humanize_number.c revision 335891
1101776Stjr/* $NetBSD: humanize_number.c,v 1.14 2008/04/28 20:22:59 martin Exp $ */ 2132498Stjr 3101776Stjr/* 4101776Stjr * Copyright (c) 1997, 1998, 1999, 2002 The NetBSD Foundation, Inc. 5227753Stheraven * Copyright 2013 John-Mark Gurney <jmg@FreeBSD.org> 6227753Stheraven * All rights reserved. 7227753Stheraven * 8227753Stheraven * This code is derived from software contributed to The NetBSD Foundation 9227753Stheraven * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, 10101776Stjr * NASA Ames Research Center, by Luke Mewburn and by Tomas Svensson. 11101776Stjr * 12101776Stjr * Redistribution and use in source and binary forms, with or without 13101776Stjr * modification, are permitted provided that the following conditions 14101776Stjr * are met: 15101776Stjr * 1. Redistributions of source code must retain the above copyright 16101776Stjr * notice, this list of conditions and the following disclaimer. 17101776Stjr * 2. Redistributions in binary form must reproduce the above copyright 18101776Stjr * notice, this list of conditions and the following disclaimer in the 19101776Stjr * documentation and/or other materials provided with the distribution. 20101776Stjr * 21101776Stjr * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 22101776Stjr * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 23101776Stjr * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 24101776Stjr * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 25101776Stjr * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 26101776Stjr * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 27101776Stjr * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 28101776Stjr * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 29101776Stjr * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 30101776Stjr * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 31101776Stjr * POSSIBILITY OF SUCH DAMAGE. 32101776Stjr */ 33101776Stjr 34101776Stjr#include <sys/cdefs.h> 35101776Stjr__FBSDID("$FreeBSD: stable/10/lib/libutil/humanize_number.c 335891 2018-07-03 14:57:11Z robak $"); 36101776Stjr 37101776Stjr#include <sys/types.h> 38132498Stjr#include <assert.h> 39101776Stjr#include <inttypes.h> 40101776Stjr#include <stdio.h> 41101776Stjr#include <stdlib.h> 42101776Stjr#include <string.h> 43132498Stjr#include <locale.h> 44101776Stjr#include <libutil.h> 45101776Stjr 46227753Stheravenstatic const int maxscale = 6; 47101776Stjr 48305577Sacheint 49321074Skibhumanize_number(char *buf, size_t len, int64_t quotient, 50132498Stjr const char *suffix, int scale, int flags) 51132498Stjr{ 52132498Stjr const char *prefixes, *sep; 53227753Stheraven int i, r, remainder, s1, s2, sign; 54227753Stheraven int divisordeccut; 55101776Stjr int64_t divisor, max; 56321074Skib size_t baselen; 57103678Stjr 58101776Stjr /* Since so many callers don't check -1, NUL terminate the buffer */ 59103678Stjr if (len > 0) 60305577Sache buf[0] = '\0'; 61103678Stjr 62103678Stjr /* validate args */ 63103678Stjr if (buf == NULL || suffix == NULL) 64101776Stjr return (-1); 65305577Sache if (scale < 0) 66305577Sache return (-1); 67305577Sache else if (scale > maxscale && 68305577Sache ((scale & ~(HN_AUTOSCALE|HN_GETSCALE)) != 0)) 69132498Stjr return (-1); 70305577Sache if ((flags & HN_DIVISOR_1000) && (flags & HN_IEC_PREFIXES)) 71132498Stjr return (-1); 72305577Sache 73305577Sache /* setup parameters */ 74132498Stjr remainder = 0; 75132498Stjr 76132498Stjr if (flags & HN_IEC_PREFIXES) { 77227753Stheraven baselen = 2; 78132498Stjr /* 79178287Sjhb * Use the prefixes for power of two recommended by 80305577Sache * the International Electrotechnical Commission 81132498Stjr * (IEC) in IEC 80000-3 (i.e. Ki, Mi, Gi...). 82305577Sache * 83103678Stjr * HN_IEC_PREFIXES implies a divisor of 1024 here 84305577Sache * (use of HN_DIVISOR_1000 would have triggered 85132498Stjr * an assertion earlier). 86132498Stjr */ 87132498Stjr divisor = 1024; 88132498Stjr divisordeccut = 973; /* ceil(.95 * 1024) */ 89132498Stjr if (flags & HN_B) 90132498Stjr prefixes = "B\0\0Ki\0Mi\0Gi\0Ti\0Pi\0Ei"; 91132498Stjr else 92132498Stjr prefixes = "\0\0\0Ki\0Mi\0Gi\0Ti\0Pi\0Ei"; 93136092Sstefanf } else { 94136092Sstefanf baselen = 1; 95101776Stjr if (flags & HN_DIVISOR_1000) { 96132498Stjr divisor = 1000; 97132498Stjr divisordeccut = 950; 98132498Stjr if (flags & HN_B) 99132498Stjr prefixes = "B\0\0k\0\0M\0\0G\0\0T\0\0P\0\0E"; 100305577Sache else 101305577Sache prefixes = "\0\0\0k\0\0M\0\0G\0\0T\0\0P\0\0E"; 102305577Sache } else { 103305577Sache divisor = 1024; 104305577Sache divisordeccut = 973; /* ceil(.95 * 1024) */ 105305577Sache if (flags & HN_B) 106305577Sache prefixes = "B\0\0K\0\0M\0\0G\0\0T\0\0P\0\0E"; 107305577Sache else 108305577Sache prefixes = "\0\0\0K\0\0M\0\0G\0\0T\0\0P\0\0E"; 109305577Sache } 110305577Sache } 111132498Stjr 112132498Stjr#define SCALE2PREFIX(scale) (&prefixes[(scale) * 3]) 113132498Stjr 114305577Sache if (quotient < 0) { 115199784Swollman sign = -1; 116321074Skib quotient = -quotient; 117321074Skib baselen += 2; /* sign, digit */ 118321074Skib } else { 119321074Skib sign = 1; 120103678Stjr baselen += 1; /* digit */ 121103678Stjr } 122321074Skib if (flags & HN_NOSPACE) 123321074Skib sep = ""; 124101776Stjr else { 125305577Sache sep = " "; 126227753Stheraven baselen++; 127227753Stheraven } 128227753Stheraven baselen += strlen(suffix); 129227753Stheraven 130227753Stheraven /* Check if enough room for `x y' + suffix + `\0' */ 131 if (len < baselen + 1) 132 return (-1); 133 134 if (scale & (HN_AUTOSCALE | HN_GETSCALE)) { 135 /* See if there is additional columns can be used. */ 136 for (max = 1, i = len - baselen; i-- > 0;) 137 max *= 10; 138 139 /* 140 * Divide the number until it fits the given column. 141 * If there will be an overflow by the rounding below, 142 * divide once more. 143 */ 144 for (i = 0; 145 (quotient >= max || (quotient == max - 1 && 146 (remainder >= divisordeccut || remainder >= 147 divisor / 2))) && i < maxscale; i++) { 148 remainder = quotient % divisor; 149 quotient /= divisor; 150 } 151 152 if (scale & HN_GETSCALE) 153 return (i); 154 } else { 155 for (i = 0; i < scale && i < maxscale; i++) { 156 remainder = quotient % divisor; 157 quotient /= divisor; 158 } 159 } 160 161 /* If a value <= 9.9 after rounding and ... */ 162 /* 163 * XXX - should we make sure there is enough space for the decimal 164 * place and if not, don't do HN_DECIMAL? 165 */ 166 if (((quotient == 9 && remainder < divisordeccut) || quotient < 9) && 167 i > 0 && flags & HN_DECIMAL) { 168 s1 = (int)quotient + ((remainder * 10 + divisor / 2) / 169 divisor / 10); 170 s2 = ((remainder * 10 + divisor / 2) / divisor) % 10; 171 r = snprintf(buf, len, "%d%s%d%s%s%s", 172 sign * s1, localeconv()->decimal_point, s2, 173 sep, SCALE2PREFIX(i), suffix); 174 } else 175 r = snprintf(buf, len, "%" PRId64 "%s%s%s", 176 sign * (quotient + (remainder + divisor / 2) / divisor), 177 sep, SCALE2PREFIX(i), suffix); 178 179 return (r); 180} 181