virNetSocketCheckProtocols: Separate out checking family via getaddrinfo()

The virNetSocketCheckProtocols() function is supposed to tell
caller whether IPv4 and/or IPv6 is supported on the system. In
the initial round, it uses getifaddrs() to see if an interface
has IPv4/IPv6 address assigned and then to double check IPv6 it
uses getaddrinfo() to lookup IPv6 loopback address. Separate out
this latter code because it is going to be reused.

Since the original code lived under an #ifdef and the new
function doesn't it is marked as unused - because on some systems
it may be so.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>

diff --git a/src/rpc/virnetsocket.c b/src/rpc/virnetsocket.c
index e3e935460ff02c58b5a577b0b327aafeb0728e42..1a0cf602869a13dc85f462eb24c5e5491069dcc5 100644 (file)
--- a/src/rpc/virnetsocket.c
+++ b/src/rpc/virnetsocket.c
@@ -141,16 +141,49 @@ static int virNetSocketForkDaemon(const char *binary)
 }
 #endif
 
-int virNetSocketCheckProtocols(bool *hasIPv4,
-                               bool *hasIPv6)
+
+static int G_GNUC_UNUSED
+virNetSocketCheckProtocolByLookup(const char *address,
+                                  int family,
+                                  bool *hasFamily)
 {
-#ifdef HAVE_IFADDRS_H
-    struct ifaddrs *ifaddr = NULL, *ifa;
     struct addrinfo hints;
     struct addrinfo *ai = NULL;
     int gaierr;
 
     memset(&hints, 0, sizeof(hints));
+    hints.ai_family = family;
+    hints.ai_flags = AI_PASSIVE | AI_ADDRCONFIG;
+    hints.ai_socktype = SOCK_STREAM;
+
+    if ((gaierr = getaddrinfo(address, NULL, &hints, &ai)) != 0) {
+        *hasFamily = false;
+
+        if (gaierr == EAI_FAMILY ||
+#ifdef EAI_ADDRFAMILY
+            gaierr == EAI_ADDRFAMILY ||
+#endif
+            gaierr == EAI_NONAME) {
+        } else {
+            virReportError(VIR_ERR_INTERNAL_ERROR,
+                           _("Cannot resolve %s address: %s"),
+                           address,
+                           gai_strerror(gaierr));
+            return -1;
+        }
+    } else {
+        *hasFamily = true;
+    }
+
+    freeaddrinfo(ai);
+    return 0;
+}
+
+int virNetSocketCheckProtocols(bool *hasIPv4,
+                               bool *hasIPv6)
+{
+#ifdef HAVE_IFADDRS_H
+    struct ifaddrs *ifaddr = NULL, *ifa;
 
     *hasIPv4 = *hasIPv6 = false;
 
@@ -172,26 +205,9 @@ int virNetSocketCheckProtocols(bool *hasIPv4,
 
     freeifaddrs(ifaddr);
 
-    hints.ai_flags = AI_PASSIVE | AI_ADDRCONFIG;
-    hints.ai_family = AF_INET6;
-    hints.ai_socktype = SOCK_STREAM;
 
-    if ((gaierr = getaddrinfo("::1", NULL, &hints, &ai)) != 0) {
-        if (gaierr == EAI_FAMILY ||
-# ifdef EAI_ADDRFAMILY
-            gaierr == EAI_ADDRFAMILY ||
-# endif
-            gaierr == EAI_NONAME) {
-            *hasIPv6 = false;
-        } else {
-            virReportError(VIR_ERR_INTERNAL_ERROR,
-                           _("Cannot resolve ::1 address: %s"),
-                           gai_strerror(gaierr));
-            return -1;
-        }
-    }
-
-    freeaddrinfo(ai);
+    if (virNetSocketCheckProtocolByLookup("::1", AF_INET6, hasIPv6) < 0)
+        return -1;
 
     VIR_DEBUG("Protocols: v4 %d v6 %d", *hasIPv4, *hasIPv6);