Merge remote-tracking branch 'upstream/master'

1 files changed, 12 insertions, 0 deletions

diff --git a/src/cryptonote_core/difficulty.h b/src/cryptonote_core/difficulty.h
index d49c2f3b8..910f97035 100644
--- a/src/cryptonote_core/difficulty.h
+++ b/src/cryptonote_core/difficulty.h
@@ -39,6 +39,18 @@ namespace cryptonote
 {
     typedef std::uint64_t difficulty_type;
 
+    /**
+     * @brief checks if a hash fits the given difficulty
+     *
+     * The hash passes if (hash * difficulty) < 2^192.
+     * Phrased differently, if (hash * difficulty) fits without overflow into
+     * the least significant 192 bits of the 256 bit multiplication result.
+     *
+     * @param hash the hash to check
+     * @param difficulty the difficulty to check against
+     *
+     * @return true if valid, else false
+     */
     bool check_hash(const crypto::hash &hash, difficulty_type difficulty);
     difficulty_type next_difficulty(std::vector<std::uint64_t> timestamps, std::vector<difficulty_type> cumulative_difficulties, size_t target_seconds);
 }