udp: Introduce some `us' convenience variables, etc.

* Introduce appropriate `struct udpsock *us' in a few places, and use
  them as appropriate.  We are going to make a few more places where
  these are used and this avoids some repetition.

* Introduce an `af' variable for the intended destination address
  family at one point.  We are going to want to reuse this.

* Add a comment on a line `} else {' distant from its `if (..) {'.

No functional change.

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>

diff --git a/udp.c b/udp.c
index 5ad0fd44fd6b175e34d2aaf0c1b60135854d6873..f710250af1a8ed230151bc4db82037d320192610 100644 (file)
--- a/udp.c
+++ b/udp.c
@@ -85,10 +85,11 @@ static void udp_socks_afterpoll(void *state, struct pollfd *fds, int nfds)
     struct commcommon *cc=&uc->cc;
 
     for (i=0; i<socks->n_socks; i++) {
+       struct udpsock *us=&socks->socks[i];
        if (i>=nfds) continue;
        if (!(fds[i].revents & POLLIN)) continue;
-       assert(fds[i].fd == socks->socks[i].fd);
-       int fd=socks->socks[i].fd;
+       assert(fds[i].fd == us->fd);
+       int fd=us->fd;
        do {
            fromlen=sizeof(from);
            BUF_ASSERT_FREE(cc->rbuf);
@@ -134,7 +135,7 @@ static void udp_socks_afterpoll(void *state, struct pollfd *fds, int nfds)
                    BUF_FREE(cc->rbuf);
                }
                BUF_ASSERT_FREE(cc->rbuf);
-           } else {
+           } else { /* rv<=0 */
                BUF_FREE(cc->rbuf);
            }
        } while (rv>=0);
@@ -150,6 +151,7 @@ static bool_t udp_sendmsg(void *commst, struct buffer_if *buf,
     uint8_t *sa;
 
     if (uc->use_proxy) {
+       struct udpsock *us=&socks->socks[0];
        sa=buf_prepend(buf,8);
        if (dest->ia.sa.sa_family != AF_INET) {
            Message(M_INFO,
@@ -160,17 +162,19 @@ static bool_t udp_sendmsg(void *commst, struct buffer_if *buf,
        memcpy(sa,&dest->ia.sin.sin_addr,4);
        memset(sa+4,0,4);
        memcpy(sa+6,&dest->ia.sin.sin_port,2);
-       sendto(socks->socks[0].fd,sa,buf->size+8,0,&uc->proxy.sa,
+       sendto(us->fd,sa,buf->size+8,0,&uc->proxy.sa,
               iaddr_socklen(&uc->proxy));
        buf_unprepend(buf,8);
     } else {
        int i,r;
        bool_t allunsupported=True;
+       int af=dest->ia.sa.sa_family;
        for (i=0; i<socks->n_socks; i++) {
-           if (dest->ia.sa.sa_family != socks->socks[i].addr.sa.sa_family)
+           struct udpsock *us=&socks->socks[i];
+           if (us->addr.sa.sa_family != af)
                /* no point even trying */
                continue;
-           r=sendto(socks->socks[i].fd, buf->start, buf->size, 0,
+           r=sendto(us->fd, buf->start, buf->size, 0,
                     &dest->ia.sa, iaddr_socklen(&dest->ia));
            if (r>=0) return True;
            if (!(errno==EAFNOSUPPORT || errno==ENETUNREACH))