Fix F_GETOWN on some Linux archs.

The syscall conventions on some Linux archs prevented F_GETOWN from working
correctly in some situations.  This can be rectified when using the new
F_GETOWN_EX command.

1 files changed, 38 insertions, 4 deletions

diff --git a/sysdeps/unix/sysv/linux/fcntl.c b/sysdeps/unix/sysv/linux/fcntl.c
index 1f5aca1..b19654c 100644
--- a/sysdeps/unix/sysv/linux/fcntl.c
+++ b/sysdeps/unix/sysv/linux/fcntl.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2000, 2002, 2003, 2004 Free Software Foundation, Inc.
+/* Copyright (C) 2000, 2002, 2003, 2004, 2009 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -23,6 +23,40 @@
 #include <stdarg.h>
 
 #include <sys/syscall.h>
+#include <kernel-features.h>
+
+
+#ifdef __ASSUME_F_GETOWN_EX
+# define miss_F_GETOWN_EX 0
+#else
+static int miss_F_GETOWN_EX;
+#endif
+
+
+static int
+do_fcntl (int fd, int cmd, void *arg)
+{
+  if (cmd != F_GETOWN || miss_F_GETOWN_EX)
+    return INLINE_SYSCALL (fcntl, 3, fd, cmd, arg);
+
+  INTERNAL_SYSCALL_DECL (err);
+  struct f_owner_ex fex;
+  int res = INTERNAL_SYSCALL (fcntl, err, 3, fd, F_GETOWN_EX, &fex);
+  if (!INTERNAL_SYSCALL_ERROR_P (res, err))
+    return fex.type == F_OWNER_GID ? -fex.pid : fex.pid;
+
+#ifndef __ASSUME_F_GETOWN_EX
+  if (INTERNAL_SYSCALL_ERRNO (res, err) == EINVAL)
+    {
+      res = INLINE_SYSCALL (fcntl, 3, fd, F_GETOWN, arg);
+      miss_F_GETOWN_EX = 1;
+      return res;
+    }
+#endif
+
+  __set_errno (INTERNAL_SYSCALL_ERRNO (res, err));
+  return -1;
+}
 
 
 #ifndef NO_CANCELLATION
@@ -36,7 +70,7 @@ __fcntl_nocancel (int fd, int cmd, ...)
   arg = va_arg (ap, void *);
   va_end (ap);
 
-  return INLINE_SYSCALL (fcntl, 3, fd, cmd, arg);
+  return do_fcntl (fd, cmd, arg);
 }
 #endif
 
@@ -52,11 +86,11 @@ __libc_fcntl (int fd, int cmd, ...)
   va_end (ap);
 
   if (SINGLE_THREAD_P || cmd != F_SETLKW)
-    return INLINE_SYSCALL (fcntl, 3, fd, cmd, arg);
+    return do_fcntl (fd, cmd, arg);
 
   int oldtype = LIBC_CANCEL_ASYNC ();
 
-  int result = INLINE_SYSCALL (fcntl, 3, fd, cmd, arg);
+  int result = do_fcntl (fd, cmd, arg);
 
   LIBC_CANCEL_RESET (oldtype);