Import.cpp does not depend on subclasses of ImportPlugin...

... freeing 15 files from the big strongly connected component:

ImportFFmpeg & ODDecodeFFMpegTask (still in a cycle of two)
ImportFLAC
ImportGStreamer
ImportLOF
ImportMIDI
ImportMP3
ImportOGG
ImportPCM
ImportQT
ProjectFileManager
ProjectFSCK
ProjectManager
ProjectSelectionManager
ODDecodeFlacTask

And eight header files in src/import are deleted.

This breaks a lot of cycles because Import, which is still in the big component,
no longer includes ImportLOF, which recursively uses ProjectManager. A
registration system for the subclasses of ImportFileHandle allows that
recursion without the cyclic compilation dependencies.

src/import/Import.cpp

@@ -38,6 +38,8 @@ and ImportLOF.cpp.
 #include "../Audacity.h" // for USE_* macros
 #include "Import.h"
 
+#include "ImportPlugin.h"
+
 #include <algorithm>
 
 #include <wx/textctrl.h>
@@ -51,14 +53,6 @@ and ImportLOF.cpp.
 #include "../Project.h"
 #include "../WaveTrack.h"
 
-#include "ImportPCM.h"
-#include "ImportMP3.h"
-#include "ImportOGG.h"
-#include "ImportQT.h"
-#include "ImportLOF.h"
-#include "ImportFLAC.h"
-#include "ImportFFmpeg.h"
-#include "ImportGStreamer.h"
 #include "../Prefs.h"
 
 #include "../widgets/ProgressDialog.h"
@@ -83,30 +77,52 @@ Importer::~Importer()
 {
 }
 
+ImportPluginList &Importer::sImportPluginList()
+{
+   static ImportPluginList theList;
+   return theList;
+}
+
+Importer::RegisteredImportPlugin::RegisteredImportPlugin(
+   std::unique_ptr<ImportPlugin> pPlugin )
+{
+   if ( pPlugin )
+      sImportPluginList().emplace_back( std::move( pPlugin ) );
+}
+
+UnusableImportPluginList &Importer::sUnusableImportPluginList()
+{
+   static UnusableImportPluginList theList;
+   return theList;
+}
+
+Importer::RegisteredUnusableImportPlugin::RegisteredUnusableImportPlugin(
+   std::unique_ptr<UnusableImportPlugin> pPlugin )
+{
+   if ( pPlugin )
+      sUnusableImportPluginList().emplace_back( std::move( pPlugin ) );
+}
+
 bool Importer::Initialize()
 {
-   ImportPluginList{}.swap(mImportPluginList);
-   UnusableImportPluginList{}.swap(mUnusableImportPluginList);
-   ExtImportItems{}.swap(mExtImportItems);
-
    // build the list of import plugin and/or unusableImporters.
    // order is significant.  If none match, they will all be tried
    // in the order defined here.
-   GetPCMImportPlugin(mImportPluginList, mUnusableImportPluginList);
-   GetOGGImportPlugin(mImportPluginList, mUnusableImportPluginList);
-   GetFLACImportPlugin(mImportPluginList, mUnusableImportPluginList);
-   GetMP3ImportPlugin(mImportPluginList, mUnusableImportPluginList);
-   GetLOFImportPlugin(mImportPluginList, mUnusableImportPluginList);
 
-   #if defined(USE_FFMPEG)
-   GetFFmpegImportPlugin(mImportPluginList, mUnusableImportPluginList);
-   #endif
-   #ifdef USE_QUICKTIME
-   GetQTImportPlugin(mImportPluginList, mUnusableImportPluginList);
-   #endif
-   #if defined(USE_GSTREAMER)
-   GetGStreamerImportPlugin(mImportPluginList, mUnusableImportPluginList);
-   #endif
+   // They were pushed on the array at static initialization time in an
+   // unspecified sequence.  Sort according to the sequence numbers they
+   // report to make the order determinate.
+   auto &list = sImportPluginList();
+   std::sort( list.begin(), list.end(),
+      []( const ImportPluginList::value_type &a,
+          const ImportPluginList::value_type &b ){
+         return a->SequenceNumber() < b->SequenceNumber();
+      }
+   );
+
+   // Ordering of the unusable plugin list is not important.
+
+   ExtImportItems{}.swap(mExtImportItems);
 
    ReadImportItems();
 
@@ -116,15 +132,13 @@ bool Importer::Initialize()
 bool Importer::Terminate()
 {
    WriteImportItems();
-   ImportPluginList{}.swap( mImportPluginList );
-   UnusableImportPluginList{}.swap( mUnusableImportPluginList );
 
    return true;
 }
 
 void Importer::GetSupportedImportFormats(FormatList *formatList)
 {
-   for(const auto &importPlugin : mImportPluginList)
+   for(const auto &importPlugin : sImportPluginList())
    {
       formatList->emplace_back(importPlugin->GetPluginFormatDescription(),
                                importPlugin->GetSupportedExtensions());
@@ -206,7 +220,7 @@ void Importer::ReadImportItems()
       for (size_t i = 0; i < new_item->filters.size(); i++)
       {
          bool found = false;
-         for (const auto &importPlugin : mImportPluginList)
+         for (const auto &importPlugin : sImportPluginList())
          {
             if (importPlugin->GetPluginStringID() == new_item->filters[i])
             {
@@ -220,7 +234,7 @@ void Importer::ReadImportItems()
            new_item->filter_objects.push_back(nullptr);
       }
       /* Find all filter objects that are not present in the filter list */
-      for (const auto &importPlugin : mImportPluginList)
+      for (const auto &importPlugin : sImportPluginList())
       {
          bool found = false;
          for (size_t i = 0; i < new_item->filter_objects.size(); i++)
@@ -317,7 +331,7 @@ std::unique_ptr<ExtImportItem> Importer::CreateDefaultImportItem()
    new_item->extensions.push_back(wxT("*"));
    new_item->mime_types.push_back(wxT("*"));
 
-   for (const auto &importPlugin : mImportPluginList)
+   for (const auto &importPlugin : sImportPluginList())
    {
       new_item->filters.push_back(importPlugin->GetPluginStringID());
       new_item->filter_objects.push_back(importPlugin.get());
@@ -371,7 +385,7 @@ bool Importer::Import(const FilePath &fName,
 
    if (usersSelectionOverrides)
    {
-      for (const auto &plugin : mImportPluginList)
+      for (const auto &plugin : sImportPluginList())
       {
          if (plugin->GetPluginFormatDescription().CompareTo(type) == 0)
          {
@@ -441,16 +455,16 @@ bool Importer::Import(const FilePath &fName,
 
    // Add all plugins that support the extension
 
-   // Here we rely on the fact that the first plugin in mImportPluginList is libsndfile.
+   // Here we rely on the fact that the first plugin in sImportPluginList() is libsndfile.
    // We want to save this for later insertion ahead of libmad, if libmad supports the extension.
-   // The order of plugins in mImportPluginList is determined by the Importer constructor alone and
+   // The order of plugins in sImportPluginList() is determined by the Importer constructor alone and
    // is not changed by user selection overrides or any other mechanism, but we include an assert
    // in case subsequent code revisions to the constructor should break this assumption that
    // libsndfile is first.
-   ImportPlugin *libsndfilePlugin = mImportPluginList.begin()->get();
+   ImportPlugin *libsndfilePlugin = sImportPluginList().begin()->get();
    wxASSERT(libsndfilePlugin->GetPluginStringID() == wxT("libsndfile"));
 
-   for (const auto &plugin : mImportPluginList)
+   for (const auto &plugin : sImportPluginList())
    {
       // Make sure its not already in the list
       if (importPlugins.end() ==
@@ -486,7 +500,7 @@ bool Importer::Import(const FilePath &fName,
    // Otherwise, if FFmpeg (libav) has not been installed, libmad will still be there near the
    // end of the preference list importPlugins, where it will claim success importing FFmpeg file
    // formats unsuitable for it, and produce distorted results.
-   for (const auto &plugin : mImportPluginList)
+   for (const auto &plugin : sImportPluginList())
    {
       if (!(plugin->GetPluginStringID() == wxT("libmad")))
       {
@@ -565,7 +579,7 @@ bool Importer::Import(const FilePath &fName,
    // None of our plugins can handle this file.  It might be that
    // Audacity supports this format, but support was not compiled in.
    // If so, notify the user of this fact
-   for (const auto &unusableImportPlugin : mUnusableImportPluginList)
+   for (const auto &unusableImportPlugin : sUnusableImportPluginList())
    {
       if( unusableImportPlugin->SupportsExtension(extension) )
       {

src/import/Import.h

@@ -88,6 +88,19 @@ class ExtImportItem
 
 class Importer {
 public:
+
+   // Objects of this type are statically constructed in files implementing
+   // subclasses of ImportPlugin
+   struct RegisteredImportPlugin{
+      RegisteredImportPlugin( std::unique_ptr<ImportPlugin> );
+   };
+
+   // Objects of this type are statically constructed in files, to identify
+   // unsupported import formats; typically in a conditional compilation
+   struct RegisteredUnusableImportPlugin{
+      RegisteredUnusableImportPlugin( std::unique_ptr<UnusableImportPlugin> );
+   };
+
    Importer();
    ~Importer();
 
@@ -148,8 +161,8 @@ private:
    static Importer mInstance;
 
    ExtImportItems mExtImportItems;
-   ImportPluginList mImportPluginList;
-   UnusableImportPluginList mUnusableImportPluginList;
+   static ImportPluginList &sImportPluginList();
+   static UnusableImportPluginList &sUnusableImportPluginList();
 };
 
 //----------------------------------------------------------------------------

src/import/ImportFFmpeg.cpp

@@ -21,7 +21,6 @@ Licensed under the GNU General Public License v2 or later
 *//*******************************************************************/
 
 #include "../Audacity.h"    // needed before FFmpeg.h // for USE_* macros
-#include "ImportFFmpeg.h"
 
 #include "../Experimental.h"
 
@@ -152,6 +151,7 @@ static const auto exts = {
 };
 
 // all the includes live here by default
+#include "Import.h"
 #include "../Tags.h"
 #include "../WaveTrack.h"
 #include "ImportPlugin.h"
@@ -182,6 +182,8 @@ public:
 
    ///! Probes the file and opens it if appropriate
    std::unique_ptr<ImportFileHandle> Open(const FilePath &Filename) override;
+   
+   unsigned SequenceNumber() const override;
 };
 
 ///! Does acual import, returned by FFmpegImportPlugin::Open
@@ -282,13 +284,6 @@ private:
 };
 
 
-void GetFFmpegImportPlugin(ImportPluginList &importPluginList,
-                           UnusableImportPluginList &WXUNUSED(unusableImportPluginList))
-{
-   importPluginList.push_back( std::make_unique<FFmpegImportPlugin>() );
-}
-
-
 wxString FFmpegImportPlugin::GetPluginFormatDescription()
 {
    return DESC;
@@ -336,6 +331,15 @@ std::unique_ptr<ImportFileHandle> FFmpegImportPlugin::Open(const FilePath &filen
    return std::move(handle);
 }
 
+unsigned FFmpegImportPlugin::SequenceNumber() const
+{
+   return 60;
+}
+
+static Importer::RegisteredImportPlugin registered{
+   std::make_unique< FFmpegImportPlugin >()
+};
+
 
 FFmpegImportFileHandle::FFmpegImportFileHandle(const FilePath & name)
 :  ImportFileHandle(name)

src/import/ImportFFmpeg.h

@@ -1,19 +0,0 @@
-/**********************************************************************
-
-Audacity: A Digital Audio Editor
-
-ImportFFmpeg.h
-
-LRN
-
-**********************************************************************/
-
-#ifndef __AUDACITY_IMPORT_FFMPEG__
-#define __AUDACITY_IMPORT_FFMPEG__
-
-#include "ImportForwards.h"
-
-void GetFFmpegImportPlugin(ImportPluginList &importPluginList,
-                           UnusableImportPluginList &unusableImportPluginList);
-
-#endif

src/import/ImportFLAC.cpp

@@ -23,7 +23,6 @@
 *//*******************************************************************/
 
 #include "../Audacity.h" // for USE_* macros
-#include "ImportFLAC.h"
 
 #include "../Experimental.h"
 
@@ -39,6 +38,7 @@
 #include <wx/intl.h>    // needed for _("translated stings") even if we
                         // don't have libflac available
 
+#include "Import.h"
 #include "ImportPlugin.h"
 
 #include "../Tags.h"
@@ -56,14 +56,10 @@ static const auto exts = {
 
 #ifndef USE_LIBFLAC
 
-void GetFLACImportPlugin(ImportPluginList &importPluginList,
-                        UnusableImportPluginList &unusableImportPluginList)
-{
-   unusableImportPluginList.push_back(
+static Importer::RegisteredUnusableImportPlugin registered{
       std::make_unique<UnusableImportPlugin>
          (DESC, FileExtensions( exts.begin(), exts.end() ) )
-   );
-}
+};
 
 #else /* USE_LIBFLAC */
 
@@ -138,6 +134,8 @@ class FLACImportPlugin final : public ImportPlugin
    wxString GetPluginStringID() override { return wxT("libflac"); }
    wxString GetPluginFormatDescription() override;
    std::unique_ptr<ImportFileHandle> Open(const FilePath &Filename)  override;
+
+   unsigned SequenceNumber() const override;
 };
 
 
@@ -285,14 +283,6 @@ FLAC__StreamDecoderWriteStatus MyFLACFile::write_callback(const FLAC__Frame *fra
    }, MakeSimpleGuard(FLAC__STREAM_DECODER_WRITE_STATUS_ABORT) );
 }
 
-
-void GetFLACImportPlugin(ImportPluginList &importPluginList,
-                         UnusableImportPluginList &WXUNUSED(unusableImportPluginList))
-{
-   importPluginList.push_back( std::make_unique<FLACImportPlugin>() );
-}
-
-
 wxString FLACImportPlugin::GetPluginFormatDescription()
 {
     return DESC;
@@ -340,6 +330,14 @@ std::unique_ptr<ImportFileHandle> FLACImportPlugin::Open(const FilePath &filenam
    return std::move(handle);
 }
 
+unsigned FLACImportPlugin::SequenceNumber() const
+{
+   return 30;
+}
+
+static Importer::RegisteredImportPlugin registered{
+   std::make_unique< FLACImportPlugin >()
+};
 
 FLACImportFileHandle::FLACImportFileHandle(const FilePath & name)
 :  ImportFileHandle(name),

src/import/ImportFLAC.h

@@ -1,20 +0,0 @@
-/**********************************************************************
-
-  Audacity: A Digital Audio Editor
-
-  ImportFLAC.h
-
-  Sami Liedes
-
-**********************************************************************/
-
-#ifndef __AUDACITY_IMPORT_FLAC__
-#define __AUDACITY_IMPORT_FLAC__
-
-#include "ImportForwards.h"
-
-void GetFLACImportPlugin(ImportPluginList &importPluginList,
-                         UnusableImportPluginList &unusableImportPluginList);
-
-
-#endif

src/import/ImportGStreamer.cpp

@@ -248,6 +248,8 @@ public:
 
    ///! Probes the file and opens it if appropriate
    std::unique_ptr<ImportFileHandle> Open(const wxString &Filename) override;
+
+   unsigned SequenceNumber() const override;
 };
 
 // ============================================================================
@@ -256,10 +258,9 @@ public:
 
 // ----------------------------------------------------------------------------
 // Instantiate GStreamerImportPlugin and add to the list of known importers
-void
-GetGStreamerImportPlugin(ImportPluginList &importPluginList,
-                         UnusableImportPluginList & WXUNUSED(unusableImportPluginList))
-{
+
+static
+Importer::RegisteredImportPlugin{ []() -> std::unique_ptr< ImportPlugin > {
    wxLogMessage(_TS("Audacity is built against GStreamer version %d.%d.%d-%d"),
                 GST_VERSION_MAJOR,
                 GST_VERSION_MINOR,
@@ -281,7 +282,7 @@ GetGStreamerImportPlugin(ImportPluginList &importPluginList,
       wxLogMessage(wxT("Failed to initialize GStreamer. Error %d: %s"),
                    error.get()->code,
                    wxString::FromUTF8(error.get()->message));
-      return;
+      return {};
    }
 
    guint major, minor, micro, nano;
@@ -297,11 +298,11 @@ GetGStreamerImportPlugin(ImportPluginList &importPluginList,
 
    // No supported extensions...no gstreamer plugins installed
    if (plug->GetSupportedExtensions().size() == 0)
-      return;
+      return {};
 
    // Add to list of importers
-   importPluginList.push_back( std::move(plug) );
-}
+   return std::move(plug);
+}() } registered;
 
 // ============================================================================
 // GStreamerImportPlugin Class
@@ -1145,6 +1146,11 @@ GStreamerImportFileHandle::Import(TrackFactory *trackFactory,
    return updateResult;
 }
 
+unsigned GStreamerImportPlugin::SequenceNumber() const
+{
+   return 80;
+}
+
 // ----------------------------------------------------------------------------
 // Message handlers
 // ----------------------------------------------------------------------------

src/import/ImportGStreamer.h

@@ -1,19 +0,0 @@
-/**********************************************************************
-
-Audacity: A Digital Audio Editor
-
-ImportGStreamer.h
-
-LRN
-
-**********************************************************************/
-
-#ifndef __AUDACITY_IMPORT_GSTREAMER__
-#define __AUDACITY_IMPORT_GSTREAMER__
-
-#include "ImportPlugin.h"
-
-void GetGStreamerImportPlugin(ImportPluginList &importPluginList,
-                           UnusableImportPluginList &unusableImportPluginList);
-
-#endif

src/import/ImportLOF.cpp

@@ -70,7 +70,6 @@
 *//*******************************************************************/
 
 #include "../Audacity.h" // for USE_* macros
-#include "ImportLOF.h"
 
 #include <wx/string.h>
 #include <wx/utils.h>
@@ -84,6 +83,7 @@
 #include "../FileNames.h"
 #include "../WaveTrack.h"
 #include "ImportPlugin.h"
+#include "Import.h"
 #include "../Menus.h"
 #include "../NoteTrack.h"
 #include "../Project.h"
@@ -116,6 +116,8 @@ public:
    wxString GetPluginStringID() override { return wxT("lof"); }
    wxString GetPluginFormatDescription() override;
    std::unique_ptr<ImportFileHandle> Open(const FilePath &Filename) override;
+
+   unsigned SequenceNumber() const override;
 };
 
 
@@ -171,12 +173,6 @@ LOFImportFileHandle::LOFImportFileHandle
 {
 }
 
-void GetLOFImportPlugin(ImportPluginList &importPluginList,
-                        UnusableImportPluginList & WXUNUSED(unusableImportPluginList))
-{
-   importPluginList.push_back( std::make_unique<LOFImportPlugin>() );
-}
-
 wxString LOFImportPlugin::GetPluginFormatDescription()
 {
     return DESC;
@@ -272,6 +268,15 @@ ProgressResult LOFImportFileHandle::Import(
    return ProgressResult::Success;
 }
 
+unsigned LOFImportPlugin::SequenceNumber() const
+{
+   return 50;
+}
+
+static Importer::RegisteredImportPlugin registered{
+   std::make_unique< LOFImportPlugin >()
+};
+
 /** @brief Processes a single line from a LOF text file, doing whatever is
  * indicated on the line.
  *

src/import/ImportLOF.h

@@ -1,62 +0,0 @@
-/**********************************************************************
-
-  Audacity: A Digital Audio Editor
-
-  ImportLOF.h
-
-  David I. Murray
-
-  Supports the opening of ".lof" files which are text files that contain
-  a list of individual files to open in audacity in specific formats.
-
-  (In BNF) The syntax for an LOF file, denoted by <lof>:
-
-  <lof> ::= [<window> | <file> | <#>]*
-  <window> ::= window [<window-parameter>]* <newline>
-  <window-parameter> ::= offset <time> | duration <time>
-  <time> ::= [<digit>]+ [ . [<digit>]* ]
-  <file> ::= file [<file-parameter>]* <newline>
-  <file-parameter> ::= offset <time>
-  <#> ::= <comment> <newline>
-
-  EXAMPLE LOF file:
-
-  # everything following the hash character is ignored
-  window # an initial window command is implicit and optional
-  file "C:\folder1\sample1.wav"    # sample1.wav is displayed
-  file "C:\sample2.wav" offset 5   # sample2 is displayed with a 5s offset
-  File "C:\sample3.wav"            # sample3 is displayed with no offset
-  window offset 5 duration 10      # open a NEW window, zoom to display
-  # 10 seconds total starting at 5 (ending at 15) seconds
-  file "C:\sample3.wav" offset 2.5
-
-  SEMANTICS:
-
-  There are two commands: "window" creates a NEW window, and "file"
-  appends a track to the current window and displays the file there. The
-  first file is always placed in a NEW window, whether or not an initial
-  "window" command is given.
-
-  Commands have optional keyword parameters that may be listed in any
-  order. A parameter should only occur once per command. The "offset"
-  parameter specifies a time offset. For windows, this is the leftmost
-  time displayed in the window. For files, the offset is an amount by
-  which the file is shifted in time before display (only enabled for audio;
-  not midi). The offset is specified as an integer or decimal number of
-  seconds, and the default value is zero.
-
-  Windows may also have a "duration" parameter, which specifies how much
-  time should be displayed in the window. The default duration is equal
-  to the duration of the longest track currently displayed.
-
-**********************************************************************/
-
-#ifndef __AUDACITY_IMPORT_LOF__
-#define __AUDACITY_IMPORT_LOF__
-
-#include "ImportForwards.h"
-
-void GetLOFImportPlugin(ImportPluginList &importPluginList,
-                        UnusableImportPluginList &unusableImportPluginList);
-
-#endif

src/import/ImportMP3.cpp

@@ -27,7 +27,6 @@
 *//*******************************************************************/
 
 #include "../Audacity.h" // for USE_* macros
-#include "ImportMP3.h"
 
 // For compilers that support precompilation, includes "wx/wx.h".
 #include <wx/wxprec.h>
@@ -40,6 +39,7 @@
 #include <wx/intl.h>
 
 #include "../Prefs.h"
+#include "Import.h"
 #include "ImportPlugin.h"
 #include "../Tags.h"
 #include "../prefs/QualityPrefs.h"
@@ -55,14 +55,10 @@ static const auto exts = {
 
 #ifndef USE_LIBMAD
 
-void GetMP3ImportPlugin(ImportPluginList &importPluginList,
-                        UnusableImportPluginList &unusableImportPluginList)
-{
-   unusableImportPluginList.push_back(
+static Importer::RegisteredUnusableImportPlugin registered{
       std::make_unique<UnusableImportPlugin>
          (DESC, FileExtensions( exts.begin(), exts.end() ) )
-  );
-}
+};
 
 #else /* USE_LIBMAD */
 
@@ -120,6 +116,8 @@ public:
    wxString GetPluginStringID() override { return wxT("libmad"); }
    wxString GetPluginFormatDescription() override;
    std::unique_ptr<ImportFileHandle> Open(const FilePath &Filename) override;
+
+   unsigned SequenceNumber() const override;
 };
 
 class MP3ImportFileHandle final : public ImportFileHandle
@@ -157,12 +155,6 @@ private:
    mad_decoder mDecoder;
 };
 
-void GetMP3ImportPlugin(ImportPluginList &importPluginList,
-                        UnusableImportPluginList & WXUNUSED(unusableImportPluginList))
-{
-   importPluginList.push_back( std::make_unique<MP3ImportPlugin>() );
-}
-
 /* The MAD callbacks */
 enum mad_flow input_cb(void *_data, struct mad_stream *stream);
 enum mad_flow output_cb(void *_data,
@@ -263,6 +255,15 @@ ProgressResult MP3ImportFileHandle::Import(
    return privateData.updateResult;
 }
 
+unsigned MP3ImportPlugin::SequenceNumber() const
+{
+   return 40;
+}
+
+static Importer::RegisteredImportPlugin registered{
+   std::make_unique< MP3ImportPlugin >()
+};
+
 MP3ImportFileHandle::~MP3ImportFileHandle()
 {
 }

src/import/ImportMP3.h

@@ -1,19 +0,0 @@
-/**********************************************************************
-
-  Audacity: A Digital Audio Editor
-
-  ImportMP3.h
-
-  Dominic Mazzoni
-
-**********************************************************************/
-
-#ifndef __AUDACITY_IMPORT_MP3__
-#define __AUDACITY_IMPORT_MP3__
-
-#include "ImportForwards.h"
-
-void GetMP3ImportPlugin(ImportPluginList &importPluginList,
-                        UnusableImportPluginList &unusableImportPluginList);
-
-#endif

src/import/ImportOGG.cpp

@@ -29,7 +29,6 @@
 *//*******************************************************************/
 
 #include "../Audacity.h" // for USE_* macros
-#include "ImportOGG.h"
 
 // For compilers that support precompilation, includes "wx/wx.h".
 #include <wx/wxprec.h>
@@ -39,6 +38,7 @@
 #endif
 
 #include <wx/intl.h>
+#include "Import.h"
 #include "../Prefs.h"
 #include "../Tags.h"
 #include "../prefs/QualityPrefs.h"
@@ -55,14 +55,10 @@ static const auto exts = {
 /* BPF There is no real reason to compile without LIBVORBIS, but if you do, you will needs this header */
 #include "ImportPlugin.h"
 
-void GetOGGImportPlugin(ImportPluginList &importPluginList,
-                        UnusableImportPluginList &unusableImportPluginList)
-{
-   unusableImportPluginList.push_back(
+static Importer::RegisteredUnusableImportPlugin registered{
       std::make_unique<UnusableImportPlugin>
          (DESC, FileExtensions( exts.begin(), exts.end() ) )
-   );
-}
+};
 
 #else /* USE_LIBVORBIS */
 
@@ -94,6 +90,8 @@ public:
    wxString GetPluginStringID() override { return wxT("liboggvorbis"); }
    wxString GetPluginFormatDescription() override;
    std::unique_ptr<ImportFileHandle> Open(const FilePath &Filename) override;
+
+   unsigned SequenceNumber() const override;
 };
 
 
@@ -159,11 +157,6 @@ private:
    sampleFormat   mFormat;
 };
 
-void GetOGGImportPlugin(ImportPluginList &importPluginList,
-                        UnusableImportPluginList & WXUNUSED(unusableImportPluginList))
-{
-   importPluginList.push_back( std::make_unique<OggImportPlugin>() );
-}
 
 wxString OggImportPlugin::GetPluginFormatDescription()
 {
@@ -216,6 +209,15 @@ std::unique_ptr<ImportFileHandle> OggImportPlugin::Open(const FilePath &filename
    return std::make_unique<OggImportFileHandle>(filename, std::move(file), std::move(vorbisFile));
 }
 
+unsigned OggImportPlugin::SequenceNumber() const
+{
+   return 20;
+}
+
+static Importer::RegisteredImportPlugin registered{
+   std::make_unique< OggImportPlugin >()
+};
+
 wxString OggImportFileHandle::GetFileDescription()
 {
    return DESC;

src/import/ImportOGG.h

@@ -1,19 +0,0 @@
-/**********************************************************************
-
-  Audacity: A Digital Audio Editor
-
-  ImportOGG.h
-
-  Joshua Haberman
-
-**********************************************************************/
-
-#ifndef __AUDACITY_IMPORT_OGG__
-#define __AUDACITY_IMPORT_OGG__
-
-#include "ImportForwards.h"
-
-void GetOGGImportPlugin(ImportPluginList &importPluginList,
-                        UnusableImportPluginList &unusableImportPluginList);
-
-#endif

src/import/ImportPCM.cpp

@@ -20,8 +20,8 @@
 *//*******************************************************************/
 
 #include "../Audacity.h" // for USE_* macros
-#include "ImportPCM.h"
 
+#include "Import.h"
 #include "../Tags.h"
 
 #include <wx/wx.h>
@@ -84,6 +84,8 @@ public:
    wxString GetPluginStringID() override { return wxT("libsndfile"); }
    wxString GetPluginFormatDescription() override;
    std::unique_ptr<ImportFileHandle> Open(const FilePath &Filename) override;
+
+   unsigned SequenceNumber() const override;
 };
 
 
@@ -115,12 +117,6 @@ private:
    sampleFormat          mFormat;
 };
 
-void GetPCMImportPlugin(ImportPluginList & importPluginList,
-                        UnusableImportPluginList & WXUNUSED(unusableImportPluginList))
-{
-   importPluginList.push_back( std::make_unique<PCMImportPlugin>() );
-}
-
 wxString PCMImportPlugin::GetPluginFormatDescription()
 {
     return DESC;
@@ -190,6 +186,15 @@ std::unique_ptr<ImportFileHandle> PCMImportPlugin::Open(const FilePath &filename
    return std::make_unique<PCMImportFileHandle>(filename, std::move(file), info);
 }
 
+unsigned PCMImportPlugin::SequenceNumber() const
+{
+   return 10;
+}
+
+static Importer::RegisteredImportPlugin registered{
+   std::make_unique< PCMImportPlugin >()
+};
+
 PCMImportFileHandle::PCMImportFileHandle(const FilePath &name,
                                          SFFile &&file, SF_INFO info)
 :  ImportFileHandle(name),

src/import/ImportPCM.h

@@ -1,20 +0,0 @@
-/**********************************************************************
-
-  Audacity: A Digital Audio Editor
-
-  ImportPCM.h
-
-  Dominic Mazzoni
-
-**********************************************************************/
-
-#ifndef __AUDACITY_IMPORT_PCM__
-#define __AUDACITY_IMPORT_PCM__
-
-#include "ImportForwards.h"
-
-void GetPCMImportPlugin(ImportPluginList &importPluginList,
-                        UnusableImportPluginList &unusableImportPluginList);
-
-
-#endif

src/import/ImportPlugin.h

@@ -40,16 +40,6 @@ been compiled or are not available in this version of Audacity.  Has
 enough information to identify the file extensions that would be used,
 but little else.
 
-*//****************************************************************//**
-
-\class ImportPluginList
-\brief An ImportPlugin list.
-
-*//****************************************************************//**
-
-\class UnusableImportPluginList
-\brief An UnusableImportPlugin list.
-
 *//*******************************************************************/
 
 #ifndef __AUDACITY_IMPORTER__
@@ -104,6 +94,8 @@ public:
    // state.
    virtual std::unique_ptr<ImportFileHandle> Open(const FilePath &Filename) = 0;
 
+   virtual unsigned SequenceNumber() const = 0;
+
    virtual ~ImportPlugin() { }
 
 protected:

src/import/ImportQT.cpp

@@ -14,8 +14,8 @@
 **********************************************************************/
 
 #include "../Audacity.h" // for USE_* macros
-#include "ImportQT.h"
 
+#include "Import.h"
 #include "ImportPlugin.h"
 #include "../widgets/AudacityMessageBox.h"
 #include "../widgets/ProgressDialog.h"
@@ -38,19 +38,17 @@ static const auto exts = {
 
 #ifndef USE_QUICKTIME
 
-void GetQTImportPlugin(ImportPluginList &importPluginList,
-                       UnusableImportPluginList &unusableImportPluginList)
-{
-// Bug 2068: misleading error message about QuickTime  
+// Bug 2068: misleading error message about QuickTime
 // In 64 bit versions we cannot compile in (obsolete) QuickTime
 // So don't register the QuickTime extensions, so ensuring we never report
 // "This version of Audacity was not compiled with QuickTime files support"  
 // When attempting to import MP4 files.
-//   unusableImportPluginList.push_back(
-//      std::make_unique<UnusableImportPlugin>(DESC,
-//         FileExtensions( exts.begin(), exts.end() ) )
-//   );
-}
+/*
+static Importer::RegisteredUnusableImportPlugin registered{
+      std::make_unique<UnusableImportPlugin>(DESC,
+         FileExtensions( exts.begin(), exts.end() ) )
+};
+*/
 
 #else /* USE_QUICKTIME */
 
@@ -126,6 +124,8 @@ class QTImportPlugin final : public ImportPlugin
    wxString GetPluginFormatDescription();
    std::unique_ptr<ImportFileHandle> Open(const wxString & Filename) override;
 
+   unsigned SequenceNumber() const override;
+
  private:
    bool mInitialized;
 };
@@ -175,12 +175,6 @@ class QTImportFileHandle final : public ImportFileHandle
    Movie mMovie;
 };
 
-void GetQTImportPlugin(ImportPluginList &importPluginList,
-                       UnusableImportPluginList &unusableImportPluginList)
-{
-   importPluginList.push_back( std::make_unique<QTImportPlugin>() );
-}
-
 wxString QTImportPlugin::GetPluginFormatDescription()
 {
    return DESC;
@@ -226,6 +220,15 @@ std::unique_ptr<ImportFileHandle> QTImportPlugin::Open(const wxString & Filename
    return std::make_unique<QTImportFileHandle>(Filename, theMovie);
 }
 
+unsigned QTImportPlugin::SequenceNumber() const
+{
+   return 70;
+}
+
+static Importer::RegisteredImportPlugin registered{
+   std::make_unique< QTImportPlugin >()
+};
+
 
 wxString QTImportFileHandle::GetFileDescription()
 {

src/import/ImportQT.h

@@ -1,19 +0,0 @@
-/**********************************************************************
-
-  Audacity: A Digital Audio Editor
-
-  ImportQT.h
-
-  Joshua Haberman
-
-**********************************************************************/
-
-#ifndef __AUDACITY_IMPORT_QT__
-#define __AUDACITY_IMPORT_QT__
-
-#include "ImportForwards.h"
-
-void GetQTImportPlugin(ImportPluginList &importPluginList,
-                       UnusableImportPluginList &unusableImportPluginList);
-
-#endif