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| -rw-r--r-- | ChangeLog | 2 | ||||
| -rw-r--r-- | sysdeps/nacl/lll_timedlock_wait.c | 52 |
2 files changed, 54 insertions, 0 deletions
diff --git a/ChangeLog b/ChangeLog index 2e48f3317c..7fcd403700 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,7 @@ 2015-05-26 Roland McGrath <roland@hack.frob.com> + * sysdeps/nacl/lll_timedlock_wait.c: New file. + * nptl/lowlevellock.c (__lll_timedlock_wait): Moved ... * nptl/lll_timedlock_wait.c: ... to this new file. * nptl/Makefile (libpthread-routines): Add it. diff --git a/sysdeps/nacl/lll_timedlock_wait.c b/sysdeps/nacl/lll_timedlock_wait.c new file mode 100644 index 0000000000..df951ee8cb --- /dev/null +++ b/sysdeps/nacl/lll_timedlock_wait.c @@ -0,0 +1,52 @@ +/* Timed low level locking for pthread library. NaCl version. + Copyright (C) 2015 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#include <assert.h> +#include <atomic.h> +#include <errno.h> +#include <lowlevellock.h> +#include <sys/time.h> + + +/* This behaves the same as the generic version in nptl/. It's simpler + because it doesn't need to convert an absolute timeout to a relative + one (and back again in the lll_futex_timed_wait macro). */ + +int +__lll_timedlock_wait (int *futex, const struct timespec *abstime, int private) +{ + /* Reject invalid timeouts. */ + if (__glibc_unlikely (abstime->tv_nsec < 0) + || __glibc_unlikely (abstime->tv_nsec >= 1000000000)) + return EINVAL; + + /* Try locking. */ + int result = 0; + while (atomic_exchange_acq (futex, 2) != 0) + { + /* If *futex == 2, wait until woken or timeout. */ + result = __nacl_irt_futex.futex_wait_abs ((volatile int *) futex, 2, + abstime); + if (__glibc_likely (result == 0) + || __glibc_likely (result == ETIMEDOUT)) + break; + assert (result == EAGAIN); + } + + return result; +} |