This allows nolic to work with `-nostdinc` avoiding any reliance on system headers.
The implementation has been lifted from musl libc 1.2.4. There is already an implementation of stdarg.h in include/linux/stdarg.h but that is GPL licensed and therefore not suitable for nolibc.
The used compiler builtins have been validated to be at least available since GCC 4.1.2 and clang 3.0.0.
Signed-off-by: Thomas Weißschuh linux@weissschuh.net --- tools/include/nolibc/Makefile | 1 + tools/include/nolibc/nolibc.h | 4 ++-- tools/include/nolibc/stdarg.h | 16 ++++++++++++++++ tools/include/nolibc/stdio.h | 3 +-- tools/include/nolibc/sys.h | 2 +- 5 files changed, 21 insertions(+), 5 deletions(-)
diff --git a/tools/include/nolibc/Makefile b/tools/include/nolibc/Makefile index 909b6eb500fe..e69c26abe1ea 100644 --- a/tools/include/nolibc/Makefile +++ b/tools/include/nolibc/Makefile @@ -34,6 +34,7 @@ all_files := \ signal.h \ stackprotector.h \ std.h \ + stdarg.h \ stdint.h \ stdlib.h \ string.h \ diff --git a/tools/include/nolibc/nolibc.h b/tools/include/nolibc/nolibc.h index 1f8d821000ac..989e707263a4 100644 --- a/tools/include/nolibc/nolibc.h +++ b/tools/include/nolibc/nolibc.h @@ -74,10 +74,10 @@ * -I../nolibc -o hello hello.c -lgcc * * The available standard (but limited) include files are: - * ctype.h, errno.h, signal.h, stdio.h, stdlib.h, string.h, time.h + * ctype.h, errno.h, signal.h, stdarg.h, stdio.h, stdlib.h, string.h, time.h * * In addition, the following ones are expected to be provided by the compiler: - * float.h, stdarg.h, stddef.h + * float.h, stddef.h * * The following ones which are part to the C standard are not provided: * assert.h, locale.h, math.h, setjmp.h, limits.h diff --git a/tools/include/nolibc/stdarg.h b/tools/include/nolibc/stdarg.h new file mode 100644 index 000000000000..c628b5783da6 --- /dev/null +++ b/tools/include/nolibc/stdarg.h @@ -0,0 +1,16 @@ +/* SPDX-License-Identifier: LGPL-2.1 OR MIT */ +/* + * Variadic argument support for NOLIBC + * Copyright (C) 2005-2020 Rich Felker, et al. + */ + +#ifndef _NOLIBC_STDARG_H +#define _NOLIBC_STDARG_H + +typedef __builtin_va_list va_list; +#define va_start(v, l) __builtin_va_start(v, l) +#define va_end(v) __builtin_va_end(v) +#define va_arg(v, l) __builtin_va_arg(v, l) +#define va_copy(d, s) __builtin_va_copy(d, s) + +#endif /* _NOLIBC_STDARG_H */ diff --git a/tools/include/nolibc/stdio.h b/tools/include/nolibc/stdio.h index cae402c11e57..d7ef43973916 100644 --- a/tools/include/nolibc/stdio.h +++ b/tools/include/nolibc/stdio.h @@ -7,13 +7,12 @@ #ifndef _NOLIBC_STDIO_H #define _NOLIBC_STDIO_H
-#include <stdarg.h> - #include "std.h" #include "arch.h" #include "errno.h" #include "types.h" #include "sys.h" +#include "stdarg.h" #include "stdlib.h" #include "string.h"
diff --git a/tools/include/nolibc/sys.h b/tools/include/nolibc/sys.h index fdb6bd6c0e2f..b478750c9004 100644 --- a/tools/include/nolibc/sys.h +++ b/tools/include/nolibc/sys.h @@ -7,7 +7,6 @@ #ifndef _NOLIBC_SYS_H #define _NOLIBC_SYS_H
-#include <stdarg.h> #include "std.h"
/* system includes */ @@ -25,6 +24,7 @@
#include "arch.h" #include "errno.h" +#include "stdarg.h" #include "types.h"