Major update for stability

RsyncManager/Utilities/KeychainStore.swift

@@ -19,23 +19,37 @@ enum KeychainStore {
         return value
     }
 
-    static func set(_ value: String, for account: String) {
+    @discardableResult
+    static func set(_ value: String, for account: String) -> OSStatus {
         let base: [String: Any] = [
             kSecClass as String: kSecClassGenericPassword,
             kSecAttrService as String: service,
             kSecAttrAccount as String: account
         ]
-        if value.isEmpty {
-            SecItemDelete(base as CFDictionary)
-            return
-        }
+        if value.isEmpty { return delete(account) }
+
         let data = Data(value.utf8)
-        let update: [String: Any] = [kSecValueData as String: data]
-        if SecItemUpdate(base as CFDictionary, update as CFDictionary) == errSecItemNotFound {
-            var add = base
-            add[kSecValueData as String] = data
-            add[kSecAttrAccessible as String] = kSecAttrAccessibleAfterFirstUnlock
-            SecItemAdd(add as CFDictionary, nil)
-        }
+        let update: [String: Any] = [
+            kSecValueData as String: data,
+            kSecAttrAccessible as String: kSecAttrAccessibleWhenUnlocked
+        ]
+        let updateStatus = SecItemUpdate(base as CFDictionary, update as CFDictionary)
+        if updateStatus != errSecItemNotFound { return updateStatus }
+
+        var add = base
+        add[kSecValueData as String] = data
+        add[kSecAttrAccessible as String] = kSecAttrAccessibleWhenUnlocked
+        return SecItemAdd(add as CFDictionary, nil)
+    }
+
+    @discardableResult
+    static func delete(_ account: String) -> OSStatus {
+        let query: [String: Any] = [
+            kSecClass as String: kSecClassGenericPassword,
+            kSecAttrService as String: service,
+            kSecAttrAccount as String: account
+        ]
+        let status = SecItemDelete(query as CFDictionary)
+        return status == errSecItemNotFound ? errSecSuccess : status
     }
 }