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 <regex.h>
  19 #include <unistd.h>
  20 #include <sys/types.h>
  21 #include <sys/stat.h>
  22 #include <fcntl.h>
  23 #include <string.h>
  24 #include <errno.h>
  25
  26 #include "../log.h"
  27
  28 void
  29 __blobmsg_list_init(struct blobmsg_list *list, int offset, int len, blobmsg_list_cmp cmp)
  30 {
  31         avl_init(&list->avl, avl_strcmp, false, NULL);
  32         list->node_offset = offset;
  33         list->node_len = len;
  34         list->cmp = cmp;
  35 }
  36
  37 int
  38 blobmsg_list_fill(struct blobmsg_list *list, void *data, int len, bool array)
  39 {
  40         struct avl_tree *tree = &list->avl;
  41         struct blobmsg_list_node *node;
  42         struct blob_attr *cur;
  43         void *ptr;
  44         int count = 0;
  45         int rem = len;
  46
  47         __blob_for_each_attr(cur, data, rem) {
  48                 if (!blobmsg_check_attr(cur, !array))
  49                         continue;
  50
  51                 ptr = calloc(1, list->node_len);
  52                 if (!ptr)
  53                         return -1;
  54
  55                 node = (void *) ((char *)ptr + list->node_offset);
  56                 if (array)
  57                         node->avl.key = blobmsg_data(cur);
  58                 else
  59                         node->avl.key = blobmsg_name(cur);
  60                 node->data = cur;
  61                 if (avl_insert(tree, &node->avl)) {
  62                         free(ptr);
  63                         continue;
  64                 }
  65
  66                 count++;
  67         }
  68
  69         return count;
  70 }
  71
  72 void
  73 blobmsg_list_move(struct blobmsg_list *list, struct blobmsg_list *src)
  74 {
  75         struct blobmsg_list_node *node, *tmp;
  76         void *ptr;
  77
  78         avl_remove_all_elements(&src->avl, node, avl, tmp) {
  79                 if (avl_insert(&list->avl, &node->avl)) {
  80                         ptr = ((char *) node - list->node_offset);
  81                         free(ptr);
  82                 }
  83         }
  84 }
  85
  86 void
  87 blobmsg_list_free(struct blobmsg_list *list)
  88 {
  89         struct blobmsg_list_node *node, *tmp;
  90         void *ptr;
  91
  92         avl_remove_all_elements(&list->avl, node, avl, tmp) {
  93                 ptr = ((char *) node - list->node_offset);
  94                 free(ptr);
  95         }
  96 }
  97
  98 bool
  99 blobmsg_list_equal(struct blobmsg_list *l1, struct blobmsg_list *l2)
 100 {
 101         struct blobmsg_list_node *n1, *n2;
 102         int count = l1->avl.count;
 103
 104         if (count != l2->avl.count)
 105                 return false;
 106
 107         n1 = avl_first_element(&l1->avl, n1, avl);
 108         n2 = avl_first_element(&l2->avl, n2, avl);
 109
 110         while (count-- > 0) {
 111                 int len;
 112
 113                 len = blob_len(n1->data);
 114                 if (len != blob_len(n2->data))
 115                         return false;
 116
 117                 if (memcmp(n1->data, n2->data, len) != 0)
 118                         return false;
 119
 120                 if (l1->cmp && !l1->cmp(n1, n2))
 121                         return false;
 122
 123                 if (!count)
 124                         break;
 125
 126                 n1 = avl_next_element(n1, avl);
 127                 n2 = avl_next_element(n2, avl);
 128         }
 129
 130         return true;
 131 }
 132
 133 char* get_cmdline_val(const char* name, char* out, int len)
 134 {
 135         char line[CMDLINE_SIZE + 1], *c, *sptr;
 136         int fd = open("/proc/cmdline", O_RDONLY);
 137         ssize_t r = read(fd, line, sizeof(line) - 1);
 138         close(fd);
 139
 140         if (r <= 0)
 141                 return NULL;
 142
 143         line[r] = 0;
 144
 145         for (c = strtok_r(line, " \t\n", &sptr); c;
 146                         c = strtok_r(NULL, " \t\n", &sptr)) {
 147                 char *sep = strchr(c, '=');
 148                 ssize_t klen = sep - c;
 149                 if (klen < 0 || strncmp(name, c, klen) || name[klen] != 0)
 150                         continue;
 151
 152                 strncpy(out, &sep[1], len);
 153                 out[len-1] = 0;
 154                 return out;
 155         }
 156
 157         return NULL;
 158 }
 159
 160 int patch_fd(const char *device, int fd, int flags)
 161 {
 162         int dfd, nfd;
 163
 164         if (device == NULL)
 165                 device = "/dev/null";
 166
 167         if (*device != '/') {
 168                 dfd = open("/dev", O_RDONLY);
 169
 170                 if (dfd < 0)
 171                         return -1;
 172
 173                 nfd = openat(dfd, device, flags);
 174
 175                 close(dfd);
 176         } else {
 177                 nfd = open(device, flags);
 178         }
 179
 180         if (nfd < 0 && strcmp(device, "/dev/null"))
 181                 nfd = open("/dev/null", flags);
 182
 183         if (nfd < 0)
 184                 return -1;
 185
 186         fd = dup2(nfd, fd);
 187
 188         if (nfd > STDERR_FILENO)
 189                 close(nfd);
 190
 191         return (fd < 0) ? -1 : 0;
 192 }
 193
 194 int patch_stdio(const char *device)
 195 {
 196         int fd, rv = 0;
 197         const char *fdname[3] = { "stdin", "stdout", "stderr" };
 198
 199         for (fd = STDIN_FILENO; fd <= STDERR_FILENO; fd++) {
 200                 if (patch_fd(device, fd, fd ? O_WRONLY : O_RDONLY)) {
 201                         ERROR("Failed to redirect %s to %s: %d (%s)\n",
 202                               fdname[fd], device, errno, strerror(errno));
 203                         rv = -1;
 204                 }
 205         }
 206
 207         return rv;
 208 }