1 // SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) 2 3 /* 4 * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org> 5 * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com> 6 * Copyright (C) 2015 Huawei Inc. 7 * Copyright (C) 2017 Nicira, Inc. 8 */ 9 10 #undef _GNU_SOURCE 11 #include <stdio.h> 12 #include <string.h> 13 14 #include "libbpf.h" 15 #include "libbpf_internal.h" 16 17 /* make sure libbpf doesn't use kernel-only integer typedefs */ 18 #pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64 19 20 #define ERRNO_OFFSET(e) ((e) - __LIBBPF_ERRNO__START) 21 #define ERRCODE_OFFSET(c) ERRNO_OFFSET(LIBBPF_ERRNO__##c) 22 #define NR_ERRNO (__LIBBPF_ERRNO__END - __LIBBPF_ERRNO__START) 23 24 static const char *libbpf_strerror_table[NR_ERRNO] = { 25 [ERRCODE_OFFSET(LIBELF)] = "Something wrong in libelf", 26 [ERRCODE_OFFSET(FORMAT)] = "BPF object format invalid", 27 [ERRCODE_OFFSET(KVERSION)] = "'version' section incorrect or lost", 28 [ERRCODE_OFFSET(ENDIAN)] = "Endian mismatch", 29 [ERRCODE_OFFSET(INTERNAL)] = "Internal error in libbpf", 30 [ERRCODE_OFFSET(RELOC)] = "Relocation failed", 31 [ERRCODE_OFFSET(VERIFY)] = "Kernel verifier blocks program loading", 32 [ERRCODE_OFFSET(PROG2BIG)] = "Program too big", 33 [ERRCODE_OFFSET(KVER)] = "Incorrect kernel version", 34 [ERRCODE_OFFSET(PROGTYPE)] = "Kernel doesn't support this program type", 35 [ERRCODE_OFFSET(WRNGPID)] = "Wrong pid in netlink message", 36 [ERRCODE_OFFSET(INVSEQ)] = "Invalid netlink sequence", 37 [ERRCODE_OFFSET(NLPARSE)] = "Incorrect netlink message parsing", 38 }; 39 libbpf_strerror(int err,char * buf,size_t size)40 int libbpf_strerror(int err, char *buf, size_t size) 41 { 42 int ret; 43 44 if (!buf || !size) 45 return libbpf_err(-EINVAL); 46 47 err = err > 0 ? err : -err; 48 49 if (err < __LIBBPF_ERRNO__START) { 50 ret = strerror_r(err, buf, size); 51 buf[size - 1] = '\0'; 52 return libbpf_err_errno(ret); 53 } 54 55 if (err < __LIBBPF_ERRNO__END) { 56 const char *msg; 57 58 msg = libbpf_strerror_table[ERRNO_OFFSET(err)]; 59 ret = snprintf(buf, size, "%s", msg); 60 buf[size - 1] = '\0'; 61 /* The length of the buf and msg is positive. 62 * A negative number may be returned only when the 63 * size exceeds INT_MAX. Not likely to appear. 64 */ 65 if (ret >= size) 66 return libbpf_err(-ERANGE); 67 return 0; 68 } 69 70 ret = snprintf(buf, size, "Unknown libbpf error %d", err); 71 buf[size - 1] = '\0'; 72 if (ret >= size) 73 return libbpf_err(-ERANGE); 74 return libbpf_err(-ENOENT); 75 } 76