[PATCH 05/10] close_range: turn the flags into an enum

[Christian Brauner <brauner@kernel.org>]

Turn the close_range() flags into an enum. Makes debugging a lot easier.

No functional changes.

Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
---
 include/uapi/linux/close_range.h | 21 +++++++++++++++++----
 1 file changed, 17 insertions(+), 4 deletions(-)

diff --git a/include/uapi/linux/close_range.h b/include/uapi/linux/close_range.h
index 2d804281554c..b1b637d74deb 100644
--- a/include/uapi/linux/close_range.h
+++ b/include/uapi/linux/close_range.h
@@ -2,11 +2,24 @@
 #ifndef _UAPI_LINUX_CLOSE_RANGE_H
 #define _UAPI_LINUX_CLOSE_RANGE_H
 
-/* Unshare the file descriptor table before closing file descriptors. */
-#define CLOSE_RANGE_UNSHARE	(1U << 1)
+/*
+ * A macro of one of these names defined before this header is parsed, by
+ * a libc or by a program's own fallback, would replace the enumerator.
+ */
+#undef CLOSE_RANGE_UNSHARE
+#undef CLOSE_RANGE_CLOEXEC
 
-/* Set the FD_CLOEXEC bit instead of closing the file descriptor. */
-#define CLOSE_RANGE_CLOEXEC	(1U << 2)
+enum close_range_flags {
+	/* Unshare the file descriptor table before closing file descriptors. */
+	CLOSE_RANGE_UNSHARE	= (1U << 1),
+
+	/* Set the FD_CLOEXEC bit instead of closing the file descriptor. */
+	CLOSE_RANGE_CLOEXEC	= (1U << 2),
+};
+
+/* Keep #ifdef working and let glibc skip its own definitions. */
+#define CLOSE_RANGE_UNSHARE		CLOSE_RANGE_UNSHARE
+#define CLOSE_RANGE_CLOEXEC		CLOSE_RANGE_CLOEXEC
 
 #endif /* _UAPI_LINUX_CLOSE_RANGE_H */
 

-- 
2.53.0