X-Git-Url: http://g0dil.de/git?a=blobdiff_plain;f=Scheduler%2FClockService.cci;h=f5369314462f01da5aba2555b3e2c5631f44c5e9;hb=bf6bdcb90de19ed474535d41c5519518921b717b;hp=9628ec600f4e16806570c105cb1e4249e29cb114;hpb=dd9cab12c8a33e57da1dd1104b530e8ea1591c53;p=senf.git

diff --git a/Scheduler/ClockService.cci b/Scheduler/ClockService.cci
index 9628ec6..f536931 100644
--- a/Scheduler/ClockService.cci
+++ b/Scheduler/ClockService.cci
@@ -1,8 +1,8 @@
 // $Id$
 //
-// Copyright (C) 2007 
-// Fraunhofer Institut fuer offene Kommunikationssysteme (FOKUS)
-// Kompetenzzentrum fuer Satelitenkommunikation (SatCom)
+// Copyright (C) 2007
+// Fraunhofer Institute for Open Communication Systems (FOKUS)
+// Competence Center NETwork research (NET), St. Augustin, GERMANY
 //     Stefan Bund <g0dil@berlios.de>
 //
 // This program is free software; you can redistribute it and/or modify
@@ -24,7 +24,7 @@
     \brief ClockService inline non-template implementation */
 
 // Custom includes
-#include "boost/date_time/posix_time/posix_time_types.hpp"
+#include <boost/date_time/posix_time/posix_time_types.hpp>
 
 #define prefix_ inline
 ///////////////////////////////cci.p///////////////////////////////////////
@@ -32,43 +32,159 @@
 ///////////////////////////////////////////////////////////////////////////
 // senf::ClockService
 
-prefix_ senf::ClockService::~ClockService()
+prefix_ senf::ClockService::clock_type senf::ClockService::now()
 {
-    
+    return instance().now_m();
 }
 
-prefix_ senf::ClockService::clock_type senf::ClockService::now()
+prefix_ senf::ClockService::abstime_type senf::ClockService::abstime(clock_type clock)
 {
-    return clock(boost::posix_time::microsec_clock::universal_time());
+    return instance().abstime_m(clock);
 }
 
-prefix_ senf::ClockService::abstime_type senf::ClockService::abstime(clock_type clock)
+prefix_ senf::ClockService::clock_type senf::ClockService::clock(abstime_type time)
+{
+    return instance().clock_m(time);
+}
+
+prefix_ senf::ClockService::clock_type senf::ClockService::from_time_t(time_t const & time)
+{
+    return clock( boost::posix_time::from_time_t(time) );
+}
+
+prefix_ senf::ClockService::clock_type senf::ClockService::from_timeval(timeval const & time)
+{
+    return from_time_t(time.tv_sec) + ClockService::microseconds(time.tv_usec);
+}
+
+prefix_ senf::ClockService::clock_type senf::ClockService::nanoseconds(int64_type v)
+{
+    return v;
+}
+
+prefix_ senf::ClockService::clock_type senf::ClockService::microseconds(int64_type v)
+{
+    return v * nanoseconds(1000);
+}
+
+prefix_ senf::ClockService::clock_type senf::ClockService::milliseconds(int64_type v)
+{
+    return v * microseconds(1000);
+}
+
+prefix_ senf::ClockService::clock_type senf::ClockService::seconds(int64_type v)
+{
+    return v * milliseconds(1000);
+}
+
+prefix_ senf::ClockService::clock_type senf::ClockService::minutes(int64_type v)
+{
+    return v * seconds(60);
+}
+
+prefix_ senf::ClockService::clock_type senf::ClockService::hours(int64_type v)
+{
+    return v * minutes(60);
+}
+
+prefix_ senf::ClockService::clock_type senf::ClockService::days(int64_type v)
+{
+    return v * hours(24);
+}
+
+prefix_ senf::ClockService::clock_type senf::ClockService::in_nanoseconds(int64_type v)
+{
+    return v;
+}
+
+prefix_ senf::ClockService::clock_type senf::ClockService::in_microseconds(int64_type v)
+{
+    return v / nanoseconds(1000);
+}
+
+prefix_ senf::ClockService::clock_type senf::ClockService::in_milliseconds(int64_type v)
+{
+    return v / microseconds(1000);
+}
+
+prefix_ senf::ClockService::clock_type senf::ClockService::in_seconds(int64_type v)
+{
+    return v / milliseconds(1000);
+}
+
+prefix_ senf::ClockService::clock_type senf::ClockService::in_minutes(int64_type v)
+{
+    return v / seconds(60);
+}
+
+prefix_ senf::ClockService::clock_type senf::ClockService::in_hours(int64_type v)
+{
+    return v / minutes(60);
+}
+
+prefix_ senf::ClockService::clock_type senf::ClockService::in_days(int64_type v)
+{
+    return v / hours(24);
+}
+
+prefix_ void senf::ClockService::restart()
+{
+    instance().restart_m();
+}
+
+////////////////////////////////////////
+// private members
+
+prefix_ senf::ClockService::clock_type senf::ClockService::now_m()
+{
+    // We want to make the normal case (no skew) really fast. This first 'checkSkew' *might*
+    // transiently fail if a SIGALRM is delivered in the midst of the test. updateSkew will
+    // therefore block signals and do the check again to make sure.
+    //
+    // The opposite case (the test returns 'false' even though it should return 'true') is so highly
+    // improbable that it is treated as academic. (it will be catched by the next SIGALRM)
+
+    boost::posix_time::ptime time (boost::posix_time::microsec_clock::universal_time());
+    if (checkSkew(time)) 
+        updateSkew(time);
+    
+    // 'clock' will pick up the corrected base_ value if needed.
+    return clock_m(time);
+}
+
+prefix_ senf::ClockService::abstime_type senf::ClockService::abstime_m(clock_type clock)
 {
 #ifdef BOOST_DATE_TIME_POSIX_TIME_STD_CONFIG
-    return instance().base_ + boost::posix_time::nanoseconds(clock);
+    return base_ + boost::posix_time::nanoseconds(clock);
 #else
-    return instance().base_ + boost::posix_time::microseconds((clock+500)/1000);
+    return base_ + boost::posix_time::microseconds((clock+500)/1000);
 #endif
 }
 
-prefix_ senf::ClockService::clock_type senf::ClockService::clock(abstime_type time)
+prefix_ senf::ClockService::clock_type senf::ClockService::clock_m(abstime_type time)
 {
-    boost::posix_time::time_duration delta (time - instance().base_);
+    ///\fixme What happens, if base_ is changed in SIGALRM while reading it here ?
+
+    // Idea: Have *two* base values: one is written by the SIGALRM handler, the other is only
+    // Written by synchronous code. If they differ, we block signals, copy over and continue.  If
+    // they transiently differ because we are reading the SIGALRM value while it is being changed
+    // this does not matter: We will then still copy it over.
+
+    boost::posix_time::time_duration delta (time - base_);
     return clock_type( delta.ticks() )
         * clock_type( 1000000000UL / boost::posix_time::time_duration::ticks_per_second() );
 }
 
-////////////////////////////////////////
-// private members
-
-prefix_ senf::ClockService::ClockService()
-    : base_ (boost::posix_time::microsec_clock::universal_time())
-{}
+prefix_ bool senf::ClockService::checkSkew(boost::posix_time::ptime time)
+{
+    boost::posix_time::ptime h (heartbeat_); // reduce chance for race condition
+    return time < h || (time - h) > boost::posix_time::seconds(2*CheckInterval);
+}
 
-prefix_ senf::ClockService & senf::ClockService::instance()
+prefix_ void senf::ClockService::clockSkew(boost::posix_time::ptime time,
+                                           boost::posix_time::ptime expected)
 {
-    static ClockService instance;
-    return instance;
+    base_ += (time - expected);
 }
 
 ///////////////////////////////cci.e///////////////////////////////////////