[v2,26/42] libcamera: value_node: Add functions to erase child nodes
diff mbox series

Message ID 20260407153427.1825999-27-laurent.pinchart@ideasonboard.com
State New
Headers show
Series
  • libcamera: Global configuration file improvements
Related show

Commit Message

Laurent Pinchart April 7, 2026, 3:34 p.m. UTC
There will be a need to erase child nodes when implementing support for
overriding configuration options. Add two erase() functions to the
ValueNode class, mimicking the add() API.

More erase() overloads could be added, for instance taking iterators as
parameters, to improve efficiency. This should be considered later, when
usage of the ValueNode class will expand, based on the actual usage
patterns.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
---
 include/libcamera/internal/value_node.h |  3 ++
 src/libcamera/value_node.cpp            | 51 +++++++++++++++++++++++++
 2 files changed, 54 insertions(+)

Patch
diff mbox series

diff --git a/include/libcamera/internal/value_node.h b/include/libcamera/internal/value_node.h
index 14c5e0eb0202..4e3757af7d09 100644
--- a/include/libcamera/internal/value_node.h
+++ b/include/libcamera/internal/value_node.h
@@ -244,6 +244,9 @@  public:
 	ValueNode *add(std::initializer_list<std::string_view> path,
 		       std::unique_ptr<ValueNode> &&child);
 
+	void erase(const std::string &key);
+	void erase(std::initializer_list<std::string_view> path);
+
 private:
 	LIBCAMERA_DISABLE_COPY_AND_MOVE(ValueNode)
 
diff --git a/src/libcamera/value_node.cpp b/src/libcamera/value_node.cpp
index 990e46d70358..8a1af13a5d6e 100644
--- a/src/libcamera/value_node.cpp
+++ b/src/libcamera/value_node.cpp
@@ -621,4 +621,55 @@  ValueNode *ValueNode::add(std::initializer_list<std::string_view> path,
 	return node;
 }
 
+/**
+ * \brief Erase a child node in a dictionary
+ * \param[in] key The dictionary key
+ *
+ * Erase the child node referenced by \a key in a dictionary node. If the \a
+ * key does not exist, or if this node is not a dictionary, the function
+ * returns without performing any operation.
+ */
+void ValueNode::erase(const std::string &key)
+{
+	auto node = dictionary_.extract(key);
+	if (node.empty())
+		return;
+
+	for (auto iter = list_.begin(); iter != list_.end(); ++iter) {
+		if (iter->value.get() != node.mapped())
+			continue;
+
+		list_.erase(iter);
+		return;
+	}
+}
+
+/**
+ * \brief Erase the child node at the given path
+ * \param[in] path The path
+ *
+ * Erase the child node at the given \a path. If no child node exists for the
+ * path, the function returns without performing any operation.
+ */
+void ValueNode::erase(std::initializer_list<std::string_view> path)
+{
+	if (!path.size())
+		return;
+
+	ValueNode *node = this;
+
+	for (const auto [i, name] : utils::enumerate(path)) {
+		if (i == path.size() - 1) {
+			node->erase(std::string{ name });
+			return;
+		}
+
+		auto iter = node->dictionary_.find(name);
+		if (iter == node->dictionary_.end())
+			return;
+
+		node = iter->second;
+	}
+}
+
 } /* namespace libcamera */