*: remove check for errors on getsockaddr in cases we know they can't happen

libbb: make get_sock_lsa use only one getsockaddr syscall, not two

function                                             old     new   delta
get_sock_lsa                                          72     101     +29
do_iplink                                           1151    1137     -14
arping_main                                         1585    1569     -16
dolisten                                             789     755     -34
xrtnl_open                                           161      94     -67

diff --git a/libbb/xconnect.c b/libbb/xconnect.c
index 1b4f4f78affa01e5b3f5bb1a0bbf857cff294914..f853e95934375b9b232bb909874c1f2d489cfd81 100644 (file)
--- a/libbb/xconnect.c
+++ b/libbb/xconnect.c
@@ -37,16 +37,21 @@ int FAST_FUNC setsockopt_bindtodevice(int fd, const char *iface)
 
 len_and_sockaddr* FAST_FUNC get_sock_lsa(int fd)
 {
-       len_and_sockaddr *lsa;
-       socklen_t len = 0;
+       len_and_sockaddr lsa;
+       len_and_sockaddr *lsa_ptr;
 
-       /* Can be optimized to do only one getsockname() */
-       if (getsockname(fd, NULL, &len) != 0)
+       lsa.len = LSA_SIZEOF_SA;
+       if (getsockname(fd, &lsa.u.sa, &lsa.len) != 0)
                return NULL;
-       lsa = xzalloc(LSA_LEN_SIZE + len);
-       lsa->len = len;
-       getsockname(fd, &lsa->u.sa, &lsa->len);
-       return lsa;
+
+       lsa_ptr = xzalloc(LSA_LEN_SIZE + lsa.len);
+       if (lsa.len > LSA_SIZEOF_SA) { /* rarely (if ever) happens */
+               lsa_ptr->len = lsa.len;
+               getsockname(fd, &lsa_ptr->u.sa, &lsa_ptr->len);
+       } else {
+               memcpy(lsa_ptr, &lsa, LSA_LEN_SIZE + lsa.len);
+       }
+       return lsa_ptr;
 }
 
 void FAST_FUNC xconnect(int s, const struct sockaddr *s_addr, socklen_t addrlen)

diff --git a/networking/arping.c b/networking/arping.c
index 915af326187525fd0f1b25e9cb229779ca060887..ab39c717b6c7249a5ff4ff6dd73555fdd20d7ef5 100644 (file)
--- a/networking/arping.c
+++ b/networking/arping.c
@@ -348,9 +348,10 @@ int arping_main(int argc UNUSED_PARAM, char **argv)
                        if (setsockopt(probe_fd, SOL_SOCKET, SO_DONTROUTE, &const_int_1, sizeof(const_int_1)) == -1)
                                bb_perror_msg("setsockopt(SO_DONTROUTE)");
                        xconnect(probe_fd, (struct sockaddr *) &saddr, sizeof(saddr));
-                       if (getsockname(probe_fd, (struct sockaddr *) &saddr, &alen) == -1) {
-                               bb_perror_msg_and_die("getsockname");
-                       }
+                       getsockname(probe_fd, (struct sockaddr *) &saddr, &alen);
+                       //never happens:
+                       //if (getsockname(probe_fd, (struct sockaddr *) &saddr, &alen) == -1)
+                       //      bb_perror_msg_and_die("getsockname");
                        if (saddr.sin_family != AF_INET)
                                bb_error_msg_and_die("no IP address configured");
                        src = saddr.sin_addr;
@@ -365,10 +366,10 @@ int arping_main(int argc UNUSED_PARAM, char **argv)
 
        {
                socklen_t alen = sizeof(me);
-
-               if (getsockname(sock_fd, (struct sockaddr *) &me, &alen) == -1) {
-                       bb_perror_msg_and_die("getsockname");
-               }
+               getsockname(sock_fd, (struct sockaddr *) &me, &alen);
+               //never happens:
+               //if (getsockname(sock_fd, (struct sockaddr *) &me, &alen) == -1)
+               //      bb_perror_msg_and_die("getsockname");
        }
        if (me.sll_halen == 0) {
                bb_error_msg(err_str, "is not ARPable (no ll address)");

diff --git a/networking/libiproute/iplink.c b/networking/libiproute/iplink.c
index 1e7ee07d2208c99871cba88990fbe857db810c5a..de7d6407e21da37f5829584c72c424dd76d57b5e 100644 (file)
--- a/networking/libiproute/iplink.c
+++ b/networking/libiproute/iplink.c
@@ -112,11 +112,11 @@ static int get_address(char *dev, int *htype)
        me.sll_ifindex = ifr.ifr_ifindex;
        me.sll_protocol = htons(ETH_P_LOOP);
        xbind(s, (struct sockaddr*)&me, sizeof(me));
-
        alen = sizeof(me);
-       if (getsockname(s, (struct sockaddr*)&me, &alen) == -1) {
-               bb_perror_msg_and_die("getsockname");
-       }
+       getsockname(s, (struct sockaddr*)&me, &alen);
+       //never happens:
+       //if (getsockname(s, (struct sockaddr*)&me, &alen) == -1)
+       //      bb_perror_msg_and_die("getsockname");
        close(s);
        *htype = me.sll_hatype;
        return me.sll_halen;

diff --git a/networking/libiproute/libnetlink.c b/networking/libiproute/libnetlink.c
index 6d51d8deba9e182b16a25e07a3e8a226130bf43a..7ad2de9fa1f0fa9775bb56d559f05be5de25c764 100644 (file)
--- a/networking/libiproute/libnetlink.c
+++ b/networking/libiproute/libnetlink.c
@@ -26,22 +26,23 @@ int FAST_FUNC xrtnl_open(struct rtnl_handle *rth/*, unsigned subscriptions*/)
 {
        socklen_t addr_len;
 
-       memset(rth, 0, sizeof(rth));
-
+       memset(rth, 0, sizeof(*rth));
        rth->fd = xsocket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
-
-       memset(&rth->local, 0, sizeof(rth->local));
        rth->local.nl_family = AF_NETLINK;
        /*rth->local.nl_groups = subscriptions;*/
 
        xbind(rth->fd, (struct sockaddr*)&rth->local, sizeof(rth->local));
        addr_len = sizeof(rth->local);
+       getsockname(rth->fd, (struct sockaddr*)&rth->local, &addr_len);
+
+/* too much paranoia
        if (getsockname(rth->fd, (struct sockaddr*)&rth->local, &addr_len) < 0)
                bb_perror_msg_and_die("getsockname");
        if (addr_len != sizeof(rth->local))
                bb_error_msg_and_die("wrong address length %d", addr_len);
        if (rth->local.nl_family != AF_NETLINK)
                bb_error_msg_and_die("wrong address family %d", rth->local.nl_family);
+*/
        rth->seq = time(NULL);
        return 0;
 }

diff --git a/networking/libiproute/libnetlink.h b/networking/libiproute/libnetlink.h
index e5fee4dd810cadeef0bb9ee54107390664912cda..11a4a100afd00201b6f81f5b84f0ad66de456cf1 100644 (file)
--- a/networking/libiproute/libnetlink.h
+++ b/networking/libiproute/libnetlink.h
@@ -10,8 +10,7 @@
 
 PUSH_AND_SET_FUNCTION_VISIBILITY_TO_HIDDEN
 
-struct rtnl_handle
-{
+struct rtnl_handle {
        int                     fd;
        struct sockaddr_nl      local;
        struct sockaddr_nl      peer;

diff --git a/networking/nc_bloaty.c b/networking/nc_bloaty.c
index 47940e9b308dded1e035e6cf54406c8467c02447..efe831ec303e45e6b6257abc3fca846e0e012d77 100644 (file)
--- a/networking/nc_bloaty.c
+++ b/networking/nc_bloaty.c
@@ -278,9 +278,9 @@ static void dolisten(void)
         random unknown port is probably not very useful without "netstat". */
        if (o_verbose) {
                char *addr;
-               rr = getsockname(netfd, &ouraddr->u.sa, &ouraddr->len);
-               if (rr < 0)
-                       bb_perror_msg_and_die("getsockname after bind");
+               getsockname(netfd, &ouraddr->u.sa, &ouraddr->len);
+               //if (rr < 0)
+               //      bb_perror_msg_and_die("getsockname after bind");
                addr = xmalloc_sockaddr2dotted(&ouraddr->u.sa);
                fprintf(stderr, "listening on %s ...\n", addr);
                free(addr);
@@ -359,9 +359,9 @@ create new one, and bind() it. TODO */
                 doing a listen-on-any on a multihomed machine.  This allows one to
                 offer different services via different alias addresses, such as the
                 "virtual web site" hack. */
-               rr = getsockname(netfd, &ouraddr->u.sa, &ouraddr->len);
-               if (rr < 0)
-                       bb_perror_msg_and_die("getsockname after accept");
+               getsockname(netfd, &ouraddr->u.sa, &ouraddr->len);
+               //if (rr < 0)
+               //      bb_perror_msg_and_die("getsockname after accept");
        }
 
        if (o_verbose) {