resolved: cache formatted server string in DnsServer structure

This makes it easier to log information about a specific DnsServer object.

4 files changed, 28 insertions, 28 deletions

diff --git a/src/resolve/resolved-dns-server.c b/src/resolve/resolved-dns-server.c
index 3baf63ffa7..dcfef66d4c 100644
--- a/src/resolve/resolved-dns-server.c
+++ b/src/resolve/resolved-dns-server.c
@@ -135,6 +135,7 @@ DnsServer* dns_server_unref(DnsServer *s)  {
         if (s->n_ref > 0)
                 return NULL;
 
+        free(s->server_string);
         free(s);
         return NULL;
 }
@@ -316,12 +317,10 @@ void dns_server_packet_truncated(DnsServer *s, DnsServerFeatureLevel level) {
 }
 
 void dns_server_packet_rrsig_missing(DnsServer *s) {
-        _cleanup_free_ char *ip = NULL;
         assert(s);
         assert(s->manager);
 
-        in_addr_to_string(s->family, &s->address, &ip);
-        log_warning("DNS server %s does not augment replies with RRSIG records, DNSSEC not available.", strna(ip));
+        log_warning("DNS server %s does not augment replies with RRSIG records, DNSSEC not available.", dns_server_string(s));
 
         s->rrsig_missing = true;
 }
@@ -350,7 +349,6 @@ DnsServerFeatureLevel dns_server_possible_feature_level(DnsServer *s) {
 
         if (s->possible_feature_level != DNS_SERVER_FEATURE_LEVEL_BEST &&
             dns_server_grace_period_expired(s)) {
-                _cleanup_free_ char *ip = NULL;
 
                 s->possible_feature_level = DNS_SERVER_FEATURE_LEVEL_BEST;
                 s->n_failed_udp = 0;
@@ -360,9 +358,9 @@ DnsServerFeatureLevel dns_server_possible_feature_level(DnsServer *s) {
                 s->verified_usec = 0;
                 s->rrsig_missing = false;
 
-                in_addr_to_string(s->family, &s->address, &ip);
                 log_info("Grace period over, resuming full feature set (%s) for DNS server %s",
-                         dns_server_feature_level_to_string(s->possible_feature_level), strna(ip));
+                         dns_server_feature_level_to_string(s->possible_feature_level),
+                         dns_server_string(s));
 
         } else if (s->possible_feature_level <= s->verified_feature_level)
                 s->possible_feature_level = s->verified_feature_level;
@@ -405,7 +403,6 @@ DnsServerFeatureLevel dns_server_possible_feature_level(DnsServer *s) {
                         s->possible_feature_level--;
 
                 if (p != s->possible_feature_level) {
-                        _cleanup_free_ char *ip = NULL;
 
                         /* We changed the feature level, reset the counting */
                         s->n_failed_udp = 0;
@@ -414,9 +411,9 @@ DnsServerFeatureLevel dns_server_possible_feature_level(DnsServer *s) {
                         s->packet_truncated = false;
                         s->verified_usec = 0;
 
-                        in_addr_to_string(s->family, &s->address, &ip);
                         log_warning("Using degraded feature set (%s) for DNS server %s",
-                                    dns_server_feature_level_to_string(s->possible_feature_level), strna(ip));
+                                    dns_server_feature_level_to_string(s->possible_feature_level),
+                                    dns_server_string(s));
                 }
         }
 
@@ -451,6 +448,15 @@ int dns_server_adjust_opt(DnsServer *server, DnsPacket *packet, DnsServerFeature
         return dns_packet_append_opt(packet, packet_size, edns_do, NULL);
 }
 
+const char *dns_server_string(DnsServer *server) {
+        assert(server);
+
+        if (!server->server_string)
+                (void) in_addr_to_string(server->family, &server->address, &server->server_string);
+
+        return strna(server->server_string);
+}
+
 static void dns_server_hash_func(const void *p, struct siphash *state) {
         const DnsServer *s = p;
 
@@ -542,12 +548,8 @@ DnsServer *manager_set_dns_server(Manager *m, DnsServer *s) {
         if (m->current_dns_server == s)
                 return s;
 
-        if (s) {
-                _cleanup_free_ char *ip = NULL;
-
-                in_addr_to_string(s->family, &s->address, &ip);
-                log_info("Switching to system DNS server %s.", strna(ip));
-        }
+        if (s)
+                log_info("Switching to system DNS server %s.", dns_server_string(s));
 
         dns_server_unref(m->current_dns_server);
         m->current_dns_server = dns_server_ref(s);
diff --git a/src/resolve/resolved-dns-server.h b/src/resolve/resolved-dns-server.h
index 3ad6a0d38f..faa22babb5 100644
--- a/src/resolve/resolved-dns-server.h
+++ b/src/resolve/resolved-dns-server.h
@@ -61,6 +61,8 @@ struct DnsServer {
         int family;
         union in_addr_union address;
 
+        char *server_string;
+
         usec_t resend_timeout;
         usec_t max_rtt;
 
@@ -112,6 +114,8 @@ DnsServerFeatureLevel dns_server_possible_feature_level(DnsServer *s);
 
 int dns_server_adjust_opt(DnsServer *server, DnsPacket *packet, DnsServerFeatureLevel level);
 
+const char *dns_server_string(DnsServer *server);
+
 DnsServer *dns_server_find(DnsServer *first, int family, const union in_addr_union *in_addr);
 
 void dns_server_unlink_all(DnsServer *first);
diff --git a/src/resolve/resolved-link.c b/src/resolve/resolved-link.c
index 30838ef8cc..928307e004 100644
--- a/src/resolve/resolved-link.c
+++ b/src/resolve/resolved-link.c
@@ -463,12 +463,8 @@ DnsServer* link_set_dns_server(Link *l, DnsServer *s) {
         if (l->current_dns_server == s)
                 return s;
 
-        if (s) {
-                _cleanup_free_ char *ip = NULL;
-
-                in_addr_to_string(s->family, &s->address, &ip);
-                log_info("Switching to DNS server %s for interface %s.", strna(ip), l->name);
-        }
+        if (s)
+                log_info("Switching to DNS server %s for interface %s.", dns_server_string(s), l->name);
 
         dns_server_unref(l->current_dns_server);
         l->current_dns_server = dns_server_ref(s);
diff --git a/src/resolve/resolved-resolv-conf.c b/src/resolve/resolved-resolv-conf.c
index 956f380f3c..7567f4c369 100644
--- a/src/resolve/resolved-resolv-conf.c
+++ b/src/resolve/resolved-resolv-conf.c
@@ -147,16 +147,14 @@ clear:
 }
 
 static void write_resolv_conf_server(DnsServer *s, FILE *f, unsigned *count) {
-        _cleanup_free_ char *t  = NULL;
-        int r;
-
         assert(s);
         assert(f);
         assert(count);
 
-        r = in_addr_to_string(s->family, &s->address, &t);
-        if (r < 0) {
-                log_warning_errno(r, "Invalid DNS address. Ignoring: %m");
+        (void) dns_server_string(s);
+
+        if (!s->server_string) {
+                log_warning("Our of memory, or invalid DNS address. Ignoring server.");
                 return;
         }
 
@@ -164,7 +162,7 @@ static void write_resolv_conf_server(DnsServer *s, FILE *f, unsigned *count) {
                 fputs("# Too many DNS servers configured, the following entries may be ignored.\n", f);
         (*count) ++;
 
-        fprintf(f, "nameserver %s\n", t);
+        fprintf(f, "nameserver %s\n", s->server_string);
 }
 
 static void write_resolv_conf_search(