--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/system.h	Mon Dec 19 13:28:18 2016 -0800
@@ -0,0 +1,49 @@
+#ifndef SYSTEM_H_
+#define SYSTEM_H_
+#include <stdint.h>
+#include "arena.h"
+#include "romdb.h"
+
+typedef struct system_header system_header;
+
+typedef enum {
+	SYSTEM_UNKNOWN,
+	SYSTEM_GENESIS,
+	SYSTEM_SMS,
+	SYSTEM_JAGUAR
+} system_type;
+
+typedef enum {
+	DEBUGGER_NATIVE,
+	DEBUGGER_GDB
+} debugger_type;
+
+typedef void (*system_fun)(system_header *);
+typedef void (*start_system_fun)(system_header *, char *);
+typedef void (*speed_system_fun)(system_header *, uint32_t);
+
+struct system_header {
+	system_header     *next_context;
+	start_system_fun  start_context;
+	system_fun        resume_context;
+	system_fun        load_save;
+	system_fun        persist_save;
+	system_fun        request_exit;
+	system_fun        free_context;
+	speed_system_fun  set_speed_percent;
+	system_fun        inc_debug_mode;
+	system_fun        inc_debug_pal;
+	arena             *arena;
+	char              *next_rom;
+	char              *save_dir;
+	uint8_t           enter_debugger;
+	uint8_t           should_exit;
+	uint8_t           save_state;
+	debugger_type     debugger_type;
+	system_type       type;
+};
+
+system_type detect_system_type(uint8_t *rom, long filesize);
+system_header *alloc_config_system(system_type stype, void *rom, uint32_t rom_size, void *lock_on, uint32_t lock_on_size, uint32_t opts, uint8_t force_region, rom_info *info_out);
+
+#endif //SYSTEM_H_