store: fix split view blinking

When split view and threading mode are enabled, the message is blinking.
First, since commit ddfa5cac1fe9 ("msgstore: fix deadlock in thread
builder"), the threadCallback is never set to nil: the thread builder
calls it continuously.
After setting it to nil, the message is still blinking once. To avoid this,
don't call the onSelect method (which points to
AccountView.updateSplitView()) from the thread builder: the message is
already displayed.

Let's rewrite Select and selectPriv:
 - Select(): it takes the lock and calls the onSelect callback;
 - selectPriv: the assumption is that the lock is held. It doesn't call
   the onSelect callback. This function is only used by the thread builder.

Fixes: 588be1a28422 ("store: improve cursor position")
Fixes: ddfa5cac1fe9 ("msgstore: fix deadlock in thread builder")
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Robin Jarry <robin@jarry.cc>

1 files changed, 14 insertions, 10 deletions

diff --git a/lib/msgstore.go b/lib/msgstore.go
index 33daa9ff..274e42ba 100644
--- a/lib/msgstore.go
+++ b/lib/msgstore.go
@@ -718,22 +718,26 @@ func (store *MessageStore) SelectedUid() uint32 {
 }
 
 func (store *MessageStore) Select(uid uint32) {
-	store.threadsMutex.Lock()
-	if store.threadCallback != nil {
-		store.threadCallback = nil
+	store.selectPriv(uid, false)
+	if store.onSelect != nil {
+		store.onSelect(store.Selected())
 	}
-	store.threadsMutex.Unlock()
-	store.selectPriv(uid)
 }
 
-func (store *MessageStore) selectPriv(uid uint32) {
+func (store *MessageStore) selectPriv(uid uint32, lockHeld bool) {
+	if !lockHeld {
+		store.threadsMutex.Lock()
+	}
+	if store.threadCallback != nil {
+		store.threadCallback = nil
+	}
+	if !lockHeld {
+		store.threadsMutex.Unlock()
+	}
 	store.selectedUid = uid
 	if store.marker != nil {
 		store.marker.UpdateVisualMark()
 	}
-	if store.onSelect != nil {
-		store.onSelect(store.Selected())
-	}
 }
 
 func (store *MessageStore) NextPrev(delta int) {
@@ -761,7 +765,7 @@ func (store *MessageStore) NextPrev(delta int) {
 		store.threadsMutex.Lock()
 		store.threadCallback = func() {
 			if uids := store.Uids(); len(uids) > newIdx {
-				store.selectPriv(uids[newIdx])
+				store.selectPriv(uids[newIdx], true)
 			}
 		}
 		store.threadsMutex.Unlock()