R DLL/SO not required (!)

.. we can register routines when embedding via the
   R_getEmbeddingDLLInfo()

.. so we just register our functions directly now
   in RTool rather than needing a dynamic library.

.. its cleaner and there are no nasty casts and build
   settings required

deprecated/RGoldenCheetah.c

@@ -0,0 +1,80 @@
+// R API is C
+#include <R.h>
+#include <Rinternals.h>
+#include <R_ext/Rdynload.h>
+
+// an array of pointers to the actual functions
+// in the native GC code -- these are initialised
+// once the shared library has been loaded via
+// a call to initialiseFunctions()
+//
+// for this test we only have one function
+// GC.display() to make sure the concept works
+static SEXP (*fn[6])();
+
+// if we haven't been initialised don't even try
+// to dereference the function pointers !!
+static int initialised = 0;
+
+// stub methods, call the GC routines if they've been initialised
+SEXP GCdisplay() { if (initialised) return fn[0](); else return NULL; }
+SEXP GCathlete() { if (initialised) return fn[1](); else return NULL; }
+SEXP GCathleteHome() { if (initialised) return fn[2](); else return NULL; }
+SEXP GCactivities() { if (initialised) return fn[3](); else return NULL; }
+SEXP GCactivity() { if (initialised) return fn[4](); else return NULL; }
+SEXP GCmetrics() { if (initialised) return fn[5](); else return NULL; }
+
+SEXP GCinitialiseFunctions(SEXP (*functions[1])())
+{
+    //fprintf(stderr, "RGoldenCheetah initialise functions\n");
+
+    // initialise all the function pointers
+    for(int i=0; i<6; i++) fn[i] = functions[i];
+    initialised = 1;
+
+    return 0;
+}
+
+// this function is called by R when the dynamic library
+// is loaded via the R command > dyn.load("RGoldenCheetah.so")
+// and is expected to register all the C functions to make
+// available via the C interface
+//
+// By return, a number of functions will be created that provide
+// wrappers in R (i.e. they call with the .C(xxx) notation and
+//
+// We so this to avoid using Rcpp / RInside which are not
+// compatible with MSVC
+void
+R_init_RGoldenCheetah(DllInfo *info)
+{
+    //fprintf(stderr, "RGoldenCheetah init is called!\n");
+
+    // initialise the parameter table
+    R_CMethodDef cMethods[] = {
+        { "GCinitialiseFunctions", (DL_FUNC) &GCinitialiseFunctions, 0 },
+        { "GC.display", (DL_FUNC) &GCdisplay, 0 },
+        { "GC.athlete", (DL_FUNC) &GCathlete, 0 },
+        { "GC.athlete.home", (DL_FUNC) &GCathleteHome, 0 },
+        { "GC.activities", (DL_FUNC) &GCactivities, 0 },
+        { "GC.activity", (DL_FUNC) &GCactivity, 0 },
+        { "GC.metrics", (DL_FUNC) &GCmetrics, 0 },
+        { NULL, NULL, 0 }
+    };
+    R_CallMethodDef callMethods[] = {
+        { "GCinitialiseFunctions", (DL_FUNC) &GCinitialiseFunctions, 0 },
+        { "GC.display", (DL_FUNC) &GCdisplay, 0 },
+        { "GC.athlete", (DL_FUNC) &GCathlete, 0 },
+        { "GC.athlete.home", (DL_FUNC) &GCathleteHome, 0 },
+        { "GC.activities", (DL_FUNC) &GCactivities, 0 },
+        { "GC.activity", (DL_FUNC) &GCactivity, 0 },
+        { "GC.metrics", (DL_FUNC) &GCmetrics, 0 },
+        { NULL, NULL, 0 }
+    };
+
+    // set them up
+    R_registerRoutines(info, cMethods, callMethods, NULL, NULL);
+
+    // make the initialiseFunctions callable from C
+    R_RegisterCCallable("RGoldenCheetah", "GCinitialiseFunctions", (DL_FUNC)&GCinitialiseFunctions);
+}