Make libmythfreesurround thread-safe and allowing more than one insta…

…nce of it...

Was way too complicated for its own good. so what if we need to reallocate memory during creation.. Happens only very occasionally.

mythtv/libs/libmythfreesurround/freesurround.cpp

@@ -47,63 +47,6 @@ static const float m7db = 0.44721359549996;              // 7dB  = SQRT(5)
 
 unsigned int block_size = default_block_size;
 
-// stupidity countermeasure...
-template<class T> T pop_back(std::list<T> &l)
-{
-    T result(l.back());
-    l.pop_back();
-    return result;
-}
-
-// a pool, where the DSP can throw its objects at after it got deleted and
-// get them back when it is recreated...
-class object_pool
-{
-public:
-    typedef void* (*callback)();
-    typedef void* (*dcallback)(void*);
-    // initialize
-    object_pool(callback cbf, dcallback dbf):construct(cbf), destruct(dbf) { }
-    ~object_pool()
-    {
-        for (std::map<void*,void*>::iterator i=pool.begin(),e=pool.end();
-             i != e; i++)
-            destruct(i->second);
-        for (std::list<void*>::iterator i=freelist.begin(),e=freelist.end();
-             i != e; i++)
-            destruct(*i);
-    }
-    // (re)acquire an object
-    void *acquire(void *who)
-    {
-        std::map<void*,void*>::iterator i(pool.find(who));
-        if (i != pool.end())
-            return i->second;
-        else
-            if (!freelist.empty())
-                return pool.insert(std::make_pair(who,pop_back(freelist)))
-                                  .first->second;
-            else
-                return pool.insert(std::make_pair(who,construct()))
-                                  .first->second;
-    }
-    // release an object into the wild
-    void release(void *who)
-    {
-        std::map<void*,void*>::iterator i(pool.find(who));
-        if (i != pool.end()) {
-            freelist.push_back(i->second);
-            pool.erase(i);
-        }
-    }
-public:
-    callback construct;            // object constructor callback
-    dcallback destruct;            // object destructor callback
-    std::list<void*> freelist;     // list of available objects
-    std::map<void*,void*> pool;    // pool of used objects, by class
-};
-
-// buffers which we usually need (and want to share between plugin lifespans)
 struct buffers
 {
     buffers(unsigned int s):
@@ -124,23 +67,6 @@ struct buffers
                        rls, rrs;       // for demultiplexing
 };
 
-// construction methods
-void *new_decoder() { return new fsurround_decoder(block_size); }
-void *new_buffers() { return new buffers(block_size/2); }
-void *delete_decoder(void *_p)
-{
-    fsurround_decoder *p = static_cast<fsurround_decoder*>(_p);
-    delete p;
-}
-void *delete_buffers(void *_p)
-{
-    buffers *p = static_cast<buffers*>(_p);
-    delete p;
-}
-
-object_pool dp(&new_decoder, &delete_decoder);
-object_pool bp(&new_buffers, &delete_buffers);
-
 //#define SPEAKERTEST
 #ifdef SPEAKERTEST
 int channel_select = -1;
@@ -186,7 +112,7 @@ FreeSurround::FreeSurround(uint srate, bool moviemode, SurroundMode smode) :
             break;
     }
 
-    bufs = (buffers*)bp.acquire((void*)1);
+    bufs = new buffers(block_size/2);
     open();
 #ifdef SPEAKERTEST
     channel_select++;
@@ -226,11 +152,8 @@ FreeSurround::~FreeSurround()
 {
     LOG(VB_AUDIO, LOG_DEBUG, QString("FreeSurround::~FreeSurround"));
     close();
-    if (bufs)
-    {
-        bp.release((void*)1);
-        bufs = NULL;
-    }
+    delete bufs;
+    bufs = NULL;
     LOG(VB_AUDIO, LOG_DEBUG, QString("FreeSurround::~FreeSurround done"));
 }
 
@@ -519,7 +442,7 @@ void FreeSurround::open()
 {
     if (!decoder)
     {
-        decoder = (fsurround_decoder*)dp.acquire((void*)1);
+        decoder = new fsurround_decoder(block_size);
         decoder->flush();
         if (bufs)
             bufs->clear();
@@ -530,11 +453,8 @@ void FreeSurround::open()
 
 void FreeSurround::close()
 {
-    if (decoder)
-    {
-        dp.release((void*)1);
-        decoder = 0;
-    }
+    delete decoder;
+    decoder = NULL;
 }
 
 uint FreeSurround::numUnprocessedFrames()