utils/utils.c

   1 /*
   2  * Copyright (C) 2013 Felix Fietkau <nbd@openwrt.org>
   3  * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU Lesser General Public License version 2.1
   7  * as published by the Free Software Foundation
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14
  15 #include <libubox/avl.h>
  16 #include <libubox/avl-cmp.h>
  17 #include "utils.h"
  18 #include <asm-generic/setup.h>
  19 #include <regex.h>
  20 #include <unistd.h>
  21 #include <sys/types.h>
  22 #include <sys/stat.h>
  23 #include <fcntl.h>
  24
  25 void
  26 __blobmsg_list_init(struct blobmsg_list *list, int offset, int len, blobmsg_list_cmp cmp)
  27 {
  28         avl_init(&list->avl, avl_strcmp, false, NULL);
  29         list->node_offset = offset;
  30         list->node_len = len;
  31         list->cmp = cmp;
  32 }
  33
  34 int
  35 blobmsg_list_fill(struct blobmsg_list *list, void *data, int len, bool array)
  36 {
  37         struct avl_tree *tree = &list->avl;
  38         struct blobmsg_list_node *node;
  39         struct blob_attr *cur;
  40         void *ptr;
  41         int count = 0;
  42         int rem = len;
  43
  44         __blob_for_each_attr(cur, data, rem) {
  45                 if (!blobmsg_check_attr(cur, !array))
  46                         continue;
  47
  48                 ptr = calloc(1, list->node_len);
  49                 if (!ptr)
  50                         return -1;
  51
  52                 node = (void *) ((char *)ptr + list->node_offset);
  53                 if (array)
  54                         node->avl.key = blobmsg_data(cur);
  55                 else
  56                         node->avl.key = blobmsg_name(cur);
  57                 node->data = cur;
  58                 if (avl_insert(tree, &node->avl)) {
  59                         free(ptr);
  60                         continue;
  61                 }
  62
  63                 count++;
  64         }
  65
  66         return count;
  67 }
  68
  69 void
  70 blobmsg_list_move(struct blobmsg_list *list, struct blobmsg_list *src)
  71 {
  72         struct blobmsg_list_node *node, *tmp;
  73         void *ptr;
  74
  75         avl_remove_all_elements(&src->avl, node, avl, tmp) {
  76                 if (avl_insert(&list->avl, &node->avl)) {
  77                         ptr = ((char *) node - list->node_offset);
  78                         free(ptr);
  79                 }
  80         }
  81 }
  82
  83 void
  84 blobmsg_list_free(struct blobmsg_list *list)
  85 {
  86         struct blobmsg_list_node *node, *tmp;
  87         void *ptr;
  88
  89         avl_remove_all_elements(&list->avl, node, avl, tmp) {
  90                 ptr = ((char *) node - list->node_offset);
  91                 free(ptr);
  92         }
  93 }
  94
  95 bool
  96 blobmsg_list_equal(struct blobmsg_list *l1, struct blobmsg_list *l2)
  97 {
  98         struct blobmsg_list_node *n1, *n2;
  99         int count = l1->avl.count;
 100
 101         if (count != l2->avl.count)
 102                 return false;
 103
 104         n1 = avl_first_element(&l1->avl, n1, avl);
 105         n2 = avl_first_element(&l2->avl, n2, avl);
 106
 107         while (count-- > 0) {
 108                 int len;
 109
 110                 len = blob_len(n1->data);
 111                 if (len != blob_len(n2->data))
 112                         return false;
 113
 114                 if (memcmp(n1->data, n2->data, len) != 0)
 115                         return false;
 116
 117                 if (l1->cmp && !l1->cmp(n1, n2))
 118                         return false;
 119
 120                 if (!count)
 121                         break;
 122
 123                 n1 = avl_next_element(n1, avl);
 124                 n2 = avl_next_element(n2, avl);
 125         }
 126
 127         return true;
 128 }
 129
 130 char* get_cmdline_val(const char* name, char* out, int len)
 131 {
 132         char pattern[CMDLINE_SIZE + 1];
 133         char line[CMDLINE_SIZE + 1];
 134         char *res = NULL, *tty;
 135         int r, fd;
 136         regex_t pat_cmdline;
 137         regmatch_t matches[2];
 138
 139         fd = open("/proc/cmdline", O_RDONLY);
 140         if (fd < 0)
 141                 return NULL;
 142
 143         r = read(fd, line, CMDLINE_SIZE);
 144         if ( r <= 0 ) {
 145                 close(fd);
 146                 return NULL;
 147         }
 148         line[r] = '\0';
 149         close(fd);
 150
 151         sprintf( pattern, "%s=([^ \n]*)", name);
 152         regcomp(&pat_cmdline, pattern, REG_EXTENDED);
 153         if (!regexec(&pat_cmdline, line, 2, matches, 0)) {
 154                 line[matches[1].rm_eo] = '\0';
 155                 tty = (line + matches[1].rm_so);
 156                 strncpy(out, tty, len);
 157                 tty[len-1] = '\0';
 158                 res = out;
 159         }
 160
 161         regfree(&pat_cmdline);
 162
 163         return res;
 164 }