From b1773aba10d9969c6bf34627bb6cef3953cfe5e6 Mon Sep 17 00:00:00 2001
From: Maxence Lange <maxence@artificial-owl.com>
Date: Wed, 23 Sep 2026 11:59:55 -0100
Subject: [PATCH] fix(federation): fix shares and mount rename

Signed-off-by: Maxence Lange <maxence@artificial-owl.com>
---
 lib/MountManager/CircleMountProvider.php | 87 +++++++++---------------
 1 file changed, 33 insertions(+), 54 deletions(-)

diff --git a/lib/MountManager/CircleMountProvider.php b/lib/MountManager/CircleMountProvider.php
index 980a26d6a..7f8ab2ca4 100644
--- a/lib/MountManager/CircleMountProvider.php
+++ b/lib/MountManager/CircleMountProvider.php
@@ -18,7 +18,6 @@
 use OCA\Circles\Exceptions\MountPointConstructionException;
 use OCA\Circles\Exceptions\RequestBuilderException;
 use OCA\Circles\Exceptions\SingleCircleNotFoundException;
-use OCA\Circles\IFederatedUser;
 use OCA\Circles\Model\Member;
 use OCA\Circles\Model\Mount;
 use OCA\Circles\Model\Mountpoint;
@@ -29,10 +28,8 @@
 use OCP\DB\Exception;
 use OCP\Federation\ICloudIdManager;
 use OCP\Files\Config\IMountProvider;
-use OCP\Files\Folder;
 use OCP\Files\IRootFolder;
 use OCP\Files\Mount\IMountPoint;
-use OCP\Files\NotFoundException;
 use OCP\Files\Storage\IStorageFactory;
 use OCP\Http\Client\IClientService;
 use OCP\IUser;
@@ -42,6 +39,7 @@ class CircleMountProvider implements IMountProvider {
 	use TArrayTools;
 
 	public const EXTERNAL_STORAGE = ExternalStorage::class;
+	public array $mountedPoint = [];
 
 	public function __construct(
 		private IClientService $clientService,
@@ -188,63 +186,44 @@ private function fixDuplicateFile(string $userId, Mount $mount): void {
 			return;
 		}
 
-		$fs = $this->rootFolder->getUserFolder($userId);
-
-		try {
-			$fs->get($mount->getMountPoint());
-		} catch (NotFoundException) {
-			// in case no alternate mountpoint, we generate one in database (easier to catch duplicate mountpoint)
-			if ($mount->getAlternateMountPoint() !== null) {
-				return;
-			}
-
-			$federatedUser = $this->federatedUserService->getLocalFederatedUser($userId);
-			$mountPoint = new Mountpoint($mount->getMountId(), $federatedUser->getSingleId(), $mount->getOriginalMountPoint());
-			try {
-				$this->mountPointRequest->insert($mountPoint);
-				return;
-			} catch (Exception $e) {
-				// meaning a duplicate mountpoint already exists, we need to set a new filename
-				if ($e->getReason() !== Exception::REASON_UNIQUE_CONSTRAINT_VIOLATION) {
-					throw $e;
-				}
-			}
+		// we will be using cache version of the filesystem, to not cycle while operating it
+		$mountId = $mount->getId();
+		$baseFile = $mountPoint = '/files' . $mount->getMountPoint();
+		$parentMount = $this->rootFolder->getUserFolder($userId)->getMountPoint();
+		$parentCache = $parentMount->getStorage()->getCache();
+
+		// splitting extension to have a nice /file (1).ext
+		$ext = pathinfo($mountPoint, PATHINFO_EXTENSION);
+		if ($ext !== '') {
+			$baseFile = substr($mountPoint, 0, -(strlen($ext) + 1));
+			$ext = '.' . $ext;
 		}
 
-		$federatedUser = $this->federatedUserService->getLocalFederatedUser($userId);
-		$this->generateIncrementedMountpoint($fs, $mount, $federatedUser);
-	}
+		// based on cached content, improving naming
+		$n = 1;
+		while ($parentCache->inCache($mountPoint)
+			|| ($this->mountedPoint[$mountPoint] ?? $mountId) !== $mountId) {
+			$mountPoint = $baseFile . ' (' . $n++ . ')' . $ext;
+		}
 
-	private function generateIncrementedMountpoint(Folder $fs, Mount $mount, IFederatedUser $federatedUser): void {
-		$info = pathinfo($mount->getMountPoint());
-		$filename = rtrim($this->get('dirname', $info), '/') . '/' . $this->get('filename', $info);
-		$extension = $this->get('extension', $info);
-		$extension = ($extension === '') ? '' : '.' . $extension;
+		// we keep trace as this won't be available in cache
+		$this->mountedPoint[$mountPoint] = $mount->getId();
 
-		$n = 2;
-		while (true) {
-			$path = $filename . " ($n)" . $extension;
+		$federatedUser = $this->federatedUserService->getLocalFederatedUser($userId);
+		$mountPoint = new Mountpoint($mount->getMountId(), $federatedUser->getSingleId(), substr($mountPoint, 6));
+		try {
 			try {
-				$fs->get($path);
-			} catch (NotFoundException) {
-				$mountPoint = new Mountpoint($mount->getMountId(), $federatedUser->getSingleId(), $path);
-				$mount->setAlternateMountPoint($mountPoint);
-				try {
-					try {
-						$this->mountPointRequest->update($mountPoint);
-					} catch (MountNotFoundException) {
-						$this->mountPointRequest->insert($mountPoint);
-					}
-					return;
-				} catch (Exception $e) {
-					// meaning path is already used by another share for this user, we keep incrementing
-					if ($e->getReason() !== Exception::REASON_UNIQUE_CONSTRAINT_VIOLATION) {
-						throw $e;
-					}
-				}
+				$this->mountPointRequest->update($mountPoint);
+			} catch (MountNotFoundException) {
+				$this->mountPointRequest->insert($mountPoint);
+			}
+			return;
+		} catch (Exception $e) {
+			$this->logger->error('issue while creating alternate mount point', ['exception' => $e]);
+			// while there should be no reason for a unique constraint violation, we just log and ignore it
+			if ($e->getReason() !== Exception::REASON_UNIQUE_CONSTRAINT_VIOLATION) {
+				throw $e;
 			}
-
-			$n++;
 		}
 	}
 }