lkml.org 
[lkml]   [2014]   [Oct]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: kdbus: add header file
Date
On Wednesday 29 October 2014 15:00:46 Greg Kroah-Hartman wrote:
> +enum kdbus_ioctl_type {
> + KDBUS_CMD_BUS_MAKE = _IOW(KDBUS_IOCTL_MAGIC, 0x00,
> + struct kdbus_cmd_make),
> + KDBUS_CMD_DOMAIN_MAKE = _IOW(KDBUS_IOCTL_MAGIC, 0x10,
> + struct kdbus_cmd_make),
> + KDBUS_CMD_ENDPOINT_MAKE = _IOW(KDBUS_IOCTL_MAGIC, 0x20,
> + struct kdbus_cmd_make),
> +
> + KDBUS_CMD_HELLO = _IOWR(KDBUS_IOCTL_MAGIC, 0x30,
> + struct kdbus_cmd_hello),
> + KDBUS_CMD_BYEBYE = _IO(KDBUS_IOCTL_MAGIC, 0x31),
> +
> + KDBUS_CMD_MSG_SEND = _IOWR(KDBUS_IOCTL_MAGIC, 0x40,
> + struct kdbus_msg),
> + KDBUS_CMD_MSG_RECV = _IOWR(KDBUS_IOCTL_MAGIC, 0x41,
> + struct kdbus_cmd_recv),
> + KDBUS_CMD_MSG_CANCEL = _IOW(KDBUS_IOCTL_MAGIC, 0x42,
> + struct kdbus_cmd_cancel),
> + KDBUS_CMD_FREE = _IOW(KDBUS_IOCTL_MAGIC, 0x43,
> + struct kdbus_cmd_free),
>

I think in general, using enum is great, but for ioctl command numbers,
we probably want to have defines so the user space implementation can
use #ifdef to see if the kernel version that it is being built for
knows a particular command.

You could do that using

#define KDBUS_CMD_BUS_MAKE KDBUS_CMD_BUS_MAKE

while keeping the enum, or do it like everybody else using

#define KDBUS_CMD_BUS_MAKE _IOW(KDBUS_IOCTL_MAGIC, 0x00, struct kdbus_cmd_make)

which might in fact help some tools that try to do automated parsing
of header files to find ioctl commands.

Arnd


\
 
 \ /
  Last update: 2014-10-30 10:01    [W:0.103 / U:4.348 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site