tally: implement tally_total()

[ccan] / ccan / tally / tally.h

diff --git a/ccan/tally/tally.h b/ccan/tally/tally.h
index 1f4b5d5f7576f89673a59ec78a45606ad9220691..b38cd70646f3b6205eb71e4ef07a01c2afec20cd 100644 (file)
--- a/ccan/tally/tally.h
+++ b/ccan/tally/tally.h
@@ -51,6 +51,17 @@ ssize_t tally_max(const struct tally *tally);
  */
 ssize_t tally_mean(const struct tally *tally);
 
+/**
+ * tally_total - the total value passed to tally_add.
+ * @tally: the tally structure.
+ * @overflow: the overflow value (or NULL).
+ *
+ * If your total can't overflow a ssize_t, you don't need @overflow.
+ * Otherwise, @overflow is the upper ssize_t, and the return value should
+ * be treated as the lower size_t (ie. the sign bit is in @overflow).
+ */
+ssize_t tally_total(const struct tally *tally, ssize_t *overflow);
+
 /**
  * tally_approx_median - the approximate median value passed to tally_add.
  * @tally: the tally structure.