From 85bbc6321547124ec3bd8f8dc4af4c91e5905edc Mon Sep 17 00:00:00 2001
From: Owen Williams <owilliams@mixxx.org>
Date: Mon, 31 May 2021 22:58:19 -0400
Subject: [PATCH] Sync Lock: don't use c++17 inline conditional assignment (1)
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Co-authored-by: Daniel Schürmann <daschuer@mixxx.org>
---
 src/engine/sync/enginesync.cpp | 22 +++++++++++++---------
 src/engine/sync/enginesync.h   |  6 +++---
 2 files changed, 16 insertions(+), 12 deletions(-)

diff --git a/src/engine/sync/enginesync.cpp b/src/engine/sync/enginesync.cpp
index 1b8e876e010..4655286ccab 100644
--- a/src/engine/sync/enginesync.cpp
+++ b/src/engine/sync/enginesync.cpp
@@ -96,8 +96,9 @@ void EngineSync::requestSyncMode(Syncable* pSyncable, SyncMode mode) {
         }
     }
 
-    if (auto onlyPlayer = getOnlyPlayingSyncable(); onlyPlayer != nullptr) {
-        onlyPlayer->notifyOnlyPlayingSyncable();
+    Syncable* pOnlyPlayer = getUniqueSyncDeck();
+    if (pOnlyPlayer) {
+        pOnlyPlayer->notifyOnlyPlayingSyncable();
     }
 }
 
@@ -351,11 +352,14 @@ void EngineSync::notifyPlayingAudible(Syncable* pSyncable, bool playingAudible)
     if (newMaster != nullptr && newMaster != m_pMasterSyncable) {
         activateMaster(newMaster, SYNC_MASTER_SOFT);
         setMasterParams(newMaster);
-    } else if (auto onlyPlayer = getOnlyPlayingSyncable(); onlyPlayer != nullptr) {
-        // Even if we didn't change master, if there is only one player (us), then we should
-        // reinit the beat distance.
-        onlyPlayer->notifyOnlyPlayingSyncable();
-        setMasterBeatDistance(onlyPlayer, onlyPlayer->getBeatDistance());
+    } else {
+        Syncable* pOnlyPlayer = getUniqueSyncDeck();
+        if (pOnlyPlayer) {
+            // Even if we didn't change master, if there is only one player (us), then we should
+            // reinit the beat distance.
+            pOnlyPlayer->notifyOnlyPlayingSyncable();
+            setMasterBeatDistance(pOnlyPlayer, pOnlyPlayer->getBeatDistance());
+        }
     }
 
     pSyncable->requestSync();
@@ -613,7 +617,7 @@ void EngineSync::setMasterParams(Syncable* pSource) {
     if (!pSource->isPlaying()) {
         // If the params source is not playing, but other syncables are, then we are a stopped
         // explicit Master and we should not initialize the beat distance.  Take it from the
-        // internal clock instead.
+        // internal clock instead, because that will be up to date with the playing deck(s).
         bool playingSyncables = false;
         for (Syncable* pSyncable : qAsConst(m_syncables)) {
             if (pSyncable == pSource) {
@@ -651,7 +655,7 @@ void EngineSync::setMasterParams(Syncable* pSource) {
     }
 }
 
-Syncable* EngineSync::getOnlyPlayingSyncable() const {
+Syncable* EngineSync::getUniqueSyncDeck() const {
     Syncable* onlyPlaying = nullptr;
     for (Syncable* pSyncable : m_syncables) {
         if (!pSyncable->isSynchronized()) {
diff --git a/src/engine/sync/enginesync.h b/src/engine/sync/enginesync.h
index 4988a14c422..016733aadcf 100644
--- a/src/engine/sync/enginesync.h
+++ b/src/engine/sync/enginesync.h
@@ -115,9 +115,9 @@ class EngineSync : public SyncableListener {
 
     void setMasterParams(Syncable* pSource);
 
-    /// Iff there is a single playing syncable, return it. This is used to initialize master
-    /// params.
-    Syncable* getOnlyPlayingSyncable() const;
+    /// Iff there is a single playing syncable in sync mode, return it.
+    /// This is used to initialize master params.
+    Syncable* getUniqueSyncDeck() const;
 
     /// Only for testing. Do not use.
     Syncable* getSyncableForGroup(const QString& group);