Re: [RFC] use <linux/if.h> instead of <net/if.h>

[Dan Williams <dcbw redhat com>]

On Fri, 2011-09-09 at 11:50 +0200, Thomas Graf wrote:
> Use of <net/if.h> conflicts with the use of <linux/if.h>. While users
> of <net/if.h> can switch to <linux/if.h> it is not posible in the
> other direction.
> 
> The header <netlink/route/link.h> uses <linux/if.h> because it is part
> of the API, therefore it conflicts with NM.
> 
> Does NM rely on using <net/if.h> for some reason or can we switch over
> to using <linux/if.h>?

It's being used for some ioctls, it appears.  This patch fails like so:

libtool: compile:  gcc -DHAVE_CONFIG_H -I. -I../.. -I../../src -I../../src/logging -I../../include -I../../libnm-util -I../../marshallers -pthread -I/usr/include/dbus-1.0 -I/usr/lib64/dbus-1.0/include -I/usr/include/glib-2.0 -I/usr/lib64/glib-2.0/include -I/usr/include/wimax -Wall -std=gnu89 -g -O2 -Wshadow -Wmissing-declarations -Wmissing-prototypes -Wdeclaration-after-statement -Wfloat-equal -Wno-unused-parameter -Wno-sign-compare -fno-strict-aliasing -Wno-unused-but-set-variable -Wundef -Werror -MT libwimax_la-nm-device-wimax.lo -MD -MP -MF .deps/libwimax_la-nm-device-wimax.Tpo -c nm-device-wimax.c  -fPIC -DPIC -o .libs/libwimax_la-nm-device-wimax.o
In file included from nm-device-wimax.c:26:0:
/usr/include/linux/if.h:178:19: error: field 'ifru_addr' has incomplete type
/usr/include/linux/if.h:179:19: error: field 'ifru_dstaddr' has incomplete type
/usr/include/linux/if.h:180:19: error: field 'ifru_broadaddr' has incomplete type
/usr/include/linux/if.h:181:19: error: field 'ifru_netmask' has incomplete type
/usr/include/linux/if.h:182:20: error: field 'ifru_hwaddr' has incomplete type

and removing the include cause:

nm-device-wimax.c: In function 'real_update_hw_address':
nm-device-wimax.c:418:15: error: storage size of 'req' isn't known
nm-device-wimax.c:430:27: error: invalid application of 'sizeof' to incomplete type 'struct ifreq' 
nm-device-wimax.c:418:15: error: unused variable 'req' [-Werror=unused-variable]

because we're trying to:

	if (ioctl (fd, SIOCGIFHWADDR, &req) < 0) {

which is used in a couple other places. We could conceivably convert
this to use libnl in synchronous mode.  There's other usage of ioctl()
in the NM codebase, mainly for WEXT (which we should replace with
nl80211, which is part of the reason for the libnl3 conversion) but also
for SIOCETHTOOL, SIOCGMIIREG, SIOCGMIIPHY, and SIOCGPPPSTATS.

What's the best course forward here?

Dan

> ---
>  include/wireless-helper.h              |    2 +-
>  src/nm-device.c                        |    2 +-
>  src/nm-system.c                        |    2 +-
>  src/ppp-manager/nm-ppp-manager.c       |    2 +-
>  src/settings/plugins/ifcfg-rh/reader.c |    2 +-
>  src/wimax/iwmxsdk.c                    |    2 +-
>  src/wimax/nm-device-wimax.c            |    2 +-
>  7 files changed, 7 insertions(+), 7 deletions(-)
> 
> diff --git a/include/wireless-helper.h b/include/wireless-helper.h
> index d150ef7..2e4509a 100644
> --- a/include/wireless-helper.h
> +++ b/include/wireless-helper.h
> @@ -27,6 +27,6 @@
>  #include <sys/types.h>
>  #include <linux/types.h>
>  #include <sys/socket.h>
> -#include <net/if.h>
> +#include <linux/if.h>
>  #include <wireless.h>
>  
> diff --git a/src/nm-device.c b/src/nm-device.c
> index 3522ea4..a453c39 100644
> --- a/src/nm-device.c
> +++ b/src/nm-device.c
> @@ -25,7 +25,7 @@
>  #include <dbus/dbus.h>
>  #include <netinet/in.h>
>  #include <string.h>
> -#include <net/if.h>
> +#include <linux/if.h>
>  #include <unistd.h>
>  #include <errno.h>
>  #include <sys/ioctl.h>
> diff --git a/src/nm-system.c b/src/nm-system.c
> index 0b29468..473fcec 100644
> --- a/src/nm-system.c
> +++ b/src/nm-system.c
> @@ -40,7 +40,7 @@
>  #include <netdb.h>
>  #include <glib.h>
>  #include <ctype.h>
> -#include <net/if.h>
> +#include <linux/if.h>
>  
>  #include "nm-system.h"
>  #include "nm-device.h"
> diff --git a/src/ppp-manager/nm-ppp-manager.c b/src/ppp-manager/nm-ppp-manager.c
> index e863aab..9d8b79e 100644
> --- a/src/ppp-manager/nm-ppp-manager.c
> +++ b/src/ppp-manager/nm-ppp-manager.c
> @@ -32,7 +32,7 @@
>  #include <sys/socket.h>
>  #include <sys/ioctl.h>
>  #include <asm/types.h>
> -#include <net/if.h>
> +#include <linux/if.h>
>  #include <sys/stat.h>
>  
>  #include <linux/ppp_defs.h>
> diff --git a/src/settings/plugins/ifcfg-rh/reader.c b/src/settings/plugins/ifcfg-rh/reader.c
> index cdf5889..a33332a 100644
> --- a/src/settings/plugins/ifcfg-rh/reader.c
> +++ b/src/settings/plugins/ifcfg-rh/reader.c
> @@ -28,7 +28,7 @@
>  #include <ctype.h>
>  #include <sys/inotify.h>
>  #include <errno.h>
> -#include <net/if.h>
> +#include <linux/if.h>
>  #include <sys/ioctl.h>
>  #include <unistd.h>
>  #include <netinet/ether.h>
> diff --git a/src/wimax/iwmxsdk.c b/src/wimax/iwmxsdk.c
> index dd78d5a..f9dc714 100644
> --- a/src/wimax/iwmxsdk.c
> +++ b/src/wimax/iwmxsdk.c
> @@ -27,7 +27,7 @@
>  #include <stdlib.h>
>  #include <errno.h>
>  #include <string.h>
> -#include <net/if.h>
> +#include <linux/if.h>
>  
>  #include <glib.h>
>  
> diff --git a/src/wimax/nm-device-wimax.c b/src/wimax/nm-device-wimax.c
> index d41491a..ec23520 100644
> --- a/src/wimax/nm-device-wimax.c
> +++ b/src/wimax/nm-device-wimax.c
> @@ -23,7 +23,7 @@
>  #include <unistd.h>
>  #include <sys/ioctl.h>
>  #include <net/ethernet.h>
> -#include <net/if.h>
> +#include <linux/if.h>
>  
>  #include <WiMaxAPI.h>
>  #include <WiMaxAPIEx.h>