arping: code shrink
Do not clear extra bits on option_mask32, it's not necessary.
Move DAD bit to 2, this makes exit logic simpler.
function old new delta
arping_main 1655 1629 -26
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/networking/arping.c b/networking/arping.c
index f9967d8..fd2f52c 100644
--- a/networking/arping.c
+++ b/networking/arping.c
@@ -11,7 +11,6 @@
//config: select PLATFORM_LINUX
//config: help
//config: Ping hosts by ARP packets.
-//config:
//applet:IF_ARPING(APPLET(arping, BB_DIR_USR_SBIN, BB_SUID_DROP))
@@ -45,14 +44,23 @@
#define MONOTONIC_US() ((unsigned)monotonic_us())
enum {
- DAD = 1,
- UNSOLICITED = 2,
- ADVERT = 4,
- QUIET = 8,
- QUIT_ON_REPLY = 16,
- BCAST_ONLY = 32,
- UNICASTING = 64
+ UNSOLICITED = 1 << 0,
+ DAD = 1 << 1,
+ ADVERT = 1 << 2,
+ QUIET = 1 << 3,
+ QUIT_ON_REPLY = 1 << 4,
+ BCAST_ONLY = 1 << 5,
+ UNICASTING = 1 << 6,
+ TIMEOUT = 1 << 7,
};
+#define GETOPT32(str_timeout, device, source) \
+ getopt32(argv, "^" \
+ "UDAqfbc:+w:I:s:" \
+ /* Dad also sets quit_on_reply, */ \
+ /* Advert also sets unsolicited: */ \
+ "\0" "=1:Df:AU", \
+ &count, &str_timeout, &device, &source \
+ );
struct globals {
struct in_addr src;
@@ -92,21 +100,15 @@
count = -1; \
} while (0)
-// If GNUisms are not available...
-//static void *mempcpy(void *_dst, const void *_src, int n)
-//{
-// memcpy(_dst, _src, n);
-// return (char*)_dst + n;
-//}
-
static int send_pack(struct in_addr *src_addr,
- struct in_addr *dst_addr, struct sockaddr_ll *ME,
+ struct in_addr *dst_addr,
+ struct sockaddr_ll *ME,
struct sockaddr_ll *HE)
{
int err;
unsigned char buf[256];
struct arphdr *ah = (struct arphdr *) buf;
- unsigned char *p = (unsigned char *) (ah + 1);
+ unsigned char *p;
ah->ar_hrd = htons(ARPHRD_ETHER);
ah->ar_pro = htons(ETH_P_IP);
@@ -114,6 +116,7 @@
ah->ar_pln = 4;
ah->ar_op = option_mask32 & ADVERT ? htons(ARPOP_REPLY) : htons(ARPOP_REQUEST);
+ p = (unsigned char *) (ah + 1);
p = mempcpy(p, &ME->sll_addr, ah->ar_hln);
p = mempcpy(p, src_addr, 4);
@@ -303,16 +306,9 @@
unsigned opt;
char *str_timeout;
- /* Dad also sets quit_on_reply.
- * Advert also sets unsolicited.
- */
- opt = getopt32(argv, "^" "DUAqfbc:+w:I:s:" "\0" "=1:Df:AU",
- &count, &str_timeout, &device, &source
- );
- if (opt & 0x80) /* -w: timeout */
+ opt = GETOPT32(str_timeout, device, source);
+ if (opt & TIMEOUT)
timeout_us = xatou_range(str_timeout, 0, INT_MAX/2000000) * 1000000 + 500000;
- //if (opt & 0x200) /* -s: source */
- option_mask32 &= 0x3f; /* set respective flags */
}
target = argv[optind];
@@ -336,7 +332,9 @@
}
if (ifr.ifr_flags & (IFF_NOARP | IFF_LOOPBACK)) {
bb_error_msg(err_str, "is not ARPable");
- return (option_mask32 & DAD ? 0 : 2);
+ BUILD_BUG_ON(DAD != 2);
+ /* exit 0 if DAD, else exit 2 */
+ return (~option_mask32 & DAD);
}
}
@@ -401,7 +399,9 @@
}
if (me.sll_halen == 0) {
bb_error_msg(err_str, "is not ARPable (no ll address)");
- return (option_mask32 & DAD ? 0 : 2);
+ BUILD_BUG_ON(DAD != 2);
+ /* exit 0 if DAD, else exit 2 */
+ return (~option_mask32 & DAD);
}
he = me;
memset(he.sll_addr, -1, he.sll_halen);