Some improvements

plugins/Pass/error.h

@@ -0,0 +1,30 @@
+// error.h
+#ifndef ERROR_H
+#define ERROR_H
+
+extern "C" {
+#include "rnp/rnp_err.h"
+}
+
+enum ErrorCodeShow {
+    UnexceptedError= 1,
+    BadPassphrase,
+    NoKeyFound,
+    DecryptFailed
+};
+
+ErrorCodeShow rnpErrorToErrorCodeShow(int rnpErrorCode) {
+    switch (rnpErrorCode) {
+    case RNP_ERROR_BAD_PASSWORD:
+        return BadPassphrase;
+    case RNP_ERROR_KEY_NOT_FOUND:
+    case RNP_ERROR_NO_SUITABLE_KEY:
+        return NoKeyFound;
+    case RNP_ERROR_DECRYPT_FAILED:
+        return DecryptFailed;
+    default:
+        return UnexceptedError;
+    }
+}
+
+#endif // ERROR_H