libpthread/nptl: core of the "Native Posix Threading Library" for uClibc

targetting arm,sh,i386,mips,sparc for now

Signed-off-by: Austin Foxley <austinf@cetoncorp.com>

1 files changed, 56 insertions, 0 deletions

diff --git a/libpthread/nptl/sysdeps/unix/sysv/linux/sem_wait.c b/libpthread/nptl/sysdeps/unix/sysv/linux/sem_wait.c
new file mode 100644
index 000000000..416d8634b
--- /dev/null
+++ b/libpthread/nptl/sysdeps/unix/sysv/linux/sem_wait.c
@@ -0,0 +1,56 @@
+/* sem_wait -- wait on a semaphore.  Generic futex-using version.
+   Copyright (C) 2003 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, 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>
+#include <pthreadP.h>
+
+
+int
+__new_sem_wait (sem_t *sem)
+{
+  /* First check for cancellation.  */
+  CANCELLATION_P (THREAD_SELF);
+
+  int *futex = (int *) sem;
+  int err;
+
+  do
+    {
+      if (atomic_decrement_if_positive (futex) > 0)
+	return 0;
+
+      /* Enable asynchronous cancellation.  Required by the standard.  */
+      int oldtype = __pthread_enable_asynccancel ();
+
+      err = lll_futex_wait (futex, 0);
+
+      /* Disable asynchronous cancellation.  */
+      __pthread_disable_asynccancel (oldtype);
+    }
+  while (err == 0 || err == -EWOULDBLOCK);
+
+  __set_errno (-err);
+  return -1;
+}
+weak_alias(__new_sem_wait, sem_wait)