Mercurial > gnulib
view lib/timespec-sub.c @ 40198:5a34193cbc07
long-options: add parse_gnu_standard_options_only
Discussed in https://bugs.gnu.org/33468 .
* lib/long-options.c (parse_long_options): Use EXIT_SUCCESS instead
of 0.
(parse_gnu_standard_options_only): Add function to
process the GNU default options --help and --version and fail for any other
unknown long or short option. See
https://gnu.org/prep/standards/html_node/Command_002dLine-Interfaces.html .
* lib/long-options.h (parse_gnu_standard_options_only): Declare it.
* modules/long-options (depends-on): Add stdbool, exitfail.
* top/maint.mk (sc_prohibit_long_options_without_use): Update
syntax-check rule, add new function name.
author | Bernhard Voelker <mail@bernhard-voelker.de> |
---|---|
date | Thu, 29 Nov 2018 09:06:26 +0100 |
parents | b06060465f09 |
children |
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/* Subtract two struct timespec values. Copyright (C) 2011-2019 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 Paul Eggert. */ /* Return the difference between two timespec values A and B. On overflow, return an extremal value. This assumes 0 <= tv_nsec < TIMESPEC_HZ. */ #include <config.h> #include "timespec.h" #include "intprops.h" struct timespec timespec_sub (struct timespec a, struct timespec b) { time_t rs = a.tv_sec; time_t bs = b.tv_sec; int ns = a.tv_nsec - b.tv_nsec; int rns = ns; time_t tmin = TYPE_MINIMUM (time_t); time_t tmax = TYPE_MAXIMUM (time_t); if (ns < 0) { rns = ns + TIMESPEC_HZ; if (bs < tmax) bs++; else if (- TYPE_SIGNED (time_t) < rs) rs--; else goto low_overflow; } /* INT_SUBTRACT_WRAPV is not appropriate since time_t might be unsigned. In theory time_t might be narrower than int, so plain INT_SUBTRACT_OVERFLOW does not suffice. */ if (! INT_SUBTRACT_OVERFLOW (rs, bs) && tmin <= rs - bs && rs - bs <= tmax) rs -= bs; else { if (rs < 0) { low_overflow: rs = tmin; rns = 0; } else { rs = tmax; rns = TIMESPEC_HZ - 1; } } return make_timespec (rs, rns); }