From 5f798d38e967c62cca40c99bfc3e9c5ca0f37540 Mon Sep 17 00:00:00 2001 From: Joe Simmons-Talbott Date: Mon, 11 Sep 2023 16:16:49 +0000 Subject: stdio: Remove __libc_message alloca usage Use a fixed size array instead. The maximum number of arguments is set by macro tricks. Co-authored-by: Adhemerval Zanella Reviewed-by: Adhemerval Zanella --- include/stdio.h | 29 ++++++++++++++++++++++++++++- 1 file changed, 28 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/stdio.h b/include/stdio.h index 6755877911..7e70f95c6d 100644 --- a/include/stdio.h +++ b/include/stdio.h @@ -172,10 +172,37 @@ extern int __gen_tempname (char *__tmpl, int __suffixlen, int __flags, and abort. */ extern void __libc_fatal (const char *__message) __attribute__ ((__noreturn__)); -_Noreturn void __libc_message (const char *__fnt, ...) attribute_hidden; extern void __fortify_fail (const char *msg) __attribute__ ((__noreturn__)); libc_hidden_proto (__fortify_fail) +/* The maximum number of varargs allowed in a __libc_message format string */ +#define LIBC_MESSAGE_MAX_ARGS 4 + +_Noreturn void __libc_message_impl (const char *__fnt, ...) attribute_hidden + __attribute__ ((__format__ (__printf__, 1, 2))); + +#define __libc_message0(fmt) \ + __libc_message_impl (fmt) +#define __libc_message1(fmt, a1) \ + __libc_message_impl (fmt, a1) +#define __libc_message2(fmt, a1, a2) \ + __libc_message_impl (fmt, a1, a2) +#define __libc_message3(fmt, a1, a2, a3) \ + __libc_message_impl (fmt, a1, a2, a3) +#define __libc_message4(fmt, a1, a2, a3, a4) \ + __libc_message_impl (fmt, a1, a2, a3, a4) + +#define __libc_message_concat_x(a,b) a##b +#define __libc_message_concat(a,b) __libc_message_concat_x (a, b) + +#define __libc_message_nargs_x(a0,a1,a2,a3,a4,a5,a6,...) a6 +#define __libc_message_nargs(b, ...) \ + __libc_message_nargs_x (__VA_ARGS__,6,5,4,3,2,1,0,) +#define __libc_message_disp(b, ...) \ + __libc_message_concat (b, __libc_message_nargs (__VA_ARGS__))(__VA_ARGS__) +#define __libc_message(...) \ + __libc_message_disp (__libc_message, __VA_ARGS__) + /* Acquire ownership of STREAM. */ extern void __flockfile (FILE *__stream) attribute_hidden; -- cgit 1.4.1