Set all anti-cgo options and add comment

db.go

@@ -2,6 +2,7 @@ package headscale
 
 import (
 	"errors"
+	"time"
 
 	"github.com/glebarez/sqlite"
 	"gorm.io/driver/postgres"
@@ -81,13 +82,24 @@ func (h *Headscale) openDB() (*gorm.DB, error) {
 
 	switch h.dbType {
 	case Sqlite:
-		db, err = gorm.Open(sqlite.Open(h.dbString), &gorm.Config{
-			DisableForeignKeyConstraintWhenMigrating: true,
-			Logger:                                   log,
-		})
+		db, err = gorm.Open(
+			sqlite.Open(h.dbString+"?_synchronous=1&_journal_mode=WAL"),
+			&gorm.Config{
+				DisableForeignKeyConstraintWhenMigrating: true,
+				Logger:                                   log,
+			},
+		)
 
+		db.Exec("PRAGMA foreign_keys=ON")
+
+		// The pure Go SQLite library does not handle locking in
+		// the same way as the C based one and we cant use the gorm
+		// connection pool as of 2022/02/23.
 		sqlDB, _ := db.DB()
+		sqlDB.SetMaxIdleConns(1)
 		sqlDB.SetMaxOpenConns(1)
+		sqlDB.SetConnMaxIdleTime(time.Hour)
+
 	case Postgres:
 		db, err = gorm.Open(postgres.Open(h.dbString), &gorm.Config{
 			DisableForeignKeyConstraintWhenMigrating: true,