mini: fix silent failure on meta-key insertion

fixes ElektraInitiative#4582

Author: Bujuhu

doc/news/_preparation_next_release.md

@@ -160,6 +160,12 @@ The following text lists news about the [plugins](https://www.libelektra.org/plu
 - Add encoding test for blockresolver read _(@dtdirect)_
 - Refactor and restructure blockresolver _(@dtdirect)_
 
+### mini
+
+- Fix a bug where writing meta keys will fail silently _(Juri Schreib @Bujuhu)_
+- <<TODO>>
+- <<TODO>>
+
 ### mmapstorage
 
 - Remove code duplication in the data block calculation _(Richard Stöckl @Eiskasten)_

src/plugins/mini/mini.c

@@ -317,9 +317,37 @@ int elektraMiniGet (Plugin * handle ELEKTRA_UNUSED, KeySet * returned, Key * par
 	return parseFile (returned, parentKey);
 }
 
+
+static bool elektraCheckForInvalidMetaKey (Key * parentKey, KeySet * ks)
+{
+	Key * cur = 0;
+	for (elektraCursor it = 0; it < ksGetSize (ks); ++it)
+	{
+		cur = ksAtCursor (ks, it);
+		const KeySet * metaKeys = keyMeta (cur);
+		for (elektraCursor jt = 0; jt < ksGetSize (metaKeys); ++jt)
+		{
+			// We reach her iff we try to set a metakey. Therefore we should t
+			const Key * meta = ksAtCursor (metaKeys, jt);
+			const char * pos = (const char *) keyName (meta);
+			if (elektraStrNCmp (pos, "meta:/internal/mini", 19) != 0 && elektraStrCmp (pos, "meta:/origname") && elektraStrNCmp (pos, "meta:/rename", 12) != 0 && elektraStrCmp (pos, "meta:/binary") != 0)
+			{
+				ELEKTRA_SET_RESOURCE_ERRORF (parentKey, "The mini storage Plugin doesn't support the met key %s", pos);
+				return false;
+			}
+		}
+	}
+	return true;
+}
+
 /** @see elektraDocSet */
 int elektraMiniSet (Plugin * handle ELEKTRA_UNUSED, KeySet * returned, Key * parentKey)
 {
+	if (!elektraCheckForInvalidMetaKey (parentKey, returned))
+	{
+		return ELEKTRA_PLUGIN_STATUS_ERROR;
+	}
+
 	ELEKTRA_LOG ("Write configuration data");
 	int errorNumber = errno;
 	FILE * destination = fopen (keyString (parentKey), "w");

src/plugins/mini/testmod_mini.c

@@ -113,6 +113,21 @@ static void test_set (void)
 	PLUGIN_CLOSE ();
 }
 
+static void test_setMetaMustFail (void)
+{
+	char const * const prefix = "user:/mini/tests/writeMeta";
+
+	Key * parentKey = keyNew (prefix, KEY_VALUE, elektraFilename (), KEY_END);
+	KeySet * conf = ksNew (0, KS_END);
+	KeySet * ks = ksNew (1, keyNew ("user:/mini/tests/writeMeta", KEY_VALUE, "asdf", KEY_META, "asdf", "asdf", KEY_END), KS_END);
+
+	PLUGIN_OPEN ("mini");
+	succeed_if (plugin->kdbSet (plugin, ks, parentKey) == ELEKTRA_PLUGIN_STATUS_ERROR, "Attempting to write a Meta Key did not fail");
+	keyDel (parentKey);
+	ksDel (ks);
+	PLUGIN_CLOSE ();
+}
+
 /* -- Main ------------------------------------------------------------------------------------------------------------------------------ */
 
 int main (int argc, char ** argv)
@@ -125,6 +140,7 @@ int main (int argc, char ** argv)
 	test_basics ();
 	test_get ();
 	test_set ();
+	test_setMetaMustFail ();
 
 	print_result ("testmod_mini");