Include socket address in client probe data

It is useful to know where the client is connecting from,
so include the socket address in probe data.

* daemon/libvirtd.h: Use virSocketAddr for storing client
  address and keep printable address handy for logging
* daemon/libvirtd.c: Include socket address in client
  connect/disconnect probes
* daemon/probes.d: Add socket address to probes
* examples/systemtap/client.stp: Print socket address
* src/util/network.h: Add sockaddr_un to virSocketAddr union

daemon/libvirtd.h

@@ -48,6 +48,7 @@
 # include "qemu_protocol.h"
 # include "logging.h"
 # include "threads.h"
+# include "network.h"
 
 # if WITH_DTRACE
 #  ifndef LIBVIRTD_PROBES_H
@@ -61,8 +62,8 @@
         LIBVIRTD_ ## NAME(__VA_ARGS__);                      \
     }
 # else
-#  define PROBE(NAME, FMT, ...)                                 \
-    VIR_DEBUG_INT("trace." __FILE__, __func__, __LINE__,        \
+#  define PROBE(NAME, FMT, ...)                              \
+    VIR_DEBUG_INT("trace." __FILE__, __func__, __LINE__,     \
                   #NAME ": " FMT, __VA_ARGS__);
 # endif
 
@@ -197,8 +198,8 @@ struct qemud_client {
     unsigned int closing :1;
     int domainEventCallbackID[VIR_DOMAIN_EVENT_ID_LAST];
 
-    struct sockaddr_storage addr;
-    socklen_t addrlen;
+    virSocketAddr addr;
+    const char *addrstr;
 
     int type; /* qemud_sock_type */
     gnutls_session_t tlssession;
@@ -252,12 +253,16 @@ struct qemud_client {
 
 struct qemud_socket {
     char *path;
+
+    virSocketAddr addr;
+    const char *addrstr;
+
     int fd;
     int watch;
     int readonly;
     int type; /* qemud_sock_type */
     int auth;
-    int port;
+
     struct qemud_socket *next;
 };