[PATCH v3] netifd: add devtype to ubus call

[Florian Eckert]

Hello Hans,

thanks for you review.

>> +--- a/system.h
>> ++++ b/system.h
>> +@@ -23,6 +23,42 @@
>> + #include "iprule.h"
>> + #include "utils.h"
>> +
>> ++static const unsigned short netdev_type_number[] = {
>> ++      ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25,
>> ++      ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET,
>> ++      ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM,
>> ++      ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP,
>> ++      ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD,
>> ++      ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25,
>> ++      ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP,
>> ++      ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD,
>> ++      ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI,
>> ++      ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE,
>> ++      ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET,
>> ++      ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL,
>> ++      ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM,
>> ++      ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE,
>> ++      ARPHRD_IEEE802154, ARPHRD_VOID, ARPHRD_NONE
>> ++};
>> ++
>> ++static const char *const netdev_type_name[] = {
>> ++      "netrom", "ethernet", "eethernet", "ax25",
>> ++      "pronet", "chaos", "ieee802", "arcnet",
>> ++      "appletlk", "dlci", "atm", "metricom",
>> ++      "ieee1394", "eui64", "infiniband", "slip",
>> ++      "cslip", "slip6", "cslip6", "rsrvd",
>> ++      "adapt", "rose", "x25", "hwx25",
>> ++      "ppp", "cisco", "lapb", "ddcmp",
>> ++      "rawhdlc", "tunnel", "tunnel6", "frad",
>> ++      "skip", "loopback", "localtlk", "fddi",
>> ++      "bif", "sit", "ipddp", "ipgre",
>> ++      "pimreg", "hippi", "ash", "econet",
>> ++      "irda", "fcpp", "fcal", "fcpl",
>> ++      "fcfabric", "ieee80211", "ie80211-prism",
>> ++      "ieee80211-radiotap", "phonet", "phonet-pipe",
>> ++      "ieee802154", "void", "none"
>> ++};
> Merge these two arrays into one array, each entry having the netdev
> type number and the corresponding string.
> Implement a function which uses the array and takes as argument the
> netdev type number and returns the corresponding string

I am not quite sure if I have understood this correctly.
If you take a look at the include where the ARPHRD are defined.
https://elixir.bootlin.com/linux/v5.16-rc1/source/include/uapi/linux/if_arp.h
Then the array must have 65535 entries ARPHRD_VOID is at position 
0xFFFF.
That's quite a lot for the fact that there are 58 ids.

This is the code I would use?

static const char * const netdev_type[] = {
  [ARPHRD_NETROM] = "netrom",
  [ARPHRD_ETHER] = "ethernet",
...
...
};

Or should I define an array of netdev_type structs?

struct netdev_type {
   const char *name;
   unsigned short number;
};

#define DEV_TYPE(_name, _number) \
{                                \
   .name = _name,                 \
   .number = _number              \
}                                \


static const struct netdev_type netdev_types[] = {
{
   DEV_TYPE("netrom", ARPHRD_NETROM),
   DEV_TYPE("ethernet", ARPHRD_ETHER),
...
...
};

Best Regards
Florian