xref: /linux/tools/lib/bpf/libbpf_errno.c (revision e9f0878c4b2004ac19581274c1ae4c61ae3ca70e)
1 // SPDX-License-Identifier: LGPL-2.1
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  * This program is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public
11  * License as published by the Free Software Foundation;
12  * version 2.1 of the License (not later!)
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU Lesser General Public License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public
20  * License along with this program; if not,  see <http://www.gnu.org/licenses>
21  */
22 
23 #include <stdio.h>
24 #include <string.h>
25 
26 #include "libbpf.h"
27 
28 #define ERRNO_OFFSET(e)		((e) - __LIBBPF_ERRNO__START)
29 #define ERRCODE_OFFSET(c)	ERRNO_OFFSET(LIBBPF_ERRNO__##c)
30 #define NR_ERRNO	(__LIBBPF_ERRNO__END - __LIBBPF_ERRNO__START)
31 
32 static const char *libbpf_strerror_table[NR_ERRNO] = {
33 	[ERRCODE_OFFSET(LIBELF)]	= "Something wrong in libelf",
34 	[ERRCODE_OFFSET(FORMAT)]	= "BPF object format invalid",
35 	[ERRCODE_OFFSET(KVERSION)]	= "'version' section incorrect or lost",
36 	[ERRCODE_OFFSET(ENDIAN)]	= "Endian mismatch",
37 	[ERRCODE_OFFSET(INTERNAL)]	= "Internal error in libbpf",
38 	[ERRCODE_OFFSET(RELOC)]		= "Relocation failed",
39 	[ERRCODE_OFFSET(VERIFY)]	= "Kernel verifier blocks program loading",
40 	[ERRCODE_OFFSET(PROG2BIG)]	= "Program too big",
41 	[ERRCODE_OFFSET(KVER)]		= "Incorrect kernel version",
42 	[ERRCODE_OFFSET(PROGTYPE)]	= "Kernel doesn't support this program type",
43 	[ERRCODE_OFFSET(WRNGPID)]	= "Wrong pid in netlink message",
44 	[ERRCODE_OFFSET(INVSEQ)]	= "Invalid netlink sequence",
45 };
46 
47 int libbpf_strerror(int err, char *buf, size_t size)
48 {
49 	if (!buf || !size)
50 		return -1;
51 
52 	err = err > 0 ? err : -err;
53 
54 	if (err < __LIBBPF_ERRNO__START) {
55 		int ret;
56 
57 		ret = strerror_r(err, buf, size);
58 		buf[size - 1] = '\0';
59 		return ret;
60 	}
61 
62 	if (err < __LIBBPF_ERRNO__END) {
63 		const char *msg;
64 
65 		msg = libbpf_strerror_table[ERRNO_OFFSET(err)];
66 		snprintf(buf, size, "%s", msg);
67 		buf[size - 1] = '\0';
68 		return 0;
69 	}
70 
71 	snprintf(buf, size, "Unknown libbpf error %d", err);
72 	buf[size - 1] = '\0';
73 	return -1;
74 }
75