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I used these shell commands: ../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright (cd ../glibc && git commit -am"[this commit message]") and then ignored the output, which consisted lines saying "FOO: warning: copyright statement not found" for each of 6694 files FOO. I then removed trailing white space from benchtests/bench-pthread-locks.c and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this diagnostic from Savannah: remote: *** pre-commit check failed ... remote: *** error: lines with trailing whitespace found remote: error: hook declined to update refs/heads/master
56 lines
1.6 KiB
C
56 lines
1.6 KiB
C
/* Lock a semaphore if it does not require blocking. Generic version.
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Copyright (C) 2005-2021 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, see
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<https://www.gnu.org/licenses/>. */
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#include <semaphore.h>
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#include <errno.h>
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#include <pt-internal.h>
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int
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__sem_waitfast (struct new_sem *isem, int definitive_result)
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{
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#if __HAVE_64B_ATOMICS
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uint64_t d = atomic_load_relaxed (&isem->data);
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do
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{
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if ((d & SEM_VALUE_MASK) == 0)
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break;
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if (atomic_compare_exchange_weak_acquire (&isem->data, &d, d - 1))
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/* Successful down. */
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return 0;
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}
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while (definitive_result);
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return -1;
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#else
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unsigned v = atomic_load_relaxed (&isem->value);
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do
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{
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if ((v >> SEM_VALUE_SHIFT) == 0)
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break;
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if (atomic_compare_exchange_weak_acquire (&isem->value,
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&v, v - (1 << SEM_VALUE_SHIFT)))
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/* Successful down. */
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return 0;
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}
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while (definitive_result);
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return -1;
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#endif
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}
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