[vlc-devel] [PATCH 2/2] demux: adaptive: use C++ wait conditions and lock

[Steve Lhomme]

---
 modules/demux/adaptive/PlaylistManager.cpp | 42 ++++++++++------------
 modules/demux/adaptive/PlaylistManager.h   |  5 +--
 2 files changed, 22 insertions(+), 25 deletions(-)

diff --git a/modules/demux/adaptive/PlaylistManager.cpp b/modules/demux/adaptive/PlaylistManager.cpp
index 62c697e1432..13067f7589c 100644
--- a/modules/demux/adaptive/PlaylistManager.cpp
+++ b/modules/demux/adaptive/PlaylistManager.cpp
@@ -70,8 +70,6 @@ PlaylistManager::PlaylistManager( demux_t *p_demux_,
     demux.i_firstpcr = VLC_TICK_INVALID;
     vlc_mutex_init(&demux.lock);
     vlc_cond_init(&demux.cond);
-    vlc_mutex_init(&lock);
-    vlc_cond_init(&waitcond);
     vlc_mutex_init(&cached.lock);
     cached.b_live = false;
     cached.f_position = 0.0;
@@ -89,8 +87,6 @@ PlaylistManager::~PlaylistManager   ()
     delete playlist;
     delete logic;
     delete resources;
-    vlc_cond_destroy(&waitcond);
-    vlc_mutex_destroy(&lock);
     vlc_mutex_destroy(&demux.lock);
     vlc_cond_destroy(&demux.cond);
     vlc_mutex_destroy(&cached.lock);
@@ -183,10 +179,11 @@ void PlaylistManager::stop()
 {
     if(thread != nullptr)
     {
-        vlc_mutex_lock(&lock);
-        b_canceled = true;
-        vlc_cond_signal(&waitcond);
-        vlc_mutex_unlock(&lock);
+        {
+            std::lock_guard<std::mutex> lk(lock);
+            b_canceled = true;
+            waitcond.notify_one();
+        }
 
         vlc_join(thread, NULL);
         thread = nullptr;
@@ -608,21 +605,20 @@ int PlaylistManager::doControl(int i_query, va_list args)
 
 void PlaylistManager::setBufferingRunState(bool b)
 {
-    vlc_mutex_lock(&lock);
+    std::lock_guard<std::mutex> lk(lock);
     b_buffering = b;
-    vlc_cond_signal(&waitcond);
-    vlc_mutex_unlock(&lock);
+    waitcond.notify_one();
 }
 
 void PlaylistManager::Run()
 {
-    vlc_mutex_lock(&lock);
+    std::unique_lock<std::mutex> wait_lock(lock);
     const vlc_tick_t i_min_buffering = playlist->getMinBuffering();
     const vlc_tick_t i_extra_buffering = playlist->getMaxBuffering() - i_min_buffering;
     while(1)
     {
         while(!b_buffering && !b_canceled)
-            vlc_cond_wait(&waitcond, &lock);
+            waitcond.wait(wait_lock);
         if (b_canceled)
             break;
 
@@ -646,29 +642,29 @@ void PlaylistManager::Run()
 
         if(i_return != AbstractStream::buffering_lessthanmin)
         {
-            vlc_tick_t i_deadline = vlc_tick_now();
+            auto deadline = std::chrono::system_clock::now();
+
+            using namespace std::chrono_literals;
             if(i_return == AbstractStream::buffering_ongoing)
-                i_deadline += VLC_TICK_FROM_MS(10);
+                deadline += 10ms;
             else if(i_return == AbstractStream::buffering_full)
-                i_deadline += VLC_TICK_FROM_MS(100);
+                deadline += 100ms;
             else if(i_return == AbstractStream::buffering_end)
-                i_deadline += VLC_TICK_FROM_SEC(1);
+                deadline += 1000ms;
             else /*if(i_return == AbstractStream::buffering_suspended)*/
-                i_deadline += VLC_TICK_FROM_MS(250);
+                deadline += 250ms;
 
             vlc_mutex_lock(&demux.lock);
             vlc_cond_signal(&demux.cond);
             vlc_mutex_unlock(&demux.lock);
 
-            while(b_buffering &&
-                    vlc_cond_timedwait(&waitcond, &lock, i_deadline) == 0 &&
-                    i_deadline > vlc_tick_now() &&
-                    !b_canceled);
+            waitcond.wait_until(wait_lock, deadline, [this](){
+                      return !b_buffering || b_canceled;
+                  });
             if (b_canceled)
                 break;
         }
     }
-    vlc_mutex_unlock(&lock);
 }
 
 void * PlaylistManager::managerThread(void *opaque)
diff --git a/modules/demux/adaptive/PlaylistManager.h b/modules/demux/adaptive/PlaylistManager.h
index 501200f9b7a..3eece82aec5 100644
--- a/modules/demux/adaptive/PlaylistManager.h
+++ b/modules/demux/adaptive/PlaylistManager.h
@@ -25,6 +25,7 @@
 #include "logic/AbstractAdaptationLogic.h"
 #include "Streams.hpp"
 #include <vector>
+#include <condition_variable>
 
 namespace adaptive
 {
@@ -130,9 +131,9 @@ namespace adaptive
             void setBufferingRunState(bool);
             void Run();
             static void * managerThread(void *);
-            vlc_mutex_t  lock;
             vlc_thread_t thread;
-            vlc_cond_t   waitcond;
+            std::condition_variable waitcond;
+            std::mutex              lock;
             bool         b_buffering;
             bool         b_canceled;
     };
-- 
2.17.1