From 5e1daf999b11f8c3bc314aebf74c4469aec602cf Mon Sep 17 00:00:00 2001
From: BLumia <wangzichong@deepin.org>
Date: Thu, 3 Sep 2026 10:59:08 +0800
Subject: [PATCH] fix: fsync autostart file to survive hard reboot
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1. Root cause: saveAutostartEntry only called QFile::flush() after
   writing the autostart desktop file, which flushes Qt's internal
   buffer to the OS fd but leaves data in the page cache. A hard
   reboot before the OS flushes the page cache loses the file
   content, causing the autostart entry to be empty or missing.
2. Fix: call ::fsync() on the file descriptor after flush() to
   force data to physical disk, and fsync the parent directory to
   persist the directory entry for newly created files.
3. Impact: no signature or return-value change; fsync failure only
   logs a warning without altering existing behavior. All callers
   remain compatible.

Log: ensure autostart desktop files persist across hard reboots

Influence:
1. Test setting autostart then hard reboot, verify autostart works
2. Test cancel-disk-encryption interrupted by hard reboot, verify
   the resume dialog appears after reboot
3. Verify normal autostart enable/disable has no regression

fix: 修复自启动文件硬重启后未落盘的问题

1. 根因：saveAutostartEntry 写入 autostart desktop 文件后仅调用
   QFile::flush()，该操作只将 Qt 内部缓冲刷到 OS fd，数据仍停留
  在 page cache 中。硬重启时 page cache 丢失，导致文件内容为空
  或不完整，自启动条目失效。
2. 方案：在 flush() 成功后对文件描述符调用 ::fsync() 强制数据
   写入物理磁盘，并对父目录做 fsync 确保新文件目录项持久化。
3. 影响：不改变函数签名和返回值语义；fsync 失败仅记录警告不
   改变现有行为，所有调用者保持兼容。

Log: 确保自启动 desktop 文件在硬重启后不丢失

Influence:
1. 测试设置自启动后硬重启，验证自启动正常生效
2. 测试取消分区加密过程中硬重启，验证重启后继续取消加密
   对话框正常弹出
3. 验证正常的自启动启用/禁用功能无回归

PMS: BUG-375555
---
 src/dbus/applicationservice.cpp | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/src/dbus/applicationservice.cpp b/src/dbus/applicationservice.cpp
index e72b0588..95d42498 100644
--- a/src/dbus/applicationservice.cpp
+++ b/src/dbus/applicationservice.cpp
@@ -28,6 +28,7 @@
 #include <QUrl>
 #include <QUuid>
 #include <algorithm>
+#include <fcntl.h>
 #include <new>
 #include <qcontainerfwd.h>
 #include <qdbuserror.h>
@@ -35,6 +36,7 @@
 #include <qlogging.h>
 #include <qnamespace.h>
 #include <qtmetamacros.h>
+#include <unistd.h>
 #include <utility>
 #include <wordexp.h>
 
@@ -1037,6 +1039,23 @@ bool ApplicationService::saveAutostartEntry(const QString &fileName, const Deskt
         return false;
     }
 
+    // Ensure file content is flushed to physical disk so the autostart entry
+    // survives a hard reboot (BUG-375555).
+    if (autostartFile.handle() != -1) {
+        if (::fsync(autostartFile.handle()) != 0) {
+            qWarning() << "fsync autostart file failed:" << fileName;
+        }
+    }
+
+    // Sync the parent directory so the directory entry of a newly created file
+    // is also persisted to disk.
+    const QByteArray parentDirPath = autostartFileInfo.absolutePath().toLocal8Bit();
+    int dirFd = ::open(parentDirPath.constData(), O_RDONLY | O_DIRECTORY);
+    if (dirFd != -1) {
+        ::fsync(dirFd);
+        ::close(dirFd);
+    }
+
     return true;
 }