Hi,
The "Calculating line numbers" echo in less(1) is meant to
fire after an interval has elapsed, so we should use the
monotonic clock to measure.
Currently, if the system time is changed during the execution
of find_linenum() the echo fires too quickly or not at all.
--
Scott Cheloha
Index: usr.bin/less/linenum.c
===================================================================
RCS file: /cvs/src/usr.bin/less/linenum.c,v
retrieving revision 1.16
diff -u -p -r1.16 linenum.c
--- usr.bin/less/linenum.c 30 Dec 2016 19:52:43 -0000 1.16
+++ usr.bin/less/linenum.c 22 Nov 2017 22:11:52 -0000
@@ -33,6 +33,10 @@
* called to make sure we cache line numbers often enough.
*/
+#include <sys/time.h>
+
+#include <time.h>
+
#include "less.h"
/*
@@ -197,14 +201,30 @@ add_lnum(off_t linenum, off_t pos)
}
static int loopcount;
-static time_t startime;
+static struct timespec timeout;
+
+static void
+timeout_set(int seconds)
+{
+ clock_gettime(CLOCK_MONOTONIC, &timeout);
+ timeout.tv_sec += seconds;
+}
+
+static int
+timeout_elapsed(void)
+{
+ struct timespec now;
+
+ clock_gettime(CLOCK_MONOTONIC, &now);
+ return timespeccmp(&now, &timeout, >=);
+}
static void
longish(void)
{
if (loopcount >= 0 && ++loopcount > 100) {
loopcount = 0;
- if (time(NULL) >= startime + LONGTIME) {
+ if (timeout_elapsed()) {
ierror("Calculating line numbers", NULL);
loopcount = -1;
}
@@ -274,7 +294,7 @@ find_linenum(off_t pos)
* The decision is based on which way involves
* traversing fewer bytes in the file.
*/
- startime = time(NULL);
+ timeout_set(LONGTIME);
if (p == &anchor || pos - p->prev->pos < p->pos - pos) {
/*
* Go forward.
