ntp: Use mnemonic when specifying the request precision

This patch uses a mnemonic to specify the request precision and also
adds a comment how a future implementation might pass along the actual
system wall clock precision.

diff --git a/src/ntp.c b/src/ntp.c
index 3e90741..e15bd08 100644 (file)
--- a/src/ntp.c
+++ b/src/ntp.c
@@ -120,10 +120,17 @@ static void send_packet(int fd, const char *server)
        struct sockaddr_in addr;
        ssize_t len;
 
+       /*
+        * At some point, we could specify the actual system precision with:
+        *
+        *   clock_getres(CLOCK_REALTIME, &ts);
+        *   msg.precision = (int)log2(ts.tv_sec + (ts.tv_nsec * 1.0e-9));
+        */
        memset(&msg, 0, sizeof(msg));
        msg.flags = NTP_FLAGS_ENCODE(NTP_FLAG_LI_NOTINSYNC, 4, NTP_FLAG_MD_CLIENT);
        msg.poll = 4;   // min
        msg.poll = 10;  // max
+       msg.precision = NTP_PRECISION_S;
 
        memset(&addr, 0, sizeof(addr));
        addr.sin_family = AF_INET;