Check and set multithread on first instance

Author: softlion

src/SQLite.Net/Interop/ConfigOption.cs

@@ -25,6 +25,7 @@ namespace SQLite.Net2
 {
     public enum ConfigOption
     {
+        Unknown = 0,
         SingleThread = 1,
         MultiThread = 2,
         Serialized = 3

src/SQLite.Net/Interop/SQLiteApi.cs

@@ -50,20 +50,17 @@ public Result Close(IDbHandle db)
 
         public Result Initialize()
         {
-            throw new NotImplementedException("");
-            //return (Result)raw.sqlite3_initialize();
+            return (Result)raw.sqlite3_initialize();
         }
 
         public Result Shutdown()
         {
-            throw new NotImplementedException("");
-            //return (Result)raw.sqlite3_shutdown();
+            return (Result)raw.sqlite3_shutdown();
         }
 
         public Result Config(ConfigOption option)
         {
-            throw new NotImplementedException("");
-            //return (Result)raw.sqlite3_config(option);
+            return (Result)raw.sqlite3_config((int)option);
         }
 
         public Result BusyTimeout(IDbHandle db, int milliseconds)
@@ -277,11 +274,11 @@ public int BackupPagecount(IDbBackupHandle handle)
             return raw.sqlite3_backup_pagecount(internalBackup.DbBackupPtr);
         }
 
-        public int Sleep(int millis)
-        {
-            throw new NotImplementedException("Sleep is not implemented");
-            //return raw.sqlite3_sleep(millis);
-        }
+        // public int Sleep(int millis)
+        // {
+        //     throw new NotImplementedException("Sleep is not implemented");
+        //     //return raw.sqlite3_sleep(millis);
+        // }
 
         private struct DbBackupHandle : IDbBackupHandle
         {
@@ -292,10 +289,8 @@ public DbBackupHandle(sqlite3_backup dbBackupPtr) : this()
                 DbBackupPtr = dbBackupPtr;
             }
 
-            public bool Equals(IDbBackupHandle other)
-            {
-                return other is DbBackupHandle && DbBackupPtr == ((DbBackupHandle)other).DbBackupPtr;
-            }
+            public bool Equals(IDbBackupHandle other) 
+                => other is DbBackupHandle handle && DbBackupPtr == handle.DbBackupPtr;
         }
 
         #endregion

src/SQLite.Net/SQLiteConnection.cs

@@ -91,6 +91,8 @@ static SQLiteConnection()
         public virtual SQLiteConnection Clone() 
             => new (DatabasePath, databaseOpenFlags, StoreDateTimeAsTicks, Serializer, _tableMappings, ExtraTypeMappings, Resolver, encryptionKey);
 
+        private static ConfigOption firstConfigOption;
+        
         /// <summary>
         /// Constructs a new SQLiteConnection and opens a SQLite database specified by databasePath.
         /// </summary>
@@ -110,13 +112,25 @@ public virtual SQLiteConnection Clone()
         /// <param name="extraTypeMappings">Any extra type mappings that you wish to use for overriding the default for creating column definitions for SQLite DDL in the class Orm (snake in Swedish).</param>
         /// <param name="resolver">A contract resovler for resolving interfaces to concreate types during object creation</param>
         /// <param name="encryptionKey">When using SQL CIPHER, automatically sets the key (you won't need to override Clone() in this case)</param>
+        /// <param name="configOption">Mode in which to open the db</param>
         public SQLiteConnection(string databasePath, SQLiteOpenFlags openFlags = SQLiteOpenFlags.ReadWrite | SQLiteOpenFlags.Create, bool storeDateTimeAsTicks = true,  IBlobSerializer? serializer = null,  IDictionary<string, TableMapping>? tableMappings = null,
-             IDictionary<Type, string>? extraTypeMappings = null, IContractResolver? resolver = null, string? encryptionKey = null)
+             IDictionary<Type, string>? extraTypeMappings = null, IContractResolver? resolver = null, string? encryptionKey = null, ConfigOption configOption = ConfigOption.MultiThread)
         {
             if (string.IsNullOrEmpty(databasePath))
                 throw new ArgumentException("Must be specified", nameof(databasePath));
             DatabasePath = databasePath;
 
+            if (firstConfigOption == ConfigOption.Unknown)
+            {
+                firstConfigOption = configOption;
+
+                if (configOption > ConfigOption.SingleThread && sqlite.Threadsafe() == 0)
+                    throw new ArgumentException("SQlite is not compiled with multithread and config option is set to multithread", nameof(configOption));
+                
+                sqlite.Config(configOption);
+                sqlite.Initialize();
+            }
+            
             var r = sqlite.Open(DatabasePath, out var handle, (int) openFlags, null);
             if (r != Result.OK)
                 throw new SQLiteException(r, $"Could not open database file: {DatabasePath} ({r})");