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 #define _GNU_SOURCE
  16 #include <libubox/avl.h>
  17 #include <libubox/avl-cmp.h>
  18 #include "utils.h"
  19 #include <regex.h>
  20 #include <unistd.h>
  21 #include <sys/types.h>
  22 #include <sys/stat.h>
  23 #include <fcntl.h>
  24 #include <string.h>
  25 #include <errno.h>
  26
  27 #include "../log.h"
  28
  29 void
  30 __blobmsg_list_init(struct blobmsg_list *list, int offset, int len, blobmsg_list_cmp cmp)
  31 {
  32         avl_init(&list->avl, avl_strcmp, false, NULL);
  33         list->node_offset = offset;
  34         list->node_len = len;
  35         list->cmp = cmp;
  36 }
  37
  38 int
  39 blobmsg_list_fill(struct blobmsg_list *list, void *data, int len, bool array)
  40 {
  41         struct avl_tree *tree = &list->avl;
  42         struct blobmsg_list_node *node;
  43         struct blob_attr *cur;
  44         void *ptr;
  45         int count = 0;
  46         int rem = len;
  47
  48         __blob_for_each_attr(cur, data, rem) {
  49                 if (!blobmsg_check_attr(cur, !array))
  50                         continue;
  51
  52                 ptr = calloc(1, list->node_len);
  53                 if (!ptr)
  54                         return -1;
  55
  56                 node = (void *) ((char *)ptr + list->node_offset);
  57                 if (array)
  58                         node->avl.key = blobmsg_data(cur);
  59                 else
  60                         node->avl.key = blobmsg_name(cur);
  61                 node->data = cur;
  62                 if (avl_insert(tree, &node->avl)) {
  63                         free(ptr);
  64                         continue;
  65                 }
  66
  67                 count++;
  68         }
  69
  70         return count;
  71 }
  72
  73 void
  74 blobmsg_list_move(struct blobmsg_list *list, struct blobmsg_list *src)
  75 {
  76         struct blobmsg_list_node *node, *tmp;
  77         void *ptr;
  78
  79         avl_remove_all_elements(&src->avl, node, avl, tmp) {
  80                 if (avl_insert(&list->avl, &node->avl)) {
  81                         ptr = ((char *) node - list->node_offset);
  82                         free(ptr);
  83                 }
  84         }
  85 }
  86
  87 void
  88 blobmsg_list_free(struct blobmsg_list *list)
  89 {
  90         struct blobmsg_list_node *node, *tmp;
  91         void *ptr;
  92
  93         avl_remove_all_elements(&list->avl, node, avl, tmp) {
  94                 ptr = ((char *) node - list->node_offset);
  95                 free(ptr);
  96         }
  97 }
  98
  99 bool
 100 blobmsg_list_equal(struct blobmsg_list *l1, struct blobmsg_list *l2)
 101 {
 102         struct blobmsg_list_node *n1, *n2;
 103         int count = l1->avl.count;
 104
 105         if (count != l2->avl.count)
 106                 return false;
 107
 108         n1 = avl_first_element(&l1->avl, n1, avl);
 109         n2 = avl_first_element(&l2->avl, n2, avl);
 110
 111         while (count-- > 0) {
 112                 int len;
 113
 114                 len = blob_len(n1->data);
 115                 if (len != blob_len(n2->data))
 116                         return false;
 117
 118                 if (memcmp(n1->data, n2->data, len) != 0)
 119                         return false;
 120
 121                 if (l1->cmp && !l1->cmp(n1, n2))
 122                         return false;
 123
 124                 if (!count)
 125                         break;
 126
 127                 n1 = avl_next_element(n1, avl);
 128                 n2 = avl_next_element(n2, avl);
 129         }
 130
 131         return true;
 132 }
 133
 134 char* get_cmdline_val(const char* name, char* out, int len)
 135 {
 136         char line[CMDLINE_SIZE + 1], *c, *sptr;
 137         int fd = open("/proc/cmdline", O_RDONLY);
 138         ssize_t r = read(fd, line, sizeof(line) - 1);
 139         close(fd);
 140
 141         if (r <= 0)
 142                 return NULL;
 143
 144         line[r] = 0;
 145
 146         for (c = strtok_r(line, " \t\n", &sptr); c;
 147                         c = strtok_r(NULL, " \t\n", &sptr)) {
 148                 char *sep = strchr(c, '=');
 149                 ssize_t klen = sep - c;
 150                 if (klen < 0 || strncmp(name, c, klen) || name[klen] != 0)
 151                         continue;
 152
 153                 strncpy(out, &sep[1], len);
 154                 out[len-1] = 0;
 155                 return out;
 156         }
 157
 158         return NULL;
 159 }
 160
 161 int patch_fd(const char *device, int fd, int flags)
 162 {
 163         int dfd, nfd;
 164
 165         if (device == NULL)
 166                 device = "/dev/null";
 167
 168         if (*device != '/') {
 169                 dfd = open("/dev", O_PATH|O_DIRECTORY);
 170
 171                 if (dfd < 0)
 172                         return -1;
 173
 174                 nfd = openat(dfd, device, flags);
 175
 176                 close(dfd);
 177         } else {
 178                 nfd = open(device, flags);
 179         }
 180
 181         if (nfd < 0 && strcmp(device, "/dev/null"))
 182                 nfd = open("/dev/null", flags);
 183
 184         if (nfd < 0)
 185                 return -1;
 186
 187         fd = dup2(nfd, fd);
 188
 189         if (nfd > STDERR_FILENO)
 190                 close(nfd);
 191
 192         return (fd < 0) ? -1 : 0;
 193 }
 194
 195 int patch_stdio(const char *device)
 196 {
 197         int fd, rv = 0;
 198         const char *fdname[3] = { "stdin", "stdout", "stderr" };
 199
 200         for (fd = STDIN_FILENO; fd <= STDERR_FILENO; fd++) {
 201                 if (patch_fd(device, fd, fd ? O_WRONLY : O_RDONLY)) {
 202                         ERROR("Failed to redirect %s to %s: %d (%s)\n",
 203                               fdname[fd], device, errno, strerror(errno));
 204                         rv = -1;
 205                 }
 206         }
 207
 208         return rv;
 209 }