diff options
Diffstat (limited to 'libpthread/nptl/sysdeps/unix/sysv/linux/sparc/sem_trywait.c')
-rw-r--r-- | libpthread/nptl/sysdeps/unix/sysv/linux/sparc/sem_trywait.c | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/libpthread/nptl/sysdeps/unix/sysv/linux/sparc/sem_trywait.c b/libpthread/nptl/sysdeps/unix/sysv/linux/sparc/sem_trywait.c new file mode 100644 index 000000000..36e859ba4 --- /dev/null +++ b/libpthread/nptl/sysdeps/unix/sysv/linux/sparc/sem_trywait.c @@ -0,0 +1,51 @@ +/* sem_trywait -- wait on a semaphore. SPARC version. + Copyright (C) 2003, 2006, 2007 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Paul Mackerras <paulus@au.ibm.com>, 2003. + + 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 <errno.h> +#include <sysdep.h> +#include <lowlevellock.h> +#include <internaltypes.h> +#include <semaphore.h> + + +int +sem_trywait (sem_t *sem) +{ + struct sparc_old_sem *isem = (struct sparc_old_sem *) sem; + int val; + + if (isem->value > 0) + { + if (__atomic_is_v9) + val = atomic_decrement_if_positive (&isem->value); + else + { + __sparc32_atomic_do_lock24 (&isem->lock); + val = isem->value; + if (val > 0) + isem->value = val - 1; + __sparc32_atomic_do_unlock24 (&isem->lock); + } + if (val > 0) + return 0; + } + + __set_errno (EAGAIN); + return -1; +} |