Applied fixes from code review

srtcore/api.cpp

@@ -1916,11 +1916,11 @@ int srt::CUDTUnited::close(const SRTSOCKET u)
 #if ENABLE_HEAVY_LOGGING
     // Wrapping the log into a destructor so that it
     // is printed AFTER the destructor of SocketKeeper.
-    struct ForceDestructor
+    struct ScopedExitLog
     {
-        CUDTSocket* ps;
-        ForceDestructor(): ps(NULL){}
-        ~ForceDestructor()
+        const CUDTSocket* const ps;
+        ScopedExitLog(const CUDTSocket* p): ps(p){}
+        ~ScopedExitLog()
         {
             if (ps) // Could be not acquired by SocketKeeper, occasionally
             {
@@ -1931,11 +1931,10 @@ int srt::CUDTUnited::close(const SRTSOCKET u)
 #endif
 
     SocketKeeper k(*this, u, ERH_THROW);
-    IF_HEAVY_LOGGING(fod.ps = k.socket);
+    IF_HEAVY_LOGGING(ScopedExitLog slog(k.socket));
     HLOGC(smlog.Debug, log << "CUDTUnited::close/begin: @" << u << " busy=" << k.socket->isStillBusy());
-    int ret = close(k.socket);
 
-    return ret;
+    return close(k.socket);
 }
 
 #if ENABLE_BONDING

srtcore/api.h

@@ -337,7 +337,7 @@ class CUDTUnited
     int     epoll_release(const int eid);
 
 #if ENABLE_BONDING
-    // [[using locked(m_GlobControlLock)]]
+    SRT_ATR_NODISCARD SRT_ATTR_REQUIRES(m_GlobControlLock)
     CUDTGroup& addGroup(SRTSOCKET id, SRT_GROUP_TYPE type)
     {
         // This only ensures that the element exists.
@@ -359,7 +359,7 @@ class CUDTUnited
     void deleteGroup(CUDTGroup* g);
     void deleteGroup_LOCKED(CUDTGroup* g);
 
-    // [[using locked(m_GlobControlLock)]]
+    SRT_ATR_NODISCARD SRT_ATTR_REQUIRES(m_GlobControlLock)
     CUDTGroup* findPeerGroup_LOCKED(SRTSOCKET peergroup)
     {
         for (groups_t::iterator i = m_Groups.begin(); i != m_Groups.end(); ++i)
@@ -485,7 +485,7 @@ class CUDTUnited
         // This is only for a use together with an empty constructor.
         bool acquire(CUDTUnited& glob, CUDTSocket* s)
         {
-            bool caught = glob.acquireSocket(s);
+            const bool caught = glob.acquireSocket(s);
             socket = caught ? s : NULL;
             return caught;
         }