michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
michael@0:  *
michael@0:  * This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "nsIconDecoder.h"
michael@0: #include "nsIInputStream.h"
michael@0: #include "RasterImage.h"
michael@0: #include "nspr.h"
michael@0: #include "nsRect.h"
michael@0: 
michael@0: #include "nsError.h"
michael@0: #include <algorithm>
michael@0: 
michael@0: namespace mozilla {
michael@0: namespace image {
michael@0: 
michael@0: nsIconDecoder::nsIconDecoder(RasterImage &aImage)
michael@0:  : Decoder(aImage),
michael@0:    mWidth(-1),
michael@0:    mHeight(-1),
michael@0:    mPixBytesRead(0),
michael@0:    mState(iconStateStart)
michael@0: {
michael@0:   // Nothing to do
michael@0: }
michael@0: 
michael@0: nsIconDecoder::~nsIconDecoder()
michael@0: { }
michael@0: 
michael@0: void
michael@0: nsIconDecoder::WriteInternal(const char *aBuffer, uint32_t aCount, DecodeStrategy)
michael@0: {
michael@0:   NS_ABORT_IF_FALSE(!HasError(), "Shouldn't call WriteInternal after error!");
michael@0: 
michael@0:   // We put this here to avoid errors about crossing initialization with case
michael@0:   // jumps on linux.
michael@0:   uint32_t bytesToRead = 0;
michael@0: 
michael@0:   // Loop until the input data is gone
michael@0:   while (aCount > 0) {
michael@0:     switch (mState) {
michael@0:       case iconStateStart:
michael@0: 
michael@0:         // Grab the width
michael@0:         mWidth = (uint8_t)*aBuffer;
michael@0: 
michael@0:         // Book Keeping
michael@0:         aBuffer++;
michael@0:         aCount--;
michael@0:         mState = iconStateHaveHeight;
michael@0:         break;
michael@0: 
michael@0:       case iconStateHaveHeight:
michael@0: 
michael@0:         // Grab the Height
michael@0:         mHeight = (uint8_t)*aBuffer;
michael@0: 
michael@0:         // Post our size to the superclass
michael@0:         PostSize(mWidth, mHeight);
michael@0:         if (HasError()) {
michael@0:           // Setting the size led to an error.
michael@0:           mState = iconStateFinished;
michael@0:           return;
michael@0:         }
michael@0: 
michael@0:         // If We're doing a size decode, we're done
michael@0:         if (IsSizeDecode()) {
michael@0:           mState = iconStateFinished;
michael@0:           break;
michael@0:         }
michael@0: 
michael@0:         if (!mImageData) {
michael@0:           PostDecoderError(NS_ERROR_OUT_OF_MEMORY);
michael@0:           return;
michael@0:         }
michael@0: 
michael@0:         // Book Keeping
michael@0:         aBuffer++;
michael@0:         aCount--;
michael@0:         mState = iconStateReadPixels;
michael@0:         break;
michael@0: 
michael@0:       case iconStateReadPixels:
michael@0:       {
michael@0: 
michael@0:         // How many bytes are we reading?
michael@0:         bytesToRead = std::min(aCount, mImageDataLength - mPixBytesRead);
michael@0: 
michael@0:         // Copy the bytes
michael@0:         memcpy(mImageData + mPixBytesRead, aBuffer, bytesToRead);
michael@0: 
michael@0:         // Performance isn't critical here, so our update rectangle is
michael@0:         // always the full icon
michael@0:         nsIntRect r(0, 0, mWidth, mHeight);
michael@0: 
michael@0:         // Invalidate
michael@0:         PostInvalidation(r);
michael@0: 
michael@0:         // Book Keeping
michael@0:         aBuffer += bytesToRead;
michael@0:         aCount -= bytesToRead;
michael@0:         mPixBytesRead += bytesToRead;
michael@0: 
michael@0:         // If we've got all the pixel bytes, we're finished
michael@0:         if (mPixBytesRead == mImageDataLength) {
michael@0:           PostFrameStop();
michael@0:           PostDecodeDone();
michael@0:           mState = iconStateFinished;
michael@0:         }
michael@0:         break;
michael@0:       }
michael@0: 
michael@0:       case iconStateFinished:
michael@0: 
michael@0:         // Consume all excess data silently
michael@0:         aCount = 0;
michael@0: 
michael@0:         break;
michael@0:     }
michael@0:   }
michael@0: }
michael@0: 
michael@0: } // namespace image
michael@0: } // namespace mozilla