maint: define a macro for IPv4 loopback address

Use a macro instead of hardcoding "127.0.0.1" throughout the
sources.

src/internal.h

@@ -79,6 +79,8 @@
 #  define INET_ADDRSTRLEN 16
 # endif
 
+# define VIR_LOOPBACK_IPV4_ADDR "127.0.0.1"
+
 /* String equality tests, suggested by Jim Meyering. */
 # define STREQ(a, b) (strcmp(a, b) == 0)
 # define STRCASEEQ(a, b) (c_strcasecmp(a, b) == 0)

src/qemu/qemu_conf.c

@@ -250,10 +250,10 @@ virQEMUDriverConfigPtr virQEMUDriverConfigNew(bool privileged)
                    SYSCONFDIR "/pki/qemu") < 0)
         goto error;
 
-    if (VIR_STRDUP(cfg->vncListen, "127.0.0.1") < 0)
+    if (VIR_STRDUP(cfg->vncListen, VIR_LOOPBACK_IPV4_ADDR) < 0)
         goto error;
 
-    if (VIR_STRDUP(cfg->spiceListen, "127.0.0.1") < 0)
+    if (VIR_STRDUP(cfg->spiceListen, VIR_LOOPBACK_IPV4_ADDR) < 0)
         goto error;
 
     /*

src/util/virsocketaddr.c

@@ -383,11 +383,11 @@ virSocketAddrFormatFull(const virSocketAddr *addr,
      * nicely for UNIX sockets */
     if (addr->data.sa.sa_family == AF_UNIX) {
         if (withService) {
-            if (virAsprintf(&addrstr, "127.0.0.1%s0",
+            if (virAsprintf(&addrstr, VIR_LOOPBACK_IPV4_ADDR"%s0",
                             separator ? separator : ":") < 0)
                 goto error;
         } else {
-            if (VIR_STRDUP(addrstr, "127.0.0.1") < 0)
+            if (VIR_STRDUP(addrstr, VIR_LOOPBACK_IPV4_ADDR) < 0)
                 goto error;
         }
         return addrstr;

src/vz/vz_sdk.c

@@ -3084,7 +3084,7 @@ static int prlsdkApplyGraphicsParams(PRL_HANDLE sdkdom,
 
     glisten = virDomainGraphicsGetListen(gr, 0);
     pret = PrlVmCfg_SetVNCHostName(sdkdom, glisten && glisten->address ?
-                                           glisten->address : "127.0.0.1");
+                                           glisten->address : VIR_LOOPBACK_IPV4_ADDR);
     prlsdkCheckRetGoto(pret, cleanup);
 
     ret = 0;