From d257c8c0ceeb57cff3cafcbb4526462839de887e Mon Sep 17 00:00:00 2001
From: Robin Gareus <robin@gareus.org>
Date: Sun, 8 Sep 2024 01:33:57 +0200
Subject: [PATCH] Prevent endless recursive directory scans

This can happen when a folder symlinks to itself or subfolders
in some similar recursive pattern.
---
 libs/pbd/file_utils.cc | 27 +++++++++++++++++----------
 1 file changed, 17 insertions(+), 10 deletions(-)

diff --git a/libs/pbd/file_utils.cc b/libs/pbd/file_utils.cc
index 4714bbc741..cf1f8ec832 100644
--- a/libs/pbd/file_utils.cc
+++ b/libs/pbd/file_utils.cc
@@ -22,6 +22,7 @@
 
 #include <algorithm>
 #include <climits>
+#include <set>
 #include <vector>
 
 #include <glib.h>
@@ -80,7 +81,8 @@ run_functor_for_paths (vector<string>& result,
                        void *arg,
                        bool pass_files_only,
                        bool pass_fullpath, bool return_fullpath,
-                       bool recurse)
+                       bool recurse,
+                       set<string>& scanned_paths)
 {
 	for (vector<string>::const_iterator i = paths.begin(); i != paths.end(); ++i) {
 		try
@@ -102,11 +104,12 @@ run_functor_for_paths (vector<string>& result,
 				bool is_dir = Glib::file_test (fullpath, Glib::FILE_TEST_IS_DIR);
 
 				if (is_dir && recurse) {
-					DEBUG_TRACE (DEBUG::FileUtils,
-							string_compose("Descending into directory:  %1\n",
-								fullpath));
-					run_functor_for_paths (result, fullpath, functor, arg, pass_files_only,
-					                       pass_fullpath, return_fullpath, recurse);
+					if (scanned_paths.find (fullpath) == scanned_paths.end ()) {
+						scanned_paths.insert (fullpath);
+						DEBUG_TRACE (DEBUG::FileUtils, string_compose("Descending into directory:  %1\n", fullpath));
+						run_functor_for_paths (result, fullpath, functor, arg, pass_files_only,
+						                       pass_fullpath, return_fullpath, recurse, scanned_paths);
+					}
 				}
 
 				if (is_dir && pass_files_only) {
@@ -163,8 +166,9 @@ get_paths (vector<string>& result,
            bool files_only,
            bool recurse)
 {
+	set<string> scanned_path;
 	run_functor_for_paths (result, paths, accept_all_files, 0,
-	                       files_only, true, true, recurse);
+	                       files_only, true, true, recurse, scanned_path);
 }
 
 void
@@ -186,9 +190,10 @@ find_files_matching_pattern (vector<string>& result,
                              const Searchpath& paths,
                              const Glib::PatternSpec& pattern)
 {
+	set<string> unused;
 	run_functor_for_paths (result, paths, pattern_filter,
 	                       const_cast<Glib::PatternSpec*>(&pattern),
-	                       true, false, true, false);
+	                       true, false, true, false, unused);
 }
 
 void
@@ -281,7 +286,8 @@ find_paths_matching_filter (vector<string>& result,
                             bool pass_fullpath, bool return_fullpath,
                             bool recurse)
 {
-	run_functor_for_paths (result, paths, filter, arg, false, pass_fullpath, return_fullpath, recurse);
+	set<string> scanned_path;
+	run_functor_for_paths (result, paths, filter, arg, false, pass_fullpath, return_fullpath, recurse, scanned_path);
 }
 
 void
@@ -292,7 +298,8 @@ find_files_matching_filter (vector<string>& result,
                             bool pass_fullpath, bool return_fullpath,
                             bool recurse)
 {
-	run_functor_for_paths (result, paths, filter, arg, true, pass_fullpath, return_fullpath, recurse);
+	set<string> scanned_path;
+	run_functor_for_paths (result, paths, filter, arg, true, pass_fullpath, return_fullpath, recurse, scanned_path);
 }
 
 bool