* semaphoreP.h: Declare __old_sem_init and __old_sem_wait.

	* sem_init.c (__new_sem_init): Rewrite to initialize all three
	fields in the structure.
	(__old_sem_init): New function.
	* sem_open.c: Initialize all fields of the structure.
	* sem_getvalue.c: Adjust for renamed element.
	* sysdeps/unix/sysv/linux/Makefile [subdir=nptl]
	(gen-as-const-headers): Add structsem.sym.
	* sysdeps/unix/sysv/linux/structsem.sym: New file.
	* sysdeps/unix/sysv/linux/internaltypes.h: Rename struct sem to
	struct new_sem.  Add struct old_sem.
	* sysdeps/unix/sysv/linux/sem_post.c: Wake only when there are waiters.
	* sysdeps/unix/sysv/linux/i386/i486/sem_post.S: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/sem_post.S: Likewise.
	* sysdeps/unix/sysv/linux/sem_wait.c: Indicate that there are waiters.
	* sysdeps/unix/sysv/linux/i386/i486/sem_wait.S: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/sem_wait.S: Likewise.
	* sysdeps/unix/sysv/linux/sem_timedwait.c: Likewise.
	* sysdeps/unix/sysv/linux/i386/i486/sem_timedwait.S: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/sem_timedwait.S: Likewise.
	* Makefile (tests): Add tst-sem10, tst-sem11, tst-sem12.
	* tst-sem10.c: New file.
	* tst-sem11.c: New file.
	* tst-sem12.c: New file.
	* tst-typesizes.c: Test struct new_sem and struct old_sem instead
	of struct sem.

2007-05-25  Ulrich Drepper  <drepper@redhat.com>

1 files changed, 57 insertions, 3 deletions

diff --git a/nptl/sysdeps/unix/sysv/linux/sem_wait.c b/nptl/sysdeps/unix/sysv/linux/sem_wait.c
index d1aa97571a..e35b6480f2 100644
--- a/nptl/sysdeps/unix/sysv/linux/sem_wait.c
+++ b/nptl/sysdeps/unix/sysv/linux/sem_wait.c
@@ -28,9 +28,66 @@
 #include <shlib-compat.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)
 {
+  struct new_sem *isem = (struct new_sem *) sem;
+  int err;
+
+  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 (&isem->value, 0);
+
+      /* Disable asynchronous cancellation.  */
+      __pthread_disable_asynccancel (oldtype);
+
+      if (err != 0 && err != -EWOULDBLOCK)
+	{
+	  __set_errno (-err);
+	  err = -1;
+	}
+
+      if (atomic_decrement_if_positive (&isem->value) > 0)
+	{
+	  err = 0;
+	  break;
+	}
+    }
+
+  pthread_cleanup_pop (0);
+
+  atomic_decrement (&isem->nwaiters);
+
+  return err;
+}
+versioned_symbol (libpthread, __new_sem_wait, sem_wait, GLIBC_2_1);
+
+
+#if SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_1)
+int
+attribute_compat_text_section
+__old_sem_wait (sem_t *sem)
+{
   int *futex = (int *) sem;
   int err;
 
@@ -53,8 +110,5 @@ __new_sem_wait (sem_t *sem)
   return -1;
 }
 
-versioned_symbol (libpthread, __new_sem_wait, sem_wait, GLIBC_2_1);
-#if SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_1)
-strong_alias (__new_sem_wait, __old_sem_wait)
 compat_symbol (libpthread, __old_sem_wait, sem_wait, GLIBC_2_0);
 #endif