X-Git-Url: https://git.ozlabs.org/?a=blobdiff_plain;f=ccan%2Ftally%2Ftally.c;h=0d49319608d2ff6dc53edf9d62429e055c50f152;hb=05b39faed2c73b317f6a7f6f59ec0e8c69e5d5bf;hp=b3ac863ba68119aedc59973b72c1d3716bb35867;hpb=097857e6c09bf9696797fe08cd4241b8315f9c9a;p=ccan

diff --git a/ccan/tally/tally.c b/ccan/tally/tally.c
index b3ac863b..0d493196 100644
--- a/ccan/tally/tally.c
+++ b/ccan/tally/tally.c
@@ -1,4 +1,4 @@
-#include "config.h"
+/* Licensed under LGPLv3+ - see LICENSE file for details */
 #include <ccan/tally/tally.h>
 #include <ccan/build_assert/build_assert.h>
 #include <ccan/likely/likely.h>
@@ -7,6 +7,7 @@
 #include <string.h>
 #include <stdio.h>
 #include <assert.h>
+#include <stdlib.h>
 
 #define SIZET_BITS (sizeof(size_t)*CHAR_BIT)
 
@@ -27,8 +28,8 @@ struct tally *tally_new(unsigned buckets)
 	if (buckets == 0)
 		buckets = 1;
 
-	/* Check for overflow. */
-	if (buckets && SIZE_MAX / buckets < sizeof(tally->counts[0]))
+	/* Overly cautious check for overflow. */
+	if (sizeof(*tally) * buckets / sizeof(*tally) != buckets)
 		return NULL;
 	tally = malloc(sizeof(*tally) + sizeof(tally->counts[0])*(buckets-1));
 	if (tally) {
@@ -322,7 +323,7 @@ ssize_t tally_total(const struct tally *tally, ssize_t *overflow)
 	}
 
 	/* If result is negative, make sure we can represent it. */
-	if (tally->total[1] & (1 << (SIZET_BITS-1))) {
+	if (tally->total[1] & ((size_t)1 << (SIZET_BITS-1))) {
 		/* Must have only underflowed once, and must be able to
 		 * represent result at ssize_t. */
 		if ((~tally->total[1])+1 != 0
@@ -455,14 +456,17 @@ char *tally_histogram(const struct tally *tally,
 	}
 
 	for (i = 0; i < height; i++) {
-		unsigned covered = 1;
-		count = (double)tally->counts[i] / largest_bucket * (width-1)+1;
+		unsigned covered = 1, row;
 
-		if (i == 0)
+		/* People expect minimum at the bottom. */
+		row = height - i - 1;
+		count = (double)tally->counts[row] / largest_bucket * (width-1)+1;
+
+		if (row == 0)
 			covered = snprintf(p, width, "%zi", tally->min);
-		else if (i == height - 1)
+		else if (row == height - 1)
 			covered = snprintf(p, width, "%zi", tally->max);
-		else if (i == bucket_of(tally->min, tally->step_bits, 0))
+		else if (row == bucket_of(tally->min, tally->step_bits, 0))
 			*p = '+';
 		else
 			*p = '|';