xref: /linux/tools/testing/selftests/vfio/lib/libvfio.c (revision 509d3f45847627f4c5cdce004c3ec79262b5239c)
1 // SPDX-License-Identifier: GPL-2.0-only
2 
3 #include <stdio.h>
4 #include <stdlib.h>
5 
6 #include "../../../kselftest.h"
7 #include <libvfio.h>
8 
9 static bool is_bdf(const char *str)
10 {
11 	unsigned int s, b, d, f;
12 	int length, count;
13 
14 	count = sscanf(str, "%4x:%2x:%2x.%2x%n", &s, &b, &d, &f, &length);
15 	return count == 4 && length == strlen(str);
16 }
17 
18 static char **get_bdfs_cmdline(int *argc, char *argv[], int *nr_bdfs)
19 {
20 	int i;
21 
22 	for (i = *argc - 1; i > 0 && is_bdf(argv[i]); i--)
23 		continue;
24 
25 	i++;
26 	*nr_bdfs = *argc - i;
27 	*argc -= *nr_bdfs;
28 
29 	return *nr_bdfs ? &argv[i] : NULL;
30 }
31 
32 static char *get_bdf_env(void)
33 {
34 	char *bdf;
35 
36 	bdf = getenv("VFIO_SELFTESTS_BDF");
37 	if (!bdf)
38 		return NULL;
39 
40 	VFIO_ASSERT_TRUE(is_bdf(bdf), "Invalid BDF: %s\n", bdf);
41 	return bdf;
42 }
43 
44 char **vfio_selftests_get_bdfs(int *argc, char *argv[], int *nr_bdfs)
45 {
46 	static char *env_bdf;
47 	char **bdfs;
48 
49 	bdfs = get_bdfs_cmdline(argc, argv, nr_bdfs);
50 	if (bdfs)
51 		return bdfs;
52 
53 	env_bdf = get_bdf_env();
54 	if (env_bdf) {
55 		*nr_bdfs = 1;
56 		return &env_bdf;
57 	}
58 
59 	fprintf(stderr, "Unable to determine which device(s) to use, skipping test.\n");
60 	fprintf(stderr, "\n");
61 	fprintf(stderr, "To pass the device address via environment variable:\n");
62 	fprintf(stderr, "\n");
63 	fprintf(stderr, "    export VFIO_SELFTESTS_BDF=\"segment:bus:device.function\"\n");
64 	fprintf(stderr, "    %s [options]\n", argv[0]);
65 	fprintf(stderr, "\n");
66 	fprintf(stderr, "To pass the device address(es) via argv:\n");
67 	fprintf(stderr, "\n");
68 	fprintf(stderr, "    %s [options] segment:bus:device.function ...\n", argv[0]);
69 	fprintf(stderr, "\n");
70 	exit(KSFT_SKIP);
71 }
72 
73 const char *vfio_selftests_get_bdf(int *argc, char *argv[])
74 {
75 	int nr_bdfs;
76 
77 	return vfio_selftests_get_bdfs(argc, argv, &nr_bdfs)[0];
78 }
79