Scanline decoding for bmp

src/codec/SkBmpRLECodec.cpp

Index: src/codec/SkBmpRLECodec.cpp
diff --git a/src/codec/SkBmpRLECodec.cpp b/src/codec/SkBmpRLECodec.cpp
index c71a5409d2c2c2ee5d2fa11261594c809f4c66d1..4d7a66373472762dba1b61d22cc3ca17264ec665 100644
--- a/src/codec/SkBmpRLECodec.cpp
+++ b/src/codec/SkBmpRLECodec.cpp
@@ -45,10 +45,11 @@ static bool conversion_possible(const SkImageInfo& dst,
  * Called only by NewFromStream
  */
 SkBmpRLECodec::SkBmpRLECodec(const SkImageInfo& info, SkStream* stream,
+                             SkBmpCodec::BmpInputFormat inputFormat,
                              uint16_t bitsPerPixel, uint32_t numColors,
                              uint32_t bytesPerColor, uint32_t offset,
                              SkBmpCodec::RowOrder rowOrder, size_t RLEBytes)
-    : INHERITED(info, stream, bitsPerPixel, rowOrder)
+    : INHERITED(info, stream, inputFormat, bitsPerPixel, rowOrder)
     , fColorTable(NULL)
     , fNumColors(this->computeNumColors(numColors))
     , fBytesPerColor(bytesPerColor)
@@ -475,3 +476,24 @@ SkCodec::Result SkBmpRLECodec::decode(const SkImageInfo& dstInfo,
         }
     }
 }
+
+SkCodec::Result SkBmpRLECodec::onStart(const SkImageInfo& dstInfo,
+        const SkCodec::Options& options, SkPMColor inputColorPtr[], int* inputColorCount) {
+    // Create the color table if necessary and prepare the stream for decode
+    // Note that if it is non-NULL, inputColorCount will be modified
+    if (!this->createColorTable(inputColorCount)) {
+        SkCodecPrintf("Error: could not create color table.\n");
+        return SkCodec::kInvalidInput;
+    }
+
+    // Copy the color table to the client if necessary
+    copy_color_table(dstInfo, this->fColorTable, inputColorPtr, inputColorCount);
+
+    // Initialize a buffer for encoded RLE data
+    if (!this->initializeStreamBuffer()) {
+        SkCodecPrintf("Error: cannot initialize swizzler.\n");
+        return SkCodec::kInvalidConversion;
+    }
+
+    return SkCodec::kSuccess;
+}