ifplugd: code shrink; expanded comments

Signed-off-by: Maxim Kryzhanovsky <xmaks@email.cz>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Maxim Kryzhanovsky 2010-03-30 15:49:57 +02:00 committed by Denys Vlasenko
parent eab75f6049
commit 2004fa1bc8

View File

@ -1,6 +1,6 @@
/* vi: set sw=4 ts=4: */
/*
* ifplugd for busybox
* ifplugd for busybox, based on ifplugd 0.28 (written by Lennart Poettering).
*
* Copyright (C) 2009 Maksym Kryzhanovskyy <xmaks@email.cz>
*
@ -22,7 +22,11 @@
#include <linux/wireless.h>
/*
TODO: describe compat status here.
From initial port to busybox, removed most of the redundancy by
converting implementation of a polymorphic interface to the strict
functional style. The main role is run a script when link state
changed, other activities like audio signal or detailed reports
are on the script itself.
One questionable point of the design is netlink usage:
@ -500,38 +504,30 @@ static NOINLINE int check_existence_through_netlink(void)
mhdr = (struct nlmsghdr*)replybuf;
while (bytes > 0) {
if (!NLMSG_OK(mhdr, bytes)
|| bytes < sizeof(struct nlmsghdr)
|| bytes < mhdr->nlmsg_len
) {
if (!NLMSG_OK(mhdr, bytes)) {
bb_error_msg("netlink packet too small or truncated");
return -1;
}
if (mhdr->nlmsg_type == RTM_NEWLINK || mhdr->nlmsg_type == RTM_DELLINK) {
struct rtattr *attr;
struct ifinfomsg *imsg;
int attr_len;
imsg = NLMSG_DATA(mhdr);
if (mhdr->nlmsg_len < NLMSG_LENGTH(sizeof(struct ifinfomsg))) {
bb_error_msg("netlink packet too small or truncated");
return -1;
}
attr = (struct rtattr*)((char*)imsg + NLMSG_ALIGN(sizeof(struct ifinfomsg)));
attr_len = NLMSG_PAYLOAD(mhdr, sizeof(struct ifinfomsg));
attr = IFLA_RTA(NLMSG_DATA(mhdr));
attr_len = IFLA_PAYLOAD(mhdr);
while (RTA_OK(attr, attr_len)) {
if (attr->rta_type == IFLA_IFNAME) {
char ifname[IFNAMSIZ + 1];
int len = RTA_PAYLOAD(attr);
if (len > IFNAMSIZ)
len = IFNAMSIZ;
memcpy(ifname, RTA_DATA(attr), len);
if (strcmp(G.iface, ifname) == 0) {
if (strncmp(G.iface, RTA_DATA(attr), len) == 0) {
G.iface_exists = (mhdr->nlmsg_type == RTM_NEWLINK);
}
}