Add ability to output clock drift and corrections applied, both in microseconds.

common.h

@@ -120,6 +120,8 @@ uint32_t uatoi(const char *nptr);
 shairport_cfg config;
 config_t config_file_stuff;
 
+int64_t session_corrections;
+
 void command_start(void);
 void command_stop(void);
 

player.c

@@ -855,6 +855,7 @@ typedef struct stats { // statistics for running averages
 } stats_t;
 
 static void *player_thread_func(void *arg) {
+		session_corrections = 0;
 	// check that there are enough buffers to accommodate the desired latency and the latency offset
 	
 	int maximum_latency = config.latency+config.audio_backend_latency_offset;
@@ -1115,11 +1116,14 @@ static void *player_thread_func(void *arg) {
 
           tsum_of_sync_errors += sync_error;
           tsum_of_drifts += statistics[newest_statistic].drift;
-          if (amount_to_stuff > 0)
+          if (amount_to_stuff > 0) {
             tsum_of_insertions_and_deletions += amount_to_stuff;
-          else
+          } else {
             tsum_of_insertions_and_deletions -= amount_to_stuff;
+          }
           tsum_of_corrections += amount_to_stuff;
+          session_corrections += amount_to_stuff;
+
 
           newest_statistic = (newest_statistic + 1) % trend_interval;
           number_of_statistics++;

rtp.c

@@ -406,15 +406,21 @@ static void *rtp_timing_receiver(void *arg) {
       }
       
      uint64_t clock_drift;
+     int64_t current_delay;
+//     if (config.output->delay) {
+//            current_delay = config.output->delay();
+//      }
       if (first_local_to_remote_time_difference>=local_to_remote_time_difference)  {
         clock_drift = ((first_local_to_remote_time_difference - local_to_remote_time_difference) * 1000000)>>32;
-        debug(1, "-%llu", clock_drift);
+//        debug(1, "-%llu\t%lld\t%lld", clock_drift,(session_corrections*1000000)/44100,current_delay);
+        debug(1, "-%llu\t%lld", clock_drift,(session_corrections*1000000)/44100);
         //debug(1,"Clock drift is -%lld usec.",clock_drift);
       }
       else {
         clock_drift = ((local_to_remote_time_difference - first_local_to_remote_time_difference) * 1000000) >>32;
         //debug(1,"Clock drift is %lld usec.",clock_drift);
-        debug(1, "%llu", clock_drift);
+//        debug(1, "%llu\t%lld\t%lld", clock_drift,(session_corrections*1000000)/44100,current_delay);
+        debug(1, "%llu\t%lld\t", clock_drift,(session_corrections*1000000)/44100);
       }
       
     } else {