add -binary option to read raw binary files without header

.gitignore

@@ -14,6 +14,7 @@
 *.asm
 *.o
 *.dbg
+*.bin
 *.nes
 .testCoverage
 nesgodisasm

README.md

@@ -90,23 +90,25 @@ ld65 example.o -t nes -o example.nes
 usage: nesgodisasm [options] <file to disassemble>
 
   -a string
-    	Assembler compatibility of the generated .asm file (asm6/ca65/nesasm) (default "ca65")
+        Assembler compatibility of the generated .asm file (asm6/ca65/nesasm) (default "ca65")
   -batch string
-    	process a batch of given path and file mask and automatically .asm file naming, for example *.nes
+        process a batch of given path and file mask and automatically .asm file naming, for example *.nes
+  -binary
+        read input file as raw binary file without any header
   -c string
-    	Config file name to write output to for ca65 assembler
+        Config file name to write output to for ca65 assembler
   -cdl string
-    	name of the .cdl Code/Data log file to load
+        name of the .cdl Code/Data log file to load
   -debug
-    	enable debugging options for extended logging
+        enable debugging options for extended logging
   -nohexcomments
-    	do not output opcode bytes as hex values in comments
+        do not output opcode bytes as hex values in comments
   -nooffsets
-    	do not output offsets in comments
+        do not output offsets in comments
   -o string
-    	name of the output .asm file, printed on console if no name given
-  -q	perform operations quietly
+        name of the output .asm file, printed on console if no name given
+  -q    perform operations quietly
   -verify
-    	verify the generated output by assembling with ca65 and check if it matches the input
-  -z	output the trailing zero bytes of banks
+        verify the generated output by assembling with ca65 and check if it matches the input
+  -z    output the trailing zero bytes of banks
 ```

go.mod

@@ -2,4 +2,4 @@ module github.com/retroenv/nesgodisasm
 
 go 1.22
 
-require github.com/retroenv/retrogolib v0.0.0-20240429170148-9ce0db22ccb0
+require github.com/retroenv/retrogolib v0.0.0-20241105003543-931e147416dc

go.sum

@@ -1,4 +1,2 @@
-github.com/retroenv/retrogolib v0.0.0-20240304170601-1176bfc2fb7c h1:D9vm2K2Po+MTs0t/UdGY/hLzI8YSfwxLxpVxA5EQuaM=
-github.com/retroenv/retrogolib v0.0.0-20240304170601-1176bfc2fb7c/go.mod h1:kvmonrBF8P56SmAZwPA29fWgNEhFNHQ9cxXpy/w8Uio=
-github.com/retroenv/retrogolib v0.0.0-20240429170148-9ce0db22ccb0 h1:Yc5x58s3NvQJjsgEQ+fyleW9oAYe/vBadMB++bO8VUA=
-github.com/retroenv/retrogolib v0.0.0-20240429170148-9ce0db22ccb0/go.mod h1:HZ3Y8NA+pJQrTLDJ6VSg/X6Oo4jWxz2S9ZMSvv8Zm1o=
+github.com/retroenv/retrogolib v0.0.0-20241105003543-931e147416dc h1:hRuZBHYI/K0w0PTQEJrJ8o5hwW9s1wqWqEogdBL8Z3o=
+github.com/retroenv/retrogolib v0.0.0-20241105003543-931e147416dc/go.mod h1:8pe9mEjbKL9Z5L4FFzYGSk1Ovhrq1LR6ucwRFj5CIXs=

internal/disasm.go

@@ -207,7 +207,13 @@ func (dis *Disasm) initializeIrqHandlers() {
 		dis.handlers.NMI = "NMI"
 	}
 
-	reset := dis.readMemoryWord(irqStartAddress + 2)
+	var reset uint16
+	if dis.options.Binary {
+		reset = uint16(nes.CodeBaseAddress)
+	} else {
+		reset = dis.readMemoryWord(irqStartAddress + 2)
+	}
+
 	dis.logger.Debug("Reset handler", log.String("address", fmt.Sprintf("0x%04X", reset)))
 	offsetInfo := dis.mapper.offsetInfo(reset)
 	if offsetInfo != nil {

internal/options/options.go

@@ -16,6 +16,7 @@ type Program struct {
 	Output      string
 
 	AssembleTest bool
+	Binary       bool
 	Debug        bool
 	Quiet        bool
 
@@ -28,6 +29,7 @@ type Disassembler struct {
 	Assembler   string        // what assembler to use
 	CodeDataLog io.ReadCloser // Code/Data log file to parse
 
+	Binary         bool
 	CodeOnly       bool
 	HexComments    bool
 	OffsetComments bool

main.go

@@ -57,6 +57,7 @@ func initializeApp() (*log.Logger, *options.Program, *options.Disassembler) {
 	var zeroBytes bool
 
 	flags.StringVar(&opts.Assembler, "a", "ca65", "Assembler compatibility of the generated .asm file (asm6/ca65/nesasm)")
+	flags.BoolVar(&opts.Binary, "binary", false, "read input file as raw binary file without any header")
 	flags.StringVar(&opts.Batch, "batch", "", "process a batch of given path and file mask and automatically .asm file naming, for example *.nes")
 	flags.StringVar(&opts.Config, "c", "", "Config file name to write output to for ca65 assembler")
 	flags.BoolVar(&opts.Debug, "debug", false, "enable debugging options for extended logging")
@@ -150,7 +151,14 @@ func disasmFile(logger *log.Logger, opts *options.Program, disasmOptions *option
 		return fmt.Errorf("opening file '%s': %w", opts.Input, err)
 	}
 
-	cart, err := cartridge.LoadFile(file)
+	disasmOptions.Binary = opts.Binary
+	var cart *cartridge.Cartridge
+
+	if opts.Binary {
+		cart, err = cartridge.LoadBuffer(file)
+	} else {
+		cart, err = cartridge.LoadFile(file)
+	}
 	if err != nil {
 		return fmt.Errorf("reading file: %w", err)
 	}