From: Remi Gacogne <remi.gacogne@powerdns.com>
Date: Fri, 10 Jun 2016 12:29:31 +0000 (+0200)
Subject: auth: Handle `read()` returning 0 in RemoteBackend's unix connector
X-Git-Tag: auth-4.0.0-rc1~51^2~3^2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=refs%2Fpull%2F3973%2Fhead;p=thirdparty%2Fpdns.git

auth: Handle `read()` returning 0 in RemoteBackend's unix connector

Otherwise it looks like we may loop in `recv_message()` until the
timeout is reached if the other end closes the connection:
* `waitForData()` will return immediately
* `read()` will keep returning 0
---

diff --git a/modules/remotebackend/unixconnector.cc b/modules/remotebackend/unixconnector.cc
index 5c5a7216fc..f997183e21 100644
--- a/modules/remotebackend/unixconnector.cc
+++ b/modules/remotebackend/unixconnector.cc
@@ -89,7 +89,7 @@ ssize_t UnixsocketConnector::read(std::string &data) {
   // just try again later...
   if (nread==-1 && errno == EAGAIN) return 0;
 
-  if (nread==-1) {
+  if (nread==-1 || nread==0) {
     connected = false;
     close(fd);
     return -1;