read/write function_ptrs as just void*, and not as 'array of bytes'

include/core/SkReadBuffer.h

Index: include/core/SkReadBuffer.h
diff --git a/include/core/SkReadBuffer.h b/include/core/SkReadBuffer.h
index 3cb31a0e809c2e2f9b61e8f912d370f544f3f66d..f6b1919133a2307764bb743e035e6b84f645067e 100644
--- a/include/core/SkReadBuffer.h
+++ b/include/core/SkReadBuffer.h
@@ -73,6 +73,7 @@ public:
     uint32_t offset() { return fReader.offset(); }
     bool eof() { return fReader.eof(); }
     const void* skip(size_t size) { return fReader.skip(size); }
+    void* readFunctionPtr() { return fReader.readPtr(); }

[bungeman-skia, 2014/04/16 16:51:36]

So, I think this was 'incorrect' before, so this change makes no real
difference. However, it is technically undefined to cast a function pointer to a
void pointer. POSIX defines the way we do things in the call to dlsym in
SkFontHost_FreeType.cpp (because dlsym is defined to return a void*). Windows is
actually better here, as GetProcAddress returns FARPROC which is actually a
function pointer.

The spec does state that you can cast a function pointer to another one, so long
as it is cast back to the original before making a call through it. I would
propose a 'typedef void (*SkVoidProc)()' which would be what this and the
associated writer would deal in.

 
     // primitives
     virtual bool readBool();
@@ -83,12 +84,6 @@ public:
     virtual uint32_t readUInt();
     virtual int32_t read32();
 
-    void* readFunctionPtr() {
-        void* ptr;
-        this->readByteArray(&ptr, sizeof(ptr));
-        return ptr;
-    }
-
     // strings -- the caller is responsible for freeing the string contents
     virtual void readString(SkString* string);
     virtual void* readEncodedString(size_t* length, SkPaint::TextEncoding encoding);