Fix memory leak with OCI_RETURN_LOBS fetch flag (#32)

Co-authored-by: SakiTakamachi <saki@sakiot.com>

Author: mvorisek

oci8.c

@@ -573,12 +573,8 @@ void php_oci_column_hash_dtor(zval *data)
 		zend_list_close(column->stmtid);
 	}
 
-	if (column->descid) {
-		if (GC_REFCOUNT(column->descid) == 1)
-			zend_list_close(column->descid);
-		else {
-			GC_DELREF(column->descid);
-		}
+	if (column->descid && !GC_DELREF(column->descid)) {
+		zend_list_free(column->descid);
 	}
 
 	if (column->data) {

tests/gh-4-return-lob.phpt

@@ -0,0 +1,43 @@
+--TEST--
+Bug GH-4 (Memory leak with long query/CLOB) with OCI_RETURN_LOBS
+--EXTENSIONS--
+oci8
+--SKIPIF--
+<?php
+require_once 'skipifconnectfailure.inc';
+?>
+--FILE--
+<?php
+
+require __DIR__.'/connect.inc';
+
+$expectedStr = str_repeat('a', 1_001);
+$sql = 'select concat(TO_CLOB(\'' . str_repeat('a', 1_000) . '\'), TO_CLOB(\'a\')) AS "v" from "DUAL"';
+
+$memUsages = array_flip(range(0, 100 - 1));
+foreach (array_keys($memUsages) as $k) {
+    $stid = oci_parse($c, $sql);
+    oci_execute($stid);
+    $row = oci_fetch_array($stid, \OCI_ASSOC | \OCI_RETURN_LOBS);
+    $res = $row['v'];
+    if ($res !== $expectedStr) {
+        var_dump([$expectedStr, $res]);
+        throw new \Exception('unexpected result');
+    }
+
+    $memUsages[$k] = memory_get_usage();
+}
+
+$memUsages = array_slice($memUsages, 1, null, true);
+$memUsages = array_unique($memUsages);
+
+if (count($memUsages) !== 1) {
+    var_dump($memUsages);
+    throw new \Exception('memory leak detected');
+}
+
+echo "ok\n";
+
+?>
+--EXPECTF--
+ok