OSC: use namespaces and deletion to avoid conflicts over LocationMarker type

note that this type is also declared by the GTK2 GUI, and at runtime that was the definition being
used, which leads to crashes due to differences in the type definition.

libs/surfaces/osc/osc.cc

@@ -3181,20 +3181,6 @@ OSC::mixer_scene_state (lo_address addr, bool zero_it)
 	return 0;
 }
 
-// two structs to help with going to markers
-struct LocationMarker {
-	LocationMarker (const std::string& l, samplepos_t w)
-		: label (l), when (w) {}
-	std::string label;
-	samplepos_t  when;
-};
-
-struct LocationMarkerSort {
-	bool operator() (const LocationMarker& a, const LocationMarker& b) {
-		return (a.when < b.when);
-	}
-};
-
 int
 OSC::set_marker (const char* types, lo_arg **argv, int argc, lo_message msg)
 {
@@ -3202,6 +3188,7 @@ OSC::set_marker (const char* types, lo_arg **argv, int argc, lo_message msg)
 		PBD::warning << "Wrong number of parameters, one only." << endmsg;
 		return -1;
 	}
+
 	const Locations::LocationList& ll (session->locations ()->list ());
 	uint32_t marker = 0;
 
@@ -3237,15 +3224,15 @@ OSC::set_marker (const char* types, lo_arg **argv, int argc, lo_message msg)
 			return -1;
 			break;
 	}
-	std::vector<LocationMarker> lm;
+	std::vector<ArdourSurface::LocationMarker> lm;
 	// get Locations that are marks
 	for (Locations::LocationList::const_iterator l = ll.begin(); l != ll.end(); ++l) {
 		if ((*l)->is_mark ()) {
-			lm.push_back (LocationMarker((*l)->name(), (*l)->start_sample ()));
+			lm.push_back (ArdourSurface::LocationMarker((*l)->name(), (*l)->start_sample ()));
 		}
 	}
 	// sort them by position
-	LocationMarkerSort location_marker_sort;
+	ArdourSurface::LocationMarkerSort location_marker_sort;
 	std::sort (lm.begin(), lm.end(), location_marker_sort);
 	// go there
 	if (marker < lm.size()) {

libs/surfaces/osc/osc.h

@@ -51,7 +51,6 @@
 
 class OSCControllable;
 class OSCRouteObserver;
-class OSCGlobalObserver;
 class OSCSelectObserver;
 class OSCCueObserver;
 
@@ -68,6 +67,8 @@ class ZeroConf;
 
 namespace ArdourSurface {
 
+class OSCGlobalObserver;
+
 struct OSCUIRequest : public BaseUI::BaseRequestObject {
   public:
 	OSCUIRequest () {}

libs/surfaces/osc/osc_global_observer.h

@@ -34,6 +34,22 @@
 #include "ardour/session.h"
 #include "ardour/types.h"
 
+namespace ArdourSurface {
+
+
+struct LocationMarker {
+	LocationMarker (const std::string& l, samplepos_t w)
+		: label (l), when (w) {}
+	std::string label;
+	samplepos_t  when;
+};
+
+struct LocationMarkerSort {
+	bool operator() (const LocationMarker& a, const LocationMarker& b) {
+		return (a.when < b.when);
+	}
+};
+
 class OSCGlobalObserver
 {
 
@@ -47,6 +63,8 @@ class OSCGlobalObserver
 	void jog_mode (uint32_t jogmode);
 
   private:
+	friend ArdourSurface::OSC;
+
 	ArdourSurface::OSC& _osc;
 
 	PBD::ScopedConnectionList strip_connections;
@@ -79,20 +97,8 @@ class OSCGlobalObserver
 	uint32_t last_click;
 	samplepos_t prev_mark;
 	samplepos_t next_mark;
-	struct LocationMarker {
-		LocationMarker (const std::string& l, samplepos_t w)
-			: label (l), when (w) {}
-		std::string label;
-		samplepos_t  when;
-	};
 	std::vector<LocationMarker> lm;
 
-	struct LocationMarkerSort {
-		bool operator() (const LocationMarker& a, const LocationMarker& b) {
-			return (a.when < b.when);
-		}
-	};
-
 	void update_mixer_scene_state();
 	void send_change_message (std::string path, std::shared_ptr<PBD::Controllable> controllable);
 	void send_gain_message (std::string path, std::shared_ptr<PBD::Controllable> controllable);
@@ -108,4 +114,6 @@ class OSCGlobalObserver
 	void group_changed (void);
 };
 
+} /* namespace */
+
 #endif /* __osc_oscglobalobserver_h__ */