krb5 commit [krb5-1.14]: Properly handle EOF condition on libkrad sockets

[Tom Yu]

https://github.com/krb5/krb5/commit/10d20626a327213f05578d7dffb4d02ddfce5b0f
commit 10d20626a327213f05578d7dffb4d02ddfce5b0f
Author: Nathaniel McCallum <npmccallum at redhat.com>
Date:   Fri Sep 30 10:03:33 2016 -0400

    Properly handle EOF condition on libkrad sockets
    
    In the previous code, when the remote peer performed an orderly shutdown
    on the socket, libkrad would enter a state in which all future requests
    timed out.  Instead, if the peer shuts down its socket, we need to
    attempt to reopen it.
    
    (cherry picked from commit 248497427d5a45225817b6c22e9224e8ad969872)
    
    ticket: 8504
    version_fixed: 1.14.5

 src/lib/krad/remote.c |   13 ++++++-------
 1 files changed, 6 insertions(+), 7 deletions(-)

diff --git a/src/lib/krad/remote.c b/src/lib/krad/remote.c
index df3de3a..68cd16f 100644
--- a/src/lib/krad/remote.c
+++ b/src/lib/krad/remote.c
@@ -329,16 +329,15 @@ on_io_read(krad_remote *rr)
     /* Read the packet. */
     i = recv(verto_get_fd(rr->io), rr->buffer.data + rr->buffer.length,
              pktlen, 0);
-    if (i < 0) {
-        /* Should we try again? */
-        if (errno == EWOULDBLOCK || errno == EAGAIN || errno == EINTR)
-            return;
 
-        /* The socket is unrecoverable. */
+    /* On these errors, try again. */
+    if (i < 0 && (errno == EWOULDBLOCK || errno == EAGAIN || errno == EINTR))
+        return;
+
+    /* On any other errors or on EOF, the socket is unrecoverable. */
+    if (i <= 0) {
         remote_shutdown(rr);
         return;
-    } else if (i == 0) {
-        remote_del_flags(rr, FLAGS_READ);
     }
 
     /* If we have a partial read or just the header, try again. */