1 files changed, 126 insertions, 0 deletions
diff --git a/nptl/sysdeps/pthread/pthread_cond_wait.c b/nptl/sysdeps/pthread/pthread_cond_wait.c
new file mode 100644
index 0000000000..d0b63bd8df
--- /dev/null
+++ b/nptl/sysdeps/pthread/pthread_cond_wait.c
@@ -0,0 +1,126 @@
+/* Copyright (C) 2003 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Martin Schwidefsky <schwidefsky@de.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 <endian.h>
+#include <errno.h>
+#include <sysdep.h>
+#include <lowlevellock.h>
+#include <pthread.h>
+#include <pthreadP.h>
+
+#include <shlib-compat.h>
+
+
+void
+__attribute__ ((visibility ("hidden")))
+__condvar_cleanup (void *arg)
+{
+  pthread_cond_t *cond = (pthread_cond_t *) arg;
+
+  /* We are going to modify shared data.  */
+  lll_mutex_lock (cond->__data.__lock);
+
+  /* This thread is not waiting anymore.  Adjust the sequence counters
+     appropriately.  */
+  ++cond->__data.__wakeup_seq;
+  ++cond->__data.__woken_seq;
+
+  /* We are done.  */
+  lll_mutex_unlock (cond->__data.__lock);
+}
+
+
+int
+__pthread_cond_wait (cond, mutex)
+     pthread_cond_t *cond;
+     pthread_mutex_t *mutex;
+{
+  struct _pthread_cleanup_buffer buffer;
+
+  /* Make sure we are along.  */
+  lll_mutex_lock (cond->__data.__lock);
+
+  /* Now we can release the mutex.  */
+  __pthread_mutex_unlock_internal (mutex);
+
+  /* We have one new user of the condvar.  */
+  ++cond->__data.__total_seq;
+
+  /* Before we block we enable cancellation.  Therefore we have to
+     install a cancellation handler.  */
+  __pthread_cleanup_push (&buffer, __condvar_cleanup, cond);
+
+  /* The current values of the wakeup counter.  The "woken" counter
+     must exceed this value.  */
+  unsigned long long int val;
+  unsigned long long int seq;
+  val = seq = cond->__data.__wakeup_seq;
+
+  /* The futex syscall operates on a 32-bit word.  That is fine, we
+     just use the low 32 bits of the sequence counter.  */
+#if BYTE_ORDER == LITTLE_ENDIAN
+  int *futex = ((int *) (&cond->__data.__wakeup_seq));
+#elif BYTE_ORDER == BIG_ENDIAN
+  int *futex = ((int *) (&cond->__data.__wakeup_seq)) + 1;
+#else
+# error "No valid byte order"
+#endif
+
+  while (1)
+    {
+      /* Prepare to wait.  Release the condvar futex.  */
+      lll_mutex_unlock (cond->__data.__lock);
+
+      /* Enable asynchronous cancellation.  Required by the standard.  */
+      int oldtype = __pthread_enable_asynccancel ();
+
+      /* Wait until woken by signal or broadcast.  Note that we
+	 truncate the 'val' value to 32 bits.  */
+      lll_futex_wait (futex, (unsigned int) val);
+
+      /* Disable asynchronous cancellation.  */
+      __pthread_disable_asynccancel (oldtype);
+
+      /* We are going to look at shared data again, so get the lock.  */
+      lll_mutex_lock(cond->__data.__lock);
+
+      /* Check whether we are eligible for wakeup.  */
+      val = cond->__data.__wakeup_seq;
+      if (cond->__data.__woken_seq >= seq
+	  && cond->__data.__woken_seq < val)
+	break;
+    }
+
+  /* Another thread woken up.  */
+  ++cond->__data.__woken_seq;
+
+  /* We are done with the condvar.  */
+  lll_mutex_unlock (cond->__data.__lock);
+
+  /* The cancellation handling is back to normal, remove the handler.  */
+  __pthread_cleanup_pop (&buffer, 0);
+
+  /* Get the mutex before returning.  */
+  __pthread_mutex_lock_internal (mutex);
+
+  return 0;
+}
+
+versioned_symbol (libpthread, __pthread_cond_wait, pthread_cond_wait,
+		  GLIBC_2_3_2);