libcamera: utils: Add set_overlap() function

The new set_overlap() function counts the number of overlapping elements
in the intersection of two sorted ranges defined by their beginning and
ending iterators.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>

1 files changed, 12 insertions, 0 deletions

diff --git a/src/libcamera/utils.cpp b/src/libcamera/utils.cpp
index cd0fd761..e38f3268 100644
--- a/src/libcamera/utils.cpp
+++ b/src/libcamera/utils.cpp
@@ -68,6 +68,18 @@ char *secure_getenv(const char *name)
  * \brief Constructs an object of type T and wraps it in a std::unique_ptr.
  */
 
+/**
+ * \fn libcamera::utils::set_overlap(InputIt1 first1, InputIt1 last1,
+ *				     InputIt2 first2, InputIt2 last2)
+ * \brief Count the number of elements in the intersection of two ranges
+ *
+ * Count the number of elements in the intersection of the sorted ranges [\a
+ * first1, \a last1) and [\a first1, \a last2). Elements are compared using
+ * operator< and the ranges must be sorted with respect to the same.
+ *
+ * \return The number of elements in the intersection of the two ranges
+ */
+
 } /* namespace utils */
 
 } /* namespace libcamera */