Resolver: added missing event handling after reading.

If we need to be notified about further events, ngx_handle_read_event()
needs to be called after a read event is processed.  Without this,
an event can be removed from the kernel and won't be reported again,
notably when using oneshot event methods, such as eventport on Solaris.

While here, error handling is also added, similar to one present in
ngx_resolver_tcp_read().  This is not expected to make a difference
and mostly added for consistency.

diff --git a/src/core/ngx_resolver.c b/src/core/ngx_resolver.c
index 5b716ee75c31372e2e40c0480097bc48d811e12b..49616b77632fcee0c5e1a55461f1c55f0e3e286a 100644 (file)
--- a/src/core/ngx_resolver.c
+++ b/src/core/ngx_resolver.c
@@ -1563,13 +1563,28 @@ ngx_resolver_udp_read(ngx_event_t *rev)
     do {
         n = ngx_udp_recv(c, buf, NGX_RESOLVER_UDP_SIZE);
 
-        if (n < 0) {
-            return;
+        if (n == NGX_AGAIN) {
+            break;
+        }
+
+        if (n == NGX_ERROR) {
+            goto failed;
         }
 
         ngx_resolver_process_response(rec->resolver, buf, n, 0);
 
     } while (rev->ready);
+
+    if (ngx_handle_read_event(rev, 0) != NGX_OK) {
+        goto failed;
+    }
+
+    return;
+
+failed:
+
+    ngx_close_connection(rec->udp);
+    rec->udp = NULL;
 }