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 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 */ 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