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-rw-r--r--libpthread/nptl/sysdeps/unix/sysv/linux/sem_post.c41
1 files changed, 41 insertions, 0 deletions
diff --git a/libpthread/nptl/sysdeps/unix/sysv/linux/sem_post.c b/libpthread/nptl/sysdeps/unix/sysv/linux/sem_post.c
new file mode 100644
index 000000000..7f0b67918
--- /dev/null
+++ b/libpthread/nptl/sysdeps/unix/sysv/linux/sem_post.c
@@ -0,0 +1,41 @@
+/* sem_post -- post to a POSIX semaphore. Generic futex-using version.
+ Copyright (C) 2003, 2004 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Jakub Jelinek <jakub@redhat.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 <lowlevellock.h>
+#include <internaltypes.h>
+#include <semaphore.h>
+
+int
+__new_sem_post (sem_t *sem)
+{
+ int *futex = (int *) sem;
+
+ int nr = atomic_increment_val (futex);
+ int err = lll_futex_wake (futex, nr);
+ if (__builtin_expect (err, 0) < 0)
+ {
+ __set_errno (-err);
+ return -1;
+ }
+ return 0;
+}
+weak_alias(__new_sem_post, sem_post)