Add compile options for the EAGLE star model

configure.ac

@@ -1581,7 +1581,7 @@ esac
 # Stellar model.
 AC_ARG_WITH([stars],
    [AS_HELP_STRING([--with-stars=<model>],
-      [Stellar model to use @<:@none, GEAR, debug default: none@:>@]
+      [Stellar model to use @<:@none, EAGLE, GEAR, debug default: none@:>@]
    )],
    [with_stars="$withval"],
    [with_stars="none"]
@@ -1596,10 +1596,14 @@ if test "$with_subgrid" != "none"; then
 fi
 
 case "$with_stars" in
+   EAGLE)
+      AC_DEFINE([STARS_EAGLE], [1], [EAGLE stellar model])
+   ;;
    GEAR)
       AC_DEFINE([STARS_GEAR], [1], [GEAR stellar model])
    ;;
    none)
+      AC_DEFINE([STARS_NONE], [1], [None stellar model])
    ;;
 
    *)

src/stars.h

@@ -22,9 +22,18 @@
 /* Config parameters. */
 #include "../config.h"
 
-/* So far only one model here */
-/* Straight-forward import */
+/* Select the correct star model */
+#if defined(STARS_NONE)
 #include "./stars/Default/stars.h"
 #include "./stars/Default/stars_iact.h"
+#elif defined(STARS_EAGLE)
+#include "./stars/EAGLE/stars.h"
+#include "./stars/EAGLE/stars_iact.h" 
+#elif defined(STARS_GEAR)
+#include "./stars/GEAR/stars.h" 
+#include "./stars/GEAR/stars_iact.h"
+#else 
+#error "Invalid choice of star model" 
+#endif
 
 #endif