]> git.ozlabs.org Git - ccan/blobdiff - ccan/tally/tally.c
tally: Adapt fls64 to Samba coding conventions
[ccan] / ccan / tally / tally.c
index 0d0190795557b60ccfe8d73138dfda2baf99477d..4e8876cc4aa5e2874fa83c1b341783e9811d0927 100644 (file)
@@ -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)
 
@@ -24,29 +25,36 @@ struct tally *tally_new(unsigned buckets)
        struct tally *tally;
 
        /* There is always 1 bucket. */
-       if (buckets == 0)
+       if (buckets == 0) {
                buckets = 1;
+       }
+
+       /* Overly cautious check for overflow. */
+       if (sizeof(*tally) * buckets / sizeof(*tally) != buckets) {
+               return NULL;
+       }
 
-       /* Check for overflow. */
-       if (buckets && SIZE_MAX / buckets < sizeof(tally->counts[0]))
+       tally = (struct tally *)malloc(
+               sizeof(*tally) + sizeof(tally->counts[0])*(buckets-1));
+       if (tally == NULL) {
                return NULL;
-       tally = malloc(sizeof(*tally) + sizeof(tally->counts[0])*(buckets-1));
-       if (tally) {
-               tally->max = ((size_t)1 << (SIZET_BITS - 1));
-               tally->min = ~tally->max;
-               tally->total[0] = tally->total[1] = 0;
-               tally->buckets = buckets;
-               tally->step_bits = 0;
-               memset(tally->counts, 0, sizeof(tally->counts[0])*buckets);
        }
+
+       tally->max = ((size_t)1 << (SIZET_BITS - 1));
+       tally->min = ~tally->max;
+       tally->total[0] = tally->total[1] = 0;
+       tally->buckets = buckets;
+       tally->step_bits = 0;
+       memset(tally->counts, 0, sizeof(tally->counts[0])*buckets);
        return tally;
 }
 
 static unsigned bucket_of(ssize_t min, unsigned step_bits, ssize_t val)
 {
        /* Don't over-shift. */
-       if (step_bits == SIZET_BITS)
+       if (step_bits == SIZET_BITS) {
                return 0;
+       }
        assert(step_bits < SIZET_BITS);
        return (size_t)(val - min) >> step_bits;
 }
@@ -55,8 +63,9 @@ static unsigned bucket_of(ssize_t min, unsigned step_bits, ssize_t val)
 static ssize_t bucket_min(ssize_t min, unsigned step_bits, unsigned b)
 {
        /* Don't over-shift. */
-       if (step_bits == SIZET_BITS)
+       if (step_bits == SIZET_BITS) {
                return min;
+       }
        assert(step_bits < SIZET_BITS);
        return min + ((ssize_t)b << step_bits);
 }
@@ -64,8 +73,9 @@ static ssize_t bucket_min(ssize_t min, unsigned step_bits, unsigned b)
 /* Does shifting by this many bits truncate the number? */
 static bool shift_overflows(size_t num, unsigned bits)
 {
-       if (bits == 0)
+       if (bits == 0) {
                return false;
+       }
 
        return ((num << bits) >> 1) != (num << (bits - 1));
 }
@@ -78,8 +88,9 @@ static void renormalize(struct tally *tally,
        unsigned int i, old_min;
 
        /* Uninitialized?  Don't do anything... */
-       if (tally->max < tally->min)
+       if (tally->max < tally->min) {
                goto update;
+       }
 
        /* If we don't have sufficient range, increase step bits until
         * buckets cover entire range of ssize_t anyway. */
@@ -127,15 +138,17 @@ void tally_add(struct tally *tally, ssize_t val)
                new_max = val;
                need_renormalize = true;
        }
-       if (need_renormalize)
+       if (need_renormalize) {
                renormalize(tally, new_min, new_max);
+       }
 
        /* 128-bit arithmetic!  If we didn't want exact mean, we could just
         * pull it out of counts. */
-       if (val > 0 && tally->total[0] + val < tally->total[0])
+       if (val > 0 && tally->total[0] + val < tally->total[0]) {
                tally->total[1]++;
-       else if (val < 0 && tally->total[0] + val > tally->total[0])
+       } else if (val < 0 && tally->total[0] + val > tally->total[0]) {
                tally->total[1]--;
+       }
        tally->total[0] += val;
        tally->counts[bucket_of(tally->min, tally->step_bits, val)]++;
 }
@@ -143,8 +156,9 @@ void tally_add(struct tally *tally, ssize_t val)
 size_t tally_num(const struct tally *tally)
 {
        size_t i, num = 0;
-       for (i = 0; i < tally->buckets; i++)
+       for (i = 0; i < tally->buckets; i++) {
                num += tally->counts[i];
+       }
        return num;
 }
 
@@ -169,8 +183,9 @@ static unsigned fls64(uint64_t val)
 #endif
        uint64_t r = 64;
 
-       if (!val)
+       if (!val) {
                return 0;
+       }
        if (!(val & 0xffffffff00000000ull)) {
                val <<= 32;
                r -= 32;
@@ -448,7 +463,7 @@ char *tally_histogram(const struct tally *tally,
                        largest_bucket = tally->counts[i];
        }
 
-       p = graph = malloc(height * (width + 1) + 1);
+       p = graph = (char *)malloc(height * (width + 1) + 1);
        if (!graph) {
                free(tmp);
                return NULL;