resolved: make packet flags logic more expressive again

This partially reverts 106784ebb7b303ae471851100a773ad2aebf5b80, ad
readds separate DNS_PACKET_MAKE_FLAGS() invocations for the LLMNR and
DNS case. This is important since SOme flags have different names and
meanings on LLMNR and on DNS and we should clarify that via the comments
and how we put things together.

diff --git a/src/resolve/resolved-dns-packet.c b/src/resolve/resolved-dns-packet.c
index 784d949ccea68ad0ed93dacc2da48559d294384c..bebd1ee4a6e55f64d32ddd80c496d2b520769bdb 100644 (file)
--- a/src/resolve/resolved-dns-packet.c
+++ b/src/resolve/resolved-dns-packet.c
@@ -64,7 +64,7 @@ int dns_packet_new(DnsPacket **ret, DnsProtocol protocol, size_t mtu) {
 int dns_packet_new_query(DnsPacket **ret, DnsProtocol protocol, size_t mtu) {
         DnsPacket *p;
         DnsPacketHeader *h;
-        int r, rd;
+        int r;
 
         assert(ret);
 
@@ -74,27 +74,26 @@ int dns_packet_new_query(DnsPacket **ret, DnsProtocol protocol, size_t mtu) {
 
         h = DNS_PACKET_HEADER(p);
 
-        switch (protocol) {
-        case DNS_PROTOCOL_LLMNR:
-                /* no recursion for link-local resolving protocols */
-                rd = 0;
-                break;
-
-        default:
-                /* ask for recursion */
-                rd = 1;
-                break;
-        }
-
-        h->flags = htobe16(DNS_PACKET_MAKE_FLAGS(0  /* qr */,
-                                                 0  /* opcode */,
-                                                 0  /* aa */,
-                                                 0  /* tc */,
-                                                 rd /* rd */,
-                                                 0  /* ra */,
-                                                 0  /* ad */,
-                                                 0  /* cd */,
-                                                 0  /* rcode */));
+        if (protocol == DNS_PROTOCOL_LLMNR)
+                h->flags = htobe16(DNS_PACKET_MAKE_FLAGS(0 /* qr */,
+                                                         0 /* opcode */,
+                                                         0 /* c */,
+                                                         0 /* tc */,
+                                                         0 /* t */,
+                                                         0 /* ra */,
+                                                         0 /* ad */,
+                                                         0 /* cd */,
+                                                         0 /* rcode */));
+        else
+                h->flags = htobe16(DNS_PACKET_MAKE_FLAGS(0 /* qr */,
+                                                         0 /* opcode */,
+                                                         0 /* aa */,
+                                                         0 /* tc */,
+                                                         1 /* rd (ask for recursion) */,
+                                                         0 /* ra */,
+                                                         0 /* ad */,
+                                                         0 /* cd */,
+                                                         0 /* rcode */));
 
         *ret = p;
         return 0;