From 8268c61b9f841c7e7e900a90223a43b2126fadbb Mon Sep 17 00:00:00 2001
From: sfan5 <sfan5@live.de>
Date: Wed, 5 Jun 2024 22:58:33 +0200
Subject: [PATCH] Make safeWriteToFile safe for thread-concurrent use
---
src/filesys.cpp | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/src/filesys.cpp b/src/filesys.cpp
index a61f7f0aa..26cdaba07 100644
--- a/src/filesys.cpp
+++ b/src/filesys.cpp
@@ -25,6 +25,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
#include <cstring>
#include <cerrno>
#include <fstream>
+#include <atomic>
#include "log.h"
#include "config.h"
#include "porting.h"
@@ -854,10 +855,12 @@ const char *GetFilenameFromPath(const char *path)
return filename ? filename + 1 : path;
}
+// Note: this is not safe if two MT processes try this at the same time (FIXME?)
bool safeWriteToFile(const std::string &path, std::string_view content)
{
- // Note: this is not safe if two MT processes try this at the same time (FIXME?)
- const std::string tmp_file = path + ".~mt";
+ // Prevent two threads from writing to the same temporary file
+ static std::atomic<u16> g_file_counter;
+ const std::string tmp_file = path + ".~mt" + itos(g_file_counter.fetch_add(1));
// Write data to a temporary file
std::string write_error;