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 <syscall.h> 10 #include <bpf/libbpf.h> /* libbpf_num_possible_cpus */ 11 12 static inline unsigned int bpf_num_possible_cpus(void) 13 { 14 int possible_cpus = libbpf_num_possible_cpus(); 15 16 if (possible_cpus < 0) { 17 printf("Failed to get # of possible cpus: '%s'!\n", 18 strerror(-possible_cpus)); 19 exit(1); 20 } 21 return possible_cpus; 22 } 23 24 /* Copy up to sz - 1 bytes from zero-terminated src string and ensure that dst 25 * is zero-terminated string no matter what (unless sz == 0, in which case 26 * it's a no-op). It's conceptually close to FreeBSD's strlcpy(), but differs 27 * in what is returned. Given this is internal helper, it's trivial to extend 28 * this, when necessary. Use this instead of strncpy inside libbpf source code. 29 */ 30 static inline void bpf_strlcpy(char *dst, const char *src, size_t sz) 31 { 32 size_t i; 33 34 if (sz == 0) 35 return; 36 37 sz--; 38 for (i = 0; i < sz && src[i]; i++) 39 dst[i] = src[i]; 40 dst[i] = '\0'; 41 } 42 43 #define __bpf_percpu_val_align __attribute__((__aligned__(8))) 44 45 #define BPF_DECLARE_PERCPU(type, name) \ 46 struct { type v; /* padding */ } __bpf_percpu_val_align \ 47 name[bpf_num_possible_cpus()] 48 #define bpf_percpu(name, cpu) name[(cpu)].v 49 50 #ifndef ARRAY_SIZE 51 # define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) 52 #endif 53 54 #ifndef sizeof_field 55 #define sizeof_field(TYPE, MEMBER) sizeof((((TYPE *)0)->MEMBER)) 56 #endif 57 58 #ifndef offsetofend 59 #define offsetofend(TYPE, MEMBER) \ 60 (offsetof(TYPE, MEMBER) + sizeof_field(TYPE, MEMBER)) 61 #endif 62 63 /* Availability of gettid across glibc versions is hit-and-miss, therefore 64 * fallback to syscall in this macro and use it everywhere. 65 */ 66 #ifndef sys_gettid 67 #define sys_gettid() syscall(SYS_gettid) 68 #endif 69 70 #ifndef ENOTSUPP 71 #define ENOTSUPP 524 72 #endif 73 74 #endif /* __BPF_UTIL__ */ 75