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Also, change sources.redhat.com to sourceware.org. This patch was automatically generated by running the following shell script, which uses GNU sed, and which avoids modifying files imported from upstream: sed -ri ' s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g ' \ $(find $(git ls-files) -prune -type f \ ! -name '*.po' \ ! -name 'ChangeLog*' \ ! -path COPYING ! -path COPYING.LIB \ ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \ ! -path manual/texinfo.tex ! -path scripts/config.guess \ ! -path scripts/config.sub ! -path scripts/install-sh \ ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \ ! -path INSTALL ! -path locale/programs/charmap-kw.h \ ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \ ! '(' -name configure \ -execdir test -f configure.ac -o -f configure.in ';' ')' \ ! '(' -name preconfigure \ -execdir test -f preconfigure.ac ';' ')' \ -print) and then by running 'make dist-prepare' to regenerate files built from the altered files, and then executing the following to cleanup: chmod a+x sysdeps/unix/sysv/linux/riscv/configure # Omit irrelevant whitespace and comment-only changes, # perhaps from a slightly-different Autoconf version. git checkout -f \ sysdeps/csky/configure \ sysdeps/hppa/configure \ sysdeps/riscv/configure \ sysdeps/unix/sysv/linux/csky/configure # Omit changes that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines git checkout -f \ sysdeps/powerpc/powerpc64/ppc-mcount.S \ sysdeps/unix/sysv/linux/s390/s390-64/syscall.S # Omit change that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
102 lines
3.1 KiB
C
102 lines
3.1 KiB
C
/* sem_wait -- wait on a semaphore. Generic futex-using version.
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Copyright (C) 2003-2019 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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Contributed by Paul Mackerras <paulus@au.ibm.com>, 2003.
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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 <lowlevellock.h> /* lll_futex* used by the old code. */
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#include "sem_waitcommon.c"
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int
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__new_sem_wait (sem_t *sem)
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{
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/* We need to check whether we need to act upon a cancellation request here
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because POSIX specifies that cancellation points "shall occur" in
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sem_wait and sem_timedwait, which also means that they need to check
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this regardless whether they block or not (unlike "may occur"
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functions). See the POSIX Rationale for this requirement: Section
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"Thread Cancellation Overview" [1] and austin group issue #1076 [2]
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for thoughs on why this may be a suboptimal design.
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[1] http://pubs.opengroup.org/onlinepubs/9699919799/xrat/V4_xsh_chap02.html
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[2] http://austingroupbugs.net/view.php?id=1076 for thoughts on why this
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*/
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__pthread_testcancel ();
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if (__new_sem_wait_fast ((struct new_sem *) sem, 0) == 0)
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return 0;
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else
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return __new_sem_wait_slow ((struct new_sem *) sem,
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CLOCK_REALTIME, NULL);
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}
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versioned_symbol (libpthread, __new_sem_wait, sem_wait, GLIBC_2_1);
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#if SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_1)
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int
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attribute_compat_text_section
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__old_sem_wait (sem_t *sem)
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{
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int *futex = (int *) sem;
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int err;
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do
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{
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if (atomic_decrement_if_positive (futex) > 0)
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return 0;
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/* Always assume the semaphore is shared. */
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err = lll_futex_wait_cancel (futex, 0, LLL_SHARED);
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}
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while (err == 0 || err == -EWOULDBLOCK);
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__set_errno (-err);
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return -1;
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}
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compat_symbol (libpthread, __old_sem_wait, sem_wait, GLIBC_2_0);
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#endif
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int
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__new_sem_trywait (sem_t *sem)
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{
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/* We must not fail spuriously, so require a definitive result even if this
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may lead to a long execution time. */
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if (__new_sem_wait_fast ((struct new_sem *) sem, 1) == 0)
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return 0;
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__set_errno (EAGAIN);
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return -1;
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}
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versioned_symbol (libpthread, __new_sem_trywait, sem_trywait, GLIBC_2_1);
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#if SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_1)
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int
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__old_sem_trywait (sem_t *sem)
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{
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int *futex = (int *) sem;
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int val;
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if (*futex > 0)
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{
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val = atomic_decrement_if_positive (futex);
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if (val > 0)
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return 0;
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}
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__set_errno (EAGAIN);
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return -1;
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}
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compat_symbol (libpthread, __old_sem_trywait, sem_trywait, GLIBC_2_0);
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#endif
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