config.c

   1 /*
   2  * mdctl - manage Linux "md" devices aka RAID arrays.
   3  *
   4  * Copyright (C) 2001 Neil Brown <neilb@cse.unsw.edu.au>
   5  *
   6  *
   7  *    This program is free software; you can redistribute it and/or modify
   8  *    it under the terms of the GNU General Public License as published by
   9  *    the Free Software Foundation; either version 2 of the License, or
  10  *    (at your option) any later version.
  11  *
  12  *    This program is distributed in the hope that it will be useful,
  13  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *    GNU General Public License for more details.
  16  *
  17  *    You should have received a copy of the GNU General Public License
  18  *    along with this program; if not, write to the Free Software
  19  *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  *
  21  *    Author: Neil Brown
  22  *    Email: <neilb@cse.unsw.edu.au>
  23  *    Paper: Neil Brown
  24  *           School of Computer Science and Engineering
  25  *           The University of New South Wales
  26  *           Sydney, 2052
  27  *           Australia
  28  */
  29
  30 #include        "mdctl.h"
  31 #include        "dlink.h"
  32 #include        <glob.h>
  33 #include        <fnmatch.h>
  34
  35 /*
  36  * Read the config file
  37  *
  38  * conf_get_uuids gets a list of devicename+uuid pairs
  39  * conf_get_devs gets device names after expanding wildcards
  40  *
  41  * Each keeps the returned list and frees it when asked to make
  42  * a new list.
  43  *
  44  * The format of the config file needs to be fairly extensible.
  45  * Now, arrays only have names and uuids and devices merely are.
  46  * But later arrays might want names, and devices might want superblock
  47  * versions, and who knows what else.
  48  * I like free format, abhore backslash line continuation, adore
  49  *   indentation for structure and am ok about # comments.
  50  *
  51  * So, each line that isn't blank or a #comment must either start
  52  *  with a key word, and not be indented, or must start with a
  53  *  non-key-word and must be indented.
  54  *
  55  * Keywords are DEVICE and ARRAY
  56  * DEV{ICE} introduces some devices that might contain raid components.
  57  * e.g.
  58  *   DEV style=0 /dev/sda* /dev/hd*
  59  *   DEV style=1 /dev/sd[b-f]*
  60  * ARR{AY} describes an array giving md device and attributes like uuid=whatever
  61  * e.g.
  62  *   ARRAY /dev/md0 uuid=whatever name=something
  63  * Spaces separate words on each line.  Quoting, with "" or '' protects them,
  64  * but may not wrap over lines
  65  *
  66  */
  67
  68 char DefaultConfFile[] = "/etc/mdctl.conf";
  69
  70 char *keywords[] = { "device", "array", NULL };
  71
  72 /*
  73  * match_keyword returns an index into the keywords array, or -1 for no match
  74  * case is ignored, and at least three characters must be given
  75  */
  76
  77 int match_keyword(char *word)
  78 {
  79         int len = strlen(word);
  80         int n;
  81
  82         if (len < 3) return -1;
  83         for (n=0; keywords[n]; n++) {
  84                 if (strncasecmp(word, keywords[n], len)==0)
  85                         return n;
  86         }
  87         return -1;
  88 }
  89
  90 /* conf_word gets one word from the conf file.
  91  * if "allow_key", then accept words at the start of a line,
  92  * otherwise stop when such a word is found.
  93  * We assume that the file pointer is at the end of a word, so the
  94  * next character is a space, or a newline.  If not, it is the start of a line.
  95  */
  96
  97 char *conf_word(FILE *file, int allow_key)
  98 {
  99         int wsize = 100;
 100         int len = 0;
 101         int c;
 102         int quote;
 103         int wordfound = 0;
 104         char *word = malloc(wsize);
 105
 106         if (!word) abort();
 107
 108         while (wordfound==0) {
 109                 /* at the end of a word.. */
 110                 c = getc(file);
 111                 if (c == '#')
 112                         while (c != EOF && c != '\n')
 113                                 c = getc(file);
 114                 if (c == EOF) break;
 115                 if (c == '\n') continue;
 116
 117                 if (c != ' ' && c != '\t' && ! allow_key) {
 118                         ungetc(c, file);
 119                         break;
 120                 }
 121                 /* looks like it is safe to get a word here, if there is one */
 122                 quote = 0;
 123                 /* first, skip any spaces */
 124                 while (c == ' ' || c == '\t')
 125                         c = getc(file);
 126                 if (c != EOF && c != '\n' && c != '#') {
 127                         /* we really have a character of a word, so start saving it */
 128                         while (c != EOF && c != '\n' && (quote || (c!=' ' && c != '\t'))) {
 129                                 wordfound = 1;
 130                                 if (quote && c == quote) quote = 0;
 131                                 else if (quote == 0 && (c == '\'' || c == '"'))
 132                                         quote = c;
 133                                 else {
 134                                         if (len == wsize-1) {
 135                                                 wsize += 100;
 136                                                 word = realloc(word, wsize);
 137                                                 if (!word) abort();
 138                                         }
 139                                         word[len++] = c;
 140                                 }
 141                                 c = getc(file);
 142                         }
 143                 }
 144                 if (c != EOF) ungetc(c, file);
 145         }
 146         word[len] = 0;
 147 /*    printf("word is <%s>\n", word); */
 148         if (!wordfound) {
 149                 free(word);
 150                 word = NULL;
 151         }
 152         return word;
 153 }
 154
 155 /*
 156  * conf_line reads one logical line from the conffile.
 157  * It skips comments and continues until it finds a line that starts
 158  * with a non blank/comment.  This character is pushed back for the next call
 159  * A doubly linked list of words is returned.
 160  * the first word will be a keyword.  Other words will have had quotes removed.
 161  */
 162
 163 char *conf_line(FILE *file)
 164 {
 165         char *w;
 166         char *list;
 167
 168         w = conf_word(file, 1);
 169         if (w == NULL) return NULL;
 170
 171         list = dl_strdup(w);
 172         free(w);
 173         dl_init(list);
 174
 175         while ((w = conf_word(file,0))){
 176                 char *w2 = dl_strdup(w);
 177                 free(w);
 178                 dl_add(list, w2);
 179         }
 180 /*    printf("got a line\n");*/
 181         return list;
 182 }
 183
 184 void free_line(char *line)
 185 {
 186         char *w;
 187         for (w=dl_next(line); w != line; w=dl_next(line)) {
 188                 dl_del(w);
 189                 dl_free(w);
 190         }
 191         dl_free(line);
 192 }
 193
 194
 195 struct conf_dev {
 196     struct conf_dev *next;
 197     char *name;
 198 } *cdevlist = NULL;
 199
 200
 201
 202 int devline(char *line)
 203 {
 204         char *w;
 205         struct conf_dev *cd;
 206
 207         for (w=dl_next(line); w != line; w=dl_next(w)) {
 208                 if (w[0] == '/') {
 209                         cd = malloc(sizeof(*cd));
 210                         cd->name = strdup(w);
 211                         cd->next = cdevlist;
 212                         cdevlist = cd;
 213                 } else {
 214                         fprintf(stderr, Name ": unreconised word on DEVICE line: %s\n",
 215                                 w);
 216                 }
 217         }
 218 }
 219
 220 mddev_ident_t mddevlist = NULL;
 221 mddev_ident_t *mddevlp = &mddevlist;
 222
 223 void arrayline(char *line)
 224 {
 225         char *w;
 226
 227         struct mddev_ident_s mis;
 228         mddev_ident_t mi;
 229
 230         mis.uuid_set = 0;
 231         mis.super_minor = -1;
 232         mis.devices = NULL;
 233         mis.devname = NULL;
 234
 235         for (w=dl_next(line); w!=line; w=dl_next(w)) {
 236                 if (w[0] == '/') {
 237                         if (mis.devname)
 238                                 fprintf(stderr, Name ": only give one device per ARRAY line: %s and %s\n",
 239                                         mis.devname, w);
 240                         else mis.devname = w;
 241                 } else if (strncasecmp(w, "uuid=", 5)==0 ) {
 242                         if (mis.uuid_set)
 243                                 fprintf(stderr, Name ": only specify uuid once, %s ignored.\n",
 244                                         w);
 245                         else {
 246                                 if (parse_uuid(w+5, mis.uuid))
 247                                         mis.uuid_set = 1;
 248                                 else
 249                                         fprintf(stderr, Name ": bad uuid: %s\n", w);
 250                         }
 251                 } else if (strncasecmp(w, "super-minor=", 12)==0 ) {
 252                         if (mis.super_minor >= 0)
 253                                 fprintf(stderr, Name ": only specify super-minor once, %s ignored.\n",
 254                                         w);
 255                         else {
 256                                 char *endptr;
 257                                 mis.super_minor= strtol(w+12, &endptr, 10);
 258                                 if (w[12]==0 || endptr[0]!=0 || mis.super_minor < 0) {
 259                                         fprintf(stderr, Name ": invalid super-minor number: %s\n",
 260                                                 w);
 261                                         mis.super_minor = -1;
 262                                 }
 263                         }
 264                 } else if (strncasecmp(w, "devices=", 8 ) == 0 ) {
 265                         if (mis.devices)
 266                                 fprintf(stderr, Name ": only specify devices once (use a comma separated list). %s ignored\n",
 267                                         w);
 268                         else
 269                                 mis.devices = strdup(w+8);
 270                 } else if (strncasecmp(w, "spare-group=", 12) == 0 ) {
 271                         if (mis.spare_group)
 272                                 fprintf(stderr, Name ": only specify one spare group per array. %s ignored.\n",
 273                                         w);
 274                         else
 275                                 mis.spare_group = strdup(w+12);
 276                 } else {
 277                         fprintf(stderr, Name ": unrecognised word on ARRAY line: %s\n",
 278                                 w);
 279                 }
 280         }
 281         if (mis.devname == NULL)
 282                 fprintf(stderr, Name ": ARRAY line with a device\n");
 283         else if (mis.uuid_set == 0 && mis.devices == NULL && mis.super_minor < 0)
 284                 fprintf(stderr, Name ": ARRAY line %s has no identity information.\n", mis.devname);
 285         else {
 286                 mi = malloc(sizeof(*mi));
 287                 *mi = mis;
 288                 mi->devname = strdup(mis.devname);
 289                 mi->next = NULL;
 290                 *mddevlp = mi;
 291                 mddevlp = &mi->next;
 292         }
 293 }
 294
 295 int loaded = 0;
 296
 297 void load_conffile(char *conffile)
 298 {
 299         FILE *f;
 300         char *line;
 301
 302         if (loaded) return;
 303         if (conffile == NULL)
 304                 conffile = DefaultConfFile;
 305
 306         f = fopen(conffile, "r");
 307         if (f ==NULL)
 308                 return;
 309
 310         loaded = 1;
 311         while ((line=conf_line(f))) {
 312                 switch(match_keyword(line)) {
 313                 case 0: /* DEVICE */
 314                         devline(line);
 315                         break;
 316                 case 1:
 317                         arrayline(line);
 318                         break;
 319                 default:
 320                         fprintf(stderr, Name ": Unknown keyword %s\n", line);
 321                 }
 322                 free_line(line);
 323         }
 324
 325
 326 /*    printf("got file\n"); */
 327 }
 328
 329
 330 mddev_ident_t conf_get_ident(char *conffile, char *dev)
 331 {
 332         mddev_ident_t rv;
 333         load_conffile(conffile);
 334         rv = mddevlist;
 335         while (dev && rv && strcmp(dev, rv->devname)!=0)
 336                 rv = rv->next;
 337         return rv;
 338 }
 339
 340 mddev_dev_t conf_get_devs(char *conffile)
 341 {
 342         glob_t globbuf;
 343         struct conf_dev *cd;
 344         int flags = 0;
 345         static mddev_dev_t dlist = NULL;
 346         int i;
 347
 348         while (dlist) {
 349                 mddev_dev_t t = dlist;
 350                 dlist = dlist->next;
 351                 free(t->devname);
 352                 free(t);
 353         }
 354
 355         load_conffile(conffile);
 356
 357         for (cd=cdevlist; cd; cd=cd->next) {
 358                 glob(cd->name, flags, NULL, &globbuf);
 359                 flags |= GLOB_APPEND;
 360         }
 361
 362         for (i=0; i<globbuf.gl_pathc; i++) {
 363                 mddev_dev_t t = malloc(sizeof(*t));
 364                 t->devname = strdup(globbuf.gl_pathv[i]);
 365                 t->next = dlist;
 366                 dlist = t;
 367 /*      printf("one dev is %s\n", t->devname);*/
 368         }
 369         globfree(&globbuf);
 370
 371
 372         return dlist;
 373 }
 374
 375 int match_oneof(char *devices, char *devname)
 376 {
 377     /* check if one of the comma separated patterns in devices
 378      * matches devname
 379      */
 380
 381
 382     while (devices && *devices) {
 383         char patn[1024];
 384         char *p = devices;
 385         devices = strchr(devices, ',');
 386         if (!devices)
 387             devices = p + strlen(p);
 388         if (devices-p < 1024) {
 389                 strncpy(patn, p, devices-p);
 390                 patn[devices-p] = 0;
 391                 if (fnmatch(patn, devname, FNM_PATHNAME)==0)
 392                         return 1;
 393         }
 394         if (*devices == ',')
 395                 devices++;
 396     }
 397     return 0;
 398 }