Add timespec helper routines.

1 files changed, 4 insertions, 30 deletions

diff --git a/src/tsc.c b/src/tsc.c
index 28066a4..554a6d8 100644
--- a/src/tsc.c
+++ b/src/tsc.c
@@ -27,40 +27,14 @@
 double
 sandglass_tsc_resolution()
 {
-  static long tsc = 0, grains1, grains2;
-
-  int monotonic;
-  struct timespec ts;
+  static long tsc = 0;
+  static struct timespec ts = { .tv_sec = 0, .tv_nsec = 10000000L };
 
   if (tsc == 0) {
-    monotonic = sysconf(_SC_MONOTONIC_CLOCK) > 0;
-    if (monotonic) {
-      if (clock_gettime(CLOCK_MONOTONIC, &ts) != 0)
-        return 0.0/0.0;
-    } else {
-      if (clock_gettime(CLOCK_REALTIME, &ts) != 0)
-        return 0.0/0.0;
-    }
     tsc = sandglass_get_tsc();
-    grains1 = sandglass_timespec_grains(&ts);
-    grains2 = grains1;
-
-    while (((grains2 >= grains1) ? grains2 - grains1
-                                 : 1000000000L + (grains2 - grains1))
-           < 10000000L)
-    {
-      if (monotonic) {
-        if (clock_gettime(CLOCK_MONOTONIC, &ts) != 0)
-          return 0.0/0.0;
-      } else {
-        if (clock_gettime(CLOCK_REALTIME, &ts) != 0)
-          return 0.0/0.0;
-      }
-      grains2 = ts.tv_nsec;
-    }
-
+    sandglass_spin(&ts);
     tsc = sandglass_get_tsc() - tsc;
   }
 
-  return tsc*1.0e9/(grains2 - grains1);
+  return tsc*1.0e9/ts.tv_nsec;
 }