lib/human.h

   1 /* human.h -- print human readable file size
   2
   3    Copyright (C) 1996-2007, 2009-2024 Free Software Foundation, Inc.
   4
   5    This program is free software: you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation, either version 3 of the License, or
   8    (at your option) any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  17
  18 /* Written by Paul Eggert and Larry McVoy.  */
  19
  20 #ifndef HUMAN_H_
  21 # define HUMAN_H_ 1
  22
  23 # include <limits.h>
  24 # include <stdint.h>
  25 # include <unistd.h>
  26
  27 # include <xstrtol.h>
  28
  29 /* A conservative bound on the maximum length of a human-readable string.
  30    The output can be the square of the largest uintmax_t, so double
  31    its size before converting to a bound.
  32    log10 (2.0) < 146/485.  Add 1 for integer division truncation.
  33    Also, the output can have a thousands separator between every digit,
  34    so multiply by MB_LEN_MAX + 1 and then subtract MB_LEN_MAX.
  35    Append 1 for a space before the suffix.
  36    Finally, append 3, the maximum length of a suffix.  */
  37 # define LONGEST_HUMAN_READABLE \
  38   ((2 * sizeof (uintmax_t) * CHAR_BIT * 146 / 485 + 1) * (MB_LEN_MAX + 1) \
  39    - MB_LEN_MAX + 1 + 3)
  40
  41 /* Options for human_readable.  */
  42 enum
  43 {
  44   /* Unless otherwise specified these options may be ORed together.  */
  45
  46   /* The following three options are mutually exclusive.  */
  47   /* Round to plus infinity (default).  */
  48   human_ceiling = 0,
  49   /* Round to nearest, ties to even.  */
  50   human_round_to_nearest = 1,
  51   /* Round to minus infinity.  */
  52   human_floor = 2,
  53
  54   /* Group digits together, e.g. "1,000,000".  This uses the
  55      locale-defined grouping; the traditional C locale does not group,
  56      so this has effect only if some other locale is in use.  */
  57   human_group_digits = 4,
  58
  59   /* When autoscaling, suppress ".0" at end.  */
  60   human_suppress_point_zero = 8,
  61
  62   /* Scale output and use SI-style units, ignoring the output block size.  */
  63   human_autoscale = 16,
  64
  65   /* Prefer base 1024 to base 1000.  */
  66   human_base_1024 = 32,
  67
  68   /* Prepend " " before unit symbol.  */
  69   human_space_before_unit = 64,
  70
  71   /* Append SI prefix, e.g. "k" or "M".  */
  72   human_SI = 128,
  73
  74   /* Append "B" (if base 1000) or "iB" (if base 1024) to SI prefix.  */
  75   human_B = 256
  76 };
  77
  78 char *human_readable (uintmax_t, char *, int, uintmax_t, uintmax_t);
  79
  80 enum strtol_error human_options (char const *, int *, uintmax_t *);
  81
  82 #endif /* HUMAN_H_ */