set up a system to handle detection of bogus roms by header instead of by extension. fix poly sorting which was broken when changed to a stable sort (will make some invisible gui elements reappear)

desmume/src/NDSSystem.cpp

@@ -766,7 +766,7 @@ int NDS_LoadROM( const char *filename,
 	else if ( !strcasecmp(extROM, ".gba") && !strcasecmp(extROM2, ".ds")) 
 		type = ROM_DSGBA;
 	else
-		return -1;
+		type = ROM_NDS;
 
 	file = reader->Init(filename);
 	if (!file)
@@ -819,9 +819,15 @@ int NDS_LoadROM( const char *filename,
 	//decrypt if necessary..
 	//but this is untested and suspected to fail on big endian, so lets not support this on big endian
 #ifndef WORDS_BIGENDIAN
-	DecryptSecureArea(data,size);
+	bool okRom = DecryptSecureArea(data,size);
+
+	if(!okRom) {
+		printf("Specified file is not a valid rom\n");
+		return -1;
+	}
 #endif
 
+
 	MMU_unsetRom();
 	NDS_SetROM(data, mask);
 	NDS_Reset();

desmume/src/gfx3d.cpp

@@ -1412,8 +1412,9 @@ static bool gfx3d_ysort_compare(int num1, int num2)
 	const POLY &poly1 = polylist->list[num1];
 	const POLY &poly2 = polylist->list[num2];
 
-	if (poly1.maxy > poly2.maxy) return true;
-	if (poly1.maxy < poly2.maxy) return false;
+	//this may be verified by checking the game create menus in harvest moon island of happiness
+	if (poly1.maxy > poly2.maxy) return false;
+	if (poly1.maxy < poly2.maxy) return true;
 	if (poly1.miny < poly2.miny) return true;
 	if (poly1.miny > poly2.miny) return false;
 	return false;  //equal should always return false "strict weak ordering"

desmume/src/utils/decrypt/decrypt.cpp

@@ -449,7 +449,7 @@ static void decrypt_arm9(u32 cardheader_gamecode, unsigned char *data)
 }
 
 
-void DecryptSecureArea(u8 *romdata, long romlen)
+bool DecryptSecureArea(u8 *romdata, long romlen)
 {
 	//this looks like it will only work on little endian hosts
 	Header* header = (Header*)romdata;
@@ -465,6 +465,9 @@ void DecryptSecureArea(u8 *romdata, long romlen)
 	unsigned int sbox_offsets = 0x2800;
 #endif
 
+	if(romType == ROMTYPE_INVALID)
+		return false;
+
 	// check if ROM is already encrypted
 	if (romType == ROMTYPE_NDSDUMPED)
 	{
@@ -498,4 +501,6 @@ void DecryptSecureArea(u8 *romdata, long romlen)
 	{
 		printf("File doesn't appear to have a secure area.\n");
 	}
+
+	return true;
 }

desmume/src/utils/decrypt/decrypt.h

@@ -21,6 +21,6 @@
 #ifndef _DECRYPT_H_
 #define _DECRYPT_H_
 
-void DecryptSecureArea(u8 *romdata, long romlen);
+bool DecryptSecureArea(u8 *romdata, long romlen);
 
 #endif

desmume/src/utils/decrypt/header.cpp

@@ -69,6 +69,10 @@
 int DetectRomType(const Header& header, char* romdata)
 {
 	unsigned int * data = (unsigned int*)(romdata + 0x4000);
+
+	//this is attempting to check for an utterly invalid nds header
+	if(header.unitcode != 0) return ROMTYPE_INVALID;
+
 	if (header.arm9_rom_offset < 0x4000) return ROMTYPE_HOMEBREW;
 	if (data[0] == 0x00000000 && data[1] == 0x00000000) return ROMTYPE_MULTIBOOT;
 	if (data[0] == 0xE7FFDEFF && data[1] == 0xE7FFDEFF) return ROMTYPE_NDSDUMPED;

desmume/src/utils/decrypt/header.h

@@ -129,5 +129,6 @@ unsigned short CalcSecureAreaCRC(bool encrypt);
 #define ROMTYPE_NDSDUMPED	2	// decrypted secure area
 #define ROMTYPE_ENCRSECURE	3
 #define ROMTYPE_MASKROM		4	// unknown layout
+#define ROMTYPE_INVALID		5	// rejected; can't be a supported rom
 
 #endif