1 files changed, 17 insertions, 17 deletions

diff --git a/status.c b/status.c
index c2b8bd0..2349547 100644
--- a/status.c
+++ b/status.c
@@ -380,7 +380,7 @@ time_add(struct timespec a, struct timespec b) {
   dst.tv_nsec = a.tv_nsec + b.tv_nsec;
 
   /* larger than 1 second in μsec */
-  if (dst.tv_nsec >= 1000000) {
+  if (dst.tv_nsec >= 1000000 * 1000) {
     dst.tv_nsec -= 1000000 * 1000;
     dst.tv_sec++;
   }
@@ -393,8 +393,8 @@ static struct timespec
 time_sub(struct timespec a, struct timespec b) {
   struct timespec dst;
 
-  dst.tv_sec  = a.tv_sec + b.tv_sec;
-  dst.tv_nsec = a.tv_nsec + b.tv_nsec;
+  dst.tv_sec  = a.tv_sec - b.tv_sec;
+  dst.tv_nsec = a.tv_nsec - b.tv_nsec;
 
   if (dst.tv_nsec < 0) {
     dst.tv_nsec += 1000000 * 1000;
@@ -426,39 +426,38 @@ main(void) {
     unsigned i;
 
     /* Stall updating for at most 1 minute */
-    struct timespec next_update = {0};
-    now                         = time_add(one_minute, next_update);
+    struct timespec next_update = time_add(now, one_minute);
 
     for (i = 0; i < num_elems; i++) {
-      struct timespec next_fire = {0};
-      struct element* e         = &statusbar[i];
-
-      e->fire_previous          = time_add(e->fire_interval, next_fire);
+      struct element* e = &statusbar[i];
+      // Next time this element updates
+      struct timespec next_fire = time_add(e->fire_previous, e->fire_interval);
 
+      /* test if this is not to be updated yet */
       if (time_lt(now, next_fire)) {
-        /* Check if this is the next to-be-updated element */
+        /* test if this element is to be updated next */
         if (time_lt(next_fire, next_update)) {
           next_update = next_fire;
         }
         continue;
       }
 
+      /* Otherwise update this element */
       memset(e->buf, 0, ELEMENT_STRBUF_SZ);
 
       e->f(statusbar[i].buf);
       e->fire_previous = now;
 
       /* Check if this element needs to be refreshed next, again */
-      e->fire_previous = time_add(e->fire_interval, next_fire);
-
+      next_fire = time_add(now, e->fire_interval);
       if (time_lt(next_fire, next_update)) {
         next_update = next_fire;
       }
 
       /* printf("[%ld.%ld]  %s\n",
-       * statusbar[i].fire_interval.tv_sec,
-       * statusbar[i].fire_interval.tv_usec,
-       * (char*)statusbar[i].buf);
+       * e->fire_interval.tv_sec,
+       * e->fire_interval.tv_nsec,
+       * (char*)e->buf);
        */
     }
 
@@ -480,11 +479,12 @@ main(void) {
     puts(buf);
     fflush(stdout);
 
-    next_update = time_sub(now, next_update);
+    struct timespec sleep_for = time_sub(next_update, now);
+    sleep_for                 = time_add(sleep_for, (struct timespec){0, 500});
 
     /* Replace NULL to get "remaining time", in case we got
      * interrupted / signaled */
-    nanosleep(&next_update, NULL);
+    nanosleep(&sleep_for, NULL);
   }
 
   return 0;