[PATCH v1] treewide: Remove top-level `const` from return types

Barnabás Pőcze barnabas.pocze at ideasonboard.com
Tue Jun 3 13:14:34 CEST 2025


Top-level `const` qualifiers are not useful, so avoid them. This is done
either by simply removing the top-level `const`, or making the function
return a reference to const where that is appropriate.

Signed-off-by: Barnabás Pőcze <barnabas.pocze at ideasonboard.com>
---
 include/libcamera/base/log.h                  | 2 +-
 include/libcamera/geometry.h                  | 6 +++---
 include/libcamera/internal/matrix.h           | 2 +-
 include/libcamera/internal/v4l2_subdevice.h   | 2 +-
 include/libcamera/internal/v4l2_videodevice.h | 2 +-
 src/apps/cam/drm.h                            | 4 ++--
 src/ipa/libipa/histogram.h                    | 2 +-
 src/libcamera/geometry.cpp                    | 6 +++---
 src/libcamera/pipeline/ipu3/ipu3.cpp          | 2 +-
 src/libcamera/pipeline/mali-c55/mali-c55.cpp  | 8 ++++----
 src/libcamera/v4l2_subdevice.cpp              | 2 +-
 src/libcamera/v4l2_videodevice.cpp            | 2 +-
 12 files changed, 20 insertions(+), 20 deletions(-)

diff --git a/include/libcamera/base/log.h b/include/libcamera/base/log.h
index 8af74b59d..5a232a650 100644
--- a/include/libcamera/base/log.h
+++ b/include/libcamera/base/log.h
@@ -75,7 +75,7 @@ public:
 	const LogCategory &category() const { return category_; }
 	const std::string &fileInfo() const { return fileInfo_; }
 	const std::string &prefix() const { return prefix_; }
-	const std::string msg() const { return msgStream_.str(); }
+	std::string msg() const { return msgStream_.str(); }
 
 private:
 	LIBCAMERA_DISABLE_COPY_AND_MOVE(LogMessage)
diff --git a/include/libcamera/geometry.h b/include/libcamera/geometry.h
index f322e3d5b..d9378efec 100644
--- a/include/libcamera/geometry.h
+++ b/include/libcamera/geometry.h
@@ -31,7 +31,7 @@ public:
 	int x;
 	int y;
 
-	const std::string toString() const;
+	std::string toString() const;
 
 	constexpr Point operator-() const
 	{
@@ -64,7 +64,7 @@ public:
 	unsigned int height;
 
 	bool isNull() const { return !width && !height; }
-	const std::string toString() const;
+	std::string toString() const;
 
 	Size &alignDownTo(unsigned int hAlignment, unsigned int vAlignment)
 	{
@@ -275,7 +275,7 @@ public:
 	unsigned int height;
 
 	bool isNull() const { return !width && !height; }
-	const std::string toString() const;
+	std::string toString() const;
 
 	Point center() const;
 
diff --git a/include/libcamera/internal/matrix.h b/include/libcamera/internal/matrix.h
index 47513b995..1842389f2 100644
--- a/include/libcamera/internal/matrix.h
+++ b/include/libcamera/internal/matrix.h
@@ -56,7 +56,7 @@ public:
 
 	~Matrix() = default;
 
-	const std::string toString() const
+	std::string toString() const
 	{
 		std::stringstream out;
 
diff --git a/include/libcamera/internal/v4l2_subdevice.h b/include/libcamera/internal/v4l2_subdevice.h
index fa2a4a21e..c1cde1df2 100644
--- a/include/libcamera/internal/v4l2_subdevice.h
+++ b/include/libcamera/internal/v4l2_subdevice.h
@@ -66,7 +66,7 @@ struct V4L2SubdeviceFormat {
 	Size size;
 	std::optional<ColorSpace> colorSpace;
 
-	const std::string toString() const;
+	std::string toString() const;
 };
 
 std::ostream &operator<<(std::ostream &out, const V4L2SubdeviceFormat &f);
diff --git a/include/libcamera/internal/v4l2_videodevice.h b/include/libcamera/internal/v4l2_videodevice.h
index ae6a76cb0..6caafc4dc 100644
--- a/include/libcamera/internal/v4l2_videodevice.h
+++ b/include/libcamera/internal/v4l2_videodevice.h
@@ -178,7 +178,7 @@ public:
 	std::array<Plane, 3> planes;
 	unsigned int planesCount = 0;
 
-	const std::string toString() const;
+	std::string toString() const;
 };
 
 std::ostream &operator<<(std::ostream &out, const V4L2DeviceFormat &f);
diff --git a/src/apps/cam/drm.h b/src/apps/cam/drm.h
index 1ba83b6eb..30a916d7e 100644
--- a/src/apps/cam/drm.h
+++ b/src/apps/cam/drm.h
@@ -97,9 +97,9 @@ public:
 
 	bool isImmutable() const { return flags_ & DRM_MODE_PROP_IMMUTABLE; }
 
-	const std::vector<uint64_t> values() const { return values_; }
+	const std::vector<uint64_t> &values() const { return values_; }
 	const std::map<uint32_t, std::string> &enums() const { return enums_; }
-	const std::vector<uint32_t> blobs() const { return blobs_; }
+	const std::vector<uint32_t> &blobs() const { return blobs_; }
 
 private:
 	Type type_;
diff --git a/src/ipa/libipa/histogram.h b/src/ipa/libipa/histogram.h
index a926002c8..8cf8bb6d1 100644
--- a/src/ipa/libipa/histogram.h
+++ b/src/ipa/libipa/histogram.h
@@ -36,7 +36,7 @@ public:
 	}
 
 	size_t bins() const { return cumulative_.size() - 1; }
-	const Span<const uint64_t> data() const { return cumulative_; }
+	Span<const uint64_t> data() const { return cumulative_; }
 	uint64_t total() const { return cumulative_[cumulative_.size() - 1]; }
 	uint64_t cumulativeFrequency(double bin) const;
 	double quantile(double q, uint32_t first = 0, uint32_t last = UINT_MAX) const;
diff --git a/src/libcamera/geometry.cpp b/src/libcamera/geometry.cpp
index 81cc8cd53..de76d0c12 100644
--- a/src/libcamera/geometry.cpp
+++ b/src/libcamera/geometry.cpp
@@ -53,7 +53,7 @@ namespace libcamera {
  * \brief Assemble and return a string describing the point
  * \return A string describing the point
  */
-const std::string Point::toString() const
+std::string Point::toString() const
 {
 	std::stringstream ss;
 	ss << *this;
@@ -133,7 +133,7 @@ std::ostream &operator<<(std::ostream &out, const Point &p)
  * \brief Assemble and return a string describing the size
  * \return A string describing the size
  */
-const std::string Size::toString() const
+std::string Size::toString() const
 {
 	std::stringstream ss;
 	ss << *this;
@@ -676,7 +676,7 @@ std::ostream &operator<<(std::ostream &out, const SizeRange &sr)
  * \brief Assemble and return a string describing the rectangle
  * \return A string describing the Rectangle
  */
-const std::string Rectangle::toString() const
+std::string Rectangle::toString() const
 {
 	std::stringstream ss;
 	ss << *this;
diff --git a/src/libcamera/pipeline/ipu3/ipu3.cpp b/src/libcamera/pipeline/ipu3/ipu3.cpp
index e31e3879d..ad20810e6 100644
--- a/src/libcamera/pipeline/ipu3/ipu3.cpp
+++ b/src/libcamera/pipeline/ipu3/ipu3.cpp
@@ -105,7 +105,7 @@ public:
 	Status validate() override;
 
 	const StreamConfiguration &cio2Format() const { return cio2Configuration_; }
-	const ImgUDevice::PipeConfig imguConfig() const { return pipeConfig_; }
+	const ImgUDevice::PipeConfig &imguConfig() const { return pipeConfig_; }
 
 	/* Cache the combinedTransform_ that will be applied to the sensor */
 	Transform combinedTransform_;
diff --git a/src/libcamera/pipeline/mali-c55/mali-c55.cpp b/src/libcamera/pipeline/mali-c55/mali-c55.cpp
index 4acc091bd..28d5da3c8 100644
--- a/src/libcamera/pipeline/mali-c55/mali-c55.cpp
+++ b/src/libcamera/pipeline/mali-c55/mali-c55.cpp
@@ -101,8 +101,8 @@ public:
 	int loadIPA();
 
 	/* Deflect these functionalities to either TPG or CameraSensor. */
-	const std::vector<Size> sizes(unsigned int mbusCode) const;
-	const Size resolution() const;
+	std::vector<Size> sizes(unsigned int mbusCode) const;
+	Size resolution() const;
 
 	int pixfmtToMbusCode(const PixelFormat &pixFmt) const;
 	const PixelFormat &bestRawFormat() const;
@@ -195,7 +195,7 @@ void MaliC55CameraData::setSensorControls(const ControlList &sensorControls)
 	delayedCtrls_->push(sensorControls);
 }
 
-const std::vector<Size> MaliC55CameraData::sizes(unsigned int mbusCode) const
+std::vector<Size> MaliC55CameraData::sizes(unsigned int mbusCode) const
 {
 	if (sensor_)
 		return sensor_->sizes(mbusCode);
@@ -218,7 +218,7 @@ const std::vector<Size> MaliC55CameraData::sizes(unsigned int mbusCode) const
 	return sizes;
 }
 
-const Size MaliC55CameraData::resolution() const
+Size MaliC55CameraData::resolution() const
 {
 	if (sensor_)
 		return sensor_->resolution();
diff --git a/src/libcamera/v4l2_subdevice.cpp b/src/libcamera/v4l2_subdevice.cpp
index 33279654d..e9c849ac5 100644
--- a/src/libcamera/v4l2_subdevice.cpp
+++ b/src/libcamera/v4l2_subdevice.cpp
@@ -923,7 +923,7 @@ const MediaBusFormatInfo &MediaBusFormatInfo::info(uint32_t code)
  * \brief Assemble and return a string describing the format
  * \return A string describing the V4L2SubdeviceFormat
  */
-const std::string V4L2SubdeviceFormat::toString() const
+std::string V4L2SubdeviceFormat::toString() const
 {
 	std::stringstream ss;
 	ss << *this;
diff --git a/src/libcamera/v4l2_videodevice.cpp b/src/libcamera/v4l2_videodevice.cpp
index d53aa2d3c..58a6704ef 100644
--- a/src/libcamera/v4l2_videodevice.cpp
+++ b/src/libcamera/v4l2_videodevice.cpp
@@ -429,7 +429,7 @@ bool V4L2BufferCache::Entry::operator==(const FrameBuffer &buffer) const
  * \brief Assemble and return a string describing the format
  * \return A string describing the V4L2DeviceFormat
  */
-const std::string V4L2DeviceFormat::toString() const
+std::string V4L2DeviceFormat::toString() const
 {
 	std::stringstream ss;
 	ss << *this;
-- 
2.49.0



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