Bmp Image Decoding

src/codec/SkCodec.cpp

Index: src/codec/SkCodec.cpp
diff --git a/src/codec/SkCodec.cpp b/src/codec/SkCodec.cpp
index 69d95a41da24be0231cdd32b8719d2b1d6ea3747..75c0ca1244c308d6b9f84ddfd315c295808477f3 100644
--- a/src/codec/SkCodec.cpp
+++ b/src/codec/SkCodec.cpp
@@ -7,6 +7,7 @@
 
 #include "SkCodec.h"
 #include "SkData.h"
+#include "SkCodec_libbmp.h"
 #include "SkCodec_libpng.h"
 #include "SkStream.h"
 
@@ -15,6 +16,14 @@ SkCodec* SkCodec::NewFromStream(SkStream* stream) {
         return NULL;
     }
     SkAutoTDelete<SkStream> streamDeleter(stream);
+    const bool isBmp = SkBmpCodec::IsBmp(stream);
+    if (!stream->rewind()) {
+        return NULL;
+    }
+    if (isBmp) {
+        streamDeleter.detach();
+        return SkBmpCodec::NewFromStream(stream);
+    }
     const bool isPng = SkPngCodec::IsPng(stream);

[scroggo, 2015/03/06 18:56:12]

nit: PNG should be first, since we'll see more PNG images.

That said, This function is going to quickly get out of hand. I think we should
take some advice from the old method in SkImageDecoder_Factory.

Something like:

struct DecoderProc {
  bool (*IsFormat)(SkStream*);
  SkCodec* (*NewFromStream)(SkStream*);
};

static const DecoderProc gDecoderProcs[] = {
  { SkPngCodec::IsPng, SkPngCodec::NewFromStream },
  { SkBmpCodec::IsBmp, SkBmpCodec::NewFromStream }
};

// Inside NewFromStream
for (proc in gDecoderProcs) {
  const bool correctFormat = proc.IsFormat(stream);
  if (!stream->rewind()) {
    return NULL;
  }
  if (correctFormat) {
    return proc.NewFromStream(stream);
  }
}
return NULL;

     if (!stream->rewind()) {
         return NULL;