Refactored loader code for better error messages

src/fceu.cpp

@@ -479,10 +479,21 @@ FCEUGI *FCEUI_LoadGameVirtual(const char *name, int OverwriteVidMode, bool silen
 	//try to load each different format
 	bool FCEUXLoad(const char *name, FCEUFILE * fp);
 
-	if (iNESLoad(fullname, fp, OverwriteVidMode) ||
+	int load_result;
-		NSFLoad(fullname, fp) ||
+	load_result = iNESLoad(fullname, fp, OverwriteVidMode);
-		UNIFLoad(fullname, fp) ||
+	if (load_result == LOADER_INVALID_FORMAT)
-		FDSLoad(fullname, fp))
+	{
+		load_result = NSFLoad(fullname, fp);
+		if (load_result == LOADER_INVALID_FORMAT)
+		{
+			load_result = UNIFLoad(fullname, fp);
+			if (load_result == LOADER_INVALID_FORMAT)
+			{
+				load_result = FDSLoad(fullname, fp);
+			}
+		}
+	}	
+	if (load_result == LOADER_OK)
 	{
 
 #ifdef WIN32
@@ -559,7 +570,17 @@ FCEUGI *FCEUI_LoadGameVirtual(const char *name, int OverwriteVidMode, bool silen
 	}
 	else {
 		if (!silent)
-			FCEU_PrintError("An error occurred while loading the file.");
+		{
+			switch (load_result)
+			{
+			case LOADER_UNHANDLED_ERROR:
+				FCEU_PrintError("An error occurred while loading the file.");
+				break;
+			case LOADER_INVALID_FORMAT:
+				FCEU_PrintError("Unknown ROM file format.");
+				break;
+			}
+		}
 
 		delete GameInfo;
 		GameInfo = 0;

src/fceu.h

@@ -159,14 +159,20 @@ extern uint8 vsdip;
 
 //#define FCEUDEF_DEBUGGER //mbg merge 7/17/06 - cleaning out conditional compiles
 
-#define JOY_A   1
+#define JOY_A           0x01
-#define JOY_B   2
+#define JOY_B           0x02
-#define JOY_SELECT      4
+#define JOY_SELECT      0x04
-#define JOY_START       8
+#define JOY_START       0x08
-#define JOY_UP  0x10
+#define JOY_UP          0x10
 #define JOY_DOWN        0x20
 #define JOY_LEFT        0x40
 #define JOY_RIGHT       0x80
+
+#define LOADER_INVALID_FORMAT   0
+#define LOADER_OK               1
+#define LOADER_HANDLED_ERROR    2
+#define LOADER_UNHANDLED_ERROR  3
+
 #endif
 
 #define ARRAY_SIZE(a) (sizeof(a)/sizeof(a[0]))

src/fds.cpp

@@ -735,6 +735,7 @@ static int SubLoad(FCEUFILE *fp) {
 	uint8 header[16];
 	int x;
 
+	FCEU_fseek(fp, 0, SEEK_SET);
 	FCEU_fread(header, 16, 1, fp);
 
 	if (memcmp(header, "FDS\x1a", 4)) {
@@ -746,7 +747,7 @@ static int SubLoad(FCEUFILE *fp) {
 			TotalSides = t / 65500;
 			FCEU_fseek(fp, 0, SEEK_SET);
 		} else
-			return(0);
+			return 1;
 	} else
 		TotalSides = header[4];
 
@@ -756,18 +757,12 @@ static int SubLoad(FCEUFILE *fp) {
 	if (TotalSides < 1) TotalSides = 1;
 
 	for (x = 0; x < TotalSides; x++) {
-		diskdata[x] = (uint8*)FCEU_malloc(65500);
+		if ((diskdata[x] = (uint8*)FCEU_malloc(65500)) == NULL) return 2;
-		if (!diskdata[x]) {
-			int zol;
-			for (zol = 0; zol < x; zol++)
-				free(diskdata[zol]);
-			return 0;
-		}
 		FCEU_fread(diskdata[x], 1, 65500, fp);
 		md5_update(&md5, diskdata[x], 65500);
 	}
 	md5_finish(&md5, GameInfo->MD5.data);
-	return(1);
+	return 0;
 }
 
 static void PreSave(void) {
@@ -792,21 +787,37 @@ int FDSLoad(const char *name, FCEUFILE *fp) {
 	FILE *zp;
 	int x;
 
+	// try to load FDS image first
+	FreeFDSMemory();
+	int load_result = SubLoad(fp);
+	switch (load_result)
+	{
+	case 1:
+		FreeFDSMemory();
+		return LOADER_INVALID_FORMAT;
+	case 2:
+		FreeFDSMemory();
+		FCEU_PrintError("Unable to allocate memory.");
+		return LOADER_HANDLED_ERROR;
+	}
+
+	// load FDS BIOS next
 	char *fn = strdup(FCEU_MakeFName(FCEUMKF_FDSROM, 0, 0).c_str());
 
 	if (!(zp = FCEUD_UTF8fopen(fn, "rb"))) {
 		FCEU_PrintError("FDS BIOS ROM image missing: %s", FCEU_MakeFName(FCEUMKF_FDSROM, 0, 0).c_str());
 		free(fn);
-		return 0;
+		FreeFDSMemory();
+		return LOADER_HANDLED_ERROR;
 	}
-
 	free(fn);
 
 	fseek(zp, 0L, SEEK_END);
 	if (ftell(zp) != 8192) {
 		fclose(zp);
+		FreeFDSMemory();
 		FCEU_PrintError("FDS BIOS ROM image incompatible: %s", FCEU_MakeFName(FCEUMKF_FDSROM, 0, 0).c_str());
-		return 0;
+		return LOADER_HANDLED_ERROR;
 	}
 	fseek(zp, 0L, SEEK_SET);
 
@@ -831,22 +842,13 @@ int FDSLoad(const char *name, FCEUFILE *fp) {
 			free(FDSBIOS);
 		FDSBIOS = NULL;
 		fclose(zp);
+		FreeFDSMemory();
 		FCEU_PrintError("Error reading FDS BIOS ROM image.");
-		return 0;
+		return LOADER_HANDLED_ERROR;
 	}
 
 	fclose(zp);
 
-	FCEU_fseek(fp, 0, SEEK_SET);
-
-	FreeFDSMemory();
-	if (!SubLoad(fp)) {
-		if(FDSBIOS)
-			free(FDSBIOS);
-		FDSBIOS = NULL;
-		return(0);
-	}
-
 	if (!disableBatteryLoading) {
 		FCEUFILE *tp;
 		char *fn = strdup(FCEU_MakeFName(FCEUMKF_FDS, 0, 0).c_str());
@@ -866,7 +868,8 @@ int FDSLoad(const char *name, FCEUFILE *fp) {
 					free(FDSBIOS);
 				FDSBIOS = NULL;
 				free(fn);
-				return(0);
+				FreeFDSMemory();
+				return LOADER_HANDLED_ERROR;
 			}
 			FCEU_fclose(tp);
 			DiskWritten = 1;  /* For save state handling. */
@@ -929,7 +932,7 @@ int FDSLoad(const char *name, FCEUFILE *fp) {
 
 	FCEUI_SetVidSystem(0);
 
-	return 1;
+	return LOADER_OK;
 }
 
 void FDSClose(void) {

src/ines.cpp

@@ -737,7 +737,7 @@ int iNESLoad(const char *name, FCEUFILE *fp, int OverwriteVidMode) {
 	struct md5_context md5;
 
 	if (FCEU_fread(&head, 1, 16, fp) != 16 || memcmp(&head, "NES\x1A", 4))
-		return 0;
+		return LOADER_INVALID_FORMAT;
 	
 	head.cleanup();
 
@@ -794,7 +794,8 @@ int iNESLoad(const char *name, FCEUFILE *fp, int OverwriteVidMode) {
 		if ((VROM = (uint8*)FCEU_malloc(VROM_size << 13)) == NULL) {
 			free(ROM);
 			ROM = NULL;
-			return 0;
+			FCEU_PrintError("Unable to allocate memory.");
+			return LOADER_HANDLED_ERROR;
 		}
 		memset(VROM, 0xFF, VROM_size << 13);
 	}
@@ -902,7 +903,7 @@ int iNESLoad(const char *name, FCEUFILE *fp, int OverwriteVidMode) {
 		goto init_ok;
 	case 1:
 		FCEU_PrintError("iNES mapper #%d is not supported at all.", MapperNo);
-		goto init_ok; // this error is still allowed to run as NROM?
+		break;
 	case 2:
 		FCEU_PrintError("Unable to allocate CHR-RAM.");
 		break;
@@ -915,7 +916,8 @@ int iNESLoad(const char *name, FCEUFILE *fp, int OverwriteVidMode) {
 	VROM = NULL;
 	trainerpoo = NULL;
 	ExtraNTARAM = NULL;
-	return 0;
+	return LOADER_HANDLED_ERROR;
+
 init_ok:
 
 	GameInfo->mappernum = MapperNo;
@@ -949,7 +951,7 @@ init_ok:
 		else
 			FCEUI_SetVidSystem(0);
 	}
-	return 1;
+	return LOADER_OK;
 }
 
 // bbit edited: the whole function below was added

src/nsf.cpp

@@ -174,7 +174,7 @@ int NSFLoad(const char *name, FCEUFILE *fp)
 	FCEU_fseek(fp,0,SEEK_SET);
 	FCEU_fread(&NSFHeader,1,0x80,fp);
 	if(memcmp(NSFHeader.ID,"NESM\x1a",5))
-		return 0;
+		return LOADER_INVALID_FORMAT;
 	NSFHeader.SongName[31]=NSFHeader.Artist[31]=NSFHeader.Copyright[31]=0;
 
 	LoadAddr=NSFHeader.LoadAddressLow;
@@ -183,7 +183,7 @@ int NSFLoad(const char *name, FCEUFILE *fp)
 	if(LoadAddr<0x6000)
 	{
 		FCEUD_PrintError("Invalid load address.");
-		return(0);
+		return LOADER_HANDLED_ERROR;
 	}
 	InitAddr=NSFHeader.InitAddressLow;
 	InitAddr|=NSFHeader.InitAddressHigh<<8;
@@ -196,8 +196,11 @@ int NSFLoad(const char *name, FCEUFILE *fp)
 	NSFMaxBank=((NSFSize+(LoadAddr&0xfff)+4095)/4096);
 	NSFMaxBank=PRGsize[0]=uppow2(NSFMaxBank);
 
-	if(!(NSFDATA=(uint8 *)FCEU_malloc(NSFMaxBank*4096)))
+	if (!(NSFDATA = (uint8 *)FCEU_malloc(NSFMaxBank * 4096)))
-		return 0;
+	{
+		FCEU_PrintError("Unable to allocate memory.");
+		return LOADER_HANDLED_ERROR;
+	}
 
 	FCEU_fseek(fp,0x80,SEEK_SET);
 	memset(NSFDATA,0x00,NSFMaxBank*4096);
@@ -288,7 +291,7 @@ int NSFLoad(const char *name, FCEUFILE *fp)
 
 	FCEUI_SetVidSystem(NSFHeader.VideoSystem);
 
-	return 1;
+	return LOADER_OK;
 }
 
 static DECLFR(NSFVectorRead)

src/unif.cpp

@@ -544,18 +544,17 @@ static int InitializeBoard(void) {
 					SetupCartCHRMapping(0, UNIFchrrama, CHRRAMSize, 1);
 					AddExState(UNIFchrrama, CHRRAMSize, 0, "CHRR");
 				} else
-					return(-1);
+					return 2;
 			}
 			if (bmap[x].flags & BMCFLAG_FORCE4)
 				mirrortodo = 4;
 			MooMirroring();
 			bmap[x].init(&UNIFCart);
-			return(1);
+			return 0;
 		}
 		x++;
 	}
-	FCEU_PrintError("Board type not supported.");
+	return 1;
-	return(0);
 }
 
 static void UNIFGI(GI h) {
@@ -586,51 +585,56 @@ int UNIFLoad(const char *name, FCEUFILE *fp) {
 	FCEU_fseek(fp, 0, SEEK_SET);
 	FCEU_fread(&unhead, 1, 4, fp);
 	if (memcmp(&unhead, "UNIF", 4))
-		return 0;
+		return LOADER_INVALID_FORMAT;
 
 	ResetCartMapping();
 
 	ResetExState(0, 0);
 	ResetUNIF();
-	if (!FCEU_read32le(&unhead.info, fp))
+	if (!FCEU_read32le(&unhead.info, fp)
-		goto aborto;
+		|| (FCEU_fseek(fp, 0x20, SEEK_SET) < 0)
-	if (FCEU_fseek(fp, 0x20, SEEK_SET) < 0)
+		|| !LoadUNIFChunks(fp))
-		goto aborto;
-	if (!LoadUNIFChunks(fp))
-		goto aborto;
 	{
-		int x;
+		FreeUNIF();
-		struct md5_context md5;
+		ResetUNIF();
-
+		FCEU_PrintError("Error reading UNIF ROM image.");
-		md5_starts(&md5);
+		return LOADER_HANDLED_ERROR;
-
-		for (x = 0; x < 32; x++)
-			if (malloced[x]) {
-				md5_update(&md5, malloced[x], mallocedsizes[x]);
-			}
-		md5_finish(&md5, UNIFCart.MD5);
-		FCEU_printf(" ROM MD5:  0x");
-		for (x = 0; x < 16; x++)
-			FCEU_printf("%02x", UNIFCart.MD5[x]);
-		FCEU_printf("\n");
-		memcpy(&GameInfo->MD5, &UNIFCart.MD5, sizeof(UNIFCart.MD5));
 	}
 
-	if (!InitializeBoard())
+	struct md5_context md5;
-		goto aborto;
+	md5_starts(&md5);
+	for (int x = 0; x < 32; x++)
+		if (malloced[x]) {
+			md5_update(&md5, malloced[x], mallocedsizes[x]);
+		}
+	md5_finish(&md5, UNIFCart.MD5);
+	FCEU_printf(" ROM MD5:  0x");
+	for (int x = 0; x < 16; x++)
+		FCEU_printf("%02x", UNIFCart.MD5[x]);
+	FCEU_printf("\n");
+	memcpy(&GameInfo->MD5, &UNIFCart.MD5, sizeof(UNIFCart.MD5));
+
+	int result = InitializeBoard();
+	switch (result)
+	{
+	case 0:
+		goto init_ok;
+	case 1:
+		FCEU_PrintError("UNIF mapper \"%s\" is not supported at all.", sboardname);
+		break;
+	case 2:
+		FCEU_PrintError("Unable to allocate CHR-RAM.");
+		break;
+	}
+	FreeUNIF();
+	ResetUNIF();
+	return LOADER_HANDLED_ERROR;
+
+init_ok:
 
 	FCEU_LoadGameSave(&UNIFCart);
-
 	strcpy(LoadedRomFName, name); //For the debugger list
 	GameInterface = UNIFGI;
 	currCartInfo = &UNIFCart;
-	return 1;
+	return LOADER_OK;
-
- aborto:
-
-	FreeUNIF();
-	ResetUNIF();
-
-
-	return 0;
 }