[libvirt] [PATCH] qemu: handle missing bind host/service on chardev hotplug

[Ján Tomko]

On domain startup, bind host or bind service can be omitted
and we will format a working command line.

Extend this to hotplug as well and specify the service to QEMU
even if the host is missing.

https://bugzilla.redhat.com/show_bug.cgi?id=1452441
---
 src/qemu/qemu_monitor_json.c | 13 ++++++++++---
 tests/qemumonitorjsontest.c  | 11 +++++++++++
 2 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/src/qemu/qemu_monitor_json.c b/src/qemu/qemu_monitor_json.c
index 0837290..ca9bb14 100644
--- a/src/qemu/qemu_monitor_json.c
+++ b/src/qemu/qemu_monitor_json.c
@@ -6429,6 +6429,8 @@ qemuMonitorJSONAttachCharDevCommand(const char *chrID,
     virJSONValuePtr data = NULL;
     virJSONValuePtr addr = NULL;
     const char *backend_type = NULL;
+    const char *host;
+    const char *port;
     char *tlsalias = NULL;
     bool telnet;
 
@@ -6492,9 +6494,14 @@ qemuMonitorJSONAttachCharDevCommand(const char *chrID,
             virJSONValueObjectAppend(data, "remote", addr) < 0)
             goto error;
 
-        if (chr->data.udp.bindHost) {
-            addr = qemuMonitorJSONBuildInetSocketAddress(chr->data.udp.bindHost,
-                                                         chr->data.udp.bindService);
+        host = chr->data.udp.bindHost;
+        port = chr->data.udp.bindService;
+        if (host || port) {
+            if (!host)
+                host = "";
+            if (!port)
+                port = "";
+            addr = qemuMonitorJSONBuildInetSocketAddress(host, port);
             if (!addr ||
                 virJSONValueObjectAppend(data, "local", addr) < 0)
                 goto error;
diff --git a/tests/qemumonitorjsontest.c b/tests/qemumonitorjsontest.c
index e9f9d47..3de901c 100644
--- a/tests/qemumonitorjsontest.c
+++ b/tests/qemumonitorjsontest.c
@@ -895,6 +895,17 @@ qemuMonitorJSONTestAttachChardev(virDomainXMLOptionPtr xmlopt)
                                        "'data':{'host':'localhost',"
                                                "'port':'4321'}}}}}");
 
+    chr.data.udp.bindHost = NULL;
+    chr.data.udp.bindService = (char *) "4321";
+    CHECK("udp", false,
+          "{'id':'alias',"
+           "'backend':{'type':'udp',"
+                      "'data':{'remote':{'type':'inet',"
+                                        "'data':{'host':'example.com',"
+                                                "'port':'1234'}},"
+                              "'local':{'type':'inet',"
+                                       "'data':{'host':'',"
+                                               "'port':'4321'}}}}}");
     memset(&chr, 0, sizeof(chr));
     chr.type = VIR_DOMAIN_CHR_TYPE_UNIX;
     chr.data.nix.path = (char *) "/path/to/socket";
-- 
2.10.2