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 	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