arping: make help text clearer

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

diff --git a/networking/arping.c b/networking/arping.c
index dbfd75ef52da712393cca1c81c13d8cb31a84560..8be1aac2c8ed661de055ef7a6fbc7de2130f28b0 100644 (file)
--- a/networking/arping.c
+++ b/networking/arping.c
@@ -13,11 +13,11 @@
 //usage:     "\n       -f              Quit on first ARP reply"
 //usage:     "\n       -q              Quiet"
 //usage:     "\n       -b              Keep broadcasting, don't go unicast"
-//usage:     "\n       -D              Duplicated address detection mode"
+//usage:     "\n       -D              Exit with 1 if DST_IP replies"
 //usage:     "\n       -U              Unsolicited ARP mode, update your neighbors"
 //usage:     "\n       -A              ARP answer mode, update your neighbors"
 //usage:     "\n       -c N            Stop after sending N ARP requests"
-//usage:     "\n       -w TIMEOUT      Time to wait for ARP reply, seconds"
+//usage:     "\n       -w TIMEOUT      Seconds to wait for ARP reply"
 //usage:     "\n       -I IFACE        Interface to use (default eth0)"
 //usage:     "\n       -s SRC_IP       Sender IP address"
 //usage:     "\n       DST_IP          Target IP address"
@@ -162,7 +162,7 @@ static void catcher(void)
        alarm(1);
 }
 
-static bool recv_pack(unsigned char *buf, int len, struct sockaddr_ll *FROM)
+static void recv_pack(unsigned char *buf, int len, struct sockaddr_ll *FROM)
 {
        struct arphdr *ah = (struct arphdr *) buf;
        unsigned char *p = (unsigned char *) (ah + 1);
@@ -181,33 +181,33 @@ static bool recv_pack(unsigned char *buf, int len, struct sockaddr_ll *FROM)
        if (FROM->sll_pkttype != PACKET_HOST
         && FROM->sll_pkttype != PACKET_BROADCAST
         && FROM->sll_pkttype != PACKET_MULTICAST)
-               return false;
+               return;
 
        /* Only these types are recognized */
        if (ah->ar_op != htons(ARPOP_REQUEST) && ah->ar_op != htons(ARPOP_REPLY))
-               return false;
+               return;
 
        /* ARPHRD check and this darned FDDI hack here :-( */
        if (ah->ar_hrd != htons(FROM->sll_hatype)
         && (FROM->sll_hatype != ARPHRD_FDDI || ah->ar_hrd != htons(ARPHRD_ETHER)))
-               return false;
+               return;
 
        /* Protocol must be IP. */
        if (ah->ar_pro != htons(ETH_P_IP)
         || (ah->ar_pln != 4)
         || (ah->ar_hln != me.sll_halen)
         || (len < (int)(sizeof(*ah) + 2 * (4 + ah->ar_hln))))
-               return false;
+               return;
 
        move_from_unaligned32(src_ip.s_addr, p + ah->ar_hln);
        move_from_unaligned32(dst_ip.s_addr, p + ah->ar_hln + 4 + ah->ar_hln);
 
        if (dst.s_addr != src_ip.s_addr)
-               return false;
+               return;
        if (!(option_mask32 & DAD)) {
                if ((src.s_addr != dst_ip.s_addr)
-                       || (memcmp(p + ah->ar_hln + 4, &me.sll_addr, ah->ar_hln)))
-                       return false;
+                || (memcmp(p + ah->ar_hln + 4, &me.sll_addr, ah->ar_hln)))
+                       return;
        } else {
                /* DAD packet was:
                   src_ip = 0 (or some src)
@@ -224,7 +224,7 @@ static bool recv_pack(unsigned char *buf, int len, struct sockaddr_ll *FROM)
                 */
                if ((memcmp(p, &me.sll_addr, me.sll_halen) == 0)
                 || (src.s_addr && src.s_addr != dst_ip.s_addr))
-                       return false;
+                       return;
        }
        if (!(option_mask32 & QUIET)) {
                int s_printed = 0;
@@ -264,7 +264,6 @@ static bool recv_pack(unsigned char *buf, int len, struct sockaddr_ll *FROM)
                memcpy(he.sll_addr, p, me.sll_halen);
                option_mask32 |= UNICASTING;
        }
-       return true;
 }
 
 int arping_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;