vendor c/common@852ca05a1f

Also force an update of c/image to prevent a downgrade.

Signed-off-by: Valentin Rothberg <vrothberg@redhat.com>

vendor/github.com/containers/common/pkg/config/db_backend.go

@@ -0,0 +1,60 @@
+package config
+
+import "fmt"
+
+// DBBackend determines which supported database backend Podman should use.
+type DBBackend int
+
+const (
+	// Unsupported database backend.  Used as a sane base value for the type.
+	DBBackendUnsupported DBBackend = iota
+	// BoltDB backend.
+	DBBackendBoltDB
+	// SQLite backend.
+	DBBackendSQLite
+
+	stringBoltDB = "boltdb"
+	stringSQLite = "sqlite"
+)
+
+// String returns the DBBackend's string representation.
+func (d DBBackend) String() string {
+	switch d {
+	case DBBackendBoltDB:
+		return stringBoltDB
+	case DBBackendSQLite:
+		return stringSQLite
+	default:
+		return fmt.Sprintf("unsupported database backend: %d", d)
+	}
+}
+
+// Validate returns whether the DBBackend is supported.
+func (d DBBackend) Validate() error {
+	switch d {
+	case DBBackendBoltDB, DBBackendSQLite:
+		return nil
+	default:
+		return fmt.Errorf("unsupported database backend: %d", d)
+	}
+}
+
+// ParseDBBackend parses the specified string into a DBBackend.
+// An error is return for unsupported backends.
+func ParseDBBackend(raw string) (DBBackend, error) {
+	// NOTE: this function should be used for parsing the user-specified
+	// values on Podman's CLI.
+	switch raw {
+	case stringBoltDB:
+		return DBBackendBoltDB, nil
+	case stringSQLite:
+		return DBBackendSQLite, nil
+	default:
+		return DBBackendUnsupported, fmt.Errorf("unsupported database backend: %q", raw)
+	}
+}
+
+// DBBackend returns the configured database backend.
+func (c *Config) DBBackend() (DBBackend, error) {
+	return ParseDBBackend(c.Engine.DBBackend)
+}