net: Move creation of dnsmasq hosts file to function starting dnsmasq

The hosts file was created in the network definition function. This
patch moves the place the file is being created to the point where
dnsmasq is being started.

src/network/bridge_driver.c

@@ -846,6 +846,8 @@ networkStartDhcpDaemon(virNetworkObjPtr network)
     char *pidfile = NULL;
     int ret = -1;
     dnsmasqContext *dctx = NULL;
+    virNetworkIpDefPtr ipdef;
+    int i;
 
     if (!virNetworkDefGetIpByIndex(network->def, AF_UNSPEC, 0)) {
         /* no IPv6 addresses, so we don't need to run radvd */
@@ -886,6 +888,18 @@ networkStartDhcpDaemon(virNetworkObjPtr network)
     if (ret < 0)
         goto cleanup;
 
+    /* populate dnsmasq hosts file */
+    for (i = 0; (ipdef = virNetworkDefGetIpByIndex(network->def, AF_UNSPEC, i)); i++) {
+        if (VIR_SOCKET_ADDR_IS_FAMILY(&ipdef->address, AF_INET) &&
+            (ipdef->nranges || ipdef->nhosts)) {
+            if (networkBuildDnsmasqHostsfile(dctx, ipdef,
+                                             network->def->dns) < 0)
+                goto cleanup;
+
+            break;
+        }
+    }
+
     ret = dnsmasqSave(dctx);
     if (ret < 0)
         goto cleanup;
@@ -2742,7 +2756,6 @@ static virNetworkPtr networkDefine(virConnectPtr conn, const char *xml) {
     virNetworkObjPtr network = NULL;
     virNetworkPtr ret = NULL;
     int ii;
-    dnsmasqContext* dctx = NULL;
 
     networkDriverLock(driver);
 
@@ -2799,21 +2812,12 @@ static virNetworkPtr networkDefine(virConnectPtr conn, const char *xml) {
         goto cleanup;
     }
 
-    if (ipv4def) {
-        dctx = dnsmasqContextNew(def->name, DNSMASQ_STATE_DIR);
-        if (dctx == NULL ||
-            networkBuildDnsmasqHostsfile(dctx, ipv4def, def->dns) < 0 ||
-            dnsmasqSave(dctx) < 0)
-            goto cleanup;
-    }
-
     VIR_INFO("Defining network '%s'", def->name);
     ret = virGetNetwork(conn, def->name, def->uuid);
 
 cleanup:
     if (freeDef)
        virNetworkDefFree(def);
-    dnsmasqContextFree(dctx);
     if (network)
         virNetworkObjUnlock(network);
     networkDriverUnlock(driver);