rx: Save errno in LWP rxi_Sendmsg

Much of this code examines errno or WSAGetLastError to determine what
to do. However, some other operations between the actual sendmsg call
and code that examines errno may modify errno. So, save the value of
errno to ensure errno reflects the actual error we got from sendmsg;
this also slightly simplifies some of the logic.

Change-Id: I5a8643fce5d2e29131069743b14805bbc2428805
Reviewed-on: http://gerrit.openafs.org/8110
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
Tested-by: BuildBot <buildbot@rampaginggeek.com>

diff --git a/src/rx/rx_lwp.c b/src/rx/rx_lwp.c
index e6ae068..fe9bdce 100644 (file)
--- a/src/rx/rx_lwp.c
+++ b/src/rx/rx_lwp.c
@@ -429,6 +429,13 @@ rxi_Sendmsg(osi_socket socket, struct msghdr *msg_p, int flags)
     fd_set *sfds = (fd_set *) 0;
     while (sendmsg(socket, msg_p, flags) == -1) {
        int err;
+
+#ifdef AFS_NT40_ENV
+       err = WSAGetLastError();
+#else
+       err = errno;
+#endif
+
        if (rx_stats_active)
            rx_atomic_inc(&rx_stats.sendSelects);
 
@@ -445,26 +452,21 @@ rxi_Sendmsg(osi_socket socket, struct msghdr *msg_p, int flags)
          ;
 #endif
 #ifdef AFS_NT40_ENV
-       if (WSAGetLastError())
+       if (err)
 #elif defined(AFS_LINUX22_ENV)
        /* linux unfortunately returns ECONNREFUSED if the target port
         * is no longer in use */
        /* and EAGAIN if a UDP checksum is incorrect */
-       if (errno != EWOULDBLOCK && errno != ENOBUFS && errno != ECONNREFUSED
-           && errno != EAGAIN)
+       if (err != EWOULDBLOCK && err != ENOBUFS && err != ECONNREFUSED
+           && err != EAGAIN)
 #else
-       if (errno != EWOULDBLOCK && errno != ENOBUFS)
+       if (err != EWOULDBLOCK && err != ENOBUFS)
 #endif
        {
            (osi_Msg "rx failed to send packet: ");
            perror("rx_sendmsg");
-#ifndef AFS_NT40_ENV
-            if (errno > 0)
-              return -errno;
-#else
-            if (WSAGetLastError() > 0)
-              return -WSAGetLastError();
-#endif
+            if (err > 0)
+              return -err;
            return -1;
        }
        while ((err = select(