From de97a682f228b52e32411f6abee51ffc1b00ac9e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Barnab=C3=A1s=20P=C5=91cze?= <pobrn@protonmail.com>
Date: Sat, 12 Jul 2025 16:44:31 +0200
Subject: [PATCH] spa: libcamera: use lock when acquiring `CameraManager`

Make `libcamera_manager_acquire()` thread safe by locking a mutex
when the `CameraManager` instance is created and started.

(cherry picked from commit 5f4f4b5dd31130501ea3ce3198065c0744cf5fa3)
---
 spa/plugins/libcamera/libcamera-manager.cpp | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/spa/plugins/libcamera/libcamera-manager.cpp b/spa/plugins/libcamera/libcamera-manager.cpp
index db2c73d54..648ea1fe5 100644
--- a/spa/plugins/libcamera/libcamera-manager.cpp
+++ b/spa/plugins/libcamera/libcamera-manager.cpp
@@ -82,10 +82,13 @@ struct impl {
 
 }
 
-static std::weak_ptr<CameraManager> global_manager;
-
 std::shared_ptr<CameraManager> libcamera_manager_acquire(int& res)
 {
+	static std::weak_ptr<CameraManager> global_manager;
+	static std::mutex lock;
+
+	std::lock_guard guard(lock);
+
 	if (auto manager = global_manager.lock())
 		return manager;