LXR linux/tools/lib/bpf/libbpf

   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
  24static 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
  40int libbpf_strerror(int err, char *buf, size_t size)
  41{
  42        if (!buf || !size)
  43                return libbpf_err(-EINVAL);
  44
  45        err = err > 0 ? err : -err;
  46
  47        if (err < __LIBBPF_ERRNO__START) {
  48                int ret;
  49
  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                snprintf(buf, size, "%s", msg);
  60                buf[size - 1] = '\0';
  61                return 0;
  62        }
  63
  64        snprintf(buf, size, "Unknown libbpf error %d", err);
  65        buf[size - 1] = '\0';
  66        return libbpf_err(-ENOENT);
  67}
  68