Remove USE_PACKET_TIMESTAMP

It stopped working when ntp_packetstamp.c was split out
of ntp_io.c.  USE_PACKET_TIMESTAMP was defined in ntp_packetstamp.c
but referenced in ntp_io.c.

All modern systems support some form of capturing recv
time stamps via recvmsg.  The current code is using a time
stamp from shortly after the select returns.  We can restore
that action if necessary.  It seems to work OK on lightly
loaded systems.  (Very old code used SIGIO to capture
time stamps.)

devel/ifdex-ignores

@@ -144,7 +144,6 @@ UNUSED_LOCAL		# Used to quiet compiler warnings
 UPDATE_GRACE		# ntp_io.c only
 USE_COMPILETIME_PIVOT	# Use build date in disambiguating time.
 
-USE_PACKET_TIMESTAMP    # setup and used in ntp_io
 USE_SCM_BINTIME		# to grab timestamp for recv packet
 USE_SCM_TIMESTAMP	# "
 USE_SCM_TIMESTAMPNS	# "

ntpd/ntp_io.c

@@ -2040,9 +2040,7 @@ open_socket(
 		return INVALID_SOCKET;
 	}
 
-#ifdef USE_PACKET_TIMESTAMP
-	enable_packetstamps(fd);
-#endif /* USE_PACKET_TIMESTAMP */
+	enable_packetstamps(fd, addr);
 	
 	DPRINT(4, ("bind(%d) AF_INET%s, addr %s%%%u#%d, flags 0x%x\n",
 		   fd, IS_IPV6(addr) ? "6" : "", socktoa(addr),
@@ -2192,11 +2190,9 @@ read_network_packet(
 	socklen_t fromlen;
 	ssize_t buflen;
 	register struct recvbuf *rb;
-#ifdef USE_PACKET_TIMESTAMP
 	struct msghdr msghdr;
 	struct iovec iovec;
-	char control[CMSG_BUFSIZE];
-#endif
+	char control[100];   /* FIXME: Need space for time stamp plus overhead */
 
 	/*
 	 * Get a buffer and read the frame.  If we
@@ -2230,11 +2226,6 @@ read_network_packet(
 
 	fromlen = sizeof(rb->recv_srcadr);
 
-#ifndef USE_PACKET_TIMESTAMP
-	rb->recv_length = (size_t)recvfrom(fd, (char *)&rb->recv_space,
-				           sizeof(rb->recv_space), 0,
-				           &rb->recv_srcadr.sa, &fromlen);
-#else
 	iovec.iov_base        = &rb->recv_space;
 	iovec.iov_len         = sizeof(rb->recv_space);
 	msghdr.msg_name       = &rb->recv_srcadr;
@@ -2245,7 +2236,6 @@ read_network_packet(
 	msghdr.msg_control    = (void *)&control;
 	msghdr.msg_controllen = sizeof(control);
 	rb->recv_length       = recvmsg(fd, &msghdr, 0);
-#endif
 
 	buflen = (ssize_t)rb->recv_length;
 
@@ -2305,10 +2295,7 @@ read_network_packet(
 	rb->dstadr = itf;
 	rb->cast_flags = (uint8_t)(rb->fd == rb->dstadr->bfd ? MDF_BCAST : MDF_UCAST);
 	rb->fd = fd;
-#ifdef USE_PACKET_TIMESTAMP
-	/* pick up a network time stamp if possible */
 	ts = fetch_packetstamp(rb, &msghdr, ts);
-#endif
 	rb->recv_time = ts;
 	rb->receiver = receive;
 #ifdef REFCLOCK

ntpd/ntp_packetstamp.c

@@ -18,7 +18,6 @@
 #include "timespecops.h"
 
 #if defined(SO_BINTIME) && defined(SCM_BINTIME) && defined(CMSG_FIRSTHDR)
-#  define USE_PACKET_TIMESTAMP
 #  define USE_SCM_BINTIME
 /* UNUSED
  * #  ifdef OVERRIDE_BINTIME_CTLMSGBUF_SIZE
@@ -28,7 +27,6 @@
  * #  endif
  */
 #elif defined(SO_TIMESTAMPNS) && defined(SCM_TIMESTAMPNS) && defined(CMSG_FIRSTHDR)
-#  define USE_PACKET_TIMESTAMP
 #  define USE_SCM_TIMESTAMPNS
 /* UNUSED
  * #  ifdef OVERRIDE_TIMESTAMPNS_CTLMSGBUF_SIZE
@@ -38,7 +36,6 @@
  * #  endif
  */
 #elif defined(SO_TIMESTAMP) && defined(SCM_TIMESTAMP) && defined(CMSG_FIRSTHDR)
-#  define USE_PACKET_TIMESTAMP
 #  define USE_SCM_TIMESTAMP
 /* UNUSED
  * #  ifdef OVERRIDE_TIMESTAMP_CTLMSGBUF_SIZE
@@ -48,6 +45,7 @@
  * #  endif
  */
 #else
+# error "Can't get packet timestamp"
 /* fill in for old/other timestamp interfaces */
 #endif
 
@@ -102,7 +100,6 @@ enable_packetstamps(
 }
 
 
-#ifdef USE_PACKET_TIMESTAMP
 /*
  * extract timestamps from control message buffer
  */
@@ -226,6 +223,5 @@ fetch_packetstamp(
 	}
 	return ts;
 }
-#endif	/* USE_PACKET_TIMESTAMP */
 
 // end