/*-
 * Copyright 2012 Clifton Royston
 * Copyright 2013 John-Mark Gurney
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 */

#include <sys/param.h>
#include <inttypes.h>
#include <libutil.h>
#include <limits.h>
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#define MAX_STR_FLAGS_RESULT    80
#define MAX_INT_STR_DIGITS      12

static const int64_t halfExabyte = (int64_t)500*1000*1000*1000*1000*1000L;

static struct {
        int retval;
        const char *res;
        int64_t num;
        int flags;
        int scale;
        size_t buflen;
} test_args[] = {
        /* tests 0-13 test 1000 suffixes */
        { 2, "0 ", (int64_t)0L, HN_DIVISOR_1000, HN_AUTOSCALE, 4 },
        { 3, "1 k", (int64_t)500L, HN_DIVISOR_1000, HN_AUTOSCALE, 4 },
        { 3, "1 M", (int64_t)500*1000L, HN_DIVISOR_1000, HN_AUTOSCALE, 4 },
        { 3, "1 G", (int64_t)500*1000*1000L, HN_DIVISOR_1000, HN_AUTOSCALE, 4 },
        { 3, "1 T", (int64_t)500*1000*1000*1000L, HN_DIVISOR_1000, HN_AUTOSCALE, 4 },
        { 3, "1 P", (int64_t)500*1000*1000*1000*1000L, HN_DIVISOR_1000, HN_AUTOSCALE, 4 },
        { 3, "1 E", (int64_t)500*1000*1000*1000*1000*1000L, HN_DIVISOR_1000, HN_AUTOSCALE, 4 },
        { 2, "1 ", (int64_t)1L, HN_DIVISOR_1000, HN_AUTOSCALE, 4 },
        { 3, "2 k", (int64_t)1500L, HN_DIVISOR_1000, HN_AUTOSCALE, 4 },
        { 3, "2 M", (int64_t)1500*1000L, HN_DIVISOR_1000, HN_AUTOSCALE, 4 },
        { 3, "2 G", (int64_t)1500*1000*1000L, HN_DIVISOR_1000, HN_AUTOSCALE, 4 },
        { 3, "2 T", (int64_t)1500*1000*1000*1000L, HN_DIVISOR_1000, HN_AUTOSCALE, 4 },
        { 3, "2 P", (int64_t)1500*1000*1000*1000*1000L, HN_DIVISOR_1000, HN_AUTOSCALE, 4 },
        { 3, "2 E", (int64_t)1500*1000*1000*1000*1000*1000L, HN_DIVISOR_1000, HN_AUTOSCALE, 4 },

        /* tests 14-27 test 1024 suffixes */
        { 2, "0 ", (int64_t)0L, 0, HN_AUTOSCALE, 4 },
        { 3, "1 K", (int64_t)512L, 0, HN_AUTOSCALE, 4 },
        { 3, "1 M", (int64_t)512*1024L, 0, HN_AUTOSCALE, 4 },
        { 3, "1 G", (int64_t)512*1024*1024L, 0, HN_AUTOSCALE, 4 },
        { 3, "1 T", (int64_t)512*1024*1024*1024L, 0, HN_AUTOSCALE, 4 },
        { 3, "1 P", (int64_t)512*1024*1024*1024*1024L, 0, HN_AUTOSCALE, 4 },
        { 3, "1 E", (int64_t)512*1024*1024*1024*1024*1024L, 0, HN_AUTOSCALE, 4 },
        { 2, "1 ", (int64_t)1L, 0, HN_AUTOSCALE, 4 },
        { 3, "2 K", (int64_t)1536L, 0, HN_AUTOSCALE, 4 },
        { 3, "2 M", (int64_t)1536*1024L, 0, HN_AUTOSCALE, 4 },
        { 3, "2 G", (int64_t)1536*1024*1024L, 0, HN_AUTOSCALE, 4 },
        { 3, "2 T", (int64_t)1536*1024*1024*1024L, 0, HN_AUTOSCALE, 4 },
        { 3, "2 P", (int64_t)1536*1024*1024*1024*1024L, 0, HN_AUTOSCALE, 4 },
        { 3, "2 E", (int64_t)1536*1024*1024*1024*1024*1024L, 0, HN_AUTOSCALE, 4 },

        /* tests 28-37 test rounding */
        { 3, "0 M", (int64_t)500*1000L-1, HN_DIVISOR_1000, HN_AUTOSCALE, 4 },
        { 3, "1 M", (int64_t)500*1000L, HN_DIVISOR_1000, HN_AUTOSCALE, 4 },
        { 3, "1 M", (int64_t)1000*1000L + 500*1000L-1, HN_DIVISOR_1000, HN_AUTOSCALE, 4 },
        { 3, "2 M", (int64_t)1000*1000L + 500*1000L, HN_DIVISOR_1000, HN_AUTOSCALE, 4 },
        { 3, "0 K", (int64_t)512L-1, 0, HN_AUTOSCALE, 4 },
        { 3, "1 K", (int64_t)512L, 0, HN_AUTOSCALE, 4 },
        { 3, "0 M", (int64_t)512*1024L-1, 0, HN_AUTOSCALE, 4 },
        { 3, "1 M", (int64_t)512*1024L, 0, HN_AUTOSCALE, 4 },
        { 3, "1 M", (int64_t)1024*1024L + 512*1024L-1, 0, HN_AUTOSCALE, 4 },
        { 3, "2 M", (int64_t)1024*1024L + 512*1024L, 0, HN_AUTOSCALE, 4 },

        /* tests 38-61 test specific scale factors with 1000 divisor */
        { 3, "0 k", (int64_t)0L, HN_DIVISOR_1000, 1, 4 },
        { 3, "1 k", (int64_t)500L, HN_DIVISOR_1000, 1, 4 },
        { 3, "0 M", (int64_t)500L, HN_DIVISOR_1000, 2, 4 },
        { 3, "1 M", (int64_t)500*1000L, HN_DIVISOR_1000, 2, 4 },
        { 3, "0 G", (int64_t)500*1000L, HN_DIVISOR_1000, 3, 4 },
        { 3, "1 G", (int64_t)500*1000*1000L, HN_DIVISOR_1000, 3, 4 },
        { 3, "0 T", (int64_t)500*1000*1000L, HN_DIVISOR_1000, 4, 4 },
        { 3, "1 T", (int64_t)500*1000*1000*1000L, HN_DIVISOR_1000, 4, 4 },
        { 3, "0 P", (int64_t)500*1000*1000*1000L, HN_DIVISOR_1000, 5, 4 },
        { 3, "1 P", (int64_t)500*1000*1000*1000*1000L, HN_DIVISOR_1000, 5, 4 },
        { 3, "0 E", (int64_t)500*1000*1000*1000*1000L, HN_DIVISOR_1000, 6, 4 },
        { 3, "1 E", (int64_t)500*1000*1000*1000*1000*1000L, HN_DIVISOR_1000, 6, 4 },
        { 3, "0 k", (int64_t)1L, HN_DIVISOR_1000, 1, 4 },
        { 3, "2 k", (int64_t)1500L, HN_DIVISOR_1000, 1, 4 },
        { 3, "0 M", (int64_t)1500L, HN_DIVISOR_1000, 2, 4 },
        { 3, "2 M", (int64_t)1500*1000L, HN_DIVISOR_1000, 2, 4 },
        { 3, "0 G", (int64_t)1500*1000L, HN_DIVISOR_1000, 3, 4 },
        { 3, "2 G", (int64_t)1500*1000*1000L, HN_DIVISOR_1000, 3, 4 },
        { 3, "0 T", (int64_t)1500*1000*1000L, HN_DIVISOR_1000, 4, 4 },
        { 3, "2 T", (int64_t)1500*1000*1000*1000L, HN_DIVISOR_1000, 4, 4 },
        { 3, "0 P", (int64_t)1500*1000*1000*1000L, HN_DIVISOR_1000, 5, 4 },
        { 3, "2 P", (int64_t)1500*1000*1000*1000*1000L, HN_DIVISOR_1000, 5, 4 },
        { 3, "0 E", (int64_t)1500*1000*1000*1000*1000L, HN_DIVISOR_1000, 6, 4 },
        { 3, "2 E", (int64_t)1500*1000*1000*1000*1000*1000L, HN_DIVISOR_1000, 6, 4 },

        /* tests 62-85 test specific scale factors with 1024 divisor */
        { 3, "0 K", (int64_t)0L, 0, 1, 4 },
        { 3, "1 K", (int64_t)512L, 0, 1, 4 },
        { 3, "0 M", (int64_t)512L, 0, 2, 4 },
        { 3, "1 M", (int64_t)512*1024L, 0, 2, 4 },
        { 3, "0 G", (int64_t)512*1024L, 0, 3, 4 },
        { 3, "1 G", (int64_t)512*1024*1024L, 0, 3, 4 },
        { 3, "0 T", (int64_t)512*1024*1024L, 0, 4, 4 },
        { 3, "1 T", (int64_t)512*1024*1024*1024L, 0, 4, 4 },
        { 3, "0 P", (int64_t)512*1024*1024*1024L, 0, 5, 4 },
        { 3, "1 P", (int64_t)512*1024*1024*1024*1024L, 0, 5, 4 },
        { 3, "0 E", (int64_t)512*1024*1024*1024*1024L, 0, 6, 4 },
        { 3, "1 E", (int64_t)512*1024*1024*1024*1024*1024L, 0, 6, 4 },
        { 3, "0 K", (int64_t)1L, 0, 1, 4 },
        { 3, "2 K", (int64_t)1536L, 0, 1, 4 },
        { 3, "0 M", (int64_t)1536L, 0, 2, 4 },
        { 3, "2 M", (int64_t)1536*1024L, 0, 2, 4 },
        { 3, "0 G", (int64_t)1536*1024L, 0, 3, 4 },
        { 3, "2 G", (int64_t)1536*1024*1024L, 0, 3, 4 },
        { 3, "0 T", (int64_t)1536*1024*1024L, 0, 4, 4 },
        { 3, "2 T", (int64_t)1536*1024*1024*1024L, 0, 4, 4 },
        { 3, "0 P", (int64_t)1536*1024*1024*1024L, 0, 5, 4 },
        { 3, "2 P", (int64_t)1536*1024*1024*1024*1024L, 0, 5, 4 },
        { 3, "0 E", (int64_t)1536*1024*1024*1024*1024L, 0, 6, 4 },
        { 3, "2 E", (int64_t)1536*1024*1024*1024*1024*1024L, 0, 6, 4 },

        /* tests 86-99 test invalid specific scale values of < 0 or >= 7 with
        and without HN_DIVISOR_1000 set */
        /*  all should return errors with new code; with old, the latter 3
        are instead processed as if having AUTOSCALE and/or GETSCALE set */
        { -1, "", (int64_t)1L, 0, 7, 4 },
        { -1, "", (int64_t)1L, HN_DIVISOR_1000, 7, 4 },
        { -1, "", (int64_t)1L, 0, 1000, 4 },
        { -1, "", (int64_t)1L, HN_DIVISOR_1000, 1000, 4 },
        { -1, "", (int64_t)0L, 0, 1000*1000, 4 },
        { -1, "", (int64_t)0L, HN_DIVISOR_1000, 1000*1000, 4 },
        { -1, "", (int64_t)0L, 0, INT_MAX, 4 },
        { -1, "", (int64_t)0L, HN_DIVISOR_1000, INT_MAX, 4 },

        /* Negative scale values are not handled well
         by the existing library routine - should report as error */
        /*  all should return errors with new code, fail assertion with old */

        { -1, "", (int64_t)1L, 0, -1, 4 },
        { -1, "", (int64_t)1L, HN_DIVISOR_1000, -1, 4 },
        { -1, "", (int64_t)1L, 0, -1000, 4 },
        { -1, "", (int64_t)1L, HN_DIVISOR_1000, -1000, 4 },

        /* __INT_MIN doesn't print properly, skipped. */

        { -1, "", (int64_t)1L, 0, -__INT_MAX, 4 },
        { -1, "", (int64_t)1L, HN_DIVISOR_1000, -__INT_MAX, 4 },


        /* tests for scale == 0, without autoscale */
        /* tests 100-114 test scale 0 with 1000 divisor - print first N digits */
        { 2, "0 ", (int64_t)0L, HN_DIVISOR_1000, 0, 4 },
        { 2, "1 ", (int64_t)1L, HN_DIVISOR_1000, 0, 4 },
        { 3, "10 ", (int64_t)10L, HN_DIVISOR_1000, 0, 4 },
        { 3, "0 M", (int64_t)150L, HN_DIVISOR_1000, HN_NOSPACE, 4 },
        { 3, "0 M", (int64_t)500L, HN_DIVISOR_1000, HN_NOSPACE, 4 },
        { 3, "0 M", (int64_t)999L, HN_DIVISOR_1000, HN_NOSPACE, 4 },
        { 4, "150", (int64_t)150L, HN_DIVISOR_1000, 0, 4 },
        { 4, "500", (int64_t)500L, HN_DIVISOR_1000, 0, 4 },
        { 4, "999", (int64_t)999L, HN_DIVISOR_1000, 0, 4 },
        { 5, "100", (int64_t)1000L, HN_DIVISOR_1000, 0, 4 },
        { 5, "150", (int64_t)1500L, HN_DIVISOR_1000, 0, 4 },
        { 7, "500", (int64_t)500*1000L, HN_DIVISOR_1000, 0, 4 },
        { 8, "150", (int64_t)1500*1000L, HN_DIVISOR_1000, 0, 4 },
        { 10, "500", (int64_t)500*1000*1000L, HN_DIVISOR_1000, 0, 4 },
        { 11, "150", (int64_t)1500*1000*1000L, HN_DIVISOR_1000, 0, 4 },

        /* tests 115-126 test scale 0 with 1024 divisor - print first N digits */
        { 2, "0 ", (int64_t)0L, 0, 0, 4 },
        { 2, "1 ", (int64_t)1L, 0, 0, 4 },
        { 3, "10 ", (int64_t)10L, 0, 0, 4 },
        { 4, "150", (int64_t)150L, 0, 0, 4 },
        { 4, "500", (int64_t)500L, 0, 0, 4 },
        { 4, "999", (int64_t)999L, 0, 0, 4 },
        { 5, "100", (int64_t)1000L, 0, 0, 4 },
        { 5, "150", (int64_t)1500L, 0, 0, 4 },
        { 7, "500", (int64_t)500*1000L, 0, 0, 4 },
        { 8, "150", (int64_t)1500*1000L, 0, 0, 4 },
        { 10, "500", (int64_t)500*1000*1000L, 0, 0, 4 },
        { 11, "150", (int64_t)1500*1000*1000L, 0, 0, 4 },

        /* Test case for rounding of edge numbers around 999.5+, see PR224498.
         * Require buflen >= 5 */
        { 4, "1.0M", (int64_t)1023500, HN_DECIMAL|HN_B|HN_NOSPACE, HN_AUTOSCALE, 5 },

        /* Test boundary cases for very large positive/negative number formatting */
        /* Explicit scale, divisor 1024 */

        /* Requires buflen >= 6 */
        { 3, "8 E",   INT64_MAX, 0, 6, 6 },
        { 4, "-8 E", -INT64_MAX, 0, 6, 6 },
        { 3, "0 E", (int64_t)92*1024*1024*1024*1024*1024L, 0, 6, 6 },
        { 3, "0 E", -(int64_t)92*1024*1024*1024*1024*1024L, 0, 6, 6 },
        { 3, "0 E", (int64_t)82*1024*1024*1024*1024*1024L, 0, 6, 6 },
        { 3, "0 E", -(int64_t)82*1024*1024*1024*1024*1024L, 0, 6, 6 },
        { 3, "0 E", (int64_t)81*1024*1024*1024*1024*1024L, 0, 6, 6 },
        { 3, "0 E", -(int64_t)81*1024*1024*1024*1024*1024L, 0, 6, 6 },
        { 4, "92 P", (int64_t)92*1024*1024*1024*1024*1024L, 0, 5, 6 },
        { 5, "-92 P", -(int64_t)92*1024*1024*1024*1024*1024L, 0, 5, 6 },
        { 4, "82 P", (int64_t)82*1024*1024*1024*1024*1024L, 0, 5, 6 },
        { 5, "-82 P", -(int64_t)82*1024*1024*1024*1024*1024L, 0, 5, 6 },
        { 4, "81 P", (int64_t)81*1024*1024*1024*1024*1024L, 0, 5, 6 },
        { 5, "-81 P", -(int64_t)81*1024*1024*1024*1024*1024L, 0, 5, 6 },

        /* Explicit scale, divisor 1000 */
        { 3, "9 E",   INT64_MAX, HN_DIVISOR_1000, 6, 6 },
        { 4, "-9 E", -INT64_MAX, HN_DIVISOR_1000,  6, 6 },
        { 3, "0 E", (int64_t)82*1024*1024*1024*1024*1024L, HN_DIVISOR_1000,  6, 6 },
        { 3, "0 E", -(int64_t)82*1024*1024*1024*1024*1024L, HN_DIVISOR_1000,  6, 6 },
        { 3, "0 E", (int64_t)82*1024*1024*1024*1024*1024L, HN_DIVISOR_1000,  6, 6 },
        { 3, "0 E", -(int64_t)82*1024*1024*1024*1024*1024L, HN_DIVISOR_1000,  6, 6 },
        { 4, "92 P", (int64_t)82*1024*1024*1024*1024*1024L, HN_DIVISOR_1000,  5, 6 },
        { 5, "-92 P", -(int64_t)82*1024*1024*1024*1024*1024L, HN_DIVISOR_1000,  5, 6 },
        { 4, "91 P", (int64_t)81*1024*1024*1024*1024*1024L, HN_DIVISOR_1000,  5, 6 },
        { 5, "-91 P", -(int64_t)81*1024*1024*1024*1024*1024L, HN_DIVISOR_1000,  5, 6 },

        /* Autoscale, divisor 1024 */
        { 3, "8 E",   INT64_MAX, 0, HN_AUTOSCALE, 6 },
        { 4, "-8 E", -INT64_MAX, 0, HN_AUTOSCALE, 6 },
        { 4, "92 P", (int64_t)92*1024*1024*1024*1024*1024L, 0, HN_AUTOSCALE, 6 },
        { 5, "-92 P", -(int64_t)92*1024*1024*1024*1024*1024L, 0, HN_AUTOSCALE, 6 },
        { 4, "82 P", (int64_t)82*1024*1024*1024*1024*1024L, 0, HN_AUTOSCALE, 6 },
        { 5, "-82 P", -(int64_t)82*1024*1024*1024*1024*1024L, 0, HN_AUTOSCALE, 6 },
        { 4, "81 P", (int64_t)81*1024*1024*1024*1024*1024L, 0, HN_AUTOSCALE, 6 },
        { 5, "-81 P", -(int64_t)81*1024*1024*1024*1024*1024L, 0, HN_AUTOSCALE, 6 },
        /* Autoscale, divisor 1000 */
        { 3, "9 E",   INT64_MAX, HN_DIVISOR_1000, HN_AUTOSCALE, 6 },
        { 4, "-9 E", -INT64_MAX, HN_DIVISOR_1000, HN_AUTOSCALE, 6 },
        { 4, "92 P", (int64_t)82*1024*1024*1024*1024*1024L, HN_DIVISOR_1000, HN_AUTOSCALE, 6 },
        { 5, "-92 P", -(int64_t)82*1024*1024*1024*1024*1024L, HN_DIVISOR_1000, HN_AUTOSCALE, 6 },
        { 4, "91 P", (int64_t)81*1024*1024*1024*1024*1024L, HN_DIVISOR_1000, HN_AUTOSCALE, 6 },
        { 5, "-91 P", -(int64_t)81*1024*1024*1024*1024*1024L, HN_DIVISOR_1000, HN_AUTOSCALE, 6 },

        /* 0 scale, divisor 1024 */
        { 12, "skdj",  INT64_MAX, 0, 0, 6 },
        { 21, "-9223", -INT64_MAX, 0, 0, 6 },
        { 19, "10358", (int64_t)92*1024*1024*1024*1024*1024L, 0, 0, 6 },
        { 20, "-1035", -(int64_t)92*1024*1024*1024*1024*1024L, 0, 0, 6 },
        { 18, "92323", (int64_t)82*1024*1024*1024*1024*1024L, 0, 0, 6 },
        { 19, "-9232", -(int64_t)82*1024*1024*1024*1024*1024L, 0, 0, 6 },
        { 18, "91197", (int64_t)81*1024*1024*1024*1024*1024L, 0, 0, 6 },
        { 19, "-9119", -(int64_t)81*1024*1024*1024*1024*1024L, 0, 0, 6 },

        /* 0 scale, divisor 1000 */
        /* XXX - why does this fail? */
        { -1, "", INT64_MAX, HN_DIVISOR_1000, 0, 6 },
        { 21, "-9223", -INT64_MAX, HN_DIVISOR_1000,  0, 6 },
        { 19, "10358", (int64_t)92*1024*1024*1024*1024*1024L, HN_DIVISOR_1000,  0, 6 },
        { 20, "-1035", -(int64_t)92*1024*1024*1024*1024*1024L, HN_DIVISOR_1000,  0, 6 },
        { 18, "92323", (int64_t)82*1024*1024*1024*1024*1024L, HN_DIVISOR_1000,  0, 6 },
        { 19, "-9232", -(int64_t)82*1024*1024*1024*1024*1024L, HN_DIVISOR_1000,  0, 6 },
        /* Expected to pass */
        { 18, "91197", (int64_t)81*1024*1024*1024*1024*1024L, HN_DIVISOR_1000,  0, 6 },
        { 19, "-9119", -(int64_t)81*1024*1024*1024*1024*1024L, HN_DIVISOR_1000,  0, 6 },



        /* Need to implement tests for GETSCALE */
/*      { ?, "", (int64_t)0L, HN_DIVISOR_1000, HN_GETSCALE, 6 },
        ...
*/
        /* Tests for HN_DECIMAL */
        /* Positive, Autoscale */
        { 5, "500 k", (int64_t)500*1000L, HN_DECIMAL|HN_DIVISOR_1000, HN_AUTOSCALE, 6 },
        { 5, "994 k", (int64_t)994*1000L, HN_DECIMAL|HN_DIVISOR_1000, HN_AUTOSCALE, 6 },
        { 5, "995 k", (int64_t)995*1000L, HN_DECIMAL|HN_DIVISOR_1000, HN_AUTOSCALE, 6 },
        { 5, "999 k", (int64_t)999*1000L, HN_DECIMAL|HN_DIVISOR_1000, HN_AUTOSCALE, 6 },
        { 5, "1.0 M", (int64_t)1000*1000L, HN_DECIMAL|HN_DIVISOR_1000, HN_AUTOSCALE, 6 },
        { 5, "1.5 M", (int64_t)1500*1000L, HN_DECIMAL|HN_DIVISOR_1000, HN_AUTOSCALE, 6 },
        { 5, "1.9 M", (int64_t)1949*1000L, HN_DECIMAL|HN_DIVISOR_1000, HN_AUTOSCALE, 6 },
        { 5, "2.0 M", (int64_t)1950*1000L, HN_DECIMAL|HN_DIVISOR_1000, HN_AUTOSCALE, 6 },
        { 5, "9.9 M", (int64_t)9949*1000L, HN_DECIMAL|HN_DIVISOR_1000, HN_AUTOSCALE, 6 },
        { 4, "10 M", (int64_t)9950*1000L, HN_DECIMAL|HN_DIVISOR_1000, HN_AUTOSCALE, 6 },
        { 5, "500 M", (int64_t)500*1000*1000L, HN_DECIMAL|HN_DIVISOR_1000, HN_AUTOSCALE, 6 },
        { 5, "994 M", (int64_t)994*1000*1000L, HN_DECIMAL|HN_DIVISOR_1000, HN_AUTOSCALE, 6 },
        { 5, "995 M", (int64_t)995*1000*1000L, HN_DECIMAL|HN_DIVISOR_1000, HN_AUTOSCALE, 6 },
        { 5, "999 M", (int64_t)999*1000*1000L, HN_DECIMAL|HN_DIVISOR_1000, HN_AUTOSCALE, 6 },

        { 5, "500 K", (int64_t)500*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 5, "994 K", (int64_t)994*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 5, "995 K", (int64_t)995*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 5, "999 K", (int64_t)999*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 5, "1.0 M", (int64_t)1000*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 5, "1.0 M", (int64_t)1018*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 5, "1.0 M", (int64_t)1019*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 5, "1.5 M", (int64_t)1536*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 5, "1.9 M", (int64_t)1996*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 5, "2.0 M", (int64_t)1997*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 5, "2.0 M", (int64_t)2047*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 5, "2.0 M", (int64_t)2048*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 5, "2.0 M", (int64_t)2099*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 5, "2.1 M", (int64_t)2100*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 5, "9.9 M", (int64_t)10188*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },
        /* XXX - shouldn't the following two be "10. M"? */
        { 4, "10 M", (int64_t)10189*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 4, "10 M", (int64_t)10240*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 5, "500 M", (int64_t)500*1024*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 5, "994 M", (int64_t)994*1024*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 5, "995 M", (int64_t)995*1024*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 5, "999 M", (int64_t)999*1024*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 5, "1.0 G", (int64_t)1000*1024*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 5, "1.0 G", (int64_t)1023*1024*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },

        /* Negative, Autoscale - should pass */
        { 6, "-1.5 ", -(int64_t)1500*1000L, HN_DECIMAL|HN_DIVISOR_1000, HN_AUTOSCALE, 6 },
        { 6, "-1.9 ", -(int64_t)1949*1000L, HN_DECIMAL|HN_DIVISOR_1000, HN_AUTOSCALE, 6 },
        { 6, "-9.9 ", -(int64_t)9949*1000L, HN_DECIMAL|HN_DIVISOR_1000, HN_AUTOSCALE, 6 },

        { 6, "-1.5 ", -(int64_t)1536*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 6, "-1.9 ", -(int64_t)1949*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 6, "-9.7 ", -(int64_t)9949*1024L, HN_DECIMAL, HN_AUTOSCALE, 6 },

        /* Positive/negative, at maximum scale */
        { 5, "500 P", (int64_t)500*1000*1000*1000*1000*1000L, HN_DIVISOR_1000, HN_AUTOSCALE, 6 },
        { 5, "1.9 E", (int64_t)1949*1000*1000*1000*1000*1000L, HN_DIVISOR_1000, HN_AUTOSCALE, 6 },
        { 5, "8.9 E", (int64_t)8949*1000*1000*1000*1000*1000L, HN_DIVISOR_1000, HN_AUTOSCALE, 6 },
        { 5, "9.2 E", INT64_MAX, HN_DECIMAL|HN_DIVISOR_1000, HN_AUTOSCALE, 6 },
        /* Negatives work with latest rev only: */
        { 6, "-9.2 ", -INT64_MAX, HN_DECIMAL|HN_DIVISOR_1000, HN_AUTOSCALE, 6 },
        { 6, "-8.9 ", -(int64_t)8949*1000*1000*1000*1000*1000L, HN_DECIMAL|HN_DIVISOR_1000, HN_AUTOSCALE, 6 },

        { 5, "8.0 E",   INT64_MAX, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 5, "7.9 E",   INT64_MAX-(int64_t)100*1024*1024*1024*1024*1024LL, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 6, "-8.0 ", -INT64_MAX, HN_DECIMAL, HN_AUTOSCALE, 6 },
        { 6, "-7.9 ",   -INT64_MAX+(int64_t)100*1024*1024*1024*1024*1024LL, HN_DECIMAL, HN_AUTOSCALE, 6 },

        /* Positive, Fixed scales */
        { 5, "500 k", (int64_t)500*1000L, HN_DECIMAL|HN_DIVISOR_1000, 1, 6 },
        { 5, "0.5 M", (int64_t)500*1000L, HN_DECIMAL|HN_DIVISOR_1000, 2, 6 },
        { 5, "949 k", (int64_t)949*1000L, HN_DECIMAL|HN_DIVISOR_1000, 1, 6 },
        { 5, "0.9 M", (int64_t)949*1000L, HN_DECIMAL|HN_DIVISOR_1000, 2, 6 },
        { 5, "950 k", (int64_t)950*1000L, HN_DECIMAL|HN_DIVISOR_1000, 1, 6 },
        { 5, "1.0 M", (int64_t)950*1000L, HN_DECIMAL|HN_DIVISOR_1000, 2, 6 },
        { 5, "999 k", (int64_t)999*1000L, HN_DECIMAL|HN_DIVISOR_1000, 1, 6 },
        { 5, "1.0 M", (int64_t)999*1000L, HN_DECIMAL|HN_DIVISOR_1000, 2, 6 },
        { 5, "1.5 M", (int64_t)1500*1000L, HN_DECIMAL|HN_DIVISOR_1000, 2, 6 },
        { 5, "1.9 M", (int64_t)1949*1000L, HN_DECIMAL|HN_DIVISOR_1000, 2, 6 },
        { 5, "2.0 M", (int64_t)1950*1000L, HN_DECIMAL|HN_DIVISOR_1000, 2, 6 },
        { 5, "9.9 M", (int64_t)9949*1000L, HN_DECIMAL|HN_DIVISOR_1000, 2, 6 },
        { 4, "10 M", (int64_t)9950*1000L, HN_DECIMAL|HN_DIVISOR_1000, 2, 6 },
        { 5, "500 M", (int64_t)500*1000*1000L, HN_DECIMAL|HN_DIVISOR_1000, 2, 6 },
        { 5, "0.5 G", (int64_t)500*1000*1000L, HN_DECIMAL|HN_DIVISOR_1000, 3, 6 },
        { 5, "999 M", (int64_t)999*1000*1000L, HN_DECIMAL|HN_DIVISOR_1000, 2, 6 },
        { 5, "1.0 G", (int64_t)999*1000*1000L, HN_DECIMAL|HN_DIVISOR_1000, 3, 6 },
        /* Positive/negative, at maximum scale */
        { 5, "500 P", (int64_t)500*1000*1000*1000*1000*1000L, HN_DIVISOR_1000, 5, 6 },
        { 5, "1.0 E", (int64_t)500*1000*1000*1000*1000*1000L, HN_DIVISOR_1000, 6, 6 },
        { 5, "1.9 E", (int64_t)1949*1000*1000*1000*1000*1000L, HN_DIVISOR_1000, 6, 6 },
        { 5, "8.9 E", (int64_t)8949*1000*1000*1000*1000*1000L, HN_DIVISOR_1000, 6, 6 },
        { 5, "9.2 E", INT64_MAX, HN_DECIMAL|HN_DIVISOR_1000, 6, 6 },

        /* HN_DECIMAL + binary + fixed scale cases not completed */
        { 5, "512 K", (int64_t)512*1024L, HN_DECIMAL, 1, 6 },
        { 5, "0.5 M", (int64_t)512*1024L, HN_DECIMAL, 2, 6 },

        /* Negative, Fixed scales */
        /* Not yet added, but should work with latest rev */

};


/* Command line options usage */
static void
usage(char * progname) {
        printf("%s: tests libutil humanize_number function\n", progname);
        printf("Usage: %s [-nE] [-l num] [-v]\n\n", progname);
        printf("Options:\n");
        printf("\t-l num\tSet max length for result; buflen = num + 1\n");
        printf("\t\t  (NOTE: does not change expected result strings.)\n");
        printf("\t-n\tInclude negative scale tests, which cause older libutil\n");
        printf("\t\t  version of function to coredump with assertion failure\n");
        printf("\t-E\tInclude numbers > 1/2 Exa[byte] which currently fail\n");
        printf("\t-v\tVerbose - always print summary results\n");
        printf("\t-h, -?\tShow options\n");
}

/* Parse command line options */
static void
read_options(int argc, char * const argv[], size_t *bufLength,
    int *includeNegativeScale, int *includeExabytes, int *verbose) {
        int ch;
        size_t temp;

        while ((ch = getopt(argc, argv, "nEh?vl:")) != -1) {
                switch (ch) {
                        default:
                                usage(argv[0]);
                                exit(1);
                                break;  /* UNREACHABLE */
                        case 'h' :
                        case '?' :
                                usage(argv[0]);
                                exit(0);
                                break;  /* UNREACHABLE */
                        case 'l' :
                                sscanf(optarg, "%zu", &temp);
                                *bufLength = temp + 1;
                                break;
                        case 'n' :
                                *includeNegativeScale = 1;
                                break;
                        case 'E' :
                                *includeExabytes = 1;
                                break;
                        case 'v' :
                                *verbose = 1;
                                break;
                }
        }
}

static struct {
        int value;
        const char *name;
 } flags[] = {
        { HN_AUTOSCALE, "HN_AUTOSCALE" },
        { HN_GETSCALE, "HN_GETSCALE" },
        { HN_DIVISOR_1000, "HN_DIVISOR_1000" },
        { HN_B, "HN_B" },
        { HN_DECIMAL, "HN_DECIMAL" },
};

static const char *separator = "|";

/* Format flags parameter for meaningful display */
static char *
str_flags(int hn_flags, char *noFlags) {
        size_t i;
        char * result;

        result = malloc(MAX_STR_FLAGS_RESULT);
        result[0] = '\0';

        for (i = 0; i < sizeof flags / sizeof *flags; i++) {
                if (hn_flags & flags[i].value) {
                        if (*result != 0)
                                strlcat(result, separator,
                                    MAX_STR_FLAGS_RESULT);
                        strlcat(result, flags[i].name, MAX_STR_FLAGS_RESULT);
                }
        }

        if (strlen(result) == 0)
                strlcat(result, noFlags, MAX_STR_FLAGS_RESULT);
        return result;
}


/* Format scale parameter for meaningful display */
static char *
str_scale(int scale) {
        char *result;

        if (scale == HN_AUTOSCALE || scale == HN_GETSCALE)
                return str_flags(scale, "");

        result = malloc(MAX_INT_STR_DIGITS);
        result[0] = '\0';
        snprintf(result, MAX_INT_STR_DIGITS, "%d", scale);
        return result;
}

static void
testskipped(size_t i)
{

        printf("ok %zu # skip - not turned on\n", i);
}

int
main(int argc, char * const argv[])
{
        char *buf;
        char *flag_str, *scale_str;
        size_t blen, buflen, errcnt, i, skipped, tested;
        int r;
        int includeNegScale;
        int includeExabyteTests;
        int verbose;

        buf = NULL;
        buflen = 0;
        includeNegScale = 0;
        includeExabyteTests = 0;
        verbose = 0;

        read_options(argc, argv, &buflen, &includeNegScale,
            &includeExabyteTests, &verbose);

        errcnt = 0;
        tested = 0;
        skipped = 0;

        if (buflen != 4)
                printf("Warning: buffer size %zu != 4, expect some results to differ.\n", buflen);

        printf("1..%zu\n", nitems(test_args));
        for (i = 0; i < nitems(test_args); i++) {
                blen = (buflen > 0) ? buflen : test_args[i].buflen;
                buf = realloc(buf, blen);

                if (test_args[i].scale < 0 && ! includeNegScale) {
                        skipped++;
                        testskipped(i + 1);
                        continue;
                }
                if (test_args[i].num >= halfExabyte && ! includeExabyteTests) {
                        skipped++;
                        testskipped(i + 1);
                        continue;
                }

                r = humanize_number(buf, blen, test_args[i].num, "",
                    test_args[i].scale, test_args[i].flags);
                flag_str = str_flags(test_args[i].flags, "[no flags]");
                scale_str = str_scale(test_args[i].scale);

                if (r != test_args[i].retval) {
                        if (verbose)
                                printf("wrong return value on index %zu, "
                                    "buflen: %zu, got: %d + \"%s\", "
                                    "expected %d + \"%s\"; num = %jd, "
                                    "scale = %s, flags= %s.\n",
                                    i, blen, r, buf, test_args[i].retval,
                                    test_args[i].res,
                                    (intmax_t)test_args[i].num,
                                    scale_str, flag_str);
                        else
                                printf("not ok %zu # return %d != %d\n",
                                    i + 1, r, test_args[i].retval);
                        errcnt++;
                } else if (strcmp(buf, test_args[i].res) != 0) {
                        if (verbose)
                                printf("result mismatch on index %zu, got: "
                                    "\"%s\", expected \"%s\"; num = %jd, "
                                    "buflen: %zu, scale = %s, flags= %s.\n",
                                    i, buf, test_args[i].res,
                                    (intmax_t)test_args[i].num,
                                    blen, scale_str, flag_str);
                        else
                                printf("not ok %zu # buf \"%s\" != \"%s\"\n",
                                    i + 1, buf, test_args[i].res);
                        errcnt++;
                } else {
                        if (verbose)
                                printf("successful result on index %zu, "
                                    "returned %d, got: \"%s\"; num = %jd, "
                                    "buflen = %zd, scale = %s, flags= %s.\n",
                                    i, r, buf, (intmax_t)test_args[i].num,
                                    blen, scale_str, flag_str);
                        else
                                printf("ok %zu\n", i + 1);
                }
                tested++;
        }
        free(buf);

        if (verbose)
                printf("total errors: %zu/%zu tests, %zu skipped\n", errcnt,
                    tested, skipped);

        if (errcnt)
                return 1;

        return 0;
}