/* $NetBSD: humanize_number.c,v 1.14 2008/04/28 20:22:59 martin Exp $ */ /* * Copyright (c) 1997, 1998, 1999, 2002 The NetBSD Foundation, Inc. * Copyright 2013 John-Mark Gurney * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, * NASA Ames Research Center, by Luke Mewburn and by Tomas Svensson. * * 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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. * * $FreeBSD: head/lib/libutil/humanize_number.c 256130 2013-10-07 22:22:57Z jmg $ */ #include #include #include #include #include #include #include #include static const int maxscale = 7; int humanize_number(char *buf, size_t len, int64_t quotient, const char *suffix, int scale, int flags) { const char *prefixes, *sep; int i, r, remainder, s1, s2, sign; int divisordeccut; int64_t divisor, max; size_t baselen; /* validate args */ if (buf == NULL) return (-1); if (scale < 0) return (-1); else if (scale >= maxscale && ((scale & ~(HN_AUTOSCALE|HN_GETSCALE)) != 0)) return (-1); if ((flags & HN_DIVISOR_1000) && (flags & HN_IEC_PREFIXES)) return (-1); /* Since so many callers don't check -1, NUL terminate the buffer */ if (len > 0) buf[0] = '\0'; if (suffix == NULL) suffix = ""; /* setup parameters */ remainder = 0; if (flags & HN_IEC_PREFIXES) { baselen = 2; /* * Use the prefixes for power of two recommended by * the International Electrotechnical Commission * (IEC) in IEC 80000-3 (i.e. Ki, Mi, Gi...). * * HN_IEC_PREFIXES implies a divisor of 1024 here * (use of HN_DIVISOR_1000 would have triggered * an assertion earlier). */ divisor = 1024; divisordeccut = 973; /* ceil(.95 * 1024) */ if (flags & HN_B) prefixes = "B\0\0Ki\0Mi\0Gi\0Ti\0Pi\0Ei"; else prefixes = "\0\0\0Ki\0Mi\0Gi\0Ti\0Pi\0Ei"; } else { baselen = 1; if (flags & HN_DIVISOR_1000) { divisor = 1000; divisordeccut = 950; if (flags & HN_B) prefixes = "B\0\0k\0\0M\0\0G\0\0T\0\0P\0\0E"; else prefixes = "\0\0\0k\0\0M\0\0G\0\0T\0\0P\0\0E"; } else { divisor = 1024; divisordeccut = 973; /* ceil(.95 * 1024) */ if (flags & HN_B) prefixes = "B\0\0K\0\0M\0\0G\0\0T\0\0P\0\0E"; else prefixes = "\0\0\0K\0\0M\0\0G\0\0T\0\0P\0\0E"; } } #define SCALE2PREFIX(scale) (&prefixes[(scale) * 3]) if (quotient < 0) { sign = -1; quotient = -quotient; baselen += 2; /* sign, digit */ } else { sign = 1; baselen += 1; /* digit */ } if (flags & HN_NOSPACE) sep = ""; else { sep = " "; baselen++; } baselen += strlen(suffix); /* Check if enough room for `x y' + suffix + `\0' */ if (len < baselen + 1) return (-1); if (scale & (HN_AUTOSCALE | HN_GETSCALE)) { /* See if there is additional columns can be used. */ for (max = 1, i = len - baselen; i-- > 0;) max *= 10; /* * Divide the number until it fits the given column. * If there will be an overflow by the rounding below, * divide once more. */ for (i = 0; (quotient >= max || (quotient == max - 1 && remainder >= divisordeccut)) && i < maxscale; i++) { remainder = quotient % divisor; quotient /= divisor; } if (scale & HN_GETSCALE) return (i); } else { for (i = 0; i < scale && i < maxscale; i++) { remainder = quotient % divisor; quotient /= divisor; } } /* * Generate base output */ r = snprintf(buf, len, "%" PRId64 "%s%s%s", sign * (quotient + (remainder + divisor / 2) / divisor), sep, SCALE2PREFIX(i), suffix); if ((flags & HN_FRACTIONAL) && (u_int)r + 3 <= len && i) { /* * If FRACTIONAL is specified output up to two fractional * digits, unless the value was not divided out. */ int64_t frac; int n; n = (int)len - r - 2; frac = 1; if (n > 2) /* max 2 fractional digits */ n = 2; while (n) { frac = frac * 10; --n; } s1 = (int)quotient + ((remainder * frac + divisor / 2) / divisor / frac); s2 = ((remainder * frac + divisor / 2) / divisor) % frac; r = snprintf(buf, len, "%d%s%d%s%s%s", sign * s1, localeconv()->decimal_point, s2, sep, SCALE2PREFIX(i), suffix); } else if ((flags & HN_DECIMAL) && (u_int)r + 3 <= len && (((quotient == 9 && remainder < divisordeccut) || quotient < 9) && i > 0)) { /* * If DECIMAL is specified and the value is <= 9.9 after * rounding, and it fits, add one fractional digit. */ s1 = (int)quotient + ((remainder * 10 + divisor / 2) / divisor / 10); s2 = ((remainder * 10 + divisor / 2) / divisor) % 10; r = snprintf(buf, len, "%d%s%d%s%s%s", sign * s1, localeconv()->decimal_point, s2, sep, SCALE2PREFIX(i), suffix); } return (r); }