Postgres: avoid stripping backslashes when reading string list

autotest/ogr/ogr_pg.py

@@ -6429,3 +6429,24 @@ def test_ogr_pg_geometry_intersection_spatial_filter(
         assert f.GetGeometryRef().ExportToWkt() == "POINT (0.5 0.5)"
         f = sql_lyr.GetNextFeature()
         assert f is None
+
+
+###############################################################################
+# Test backslash characters are properly read when reading string lists
+
+
+@only_without_postgis
+def test_ogr_pg_string_list_escaping(pg_ds):
+
+    paths = [r"c:\data", r'c:\"Program Files"']
+
+    lyr = pg_ds.CreateLayer("paths")
+    lyr.CreateField(ogr.FieldDefn("txt", ogr.OFTStringList))
+    f = ogr.Feature(lyr.GetLayerDefn())
+    f["txt"] = paths
+    lyr.CreateFeature(f)
+
+    lyr.ResetReading()
+
+    f_out = lyr.GetNextFeature()
+    assert f_out["txt"] == paths

autotest/ogr/ogr_pgdump.py

@@ -1673,3 +1673,32 @@ def check_and_remove(needle):
         sql = sql[sql.find(needle) + len(needle) :]
 
     check_and_remove(") ON CONFLICT DO NOTHING;")
+
+
+###############################################################################
+# Test that " and \ in string list items are escaped in both COPY and INSERT mode
+
+
+@pytest.mark.parametrize("pg_use_copy", ["YES", "NO"])
+def test_ogr_pgdump_stringlist_escaping(tmp_vsimem, pg_use_copy):
+
+    with gdaltest.config_option("PG_USE_COPY", pg_use_copy):
+        ds = ogr.GetDriverByName("PGDump").CreateDataSource(
+            tmp_vsimem / "ogr_pgdump_stringlist_escape.sql"
+        )
+        lyr = ds.CreateLayer("testlayer", geom_type=ogr.wkbNone)
+        lyr.CreateField(ogr.FieldDefn("stringlist", ogr.OFTStringList))
+
+        feat = ogr.Feature(lyr.GetLayerDefn())
+        feat.SetFieldStringList(0, ["a\\b", 'c"d'])
+        lyr.CreateFeature(feat)
+        ds = None
+
+    f = gdal.VSIFOpenL(tmp_vsimem / "ogr_pgdump_stringlist_escape.sql", "rb")
+    sql = gdal.VSIFReadL(1, 10000, f).decode("utf8")
+    gdal.VSIFCloseL(f)
+
+    if pg_use_copy == "YES":
+        assert r'{"a\\\\b","c\\"d"}' in sql, sql
+    else:
+        assert "ARRAY['a\\b','c\"d']" in sql, sql

ogr/ogrsf_frmts/pg/ogrpglayer.cpp

@@ -404,11 +404,14 @@ static void OGRPGTokenizeStringListUnescapeToken(char *pszToken)
     }
 
     int iSrc = 0, iDst = 0;
-    for (iSrc = 0; pszToken[iSrc] != '\0'; iSrc++)
+    while (pszToken[iSrc] != '\0')
     {
         pszToken[iDst] = pszToken[iSrc];
-        if (pszToken[iSrc] != '\\')
-            iDst++;
+        if (pszToken[iSrc] == '\\' && pszToken[iSrc + 1] != '\0')
+        {
+            iSrc++;
+        }
+        pszToken[iDst++] = pszToken[iSrc++];
     }
     pszToken[iDst] = '\0';
 }

ogr/ogrsf_frmts/pgdump/ogrpgdumplayer.cpp

@@ -979,7 +979,7 @@ OGRPGDumpEscapeStringList(char **papszItems, bool bForInsertOrUpdate,
 
                 while (*pszStr)
                 {
-                    if (*pszStr == '"')
+                    if (*pszStr == '"' || *pszStr == '\\')
                         osStr += "\\";
                     osStr += *pszStr;
                     pszStr++;