lib/msgstore: protect with a mutex

MessageStore has a lot of exported fields that can be read from the outside.
Each read must be protected, because a call from Update could happen at any
time.

1 files changed, 18 insertions, 0 deletions

diff --git a/widgets/msglist.go b/widgets/msglist.go
index 4f853f3..eeadec7 100644
--- a/widgets/msglist.go
+++ b/widgets/msglist.go
@@ -53,6 +53,8 @@ func (ml *MessageList) Draw(ctx *ui.Context) {
 		return
 	}
 
+	store.Lock()
+
 	var (
 		needsHeaders []uint32
 		row          int = 0
@@ -92,6 +94,8 @@ func (ml *MessageList) Draw(ctx *ui.Context) {
 			tcell.StyleDefault, "%s", msg)
 	}
 
+	store.Unlock()
+
 	if len(needsHeaders) != 0 {
 		store.FetchHeaders(needsHeaders, nil)
 		ml.spinner.Start()
@@ -109,11 +113,13 @@ func (ml *MessageList) storeUpdate(store *lib.MessageStore) {
 		return
 	}
 
+	store.Lock()
 	if len(store.Uids) > 0 {
 		for ml.selected >= len(store.Uids) {
 			ml.Prev()
 		}
 	}
+	store.Unlock()
 
 	ml.Invalidate()
 }
@@ -139,16 +145,25 @@ func (ml *MessageList) Store() *lib.MessageStore {
 
 func (ml *MessageList) Empty() bool {
 	store := ml.Store()
+	store.Lock()
+	defer store.Unlock()
+
 	return store == nil || len(store.Uids) == 0
 }
 
 func (ml *MessageList) Selected() *types.MessageInfo {
 	store := ml.Store()
+	store.Lock()
+	defer store.Unlock()
+
 	return store.Messages[store.Uids[len(store.Uids)-ml.selected-1]]
 }
 
 func (ml *MessageList) Select(index int) {
 	store := ml.Store()
+	store.Lock()
+	defer store.Unlock()
+
 	ml.selected = index
 	for ; ml.selected < 0; ml.selected = len(store.Uids) + ml.selected {
 	}
@@ -166,6 +181,9 @@ func (ml *MessageList) Select(index int) {
 
 func (ml *MessageList) nextPrev(delta int) {
 	store := ml.Store()
+	store.Lock()
+	defer store.Unlock()
+
 	if store == nil || len(store.Uids) == 0 {
 		return
 	}