src/basic/device-nodes.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 /***
   3   Copyright © 2008-2011 Kay Sievers
   4 ***/
   5
   6 #include <errno.h>
   7 #include <stdio.h>
   8 #include <string.h>
   9
  10 #include "device-nodes.h"
  11 #include "utf8.h"
  12
  13 int whitelisted_char_for_devnode(char c, const char *white) {
  14
  15         if ((c >= '0' && c <= '9') ||
  16             (c >= 'A' && c <= 'Z') ||
  17             (c >= 'a' && c <= 'z') ||
  18             strchr("#+-.:=@_", c) != NULL ||
  19             (white != NULL && strchr(white, c) != NULL))
  20                 return 1;
  21
  22         return 0;
  23 }
  24
  25 int encode_devnode_name(const char *str, char *str_enc, size_t len) {
  26         size_t i, j;
  27
  28         if (!str || !str_enc)
  29                 return -EINVAL;
  30
  31         for (i = 0, j = 0; str[i] != '\0'; i++) {
  32                 int seqlen;
  33
  34                 seqlen = utf8_encoded_valid_unichar(&str[i]);
  35                 if (seqlen > 1) {
  36
  37                         if (len-j < (size_t)seqlen)
  38                                 return -EINVAL;
  39
  40                         memcpy(&str_enc[j], &str[i], seqlen);
  41                         j += seqlen;
  42                         i += (seqlen-1);
  43
  44                 } else if (str[i] == '\\' || !whitelisted_char_for_devnode(str[i], NULL)) {
  45
  46                         if (len-j < 4)
  47                                 return -EINVAL;
  48
  49                         sprintf(&str_enc[j], "\\x%02x", (unsigned char) str[i]);
  50                         j += 4;
  51
  52                 } else {
  53                         if (len-j < 1)
  54                                 return -EINVAL;
  55
  56                         str_enc[j] = str[i];
  57                         j++;
  58                 }
  59         }
  60
  61         if (len-j < 1)
  62                 return -EINVAL;
  63
  64         str_enc[j] = '\0';
  65         return 0;
  66 }