sbm

commit 599b2293f0435b849393f5579610cd7da6cc1ae2
parent bc55bf1d7a442eb2454b172ee5212c31e018ba07
Author: sin <sin@2f30.org>
Date:   Tue, 23 Feb 2016 10:03:04 +0000

No need to impose a max sampling frequency

The minimum sampling period is 1 ms because the delay argument for
the program is an integer and specified in milliseconds.

Diffstat:
M
sbm.1
 | 
3
+--
M
sbm.c
 | 
22
+++++++++++-----------

2 files changed, 12 insertions(+), 13 deletions(-)
diff --git a/sbm.1 b/sbm.1
@@ -23,8 +23,7 @@ is 0, it will loop forever.  This is the default.
 .It Fl d Ar delay
 Sample interface statistics every
 .Ar delay
-ms.  The default delay is 1000 ms and the minimum delay
-is 100 ms.
+ms.  The default delay is 1000 ms.
 .It Fl i Ar interface
 Monitor the selected
 .Ar interface .
diff --git a/sbm.c b/sbm.c
@@ -40,8 +40,6 @@
 
 #include "arg.h"
 
-#define SAMPLINGPERIOD (100) /* sampling period in ms */
-
 char *argv0;
 
 void
@@ -214,6 +212,16 @@ tv2ms(struct timeval *tv)
 	return (tv->tv_sec * 1000) + ((tv->tv_usec + 500) / 1000);
 }
 
+int
+msleep(struct timeval *tv)
+{
+	struct timespec ts;
+
+	ts.tv_sec = tv->tv_sec;
+	ts.tv_nsec = tv->tv_usec * 1000;
+	return nanosleep(&ts, NULL);
+}
+
 void
 loop(char *ifname, long count, struct timeval *delay)
 {
@@ -227,16 +235,10 @@ loop(char *ifname, long count, struct timeval *delay)
 	getmonotime(&old);
 	sample(ifname, &oldrxbytes, &oldtxbytes, &oldrxpps, &oldtxpps);
 	for (;;) {
-		/*
-		 * This is the minimum sampling period that is supported and
-		 * is always less than or equal to the given delay.
-		 */
-		usleep(SAMPLINGPERIOD * 1000);
+		msleep(delay);
 		sample(ifname, &rxbytes, &txbytes, &rxpps, &txpps);
 		getmonotime(&now);
 		timersub(&now, &old, &diff);
-		if (timercmp(&diff, delay, <))
-			continue;
 		getmonotime(&old);
 		diffrxbits = (rxbytes - oldrxbytes) * 8;
 		difftxbits = (txbytes - oldtxbytes) * 8;
@@ -279,8 +281,6 @@ main(int argc, char *argv[])
 		delay = strtol(EARGF(usage()), &end, 10);
 		if (*end != '\0' || errno)
 			errx(1, "invalid delay");
-		if (delay < SAMPLINGPERIOD)
-			errx(1, "minimum delay is %d ms", SAMPLINGPERIOD);
 		break;
 	case 'i':
 		strncpy(ifname, EARGF(usage()), sizeof(ifname));