user: implement mlibc as the libc, finally.

It's finally done..

Signed-off-by: kaguya <vpshinomiya@protonmail.com>

ext2_root/usr/include/printf.h

@@ -0,0 +1,41 @@
+#ifndef  _PRINTF_H
+#define  _PRINTF_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stddef.h>
+#include <stdarg.h>
+
+#ifndef __MLIBC_ABI_ONLY
+
+/* This seems to be a glibc thing, so constants are from glibc */
+size_t parse_printf_format(const char * __restrict __format, size_t __size, int * __restrict __argtypes);
+
+#endif /* !__MLIBC_ABI_ONLY */
+
+enum {
+	PA_INT,
+	PA_CHAR,
+	PA_WCHAR,
+	PA_STRING,
+	PA_WSTRING,
+	PA_POINTER,
+	PA_FLOAT,
+	PA_DOUBLE,
+	PA_LAST
+};
+
+#define PA_FLAG_MASK			0xff00
+#define PA_FLAG_LONG_LONG		(1 << 8)
+#define PA_FLAG_LONG_DOUBLE		PA_FLAG_LONG_LONG
+#define PA_FLAG_LONG			(1 << 9)
+#define PA_FLAG_SHORT			(1 << 10)
+#define PA_FLAG_PTR				(1 << 11)
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif