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Diffstat (limited to 'nptl/sysdeps/unix/sysv/linux/s390/sem_trywait.c')
-rw-r--r--nptl/sysdeps/unix/sysv/linux/s390/sem_trywait.c49
1 files changed, 49 insertions, 0 deletions
diff --git a/nptl/sysdeps/unix/sysv/linux/s390/sem_trywait.c b/nptl/sysdeps/unix/sysv/linux/s390/sem_trywait.c
new file mode 100644
index 0000000000..0fa047b825
--- /dev/null
+++ b/nptl/sysdeps/unix/sysv/linux/s390/sem_trywait.c
@@ -0,0 +1,49 @@
+/* Copyright (C) 2003 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Martin Schwidefsky <schwidefsky@de.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, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <errno.h>
+#include <sysdep.h>
+#include <lowlevelsem.h>
+#include <internaltypes.h>
+
+#include <shlib-compat.h>
+
+
+int
+__new_sem_trywait (sem_t *sem)
+{
+ int oldval;
+ int newval;
+
+ /* Atomically decrement sem counter if it is > 0. */
+ lll_compare_and_swap ((int *) sem, oldval, newval,
+ "ltr %2,%1; jnp 1f; ahi %2,-1");
+ /* oldval != newval if the semaphore count has been decremented. */
+ if (oldval == newval)
+ {
+ __set_errno (EAGAIN);
+ return -1;
+ }
+ return 0;
+}
+versioned_symbol (libpthread, __new_sem_trywait, sem_trywait, GLIBC_2_1);
+#if SHLIB_COMPAT(libpthread, GLIBC_2_0, GLIBC_2_1)
+strong_alias (__new_sem_trywait, __old_sem_trywait)
+compat_symbol (libpthread, __old_sem_trywait, sem_trywait, GLIBC_2_0);
+#endif