libcamera: pipeline_handler: Make lock() and unlock() thread-safe

The PipelineHandler lock() and unlock() functions are documented as
thread-safe, but they're not. Fix them using a mutex.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/include/libcamera/internal/pipeline_handler.h b/include/libcamera/internal/pipeline_handler.h
index fc6d476b..b473eb70 100644
--- a/include/libcamera/internal/pipeline_handler.h
+++ b/include/libcamera/internal/pipeline_handler.h
@@ -14,6 +14,7 @@
 #include <vector>
 
 #include <libcamera/base/object.h>
+#include <libcamera/base/thread.h>
 
 #include <libcamera/controls.h>
 #include <libcamera/stream.h>
@@ -73,6 +74,8 @@ protected:
 	CameraManager *manager_;
 
 private:
+	void unlockLocked();
+
 	void mediaDeviceDisconnected(MediaDevice *media);
 	virtual void disconnect();
 
@@ -81,6 +84,7 @@ private:
 
 	const char *name_;
 
+	Mutex lock_;
 	bool lockOwner_;
 
 	friend class PipelineHandlerFactory;