MAINT-6584: Streamline static LLImageJ2C implementation API.

Specifically, remove unused function pointer types CreateLLImageJ2CFunction,
DestroyLLImageJ2CFunction and EngineInfoLLImageJ2CFunction.

Also eliminate static fallbackDestroyLLImageJ2CImpl() and
fallbackEngineInfoLLImageJ2CImpl(), leaving only static
fallbackCreateLLImageJ2CImpl().

We do need a factory function to instantiate the appropriate LLImageJ2CImpl
subclass, so leave the fallbackCreateLLImageJ2CImpl() link seam in place.

However, given that every known LLImageJ2CImpl subclass is cheap to
instantiate, make getEngineInfo() a pure virtual method on that subclass: the
static LLImageJ2C::getEngineInfo() method can temporarily construct an
instance to query. While we're at it, make getEngineInfo() return std::string
like LLImageJ2C::getEngineInfo(). It's ridiculous that
fallbackEngineInfoLLImageJ2CImpl() implementations constructed a static
std::string and returned its c_str(), only to have LLImageJ2C::getEngineInfo()
construct ANOTHER std::string from the returned const char*.

fallbackDestroyLLImageJ2CImpl() never did anything useful: it merely deleted
the passed LLImageJ2CImpl subclass pointer as the specific subclass type. But
since LLImageJ2CImpl's destructor is virtual, LLImageJ2C's destructor could
simply delete the stored LLImageJ2CImpl*. In fact, make mImpl a
boost::scoped_ptr<LLImageJ2CImpl> so we don't even have to delete it manually.

1 files changed, 4 insertions, 3 deletions

diff --git a/indra/llimage/llimagej2c.h b/indra/llimage/llimagej2c.h
index ce8195940d..bfaccdfd05 100644
--- a/indra/llimage/llimagej2c.h
+++ b/indra/llimage/llimagej2c.h
@@ -30,6 +30,7 @@
 #include "llimage.h"
 #include "llassettype.h"
 #include "llmetricperformancetester.h"
+#include <boost/scoped_ptr.hpp>
 
 // JPEG2000 : compression rate used in j2c conversion.
 const F32 DEFAULT_COMPRESSION_RATE = 1.f/8.f;
@@ -94,7 +95,7 @@ protected:
 	S8  mRawDiscardLevel;
 	F32 mRate;
 	BOOL mReversible;
-	LLImageJ2CImpl *mImpl;
+	boost::scoped_ptr<LLImageJ2CImpl> mImpl;
 	std::string mLastError;
 
     // Image compression/decompression tester
@@ -124,11 +125,11 @@ protected:
 	virtual BOOL initDecode(LLImageJ2C &base, LLImageRaw &raw_image, int discard_level = -1, int* region = NULL) = 0;
 	virtual BOOL initEncode(LLImageJ2C &base, LLImageRaw &raw_image, int blocks_size = -1, int precincts_size = -1, int levels = 0) = 0;
 
+	virtual std::string getEngineInfo() const = 0;
+
 	friend class LLImageJ2C;
 };
 
-#define LINDEN_J2C_COMMENT_PREFIX "LL_"
-
 //
 // This class is used for performance data gathering only.
 // Tracks the image compression / decompression data,