udev_utils.c

   1 /*
   2  * udev_lib - generic stuff used by udev
   3  *
   4  * Copyright (C) 2004 Kay Sievers <kay@vrfy.org>
   5  *
   6  *      This program is free software; you can redistribute it and/or modify it
   7  *      under the terms of the GNU General Public License as published by the
   8  *      Free Software Foundation version 2 of the License.
   9  *
  10  *      This program is distributed in the hope that it will be useful, but
  11  *      WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  *      General Public License for more details.
  14  *
  15  *      You should have received a copy of the GNU General Public License along
  16  *      with this program; if not, write to the Free Software Foundation, Inc.,
  17  *      675 Mass Ave, Cambridge, MA 02139, USA.
  18  *
  19  */
  20
  21
  22 #include <stdlib.h>
  23 #include <stdio.h>
  24 #include <stddef.h>
  25 #include <unistd.h>
  26 #include <fcntl.h>
  27 #include <errno.h>
  28 #include <ctype.h>
  29 #include <dirent.h>
  30 #include <sys/stat.h>
  31 #include <sys/mman.h>
  32 #include <sys/utsname.h>
  33
  34 #include "udev.h"
  35 #include "logging.h"
  36 #include "udev_utils.h"
  37 #include "list.h"
  38
  39
  40 void udev_init_device(struct udevice *udev, const char* devpath, const char *subsystem)
  41 {
  42         memset(udev, 0x00, sizeof(struct udevice));
  43
  44         if (devpath)
  45                 strfieldcpy(udev->devpath, devpath);
  46         if (subsystem)
  47                 strfieldcpy(udev->subsystem, subsystem);
  48
  49         if (strcmp(udev->subsystem, "block") == 0)
  50                 udev->type = 'b';
  51         else if (strcmp(udev->subsystem, "net") == 0)
  52                 udev->type = 'n';
  53         else if (strncmp(udev->devpath, "/block/", 7) == 0)
  54                 udev->type = 'b';
  55         else if (strncmp(udev->devpath, "/class/net/", 11) == 0)
  56                 udev->type = 'n';
  57         else if (strncmp(udev->devpath, "/class/", 7) == 0)
  58                 udev->type = 'c';
  59
  60         udev->mode = 0660;
  61         strcpy(udev->owner, "root");
  62         strcpy(udev->group, "root");
  63 }
  64
  65 int kernel_release_satisfactory(unsigned int version, unsigned int patchlevel, unsigned int sublevel)
  66 {
  67         static unsigned int kversion = 0;
  68         static unsigned int kpatchlevel;
  69         static unsigned int ksublevel;
  70
  71         if (kversion == 0) {
  72                 struct utsname uts;
  73                 if (uname(&uts) != 0)
  74                         return -1;
  75
  76                 if (sscanf (uts.release, "%u.%u.%u", &kversion, &kpatchlevel, &ksublevel) != 3) {
  77                         kversion = 0;
  78                         return -1;
  79                 }
  80         }
  81
  82         if (kversion >= version && kpatchlevel >= patchlevel && ksublevel >= sublevel)
  83                 return 1;
  84         else
  85                 return 0;
  86 }
  87
  88 int create_path(const char *path)
  89 {
  90         char p[NAME_SIZE];
  91         char *pos;
  92         struct stat stats;
  93
  94         strcpy (p, path);
  95         pos = strrchr(p, '/');
  96         if (pos == p || pos == NULL)
  97                 return 0;
  98
  99         while (pos[-1] == '/')
 100                 pos--;
 101
 102         pos[0] = '\0';
 103
 104         dbg("stat '%s'\n", p);
 105         if (stat (p, &stats) == 0 && (stats.st_mode & S_IFMT) == S_IFDIR)
 106                 return 0;
 107
 108         if (create_path (p) != 0)
 109                 return -1;
 110
 111         dbg("mkdir '%s'\n", p);
 112         return mkdir(p, 0755);
 113 }
 114
 115 /* Reset permissions on the device node, before unlinking it to make sure,
 116  * that permisions of possible hard links will be removed too.
 117  */
 118 int unlink_secure(const char *filename)
 119 {
 120         int retval;
 121
 122         retval = chown(filename, 0, 0);
 123         if (retval)
 124                 dbg("chown(%s, 0, 0) failed with error '%s'", filename, strerror(errno));
 125
 126         retval = chmod(filename, 0000);
 127         if (retval)
 128                 dbg("chmod(%s, 0000) failed with error '%s'", filename, strerror(errno));
 129
 130         retval = unlink(filename);
 131         if (errno == ENOENT)
 132                 retval = 0;
 133
 134         if (retval)
 135                 dbg("unlink(%s) failed with error '%s'", filename, strerror(errno));
 136
 137         return retval;
 138 }
 139
 140 int parse_get_pair(char **orig_string, char **left, char **right)
 141 {
 142         char *temp;
 143         char *string = *orig_string;
 144
 145         if (!string)
 146                 return -ENODEV;
 147
 148         /* eat any whitespace */
 149         while (isspace(*string) || *string == ',')
 150                 ++string;
 151
 152         /* split based on '=' */
 153         temp = strsep(&string, "=");
 154         *left = temp;
 155         if (!string)
 156                 return -ENODEV;
 157
 158         /* take the right side and strip off the '"' */
 159         while (isspace(*string))
 160                 ++string;
 161         if (*string == '"')
 162                 ++string;
 163         else
 164                 return -ENODEV;
 165
 166         temp = strsep(&string, "\"");
 167         if (!string || *temp == '\0')
 168                 return -ENODEV;
 169         *right = temp;
 170         *orig_string = string;
 171
 172         return 0;
 173 }
 174
 175 int file_map(const char *filename, char **buf, size_t *bufsize)
 176 {
 177         struct stat stats;
 178         int fd;
 179
 180         fd = open(filename, O_RDONLY);
 181         if (fd < 0) {
 182                 return -1;
 183         }
 184
 185         if (fstat(fd, &stats) < 0) {
 186                 close(fd);
 187                 return -1;
 188         }
 189
 190         *buf = mmap(NULL, stats.st_size, PROT_READ, MAP_SHARED, fd, 0);
 191         if (*buf == MAP_FAILED) {
 192                 close(fd);
 193                 return -1;
 194         }
 195         *bufsize = stats.st_size;
 196
 197         close(fd);
 198
 199         return 0;
 200 }
 201
 202 void file_unmap(char *buf, size_t bufsize)
 203 {
 204         munmap(buf, bufsize);
 205 }
 206
 207 /* return number of chars until the next newline, skip escaped newline */
 208 size_t buf_get_line(const char *buf, size_t buflen, size_t cur)
 209 {
 210         int escape = 0;
 211         size_t count;
 212
 213         for (count = cur; count < buflen; count++) {
 214                 if (!escape && buf[count] == '\n')
 215                         break;
 216
 217                 if (buf[count] == '\\')
 218                         escape = 1;
 219                 else
 220                         escape = 0;
 221         }
 222
 223         return count - cur;
 224 }
 225
 226 void no_trailing_slash(char *path)
 227 {
 228         size_t len;
 229
 230         len = strlen(path);
 231         while (len > 0 && path[len-1] == '/')
 232                 path[--len] = '\0';
 233 }
 234
 235 struct files {
 236         struct list_head list;
 237         char name[NAME_SIZE];
 238 };
 239
 240 /* sort files in lexical order */
 241 static int file_list_insert(char *filename, struct list_head *file_list)
 242 {
 243         struct files *loop_file;
 244         struct files *new_file;
 245
 246         list_for_each_entry(loop_file, file_list, list) {
 247                 if (strcmp(loop_file->name, filename) > 0) {
 248                         break;
 249                 }
 250         }
 251
 252         new_file = malloc(sizeof(struct files));
 253         if (new_file == NULL) {
 254                 dbg("error malloc");
 255                 return -ENOMEM;
 256         }
 257
 258         strfieldcpy(new_file->name, filename);
 259         list_add_tail(&new_file->list, &loop_file->list);
 260         return 0;
 261 }
 262
 263 /* calls function for every file found in specified directory */
 264 int call_foreach_file(file_fnct_t fnct, const char *dirname,
 265                       const char *suffix, void *data)
 266 {
 267         struct dirent *ent;
 268         DIR *dir;
 269         char *ext;
 270         struct files *loop_file;
 271         struct files *tmp_file;
 272         LIST_HEAD(file_list);
 273
 274         dbg("open directory '%s'", dirname);
 275         dir = opendir(dirname);
 276         if (dir == NULL) {
 277                 dbg("unable to open '%s'", dirname);
 278                 return -1;
 279         }
 280
 281         while (1) {
 282                 ent = readdir(dir);
 283                 if (ent == NULL || ent->d_name[0] == '\0')
 284                         break;
 285
 286                 if ((ent->d_name[0] == '.') || (ent->d_name[0] == COMMENT_CHARACTER))
 287                         continue;
 288
 289                 /* look for file with specified suffix */
 290                 ext = strrchr(ent->d_name, '.');
 291                 if (ext == NULL)
 292                         continue;
 293
 294                 if (strcmp(ext, suffix) != 0)
 295                         continue;
 296
 297                 dbg("put file '%s/%s' in list", dirname, ent->d_name);
 298                 file_list_insert(ent->d_name, &file_list);
 299         }
 300
 301         /* call function for every file in the list */
 302         list_for_each_entry_safe(loop_file, tmp_file, &file_list, list) {
 303                 char filename[NAME_SIZE];
 304
 305                 snprintf(filename, NAME_SIZE, "%s/%s", dirname, loop_file->name);
 306                 filename[NAME_SIZE-1] = '\0';
 307
 308                 fnct(filename, data);
 309
 310                 list_del(&loop_file->list);
 311                 free(loop_file);
 312         }
 313
 314         closedir(dir);
 315         return 0;
 316 }