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/* getlimits - print various platform dependent limits.
Copyright (C) 2008-2019 Free Software Foundation, Inc.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>. */
/* Written by Pádraig Brady */
#include <config.h> /* sets _FILE_OFFSET_BITS=64 etc. */
#include <stdio.h>
#include <sys/types.h>
#include <float.h>
#include "ftoastr.h"
#include "system.h"
#include "long-options.h"
#define PROGRAM_NAME "getlimits"
#define AUTHORS proper_name ("Padraig Brady")
#ifndef TIME_T_MAX
# define TIME_T_MAX TYPE_MAXIMUM (time_t)
#endif
#ifndef TIME_T_MIN
# define TIME_T_MIN TYPE_MINIMUM (time_t)
#endif
#ifndef SSIZE_MIN
# define SSIZE_MIN TYPE_MINIMUM (ssize_t)
#endif
#ifndef PID_T_MIN
# define PID_T_MIN TYPE_MINIMUM (pid_t)
#endif
/* These are not interesting to print.
* Instead of these defines it would be nice to be able to do
* #ifdef (TYPE##_MIN) in function macro below. */
#define SIZE_MIN 0
#define UCHAR_MIN 0
#define UINT_MIN 0
#define ULONG_MIN 0
#define UINTMAX_MIN 0
#define UID_T_MIN 0
#define GID_T_MIN 0
void
usage (int status)
{
if (status != EXIT_SUCCESS)
emit_try_help ();
else
{
printf (_("\
Usage: %s\n\
"), program_name);
fputs (_("\
Output platform dependent limits in a format useful for shell scripts.\n\
\n\
"), stdout);
fputs (HELP_OPTION_DESCRIPTION, stdout);
fputs (VERSION_OPTION_DESCRIPTION, stdout);
emit_ancillary_info (PROGRAM_NAME);
}
exit (status);
}
/* Add one to the absolute value of the number whose textual
representation is BUF + 1. Do this in-place, in the buffer.
Return a pointer to the result, which is normally BUF + 1, but is
BUF if the representation grew in size. */
static char const *
decimal_absval_add_one (char *buf)
{
bool negative = (buf[1] == '-');
char *absnum = buf + 1 + negative;
char *p = absnum + strlen (absnum);
absnum[-1] = '0';
while (*--p == '9')
*p = '0';
++*p;
char *result = MIN (absnum, p);
if (negative)
*--result = '-';
return result;
}
#define PRINT_FLOATTYPE(N, T, FTOASTR, BUFSIZE) \
static void \
N (T x) \
{ \
char buf[BUFSIZE]; \
FTOASTR (buf, sizeof buf, FTOASTR_LEFT_JUSTIFY, 0, x); \
puts (buf); \
}
PRINT_FLOATTYPE (print_FLT, float, ftoastr, FLT_BUFSIZE_BOUND)
PRINT_FLOATTYPE (print_DBL, double, dtoastr, DBL_BUFSIZE_BOUND)
PRINT_FLOATTYPE (print_LDBL, long double, ldtoastr, LDBL_BUFSIZE_BOUND)
int
main (int argc, char **argv)
{
char limit[1 + MAX (INT_BUFSIZE_BOUND (intmax_t),
INT_BUFSIZE_BOUND (uintmax_t))];
initialize_main (&argc, &argv);
set_program_name (argv[0]);
setlocale (LC_ALL, "");
bindtextdomain (PACKAGE, LOCALEDIR);
textdomain (PACKAGE);
initialize_exit_failure (EXIT_FAILURE);
atexit (close_stdout);
parse_long_options (argc, argv, PROGRAM_NAME, PACKAGE_NAME, VERSION,
usage, AUTHORS, (char const *) NULL);
#define print_int(TYPE) \
sprintf (limit + 1, "%"PRIuMAX, (uintmax_t) TYPE##_MAX); \
printf (#TYPE"_MAX=%s\n", limit + 1); \
printf (#TYPE"_OFLOW=%s\n", decimal_absval_add_one (limit)); \
if (TYPE##_MIN) \
{ \
sprintf (limit + 1, "%"PRIdMAX, (intmax_t) TYPE##_MIN); \
printf (#TYPE"_MIN=%s\n", limit + 1); \
printf (#TYPE"_UFLOW=%s\n", decimal_absval_add_one (limit)); \
}
#define print_float(TYPE) \
printf (#TYPE"_MIN="); print_##TYPE (TYPE##_MIN); \
printf (#TYPE"_MAX="); print_##TYPE (TYPE##_MAX);
/* Variable sized ints */
print_int (CHAR);
print_int (SCHAR);
print_int (UCHAR);
print_int (SHRT);
print_int (INT);
print_int (UINT);
print_int (LONG);
print_int (ULONG);
print_int (SIZE);
print_int (SSIZE);
print_int (TIME_T);
print_int (UID_T);
print_int (GID_T);
print_int (PID_T);
print_int (OFF_T);
print_int (INTMAX);
print_int (UINTMAX);
/* Variable sized floats */
print_float (FLT);
print_float (DBL);
print_float (LDBL);
return EXIT_SUCCESS;
}