ocarina: Load images using the full path

relative paths can't be trusted once the program has been installed.  To
get around this, I assume that the install directory has been configured
correctly and then point to images located in the subdirectory next to
the executable.

include/ocarina/ocarina.h

@@ -6,6 +6,7 @@ namespace ocarina
 
 	void quit();
 	void idle_add();
+	string full_path(string);
 
 };
 

ocarina/buttons/toggle.cpp

@@ -1,6 +1,7 @@
 
 #include <ocarina/gtk.h>
 #include <ocarina/button.h>
+#include <ocarina/ocarina.h>
 #include <libsaria/prefs.h>
 
 static GtkWidget *get_toggle_button(void (* func)(GtkWidget *, GdkEvent *, gpointer),
@@ -41,7 +42,7 @@ static void toggle_random(GtkWidget *b, GdkEvent *e, gpointer d)
 
 GtkWidget *make_random_button()
 {
-	return make_toggle_button("images/random.png",
+	return make_toggle_button(ocarina::full_path("images/random.png"),
 				  toggle_random,
 				  libsaria::prefs::get_bool("random"),
 				  true);

ocarina/ocarina.cpp

@@ -12,6 +12,22 @@
 #include <libsaria/print.h>
 #include <libsaria/idle.h>
 
+static string path_prefix;
+
+void set_path_prefix(string prefix)
+{
+	unsigned int stop = 0;
+
+	for (stop = prefix.size() - 1; stop > 0; stop--) {
+		if (prefix[stop] == '/')
+			break;
+	}
+
+	for (unsigned int i = 0; i < stop; i++)
+		path_prefix += prefix[i];
+	println("Path prefix: " + path_prefix);
+}
+
 namespace ocarina
 {
 
@@ -27,9 +43,16 @@ namespace ocarina
 		g_idle_add(idle, NULL);
 	}
 
+	string full_path(string path)
+	{
+		string res = path_prefix + "/" + path;
+		println("Expanding to path: " + res);
+		return res;
+	}
+
 	void init(int argc, char **argv)
 	{
-		window_init("Ocarina " + vers_str(), "images/ocarina.png");
+		window_init("Ocarina " + vers_str(), full_path("images/ocarina.png"));
 		window_add(get_tabs());
 		ocarina::library::init();
 		settings_init();
@@ -45,6 +68,7 @@ namespace ocarina
 int main(int argc, char **argv)
 {
 	println("Ocarina " + vers_str());
+	set_path_prefix(argv[0]);
 
 	libsaria::init(argc, argv);
 	setup_callbacks();