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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 17:39:29 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 17:39:29 +0000
commit8ffec2a3aba6f114784e11f89ef1d57a096ae540 (patch)
treeccebcbad06203e8241a8e7249f8e6c478a3682ea /gnulib-tests/timespec-sub.c
parentInitial commit. (diff)
downloadcoreutils-8ffec2a3aba6f114784e11f89ef1d57a096ae540.tar.xz
coreutils-8ffec2a3aba6f114784e11f89ef1d57a096ae540.zip
Adding upstream version 8.32.upstream/8.32upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'gnulib-tests/timespec-sub.c')
-rw-r--r--gnulib-tests/timespec-sub.c65
1 files changed, 65 insertions, 0 deletions
diff --git a/gnulib-tests/timespec-sub.c b/gnulib-tests/timespec-sub.c
new file mode 100644
index 0000000..ee827a7
--- /dev/null
+++ b/gnulib-tests/timespec-sub.c
@@ -0,0 +1,65 @@
+/* Subtract two struct timespec values.
+
+ Copyright (C) 2011-2020 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 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;
+
+ if (ns < 0)
+ {
+ rns = ns + TIMESPEC_HZ;
+ time_t bs1;
+ if (!INT_ADD_WRAPV (bs, 1, &bs1))
+ bs = bs1;
+ else if (- TYPE_SIGNED (time_t) < rs)
+ rs--;
+ else
+ goto low_overflow;
+ }
+
+ if (INT_SUBTRACT_WRAPV (rs, bs, &rs))
+ {
+ if (0 < bs)
+ {
+ low_overflow:
+ rs = TYPE_MINIMUM (time_t);
+ rns = 0;
+ }
+ else
+ {
+ rs = TYPE_MAXIMUM (time_t);
+ rns = TIMESPEC_HZ - 1;
+ }
+ }
+
+ return make_timespec (rs, rns);
+}