Search code examples
goio-uring

Convert `ioctl` call in golang

I'm trying to convert, or at least understand this ioctl call:

#define NVME_URING_CMD_IO   _IOWR('N', 0x80, struct nvme_uring_cmd)

Is there an equivalent of _IOWR in golang? maybe with the unix package?

Solution

  • Ok, I managed to convert it, thanks to help in comments:

    
const (
    IocNrBits           = 8
    IocTypeBits         = 8
    IocSizeBits         = 14
    IocNrShift          = 0
    IocRead     uintptr = 2
    IocWrite    uintptr = 2
)

const (
    IocTypeShift = IocNrShift + IocNrBits
    IocSizeShift = IocTypeShift + IocTypeBits
    IocDirshift  = IocSizeShift + IocSizeBits
)

func IOC(dir, t, nr, size uintptr) uintptr {
    return (dir << IocDirshift) |
        (t << IocTypeShift) |
        (nr << IocNrShift) |
        (size << IocSizeShift)
}

func IOWR(t, nr, size uintptr) uintptr {
    return IOC(IocRead|IocWrite, t, nr, size)
}

func NVME_URING_CMD_IO() uintptr {
    return IOWR('N', 0x80, 32)
}