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agl-alexglopez · Dec 18, 2024 · 57cf47b · 57cf47b
1 parent bc78762
commit 57cf47b
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/src/bitset.c b/src/bitset.c
@@ -174,6 +174,10 @@ on(size_t bit_i)
     return (ccc_bitblock_)1 << (bit_i % CCC_IMPL_BTST_BLOCK_BITS);
 }
 
+/* Returns a mask of all bits on in the final bit block that represent only
+   those bits which are in use according to the bit set capacity. The remaining
+   higher order bits in the last block will be set to 0 because they are not
+   used. If the capacity is zero a block with all bits on is returned. */
 static ccc_bitblock_
 last_on(struct ccc_bitset_ const *const btst)
 {