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

[John Ferlan]

On 05/19/2017 07:43 AM, Ján Tomko wrote:
> 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 = "";

I believe port should be "0" instead of ""

Also, it seems connectHost could be NULL too, how does that affect the
qemuMonitorJSONBuildInetSocketAddress a few lines earlier?

FWIW: Questions are from reading the qemuBuildChrChardevStr /
qemuBuildChrArgStr code and the libxl_conf.c implementation...


ACK, if you fix or shall I say...

Reviewed-by: John Ferlan <jferlan at redhat.com>

and IDC if that's added to the committed code (it's my attempt to
conform to something new, AKA teach an old dog new tricks).


John

> +            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";
>