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grdc(6): de-obfuscate the timekeeping of now/delay

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- 'now' only contains current time readings
- delay is only used as parameter to nanosleep
- prev_sec contains the time_t of the previous loop iteration

Submitted by:	bde
MFC after:	2 weeks
This commit is contained in:
Ulrich Spörlein 2010-08-03 20:56:23 +00:00
parent 227405d48c
commit ec2368eb92
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=210827
1 changed files with 8 additions and 6 deletions
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14
games/grdc/grdc.c
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@ -55,6 +55,7 @@ int
main(int argc, char *argv[])
{
struct timespec delay;
time_t prev_sec;
long t, a;
int i, j, s, k;
int n;
@ -138,6 +139,7 @@ main(int argc, char *argv[])
attrset(COLOR_PAIR(2));
}
clock_gettime(CLOCK_REALTIME_FAST, &now);
prev_sec = now.tv_sec;
do {
mask = 0;
tm = localtime(&now.tv_sec);
@ -194,20 +196,20 @@ main(int argc, char *argv[])
}
movto(6, 0);
refresh();
clock_gettime(CLOCK_REALTIME_FAST, &delay);
if (delay.tv_sec == now.tv_sec) {
clock_gettime(CLOCK_REALTIME_FAST, &now);
if (now.tv_sec == prev_sec) {
if (delay.tv_nsec > 0) {
delay.tv_sec = 0;
delay.tv_nsec = 1000000000 - delay.tv_nsec;
delay.tv_nsec = 1000000000 - now.tv_nsec;
} else {
delay.tv_sec = 1;
delay.tv_nsec = 0;
}
nanosleep(&delay, NULL);
clock_gettime(CLOCK_REALTIME_FAST, &delay);
clock_gettime(CLOCK_REALTIME_FAST, &now);
}
n -= delay.tv_sec - now.tv_sec;
now.tv_sec = delay.tv_sec;
n -= now.tv_sec - prev_sec;
prev_sec = now.tv_sec;
if (sigtermed) {
standend();
clear();