1 /* $NetBSD: humanize_number.c,v 1.13 2007/12/14 17:26:19 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1997, 1998, 1999, 2002 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, 9 * NASA Ames Research Center, by Luke Mewburn and by Tomas Svensson. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the NetBSD 22 * Foundation, Inc. and its contributors. 23 * 4. Neither the name of The NetBSD Foundation nor the names of its 24 * contributors may be used to endorse or promote products derived 25 * from this software without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 29 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 31 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 32 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 35 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 37 * POSSIBILITY OF SUCH DAMAGE. 38 */ 39 40 #include <sys/cdefs.h> 41 __FBSDID("$FreeBSD$"); 42 43 #include <sys/types.h> 44 #include <assert.h> 45 #include <inttypes.h> 46 #include <stdio.h> 47 #include <stdlib.h> 48 #include <string.h> 49 #include <locale.h> 50 #include <libutil.h> 51 52 int 53 humanize_number(char *buf, size_t len, int64_t bytes, 54 const char *suffix, int scale, int flags) 55 { 56 const char *prefixes, *sep; 57 int b, i, r, maxscale, s1, s2, sign; 58 int64_t divisor, max; 59 size_t baselen; 60 61 assert(buf != NULL); 62 assert(suffix != NULL); 63 assert(scale >= 0); 64 65 if (flags & HN_DIVISOR_1000) { 66 /* SI for decimal multiplies */ 67 divisor = 1000; 68 if (flags & HN_B) 69 prefixes = "B\0k\0M\0G\0T\0P\0E"; 70 else 71 prefixes = "\0\0k\0M\0G\0T\0P\0E"; 72 } else { 73 /* 74 * binary multiplies 75 * XXX IEC 60027-2 recommends Ki, Mi, Gi... 76 */ 77 divisor = 1024; 78 if (flags & HN_B) 79 prefixes = "B\0K\0M\0G\0T\0P\0E"; 80 else 81 prefixes = "\0\0K\0M\0G\0T\0P\0E"; 82 } 83 84 #define SCALE2PREFIX(scale) (&prefixes[(scale) << 1]) 85 maxscale = 7; 86 87 if (scale >= maxscale && 88 (scale & (HN_AUTOSCALE | HN_GETSCALE)) == 0) 89 return (-1); 90 91 if (buf == NULL || suffix == NULL) 92 return (-1); 93 94 if (len > 0) 95 buf[0] = '\0'; 96 if (bytes < 0) { 97 sign = -1; 98 bytes *= -100; 99 baselen = 3; /* sign, digit, prefix */ 100 } else { 101 sign = 1; 102 bytes *= 100; 103 baselen = 2; /* digit, prefix */ 104 } 105 if (flags & HN_NOSPACE) 106 sep = ""; 107 else { 108 sep = " "; 109 baselen++; 110 } 111 baselen += strlen(suffix); 112 113 /* Check if enough room for `x y' + suffix + `\0' */ 114 if (len < baselen + 1) 115 return (-1); 116 117 if (scale & (HN_AUTOSCALE | HN_GETSCALE)) { 118 /* See if there is additional columns can be used. */ 119 for (max = 100, i = len - baselen; i-- > 0;) 120 max *= 10; 121 122 /* 123 * Divide the number until it fits the given column. 124 * If there will be an overflow by the rounding below, 125 * divide once more. 126 */ 127 for (i = 0; bytes >= max - 50 && i < maxscale; i++) 128 bytes /= divisor; 129 130 if (scale & HN_GETSCALE) 131 return (i); 132 } else 133 for (i = 0; i < scale && i < maxscale; i++) 134 bytes /= divisor; 135 136 /* If a value <= 9.9 after rounding and ... */ 137 if (bytes < 995 && i > 0 && flags & HN_DECIMAL) { 138 /* baselen + \0 + .N */ 139 if (len < baselen + 1 + 2) 140 return (-1); 141 b = ((int)bytes + 5) / 10; 142 s1 = b / 10; 143 s2 = b % 10; 144 r = snprintf(buf, len, "%d%s%d%s%s%s", 145 sign * s1, localeconv()->decimal_point, s2, 146 sep, SCALE2PREFIX(i), suffix); 147 } else 148 r = snprintf(buf, len, "%" PRId64 "%s%s%s", 149 sign * ((bytes + 50) / 100), 150 sep, SCALE2PREFIX(i), suffix); 151 152 return (r); 153 } 154