From 2a5c3a351eeb1772306567969fb8dc5b31eaf34e Mon Sep 17 00:00:00 2001
From: fgsfds <derp.primus@gmail.com>
Date: Mon, 2 Sep 2024 10:48:54 +0200
Subject: [PATCH] port: refactor gbcRomCheck a bit

---
 port/include/romdata.h |  2 +-
 port/src/main.c        |  3 ++-
 port/src/romdata.c     | 53 +++++++++++++++++++++++-------------------
 src/game/pak.c         |  4 ++--
 src/include/bss.h      |  2 +-
 5 files changed, 35 insertions(+), 29 deletions(-)

diff --git a/port/include/romdata.h b/port/include/romdata.h
index d72c411ed..07e83ee4e 100644
--- a/port/include/romdata.h
+++ b/port/include/romdata.h
@@ -22,6 +22,6 @@ u8 *romdataSegGetData(const char *segName);
 u8 *romdataSegGetDataEnd(const char *segName);
 u32 romdataSegGetSize(const char *segName);
 
-void gbcRomCheck(void);
+s32 romdataCheckGbcRom(void);
 
 #endif
diff --git a/port/src/main.c b/port/src/main.c
index fb225e6f6..5e404426d 100644
--- a/port/src/main.c
+++ b/port/src/main.c
@@ -107,7 +107,8 @@ int main(int argc, const char **argv)
 	inputInit();
 	audioInit();
 	romdataInit();
-	gbcRomCheck();
+
+	g_ValidGbcRomFound = romdataCheckGbcRom();
 
 	gameInit();
 
diff --git a/port/src/romdata.c b/port/src/romdata.c
index 20fc55557..ade6a0f77 100644
--- a/port/src/romdata.c
+++ b/port/src/romdata.c
@@ -11,9 +11,6 @@
 #include "system.h"
 #include "preprocess.h"
 #include "platform.h"
-#ifndef PLATFORM_N64
-#include "bss.h"
-#endif
 
 /**
  * asset files and ROM segments can be replaced by optional external files,
@@ -392,43 +389,51 @@ s32 romdataInit(void)
 	return 0;
 }
 
-void gbcRomCheck(void)
+static inline bool romdataCheckGbcRomContents(const u8 *gbcRomFile, const u32 gbcRomSize)
 {
-	u32 gbcRomSize;
-	u8* gbcRomFile = fsFileLoad(GBC_ROM_NAME, &gbcRomSize);
-
-	if (!gbcRomFile) {
-		return;
-	}
-
 	if (gbcRomSize != GBC_ROM_SIZE) {
-		free(gbcRomFile);
-		return;
+		return false;
 	}
 
 	// ROM title
-
 	if (memcmp(gbcRomFile + 0x134, "PerfDark   VPDE", 15) != 0) {
-		free(gbcRomFile);
-		return;
+		return false;
 	}
 
 	// Licensee code
-
 	if (memcmp(gbcRomFile + 0x144, "4Y", 2) != 0) {
-		free(gbcRomFile);
-		return;
+		return false;
 	}
 
 	// Header and global checksums
-
 	if (gbcRomFile[0x14D] != 0xA1 || gbcRomFile[0x14E] != 0xAD || gbcRomFile[0x14F] != 0x0F) {
-		free(gbcRomFile);
-		return;
+		return false;
 	}
 
-	g_validGbcRomFound = true;
-	free(gbcRomFile);
+	return true;
+}
+
+s32 romdataCheckGbcRom(void)
+{
+	if (fsFileSize(GBC_ROM_NAME) < 0) {
+		// bail early if it doesn't exist to avoid generating error messages
+		return false;
+	}
+
+	u32 gbcRomSize = 0;
+	u8 *gbcRomFile = fsFileLoad(GBC_ROM_NAME, &gbcRomSize);
+	if (!gbcRomFile) {
+		return false;
+	}
+
+	const bool ret = romdataCheckGbcRomContents(gbcRomFile, gbcRomSize);
+	sysMemFree(gbcRomFile);
+
+	if (ret) {
+		sysLogPrintf(LOG_NOTE, "romdataCheckGbcRom: valid GBC rom found");
+	}
+
+	return ret;
 }
 
 s32 romdataFileGetSize(s32 fileNum)
diff --git a/src/game/pak.c b/src/game/pak.c
index 09c2fef7d..5747f74ee 100644
--- a/src/game/pak.c
+++ b/src/game/pak.c
@@ -330,7 +330,7 @@ bool var80075d14 = true;
 #endif
 
 #ifndef PLATFORM_N64
-bool g_validGbcRomFound = false;
+bool g_ValidGbcRomFound = false;
 #endif
 
 u32 pakGetBlockSize(s8 device)
@@ -5997,7 +5997,7 @@ bool gbpakIsAnyPerfectDark(void)
 
 	return false;
 #else
-	return g_validGbcRomFound;
+	return g_ValidGbcRomFound;
 #endif
 }
 
diff --git a/src/include/bss.h b/src/include/bss.h
index a322a9a50..a5046aa05 100644
--- a/src/include/bss.h
+++ b/src/include/bss.h
@@ -294,7 +294,7 @@ extern struct chrdata *g_MpBotChrPtrs[MAX_BOTS];
 extern s32 g_JpnMaxCacheItems;
 extern s32 var8009d370jf;
 #ifndef PLATFORM_N64
-extern bool g_validGbcRomFound;
+extern bool g_ValidGbcRomFound;
 #endif
 
 #endif