From 57362f4b52a2479a9c4b60cd4a91b7c876027335 Mon Sep 17 00:00:00 2001
From: Erik Kunze <github1@erik-kunze.de>
Date: Fri, 22 Nov 2024 15:38:29 +0100
Subject: [PATCH] The test for additional switches to the LIST command must be
 performed before the path is joined. Otherwise, the path will never be empty
 and the test will be skipped. Fixes ENODEV error (FTP/550) on clients using
 "LIST -a".

---
 source/ftpSession.cpp | 35 ++++++++++++++++++-----------------
 1 file changed, 18 insertions(+), 17 deletions(-)

diff --git a/source/ftpSession.cpp b/source/ftpSession.cpp
index 82fb927..6c1d6c8 100644
--- a/source/ftpSession.cpp
+++ b/source/ftpSession.cpp
@@ -1230,26 +1230,27 @@ void FtpSession::xferDir (char const *const args_, XferDirMode const mode_, bool
 	if (std::strlen (args_) > 0)
 	{
 		// an argument was provided
+
+		// work around broken clients that think LIST -a/-l is valid
+		if (workaround_)
+		{
+			if (args_[0] == '-' && (args_[1] == 'a' || args_[1] == 'l'))
+			{
+				char const *args = &args_[2];
+				if (*args == '\0' || *args == ' ')
+				{
+					if (*args == ' ')
+						++args;
+
+					xferDir (args, mode_, false);
+					return;
+				}
+			}
+		}
+
 		auto const path = buildResolvedPath (m_cwd, args_);
 		if (path.empty ())
 		{
-			// work around broken clients that think LIST -a/-l is valid
-			if (workaround_)
-			{
-				if (args_[0] == '-' && (args_[1] == 'a' || args_[1] == 'l'))
-				{
-					char const *args = &args_[2];
-					if (*args == '\0' || *args == ' ')
-					{
-						if (*args == ' ')
-							++args;
-
-						xferDir (args, mode_, false);
-						return;
-					}
-				}
-			}
-
 			sendResponse ("550 %s\r\n", std::strerror (errno));
 			setState (State::COMMAND, true, true);
 			return;