Scanline decoding for bmp

src/codec/SkBmpMaskCodec.h

 /*
  * 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 "SkBmpCodec.h"
 #include "SkImageInfo.h"
 #include "SkMaskSwizzler.h"
@@ skipping 11 matching lines @@
      * Called only by SkBmpCodec::NewFromStream
      * There should be no other callers despite this being public
      *
      * @param srcInfo contains the source width and height
      * @param stream the stream of encoded image data
      * @param bitsPerPixel the number of bits used to store each pixel
      * @param masks color masks for certain bmp formats
      * @param rowOrder indicates whether rows are ordered top-down or bottom-up
      */
     SkBmpMaskCodec(const SkImageInfo& srcInfo, SkStream* stream,
-                   uint16_t bitsPerPixel, SkMasks* masks, RowOrder rowOrder);
+            SkBmpCodec::BmpInputFormat inputFormat, uint16_t bitsPerPixel,
+            SkMasks* masks, RowOrder rowOrder);
 
 protected:
 
     Result onGetPixels(const SkImageInfo& dstInfo, void* dst,
                        size_t dstRowBytes, const Options&, SkPMColor*,
                        int*) override;
 
 private:
 
     bool initializeSwizzler(const SkImageInfo& dstInfo);
 
     Result decode(const SkImageInfo& dstInfo, void* dst, size_t dstRowBytes,
                   const Options& opts);
 
     SkAutoTDelete<SkMasks>              fMasks;        // owned
     SkAutoTDelete<SkMaskSwizzler>       fMaskSwizzler;
     SkAutoTDeleteArray<uint8_t>         fSrcBuffer;
 
+    friend class SkBmpMaskScanlineDecoder;
+
     typedef SkBmpCodec INHERITED;
 };
+
+/*
+ * Scanline decoder for mask bmps
+ */
+class SkBmpMaskScanlineDecoder : public SkScanlineDecoder {
+public:
+    SkBmpMaskScanlineDecoder(SkBmpMaskCodec* codec);
+
+    SkCodec::Result onStart(const SkImageInfo& dstInfo, const SkCodec::Options& options,
+                            SkPMColor inputColorPtr[], int* inputColorCount) override;
+
+    SkCodec::Result onGetScanlines(void* dst, int count, size_t rowBytes) override;
+
+    // TODO(msarett): Override default skipping with something more clever.
+    // TODO(msarett): Consider other optimizations for this codec.
+
+private:
+    SkAutoTDelete<SkBmpMaskCodec>     fCodec;
+    SkImageInfo                       fDstInfo;
+    SkCodec::Options                  fOpts;
+
+    typedef SkScanlineDecoder INHERITED;
+};