1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __BPF_UTIL__
3#define __BPF_UTIL__
4
5#include <stdio.h>
6#include <stdlib.h>
7#include <string.h>
8#include <errno.h>
9#include <bpf/libbpf.h> /* libbpf_num_possible_cpus */
10
11static inline unsigned int bpf_num_possible_cpus(void)
12{
13	int possible_cpus = libbpf_num_possible_cpus();
14
15	if (possible_cpus < 0) {
16		printf("Failed to get # of possible cpus: '%s'!\n",
17		       strerror(-possible_cpus));
18		exit(1);
19	}
20	return possible_cpus;
21}
22
23/* Copy up to sz - 1 bytes from zero-terminated src string and ensure that dst
24 * is zero-terminated string no matter what (unless sz == 0, in which case
25 * it's a no-op). It's conceptually close to FreeBSD's strlcpy(), but differs
26 * in what is returned. Given this is internal helper, it's trivial to extend
27 * this, when necessary. Use this instead of strncpy inside libbpf source code.
28 */
29static inline void bpf_strlcpy(char *dst, const char *src, size_t sz)
30{
31	size_t i;
32
33	if (sz == 0)
34		return;
35
36	sz--;
37	for (i = 0; i < sz && src[i]; i++)
38		dst[i] = src[i];
39	dst[i] = '\0';
40}
41
42#define __bpf_percpu_val_align	__attribute__((__aligned__(8)))
43
44#define BPF_DECLARE_PERCPU(type, name)				\
45	struct { type v; /* padding */ } __bpf_percpu_val_align	\
46		name[bpf_num_possible_cpus()]
47#define bpf_percpu(name, cpu) name[(cpu)].v
48
49#ifndef ARRAY_SIZE
50# define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
51#endif
52
53#ifndef sizeof_field
54#define sizeof_field(TYPE, MEMBER) sizeof((((TYPE *)0)->MEMBER))
55#endif
56
57#ifndef offsetofend
58#define offsetofend(TYPE, MEMBER) \
59	(offsetof(TYPE, MEMBER)	+ sizeof_field(TYPE, MEMBER))
60#endif
61
62#endif /* __BPF_UTIL__ */
63