Make PaStream a stronger type

This changes PaStream* from a pointer to void to a pointer to an
undefined, but unique type. This ensures functions that take a PaStream*
reject incompatible types, for improved type safety.

While this is technically an API change, it is unlikely to break anyone
as it's unlikely user code depends on this type being void specifically
(unless they suffer from the bugs that this change is designed to
prevent!).

Fixes PortAudio#915

include/portaudio.h

@@ -636,7 +636,7 @@ PaError Pa_IsFormatSupported( const PaStreamParameters *inputParameters,
  Pa_GetStreamTime, Pa_GetStreamCpuLoad
 
 */
-typedef void PaStream;
+typedef struct PaStream PaStream;
 
 
 /** Can be passed as the framesPerBuffer parameter to Pa_OpenStream()

src/common/pa_front.c

@@ -346,7 +346,7 @@ static void CloseOpenStreams( void )
         logic is used for automatically closed streams */
 
     while( firstOpenStream_ != NULL )
-        Pa_CloseStream( firstOpenStream_ );
+        Pa_CloseStream( (PaStream*)firstOpenStream_ );
 }
 
 

src/hostapi/alsa/pa_linux_alsa.c

@@ -3029,7 +3029,7 @@ static PaError StartStream( PaStream *s )
 error:
     if( streamStarted )
     {
-        AbortStream( stream );
+        AbortStream( (PaStream*)stream );
     }
     stream->isActive = 0;
 
@@ -4549,7 +4549,7 @@ static PaError WriteStream( PaStream* s, const void *buffer, unsigned long frame
         /* Start stream after one period of samples worth */
 
         /* Frames residing in buffer */
-        PA_ENSURE( err = GetStreamWriteAvailable( stream ) );
+        PA_ENSURE( err = GetStreamWriteAvailable( (PaStream*)stream ) );
         framesAvail = err;
         hwAvail = stream->playback.alsaBufferSize - framesAvail;
 

src/hostapi/coreaudio/pa_mac_core.c

@@ -2088,7 +2088,7 @@ static PaError OpenStream( struct PaUtilHostApiRepresentation *hostApi,
     return result;
 
 error:
-    CloseStream( stream );
+    CloseStream( (PaStream*)stream );
     return result;
 }
 

src/hostapi/jack/pa_jack.c

@@ -1756,7 +1756,7 @@ static PaError RealStop( PaJackStream *stream, int abort )
     int i;
 
     if( stream->isBlockingStream )
-        BlockingWaitEmpty ( stream );
+        BlockingWaitEmpty ( (PaStream*)stream );
 
     ASSERT_CALL( pthread_mutex_lock( &stream->hostApi->mtx ), 0 );
     if( abort )

src/hostapi/pulseaudio/pa_linux_pulseaudio_cb.c

@@ -881,7 +881,7 @@ PaError PaPulseAudio_StartStreamCb( PaStream * s )
 
     if( pulseaudioPlaybackStarted || pulseaudioRecordStarted )
     {
-        PaPulseAudio_AbortStreamCb( stream );
+        PaPulseAudio_AbortStreamCb( (PaStream*)stream );
     }
 
     stream->isActive = 0;

src/hostapi/sndio/pa_sndio.c

@@ -417,7 +417,7 @@ static PaError OpenStream( struct PaUtilHostApiRepresentation *hostApi, PaStream
     sndioStream->mode = mode;
     sndioStream->hdl = hdl;
     sndioStream->par = par;
-    *paStream = sndioStream;
+    *paStream = (PaStream*)sndioStream;
     PA_DEBUG( ( "OpenStream: done\n" ) );
     return paNoError;
 }

src/hostapi/wasapi/pa_win_wasapi.c

@@ -4134,7 +4134,7 @@ static PaError OpenStream( struct PaUtilHostApiRepresentation *hostApi,
 error:
 
     if (stream != NULL)
-        CloseStream(stream);
+        CloseStream((PaStream*)stream);
 
     return result;
 }