tools/testing/selftests/filesystems/openat2/helpers.h

Source file repositories/reference/linux-study-clean/tools/testing/selftests/filesystems/openat2/helpers.h

File Facts

System
Linux kernel
Corpus path
tools/testing/selftests/filesystems/openat2/helpers.h
Extension
.h
Size
2874 bytes
Lines
136
Domain
Support Tooling And Documentation
Bucket
tools
Inferred role
Support Tooling And Documentation: implementation source
Status
source implementation candidate

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Author: Aleksa Sarai <cyphar@cyphar.com>
 * Copyright (C) 2018-2019 SUSE LLC.
 * Copyright (C) 2026 Amutable GmbH
 */

#ifndef __RESOLVEAT_H__
#define __RESOLVEAT_H__

#define _GNU_SOURCE
#include <stdint.h>
#include <stdbool.h>
#include <errno.h>
#include <limits.h>
#include <linux/types.h>
#include <linux/unistd.h>
#include <linux/openat2.h>
#include "kselftest_harness.h"

#define BUILD_BUG_ON(e) ((void)(sizeof(struct { int:(-!!(e)); })))

#define OPEN_HOW_SIZE_VER0	24 /* sizeof first published struct */
#define OPEN_HOW_SIZE_LATEST	OPEN_HOW_SIZE_VER0

__maybe_unused
static bool needs_openat2(const struct open_how *how)
{
	return how->resolve != 0;
}

__maybe_unused
static int raw_openat2(int dfd, const char *path, void *how, size_t size)
{
	int ret = syscall(__NR_openat2, dfd, path, how, size);

	return ret >= 0 ? ret : -errno;
}

__maybe_unused
static int sys_openat2(int dfd, const char *path, struct open_how *how)
{
	return raw_openat2(dfd, path, how, sizeof(*how));
}

__maybe_unused
static int sys_openat(int dfd, const char *path, struct open_how *how)
{
	int ret = openat(dfd, path, how->flags, how->mode);

	return ret >= 0 ? ret : -errno;
}

__maybe_unused
static int sys_renameat2(int olddirfd, const char *oldpath,
			 int newdirfd, const char *newpath, unsigned int flags)
{
	int ret = syscall(__NR_renameat2, olddirfd, oldpath,
					  newdirfd, newpath, flags);

	return ret >= 0 ? ret : -errno;
}

__maybe_unused
static int touchat(int dfd, const char *path)
{
	int fd = openat(dfd, path, O_CREAT, 0700);

	if (fd >= 0)
		close(fd);
	return fd;
}

__maybe_unused
static char *fdreadlink(struct __test_metadata *_metadata, int fd)
{
	char *target, *tmp;

	ASSERT_GT(asprintf(&tmp, "/proc/self/fd/%d", fd), 0);

	target = malloc(PATH_MAX);
	ASSERT_NE(target, NULL);
	memset(target, 0, PATH_MAX);

	ASSERT_GT(readlink(tmp, target, PATH_MAX), 0);

	free(tmp);
	return target;
}

Annotation

Implementation Notes