tree-wide: add a single version of "static const int one = 1"

All over the place we define local variables for the various sockopts
that take a bool-like "int" value. Sometimes they are const, sometimes
static, sometimes both, sometimes neither.

Let's clean this up, introduce a common const variable "const_int_one"
(as well as one matching "const_int_zero") and use it everywhere, all
acorss the codebase.

4 files changed, 48 insertions, 52 deletions

diff --git a/src/resolve/resolved-dns-scope.c b/src/resolve/resolved-dns-scope.c
index 5ceb954410..57af95c41f 100644
--- a/src/resolve/resolved-dns-scope.c
+++ b/src/resolve/resolved-dns-scope.c
@@ -313,7 +313,6 @@ static int dns_scope_socket(
         _cleanup_close_ int fd = -1;
         union sockaddr_union sa;
         socklen_t salen;
-        static const int one = 1;
         int r, ifindex;
 
         assert(s);
@@ -379,7 +378,7 @@ static int dns_scope_socket(
                 return -errno;
 
         if (type == SOCK_STREAM) {
-                r = setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &one, sizeof(one));
+                r = setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &const_int_one, sizeof(const_int_one));
                 if (r < 0)
                         return -errno;
         }
@@ -402,11 +401,11 @@ static int dns_scope_socket(
                 /* RFC 4795, section 2.5 requires the TTL to be set to 1 */
 
                 if (sa.sa.sa_family == AF_INET) {
-                        r = setsockopt(fd, IPPROTO_IP, IP_TTL, &one, sizeof(one));
+                        r = setsockopt(fd, IPPROTO_IP, IP_TTL, &const_int_one, sizeof(const_int_one));
                         if (r < 0)
                                 return -errno;
                 } else if (sa.sa.sa_family == AF_INET6) {
-                        r = setsockopt(fd, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &one, sizeof(one));
+                        r = setsockopt(fd, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &const_int_one, sizeof(const_int_one));
                         if (r < 0)
                                 return -errno;
                 }
diff --git a/src/resolve/resolved-dns-stub.c b/src/resolve/resolved-dns-stub.c
index 5ddf13081e..5f87a790c6 100644
--- a/src/resolve/resolved-dns-stub.c
+++ b/src/resolve/resolved-dns-stub.c
@@ -392,7 +392,6 @@ static int on_dns_stub_packet(sd_event_source *s, int fd, uint32_t revents, void
 }
 
 static int manager_dns_stub_udp_fd(Manager *m) {
-        static const int one = 1;
         union sockaddr_union sa = {
                 .in.sin_family = AF_INET,
                 .in.sin_port = htobe16(53),
@@ -408,13 +407,13 @@ static int manager_dns_stub_udp_fd(Manager *m) {
         if (fd < 0)
                 return -errno;
 
-        if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof one) < 0)
+        if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &const_int_one, sizeof const_int_one) < 0)
                 return -errno;
 
-        if (setsockopt(fd, IPPROTO_IP, IP_PKTINFO, &one, sizeof one) < 0)
+        if (setsockopt(fd, IPPROTO_IP, IP_PKTINFO, &const_int_one, sizeof const_int_one) < 0)
                 return -errno;
 
-        if (setsockopt(fd, IPPROTO_IP, IP_RECVTTL, &one, sizeof one) < 0)
+        if (setsockopt(fd, IPPROTO_IP, IP_RECVTTL, &const_int_one, sizeof const_int_one) < 0)
                 return -errno;
 
         /* Make sure no traffic from outside the local host can leak to onto this socket */
@@ -479,7 +478,6 @@ static int on_dns_stub_stream(sd_event_source *s, int fd, uint32_t revents, void
 }
 
 static int manager_dns_stub_tcp_fd(Manager *m) {
-        static const int one = 1;
         union sockaddr_union sa = {
                 .in.sin_family = AF_INET,
                 .in.sin_addr.s_addr = htobe32(INADDR_DNS_STUB),
@@ -495,16 +493,16 @@ static int manager_dns_stub_tcp_fd(Manager *m) {
         if (fd < 0)
                 return -errno;
 
-        if (setsockopt(fd, IPPROTO_IP, IP_TTL, &one, sizeof one) < 0)
+        if (setsockopt(fd, IPPROTO_IP, IP_TTL, &const_int_one, sizeof const_int_one) < 0)
                 return -errno;
 
-        if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof one) < 0)
+        if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &const_int_one, sizeof const_int_one) < 0)
                 return -errno;
 
-        if (setsockopt(fd, IPPROTO_IP, IP_PKTINFO, &one, sizeof one) < 0)
+        if (setsockopt(fd, IPPROTO_IP, IP_PKTINFO, &const_int_one, sizeof const_int_one) < 0)
                 return -errno;
 
-        if (setsockopt(fd, IPPROTO_IP, IP_RECVTTL, &one, sizeof one) < 0)
+        if (setsockopt(fd, IPPROTO_IP, IP_RECVTTL, &const_int_one, sizeof const_int_one) < 0)
                 return -errno;
 
         /* Make sure no traffic from outside the local host can leak to onto this socket */
diff --git a/src/resolve/resolved-llmnr.c b/src/resolve/resolved-llmnr.c
index 2f2a1a15ec..a6100c3b00 100644
--- a/src/resolve/resolved-llmnr.c
+++ b/src/resolve/resolved-llmnr.c
@@ -115,7 +115,7 @@ int manager_llmnr_ipv4_udp_fd(Manager *m) {
                 .in.sin_family = AF_INET,
                 .in.sin_port = htobe16(LLMNR_PORT),
         };
-        static const int one = 1, pmtu = IP_PMTUDISC_DONT, ttl = 255;
+        static const int pmtu = IP_PMTUDISC_DONT, ttl = 255;
         int r;
 
         assert(m);
@@ -140,19 +140,19 @@ int manager_llmnr_ipv4_udp_fd(Manager *m) {
                 goto fail;
         }
 
-        r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_MULTICAST_LOOP, &one, sizeof(one));
+        r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_MULTICAST_LOOP, &const_int_one, sizeof(const_int_one));
         if (r < 0) {
                 r = log_error_errno(errno, "LLMNR-IPv4(UDP): Failed to set IP_MULTICAST_LOOP: %m");
                 goto fail;
         }
 
-        r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_PKTINFO, &one, sizeof(one));
+        r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_PKTINFO, &const_int_one, sizeof(const_int_one));
         if (r < 0) {
                 r = log_error_errno(errno, "LLMNR-IPv4(UDP): Failed to set IP_PKTINFO: %m");
                 goto fail;
         }
 
-        r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_RECVTTL, &one, sizeof(one));
+        r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_RECVTTL, &const_int_one, sizeof(const_int_one));
         if (r < 0) {
                 r = log_error_errno(errno, "LLMNR-IPv4(UDP): Failed to set IP_RECVTTL: %m");
                 goto fail;
@@ -176,7 +176,7 @@ int manager_llmnr_ipv4_udp_fd(Manager *m) {
                 log_warning("LLMNR-IPv4(UDP): There appears to be another LLMNR responder running, or previously systemd-resolved crashed with some outstanding transfers.");
 
                 /* try again with SO_REUSEADDR */
-                r = setsockopt(m->llmnr_ipv4_udp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
+                r = setsockopt(m->llmnr_ipv4_udp_fd, SOL_SOCKET, SO_REUSEADDR, &const_int_one, sizeof(const_int_one));
                 if (r < 0) {
                         r = log_error_errno(errno, "LLMNR-IPv4(UDP): Failed to set SO_REUSEADDR: %m");
                         goto fail;
@@ -189,7 +189,7 @@ int manager_llmnr_ipv4_udp_fd(Manager *m) {
                 }
         } else {
                 /* enable SO_REUSEADDR for the case that the user really wants multiple LLMNR responders */
-                r = setsockopt(m->llmnr_ipv4_udp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
+                r = setsockopt(m->llmnr_ipv4_udp_fd, SOL_SOCKET, SO_REUSEADDR, &const_int_one, sizeof(const_int_one));
                 if (r < 0) {
                         r = log_error_errno(errno, "LLMNR-IPv4(UDP): Failed to set SO_REUSEADDR: %m");
                         goto fail;
@@ -214,7 +214,7 @@ int manager_llmnr_ipv6_udp_fd(Manager *m) {
                 .in6.sin6_family = AF_INET6,
                 .in6.sin6_port = htobe16(LLMNR_PORT),
         };
-        static const int one = 1, ttl = 255;
+        static const int ttl = 255;
         int r;
 
         assert(m);
@@ -239,25 +239,25 @@ int manager_llmnr_ipv6_udp_fd(Manager *m) {
                 goto fail;
         }
 
-        r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &one, sizeof(one));
+        r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &const_int_one, sizeof(const_int_one));
         if (r < 0) {
                 r = log_error_errno(errno, "LLMNR-IPv6(UDP): Failed to set IPV6_MULTICAST_LOOP: %m");
                 goto fail;
         }
 
-        r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_V6ONLY, &one, sizeof(one));
+        r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_V6ONLY, &const_int_one, sizeof(const_int_one));
         if (r < 0) {
                 r = log_error_errno(errno, "LLMNR-IPv6(UDP): Failed to set IPV6_V6ONLY: %m");
                 goto fail;
         }
 
-        r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &one, sizeof(one));
+        r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &const_int_one, sizeof(const_int_one));
         if (r < 0) {
                 r = log_error_errno(errno, "LLMNR-IPv6(UDP): Failed to set IPV6_RECVPKTINFO: %m");
                 goto fail;
         }
 
-        r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &one, sizeof(one));
+        r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &const_int_one, sizeof(const_int_one));
         if (r < 0) {
                 r = log_error_errno(errno, "LLMNR-IPv6(UDP): Failed to set IPV6_RECVHOPLIMIT: %m");
                 goto fail;
@@ -274,7 +274,7 @@ int manager_llmnr_ipv6_udp_fd(Manager *m) {
                 log_warning("LLMNR-IPv6(UDP): There appears to be another LLMNR responder running, or previously systemd-resolved crashed with some outstanding transfers.");
 
                 /* try again with SO_REUSEADDR */
-                r = setsockopt(m->llmnr_ipv6_udp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
+                r = setsockopt(m->llmnr_ipv6_udp_fd, SOL_SOCKET, SO_REUSEADDR, &const_int_one, sizeof(const_int_one));
                 if (r < 0) {
                         r = log_error_errno(errno, "LLMNR-IPv6(UDP): Failed to set SO_REUSEADDR: %m");
                         goto fail;
@@ -287,7 +287,7 @@ int manager_llmnr_ipv6_udp_fd(Manager *m) {
                 }
         } else {
                 /* enable SO_REUSEADDR for the case that the user really wants multiple LLMNR responders */
-                r = setsockopt(m->llmnr_ipv6_udp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
+                r = setsockopt(m->llmnr_ipv6_udp_fd, SOL_SOCKET, SO_REUSEADDR, &const_int_one, sizeof(const_int_one));
                 if (r < 0) {
                         r = log_error_errno(errno, "LLMNR-IPv6(UDP): Failed to set SO_REUSEADDR: %m");
                         goto fail;
@@ -355,7 +355,7 @@ int manager_llmnr_ipv4_tcp_fd(Manager *m) {
                 .in.sin_family = AF_INET,
                 .in.sin_port = htobe16(LLMNR_PORT),
         };
-        static const int one = 1, pmtu = IP_PMTUDISC_DONT;
+        static const int pmtu = IP_PMTUDISC_DONT;
         int r;
 
         assert(m);
@@ -368,19 +368,19 @@ int manager_llmnr_ipv4_tcp_fd(Manager *m) {
                 return log_error_errno(errno, "LLMNR-IPv4(TCP): Failed to create socket: %m");
 
         /* RFC 4795, section 2.5. requires setting the TTL of TCP streams to 1 */
-        r = setsockopt(m->llmnr_ipv4_tcp_fd, IPPROTO_IP, IP_TTL, &one, sizeof(one));
+        r = setsockopt(m->llmnr_ipv4_tcp_fd, IPPROTO_IP, IP_TTL, &const_int_one, sizeof(const_int_one));
         if (r < 0) {
                 r = log_error_errno(errno, "LLMNR-IPv4(TCP): Failed to set IP_TTL: %m");
                 goto fail;
         }
 
-        r = setsockopt(m->llmnr_ipv4_tcp_fd, IPPROTO_IP, IP_PKTINFO, &one, sizeof(one));
+        r = setsockopt(m->llmnr_ipv4_tcp_fd, IPPROTO_IP, IP_PKTINFO, &const_int_one, sizeof(const_int_one));
         if (r < 0) {
                 r = log_error_errno(errno, "LLMNR-IPv4(TCP): Failed to set IP_PKTINFO: %m");
                 goto fail;
         }
 
-        r = setsockopt(m->llmnr_ipv4_tcp_fd, IPPROTO_IP, IP_RECVTTL, &one, sizeof(one));
+        r = setsockopt(m->llmnr_ipv4_tcp_fd, IPPROTO_IP, IP_RECVTTL, &const_int_one, sizeof(const_int_one));
         if (r < 0) {
                 r = log_error_errno(errno, "LLMNR-IPv4(TCP): Failed to set IP_RECVTTL: %m");
                 goto fail;
@@ -404,7 +404,7 @@ int manager_llmnr_ipv4_tcp_fd(Manager *m) {
                 log_warning("LLMNR-IPv4(TCP): There appears to be another LLMNR responder running, or previously systemd-resolved crashed with some outstanding transfers.");
 
                 /* try again with SO_REUSEADDR */
-                r = setsockopt(m->llmnr_ipv4_tcp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
+                r = setsockopt(m->llmnr_ipv4_tcp_fd, SOL_SOCKET, SO_REUSEADDR, &const_int_one, sizeof(const_int_one));
                 if (r < 0) {
                         r = log_error_errno(errno, "LLMNR-IPv4(TCP): Failed to set SO_REUSEADDR: %m");
                         goto fail;
@@ -417,7 +417,7 @@ int manager_llmnr_ipv4_tcp_fd(Manager *m) {
                 }
         } else {
                 /* enable SO_REUSEADDR for the case that the user really wants multiple LLMNR responders */
-                r = setsockopt(m->llmnr_ipv4_tcp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
+                r = setsockopt(m->llmnr_ipv4_tcp_fd, SOL_SOCKET, SO_REUSEADDR, &const_int_one, sizeof(const_int_one));
                 if (r < 0) {
                         r = log_error_errno(errno, "LLMNR-IPv4(TCP): Failed to set SO_REUSEADDR: %m");
                         goto fail;
@@ -448,7 +448,6 @@ int manager_llmnr_ipv6_tcp_fd(Manager *m) {
                 .in6.sin6_family = AF_INET6,
                 .in6.sin6_port = htobe16(LLMNR_PORT),
         };
-        static const int one = 1;
         int r;
 
         assert(m);
@@ -461,25 +460,25 @@ int manager_llmnr_ipv6_tcp_fd(Manager *m) {
                 return log_error_errno(errno, "LLMNR-IPv6(TCP): Failed to create socket: %m");
 
         /* RFC 4795, section 2.5. requires setting the TTL of TCP streams to 1 */
-        r = setsockopt(m->llmnr_ipv6_tcp_fd, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &one, sizeof(one));
+        r = setsockopt(m->llmnr_ipv6_tcp_fd, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &const_int_one, sizeof(const_int_one));
         if (r < 0) {
                 r = log_error_errno(errno, "LLMNR-IPv6(TCP): Failed to set IPV6_UNICAST_HOPS: %m");
                 goto fail;
         }
 
-        r = setsockopt(m->llmnr_ipv6_tcp_fd, IPPROTO_IPV6, IPV6_V6ONLY, &one, sizeof(one));
+        r = setsockopt(m->llmnr_ipv6_tcp_fd, IPPROTO_IPV6, IPV6_V6ONLY, &const_int_one, sizeof(const_int_one));
         if (r < 0) {
                 r = log_error_errno(errno, "LLMNR-IPv6(TCP): Failed to set IPV6_V6ONLY: %m");
                 goto fail;
         }
 
-        r = setsockopt(m->llmnr_ipv6_tcp_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &one, sizeof(one));
+        r = setsockopt(m->llmnr_ipv6_tcp_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &const_int_one, sizeof(const_int_one));
         if (r < 0) {
                 r = log_error_errno(errno, "LLMNR-IPv6(TCP): Failed to set IPV6_RECVPKTINFO: %m");
                 goto fail;
         }
 
-        r = setsockopt(m->llmnr_ipv6_tcp_fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &one, sizeof(one));
+        r = setsockopt(m->llmnr_ipv6_tcp_fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &const_int_one, sizeof(const_int_one));
         if (r < 0) {
                 r = log_error_errno(errno, "LLMNR-IPv6(TCP): Failed to set IPV6_RECVHOPLIMIT: %m");
                 goto fail;
@@ -496,7 +495,7 @@ int manager_llmnr_ipv6_tcp_fd(Manager *m) {
                 log_warning("LLMNR-IPv6(TCP): There appears to be another LLMNR responder running, or previously systemd-resolved crashed with some outstanding transfers.");
 
                 /* try again with SO_REUSEADDR */
-                r = setsockopt(m->llmnr_ipv6_tcp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
+                r = setsockopt(m->llmnr_ipv6_tcp_fd, SOL_SOCKET, SO_REUSEADDR, &const_int_one, sizeof(const_int_one));
                 if (r < 0) {
                         r = log_error_errno(errno, "LLMNR-IPv6(TCP): Failed to set SO_REUSEADDR: %m");
                         goto fail;
@@ -509,7 +508,7 @@ int manager_llmnr_ipv6_tcp_fd(Manager *m) {
                 }
         } else {
                 /* enable SO_REUSEADDR for the case that the user really wants multiple LLMNR responders */
-                r = setsockopt(m->llmnr_ipv6_tcp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
+                r = setsockopt(m->llmnr_ipv6_tcp_fd, SOL_SOCKET, SO_REUSEADDR, &const_int_one, sizeof(const_int_one));
                 if (r < 0) {
                         r = log_error_errno(errno, "LLMNR-IPv6(TCP): Failed to set SO_REUSEADDR: %m");
                         goto fail;
diff --git a/src/resolve/resolved-mdns.c b/src/resolve/resolved-mdns.c
index e70138181a..be258b0e85 100644
--- a/src/resolve/resolved-mdns.c
+++ b/src/resolve/resolved-mdns.c
@@ -344,7 +344,7 @@ int manager_mdns_ipv4_fd(Manager *m) {
                 .in.sin_family = AF_INET,
                 .in.sin_port = htobe16(MDNS_PORT),
         };
-        static const int one = 1, pmtu = IP_PMTUDISC_DONT, ttl = 255;
+        static const int pmtu = IP_PMTUDISC_DONT, ttl = 255;
         int r;
 
         assert(m);
@@ -368,19 +368,19 @@ int manager_mdns_ipv4_fd(Manager *m) {
                 goto fail;
         }
 
-        r = setsockopt(m->mdns_ipv4_fd, IPPROTO_IP, IP_MULTICAST_LOOP, &one, sizeof(one));
+        r = setsockopt(m->mdns_ipv4_fd, IPPROTO_IP, IP_MULTICAST_LOOP, &const_int_one, sizeof(const_int_one));
         if (r < 0) {
                 r = log_error_errno(errno, "mDNS-IPv4: Failed to set IP_MULTICAST_LOOP: %m");
                 goto fail;
         }
 
-        r = setsockopt(m->mdns_ipv4_fd, IPPROTO_IP, IP_PKTINFO, &one, sizeof(one));
+        r = setsockopt(m->mdns_ipv4_fd, IPPROTO_IP, IP_PKTINFO, &const_int_one, sizeof(const_int_one));
         if (r < 0) {
                 r = log_error_errno(errno, "mDNS-IPv4: Failed to set IP_PKTINFO: %m");
                 goto fail;
         }
 
-        r = setsockopt(m->mdns_ipv4_fd, IPPROTO_IP, IP_RECVTTL, &one, sizeof(one));
+        r = setsockopt(m->mdns_ipv4_fd, IPPROTO_IP, IP_RECVTTL, &const_int_one, sizeof(const_int_one));
         if (r < 0) {
                 r = log_error_errno(errno, "mDNS-IPv4: Failed to set IP_RECVTTL: %m");
                 goto fail;
@@ -405,7 +405,7 @@ int manager_mdns_ipv4_fd(Manager *m) {
                 log_warning("mDNS-IPv4: There appears to be another mDNS responder running, or previously systemd-resolved crashed with some outstanding transfers.");
 
                 /* try again with SO_REUSEADDR */
-                r = setsockopt(m->mdns_ipv4_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
+                r = setsockopt(m->mdns_ipv4_fd, SOL_SOCKET, SO_REUSEADDR, &const_int_one, sizeof(const_int_one));
                 if (r < 0) {
                         r = log_error_errno(errno, "mDNS-IPv4: Failed to set SO_REUSEADDR: %m");
                         goto fail;
@@ -418,7 +418,7 @@ int manager_mdns_ipv4_fd(Manager *m) {
                 }
         } else {
                 /* enable SO_REUSEADDR for the case that the user really wants multiple mDNS responders */
-                r = setsockopt(m->mdns_ipv4_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
+                r = setsockopt(m->mdns_ipv4_fd, SOL_SOCKET, SO_REUSEADDR, &const_int_one, sizeof(const_int_one));
                 if (r < 0) {
                         r = log_error_errno(errno, "mDNS-IPv4: Failed to set SO_REUSEADDR: %m");
                         goto fail;
@@ -441,7 +441,7 @@ int manager_mdns_ipv6_fd(Manager *m) {
                 .in6.sin6_family = AF_INET6,
                 .in6.sin6_port = htobe16(MDNS_PORT),
         };
-        static const int one = 1, ttl = 255;
+        static const int ttl = 255;
         int r;
 
         assert(m);
@@ -466,25 +466,25 @@ int manager_mdns_ipv6_fd(Manager *m) {
                 goto fail;
         }
 
-        r = setsockopt(m->mdns_ipv6_fd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &one, sizeof(one));
+        r = setsockopt(m->mdns_ipv6_fd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &const_int_one, sizeof(const_int_one));
         if (r < 0) {
                 r = log_error_errno(errno, "mDNS-IPv6: Failed to set IPV6_MULTICAST_LOOP: %m");
                 goto fail;
         }
 
-        r = setsockopt(m->mdns_ipv6_fd, IPPROTO_IPV6, IPV6_V6ONLY, &one, sizeof(one));
+        r = setsockopt(m->mdns_ipv6_fd, IPPROTO_IPV6, IPV6_V6ONLY, &const_int_one, sizeof(const_int_one));
         if (r < 0) {
                 r = log_error_errno(errno, "mDNS-IPv6: Failed to set IPV6_V6ONLY: %m");
                 goto fail;
         }
 
-        r = setsockopt(m->mdns_ipv6_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &one, sizeof(one));
+        r = setsockopt(m->mdns_ipv6_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &const_int_one, sizeof(const_int_one));
         if (r < 0) {
                 r = log_error_errno(errno, "mDNS-IPv6: Failed to set IPV6_RECVPKTINFO: %m");
                 goto fail;
         }
 
-        r = setsockopt(m->mdns_ipv6_fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &one, sizeof(one));
+        r = setsockopt(m->mdns_ipv6_fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &const_int_one, sizeof(const_int_one));
         if (r < 0) {
                 r = log_error_errno(errno, "mDNS-IPv6: Failed to set IPV6_RECVHOPLIMIT: %m");
                 goto fail;
@@ -502,7 +502,7 @@ int manager_mdns_ipv6_fd(Manager *m) {
                 log_warning("mDNS-IPv6: There appears to be another mDNS responder running, or previously systemd-resolved crashed with some outstanding transfers.");
 
                 /* try again with SO_REUSEADDR */
-                r = setsockopt(m->mdns_ipv6_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
+                r = setsockopt(m->mdns_ipv6_fd, SOL_SOCKET, SO_REUSEADDR, &const_int_one, sizeof(const_int_one));
                 if (r < 0) {
                         r = log_error_errno(errno, "mDNS-IPv6: Failed to set SO_REUSEADDR: %m");
                         goto fail;
@@ -515,7 +515,7 @@ int manager_mdns_ipv6_fd(Manager *m) {
                 }
         } else {
                 /* enable SO_REUSEADDR for the case that the user really wants multiple mDNS responders */
-                r = setsockopt(m->mdns_ipv6_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
+                r = setsockopt(m->mdns_ipv6_fd, SOL_SOCKET, SO_REUSEADDR, &const_int_one, sizeof(const_int_one));
                 if (r < 0) {
                         r = log_error_errno(errno, "mDNS-IPv6: Failed to set SO_REUSEADDR: %m");
                         goto fail;