7178922: (props) re-visit how os.name is determined on Mac

Reviewed-by: alanb, mchung, skovatch, serb

src/solaris/native/java/lang/java_props_macosx.c

@@ -145,27 +145,22 @@ PreferredToolkit getPreferredToolkit() {
     return pref = HToolkit;
 }
 
-void setUnknownOSAndVersion(java_props_t *sprops) {
-    sprops->os_name = strdup("Unknown");
-    sprops->os_version = strdup("Unknown");
-}
-
 void setOSNameAndVersion(java_props_t *sprops) {
-    void *jrsFwk = getJRSFramework();
-    if (jrsFwk == NULL) {
-        setUnknownOSAndVersion(sprops);
-        return;
-    }
+    /* Don't rely on JRSCopyOSName because there's no guarantee the value will
+     * remain the same, or even if the JRS functions will continue to be part of
+     * Mac OS X.  So hardcode os_name, and fill in os_version if we can.
+     */
+    sprops->os_name = strdup("Mac OS X");
 
-    char *(*copyOSName)() = dlsym(jrsFwk, "JRSCopyOSName");
-    char *(*copyOSVersion)() = dlsym(jrsFwk, "JRSCopyOSVersion");
-    if (copyOSName == NULL || copyOSVersion == NULL) {
-        setUnknownOSAndVersion(sprops);
-        return;
+    void *jrsFwk = getJRSFramework();
+    if (jrsFwk != NULL) {
+        char *(*copyOSVersion)() = dlsym(jrsFwk, "JRSCopyOSVersion");
+        if (copyOSVersion != NULL) {
+            sprops->os_version = copyOSVersion();
+            return;
+        }
     }
-
-    sprops->os_name = copyOSName();
-    sprops->os_version = copyOSVersion();
+    sprops->os_version = strdup("Unknown");
 }