1 files changed, 80 insertions, 0 deletions
diff --git a/libpthread/nptl/sem_close.c b/libpthread/nptl/sem_close.c
new file mode 100644
index 000000000..a2bcc7179
--- /dev/null
+++ b/libpthread/nptl/sem_close.c
@@ -0,0 +1,80 @@
+/* Copyright (C) 2002, 2003 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <errno.h>
+#include <search.h>
+#include <sys/mman.h>
+#include "semaphoreP.h"
+
+
+/* Global variables to parametrize the walk function.  This works
+   since we always have to use locks.  And we have to use the twalk
+   function since the entries are not sorted wrt the mapping
+   address.  */
+static sem_t *the_sem;
+static struct inuse_sem *rec;
+
+static void
+walker (const void *inodep, const VISIT which, const int depth)
+{
+  struct inuse_sem *nodep = *(struct inuse_sem **) inodep;
+
+  if (nodep->sem == the_sem)
+    rec = nodep;
+}
+
+
+int
+sem_close (sem_t *sem)
+{
+  int result = 0;
+
+  /* Get the lock.  */
+  lll_lock (__sem_mappings_lock);
+
+  /* Locate the entry for the mapping the caller provided.  */
+  rec = NULL;
+  the_sem = sem;
+  twalk (__sem_mappings, walker);
+  if  (rec != NULL)
+    {
+      /* Check the reference counter.  If it is going to be zero, free
+	 all the resources.  */
+      if (--rec->refcnt == 0)
+	{
+	  /* Remove the record from the tree.  */
+	  (void) tdelete (rec, &__sem_mappings, __sem_search);
+
+	  result = munmap (rec->sem, sizeof (sem_t));
+
+	  free (rec);
+	}
+    }
+  else
+    {
+      /* This is no valid semaphore.  */
+      result = -1;
+      __set_errno (EINVAL);
+    }
+
+  /* Release the lock.  */
+  lll_unlock (__sem_mappings_lock);
+
+  return result;
+}