[libcamera-devel] [PATCH 09/31] libcamera: controls: Decouple control and value type in ControlList::set()

[Laurent Pinchart]

The ControlList::set() method takes a reference to a Control<T>, and
requires the value to be a reference to T. This prevents the set()
method to be used with value types that are convertible to T,
and in particular with std::array or std::vector values types when the
Control type will be a Span<> to support compound controls.

Fix this by decoupling the control type and value type in the template
parameters. The compiler will still catch invalid conversions, including
cases where constructor a T from the value type is explicit.

Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
---
 include/libcamera/controls.h | 4 ++--
 src/libcamera/controls.cpp   | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/include/libcamera/controls.h b/include/libcamera/controls.h
index 9f8a9031bd74..9d93064c11b2 100644
--- a/include/libcamera/controls.h
+++ b/include/libcamera/controls.h
@@ -223,8 +223,8 @@ public:
 		return val->get<T>();
 	}
 
-	template<typename T>
-	void set(const Control<T> &ctrl, const T &value)
+	template<typename T, typename V>
+	void set(const Control<T> &ctrl, const V &value)
 	{
 		ControlValue *val = find(ctrl.id());
 		if (!val)
diff --git a/src/libcamera/controls.cpp b/src/libcamera/controls.cpp
index f632d60adc8b..a136ebd2653b 100644
--- a/src/libcamera/controls.cpp
+++ b/src/libcamera/controls.cpp
@@ -735,7 +735,7 @@ bool ControlList::contains(unsigned int id) const
  */
 
 /**
- * \fn template<typename T> void ControlList::set(const Control<T> &ctrl, const T &value)
+ * \fn template<typename T, typename V> void ControlList::set(const Control<T> &ctrl, const V &value)
  * \brief Set the control \a ctrl value to \a value
  * \param[in] ctrl The control
  * \param[in] value The control value
-- 
Regards,

Laurent Pinchart