Update the xineScope to remove global variables.

This patch updates xineScope.c to better align with Amarok's code. As a
result, the analyzer is more accurate.  For instance, when playing an
audio file and there is a silent spot, the blocks will correctly "drop"
to the bottom, leaving an empty analyzer.  The previous behaviour would
leave some blocks "stuck" in their position

See: TDE/codeine#23
Signed-off-by: mio <[email protected]>
(cherry picked from commit ff2a5768dd4d199cb8bbbe2af4ea3fbb68a489f3)

4 files changed, 141 insertions, 56 deletions

diff --git a/src/app/xineEngine.cpp b/src/app/xineEngine.cpp
index 2cb9cd3..7f73e0d 100644
--- a/src/app/xineEngine.cpp
+++ b/src/app/xineEngine.cpp
@@ -36,8 +36,9 @@ VideoWindow::VideoWindow( TQWidget *parent )
       , m_eventQueue( nullptr )
       , m_videoPort( nullptr )
       , m_audioPort( nullptr )
-      , m_scope( nullptr )
+      , m_post( nullptr )
       , m_xine( nullptr )
+      , m_scope( Analyzer::SCOPE_SIZE * 2 ) // Multiply by two to account for interleaved PCM.
       , m_current_vpts( 0 )
 {
    DEBUG_BLOCK
@@ -51,10 +52,6 @@ VideoWindow::VideoWindow( TQWidget *parent )
    setPaletteBackgroundColor( TQt::black );
    setFocusPolicy( ClickFocus );
 
-   //TODO sucks
-   //TODO namespace this?
-   myList->next = myList; //init the buffer list
-
    // Detect xine version, this is used for volume adjustment.
    // Xine versions prior to 1.2.13 use linear volume, so the engine uses logarithmic volume.
    // Xine versions starting from 1.2.13 use logarithmic volume, so the engine uses linear volume.
@@ -101,7 +98,7 @@ VideoWindow::~VideoWindow()
    if( m_stream )     xine_dispose( m_stream );
    if( m_audioPort )  xine_close_audio_driver( m_xine, m_audioPort );
    if( m_videoPort )  xine_close_video_driver( m_xine, m_videoPort );
-   if( m_scope )      xine_post_dispose( m_xine, m_scope );
+   if( m_post )       xine_post_dispose( m_xine, m_post );
    if( m_xine )       xine_exit( m_xine );
 
    cleanUpVideo();
@@ -119,7 +116,7 @@ VideoWindow::init()
    if( !m_xine )
       return false;
 
-   xine_engine_set_param( m_xine, XINE_ENGINE_PARAM_VERBOSITY, 99 );
+   xine_engine_set_param(m_xine, XINE_ENGINE_PARAM_VERBOSITY, XINE_VERBOSITY_DEBUG);
 
    debug() << "xine_config_load()\n";
    xine_config_load( m_xine, TQFile::encodeName( TQDir::homeDirPath() + "/.xine/config" ) );
@@ -161,9 +158,9 @@ VideoWindow::init()
    debug() << "scope_plugin_new()\n";
 #if XINE_MAJOR_VERSION > 1 || (XINE_MAJOR_VERSION == 1 && XINE_MINOR_VERSION > 2) || \
    (XINE_MAJOR_VERSION == 1 && XINE_MINOR_VERSION == 2 && XINE_SUB_VERSION >= 10)
-   m_scope = xine_post_init( m_xine, "codeine-scope", 1, &m_audioPort, nullptr );
+   m_post = xine_post_init( m_xine, "codeine-scope", 1, &m_audioPort, nullptr );
 #else
-   m_scope = scope_plugin_new( m_xine, m_audioPort );
+   m_post = scope_plugin_new( m_xine, m_audioPort );
 
    //FIXME this one seems to make seeking unstable for Codeine, perhaps
    xine_set_param( m_stream, XINE_PARAM_METRONOM_PREBUFFER, 6000 ); //less buffering, faster seeking..
@@ -281,9 +278,9 @@ VideoWindow::load( const KURL &url )
       // FIXME leaves one erroneous buffer
       timerEvent( nullptr );
 
-      if( m_scope ) {
+      if( m_post ) {
          xine_post_out_t *source = xine_get_audio_source( m_stream );
-         xine_post_in_t  *target = (xine_post_in_t*)xine_post_input( m_scope, const_cast<char*>("audio in") );
+         xine_post_in_t  *target = (xine_post_in_t*)xine_post_input( m_post, const_cast<char*>("audio in") );
          xine_post_wire( source, target );
       }
 
@@ -373,6 +370,8 @@ VideoWindow::stop()
 {
    xine_stop( m_stream );
 
+   std::fill(m_scope.begin(), m_scope.end(), 0);
+
    announceStateChange();
 }
 
@@ -590,7 +589,7 @@ VideoWindow::setStreamParameter( int value )
    else if( sender == "volume" )
    {
       parameter = XINE_PARAM_AUDIO_AMP_LEVEL;
-      value = 100 - value; // TQt sliders are wrong way round when vertical
+      value = 100 - value; // TQt sliders are the wrong way round when vertical
       if (s_logarithmicVolume)
       {
         value = makeVolumeLogarithmic(value);
@@ -607,16 +606,25 @@ VideoWindow::scope()
 {
    using Analyzer::SCOPE_SIZE;
 
-   static Engine::Scope scope( SCOPE_SIZE );
+   if (!m_post || !m_stream || xine_get_status(m_stream) != XINE_STATUS_PLAY)
+   {
+      return m_scope;
+   }
 
-   if( xine_get_status( m_stream ) != XINE_STATUS_PLAY )
-      return scope;
+   MyNode *const myList        = scope_plugin_list(m_post);
+   const int64_t pts_per_smpls = scope_plugin_pts_per_smpls(m_post);
+   const int channels          = scope_plugin_channels(m_post);
+   int scopeIdx = 0;
+
+   if (channels > 2)
+   {
+      return m_scope;
+   }
 
    //prune the buffer list and update the m_current_vpts timestamp
    timerEvent( nullptr );
 
-   const int64_t pts_per_smpls = scope_plugin_pts_per_smpls(m_scope);
-   for( int channels = xine_get_stream_info( m_stream, XINE_STREAM_INFO_AUDIO_CHANNELS ), frame = 0; frame < SCOPE_SIZE; )
+   for (int n, frame = 0; frame < SCOPE_SIZE; /* no-op */)
    {
       MyNode *best_node = nullptr;
 
@@ -637,10 +645,10 @@ VideoWindow::scope()
       data16  = best_node->mem;
       data16 += diff;
 
-      diff += diff % channels; //important correction to ensure we don't overflow the buffer
-      diff /= channels;
+      diff += diff % channels; // important correction to ensure we don't overflow the buffer.
+      diff /= channels;        // use units of frames, not samples.
 
-      int
+      // calculate the number of available samples in this buffer.
       n  = best_node->num_frames;
       n -= diff;
       n += frame; //clipping for # of frames we need
@@ -650,33 +658,52 @@ VideoWindow::scope()
 
       for( int a, c; frame < n; ++frame, data16 += channels ) {
          for( a = c = 0; c < channels; ++c )
-            a += data16[c];
-
-         a /= channels;
-         scope[frame] = a;
+         {
+            // now we give interleaved PCM to the scope.
+            m_scope[scopeIdx++] = data16[c];
+            if (channels == 1)
+            {
+               // Duplicate mono samples.
+               m_scope[scopeIdx++] = data16[c];
+            }
+         }
       }
 
       m_current_vpts = best_node->vpts_end;
       m_current_vpts++; //FIXME needs to be done for some reason, or you get situations where it uses same buffer again and again
    }
 
-   return scope;
+   return m_scope;
 }
 
 void
 VideoWindow::timerEvent( TQTimerEvent* )
 {
+   if (!m_stream)
+   {
+      return;
+   }
+
    /// here we prune the buffer list regularly
-   MyNode * const first_node = myList->next;
-   MyNode const * const list_end = myList;
+   MyNode *myList = scope_plugin_list(m_post);
+
+   if (!myList)
+   {
+      return;
+   }
+
+   // We operate on a subset of the list for thread-safety.
+   MyNode *const firstNode = myList->next;
+   const MyNode *const listEnd = myList;
 
+   // If we're not playing or paused, empty the list.
    m_current_vpts = (xine_get_status( m_stream ) == XINE_STATUS_PLAY)
          ? xine_get_current_vpts( m_stream )
          : std::numeric_limits<int64_t>::max();
 
-   for( MyNode *prev = first_node, *node = first_node->next; node != list_end; node = node->next )
+   for( MyNode *prev = firstNode, *node = firstNode->next; node != listEnd; node = node->next )
    {
-      // we never delete first_node
+      // we never delete firstNode
       // this maintains thread-safety
       if( node->vpts_end < m_current_vpts ) {
          prev->next = node->next;
diff --git a/src/app/xineEngine.h b/src/app/xineEngine.h
index 6f8170a..168080d 100644
--- a/src/app/xineEngine.h
+++ b/src/app/xineEngine.h
@@ -104,9 +104,10 @@ namespace Codeine
       xine_event_queue_t *m_eventQueue;
       xine_video_port_t  *m_videoPort;
       xine_audio_port_t  *m_audioPort;
-      xine_post_t        *m_scope;
+      xine_post_t        *m_post;
       xine_t             *m_xine;
 
+      Engine::Scope m_scope;
       int64_t m_current_vpts;
 
       KURL m_url;
diff --git a/src/app/xineScope.c b/src/app/xineScope.c
index 3e7cb69..55cf026 100644
--- a/src/app/xineScope.c
+++ b/src/app/xineScope.c
@@ -4,16 +4,38 @@
 /* need access to port_ticket */
 #define XINE_ENGINE_INTERNAL
 
+#define LOG_MODULE "codine-scope"
+#define LOG_LEVEL LOG_LEVEL_DEBUG
+// #define LOG
+
 #include "xineScope.h"
 #include <xine/post.h>
 #include <xine/xine_internal.h>
 
+typedef struct scope_plugin_s {
+   post_plugin_t super;
+   int channels;
+   int64_t pts_per_smpls;
+   MyNode *list;
+} scope_plugin_t;
 
-static MyNode theList;
-static int myChannels = 0;
-static int64_t pts_per_smpls;
+int scope_plugin_channels(void *post)
+{
+   scope_plugin_t *self = post;
+   return self->channels;
+}
 
-MyNode* const myList = &theList;
+MyNode *scope_plugin_list(void *post)
+{
+   scope_plugin_t *self = post;
+   return self->list;
+}
+
+int64_t scope_plugin_pts_per_smpls(void *post)
+{
+   scope_plugin_t *self = post;
+   return self->pts_per_smpls;
+}
 
 /*************************
 * post plugin functions *
@@ -22,7 +44,10 @@ MyNode* const myList = &theList;
 static int
 scope_port_open( xine_audio_port_t *port_gen, xine_stream_t *stream, uint32_t bits, uint32_t rate, int mode )
 {
+   lprintf("scope_port_open()\n");
+
    post_audio_port_t *port = (post_audio_port_t *)port_gen;
+   scope_plugin_t *self = (scope_plugin_t *)port->post;
 
    _x_post_rewire( (post_plugin_t*)port->post );
    _x_post_inc_usage( port );
@@ -32,14 +57,14 @@ scope_port_open( xine_audio_port_t *port_gen, xine_stream_t *stream, uint32_t bi
    port->rate = rate;
    port->mode = mode;
 
-   myChannels = _x_ao_mode2channels( mode );
+   self->channels = _x_ao_mode2channels(mode);
 
    int ret = port->original_port->open( port->original_port, stream, bits, rate, mode );
 #if XINE_MAJOR_VERSION > 1 || (XINE_MAJOR_VERSION == 1 && XINE_MINOR_VERSION > 2) || \
    (XINE_MAJOR_VERSION == 1 && XINE_MINOR_VERSION == 2 && XINE_SUB_VERSION >= 10)
-   pts_per_smpls = ((uint32_t)90000 * (uint32_t)32768) / rate;
+   self->pts_per_smpls = ((uint32_t)90000 * (uint32_t)32768) / rate;
 #else
-   pts_per_smpls = stream->metronom->pts_per_smpls;
+   self->pts_per_smpls = stream->metronom->pts_per_smpls;
 #endif
    return ret;
 }
@@ -47,7 +72,17 @@ scope_port_open( xine_audio_port_t *port_gen, xine_stream_t *stream, uint32_t bi
 static void
 scope_port_close( xine_audio_port_t *port_gen, xine_stream_t *stream )
 {
+   lprintf("scope_port_close()\n");
+
    post_audio_port_t *port = (post_audio_port_t *)port_gen;
+   scope_plugin_t *self = (scope_plugin_t *)port->post;
+
+   /* ensure the buffers are deleted during the next VideoWindow::timerEvent */
+   MyNode *node;
+   for (node = self->list->next; node != self->list; node = node->next)
+   {
+      node->vpts = node->vpts_end - 1;
+   }
 
    port->stream = NULL;
    port->original_port->close( port->original_port, stream );
@@ -59,6 +94,7 @@ static void
 scope_port_put_buffer( xine_audio_port_t *port_gen, audio_buffer_t *buf, xine_stream_t *stream )
 {
    post_audio_port_t *port = (post_audio_port_t *)port_gen;
+   scope_plugin_t *self = (scope_plugin_t *)port->post;
 
    /* we are too simple to handle 8bit */
    /* what does it mean when stream == NULL? */
@@ -66,7 +102,7 @@ scope_port_put_buffer( xine_audio_port_t *port_gen, audio_buffer_t *buf, xine_st
       port->original_port->put_buffer( port->original_port, buf, stream ); return; }
 
    MyNode *new_node;
-   const int num_samples = buf->num_frames * myChannels;
+   const int num_samples = buf->num_frames * self->channels;
 
    new_node             = malloc( sizeof(MyNode) );
 #ifdef METRONOM_VPTS
@@ -80,7 +116,7 @@ scope_port_put_buffer( xine_audio_port_t *port_gen, audio_buffer_t *buf, xine_st
 
    {
       int64_t
-      K  = pts_per_smpls; /*smpls = 1<<16 samples*/
+      K  = self->pts_per_smpls; /*smpls = 1<<16 samples*/
       K *= num_samples;
       K /= (1<<16);
       K += new_node->vpts;
@@ -93,14 +129,29 @@ scope_port_put_buffer( xine_audio_port_t *port_gen, audio_buffer_t *buf, xine_st
 
    /* finally we should append the current buffer to the list
    * NOTE this is thread-safe due to the way we handle the list in the GUI thread */
-   new_node->next = myList->next;
-   myList->next   = new_node;
+   new_node->next     = self->list->next;
+   self->list->next   = new_node;
 }
 
 static void
 scope_dispose( post_plugin_t *this )
 {
-   free( this );
+   MyNode *list = ((scope_plugin_t *)this)->list;
+   MyNode *prev;
+   MyNode *node = list;
+
+   /* Free all elements of the list (a ring buffer) */
+   do
+   {
+      prev = node->next;
+
+      free(node->mem);
+      free(node);
+
+      node = prev;
+   } while(node != list);
+
+   free(this);
 }
 
 
@@ -118,15 +169,15 @@ xine_post_t* scope_plugin_new( xine_t *xine, xine_audio_port_t *audio_target )
    if( audio_target == NULL )
       return NULL;
 
-   post_plugin_t *post_plugin = calloc( 1, sizeof(post_plugin_t) );
+   scope_plugin_t *scope_plugin = calloc(1, sizeof(scope_plugin_t));
+   post_plugin_t *post_plugin = (post_plugin_t *)scope_plugin;
 
    {
-      post_plugin_t     *this = post_plugin;
       post_in_t         *input;
       post_out_t        *output;
       post_audio_port_t *port;
 
-      _x_post_init( this, 1, 0 );
+      _x_post_init(post_plugin, 1, 0);
 
 #if XINE_MAJOR_VERSION > 1 || (XINE_MAJOR_VERSION == 1 && XINE_MINOR_VERSION > 2) || \
    (XINE_MAJOR_VERSION == 1 && XINE_MINOR_VERSION == 2 && XINE_SUB_VERSION >= 10)
@@ -138,10 +189,10 @@ xine_post_t* scope_plugin_new( xine_t *xine, xine_audio_port_t *audio_target )
       port->new_port.close      = scope_port_close;
       port->new_port.put_buffer = scope_port_put_buffer;
 
-      this->xine_post.audio_input[0] = &port->new_port;
-      this->xine_post.type = PLUGIN_POST;
+      post_plugin->xine_post.audio_input[0] = &port->new_port;
+      post_plugin->xine_post.type = PLUGIN_POST;
 
-      this->dispose = scope_dispose;
+      post_plugin->dispose = scope_dispose;
    }
 
 #if XINE_MAJOR_VERSION < 1 || (XINE_MAJOR_VERSION == 1 && XINE_MINOR_VERSION < 2) || \
@@ -153,6 +204,12 @@ xine_post_t* scope_plugin_new( xine_t *xine, xine_audio_port_t *audio_target )
    post_plugin->xine = xine;
 #endif
 
+   /* scope_plugin_t init */
+   scope_plugin->channels = 0;
+   scope_plugin->pts_per_smpls = 0;
+   scope_plugin->list = calloc(1, sizeof(MyNode));
+   scope_plugin->list->next = scope_plugin->list;
+
 #if XINE_MAJOR_VERSION > 1 || (XINE_MAJOR_VERSION == 1 && XINE_MINOR_VERSION > 2) || \
    (XINE_MAJOR_VERSION == 1 && XINE_MINOR_VERSION == 2 && XINE_SUB_VERSION >= 10)
    return post_plugin;
@@ -161,11 +218,6 @@ xine_post_t* scope_plugin_new( xine_t *xine, xine_audio_port_t *audio_target )
 #endif
 }
 
-int64_t scope_plugin_pts_per_smpls( void *post )
-{
-		return pts_per_smpls;
-}
-
 #if XINE_MAJOR_VERSION > 1 || (XINE_MAJOR_VERSION == 1 && XINE_MINOR_VERSION > 2) || \
    (XINE_MAJOR_VERSION == 1 && XINE_MINOR_VERSION == 2 && XINE_SUB_VERSION >= 10)
 static void *scope_init_plugin(xine_t *xine, const void *data)
diff --git a/src/app/xineScope.h b/src/app/xineScope.h
index 623d56d..99d7215 100644
--- a/src/app/xineScope.h
+++ b/src/app/xineScope.h
@@ -33,18 +33,23 @@ struct my_node_s
     int64_t  vpts_end;
 };
 
-extern MyNode* const myList;
-
 #ifdef __cplusplus
 extern "C"
 {
+#endif
+
 #if XINE_MAJOR_VERSION > 1 || (XINE_MAJOR_VERSION == 1 && XINE_MINOR_VERSION > 2) || \
    (XINE_MAJOR_VERSION == 1 && XINE_MINOR_VERSION == 2 && XINE_SUB_VERSION >= 10)
     extern const plugin_info_t scope_plugin_info[];
 #else
     xine_post_t* scope_plugin_new( xine_t*, xine_audio_port_t* );
 #endif
-    int64_t scope_plugin_pts_per_smpls( void* );
+
+    int      scope_plugin_channels(void *);
+    MyNode  *scope_plugin_list(void *);
+    int64_t  scope_plugin_pts_per_smpls(void *);
+
+#ifdef __cplusplus
 }
 #endif