cwTime.h/cpp, cwMutex.cpp : Time now depends on CLOCK_MONOTONIC instead of CLOCK_REALTIME.

mutex::lock() apparently depends on CLOCK_REALTIME and so that is now handled with a direct call to clock_gettime().

cwMutex.cpp

@@ -104,7 +104,11 @@ cw::rc_t cw::mutex::lock( handle_t h, unsigned timeout_milliseconds )
   int      sysRc;
   time::spec_t ts;
 
-  time::get(ts);
+  // Apparently timedlock depends on using CLOCK_REALTIME vs CLOCK_MONOTONIC
+  // so we can't call to time::current_time() which uses CLOCK_MONOTONIC.
+  // TODO: See this: https://stackoverflow.com/questions/14248033/clock-monotonic-and-pthread-mutex-timedlock-pthread-cond-timedwait
+  // and consider changing this to use CLOCK_MONOTONIC.
+  clock_gettime(CLOCK_REALTIME,&ts); 
   time::advanceMs(ts,timeout_milliseconds);
   
   

cwTime.cpp

@@ -44,11 +44,16 @@ void cw::time::get( spec_t& t )
 #include <sys/time.h> // gettimeofday()
 void cw::time::get( spec_t& t )
 {
-  // NOTcw::mutex::lock(h,timeout) relies on using 
-  // CLOCK_REALTIME.  If the source of this clock changes
-  // then change cw::mutex::loc(h,timeout) as well  
-  clock_gettime(CLOCK_REALTIME,&t);
+  clock_gettime(CLOCK_MONOTONIC,&t);
 }
+
+cw::time::spec_t cw::time::current_time()
+{
+  spec_t t;
+  clock_gettime(CLOCK_REALTIME,&t);
+  return t;
+}
+
 #endif
 
 // this assumes that the seconds have been normalized to a recent start time
@@ -177,8 +182,8 @@ cw::rc_t cw::time::now( spec_t& ts )
   
   memset(&ts,0,sizeof(ts));
   
-  if((errRC = clock_gettime(CLOCK_REALTIME, &ts)) != 0 )
-  		rc = cwLogSysError(kInvalidOpRC,errRC,"Unable to obtain system time.");
+  if((errRC = clock_gettime(CLOCK_MONOTONIC, &ts)) != 0 )
+    rc = cwLogSysError(kInvalidOpRC,errRC,"Unable to obtain system time.");
 
   return rc;
 }

cwTime.h

@@ -20,6 +20,7 @@ namespace cw
 
     // Get the time 
     void get( spec_t& tRef );
+    spec_t current_time(); // same as get()
 
     // Return the elapsed time (t1 - t0) in microseconds
     // t1 is assumed to be at a later time than t0.
@@ -61,7 +62,7 @@ namespace cw
 
     void setZero( spec_t& t0 );
 
-    rc_t now( spec_t& ts );
+    rc_t now( spec_t& ts ); // same as get()
 
     void subtractMicros( spec_t& ts, unsigned us );