From a4ef4b6092ab181c2f700c9d18498061835242cc Mon Sep 17 00:00:00 2001
From: sorgelig <pour.garbage@gmail.com>
Date: Mon, 1 Jun 2020 08:55:27 +0800
Subject: [PATCH] megacd: support per-game cd_bios.rom and cart.rom

---
 support/megacd/megacd.cpp  | 53 ++++++++++++++++++++++++++++----------
 support/megacd/megacdd.cpp | 19 ++------------
 2 files changed, 42 insertions(+), 30 deletions(-)

diff --git a/support/megacd/megacd.cpp b/support/megacd/megacd.cpp
index 45aced8..3a020de 100644
--- a/support/megacd/megacd.cpp
+++ b/support/megacd/megacd.cpp
@@ -8,11 +8,12 @@
 #include "../../user_io.h"
 #include "../../spi.h"
 #include "../../hardware.h"
+#include "../../menu.h"
 #include "megacd.h"
 
 #define SAVE_IO_INDEX 5 // fake download to trigger save loading
 
-static int loaded = 0, unloaded = 0, need_reset=0;
+static int need_reset=0;
 static uint8_t has_command = 0;
 
 void mcd_poll()
@@ -71,37 +72,63 @@ void mcd_poll()
 		DisableIO();
 }
 
+static char buf[1024];
 static void mcd_mount_save(const char *filename)
 {
 	user_io_set_index(SAVE_IO_INDEX);
 	user_io_set_download(1);
-
-	static char name[1024];
-	FileGenerateSavePath(filename, name);
-	user_io_file_mount(name, 0, 1);
-
+	if (strlen(filename))
+	{
+		FileGenerateSavePath(filename, buf);
+		user_io_file_mount(buf, 0, 1);
+	}
+	else
+	{
+		user_io_file_mount("");
+	}
 	user_io_set_download(0);
 }
 
+static int mcd_load_rom(const char *basename, const char *name, int sub_index)
+{
+	strcpy(buf, basename);
+	char *p = strrchr(buf, '/');
+	if (p)
+	{
+		p++;
+		strcpy(p, name);
+		if (user_io_file_tx(buf, sub_index << 6)) return 1;
+	}
+
+	return 0;
+}
+
 void mcd_set_image(int num, const char *filename)
 {
 	(void)num;
 
 	cdd.Unload();
-	unloaded = 1;
 	cdd.status = CD_STAT_OPEN;
 
-	if (*filename) {
+	mcd_mount_save("");
+	sprintf(buf, "%s/boot.rom", HomeDir());
+	int loaded = user_io_file_tx(buf);
+	if (!loaded) Info("CD BIOS not found!", 4000);
 
-		mcd_mount_save(filename);
-
-		if (cdd.Load(filename) > 0) {
-			loaded = 1;
+	if (loaded && *filename)
+	{
+		if (cdd.Load(filename) > 0)
+		{
 			cdd.status = cdd.loaded ? CD_STAT_STOP : CD_STAT_NO_DISC;
 			cdd.latency = 10;
 			cdd.SendData = mcd_send_data;
+
+			mcd_load_rom(filename, "cd_bios.rom", 0);
+			mcd_load_rom(filename, "cart.rom", 1);
+			mcd_mount_save(filename);
 		}
-		else {
+		else
+		{
 			cdd.status = CD_STAT_NO_DISC;
 		}
 	}
diff --git a/support/megacd/megacdd.cpp b/support/megacd/megacdd.cpp
index ad01eff..3d97f4b 100644
--- a/support/megacd/megacdd.cpp
+++ b/support/megacd/megacdd.cpp
@@ -235,7 +235,7 @@ int cdd_t::LoadCUE(const char* filename) {
 int cdd_t::Load(const char *filename)
 {
 	//char fname[1024 + 10];
-	static char header[1024];
+	static char header[32];
 	fileTYPE *fd_img;
 
 	Unload();
@@ -255,22 +255,7 @@ int cdd_t::Load(const char *filename)
 	}
 	else
 	{
-		FileReadAdv(fd_img, header, 0x10);
-		if (!memcmp("SEGADISCSYSTEM", header, 14))
-		{
-			this->sectorSize = 2352;
-		}
-	}
-
-	if (this->sectorSize)
-	{
-		FileReadAdv(fd_img, header + 0x10, 0x200);
-		FileSeek(fd_img, 0, SEEK_SET);
-	}
-	else
-	{
-		FileClose(fd_img);
-		return (-1);
+		this->sectorSize = 2352;
 	}
 
 	printf("\x1b[32mMCD: Sector size = %u, Track 0 end = %u\n\x1b[0m", this->sectorSize, this->toc.tracks[0].end);