Scanline decoding for bmp

src/codec/SkBmpCodec.h

Index: src/codec/SkBmpCodec.h
diff --git a/src/codec/SkBmpCodec.h b/src/codec/SkBmpCodec.h
index 71006f73153ea3028529b0c51daa999b498bc86e..8a5066b4f49917547176499731c1b6fccab3813f 100644
--- a/src/codec/SkBmpCodec.h
+++ b/src/codec/SkBmpCodec.h
@@ -11,6 +11,7 @@
 #include "SkColorTable.h"
 #include "SkImageInfo.h"
 #include "SkMaskSwizzler.h"
+#include "SkScanlineDecoder.h"
 #include "SkStream.h"
 #include "SkSwizzler.h"
 #include "SkTypes.h"
@@ -31,6 +32,16 @@ public:
     };
 
     /*
+     * Used to define the input format of the bmp
+     */
+    enum BmpInputFormat {
+        kStandard_BmpInputFormat,
+        kRLE_BmpInputFormat,
+        kBitMask_BmpInputFormat,
+        kUnknown_BmpInputFormat
+    };
+
+    /*
      * Checks the start of the stream to see if the image is a bmp
      */
     static bool IsBmp(SkStream*);
@@ -48,10 +59,17 @@ public:
      */
     static SkCodec* NewFromIco(SkStream*);
 
+    /*
+     * Assumes IsBmp was called and returned true
+     * Creates a bmp scanline decoder
+     * Takes ownership of the stream
+     */
+    static SkScanlineDecoder* NewSDFromStream(SkStream* stream);
+
 protected:
 
-    SkBmpCodec(const SkImageInfo& info, SkStream* stream, uint16_t bitsPerPixel,
-            RowOrder rowOrder);
+    SkBmpCodec(const SkImageInfo& info, SkStream* stream, BmpInputFormat inputFormat,
+            uint16_t bitsPerPixel, RowOrder rowOrder);
 
     SkEncodedFormat onGetEncodedFormat() const override { return kBMP_SkEncodedFormat; }
 
@@ -104,8 +122,9 @@ private:
      */
     static SkCodec* NewFromStream(SkStream*, bool inIco);
 
-    const uint16_t fBitsPerPixel;
-    const RowOrder fRowOrder;
+    const BmpInputFormat fInputFormat;
+    const uint16_t       fBitsPerPixel;
+    const RowOrder       fRowOrder;
 
     typedef SkCodec INHERITED;
 };