From: Mike Brady <mikebrady@eircom.net>
Date: Sun, 27 Mar 2016 14:59:02 +0000 (+0000)
Subject: Make time_to_play a uint64_t and correctly handle addition or subtraction of the... 
X-Git-Tag: 2.9.5.2~4
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ee240f2f6fe7c9d3446d04f2b411a2b6628d4aa2;p=thirdparty%2Fshairport-sync.git

Make time_to_play a uint64_t and correctly handle addition or subtraction of the delta -- possible bug fix. Check types of arguments associated with caulcuation whether to wait or not.
---

diff --git a/player.c b/player.c
index 5f9127b5..af4e789f 100644
--- a/player.c
+++ b/player.c
@@ -451,7 +451,7 @@ static abuf_t *buffer_get_frame(void) {
   int32_t dac_delay = 0;
   do {
     // get the time
-    local_time_now = get_absolute_time_in_fp();
+    local_time_now = get_absolute_time_in_fp(); // type okay
 
     // if config.timeout (default 120) seconds have elapsed since the last audio packet was
     // received, then we should stop.
@@ -686,21 +686,21 @@ static abuf_t *buffer_get_frame(void) {
     	do_wait = 1; // if the current frame exists and is ready, then wait unless it's time to let it go...
       uint32_t reference_timestamp;
       uint64_t reference_timestamp_time,remote_reference_timestamp_time;
-      get_reference_timestamp_stuff(&reference_timestamp, &reference_timestamp_time, &remote_reference_timestamp_time);
+      get_reference_timestamp_stuff(&reference_timestamp, &reference_timestamp_time, &remote_reference_timestamp_time); // all types okay
       if (reference_timestamp) { // if we have a reference time
-        uint32_t packet_timestamp = curframe->timestamp;
-        int64_t delta = ((int64_t)packet_timestamp - (int64_t)reference_timestamp);
-        int64_t offset = (int64_t)config.latency + config.audio_backend_latency_offset -
-                         (int64_t)config.audio_backend_buffer_desired_length;
-        int64_t net_offset = delta + offset;
-        int64_t time_to_play = reference_timestamp_time;
-        int64_t net_offset_fp_sec;
+        uint32_t packet_timestamp = curframe->timestamp; // types okay
+        int64_t delta = (int64_t)packet_timestamp - (int64_t)reference_timestamp; // uint32_t to int64_t is okay.
+        int64_t offset = config.latency + config.audio_backend_latency_offset -
+                         config.audio_backend_buffer_desired_length; // all arguments are int32_t, so expression promotion okay
+        int64_t net_offset = delta + offset; // okay
+        uint64_t time_to_play = reference_timestamp_time; // type okay
         if (net_offset >= 0) {
-          net_offset_fp_sec = (net_offset << 32) / 44100;
+          uint64_t net_offset_fp_sec = (net_offset << 32) / 44100; // int64_t which is positive
           time_to_play += net_offset_fp_sec; // using the latency requested...
           // debug(2,"Net Offset: %lld, adjusted: %lld.",net_offset,net_offset_fp_sec);
         } else {
-          net_offset_fp_sec = ((-net_offset) << 32) / 44100;
+          int64_t abs_net_offset = -net_offset;
+          uint64_t net_offset_fp_sec = (abs_net_offset << 32) / 44100; // int64_t which is positive
           time_to_play -= net_offset_fp_sec;
           // debug(2,"Net Offset: %lld, adjusted: -%lld.",net_offset,net_offset_fp_sec);
         }