miscutils/makedevs.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * public domain -- Dave 'Kill a Cop' Cinege <dcinege@psychosis.com>
   4  *
   5  * makedevs
   6  * Make ranges of device files quickly.
   7  * known bugs: can't deal with alpha ranges
   8  */
   9 //config:config MAKEDEVS
  10 //config:       bool "makedevs"
  11 //config:       default y
  12 //config:       help
  13 //config:         'makedevs' is a utility used to create a batch of devices with
  14 //config:         one command.
  15 //config:
  16 //config:         There are two choices for command line behaviour, the interface
  17 //config:         as used by LEAF/Linux Router Project, or a device table file.
  18 //config:
  19 //config:         'leaf' is traditionally what busybox follows, it allows multiple
  20 //config:         devices of a particluar type to be created per command.
  21 //config:         e.g. /dev/hda[0-9]
  22 //config:         Device properties are passed as command line arguments.
  23 //config:
  24 //config:         'table' reads device properties from a file or stdin, allowing
  25 //config:         a batch of unrelated devices to be made with one command.
  26 //config:         User/group names are allowed as an alternative to uid/gid.
  27 //config:
  28 //config:choice
  29 //config:       prompt "Choose makedevs behaviour"
  30 //config:       depends on MAKEDEVS
  31 //config:       default FEATURE_MAKEDEVS_TABLE
  32 //config:
  33 //config:config FEATURE_MAKEDEVS_LEAF
  34 //config:       bool "leaf"
  35 //config:
  36 //config:config FEATURE_MAKEDEVS_TABLE
  37 //config:       bool "table"
  38 //config:
  39 //config:endchoice
  40
  41 //applet:IF_MAKEDEVS(APPLET(makedevs, BB_DIR_SBIN, BB_SUID_DROP))
  42
  43 //kbuild:lib-$(CONFIG_MAKEDEVS) += makedevs.o
  44
  45 //usage:#if ENABLE_FEATURE_MAKEDEVS_LEAF
  46 //usage:#define makedevs_trivial_usage
  47 //usage:       "NAME TYPE MAJOR MINOR FIRST LAST [s]"
  48 //usage:#define makedevs_full_usage "\n\n"
  49 //usage:       "Create a range of block or character special files"
  50 //usage:     "\n"
  51 //usage:     "\nTYPE is:"
  52 //usage:     "\n        b       Block device"
  53 //usage:     "\n        c       Character device"
  54 //usage:     "\n        f       FIFO, MAJOR and MINOR are ignored"
  55 //usage:     "\n"
  56 //usage:     "\nFIRST..LAST specify numbers appended to NAME."
  57 //usage:     "\nIf 's' is the last argument, the base device is created as well."
  58 //usage:     "\n"
  59 //usage:     "\nExamples:"
  60 //usage:     "\n        makedevs /dev/ttyS c 4 66 2 63   ->  ttyS2-ttyS63"
  61 //usage:     "\n        makedevs /dev/hda b 3 0 0 8 s    ->  hda,hda1-hda8"
  62 //usage:
  63 //usage:#define makedevs_example_usage
  64 //usage:       "# makedevs /dev/ttyS c 4 66 2 63\n"
  65 //usage:       "[creates ttyS2-ttyS63]\n"
  66 //usage:       "# makedevs /dev/hda b 3 0 0 8 s\n"
  67 //usage:       "[creates hda,hda1-hda8]\n"
  68 //usage:#endif
  69 //usage:
  70 //usage:#if ENABLE_FEATURE_MAKEDEVS_TABLE
  71 //usage:#define makedevs_trivial_usage
  72 //usage:       "[-d device_table] rootdir"
  73 //usage:#define makedevs_full_usage "\n\n"
  74 //usage:       "Create a range of special files as specified in a device table.\n"
  75 //usage:       "Device table entries take the form of:\n"
  76 //usage:       "<name> <type> <mode> <uid> <gid> <major> <minor> <start> <inc> <count>\n"
  77 //usage:       "Where name is the file name, type can be one of:\n"
  78 //usage:       "        f       Regular file\n"
  79 //usage:       "        d       Directory\n"
  80 //usage:       "        c       Character device\n"
  81 //usage:       "        b       Block device\n"
  82 //usage:       "        p       Fifo (named pipe)\n"
  83 //usage:       "uid is the user id for the target file, gid is the group id for the\n"
  84 //usage:       "target file. The rest of the entries (major, minor, etc) apply to\n"
  85 //usage:       "to device special files. A '-' may be used for blank entries."
  86 //usage:
  87 //usage:#define makedevs_example_usage
  88 //usage:       "For example:\n"
  89 //usage:       "<name>    <type> <mode><uid><gid><major><minor><start><inc><count>\n"
  90 //usage:       "/dev         d   755    0    0    -      -      -      -    -\n"
  91 //usage:       "/dev/console c   666    0    0    5      1      -      -    -\n"
  92 //usage:       "/dev/null    c   666    0    0    1      3      0      0    -\n"
  93 //usage:       "/dev/zero    c   666    0    0    1      5      0      0    -\n"
  94 //usage:       "/dev/hda     b   640    0    0    3      0      0      0    -\n"
  95 //usage:       "/dev/hda     b   640    0    0    3      1      1      1    15\n\n"
  96 //usage:       "Will Produce:\n"
  97 //usage:       "/dev\n"
  98 //usage:       "/dev/console\n"
  99 //usage:       "/dev/null\n"
 100 //usage:       "/dev/zero\n"
 101 //usage:       "/dev/hda\n"
 102 //usage:       "/dev/hda[0-15]\n"
 103 //usage:#endif
 104
 105 #include "libbb.h"
 106
 107 #if ENABLE_FEATURE_MAKEDEVS_LEAF
 108 /*
 109 makedevs NAME TYPE MAJOR MINOR FIRST LAST [s]
 110 TYPEs:
 111 b       Block device
 112 c       Character device
 113 f       FIFO
 114
 115 FIRST..LAST specify numbers appended to NAME.
 116 If 's' is the last argument, the base device is created as well.
 117 Examples:
 118         makedevs /dev/ttyS c 4 66 2 63   ->  ttyS2-ttyS63
 119         makedevs /dev/hda b 3 0 0 8 s    ->  hda,hda1-hda8
 120 */
 121 int makedevs_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 122 int makedevs_main(int argc, char **argv)
 123 {
 124         mode_t mode;
 125         char *basedev, *type, *nodname, *buf;
 126         int Smajor, Sminor, S, E;
 127
 128         if (argc < 7 || argv[1][0] == '-')
 129                 bb_show_usage();
 130
 131         basedev = argv[1];
 132         buf = xasprintf("%s%u", argv[1], (unsigned)-1);
 133         type = argv[2];
 134         Smajor = xatoi_positive(argv[3]);
 135         Sminor = xatoi_positive(argv[4]);
 136         S = xatoi_positive(argv[5]);
 137         E = xatoi_positive(argv[6]);
 138         nodname = argv[7] ? basedev : buf;
 139
 140         mode = 0660;
 141         switch (type[0]) {
 142         case 'c':
 143                 mode |= S_IFCHR;
 144                 break;
 145         case 'b':
 146                 mode |= S_IFBLK;
 147                 break;
 148         case 'f':
 149                 mode |= S_IFIFO;
 150                 break;
 151         default:
 152                 bb_show_usage();
 153         }
 154
 155         while (S <= E) {
 156                 sprintf(buf, "%s%u", basedev, S);
 157
 158                 /* if mode != S_IFCHR and != S_IFBLK,
 159                  * third param in mknod() ignored */
 160                 if (mknod(nodname, mode, makedev(Smajor, Sminor)) != 0
 161                  && errno != EEXIST
 162                 ) {
 163                         bb_perror_msg("can't create '%s'", nodname);
 164                 }
 165
 166                 /*if (nodname == basedev)*/ /* ex. /dev/hda - to /dev/hda1 ... */
 167                         nodname = buf;
 168                 S++;
 169                 Sminor++;
 170         }
 171
 172         return 0;
 173 }
 174
 175 #elif ENABLE_FEATURE_MAKEDEVS_TABLE
 176
 177 /* Licensed under GPLv2 or later, see file LICENSE in this source tree. */
 178
 179 int makedevs_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 180 int makedevs_main(int argc UNUSED_PARAM, char **argv)
 181 {
 182         parser_t *parser;
 183         char *line = (char *)"-";
 184         int ret = EXIT_SUCCESS;
 185
 186         opt_complementary = "=1"; /* exactly one param */
 187         getopt32(argv, "d:", &line);
 188         argv += optind;
 189
 190         xchdir(*argv); /* ensure root dir exists */
 191
 192         umask(0);
 193
 194         printf("rootdir=%s\ntable=", *argv);
 195         if (NOT_LONE_DASH(line)) {
 196                 printf("'%s'\n", line);
 197         } else {
 198                 puts("<stdin>");
 199         }
 200
 201         parser = config_open(line);
 202         while (config_read(parser, &line, 1, 1, "# \t", PARSE_NORMAL)) {
 203                 int linenum;
 204                 char type;
 205                 unsigned mode = 0755;
 206                 unsigned major = 0;
 207                 unsigned minor = 0;
 208                 unsigned count = 0;
 209                 unsigned increment = 0;
 210                 unsigned start = 0;
 211                 char name[41];
 212                 char user[41];
 213                 char group[41];
 214                 char *full_name = name;
 215                 uid_t uid;
 216                 gid_t gid;
 217
 218                 linenum = parser->lineno;
 219
 220                 if ((2 > sscanf(line, "%40s %c %o %40s %40s %u %u %u %u %u",
 221                                         name, &type, &mode, user, group,
 222                                         &major, &minor, &start, &increment, &count))
 223                  || ((unsigned)(major | minor | start | count | increment) > 255)
 224                 ) {
 225                         bb_error_msg("invalid line %d: '%s'", linenum, line);
 226                         ret = EXIT_FAILURE;
 227                         continue;
 228                 }
 229
 230                 gid = (*group) ? get_ug_id(group, xgroup2gid) : getgid();
 231                 uid = (*user) ? get_ug_id(user, xuname2uid) : getuid();
 232                 /* We are already in the right root dir,
 233                  * so make absolute paths relative */
 234                 if ('/' == *full_name)
 235                         full_name++;
 236
 237                 if (type == 'd') {
 238                         bb_make_directory(full_name, mode | S_IFDIR, FILEUTILS_RECUR);
 239                         if (chown(full_name, uid, gid) == -1) {
 240  chown_fail:
 241                                 bb_perror_msg("line %d: can't chown %s", linenum, full_name);
 242                                 ret = EXIT_FAILURE;
 243                                 continue;
 244                         }
 245                         if (chmod(full_name, mode) < 0) {
 246  chmod_fail:
 247                                 bb_perror_msg("line %d: can't chmod %s", linenum, full_name);
 248                                 ret = EXIT_FAILURE;
 249                                 continue;
 250                         }
 251                 } else if (type == 'f') {
 252                         struct stat st;
 253                         if ((stat(full_name, &st) < 0 || !S_ISREG(st.st_mode))) {
 254                                 bb_perror_msg("line %d: regular file '%s' does not exist", linenum, full_name);
 255                                 ret = EXIT_FAILURE;
 256                                 continue;
 257                         }
 258                         if (chown(full_name, uid, gid) < 0)
 259                                 goto chown_fail;
 260                         if (chmod(full_name, mode) < 0)
 261                                 goto chmod_fail;
 262                 } else {
 263                         dev_t rdev;
 264                         unsigned i;
 265                         char *full_name_inc;
 266
 267                         if (type == 'p') {
 268                                 mode |= S_IFIFO;
 269                         } else if (type == 'c') {
 270                                 mode |= S_IFCHR;
 271                         } else if (type == 'b') {
 272                                 mode |= S_IFBLK;
 273                         } else {
 274                                 bb_error_msg("line %d: unsupported file type %c", linenum, type);
 275                                 ret = EXIT_FAILURE;
 276                                 continue;
 277                         }
 278
 279                         full_name_inc = xmalloc(strlen(full_name) + sizeof(int)*3 + 2);
 280                         if (count)
 281                                 count--;
 282                         for (i = start; i <= start + count; i++) {
 283                                 sprintf(full_name_inc, count ? "%s%u" : "%s", full_name, i);
 284                                 rdev = makedev(major, minor + (i - start) * increment);
 285                                 if (mknod(full_name_inc, mode, rdev) != 0
 286                                  && errno != EEXIST
 287                                 ) {
 288                                         bb_perror_msg("line %d: can't create node %s", linenum, full_name_inc);
 289                                         ret = EXIT_FAILURE;
 290                                 } else if (chown(full_name_inc, uid, gid) < 0) {
 291                                         bb_perror_msg("line %d: can't chown %s", linenum, full_name_inc);
 292                                         ret = EXIT_FAILURE;
 293                                 } else if (chmod(full_name_inc, mode) < 0) {
 294                                         bb_perror_msg("line %d: can't chmod %s", linenum, full_name_inc);
 295                                         ret = EXIT_FAILURE;
 296                                 }
 297                         }
 298                         free(full_name_inc);
 299                 }
 300         }
 301         if (ENABLE_FEATURE_CLEAN_UP)
 302                 config_close(parser);
 303
 304         return ret;
 305 }
 306
 307 #else
 308 # error makedevs configuration error, either leaf or table must be selected
 309 #endif