about summary refs log tree commit diff
path: root/REORG.TODO/nptl/sem_getvalue.c
diff options
context:
space:
mode:
Diffstat (limited to 'REORG.TODO/nptl/sem_getvalue.c')
-rw-r--r--REORG.TODO/nptl/sem_getvalue.c55
1 files changed, 55 insertions, 0 deletions
diff --git a/REORG.TODO/nptl/sem_getvalue.c b/REORG.TODO/nptl/sem_getvalue.c
new file mode 100644
index 0000000000..8dfc1cde41
--- /dev/null
+++ b/REORG.TODO/nptl/sem_getvalue.c
@@ -0,0 +1,55 @@
+/* Copyright (C) 2002-2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
+
+   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 <semaphore.h>
+#include <shlib-compat.h>
+#include "semaphoreP.h"
+#include <atomic.h>
+
+
+int
+__new_sem_getvalue (sem_t *sem, int *sval)
+{
+  struct new_sem *isem = (struct new_sem *) sem;
+
+  /* XXX Check for valid SEM parameter.  */
+  /* FIXME This uses relaxed MO, even though POSIX specifies that this function
+     should be linearizable.  However, its debatable whether linearizability
+     is the right requirement.  We need to follow up with POSIX and, if
+     necessary, use a stronger MO here and elsewhere (e.g., potentially
+     release MO in all places where we consume a token).  */
+
+#if __HAVE_64B_ATOMICS
+  *sval = atomic_load_relaxed (&isem->data) & SEM_VALUE_MASK;
+#else
+  *sval = atomic_load_relaxed (&isem->value) >> SEM_VALUE_SHIFT;
+#endif
+
+  return 0;
+}
+versioned_symbol (libpthread, __new_sem_getvalue, sem_getvalue, GLIBC_2_1);
+#if SHLIB_COMPAT(libpthread, GLIBC_2_0, GLIBC_2_1)
+int
+__old_sem_getvalue (sem_t *sem, int *sval)
+{
+  struct old_sem *isem = (struct old_sem *) sem;
+  *sval = isem->value;
+  return 0;
+}
+compat_symbol (libpthread, __old_sem_getvalue, sem_getvalue, GLIBC_2_0);
+#endif