andyw.patch

A NTP client is a program which user can synchronize the time with time server assigned. This prog

Supplied by Andy Warner.  He needed a version for a shell-less
embedded system that
  1. combined -s and -l behavior
  2. provided initial frequency set
  3. didn't spew much on stdout or stderr
  4. sent important information to syslog
  5. had as small a binary as possible
This patch is the result.

diff -ur ntpclient_2003/ntpclient.c ntpclient-andy/ntpclient.c
--- ntpclient_2003/ntpclient.c	Sat Jul  5 12:30:17 2003
+++ ntpclient-andy/ntpclient.c	Wed Jun 25 07:41:44 2003
@@ -2,7 +2,7 @@
  * ntpclient.c - NTP client
  *
  * Copyright 1997, 1999, 2000, 2003  Larry Doolittle  <[e-mail]>
- * Last hack: July 5, 2003
+ * Last hack: May 16, 2003
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License (Version 2,
@@ -34,33 +34,52 @@
  *  labelled "XXXX fixme - non-automatic build configuration".
  */
 
+/*
+ * $Id: ntpclient.c,v 1.4 2003/06/25 14:41:44 andyw Exp $
+ */
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <netinet/in.h>
-#include <netdb.h>     /* gethostbyname */
+#include <netdb.h>
 #include <arpa/inet.h>
+#include <sys/utsname.h>
 #include <time.h>
+#include <sys/time.h>
 #include <unistd.h>
 #include <errno.h>
 #ifdef _PRECISION_SIOCGSTAMP
 #include <sys/ioctl.h>
 #endif
 
-#define ENABLE_DEBUG
+#ifdef	ENABLE_SYSLOG
+#include <syslog.h>
+#define	SYSLOG_IDENT	"ntpclient"
+#define	SYSLOG_OPTIONS	(LOG_NOWAIT | LOG_PID)
+#define	SYSLOG_FACILITY	LOG_CRON
+#define	LOG_OPTION	"L"
+int	logging = 0 ;
+#else
+#define	LOG_OPTION
+#define	logging	0
+#endif
+
+#ifdef	ENABLE_REPLAY
+#define	REPLAY_OPTION	"r"
+#else
+#define	REPLAY_OPTION
+#endif
 
 extern char *optarg;
 
 /* XXXX fixme - non-automatic build configuration */
 #ifdef linux
-#include <sys/utsname.h>
-#include <sys/time.h>
 typedef u_int32_t __u32;
 #include <sys/timex.h>
 #else
-extern struct hostent *gethostbyname(const char *name);
 extern int h_errno;
 #define herror(hostname) \
 	fprintf(stderr,"Error %d looking up hostname %s\n", h_errno,hostname)
@@ -120,6 +139,7 @@
 #define debug 0
 #define DEBUG_OPTION
 #endif
+int verbose = 0 ;	/* verbose flag, produce useful output on stdout */
 
 int get_current_freq(void)
 {
@@ -170,7 +190,7 @@
 		fprintf(stderr,"size error\n");
 		return;
 	}
-	bzero((char *) data,sizeof(data));
+	bzero(data,sizeof(data));
 	data[0] = htonl (
 		( LI << 30 ) | ( VN << 27 ) | ( MODE << 24 ) |
 		( STRATUM << 16) | ( POLL << 8 ) | ( PREC & 0xff ) );
@@ -276,6 +296,17 @@
 		if (debug) {
 			printf("set time to %lu.%.6lu\n", tv_set.tv_sec, tv_set.tv_usec);
 		}
+#ifdef	ENABLE_SYSLOG
+		if (logging) {
+			syslog(LOG_NOTICE, "Time set from remote server") ;
+		}
+#endif
+		/*
+		 * Only set the clock once, if we are subsequently locking.
+		 */
+		if (live) {
+			set_clock = 0 ;
+		}
 	}
 
 	if (debug) {
@@ -316,11 +347,19 @@
 			el_time+sec2u(disp), freq);
 		if (!debug && new_freq != freq) set_freq(new_freq);
 	}
-	printf("%d %.5d.%.3d  %8.1f %8.1f  %8.1f %8.1f %9d\n",
-		arrival->coarse/86400, arrival->coarse%86400,
-		arrival->fine/4294967, el_time, st_time,
-		(skew1-skew2)/2, sec2u(disp), freq);
-	fflush(stdout);
+	if (verbose) {
+		printf("%d %.5d.%.3d  %8.1f %8.1f  %8.1f %8.1f %9d\n",
+			arrival->coarse/86400, arrival->coarse%86400,
+			arrival->fine/4294967, el_time, st_time,
+			(skew1-skew2)/2, sec2u(disp), freq);
+		fflush(stdout);
+	}
+#ifdef	ENABLE_SYSLOG
+	if (logging) {
+		syslog(LOG_NOTICE, "Skew %.1fmS, freq adjust %d",
+					(skew1-skew2)/2000, freq) ;
+	}
+#endif
 	return(el_time-st_time);
 }
 
@@ -415,6 +454,7 @@
 	}
 }
 
+#ifdef ENABLE_REPLAY
 void do_replay(void)
 {
 	char line[100];
@@ -447,12 +487,23 @@
 		}
 	}
 }
+#endif
 
 void usage(char *argv0)
 {
 	fprintf(stderr,
 	"Usage: %s [-c count] [-d] -h hostname [-i interval] [-l]\n"
-	"\t[-p port] [-r] [-s] \n",
+	"\t[-p port] [-s] [-v] [-a <initial freq>]"
+#ifdef	ENABLE_SYSLOG
+	" [-L]"
+#endif
+#ifdef	ENABLE_DEBUG
+	" [-d]"
+#endif
+#ifdef	ENABLE_REPLAY
+	" [-r]"
+#endif
+	"\n",
 	argv0);
 }
 
@@ -467,12 +518,21 @@
 	/* int debug=0; is a global above */
 	int goodness=0;
 	char *hostname=NULL;          /* must be set */
+#ifdef	ENABLE_REPLAY
 	int replay=0;                 /* replay mode overrides everything */
+#endif
+	int initial_freq = 0 ;		/* Initial freq value to use */
 
+#ifdef	ENABLE_SYSLOG
+	openlog(SYSLOG_IDENT, SYSLOG_OPTIONS, SYSLOG_FACILITY) ;
+#endif
 	for (;;) {
-		c = getopt( argc, argv, "c:" DEBUG_OPTION "g:h:i:lp:rs");
+		c = getopt( argc, argv, "a:c:" DEBUG_OPTION LOG_OPTION REPLAY_OPTION "g:h:i:lp:sv");
 		if (c == EOF) break;
 		switch (c) {
+			case 'a':
+				initial_freq = atoi(optarg) ;
+				break ;
 			case 'c':
 				probe_count = atoi(optarg);
 				break;
@@ -481,6 +541,16 @@
 				++debug;
 				break;
 #endif
+#ifdef	ENABLE_SYSLOG
+			case 'L':
+				logging++ ;
+				break ;
+#endif
+#ifdef ENABLE_REPLAY
+			case 'r':
+				replay++;
+				break;
+#endif
 			case 'g':
 				goodness = atoi(optarg);
 				break;
@@ -496,26 +566,33 @@
 			case 'p':
 				udp_local_port = atoi(optarg);
 				break;
-			case 'r':
-				replay++;
-				break;
 			case 's':
 				set_clock++;
-				probe_count = 1;
 				break;
+			case 'v':
+				verbose++ ;
+				break ;
 			default:
 				usage(argv[0]);
 				exit(1);
 		}
 	}
+#ifdef ENABLE_REPLAY
 	if (replay) {
 		do_replay();
 		exit(0);
 	}
+#endif
 	if (hostname == NULL) {
 		usage(argv[0]);
 		exit(1);
 	}
+
+
+	if (set_clock && !live) {
+		probe_count = 1;
+	}
+
 	if (debug) {
 		printf("Configuration:\n"
 		"  -c probe_count %d\n"
@@ -525,9 +602,10 @@
 		"  -i interval    %d\n"
 		"  -l live        %d\n"
 		"  -p local_port  %d\n"
-		"  -s set_clock   %d\n",
+		"  -s set_clock   %d\n"
+		"  -v (verbose)   %d\n",
 		probe_count, debug, goodness, hostname, cycle_time,
-		live, udp_local_port, set_clock );
+		live, udp_local_port, set_clock, verbose );
 	}
 
 	/* Startup sequence */
@@ -538,6 +616,20 @@
 
 	setup_transmit(usd, hostname, NTP_PORT);
 
+	if (initial_freq) {
+		set_freq(initial_freq) ;
+#ifdef	ENABLE_SYSLOG
+		if (logging) {
+			syslog(LOG_NOTICE, "Initial freq adjust %d", initial_freq) ;
+		}
+#endif
+	}
+
+#ifdef	ENABLE_SYSLOG
+	if (logging) {
+		syslog(LOG_NOTICE, "Using server: %s", hostname) ;
+	}
+#endif
 	primary_loop(usd, probe_count, cycle_time, goodness);
 
 	close(usd);
diff -ur ntpclient_2003/phaselock.c ntpclient-andy/phaselock.c
--- ntpclient_2003/phaselock.c	Wed Jun  4 17:58:17 2003
+++ ntpclient-andy/phaselock.c	Wed Jun 25 07:41:44 2003
@@ -23,13 +23,15 @@
  *      - Write documentation  :-(
  */
 
-#include <stdio.h>
+/*
+ * $Id: phaselock.c,v 1.3 2003/06/25 14:41:44 andyw Exp $
+ */
 
-#define ENABLE_DEBUG
+#include <stdio.h>
 
 #define RING_SIZE 16
-#define MAX_CORRECT 250   /* ppm change to system clock */
-#define MAX_C ((MAX_CORRECT)*65536)
+#define	MAX_CORRECT	(400)		/* ppm to change system clock */
+#define	MAX_C		(MAX_CORRECT * 65536) 
 struct datum {
 	unsigned int absolute;
 	double skew;
@@ -61,6 +63,12 @@
 #define debug 0
 #define DEBUG_OPTION
 #endif
+extern int verbose ;
+
+#ifdef ENABLE_SYSLOG
+extern int logging ;
+#include <syslog.h>
+#endif
 
 /* draw a line from a to c, what the offset is of that line
  * where that line matches b's slope coordinate.
@@ -234,7 +242,7 @@
 		 * line segments in s.max vs. absolute space, which are
 		 * points in freq vs. dt space.  Find points in order of increasing
 		 * slope == freq */
-		dinit=1; last_slope=-2*MAX_CORRECT;
+		dinit=1; last_slope=-2 * MAX_CORRECT;
 		for (c=1, j=next_up(rp); ; j=nextj) {
 			nextj = search(rp, j, 1, 1, 0, &maxseg[c]);
 			        search(rp, j, 0, 1, 1, &check);
@@ -254,7 +262,7 @@
 		 * line segments in s.min vs. absolute space, which are
 		 * points in freq vs. dt space.  These points are found in
 		 * order of decreasing slope. */
-		dinit=1; last_slope=+2*MAX_CORRECT;
+		dinit=1; last_slope=+2 * MAX_CORRECT ;
 		for (c=1, j=next_up(rp); ; j=nextj) {
 			nextj = search(rp, j, 0, 0, 1, &minseg[c]);
 			        search(rp, j, 1, 0, 0, &check);
@@ -316,7 +324,10 @@
 		/*
 		 * Pass 5: decide on a new freq */
 		if (inconsistent) {
-			printf("# inconsistent\n");
+			if (verbose) printf("# inconsistent\n");
+#ifdef	ENABLE_SYSLOG
+			if (logging) syslog(LOG_WARNING, "Inconsistent sample") ;
+#endif
 		} else {
 			delta_f = find_df(&both_sides_now);
 			if (debug) printf("find_df() = %e\n", delta_f);
@@ -324,9 +335,11 @@
 			delta_freq = delta_f*65536+.5;
 			if (debug) printf("delta_f %f  delta_freq %d  bsn %d\n", delta_f, delta_freq, both_sides_now);
 			computed_freq -= delta_freq;
-			printf ("# box [( %.3f , %.1f ) ",  save_min.slope, save_min.offset);
-			printf (      " ( %.3f , %.1f )] ", save_max.slope, save_max.offset);
-			printf (" delta_f %.3f  computed_freq %d\n", delta_f, computed_freq);
+			if (verbose) {
+				printf ("# box [( %.3f , %.1f ) ",  save_min.slope, save_min.offset);
+				printf (      " ( %.3f , %.1f )] ", save_max.slope, save_max.offset);
+				printf (" delta_f %.3f  computed_freq %d\n", delta_f, computed_freq);
+			}
 
 			if (computed_freq < -MAX_C) computed_freq=-MAX_C;
 			if (computed_freq >  MAX_C) computed_freq= MAX_C;