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
bpf_num_possible_cpus(void)11 static 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 */
bpf_strlcpy(char * dst,const char * src,size_t sz)29 static 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