Add Linux/macOS compatibility system headers to tools/build/cross-build

These headers are required in order to build the bootstrap tools on macOS
and Linux. A follow-up commit will add implementations of functions that
don't exist on those operating systems to -legacy when bootstrapping.

Reviewed By:	brooks
Differential Revision: https://reviews.freebsd.org/D14316

1 files changed, 278 insertions, 0 deletions

diff --git a/tools/build/cross-build/include/common/sys/cdefs.h b/tools/build/cross-build/include/common/sys/cdefs.h
new file mode 100644
index 000000000000..6114fcbb9638
--- /dev/null
+++ b/tools/build/cross-build/include/common/sys/cdefs.h
@@ -0,0 +1,278 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright 2018-2020 Alex Richardson <arichardson@FreeBSD.org>
+ *
+ * This software was developed by SRI International and the University of
+ * Cambridge Computer Laboratory (Department of Computer Science and
+ * Technology) under DARPA contract HR0011-18-C-0016 ("ECATS"), as part of the
+ * DARPA SSITH research programme.
+ *
+ * This software was developed by SRI International and the University of
+ * Cambridge Computer Laboratory under DARPA/AFRL contract (FA8750-10-C-0237)
+ * ("CTSRD"), as part of the DARPA CRASH research programme.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+#pragma once
+/* musl libc does not provide a sys/cdefs.h header */
+#if __has_include_next(<sys/cdefs.h>)
+#include_next <sys/cdefs.h>
+#else
+/* No sys/cdefs.h header exists so we have to provide some basic macros */
+#ifdef __cplusplus
+#define __BEGIN_DECLS extern "C" {
+#define __END_DECLS }
+#else
+#define __BEGIN_DECLS
+#define __END_DECLS
+#endif
+
+#endif
+
+#ifndef __FBSDID
+#define __FBSDID(id)
+#endif
+
+#ifndef __IDSTRING
+#define __IDSTRING(name, string)
+#endif
+
+#ifndef rounddown
+#define rounddown(x, y) (((x) / (y)) * (y))
+#define rounddown2(x, y) ((x) & (~((y)-1))) /* if y is power of two */
+#define roundup(x, y) ((((x) + ((y)-1)) / (y)) * (y)) /* to any y */
+#define roundup2(x, y) \
+	(((x) + ((y)-1)) & (~((y)-1))) /* if y is powers of two */
+#define powerof2(x) ((((x)-1) & (x)) == 0)
+#endif
+
+#ifndef __pure
+#define __pure __attribute__((__pure__))
+#endif
+#ifndef __packed
+#define __packed __attribute__((__packed__))
+#endif
+#ifndef __dead2
+#define __dead2 __attribute__((__noreturn__))
+#endif
+#ifndef __pure2
+#define __pure2 __attribute__((__const__))
+#endif
+#ifndef __used
+#define __used __attribute__((__used__))
+#endif
+#ifndef __aligned
+#define __aligned(x) __attribute__((__aligned__(x)))
+#endif
+#ifndef __section
+#define __section(x) __attribute__((__section__(x)))
+#endif
+
+#ifndef __alloc_size
+#define __alloc_size(...) __attribute__((__alloc_size__(__VA_ARGS__)))
+#endif
+#ifndef __alloc_size2
+#define __alloc_size2(n, x) __attribute__((__alloc_size__(n, x)))
+#endif
+#ifndef __alloc_align
+#define __alloc_align(x) __attribute__((__alloc_align__(x)))
+#endif
+#ifndef __result_use_check
+#define __result_use_check __attribute__((__warn_unused_result__))
+#endif
+#ifndef __printflike
+#define __printflike(fmtarg, firstvararg) \
+	__attribute__((__format__(__printf__, fmtarg, firstvararg)))
+#endif
+#ifndef __printf0like
+#define __printf0like(fmtarg, firstvararg) \
+	__attribute__((__format__(__printf0__, fmtarg, firstvararg)))
+#endif
+
+#ifndef __predict_true
+#define __predict_true(exp) __builtin_expect((exp), 1)
+#endif
+#ifndef __predict_false
+#define __predict_false(exp) __builtin_expect((exp), 0)
+#endif
+
+#ifndef __weak_reference
+#ifdef __ELF__
+#define __weak_reference(sym, alias) \
+	__asm__(".weak " #alias);    \
+	__asm__(".equ " #alias ", " #sym)
+#else
+#define __weak_reference(sym, alias) \
+	static int alias() __attribute__((weakref(#sym)));
+#endif
+#endif
+
+/* Some files built as part of the bootstrap libegacy use these macros, but
+ * since we aren't actually building libc.so, we can defined them to be empty */
+#ifndef __sym_compat
+#define __sym_compat(sym, impl, verid) /* not needed for bootstrapping */
+#endif
+#ifndef __sym_default
+#define __sym_default(sym, impl, verid) /* not needed for bootstrapping */
+#endif
+#ifndef __sym_default
+#define __warn_references(sym, msg) /* not needed for bootstrapping */
+#endif
+
+#ifndef __malloc_like
+#define __malloc_like __attribute__((__malloc__))
+#endif
+
+#ifndef nitems
+// https://stackoverflow.com/questions/1598773/is-there-a-standard-function-in-c-that-would-return-the-length-of-an-array/1598827#1598827
+#define nitems(x) \
+	((sizeof(x) / sizeof(0 [x])) / ((size_t)(!(sizeof(x) % sizeof(0 [x])))))
+#endif
+
+#ifndef __min_size
+#if !defined(__cplusplus)
+#define __min_size(x) static(x)
+#else
+#define __min_size(x) (x)
+#endif
+#endif
+
+#ifndef __unused
+#define __unused __attribute__((unused))
+#endif
+#define __format_arg(fmtarg) __attribute__((__format_arg__(fmtarg)))
+
+#ifndef __exported
+#define __exported __attribute__((__visibility__("default")))
+#endif
+#ifndef __hidden
+#define __hidden __attribute__((__visibility__("hidden")))
+#endif
+
+#ifndef __unreachable
+#define __unreachable() __builtin_unreachable()
+#endif
+
+#ifndef __clang__
+/* GCC doesn't like the printf0 format specifier. Clang treats it the same as
+ * printf so add the compatibility macro here. */
+#define __printf0__ __printf__
+#endif
+
+/*
+ * These should probably be in sys/types.h but mtree expects them to exist
+ * without including <sys/types.h>
+ */
+typedef unsigned char u_char;
+typedef unsigned short u_short;
+typedef unsigned int u_int;
+typedef unsigned long u_long;
+
+/* This is needed so that BSNMP doesn't redeclare an incompatible version */
+#define HAVE_STRLCPY 1
+/* The compiler supports __func__ */
+#define HAVE_DECL___FUNC__ 1
+
+/* On MacOS __CONCAT is defined as x ## y, which won't expand macros */
+#undef __CONCAT
+#define __CONCAT1(x, y) x##y
+#define __CONCAT(x, y) __CONCAT1(x, y)
+
+#ifndef __STRING
+#define __STRING(x) #x /* stringify without expanding x */
+#endif
+#ifndef __XSTRING
+#define __XSTRING(x) __STRING(x) /* expand x, then stringify */
+#endif
+
+#ifndef __has_feature
+#define __has_feature(...) 0
+#endif
+
+#ifndef __has_builtin
+#define __has_builtin(...) 0
+#endif
+
+/*
+ * Nullability qualifiers: currently only supported by Clang.
+ */
+#if !(defined(__clang__) && __has_feature(nullability))
+#define _Nonnull
+#define _Nullable
+#define _Null_unspecified
+#define __NULLABILITY_PRAGMA_PUSH
+#define __NULLABILITY_PRAGMA_POP
+#else
+#define __NULLABILITY_PRAGMA_PUSH        \
+	_Pragma("clang diagnostic push") \
+	    _Pragma("clang diagnostic ignored \"-Wnullability-completeness\"")
+#define __NULLABILITY_PRAGMA_POP _Pragma("clang diagnostic pop")
+#endif
+
+#ifndef __offsetof
+#define __offsetof(type, field) __builtin_offsetof(type, field)
+#endif
+
+#define __rangeof(type, start, end) \
+	(__offsetof(type, end) - __offsetof(type, start))
+
+#ifndef __containerof
+#define __containerof(x, s, m)                                           \
+	({                                                               \
+		const volatile __typeof(((s *)0)->m) *__x = (x);         \
+		__DEQUALIFY(                                             \
+		    s *, (const volatile char *)__x - __offsetof(s, m)); \
+	})
+#endif
+
+#ifndef __RCSID
+#define __RCSID(x)
+#endif
+#ifndef __FBSDID
+#define __FBSDID(x)
+#endif
+#ifndef __RCSID
+#define __RCSID(x)
+#endif
+#ifndef __RCSID_SOURCE
+#define __RCSID_SOURCE(x)
+#endif
+#ifndef __SCCSID
+#define __SCCSID(x)
+#endif
+#ifndef __COPYRIGHT
+#define __COPYRIGHT(x)
+#endif
+#ifndef __DECONST
+#define __DECONST(type, var) ((type)(__uintptr_t)(const void *)(var))
+#endif
+
+#ifndef __DEVOLATILE
+#define __DEVOLATILE(type, var) ((type)(__uintptr_t)(volatile void *)(var))
+#endif
+
+#ifndef __DEQUALIFY
+#define __DEQUALIFY(type, var) ((type)(__uintptr_t)(const volatile void *)(var))
+#endif