Recently, I've been reading the source code of WireGuard. The function name like ipc_get_device() looks to be a little bit misleading. To make the code more readable for new developers, here are some suggestions:

• Rename ipc_get_device(&dev) to ipc_fetch_conf(&conf) because it only fetches the runtime configuations from kernel.
• Change funtion prototype ipc_set_device(struct wgdevice *dev) to ipc_set_device(const struct wgdevice *newconf).

Change the following IPC function names and parameters which used to be confusing:

- ipc_set_device(dev)                  => ipc_set_device(newconf)
- ipc_get_device(dev, interface)       => ipc_fetch_conf(conf, interface)
- kernel_set_device(dev)               => kernel_set_device(newconf)
- kernel_get_device(device, interface) => kernel_fetch_conf(conf, interface)
- userspace_set_device(dev)            => userspace_set_device(newconf)
- userspace_get_device(out, interface) => userspace_fetch_conf(out, interface)

- free_wgdevice(dev) => free_conf(conf)

Renamed local variable/parameter symbols:

• In showconf_main(), show_main():
  device => conf
• In ipc_fetch_conf(), kernel_fetch_conf(), userspace_fetch_conf():
  dev => conf
• In ipc_set_device(), kernel_set_device(), userspace_set_device():
  dev => newconf

Note:
A lot of braces are added to the if-else code blocks to keep ourselves from making unexpected mistakes in the future.

Changed function prototypes:

• int ipc_set_device(struct wgdevice *) => int ipc_set_device(const struct wgdevice *newconf)
• int kernel_set_device(struct wgdevice *) => int kernel_set_device(const struct wgdevice *newconf)
• int userspace_set_device(struct wgdevice *) => int userspace_set_device(const struct wgdevice *newconf)

• free_conf()