Fix the reading of autosave files... (#610)

* Fix the reading of autosave files...

... problem was in recreating strings from buffers, but copying too many because
null terminators were lacking.

* Autosave during recording backs up all tracks correctly...

... whether to new track, or appending; and it doesn't lose the other tracks
besides the recording.

It is also unnecessary when just starting to record, so remove one call.

src/ProjectAudioManager.cpp

@@ -854,10 +854,8 @@ void ProjectAudioManager::OnAudioIORate(int rate)
 
 void ProjectAudioManager::OnAudioIOStartRecording()
 {
-   auto &projectFileIO = ProjectFileIO::Get( mProject );
-   // Before recording is started, auto-save the file. The file will have
-   // empty tracks at the bottom where the recording will be put into
-   projectFileIO.AutoSave();
+   // Auto-save was done here before, but it is unnecessary, provided there
+   // are sufficient autosaves when pushing or modifying undo states.
 }
 
 // This is called after recording has stopped and all tracks have flushed.
@@ -931,7 +929,7 @@ void ProjectAudioManager::OnAudioIONewBlockFiles(const WaveTrackArray *tracks)
 {
    auto &project = mProject;
    auto &projectFileIO = ProjectFileIO::Get( project );
-   projectFileIO.AutoSave(tracks);
+   projectFileIO.AutoSave(true);
 }
 
 void ProjectAudioManager::OnCommitRecording()

src/ProjectFileIO.cpp

@@ -1059,7 +1059,7 @@ void ProjectFileIO::WriteXMLHeader(XMLWriter &xmlFile) const
    xmlFile.Write(wxT(">\n"));
 }
 
-void ProjectFileIO::WriteXML(XMLWriter &xmlFile, const WaveTrackArray *tracks)
+void ProjectFileIO::WriteXML(XMLWriter &xmlFile, bool recording)
 // may throw
 {
    auto pProject = mpProject.lock();
@@ -1092,31 +1092,36 @@ void ProjectFileIO::WriteXML(XMLWriter &xmlFile, const WaveTrackArray *tracks)
    tags.WriteXML(xmlFile);
 
    unsigned int ndx = 0;
-   if (tracks)
+   tracklist.Any().Visit([&](Track *t)
    {
-      for (auto track : *tracks)
-      {
-         track->WriteXML(xmlFile);
+      auto useTrack = t;
+      if ( recording ) {
+         // When append-recording, there is a temporary "shadow" track accumulating
+         // changes and displayed on the screen but it is not yet part of the
+         // regular track list.  That is the one that we want to back up.
+         // SubstitutePendingChangedTrack() fetches the shadow, if the track has
+         // one, else it gives the same track back.
+         useTrack = t->SubstitutePendingChangedTrack().get();
       }
-   }
-   else
-   {
-      tracklist.Any().Visit([&](Track *t)
-      {
-         t->WriteXML(xmlFile);
-      });
-   }
+      else if ( useTrack->GetId() == TrackId{} ) {
+         // This is a track added during a non-appending recording that is
+         // not yet in the undo history.  The UndoManager skips backing it up
+         // when pushing.  Don't auto-save it.
+         return;
+      }
+      useTrack->WriteXML(xmlFile);
+   });
 
    xmlFile.EndTag(wxT("project"));
 
    //TIMER_STOP( xml_writer_timer );
 }
 
-bool ProjectFileIO::AutoSave(const WaveTrackArray *tracks)
+bool ProjectFileIO::AutoSave(bool recording)
 {
    ProjectSerializer autosave;
    WriteXMLHeader(autosave);
-   WriteXML(autosave, tracks);
+   WriteXML(autosave, recording);
 
    if (WriteDoc("autosave", autosave))
    {

src/ProjectFileIO.h

@@ -72,7 +72,7 @@ public:
 
    void Reset();
 
-   bool AutoSave(const WaveTrackArray *tracks = nullptr);
+   bool AutoSave(bool recording = false);
    bool AutoSaveDelete(sqlite3 *db = nullptr);
 
    bool LoadProject(const FilePath &fileName);
@@ -81,7 +81,7 @@ public:
 
    XMLTagHandler *HandleXMLChild(const wxChar *tag) override;
    void WriteXMLHeader(XMLWriter &xmlFile) const;
-   void WriteXML(XMLWriter &xmlFile, const WaveTrackArray *tracks = nullptr) /* not override */;
+   void WriteXML(XMLWriter &xmlFile, bool recording = false) /* not override */;
 
    wxLongLong GetFreeDiskSpace();
 

src/ProjectSerializer.cpp

@@ -291,22 +291,27 @@ wxString ProjectSerializer::Decode(const wxMemoryBuffer &buffer, BlockIDs &block
       return iter->second;
    };
 
-   auto Convert = [&mCharSize](char *in, int len) -> wxString
+   auto ReadString = [&mCharSize, &in, &bytes](int len) -> wxString
    {
+      bytes.reserve( len + 4 );
+      auto data = bytes.data();
+      in.Read( data, len );
+      // Make a null terminator of the widest type
+      memset( data + len, '\0', 4 );
       wxUString str;
-
+      
       switch (mCharSize)
       {
          case 1:
-            str.assignFromUTF8(in, len);
+            str.assignFromUTF8(data, len);
          break;
 
          case 2:
-            str.assignFromUTF16((wxChar16 *) in, len / 2);
+            str.assignFromUTF16((wxChar16 *) data, len / 2);
          break;
 
          case 4:
-            str = wxU32CharBuffer::CreateNonOwned((wxChar32 *) in, len / 4);
+            str = wxU32CharBuffer::CreateNonOwned((wxChar32 *) data, len / 4);
          break;
 
          default:
@@ -345,10 +350,7 @@ wxString ProjectSerializer::Decode(const wxMemoryBuffer &buffer, BlockIDs &block
 
                in.Read(&id, sizeof(id));
                in.Read(&len, sizeof(len));
-               bytes.reserve(len);
-               in.Read(bytes.data(), len);
-
-               mIds[id] = Convert(bytes.data(), len);
+               mIds[id] = ReadString(len);
             }
             break;
 
@@ -374,10 +376,7 @@ wxString ProjectSerializer::Decode(const wxMemoryBuffer &buffer, BlockIDs &block
 
                in.Read(&id, sizeof(id));
                in.Read(&len, sizeof(len));
-               bytes.reserve(len);
-               in.Read(bytes.data(), len);
-
-               out.WriteAttr(Lookup(id), Convert(bytes.data(), len));
+               out.WriteAttr(Lookup(id), ReadString(len));
             }
             break;
 
@@ -476,10 +475,7 @@ wxString ProjectSerializer::Decode(const wxMemoryBuffer &buffer, BlockIDs &block
                int len;
 
                in.Read(&len, sizeof(len));
-               bytes.reserve(len);
-               in.Read(bytes.data(), len);
-
-               out.WriteData(Convert(bytes.data(), len));
+               out.WriteData(ReadString(len));
             }
             break;
 
@@ -488,10 +484,7 @@ wxString ProjectSerializer::Decode(const wxMemoryBuffer &buffer, BlockIDs &block
                int len;
 
                in.Read(&len, sizeof(len));
-               bytes.reserve(len);
-               in.Read(bytes.data(), len);
-
-               out.Write(Convert(bytes.data(), len));
+               out.Write(ReadString(len));
             }
             break;