Remove unnecessary platform specific workaround in iso9660util

[arixmkii]

I've been experimenting using latest Lima with QEMU on Windows and during my initial tests writing .iso file would always result in app panicking inside the third party library (I don't have stack trace preserved unfortunately). By removing this transformation of path I did manage to get a running setup. Probably the native Windows path handling was added in upstream, but I didn't try to bisect there no evidence when it was last working.

cc: @afbjorklund tagging you, because you added this part some time ago f264c90

[afbjorklund]

If it works now, it was probably fixed in either the go-diskfs or in go. Back then, it didn't like when mixing them.

• Embed does not respect Windows filepaths golang/go#44305

[afbjorklund]

But from what I can tell, it still seems to be using path.Join (not filepath.Join), so surprised that it works...

https://github.com/diskfs/go-diskfs/tree/master/filesystem/iso9660

                fullPath := path.Join(fsm.workspace, p)

[arixmkii]

I'll rebuild from unaltered to double check and post stack trace here later.

[arixmkii]

It is definitely using filepath to walk the tree https://github.com/diskfs/go-diskfs/blob/5fa33cdab5b6560db5cd07ad9a9177bd12e6abc6/filesystem/iso9660/finalize.go#L917C9-L917C17

Same in the master HEAD.

[arixmkii]

And here is stack trace showing filepath being used, where it panics

panic: runtime error: invalid memory address or nil pointer dereference
[signal 0xc0000005 code=0x0 addr=0xf8 pc=0x14e7e6b]

goroutine 1 [running]:
github.com/diskfs/go-diskfs/filesystem/iso9660.walkTree.func1({0xc00032b9c0, 0x3b}, {0x1dfd718, 0xc00031a1c0}, {0x0?, 0x0?})
	C:/Users/User/go/pkg/mod/github.com/diskfs/[email protected]/filesystem/iso9660/finalize.go:948 +0x40b
path/filepath.walkDir({0xc00032b9c0, 0x3b}, {0x1dfd718, 0xc00031a1c0}, 0xc00013ece8)
	C:/msys64/ucrt64/lib/go/src/path/filepath/path.go:310 +0x50
path/filepath.walkDir({0xc000398680, 0x36}, {0x1dfd750, 0xc000308020}, 0xc00013ece8)
	C:/msys64/ucrt64/lib/go/src/path/filepath/path.go:332 +0x285
path/filepath.WalkDir({0xc000398680, 0x36}, 0xc00013ece8)
	C:/msys64/ucrt64/lib/go/src/path/filepath/path.go:400 +0x75
github.com/diskfs/go-diskfs/filesystem/iso9660.walkTree({0xc000398680, 0x36})
	C:/Users/User/go/pkg/mod/github.com/diskfs/[email protected]/filesystem/iso9660/finalize.go:917 +0xc5
github.com/diskfs/go-diskfs/filesystem/iso9660.(*FileSystem).Finalize(0xc000678900, {0x0?, 0x89?, 0x0?, {0x1bbfae4?, 0x1ded320?}})
	C:/Users/User/go/pkg/mod/github.com/diskfs/[email protected]/filesystem/iso9660/finalize.go:480 +0x29d
github.com/lima-vm/lima/pkg/iso9660util.Write({0xc0003985c0, 0x27}, {0x1bbfae4, 0x6}, {0xc0003b8d88, 0x1f, 0x7?})
	C:/msys64/home/User/gitrepos/lima/pkg/iso9660util/iso9660util.go:53 +0x333
github.com/lima-vm/lima/pkg/cidata.GenerateISO9660({0xc000110060, 0x1c}, {0xc00000a1d0?, 0x0?}, 0xc00012e008, 0xf840, 0xc893, {0xc000074100, 0x7e}, 0x0, ...)
	C:/msys64/home/User/gitrepos/lima/pkg/cidata/cidata.go:432 +0xca8
github.com/lima-vm/lima/pkg/hostagent.New({0xc00000a1d0, 0x7}, {0x1ded3a0, 0xc000295760}, 0xc000518ee0, {0xc0002844f0, 0x1, 0x0?})
	C:/msys64/home/User/gitrepos/lima/pkg/hostagent/hostagent.go:141 +0x3a5
main.hostagentAction(0xc000540c08, {0xc000296d80, 0x1, 0x1bbbfee?})
	C:/msys64/home/User/gitrepos/lima/cmd/limactl/hostagent.go:85 +0x5b7
github.com/spf13/cobra.(*Command).execute(0xc000540c08, {0xc000296c80, 0x8, 0x8})
	C:/Users/User/go/pkg/mod/github.com/spf13/[email protected]/command.go:985 +0xaaa
github.com/spf13/cobra.(*Command).ExecuteC(0xc0002e2908)
	C:/Users/User/go/pkg/mod/github.com/spf13/[email protected]/command.go:1117 +0x3ff
github.com/spf13/cobra.(*Command).Execute(...)
	C:/Users/User/go/pkg/mod/github.com/spf13/[email protected]/command.go:1041
main.main()
	C:/msys64/home/User/gitrepos/lima/cmd/limactl/main.go:28 +0x18

[afbjorklund]

Reproduced the crash, cidata.iso creation now works without converting the path (so it is not needed).