1 /* human.c -- print human readable file size
2 Copyright (C) 1996, 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2, or (at your option)
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software Foundation,
16 Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
18 /* Originally contributed by lm@sgi.com;
19 --si, output block size selection, and large file support
20 added by eggert@twinsun.com. */
26 #include <sys/types.h>
39 #ifndef HAVE_DECL_GETENV
40 "this configure-time declaration test was not run"
48 # define _(Text) gettext (Text)
59 static const char suffixes[] =
72 /* If INEXACT_STYLE is not human_round_to_even, and if easily
73 possible, adjust VALUE according to the style. */
75 adjust_value (enum human_inexact_style inexact_style, double value)
77 /* Do not use the floor or ceil functions, as that would mean
78 linking with the standard math library, which is a porting pain.
79 So leave the value alone if it is too large to easily round. */
80 if (inexact_style != human_round_to_even && value < (uintmax_t) -1)
83 value = u + (inexact_style == human_ceiling && u != value);
89 /* Like human_readable_inexact, except always round to even. */
91 human_readable (uintmax_t n, char *buf,
92 int from_block_size, int output_block_size)
94 return human_readable_inexact (n, buf, from_block_size, output_block_size,
98 /* Convert N to a human readable format in BUF.
100 N is expressed in units of FROM_BLOCK_SIZE. FROM_BLOCK_SIZE must
103 OUTPUT_BLOCK_SIZE must be nonzero. If it is positive, use units of
104 OUTPUT_BLOCK_SIZE in the output number.
106 Use INEXACT_STYLE to determine whether to take the ceiling or floor
107 of any result that cannot be expressed exactly.
109 If OUTPUT_BLOCK_SIZE is negative, use a format like "127k" if
110 possible, using powers of -OUTPUT_BLOCK_SIZE; otherwise, use
111 ordinary decimal format. Normally -OUTPUT_BLOCK_SIZE is either
112 1000 or 1024; it must be at least 2. Most people visually process
113 strings of 3-4 digits effectively, but longer strings of digits are
114 more prone to misinterpretation. Hence, converting to an
115 abbreviated form usually improves readability. Use a suffix
116 indicating which power is being used. For example, assuming
117 -OUTPUT_BLOCK_SIZE is 1024, 8500 would be converted to 8.3k,
118 133456345 to 127M, 56990456345 to 53G, and so on. Numbers smaller
119 than -OUTPUT_BLOCK_SIZE aren't modified. */
122 human_readable_inexact (uintmax_t n, char *buf,
123 int from_block_size, int output_block_size,
124 enum human_inexact_style inexact_style)
133 /* 0 means adjusted N == AMT.TENTHS;
134 1 means AMT.TENTHS < adjusted N < AMT.TENTHS + 0.05;
135 2 means adjusted N == AMT.TENTHS + 0.05;
136 3 means AMT.TENTHS + 0.05 < adjusted N < AMT.TENTHS + 0.1. */
139 if (output_block_size < 0)
141 base = -output_block_size;
147 to_block_size = output_block_size;
150 p = buf + LONGEST_HUMAN_READABLE;
154 /* Suppress `used before initialized' warning. */
158 /* Adjust AMT out of FROM_BLOCK_SIZE units and into TO_BLOCK_SIZE units. */
165 if (to_block_size <= from_block_size
166 ? (from_block_size % to_block_size != 0
167 || (multiplier = from_block_size / to_block_size,
168 (amt = n * multiplier) / multiplier != n))
169 : (from_block_size == 0
170 || to_block_size % from_block_size != 0
171 || (divisor = to_block_size / from_block_size,
172 r10 = (n % divisor) * 10,
173 r2 = (r10 % divisor) * 2,
175 tenths = r10 / divisor,
176 rounding = r2 < divisor ? 0 < r2 : 2 + (divisor < r2),
179 /* Either the result cannot be computed easily using uintmax_t,
180 or from_block_size is zero. Fall back on floating point.
181 FIXME: This can yield answers that are slightly off. */
183 double damt = n * (from_block_size / (double) to_block_size);
186 sprintf (buf, "%.0f", adjust_value (inexact_style, damt));
197 while (e * base <= damt && power < sizeof suffixes - 1);
201 sprintf (buf, "%.1f%c", adjust_value (inexact_style, damt),
203 if (4 < strlen (buf))
204 sprintf (buf, "%.0f%c",
205 adjust_value (inexact_style, damt * 10) / 10,
213 /* Use power of BASE notation if adjusted AMT is large enough. */
215 if (base && base <= amt)
221 int r10 = (amt % base) * 10 + tenths;
222 int r2 = (r10 % base) * 2 + (rounding >> 1);
225 rounding = (r2 < base
227 : 2 + (base < r2 + rounding));
230 while (base <= amt && power < sizeof suffixes - 1);
232 *--p = suffixes[power];
236 if (2 * (1 - (int) inexact_style)
237 < rounding + (tenths & (inexact_style == human_round_to_even)))
253 tenths = rounding = 0;
258 if (inexact_style == human_ceiling
259 ? 0 < tenths + rounding
260 : inexact_style == human_round_to_even
261 ? 5 < tenths + (2 < rounding + (amt & 1))
262 : /* inexact_style == human_floor */ 0)
266 if (amt == base && power < sizeof suffixes - 1)
268 *p = suffixes[power + 1];
276 *--p = '0' + (int) (amt % 10);
277 while ((amt /= 10) != 0);
283 /* The default block size used for output. This number may change in
284 the future as disks get larger. */
285 #ifndef DEFAULT_BLOCK_SIZE
286 # define DEFAULT_BLOCK_SIZE 1024
289 static char const *const block_size_args[] = { "human-readable", "si", 0 };
290 static int const block_size_types[] = { -1024, -1000 };
293 default_block_size (void)
295 return getenv ("POSIXLY_CORRECT") ? 512 : DEFAULT_BLOCK_SIZE;
299 humblock (char const *spec, int *block_size)
303 if (! spec && ! (spec = getenv ("BLOCK_SIZE")))
304 *block_size = default_block_size ();
305 else if (0 <= (i = ARGMATCH (spec, block_size_args, block_size_types)))
306 *block_size = block_size_types[i];
311 strtol_error e = xstrtoul (spec, &ptr, 0, &val, "eEgGkKmMpPtTyYzZ0");
315 return LONGINT_INVALID_SUFFIX_CHAR;
316 if ((int) val < 0 || val != (int) val)
317 return LONGINT_OVERFLOW;
318 *block_size = (int) val;
325 human_block_size (char const *spec, int report_errors, int *block_size)
327 strtol_error e = humblock (spec, block_size);
328 if (*block_size == 0)
330 *block_size = default_block_size ();
333 if (e != LONGINT_OK && report_errors)
334 STRTOL_FATAL_ERROR (spec, _("block size"), e);