Decomped unk_02018380

include/unk_02018380.h

@@ -3,8 +3,17 @@
 
 #include "igt.h"
 
+typedef struct UnkStruct_021D10E8 {
+    u32 unk0;
+    IGT *igt;
+    u64 unk8;
+    u32 unk10;
+    u32 unk14;
+    u64 unk18;
+} UnkStruct_021D10E8;
+
 void sub_02018380(void);
 void sub_020183B0(void);
-void sub_0201838C(IGT* igt);
+void sub_0201838C(IGT *igt);
 
 #endif //POKEHEARTGOLD_UNK_02018380_H

main.lsf

@@ -57,7 +57,7 @@ Static main
 	Object asm/unk_02016EDC.o
 	Object asm/unk_02017FAC.o
 	Object asm/unk_02018000.o
-	Object asm/unk_02018380.o
+	Object src/unk_02018380.o
 	Object asm/unk_020183F0.o
 	Object src/camera_translation.o
 	Object asm/unk_020192D0.o

src/unk_02018380.c

@@ -0,0 +1,33 @@
+#include "global.h"
+#include "unk_02018380.h"
+#include "timer_3.h"
+
+static UnkStruct_021D10E8 s_021D10E8;
+
+void sub_02018380(void) {
+    s_021D10E8.unk0 = 0;
+}
+
+void sub_0201838C(IGT *igt) {
+    s_021D10E8.unk0 = 1;
+    s_021D10E8.unk10 = 0;
+    s_021D10E8.unk14 = 0;
+    s_021D10E8.unk8 = 0;
+    s_021D10E8.igt = igt;
+    s_021D10E8.unk18 = sub_020254FC();
+}
+
+void sub_020183B0(void) {
+    if (s_021D10E8.unk0 == 0) {
+        return;
+    }
+
+    u64 val = sub_020254FC();
+    u64 val2 = sub_02025504(val - s_021D10E8.unk18);
+    if (s_021D10E8.unk8 >= val2) {
+        return;
+    }
+
+    AddIGTSeconds(s_021D10E8.igt, val2 - s_021D10E8.unk8);
+    s_021D10E8.unk8 = val2;
+}