diff --git a/lib/private/Lock/MemcacheLockingProvider.php b/lib/private/Lock/MemcacheLockingProvider.php index 70ad972b46..55a82b2278 100644 --- a/lib/private/Lock/MemcacheLockingProvider.php +++ b/lib/private/Lock/MemcacheLockingProvider.php @@ -72,12 +72,12 @@ class MemcacheLockingProvider extends AbstractLockingProvider { public function acquireLock(string $path, int $type) { if ($type === self::LOCK_SHARED) { if (!$this->memcache->inc($path)) { - throw new LockedException($path); + throw new LockedException($path, null, $this->getExistingLockForException($path)); } } else { $this->memcache->add($path, 0); if (!$this->memcache->cas($path, 0, 'exclusive')) { - throw new LockedException($path); + throw new LockedException($path, null, $this->getExistingLockForException($path)); } } $this->setTTL($path); @@ -115,15 +115,26 @@ class MemcacheLockingProvider extends AbstractLockingProvider { public function changeLock(string $path, int $targetType) { if ($targetType === self::LOCK_SHARED) { if (!$this->memcache->cas($path, 'exclusive', 1)) { - throw new LockedException($path); + throw new LockedException($path, null, $this->getExistingLockForException($path)); } } else if ($targetType === self::LOCK_EXCLUSIVE) { // we can only change a shared lock to an exclusive if there's only a single owner of the shared lock if (!$this->memcache->cas($path, 1, 'exclusive')) { - throw new LockedException($path); + throw new LockedException($path, null, $this->getExistingLockForException($path)); } } $this->setTTL($path); $this->markChange($path, $targetType); } + + private function getExistingLockForException($path) { + $existing = $this->memcache->get($path); + if (!$existing) { + return 'none'; + } else if ($existing === 'exclusive') { + return $existing; + } else { + return $existing . ' shared locks'; + } + } } diff --git a/lib/public/Lock/LockedException.php b/lib/public/Lock/LockedException.php index 1378f437c3..b4038f8dd5 100644 --- a/lib/public/Lock/LockedException.php +++ b/lib/public/Lock/LockedException.php @@ -46,11 +46,15 @@ class LockedException extends \Exception { * * @param string $path locked path * @param \Exception|null $previous previous exception for cascading - * + * @param string $existingLock since 14.0.0 * @since 8.1.0 */ - public function __construct(string $path, \Exception $previous = null) { - parent::__construct('"' . $path . '" is locked', 0, $previous); + public function __construct(string $path, \Exception $previous = null, string $existingLock = null) { + $message = '"' . $path . '" is locked'; + if ($existingLock) { + $message .= ', existing lock on file: ' . $existingLock; + } + parent::__construct($message, 0, $previous); $this->path = $path; }