcr
            mismatch = true;
          }
          break;
        case JCS_CMYK:
        case JCS_YCCK:
            // qcms doesn't support cmyk
            mismatch = true;
          break;
        default:
          mState = JPEG_ERROR;
          PostDataError();
          MOZ_LOG(sJPEGDecoderAccountingLog, LogLevel::Debug,
                 ("} (unknown colorpsace (1))"));
          return Transition::TerminateFailure();
      }

      if (!mismatch) {
        qcms_data_type type;
        switch (mInfo.out_color_space) {
          case JCS_GRAYSCALE:
            type = QCMS_DATA_GRAY_8;
            break;
          case JCS_RGB:
            type = QCMS_DATA_RGB_8;
            break;
          default:
            mState = JPEG_ERROR;
            PostDataError();
            MOZ_LOG(sJPEGDecoderAccountingLog, LogLevel::Debug,
                   ("} (unknown colorpsace (2))"));
            return Transition::TerminateFailure();
        }
#if 0
        // We don't currently support CMYK profiles. The following
        // code dealt with lcms types. Add something like this
        // back when we gain support for CMYK.

        // Adobe Photoshop writes YCCK/CMYK files with inverted data
        if (mInfo.out_color_space == JCS_CMYK) {
          type |= FLAVOR_SH(mInfo.saw_Adobe_marker ? 1 : 0);
        }
#endif

        if (gfxPlatform::GetCMSOutputProfile()) {

          // Calculate rendering intent.
          int intent = gfxPlatform::GetRenderingIntent();
          if (intent == -1) {
            intent = qcms_profile_get_rendering_intent(mInProfile);
          }

          // Create the color management transform.
          mTransform = qcms_transform_create(mInProfile,
                                          type,
                                          gfxPlatform::GetCMSOutputProfile(),
                                          QCMS_DATA_RGB_8,
                                          (qcms_intent)intent);
        }
      } else {
#ifdef DEBUG_tor
        fprintf(stderr, "ICM profile colorspace mismatch\n");
#endif
      }
    }

    if (!mTransform) {
      switch (mInfo.jpeg_color_space) {
        case JCS_GRAYSCALE:
        case JCS_RGB:
        case JCS_YCbCr:
          // if we're not color managing we can decode directly to
          // MOZ_JCS_EXT_NATIVE_ENDIAN_XRGB
          if (mCMSMode != eCMSMode_All) {
              mInfo.out_color_space = MOZ_JCS_EXT_NATIVE_ENDIAN_XRGB;
              mInfo.out_color_components = 4;
          } else {
              mInfo.out_color_space = JCS_RGB;
          }
          break;
        case JCS_CMYK:
        case JCS_YCCK:
          // libjpeg can convert from YCCK to CMYK, but not to RGB
          mInfo.out_color_space = JCS_CMYK;
          break;
        default:
          mState = JPEG_ERROR;
          PostDataError();
          MOZ_LOG(sJPEGDecoderAccountingLog, LogLevel::Debug,
                 ("} (unknown colorpsace (3))"));
          return Transition::TerminateFailure();
      }
    }

    // Don't allocate a giant and superfluous memory buffer
    // when not doing a progressive decode.
    mInfo.buffered_image = mDecodeStyle == PROGRESSIVE &&
                           jpeg_has_multiple_scans(&mInfo);

    MOZ_ASSERT(!mImageData, "Already have a buffer allocated?");
    nsIntSize targetSize = mDownscaler ? mDownscaler->TargetSize() : GetSize();
    nsresult rv = AllocateFrame(0, targetSize,
                                nsIntRect(nsIntPoint(), targetSize),
                                gfx::SurfaceFormat::B8G8R8A8);
    if (NS_FAILED(rv)) {
      mState = JPEG_ERROR;
      MOZ_LOG(sJPEGDecoderAccountingLog, LogLevel::Debug,
             ("} (could not initialize image frame)"));
      return Transition::TerminateFailure();
    }

    MOZ_ASSERT(mImageData, "Should have a buffer now");

    if (mDownscaler) {
      nsresult rv = mDownscaler->BeginFrame(GetSize(), Nothing(),
                                            mImageData,
                                            /* aHasAlpha = */ false);
      if (NS_FAILED(rv)) {
        mState = JPEG_ERROR;
        return Transition::TerminateFailure();
      }
    }

    MOZ_LOG(sJPEGDecoderAccountingLog, LogLevel::Debug,
           ("        JPEGDecoderAccounting: nsJPEGDecoder::"
            "Write -- created image frame with %ux%u pixels",
            mInfo.output_width, mInfo.output_height));

    mState = JPEG_START_DECOMPRESS;
    MOZ_FALLTHROUGH; // to start decompressing.
  }

  case JPEG_START_DECOMPRESS: {
    LOG_SCOPE((mozilla::LogModule*)sJPEGLog, "nsJPEGDecoder::Write -- entering"
                            " JPEG_START_DECOMPRESS case");
    // Step 4: set parameters for decompression

    // FIXME -- Should reset dct_method and dither mode
    // for final pass of progressive JPEG

    mInfo.dct_method =  JDCT_ISLOW;
    mInfo.dither_mode = JDITHER_FS;
    mInfo.do_fancy_upsampling = TRUE;
    mInfo.enable_2pass_quant = FALSE;
    mInfo.do_block_smoothing = TRUE;

    // Step 5: Start decompressor
    if (jpeg_start_decompress(&mInfo) == FALSE) {
      MOZ_LOG(sJPEGDecoderAccountingLog, LogLevel::Debug,
             ("} (I/O suspension after jpeg_start_decompress())"));
      return Transition::ContinueUnbuffered(State::JPEG_DATA); // I/O suspension
    }

    // If this is a progressive JPEG ...
    mState = mInfo.buffered_image ?
             JPEG_DECOMPRESS_PROGRESSIVE : JPEG_DECOMPRESS_SEQUENTIAL;
    MOZ_FALLTHROUGH; // to decompress sequential JPEG.
  }

  case JPEG_DECOMPRESS_SEQUENTIAL: {
    if (mState == JPEG_DECOMPRESS_SEQUENTIAL) {
      LOG_SCOPE((mozilla::LogModule*)sJPEGLog, "nsJPEGDecoder::Write -- "
                              "JPEG_DECOMPRESS_SEQUENTIAL case");

      bool suspend;
      OutputScanlines(&suspend);

      if (suspend) {
        MOZ_LOG(sJPEGDecoderAccountingLog, LogLevel::Debug,
               ("} (I/O suspension after OutputScanlines() - SEQUENTIAL)"));
        return Transition::ContinueUnbuffered(State::JPEG_DATA); // I/O suspension
      }

      // If we've completed image output ...
      NS_ASSERTION(mInfo.output_scanline == mInfo.output_height,
                   "We didn't process all of the data!");
      mState = JPEG_DONE;
    }
    MOZ_FALLTHROUGH; // to decompress progressive JPEG.
  }

  case JPEG_DECOMPRESS_PROGRESSIVE: {
    if (mState == JPEG_DECOMPRESS_PROGRESSIVE) {
      LOG_SCOPE((mozilla::LogModule*)sJPEGLog,
                "nsJPEGDecoder::Write -- JPEG_DECOMPRESS_PROGRESSIVE case");

      int status;
      do {
        status = jpeg_consume_input(&mInfo);
      } while ((status != JPEG_SUSPENDED) &&
               (status != JPEG_REACHED_EOI));

      for (;;) {
        if (mInfo.output_scanline == 0) {
          int scan = mInfo.input_scan_number;

          // if we haven't displayed anything yet (output_scan_number==0)
          // and we have enough data for a complete scan, force output
          // of the last full scan
          if ((mInfo.output_scan_number == 0) &&
              (scan > 1) &&
              (status != JPEG_REACHED_EOI))
            scan--;

          if (!jpeg_start_output(&mInfo, scan)) {
            MOZ_LOG(sJPEGDecoderAccountingLog, LogLevel::Debug,
                   ("} (I/O suspension after jpeg_start_output() -"
                    " PROGRESSIVE)"));
            return Transition::ContinueUnbuffered(State::JPEG_DATA); // I/O suspension
          }
        }

        if (mInfo.output_scanline == 0xffffff) {
          mInfo.output_scanline = 0;
        }

        bool suspend;
        OutputScanlines(&suspend);

        if (suspend) {
          if (mInfo.output_scanline == 0) {
            // didn't manage to read any lines - flag so we don't call
            // jpeg_start_output() multiple times for the same scan
            mInfo.output_scanline = 0xffffff;
          }
          MOZ_LOG(sJPEGDecoderAccountingLog, LogLevel::Debug,
                 ("} (I/O suspension after OutputScanlines() - PROGRESSIVE)"));
          return Transition::ContinueUnbuffered(State::JPEG_DATA); // I/O suspension
        }

        if (mInfo.output_scanline == mInfo.output_height) {
          if (!jpeg_finish_output(&mInfo)) {
            MOZ_LOG(sJPEGDecoderAccountingLog, LogLevel::Debug,
                   ("} (I/O suspension after jpeg_finish_output() -"
                    " PROGRESSIVE)"));
            return Transition::ContinueUnbuffered(State::JPEG_DATA); // I/O suspension
          }

          if (jpeg_input_complete(&mInfo) &&
              (mInfo.input_scan_number == mInfo.output_scan_number))
            break;

          mInfo.output_scanline = 0;
          if (mDownscaler) {
            mDownscaler->ResetForNextProgressivePass();
          }
        }
      }

      mState = JPEG_DONE;
    }
    MOZ_FALLTHROUGH; // to finish decompressing.
  }

  case JPEG_DONE: {
    LOG_SCOPE((mozilla::LogModule*)sJPEGLog, "nsJPEGDecoder::ProcessData -- entering"
                            " JPEG_DONE case");

    // Step 7: Finish decompression

    if (jpeg_finish_decompress(&mInfo) == FALSE) {
      MOZ_LOG(sJPEGDecoderAccountingLog, LogLevel::Debug,
             ("} (I/O suspension after jpeg_finish_decompress() - DONE)"));
      return Transition::ContinueUnbuffered(State::JPEG_DATA); // I/O suspension
    }

    // Make sure we don't feed any more data to libjpeg-turbo.
    mState = JPEG_SINK_NON_JPEG_TRAILER;

    // We're done.
    return Transition::TerminateSuccess();
  }
  case JPEG_SINK_NON_JPEG_TRAILER:
    MOZ_LOG(sJPEGLog, LogLevel::Debug,
           ("[this=%p] nsJPEGDecoder::ProcessData -- entering"
            " JPEG_SINK_NON_JPEG_TRAILER case\n", this));

    MOZ_ASSERT_UNREACHABLE("Should stop getting data after entering state "
                           "JPEG_SINK_NON_JPEG_TRAILER");

    return Transition::TerminateSuccess();

  case JPEG_ERROR:
    MOZ_ASSERT_UNREACHABLE("Should stop getting data after entering state "
                           "JPEG_ERROR");

    return Transition::TerminateFailure();
  }

  MOZ_ASSERT_UNREACHABLE("Escaped the JPEG decoder state machine");
  return Transition::TerminateFailure();
}