From 69b044e3215335b1b88576e946e7c07a38a7bbe1 Mon Sep 17 00:00:00 2001
From: Leland Lucius <github@homerow.net>
Date: Fri, 17 Apr 2015 16:31:01 -0500
Subject: [PATCH] Restore tracks if recording fails to start

During an append record, silence may need to be added to the
end of the existing track(s) to fill any gap between the end
and the common recording start time.

But, if the recording fails to start, this silence is left at
the ends of the tracks.

This change fixes that by making a copy of the tracks before
recording starts and restoring the tracks from that copy if
the start fails.
---
 src/toolbars/ControlToolBar.cpp | 34 +++++++++++++++++++++++++++++++--
 1 file changed, 32 insertions(+), 2 deletions(-)

diff --git a/src/toolbars/ControlToolBar.cpp b/src/toolbars/ControlToolBar.cpp
index 55a0b2621..af9f27d77 100644
--- a/src/toolbars/ControlToolBar.cpp
+++ b/src/toolbars/ControlToolBar.cpp
@@ -819,6 +819,7 @@ void ControlToolBar::OnRecord(wxCommandEvent &evt)
 
       // If SHIFT key was down, the user wants append to tracks
       int recordingChannels = 0;
+      TrackList *tracksCopy = NULL;
       bool shifted = mRecord->WasShiftDown();
       if (shifted) {
          bool sel = false;
@@ -858,6 +859,16 @@ void ControlToolBar::OnRecord(wxCommandEvent &evt)
                   playbackTracks.Remove(wt);
                t1 = wt->GetEndTime();
                if (t1 < t0) {
+                  if (!tracksCopy) {
+                     tracksCopy = new TrackList();
+                     TrackListIterator iter(t);
+                     Track *trk = iter.First();
+                     while (trk) {
+                        tracksCopy->Add(trk->Duplicate());
+                        trk = iter.Next();
+                     }
+                  }
+
                   WaveTrack *newTrack = p->GetTrackFactory()->NewWaveTrack();
                   newTrack->InsertSilence(0.0, t0 - t1);
                   newTrack->Flush();
@@ -923,10 +934,29 @@ void ControlToolBar::OnRecord(wxCommandEvent &evt)
       if (success) {
          p->SetAudioIOToken(token);
          mBusyProject = p;
+         if (shifted && tracksCopy) {
+            tracksCopy->Clear(true);
+            delete tracksCopy;
+         }
       }
       else {
-         // msmeyer: Delete recently added tracks if opening stream fails
-         if (!shifted) {
+         if (shifted) {
+            // Restore the tracks to remove any inserted silence
+            if (tracksCopy) {
+               t->Clear(true);
+               TrackListIterator iter(tracksCopy);
+               Track *trk = iter.First();
+               while (trk)
+               {
+                  Track *tmp = trk;
+                  trk = iter.RemoveCurrent();
+                  t->Add(tmp);
+               }
+               delete tracksCopy;
+            }
+         }
+         else {
+            // msmeyer: Delete recently added tracks if opening stream fails
             for (unsigned int i = 0; i < newRecordingTracks.GetCount(); i++) {
                t->Remove(newRecordingTracks[i]);
                delete newRecordingTracks[i];