Mac specific patch for clock_gettime

src/snark/src/common/profiling.cpp

@@ -26,6 +26,11 @@
 #include <proc/readproc.h>
 #endif
 
+#ifdef __APPLE__
+#include <sys/time.h>
+#include <sys/resource.h>
+#endif
+
 namespace libsnark {
 
 long long get_nsec_time()
@@ -38,10 +43,20 @@ long long get_nsec_time()
 long long get_nsec_cpu_time()
 {
     ::timespec ts;
+#ifdef __APPLE__
+     /* from latest Apple Libc: clock_gettime(CLOCK_PROCESS_CPUTIME_ID)
+     https://opensource.apple.com/source/Libc/Libc-1244.1.7/gen/clock_gettime.c.auto.html */
+     struct rusage ru;
+     if (getrusage(RUSAGE_SELF, &ru))
+         throw ::std::runtime_error("getrusage(RUSAGE_SELF) to get cpu time failed");
+     timeradd(&ru.ru_utime, &ru.ru_stime, &ru.ru_utime);
+     TIMEVAL_TO_TIMESPEC(&ru.ru_utime, &ts);
+#else    
     if ( ::clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &ts) )
         throw ::std::runtime_error("clock_gettime(CLOCK_PROCESS_CPUTIME_ID) failed");
         // If we expected this to work, don't silently ignore failures, because that would hide the problem and incur an unnecessarily system-call overhead. So if we ever observe this exception, we should probably add a suitable #ifdef .
         //TODO: clock_gettime(CLOCK_PROCESS_CPUTIME_ID) is not supported by native Windows. What about Cygwin? Should we #ifdef on CLOCK_PROCESS_CPUTIME_ID or on __linux__?
+#endif
     return ts.tv_sec * 1000000000ll + ts.tv_nsec;
 }