fix: clock_gettime instead of clock

src/timer.c

@@ -1,3 +1,4 @@
+#include <bits/time.h>
 #include <limits.h>
 #include <time.h>
 
@@ -8,7 +9,7 @@
 void timer_init(Timer *timer, const unsigned int target) {
   timer->counter = 0;
   timer->target = target;
-  timer->start = clock();
+  clock_gettime(CLOCK_REALTIME, &timer->start);
 }
 
 bool timer_inc(Timer *timer) {
@@ -17,13 +18,16 @@ bool timer_inc(Timer *timer) {
 }
 
 double timer_reset(Timer *timer) {
-  clock_t stop;
+  struct timespec stop;
   double secs;
   double per_secs;
 
-  stop = clock();
+  if (clock_gettime(CLOCK_REALTIME, &stop) != 0) {
+    return 0.0;
+  }
 
-  secs = (double)(stop - timer->start) / CLOCKS_PER_SEC;
+  secs = (double)(stop.tv_sec - timer->start.tv_sec) +
+         (double)(stop.tv_nsec - timer->start.tv_nsec) / 1e9;
   per_secs = (double)timer->counter / secs;
 
   timer->start = stop;