xref: /openbmc/linux/tools/lib/bpf/libbpf_errno.c (revision 842ed298)
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 
16 /* make sure libbpf doesn't use kernel-only integer typedefs */
17 #pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
18 
19 #define ERRNO_OFFSET(e)		((e) - __LIBBPF_ERRNO__START)
20 #define ERRCODE_OFFSET(c)	ERRNO_OFFSET(LIBBPF_ERRNO__##c)
21 #define NR_ERRNO	(__LIBBPF_ERRNO__END - __LIBBPF_ERRNO__START)
22 
23 static const char *libbpf_strerror_table[NR_ERRNO] = {
24 	[ERRCODE_OFFSET(LIBELF)]	= "Something wrong in libelf",
25 	[ERRCODE_OFFSET(FORMAT)]	= "BPF object format invalid",
26 	[ERRCODE_OFFSET(KVERSION)]	= "'version' section incorrect or lost",
27 	[ERRCODE_OFFSET(ENDIAN)]	= "Endian mismatch",
28 	[ERRCODE_OFFSET(INTERNAL)]	= "Internal error in libbpf",
29 	[ERRCODE_OFFSET(RELOC)]		= "Relocation failed",
30 	[ERRCODE_OFFSET(VERIFY)]	= "Kernel verifier blocks program loading",
31 	[ERRCODE_OFFSET(PROG2BIG)]	= "Program too big",
32 	[ERRCODE_OFFSET(KVER)]		= "Incorrect kernel version",
33 	[ERRCODE_OFFSET(PROGTYPE)]	= "Kernel doesn't support this program type",
34 	[ERRCODE_OFFSET(WRNGPID)]	= "Wrong pid in netlink message",
35 	[ERRCODE_OFFSET(INVSEQ)]	= "Invalid netlink sequence",
36 	[ERRCODE_OFFSET(NLPARSE)]	= "Incorrect netlink message parsing",
37 };
38 
39 int libbpf_strerror(int err, char *buf, size_t size)
40 {
41 	if (!buf || !size)
42 		return -1;
43 
44 	err = err > 0 ? err : -err;
45 
46 	if (err < __LIBBPF_ERRNO__START) {
47 		int ret;
48 
49 		ret = strerror_r(err, buf, size);
50 		buf[size - 1] = '\0';
51 		return ret;
52 	}
53 
54 	if (err < __LIBBPF_ERRNO__END) {
55 		const char *msg;
56 
57 		msg = libbpf_strerror_table[ERRNO_OFFSET(err)];
58 		snprintf(buf, size, "%s", msg);
59 		buf[size - 1] = '\0';
60 		return 0;
61 	}
62 
63 	snprintf(buf, size, "Unknown libbpf error %d", err);
64 	buf[size - 1] = '\0';
65 	return -1;
66 }
67