Implement hotloading

* This commit implements dltools.{c,h}: _A simple wrapper around libdl / dlfcn.h_
* Reload states when done initializing engine, if hotloading is enabled.
* Adds general function types for state functions.

2 files changed, 17 insertions, 0 deletions

diff --git a/include/engine/dltools.h b/include/engine/dltools.h
new file mode 100644
index 0000000..9306ae7
--- /dev/null
+++ b/include/engine/dltools.h
@@ -0,0 +1,14 @@
+#ifndef DLTOOLS_H
+#define DLTOOLS_H
+
+/* Utility functions for handling runtime linked shared libraries */
+bool dynamic_library_close(void* shared_library);
+void* dynamic_library_open(const char *library_path);
+void* dynamic_library_reload(void* shared_library, const char *library_path);
+
+/* Returns the address of symbol in the provided shared_library handle.
+ * NULL on error*/
+void* dynamic_library_get_symbol(void* shared_library, const char *symbol);
+char* dynamic_library_get_error(void);
+
+#endif
diff --git a/include/engine/state.h b/include/engine/state.h
index 402c701..cf486cc 100644
--- a/include/engine/state.h
+++ b/include/engine/state.h
@@ -20,4 +20,7 @@ void State_init(StateType type,   memory *mem);
 void State_free(StateType type,   memory *mem);
 StateType State_update(StateType type, memory *mem);
 
+/* Reloads shared object file associated with state */
+bool State_reload(StateType type);
+
 #endif