Merge pull request #2292 from bluca/osx_sigpipe

Problem: peer can close connection before SO_NOSIGPIPE is set

src/ip.cpp

@@ -30,6 +30,7 @@
 #include "precompiled.hpp"
 #include "ip.hpp"
 #include "err.hpp"
+#include "macros.hpp"
 
 #if !defined ZMQ_HAVE_WINDOWS
 #include <fcntl.h>
@@ -46,6 +47,8 @@
 
 zmq::fd_t zmq::open_socket (int domain_, int type_, int protocol_)
 {
+    int rc;
+
     //  Setting this option result in sane behaviour when exec() functions
     //  are used. Old sockets are closed and don't block TCP ports etc.
 #if defined ZMQ_HAVE_SOCK_CLOEXEC
@@ -65,7 +68,7 @@ zmq::fd_t zmq::open_socket (int domain_, int type_, int protocol_)
     //  race condition can cause socket not to be closed (if fork happens
     //  between socket creation and this point).
 #if !defined ZMQ_HAVE_SOCK_CLOEXEC && defined FD_CLOEXEC
-    int rc = fcntl (s, F_SETFD, FD_CLOEXEC);
+    rc = fcntl (s, F_SETFD, FD_CLOEXEC);
     errno_assert (rc != -1);
 #endif
 
@@ -75,6 +78,10 @@ zmq::fd_t zmq::open_socket (int domain_, int type_, int protocol_)
     win_assert (brc);
 #endif
 
+    //  Socket is not yet connected so EINVAL is not a valid networking error
+    rc = zmq::set_nosigpipe (s);
+    errno_assert (rc == 0);
+
     return s;
 }
 
@@ -190,3 +197,23 @@ void zmq::set_ip_type_of_service (fd_t s_, int iptos)
     }
 #endif
 }
+
+int zmq::set_nosigpipe (fd_t s_)
+{
+#ifdef SO_NOSIGPIPE
+    //  Make sure that SIGPIPE signal is not generated when writing to a
+    //  connection that was already closed by the peer.
+    //  As per POSIX spec, EINVAL will be returned if the socket was valid but
+    //  the connection has been reset by the peer. Return an error so that the
+    //  socket can be closed and the connection retried if necessary.
+    int set = 1;
+    int rc = setsockopt (s_, SOL_SOCKET, SO_NOSIGPIPE, &set, sizeof (int));
+    if (rc != 0 && errno == EINVAL)
+        return -1;
+    errno_assert (rc == 0);
+#else
+    LIBZMQ_UNUSED (s_);
+#endif
+
+    return 0;
+}

src/ip.hpp

@@ -52,6 +52,10 @@ namespace zmq
     // Sets the IP Type-Of-Service for the underlying socket
     void set_ip_type_of_service (fd_t s_, int iptos);
 
+    // Sets the SO_NOSIGPIPE option for the underlying socket.
+    // Return 0 on success, -1 if the connection has been closed by the peer
+    int set_nosigpipe (fd_t s_);
+
 }
 
 #endif

src/ipc_listener.cpp

@@ -418,6 +418,17 @@ zmq::fd_t zmq::ipc_listener_t::accept ()
     }
 #endif
 
+    if (zmq::set_nosigpipe (sock)) {
+#ifdef ZMQ_HAVE_WINDOWS
+        int rc = closesocket (sock);
+        wsa_assert (rc != SOCKET_ERROR);
+#else
+        int rc = ::close (sock);
+        errno_assert (rc == 0);
+#endif
+        return retired_fd;
+    }
+
     return sock;
 }
 

src/stream_engine.cpp

@@ -132,13 +132,6 @@ zmq::stream_engine_t::stream_engine_t (fd_t fd_, const options_t &options_,
     }
 #endif
 
-#ifdef SO_NOSIGPIPE
-    //  Make sure that SIGPIPE signal is not generated when writing to a
-    //  connection that was already closed by the peer.
-    int set = 1;
-    rc = setsockopt (s, SOL_SOCKET, SO_NOSIGPIPE, &set, sizeof (int));
-    errno_assert (rc == 0);
-#endif
     if(options.heartbeat_interval > 0) {
         heartbeat_timeout = options.heartbeat_timeout;
         if(heartbeat_timeout == -1)

src/tcp_listener.cpp

@@ -330,6 +330,17 @@ zmq::fd_t zmq::tcp_listener_t::accept ()
         }
     }
 
+    if (zmq::set_nosigpipe (sock)) {
+#ifdef ZMQ_HAVE_WINDOWS
+        int rc = closesocket (sock);
+        wsa_assert (rc != SOCKET_ERROR);
+#else
+        int rc = ::close (sock);
+        errno_assert (rc == 0);
+#endif
+        return retired_fd;
+    }
+
     // Set the IP Type-Of-Service priority for this client socket
     if (options.tos != 0)
         set_ip_type_of_service (sock, options.tos);