Fix sleep delay to include encoding time

Up to now the delay between two loop runs was slightly higher than the specified
sleep delay as the sleeping process did not consider the time the PAD encoding
needs but rather sleeped for the set sleep delay.

This is now fixed by using a steady clock.

1 files changed, 6 insertions, 1 deletions

diff --git a/src/odr-padenc.cpp b/src/odr-padenc.cpp
index d82d4c8..0d19fd6 100644
--- a/src/odr-padenc.cpp
+++ b/src/odr-padenc.cpp
@@ -32,6 +32,7 @@
 #include <stdlib.h>
 #include <string>
 #include <list>
+#include <thread>
 #include <vector>
 #include <sys/types.h>
 #include <fcntl.h>
@@ -304,6 +305,8 @@ int main(int argc, char *argv[]) {
     std::list<slide_metadata_t> slides_to_transmit;
     History slides_history(History::MAXHISTORYLEN);
 
+    std::chrono::steady_clock::time_point next_run = std::chrono::steady_clock::now();
+
     while(1) {
         // try to read slides dir (if present)
         if (sls_dir && slides_to_transmit.empty()) {
@@ -349,7 +352,9 @@ int main(int argc, char *argv[]) {
         // flush all remaining PADs
         pad_packetizer.WriteAllPADs(output_fd);
 
-        sleep(sleepdelay);
+        // sleep until next run
+        next_run += std::chrono::seconds(sleepdelay);
+        std::this_thread::sleep_until(next_run);
     }
 
     return 1;