1 files changed, 41 insertions, 13 deletions

diff --git a/libpthread/nptl/sysdeps/unix/sysv/linux/sem_wait.c b/libpthread/nptl/sysdeps/unix/sysv/linux/sem_wait.c
index 416d8634b..e661e09c8 100644
--- a/libpthread/nptl/sysdeps/unix/sysv/linux/sem_wait.c
+++ b/libpthread/nptl/sysdeps/unix/sysv/linux/sem_wait.c
@@ -1,5 +1,5 @@
 /* sem_wait -- wait on a semaphore.  Generic futex-using version.
-   Copyright (C) 2003 Free Software Foundation, Inc.
+   Copyright (C) 2003, 2007 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Paul Mackerras <paulus@au.ibm.com>, 2003.
 
@@ -23,34 +23,62 @@
 #include <lowlevellock.h>
 #include <internaltypes.h>
 #include <semaphore.h>
+
 #include <pthreadP.h>
 
 
+void
+attribute_hidden
+__sem_wait_cleanup (void *arg)
+{
+  struct new_sem *isem = (struct new_sem *) arg;
+
+  atomic_decrement (&isem->nwaiters);
+}
+
+
 int
 __new_sem_wait (sem_t *sem)
 {
-  /* First check for cancellation.  */
-  CANCELLATION_P (THREAD_SELF);
-
-  int *futex = (int *) sem;
+  struct new_sem *isem = (struct new_sem *) sem;
   int err;
 
-  do
-    {
-      if (atomic_decrement_if_positive (futex) > 0)
-	return 0;
+  if (atomic_decrement_if_positive (&isem->value) > 0)
+    return 0;
 
+  atomic_increment (&isem->nwaiters);
+
+  pthread_cleanup_push (__sem_wait_cleanup, isem);
+
+  while (1)
+    {
       /* Enable asynchronous cancellation.  Required by the standard.  */
       int oldtype = __pthread_enable_asynccancel ();
 
-      err = lll_futex_wait (futex, 0);
+      err = lll_futex_wait (&isem->value, 0,
+			    isem->private ^ FUTEX_PRIVATE_FLAG);
 
       /* Disable asynchronous cancellation.  */
       __pthread_disable_asynccancel (oldtype);
+
+      if (err != 0 && err != -EWOULDBLOCK)
+	{
+	  __set_errno (-err);
+	  err = -1;
+	  break;
+	}
+
+      if (atomic_decrement_if_positive (&isem->value) > 0)
+	{
+	  err = 0;
+	  break;
+	}
     }
-  while (err == 0 || err == -EWOULDBLOCK);
 
-  __set_errno (-err);
-  return -1;
+  pthread_cleanup_pop (0);
+
+  atomic_decrement (&isem->nwaiters);
+
+  return err;
 }
 weak_alias(__new_sem_wait, sem_wait)