From a763a24e13a35fc2f1def08d93a60eebcf0ba290 Mon Sep 17 00:00:00 2001
From: Even Rouault <even.rouault@spatialys.com>
Date: Sun, 15 Sep 2024 22:57:33 +0200
Subject: [PATCH] GML: honour IsSingleAllowedDriver()

---
 autotest/ogr/ogr_gml.py              | 15 +++++++++++++++
 ogr/ogrsf_frmts/gml/ogrgmldriver.cpp |  3 +++
 2 files changed, 18 insertions(+)

diff --git a/autotest/ogr/ogr_gml.py b/autotest/ogr/ogr_gml.py
index d4624b100a7b..ed21fe892650 100755
--- a/autotest/ogr/ogr_gml.py
+++ b/autotest/ogr/ogr_gml.py
@@ -4626,3 +4626,18 @@ def test_ogr_gml_get_layers_by_name_from_imported_schema_more_tests(tmp_path):
     assert isinstance(
         dat_erst, list
     ), f"Expected 'dat_erst' to be of type 'list', but got {type(dat_erst)}"
+
+
+###############################################################################
+# Test force opening a GML file
+
+
+def test_ogr_gml_force_opening(tmp_vsimem):
+
+    filename = str(tmp_vsimem / "test.gml")
+    gdal.FileFromMemBuffer(filename, open("data/nas/empty_nas.xml", "rb").read())
+
+    # Would be opened by NAS driver if not forced
+    with gdal.config_option("NAS_GFS_TEMPLATE", ""):
+        ds = gdal.OpenEx(filename, allowed_drivers=["GML"])
+        assert ds.GetDriver().GetDescription() == "GML"
diff --git a/ogr/ogrsf_frmts/gml/ogrgmldriver.cpp b/ogr/ogrsf_frmts/gml/ogrgmldriver.cpp
index 9f633360c769..c180c298388b 100644
--- a/ogr/ogrsf_frmts/gml/ogrgmldriver.cpp
+++ b/ogr/ogrsf_frmts/gml/ogrgmldriver.cpp
@@ -75,6 +75,9 @@ static int OGRGMLDriverIdentify(GDALOpenInfo *poOpenInfo)
         if (!poOpenInfo->TryToIngest(4096))
             return FALSE;
 
+        if (poOpenInfo->IsSingleAllowedDriver("GML"))
+            return TRUE;
+
         return OGRGMLDataSource::CheckHeader(
             reinterpret_cast<const char *>(poOpenInfo->pabyHeader));
     }