Try to untangle the logic in server_port_flush

It's a bit confusing to have a loop where another function,
confusingly named "*_free", is responsible for advancing the loop
variable (or rather, for altering a structure so that the next time
the loop variable's initializer is evaluated it evaluates to something
different.)

Not only has this confused people: it's also confused coverity scan.
Let's fix that.

diff --git a/src/or/eventdns.c b/src/or/eventdns.c
index a504224c54922e9edf9debecb1d11b8e0eaba690..06add11b1da99d3e2f7083801458534d03ee2389 100644 (file)
--- a/src/or/eventdns.c
+++ b/src/or/eventdns.c
@@ -1293,8 +1293,8 @@ server_port_read(struct evdns_server_port *s) {
 static void
 server_port_flush(struct evdns_server_port *port)
 {
-       while (port->pending_replies) {
-               struct server_request *req = port->pending_replies;
+       struct server_request *req = port->pending_replies;
+       while (req) {
                ssize_t r = sendto(port->socket, req->response, req->response_len, 0,
                        (struct sockaddr*) &req->addr, (socklen_t)req->addrlen);
                if (r < 0) {
@@ -1306,6 +1306,9 @@ server_port_flush(struct evdns_server_port *port)
                if (server_request_free(req)) {
                        /* we released the last reference to req->port. */
                        return;
+               } else {
+                       assert(port->pending_replies != req);
+                       req = port->pending_replies;
                }
        }