These macros take the end of the array argument implicitly to avoid
programmer mistakes.  This guarantees that the input is an array, unlike

	snprintf(buf, sizeof(buf), ...);

which is dangerous if the programmer passes a pointer instead of an
array.

These macros are essentially the same as the 2-argument version of
strscpy(), but with a formatted string.

Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Marco Elver <elver@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
---
 include/linux/sprintf.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/include/linux/sprintf.h b/include/linux/sprintf.h
index 8dfc37713747..bd8174224a4a 100644
--- a/include/linux/sprintf.h
+++ b/include/linux/sprintf.h
@@ -4,6 +4,10 @@
 
 #include <linux/compiler_attributes.h>
 #include <linux/types.h>
+#include <linux/array_size.h>
+
+#define sprintf_array(a, fmt, ...)  sprintf_trunc(a, ARRAY_SIZE(a), fmt, ##__VA_ARGS__)
+#define vsprintf_array(a, fmt, ap)  vsprintf_trunc(a, ARRAY_SIZE(a), fmt, ap)
 
 int num_to_str(char *buf, int size, unsigned long long num, unsigned int width);
 
-- 
2.50.0