Remove unused osMutex code

It was never Acquire'd, only Created and Destroyed; and it was
a stub on Linux and macOS.

lib/TaskSystem.h

@@ -73,32 +73,4 @@ class osTask {
   void resume();  // resumes task
 };
 
-//	This establishes a mutual exclusion object.  once one thread locks the object,
-//	any code in another thread that contains a mutex check will block or skip that code until
-//	the locking thread unlocks it.
-class osMutex {
-#if defined(DD_ACCESS_RING)
-public:
-#else
-private:
-#endif
-
-#if defined(WIN32)
-  unsigned mutex_os_handle;
-#endif
-
-public:
-  osMutex();
-  ~osMutex();
-
-  bool Create();  // creates a mutex object.
-  void Destroy(); // destroys a mutex object
-
-  // calling thread will attempt to acquire mutex (wait until timeout in ms.) if timeout == -1, wait forever...
-  bool Acquire(int timeout = -1);
-
-  // calling thread releases control of mutex.
-  void Release();
-};
-
 #endif

lib/streamaudio.h

@@ -254,7 +254,6 @@ class AudioStream {
   int m_playbytesleft, m_playbytestotal;
   int m_curid;                  // stream's id #
   int *m_stopflag;              // location of stop flag used in stop function
-  osMutex m_loopmutex;          // stop flag is manipulated by caller and stream thread.
   bool m_loop;                  // are we looping?
   bool m_stopnextmeasure;       // stop on next measure.
   bool m_start_on_frame;        // we will play this stream on the next ::Frame call.

linux/CMakeLists.txt

@@ -3,7 +3,6 @@ SET (CPPS
   lnxcon.cpp
   lnxcon_raw.cpp
   lnxdebug.cpp
-  lnxtask.cpp
   lnxapp.cpp
   lnxcon_null.cpp
   lnxdata.cpp

mac/MACSTREAMAUDIO.CPP

@@ -475,7 +475,6 @@ bool AudioStream::Open(const char *filename, int open_flags) {
       return false;
     }
 
-    m_loopmutex.Create();
     AudioStream::SetLoopCount(1);
     m_laststate = m_state;
     mprintf((1, "opening: STRM[%d]: STOPPED sof %d\n", this->m_curid, m_start_on_frame));
@@ -497,7 +496,6 @@ void AudioStream::Close() {
     // stop the stream, close the archive, close the decoder.
     AudioStream::Stop();
     m_archive.Close();
-    m_loopmutex.Destroy();
     m_curid = -1;
 
     // free streaming buffers and decoder if we need to.

stream_audio/streamaudio.cpp

@@ -368,7 +368,6 @@ bool AudioStream::Open(const char *filename, int open_flags) {
     if (!AudioStream::ReopenDigitalStream(0, nbufs)) {
       return false;
     }
-    m_loopmutex.Create();
     AudioStream::SetLoopCount(1);
     m_laststate = m_state;
     m_state = STRM_STOPPED;
@@ -383,7 +382,6 @@ void AudioStream::Close() {
     // stop the stream, close the archive, close the decoder.
     AudioStream::Stop();
     m_archive.Close();
-    m_loopmutex.Destroy();
     m_curid = -1;
     // free streaming buffers and decoder if we need to.
     for (i = 0; i < STRM_BUFCOUNT; i++) {

win32/wintask.cpp

@@ -131,52 +131,3 @@ bool osEvent::error() const {
   else
     return 0;
 }
-
-//	This establishes a mutual exclusion object.  once one thread locks the object,
-//	any code in another thread that contains a mutex check will block or skip that code until
-//	the locking thread unlocks it.
-osMutex::osMutex() { mutex_os_handle = 0; }
-
-osMutex::~osMutex() { Destroy(); }
-
-bool osMutex::Create() // creates a mutex object.
-{
-  if (!mutex_os_handle) {
-    mutex_os_handle = (unsigned)CreateMutex(NULL, FALSE, NULL);
-    return mutex_os_handle ? true : false;
-  }
-
-  return false;
-}
-
-void osMutex::Destroy() // destroys a mutex object
-{
-  if (mutex_os_handle) {
-    CloseHandle((HANDLE)mutex_os_handle);
-    mutex_os_handle = 0;
-  }
-}
-
-// calling thread will attempt to acquire mutex (wait until timeout) if timeout == -1, wait forever...
-bool osMutex::Acquire(int timeout) {
-  DWORD res;
-
-  if (!mutex_os_handle)
-    return true; // we should return true because the caller will skip code if false is returned.
-
-  if (timeout == -1)
-    timeout = INFINITE;
-
-  res = WaitForSingleObject((HANDLE)mutex_os_handle, timeout);
-  if (res == WAIT_OBJECT_0 || res == WAIT_ABANDONED)
-    return true;
-  else
-    return false;
-}
-
-// calling thread releases control of mutex.
-void osMutex::Release() {
-  if (mutex_os_handle) {
-    ReleaseMutex((HANDLE)mutex_os_handle);
-  }
-}