[glibc] Add AT_HANDLE_FID from Linux 6.5 to bits/fcntl-linux.h

[glibc] Add AT_HANDLE_FID from Linux 6.5 to bits/fcntl-linux.h

[Joseph Myers]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=2399ab0d2076b485aa81855e048a7a44d3c12eaa

commit 2399ab0d2076b485aa81855e048a7a44d3c12eaa
Author: Joseph Myers <joseph@codesourcery.com>
Date:   Mon Oct 16 13:18:51 2023 +0000

    Add AT_HANDLE_FID from Linux 6.5 to bits/fcntl-linux.h
    
    Linux 6.5 adds a constant AT_HANDLE_FID; add it to glibc.  Because
    this is a flag for the function name_to_handle_at declared in
    bits/fcntl-linux.h, put the flag there rather than alongside other
    AT_* flags in (OS-independent) fcntl.h.
    
    Tested for x86_64.

Diff:
---
 sysdeps/unix/sysv/linux/bits/fcntl-linux.h | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/sysdeps/unix/sysv/linux/bits/fcntl-linux.h b/sysdeps/unix/sysv/linux/bits/fcntl-linux.h
index df378c7b89..dd9d9baf09 100644
--- a/sysdeps/unix/sysv/linux/bits/fcntl-linux.h
+++ b/sysdeps/unix/sysv/linux/bits/fcntl-linux.h
@@ -368,6 +368,17 @@ struct file_handle
 # define MAX_HANDLE_SZ	128
 #endif
 
+#ifdef __USE_GNU
+/* Flags for name_to_handle_at.  See comment in fcntl.h about the use
+   of the same AT_* flag bits for different purposes in different
+   functions.  */
+# define AT_HANDLE_FID		AT_REMOVEDIR /* File handle is needed
+						to compare object
+						identity and may not
+						be usable to
+						open_by_handle_at.  */
+#endif
+
 __BEGIN_DECLS
 
 #ifdef __USE_GNU