num2str fixes

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

diff --git a/lib/num2str.c b/lib/num2str.c
index e114cdf8ebea83db1d79725403475f977b7d7cc9..559cbeb590e4926b2d34f3b34cf6ac4cc0eadf10 100644 (file)
--- a/lib/num2str.c
+++ b/lib/num2str.c
@@ -10,8 +10,8 @@ char *num2str(unsigned long num, int maxlen, int base, int pow2)
        char postfix[] = { ' ', 'K', 'M', 'G', 'P', 'E' };
        unsigned int thousand[] = { 1000, 1024 };
        unsigned int modulo, decimals;
-       int post_index;
-       char tmp[32], fmt[8];
+       int post_index, carry = 0;
+       char tmp[32];
        char *buf;
 
        buf = malloc(128);
@@ -27,6 +27,7 @@ char *num2str(unsigned long num, int maxlen, int base, int pow2)
 
                modulo = num % thousand[!!pow2];
                num /= thousand[!!pow2];
+               carry = modulo >= thousand[!!pow2] / 2;
                post_index++;
        }
 
@@ -38,11 +39,20 @@ done:
 
        sprintf(tmp, "%lu", num);
        decimals = maxlen - strlen(tmp);
-       if (decimals <= 1)
+       if (decimals <= 1) {
+               if (carry)
+                       num++;
                goto done;
+       }
+
+       do {
+               sprintf(tmp, "%u", modulo);
+               if (strlen(tmp) <= decimals - 1)
+                       break;
+
+               modulo = (modulo + 9) / 10;
+       } while (1);
 
-       sprintf(fmt, "%%.%uu", decimals - 1);
-       sprintf(tmp, fmt, modulo);
-       sprintf(buf, "%lu.%s%c", num, tmp, postfix[post_index]);
+       sprintf(buf, "%lu.%u%c", num, modulo, postfix[post_index]);
        return buf;
 }