xref: /freebsd/contrib/ofed/libibumad/sysfs.c (revision ccb59683b98360afaf5b5bb641a68fea22c68d0b)
1 /*
2  * Copyright (c) 2004-2008 Voltaire Inc.  All rights reserved.
3  *
4  * This software is available to you under a choice of one of two
5  * licenses.  You may choose to be licensed under the terms of the GNU
6  * General Public License (GPL) Version 2, available from the file
7  * COPYING in the main directory of this source tree, or the
8  * OpenIB.org BSD license below:
9  *
10  *     Redistribution and use in source and binary forms, with or
11  *     without modification, are permitted provided that the following
12  *     conditions are met:
13  *
14  *      - Redistributions of source code must retain the above
15  *        copyright notice, this list of conditions and the following
16  *        disclaimer.
17  *
18  *      - Redistributions in binary form must reproduce the above
19  *        copyright notice, this list of conditions and the following
20  *        disclaimer in the documentation and/or other materials
21  *        provided with the distribution.
22  *
23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30  * SOFTWARE.
31  *
32  */
33 #include <config.h>
34 
35 #include <infiniband/endian.h>
36 #include <inttypes.h>
37 #include <string.h>
38 #include <errno.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <unistd.h>
42 #include <sys/types.h>
43 #include <sys/stat.h>
44 #include <sys/sysctl.h>
45 #include <fcntl.h>
46 #include <dirent.h>
47 #include "sysfs.h"
48 
49 static int ret_code(void)
50 {
51 	int e = errno;
52 
53 	if (e > 0)
54 		return -e;
55 	return e;
56 }
57 
58 int sys_read_string(const char *dir_name, const char *file_name, char *str, int max_len)
59 {
60 	char path[256], *s;
61 	size_t len;
62 
63 	snprintf(path, sizeof(path), "%s/%s", dir_name, file_name);
64 
65 	len = max_len;
66 	if (sysctlbyname(PATH_TO_SYS(path), str, &len, NULL, 0) == -1)
67 		return ret_code();
68 
69 	str[(len < max_len) ? len : max_len - 1] = 0;
70 
71 	if ((s = strrchr(str, '\n')))
72 		*s = 0;
73 
74 	return 0;
75 }
76 
77 int sys_read_guid(const char *dir_name, const char *file_name, __be64 *net_guid)
78 {
79 	char buf[32], *str, *s;
80 	uint64_t guid;
81 	int r, i;
82 
83 	if ((r = sys_read_string(dir_name, file_name, buf, sizeof(buf))) < 0)
84 		return r;
85 
86 	guid = 0;
87 
88 	for (s = buf, i = 0; i < 4; i++) {
89 		if (!(str = strsep(&s, ": \t\n")))
90 			return -EINVAL;
91 		guid = (guid << 16) | (strtoul(str, NULL, 16) & 0xffff);
92 	}
93 
94 	*net_guid = htobe64(guid);
95 
96 	return 0;
97 }
98 
99 int sys_read_gid(const char *dir_name, const char *file_name,
100 		 union umad_gid *gid)
101 {
102 	char buf[64], *str, *s;
103 	__be16 *ugid = (__be16 *) gid;
104 	int r, i;
105 
106 	if ((r = sys_read_string(dir_name, file_name, buf, sizeof(buf))) < 0)
107 		return r;
108 
109 	for (s = buf, i = 0; i < 8; i++) {
110 		if (!(str = strsep(&s, ": \t\n")))
111 			return -EINVAL;
112 		ugid[i] = htobe16(strtoul(str, NULL, 16) & 0xffff);
113 	}
114 
115 	return 0;
116 }
117 
118 int sys_read_uint64(const char *dir_name, const char *file_name, uint64_t * u)
119 {
120 	char buf[32];
121 	int r;
122 
123 	if ((r = sys_read_string(dir_name, file_name, buf, sizeof(buf))) < 0)
124 		return r;
125 
126 	*u = strtoull(buf, NULL, 0);
127 
128 	return 0;
129 }
130 
131 int sys_read_uint(const char *dir_name, const char *file_name, unsigned *u)
132 {
133 	char buf[32];
134 	int r;
135 
136 	if ((r = sys_read_string(dir_name, file_name, buf, sizeof(buf))) < 0)
137 		return r;
138 
139 	*u = strtoul(buf, NULL, 0);
140 
141 	return 0;
142 }
143 
144 #define	DIRECTSIZ(namlen)						\
145 	(((uintptr_t)&((struct dirent *)0)->d_name +			\
146 	((namlen)+1)*sizeof(((struct dirent *)0)->d_name[0]) + 3) & ~3)
147 
148 int
149 sys_scandir(const char *dirname, struct dirent ***namelist,
150     int (*select)(const struct dirent *),
151     int (*compar)(const struct dirent **, const struct dirent **))
152 {
153 	struct dirent **names;
154 	struct dirent **names2;
155 	struct dirent *dp;
156 	char name[1024];
157 	int lsname[22];
158 	int chname[22];
159 	int name2[22];
160 	int oid[22];
161 	char *s;
162 	size_t n1, n2;
163 	size_t len, oidlen, namlen;
164 	int cnt, max;
165 	int err;
166 	int i;
167 
168 	*namelist = NULL;
169 	if (strlcpy(name, PATH_TO_SYS(dirname), sizeof(name)) >= sizeof(name))
170 		return (-EINVAL);
171 	/*
172 	 * Resolve the path.
173 	 */
174 	len = sizeof(oid) / sizeof(int);
175 	namlen = strlen(name) + 1;
176 	if (sysctlnametomib(name, oid, &len) != 0)
177 		return (-errno);
178 	lsname[0] = 0;	/* Root */
179 	lsname[1] = 2;	/* Get next */
180 	memcpy(lsname+2, oid, len * sizeof(int));
181 	n1 = 2 + len;
182 	oidlen = len;
183 	/*
184 	 * Setup the return list of dirents.
185 	 */
186 	cnt = 0;
187 	max = 64;
188 	names = malloc(max * sizeof(void *));
189 	if (names == NULL)
190 		return (-ENOMEM);
191 
192 	for (;;) {
193 		n2 = sizeof(name2);
194 		if (sysctl(lsname, n1, name2, &n2, 0, 0) < 0) {
195 			if (errno == ENOENT)
196 				break;
197 			goto errout;
198 		}
199 		n2 /= sizeof(int);
200 		if (n2 < oidlen)
201 			break;
202 		for (i = 0; i < oidlen; i++)
203 			if (name2[i] != oid[i])
204 				goto out;
205 		chname[0] = 0;	/* root */
206 		chname[1] = 1;	/* oid name */
207 		memcpy(chname + 2, name2, n2 * sizeof(int));
208 		memcpy(lsname + 2, name2, n2 * sizeof(int));
209 		n1 = 2 + n2;
210 		/*
211 		 * scandir() is not supposed to go deeper than the requested
212 		 * directory but sysctl also doesn't return a node for
213 		 * 'subdirectories' so we have to find a file in the subdir
214 		 * and then truncate the name to report it.
215 	 	 */
216 		if (n2 > oidlen + 1) {
217 			/* Skip to the next name after this one. */
218 			n1 = 2 + oidlen + 1;
219 			lsname[n1 - 1]++;
220 		}
221 		len = sizeof(name);
222 		if (sysctl(chname, n2 + 2, name, &len, 0, 0) < 0)
223 			goto errout;
224 		if (len <= 0 || len < namlen)
225 			goto out;
226 		s = name + namlen;
227 		/* Just keep the first level name. */
228 		if (strchr(s, '.'))
229 			*strchr(s, '.') = '\0';
230 		len = strlen(s) + 1;
231 		dp = malloc(DIRECTSIZ(len));
232 		dp->d_reclen = DIRECTSIZ(len);
233 		dp->d_namlen = len;
234 		memcpy(&dp->d_name, s, len);
235 		if (select && !select(dp)) {
236 			free(dp);
237 			continue;
238 		}
239 		if (cnt == max) {
240 			max *= 2;
241 			names2 = realloc(names, max * sizeof(void *));
242 			if (names2 == NULL) {
243 				errno = ENOMEM;
244 				free(dp);
245 				goto errout;
246 			}
247 			names = names2;
248 		}
249 		names[cnt++] = dp;
250 	}
251 out:
252 	if (cnt && compar)
253 		qsort(names, cnt, sizeof(struct dirent *),
254 		    (int (*)(const void *, const void *))compar);
255 
256 	*namelist = names;
257 
258 	return (cnt);
259 
260 errout:
261 	err = errno;
262 	for (i = 0; i < cnt; i++)
263 		free(names[i]);
264 	free(names);
265 	return (-err);
266 }
267