Add documentation of filter_get().

It's a public function that should be documented.

diff --git a/filter_common.c b/filter_common.c
index 099d056ef1514e2f606adf30d779308b58bead95..6fb9bd96ef8278b3e328198e24db78664a956542 100644 (file)
--- a/filter_common.c
+++ b/filter_common.c
@@ -25,6 +25,16 @@
 /** The array of supported filters. */
 static struct filter filters[NUM_SUPPORTED_FILTERS] = {FILTER_ARRAY};
 
+/**
+ * Obtain a reference to a filter structure.
+ *
+ * \param filter_num Between zero and NUM_SUPPORTED_FILTERS, inclusively.
+ *
+ * \return Pointer to the filter identified by the given filter number.
+ *
+ * It is a fatal error if the given number is out of range. In this case
+ * the function aborts.
+ */
 const struct filter *filter_get(int filter_num)
 {
        assert(filter_num >= 0);