udp_send.c: Send EOF packet only once.

Currently this can be sent many times, which is pointless and might
confuse clients. This patch adds a bool member to struct udp_target
to keep track whether the EOF packet has been sent.

diff --git a/udp_send.c b/udp_send.c
index bbc38f0117d796ac5211bf86821244daf17baf84..425118a135edfee7224f40256dc087a803115aaf 100644 (file)
--- a/udp_send.c
+++ b/udp_send.c
@@ -46,6 +46,8 @@ struct udp_target {
        struct fec_client *fc;
        /** The FEC parameters for this target. */
        struct fec_client_parms fcp;
+       /** Whether we already sent the FEC eof packet to this target. */
+       bool sent_fec_eof;
 };
 
 static struct list_head targets;
@@ -54,15 +56,16 @@ static int sender_status;
 static void udp_close_target(struct sender_client *sc)
 {
        const char *buf;
-       size_t len = vss_get_fec_eof_packet(&buf);
-
-       /*
-        * Ignore the return value of write() since we are closing the target
-        * anyway. The sole purpose of the "do_nothing" statement is to silence
-        * gcc.
-        */
-       if (write(sc->fd, buf, len))
-               do_nothing;
+       size_t len;
+       struct udp_target *ut = sc->private_data;
+
+       if (ut->sent_fec_eof)
+               return;
+       PARA_NOTICE_LOG("sending FEC EOF\n");
+       len = vss_get_fec_eof_packet(&buf);
+       /* Ignore write() errors since we are closing the target anyway. */
+       if (write(sc->fd, buf, len) == len)
+               ut->sent_fec_eof = true;
 }
 
 static void udp_delete_target(struct sender_client *sc, const char *msg)
@@ -232,9 +235,11 @@ static int udp_com_delete(struct sender_command_data *scd)
 /** Initialize UDP session and set maximum payload size. */
 static int udp_init_fec(struct sender_client *sc)
 {
+       struct udp_target *ut = sc->private_data;
        int mps;
 
        PARA_NOTICE_LOG("sending to udp %s\n", sc->name);
+       ut->sent_fec_eof = false;
        mps = generic_max_transport_msg_size(sc->fd) - sizeof(struct udphdr);
        PARA_INFO_LOG("current MPS = %d bytes\n", mps);
        return mps;