From a3bc614e68d772048b1bb9dd56b4a0d813dd0fe9 Mon Sep 17 00:00:00 2001
From: nmlgc <nmlgc@nmlgc.net>
Date: Wed, 10 Aug 2022 17:04:08 +0200
Subject: [PATCH] [Decompilation] [th01] MDRV2: Move all data to C land

Part of P0213, funded by Ember2528 and GhostRiderCog.
---
 th01/snd/mdrv2.cpp       | 25 +++++++++++++++----------
 th01/snd/mdrv2[data].asm |  5 -----
 th01_fuuin_data.asm      |  1 -
 th01_op.asm              |  1 -
 th01_reiiden.asm         |  1 -
 5 files changed, 15 insertions(+), 18 deletions(-)
 delete mode 100644 th01/snd/mdrv2[data].asm

diff --git a/th01/snd/mdrv2.cpp b/th01/snd/mdrv2.cpp
index 85b68df5..559449f7 100644
--- a/th01/snd/mdrv2.cpp
+++ b/th01/snd/mdrv2.cpp
@@ -15,6 +15,8 @@ extern "C" {
 #include "th01/snd/mdrv2.h"
 }
 
+#define MDRV2_MAGIC "Mdrv2System"
+
 typedef enum {
 	MDRV2_MPLAY = 0x00,
 	MDRV2_MFADE_OUT_BLOCK = 0x01,
@@ -29,29 +31,32 @@ typedef enum {
 
 static const uint8_t MDRV2 = 0xF2;
 
+inline int16_t mdrv2_segment(void) {
+	// 0000:((0xF2 * 4) + 2)
+	return peek(0, ((MDRV2 * sizeof(void far *)) + sizeof(void near *)));
+}
+
 inline uint16_t mdrv2_call(mdrv2_func_t func) {
 	_AH = func;
 	geninterrupt(MDRV2);
 	return _AX;
 }
 
-extern char mdrv2_have_board;
-struct hack { char x[12]; }; // XXX
-extern const struct hack mdrv2_magic;
+static int8_t mdrv2_have_board = false; // ACTUAL TYPE: bool
+static int8_t mdrv2_unused = 0; // ZUN bloat
 
 bool16 mdrv2_resident(void)
 {
-	char s1[sizeof(mdrv2_magic)];
-	const struct hack s2 = mdrv2_magic;
-	char far *magicp = (char far *)(
-		((long)peek(0, MDRV2 * 4 + 2) << 16) + 0x102
+	char s1[sizeof(MDRV2_MAGIC)];
+	const char MAGIC[] = "Mdrv2System";
+	char far *magicp = reinterpret_cast<char far *>(
+		(static_cast<uint32_t>(mdrv2_segment()) << 16) + 0x102
 	);
-	int i;
 
-	for(i = 0; i < sizeof(s1); i++) {
+	for(int i = 0; i < sizeof(s1); i++) {
 		s1[i] = magicp[i];
 	}
-	if(strcmp(s1, s2.x) != 0) {
+	if(strcmp(s1, MAGIC) != 0) {
 		return false;
 	}
 	return true;
diff --git a/th01/snd/mdrv2[data].asm b/th01/snd/mdrv2[data].asm
deleted file mode 100644
index 9b8d64b9..00000000
--- a/th01/snd/mdrv2[data].asm
+++ /dev/null
@@ -1,5 +0,0 @@
-public _mdrv2_have_board
-_mdrv2_have_board	db 0
-		db 0
-public _mdrv2_magic
-_mdrv2_magic	db 'Mdrv2System',0
diff --git a/th01_fuuin_data.asm b/th01_fuuin_data.asm
index ebc9779f..be5a236a 100644
--- a/th01_fuuin_data.asm
+++ b/th01_fuuin_data.asm
@@ -16,6 +16,5 @@ include th01/hardware/palette[data].asm
 include th01/hardware/graph_r[data].asm
 include th01/hardware/respal[data].asm
 include th01/formats/grp_ptn[data].asm
-include th01/snd/mdrv2[data].asm
 
 	end
diff --git a/th01_op.asm b/th01_op.asm
index 0741c8e2..6bfa2f31 100644
--- a/th01_op.asm
+++ b/th01_op.asm
@@ -1612,7 +1612,6 @@ include libs/master.lib/clip[data].asm
 include libs/master.lib/rand[data].asm
 public _res_id
 _res_id	db 'ReiidenConfig',0
-include th01/snd/mdrv2[data].asm
 	.data?
 
 public _rand
diff --git a/th01_reiiden.asm b/th01_reiiden.asm
index ac7c47ec..455c2559 100644
--- a/th01_reiiden.asm
+++ b/th01_reiiden.asm
@@ -3343,7 +3343,6 @@ include th01/sprites/ileave_m.asp
 		db    0
 		db 0FFh
 include th01/sprites/laser_s.asp
-include th01/snd/mdrv2[data].asm
 
 	extern _arc_key:byte
 	extern _card_flip_cycle:byte