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Diffstat (limited to 'src/getlimits.c')
| -rw-r--r-- | src/getlimits.c | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/src/getlimits.c b/src/getlimits.c new file mode 100644 index 0000000..25b2b72 --- /dev/null +++ b/src/getlimits.c @@ -0,0 +1,172 @@ +/* getlimits - print various platform dependent limits. + Copyright (C) 2008-2020 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; +} |