appFs - umount mountPoint before directory status checking to prevent…

… access failure

If tryToUnmountOnStart is true, code now attempts to unmount the specified mount point.
This is necessary because if the application terminates unexpectedly, the filesystem
might remain mounted, which can prevent proper status checking and cause subsequent
attempts to mount it to fail. By forcing an unmount here, we ensure the mount point is
in a clean state before proceeding. If the unmount fails, an exception is thrown to
indicate that the cleanup process was unsuccessful.

src/appFs/appFs.cpp

@@ -388,6 +388,22 @@ AppFsFuse::AppFsFuse(
 	struct fuse_operations fuseOps = {};
 	setFuseOperations(&fuseOps);
 
+	/**
+	 * If tryToUnmountOnStart is true, this code attempts to unmount the specified mount point.
+	 * This is necessary because if the application terminates unexpectedly, the filesystem
+	 * might remain mounted, which can prevent proper status checking and cause subsequent
+	 * attempts to mount it to fail. By forcing an unmount here, we ensure the mount point is
+	 * in a clean state before proceeding. If the unmount fails, an exception is thrown to
+	 * indicate that the cleanup process was unsuccessful.
+	 */
+	if (tryToUnmountOnStart) {
+		const int ret = umount2(mountPoint.c_str(), MNT_FORCE | UMOUNT_NOFOLLOW);
+		if (ret < 0 && errno != ENOENT) { // ENOENT means that No such directory exists
+			throw std::runtime_error(
+				"umount of " + mountPoint + " has failed. Error: " + std::to_string(errno));
+		}
+	}
+
 	if (createMountPoint) {
 		createDirectories(mountPoint);
 	}
@@ -397,19 +413,7 @@ AppFsFuse::AppFsFuse(
 		throw std::runtime_error("fuse_new() has failed.");
 	}
 
-	int ret = fuse_mount(m_fuse.get(), mountPoint.c_str());
-	if (ret < 0 && tryToUnmountOnStart) {
-		ret = umount2(mountPoint.c_str(), MNT_FORCE | UMOUNT_NOFOLLOW);
-		if (ret < 0) {
-			throw std::runtime_error("umount of " + mountPoint + " has failed.");
-		}
-
-		ret = fuse_mount(m_fuse.get(), mountPoint.c_str());
-		if (ret < 0) {
-			throw std::runtime_error("fuse_mount() has failed again.");
-		}
-	}
-
+	const int ret = fuse_mount(m_fuse.get(), mountPoint.c_str());
 	if (ret < 0) {
 		throw std::runtime_error("fuse_mount() has failed.");
 	}