linux-stable/tools/lib/bpf/libbpf_errno.c
Andrii Nakryiko 1d1a3bcffe libbpf: Poison kernel-only integer types
It's been a recurring issue with types like u32 slipping into libbpf source
code accidentally. This is not detected during builds inside kernel source
tree, but becomes a compilation error in libbpf's Github repo. Libbpf is
supposed to use only __{s,u}{8,16,32,64} typedefs, so poison {s,u}{8,16,32,64}
explicitly in every .c file. Doing that in a bit more centralized way, e.g.,
inside libbpf_internal.h breaks selftests, which are both using kernel u32 and
libbpf_internal.h.

This patch also fixes a new u32 occurence in libbpf.c, added recently.

Fixes: 590a008882 ("bpf: libbpf: Add STRUCT_OPS support")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200110181916.271446-1-andriin@fb.com
2020-01-10 10:38:00 -08:00

66 lines
1.9 KiB
C

// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
/*
* Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org>
* Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
* Copyright (C) 2015 Huawei Inc.
* Copyright (C) 2017 Nicira, Inc.
*/
#undef _GNU_SOURCE
#include <stdio.h>
#include <string.h>
#include "libbpf.h"
/* make sure libbpf doesn't use kernel-only integer typedefs */
#pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
#define ERRNO_OFFSET(e) ((e) - __LIBBPF_ERRNO__START)
#define ERRCODE_OFFSET(c) ERRNO_OFFSET(LIBBPF_ERRNO__##c)
#define NR_ERRNO (__LIBBPF_ERRNO__END - __LIBBPF_ERRNO__START)
static const char *libbpf_strerror_table[NR_ERRNO] = {
[ERRCODE_OFFSET(LIBELF)] = "Something wrong in libelf",
[ERRCODE_OFFSET(FORMAT)] = "BPF object format invalid",
[ERRCODE_OFFSET(KVERSION)] = "'version' section incorrect or lost",
[ERRCODE_OFFSET(ENDIAN)] = "Endian mismatch",
[ERRCODE_OFFSET(INTERNAL)] = "Internal error in libbpf",
[ERRCODE_OFFSET(RELOC)] = "Relocation failed",
[ERRCODE_OFFSET(VERIFY)] = "Kernel verifier blocks program loading",
[ERRCODE_OFFSET(PROG2BIG)] = "Program too big",
[ERRCODE_OFFSET(KVER)] = "Incorrect kernel version",
[ERRCODE_OFFSET(PROGTYPE)] = "Kernel doesn't support this program type",
[ERRCODE_OFFSET(WRNGPID)] = "Wrong pid in netlink message",
[ERRCODE_OFFSET(INVSEQ)] = "Invalid netlink sequence",
[ERRCODE_OFFSET(NLPARSE)] = "Incorrect netlink message parsing",
};
int libbpf_strerror(int err, char *buf, size_t size)
{
if (!buf || !size)
return -1;
err = err > 0 ? err : -err;
if (err < __LIBBPF_ERRNO__START) {
int ret;
ret = strerror_r(err, buf, size);
buf[size - 1] = '\0';
return ret;
}
if (err < __LIBBPF_ERRNO__END) {
const char *msg;
msg = libbpf_strerror_table[ERRNO_OFFSET(err)];
snprintf(buf, size, "%s", msg);
buf[size - 1] = '\0';
return 0;
}
snprintf(buf, size, "Unknown libbpf error %d", err);
buf[size - 1] = '\0';
return -1;
}