2 * libudev - interface to udev device information
4 * Copyright (C) 2008 Kay Sievers <kay.sievers@vrfy.org>
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
24 #include "libudev-private.h"
26 static ssize_t get_sys_link(struct udev *udev, const char *slink, const char *syspath, char *value, size_t size)
28 char path[UTIL_PATH_SIZE];
32 util_strlcpy(path, syspath, sizeof(path));
33 util_strlcat(path, "/", sizeof(path));
34 util_strlcat(path, slink, sizeof(path));
35 len = readlink(path, path, sizeof(path));
36 if (len < 0 || len >= (ssize_t) sizeof(path))
39 pos = strrchr(path, '/');
43 dbg(udev, "resolved link to: '%s'\n", pos);
44 return util_strlcpy(value, pos, size);
47 ssize_t util_get_sys_subsystem(struct udev *udev, const char *syspath, char *subsystem, size_t size)
49 return get_sys_link(udev, "subsystem", syspath, subsystem, size);
52 ssize_t util_get_sys_driver(struct udev *udev, const char *syspath, char *driver, size_t size)
54 return get_sys_link(udev, "driver", syspath, driver, size);
57 int util_resolve_sys_link(struct udev *udev, char *syspath, size_t size)
59 char link_target[UTIL_PATH_SIZE];
65 len = readlink(syspath, link_target, sizeof(link_target));
68 link_target[len] = '\0';
69 dbg(udev, "path link '%s' points to '%s'\n", syspath, link_target);
71 for (back = 0; strncmp(&link_target[back * 3], "../", 3) == 0; back++)
73 dbg(udev, "base '%s', tail '%s', back %i\n", syspath, &link_target[back * 3], back);
74 for (i = 0; i <= back; i++) {
75 char *pos = strrchr(syspath, '/');
81 dbg(udev, "after moving back '%s'\n", syspath);
82 util_strlcat(syspath, "/", size);
83 util_strlcat(syspath, &link_target[back * 3], size);
87 int util_log_priority(const char *priority)
92 prio = strtol(priority, &endptr, 10);
93 if (endptr[0] == '\0')
95 if (strncasecmp(priority, "err", 3) == 0)
97 if (strcasecmp(priority, "info") == 0)
99 if (strcasecmp(priority, "debug") == 0)
104 size_t util_path_encode(char *s, size_t size)
106 char t[(size * 4)+1];
109 for (i = 0, j = 0; s[i] != '\0' && i < size; i++) {
111 memcpy(&t[j], "\\x2f", 4);
113 } else if (s[i] == '\\') {
114 memcpy(&t[j], "\\x5c", 4);
130 size_t util_path_decode(char *s)
134 for (i = 0, j = 0; s[i] != '\0'; j++) {
135 if (memcmp(&s[i], "\\x2f", 4) == 0) {
138 } else if (memcmp(&s[i], "\\x5c", 4) == 0) {
150 void util_remove_trailing_chars(char *path, char c)
157 while (len > 0 && path[len-1] == c)
161 size_t util_strlcpy(char *dst, const char *src, size_t size)
168 while ((ch = *p++)) {
174 /* If size == 0 there is no space for a final null... */
180 size_t util_strlcat(char *dst, const char *src, size_t size)
187 while (bytes < size && *q) {
192 return (bytes + strlen(src));
194 while ((ch = *p++)) {
204 /* count of characters used to encode one unicode char */
205 static int utf8_encoded_expected_len(const char *str)
207 unsigned char c = (unsigned char)str[0];
211 if ((c & 0xe0) == 0xc0)
213 if ((c & 0xf0) == 0xe0)
215 if ((c & 0xf8) == 0xf0)
217 if ((c & 0xfc) == 0xf8)
219 if ((c & 0xfe) == 0xfc)
224 /* decode one unicode char */
225 static int utf8_encoded_to_unichar(const char *str)
231 len = utf8_encoded_expected_len(str);
236 unichar = str[0] & 0x1f;
239 unichar = (int)str[0] & 0x0f;
242 unichar = (int)str[0] & 0x07;
245 unichar = (int)str[0] & 0x03;
248 unichar = (int)str[0] & 0x01;
254 for (i = 1; i < len; i++) {
255 if (((int)str[i] & 0xc0) != 0x80)
258 unichar |= (int)str[i] & 0x3f;
264 /* expected size used to encode one unicode char */
265 static int utf8_unichar_to_encoded_len(int unichar)
271 if (unichar < 0x10000)
273 if (unichar < 0x200000)
275 if (unichar < 0x4000000)
280 /* check if unicode char has a valid numeric range */
281 static int utf8_unichar_valid_range(int unichar)
283 if (unichar > 0x10ffff)
285 if ((unichar & 0xfffff800) == 0xd800)
287 if ((unichar > 0xfdcf) && (unichar < 0xfdf0))
289 if ((unichar & 0xffff) == 0xffff)
294 /* validate one encoded unicode char and return its length */
295 static int utf8_encoded_valid_unichar(const char *str)
301 len = utf8_encoded_expected_len(str);
309 /* check if expected encoded chars are available */
310 for (i = 0; i < len; i++)
311 if ((str[i] & 0x80) != 0x80)
314 unichar = utf8_encoded_to_unichar(str);
316 /* check if encoded length matches encoded value */
317 if (utf8_unichar_to_encoded_len(unichar) != len)
320 /* check if value has valid range */
321 if (!utf8_unichar_valid_range(unichar))
327 int udev_util_replace_whitespace(const char *str, char *to, size_t len)
331 /* strip trailing whitespace */
332 len = strnlen(str, len);
333 while (len && isspace(str[len-1]))
336 /* strip leading whitespace */
338 while (isspace(str[i]) && (i < len))
343 /* substitute multiple whitespace with a single '_' */
344 if (isspace(str[i])) {
345 while (isspace(str[i]))
355 static int is_whitelisted(char c, const char *white)
357 if ((c >= '0' && c <= '9') ||
358 (c >= 'A' && c <= 'Z') ||
359 (c >= 'a' && c <= 'z') ||
360 strchr("#+-.:=@_", c) != NULL ||
361 (white != NULL && strchr(white, c) != NULL))
366 /* allow chars in whitelist, plain ascii, hex-escaping and valid utf8 */
367 int udev_util_replace_chars(char *str, const char *white)
372 while (str[i] != '\0') {
375 if (is_whitelisted(str[i], white)) {
380 /* accept hex encoding */
381 if (str[i] == '\\' && str[i+1] == 'x') {
386 /* accept valid utf8 */
387 len = utf8_encoded_valid_unichar(&str[i]);
393 /* if space is allowed, replace whitespace with ordinary space */
394 if (isspace(str[i]) && white != NULL && strchr(white, ' ') != NULL) {
401 /* everything else is replaced with '_' */
410 * util_encode_string:
411 * @str: input string to be encoded
412 * @str_enc: output string to store the encoded input string
413 * @len: maximum size of the output string, which may be
414 * four times as long as the input string
416 * Encode all potentially unsafe characters of a string to the
417 * corresponding hex value prefixed by '\x'.
419 * Returns: 0 if the entire string was copied, non-zero otherwise.
421 int udev_util_encode_string(const char *str, char *str_enc, size_t len)
425 if (str == NULL || str_enc == NULL || len == 0)
429 for (i = 0, j = 0; str[i] != '\0'; i++) {
432 seqlen = utf8_encoded_valid_unichar(&str[i]);
434 memcpy(&str_enc[j], &str[i], seqlen);
437 } else if (str[i] == '\\' || !is_whitelisted(str[i], NULL)) {
438 sprintf(&str_enc[j], "\\x%02x", (unsigned char) str[i]);
453 void util_set_fd_cloexec(int fd)
457 flags = fcntl(fd, F_GETFD);
462 fcntl(fd, F_SETFD, flags);
465 unsigned int util_string_hash32(const char *str)
467 unsigned int hash = 0;
469 while (str[0] != '\0') {