tools/env/fw_env.c

   1 /*
   2  * (C) Copyright 2000-2008
   3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   4  *
   5  * See file CREDITS for list of people who contributed to this
   6  * project.
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as
  10  * published by the Free Software Foundation; either version 2 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  21  * MA 02111-1307 USA
  22  */
  23
  24 #include <errno.h>
  25 #include <fcntl.h>
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28 #include <stddef.h>
  29 #include <string.h>
  30 #include <sys/types.h>
  31 #include <sys/ioctl.h>
  32 #include <sys/stat.h>
  33 #include <unistd.h>
  34
  35 #ifdef MTD_OLD
  36 # include <linux/mtd/mtd.h>
  37 #else
  38 # define  __user        /* nothing */
  39 # include <mtd/mtd-user.h>
  40 #endif
  41
  42 #include "fw_env.h"
  43
  44 #define CMD_GETENV      "fw_printenv"
  45 #define CMD_SETENV      "fw_setenv"
  46
  47 typedef struct envdev_s {
  48         char devname[16];               /* Device name */
  49         ulong devoff;                   /* Device offset */
  50         ulong env_size;                 /* environment size */
  51         ulong erase_size;               /* device erase size */
  52 } envdev_t;
  53
  54 static envdev_t envdevices[2];
  55 static int curdev;
  56
  57 #define DEVNAME(i)    envdevices[(i)].devname
  58 #define DEVOFFSET(i)  envdevices[(i)].devoff
  59 #define ENVSIZE(i)    envdevices[(i)].env_size
  60 #define DEVESIZE(i)   envdevices[(i)].erase_size
  61
  62 #define CFG_ENV_SIZE ENVSIZE(curdev)
  63
  64 #define ENV_SIZE      getenvsize()
  65
  66 typedef struct environment_s {
  67         ulong crc;                      /* CRC32 over data bytes    */
  68         unsigned char flags;            /* active or obsolete */
  69         char *data;
  70 } env_t;
  71
  72 static env_t environment;
  73
  74 static int HaveRedundEnv = 0;
  75
  76 static unsigned char active_flag = 1;
  77 static unsigned char obsolete_flag = 0;
  78
  79
  80 #define XMK_STR(x)      #x
  81 #define MK_STR(x)       XMK_STR(x)
  82
  83 static char default_environment[] = {
  84 #if defined(CONFIG_BOOTARGS)
  85         "bootargs=" CONFIG_BOOTARGS "\0"
  86 #endif
  87 #if defined(CONFIG_BOOTCOMMAND)
  88         "bootcmd=" CONFIG_BOOTCOMMAND "\0"
  89 #endif
  90 #if defined(CONFIG_RAMBOOTCOMMAND)
  91         "ramboot=" CONFIG_RAMBOOTCOMMAND "\0"
  92 #endif
  93 #if defined(CONFIG_NFSBOOTCOMMAND)
  94         "nfsboot=" CONFIG_NFSBOOTCOMMAND "\0"
  95 #endif
  96 #if defined(CONFIG_BOOTDELAY) && (CONFIG_BOOTDELAY >= 0)
  97         "bootdelay=" MK_STR (CONFIG_BOOTDELAY) "\0"
  98 #endif
  99 #if defined(CONFIG_BAUDRATE) && (CONFIG_BAUDRATE >= 0)
 100         "baudrate=" MK_STR (CONFIG_BAUDRATE) "\0"
 101 #endif
 102 #ifdef  CONFIG_LOADS_ECHO
 103         "loads_echo=" MK_STR (CONFIG_LOADS_ECHO) "\0"
 104 #endif
 105 #ifdef  CONFIG_ETHADDR
 106         "ethaddr=" MK_STR (CONFIG_ETHADDR) "\0"
 107 #endif
 108 #ifdef  CONFIG_ETH1ADDR
 109         "eth1addr=" MK_STR (CONFIG_ETH1ADDR) "\0"
 110 #endif
 111 #ifdef  CONFIG_ETH2ADDR
 112         "eth2addr=" MK_STR (CONFIG_ETH2ADDR) "\0"
 113 #endif
 114 #ifdef  CONFIG_ETH3ADDR
 115         "eth3addr=" MK_STR (CONFIG_ETH3ADDR) "\0"
 116 #endif
 117 #ifdef  CONFIG_ETHPRIME
 118         "ethprime=" CONFIG_ETHPRIME "\0"
 119 #endif
 120 #ifdef  CONFIG_IPADDR
 121         "ipaddr=" MK_STR (CONFIG_IPADDR) "\0"
 122 #endif
 123 #ifdef  CONFIG_SERVERIP
 124         "serverip=" MK_STR (CONFIG_SERVERIP) "\0"
 125 #endif
 126 #ifdef  CFG_AUTOLOAD
 127         "autoload=" CFG_AUTOLOAD "\0"
 128 #endif
 129 #ifdef  CONFIG_ROOTPATH
 130         "rootpath=" MK_STR (CONFIG_ROOTPATH) "\0"
 131 #endif
 132 #ifdef  CONFIG_GATEWAYIP
 133         "gatewayip=" MK_STR (CONFIG_GATEWAYIP) "\0"
 134 #endif
 135 #ifdef  CONFIG_NETMASK
 136         "netmask=" MK_STR (CONFIG_NETMASK) "\0"
 137 #endif
 138 #ifdef  CONFIG_HOSTNAME
 139         "hostname=" MK_STR (CONFIG_HOSTNAME) "\0"
 140 #endif
 141 #ifdef  CONFIG_BOOTFILE
 142         "bootfile=" MK_STR (CONFIG_BOOTFILE) "\0"
 143 #endif
 144 #ifdef  CONFIG_LOADADDR
 145         "loadaddr=" MK_STR (CONFIG_LOADADDR) "\0"
 146 #endif
 147 #ifdef  CONFIG_PREBOOT
 148         "preboot=" CONFIG_PREBOOT "\0"
 149 #endif
 150 #ifdef  CONFIG_CLOCKS_IN_MHZ
 151         "clocks_in_mhz=" "1" "\0"
 152 #endif
 153 #if defined(CONFIG_PCI_BOOTDELAY) && (CONFIG_PCI_BOOTDELAY > 0)
 154         "pcidelay=" MK_STR (CONFIG_PCI_BOOTDELAY) "\0"
 155 #endif
 156 #ifdef  CONFIG_EXTRA_ENV_SETTINGS
 157         CONFIG_EXTRA_ENV_SETTINGS
 158 #endif
 159         "\0"                    /* Termimate env_t data with 2 NULs */
 160 };
 161
 162 static int flash_io (int mode);
 163 static char *envmatch (char * s1, char * s2);
 164 static int env_init (void);
 165 static int parse_config (void);
 166
 167 #if defined(CONFIG_FILE)
 168 static int get_config (char *);
 169 #endif
 170 static inline ulong getenvsize (void)
 171 {
 172         ulong rc = CFG_ENV_SIZE - sizeof (long);
 173
 174         if (HaveRedundEnv)
 175                 rc -= sizeof (char);
 176         return rc;
 177 }
 178
 179 /*
 180  * Search the environment for a variable.
 181  * Return the value, if found, or NULL, if not found.
 182  */
 183 char *fw_getenv (char *name)
 184 {
 185         char *env, *nxt;
 186
 187         if (env_init ())
 188                 return (NULL);
 189
 190         for (env = environment.data; *env; env = nxt + 1) {
 191                 char *val;
 192
 193                 for (nxt = env; *nxt; ++nxt) {
 194                         if (nxt >= &environment.data[ENV_SIZE]) {
 195                                 fprintf (stderr, "## Error: "
 196                                         "environment not terminated\n");
 197                                 return (NULL);
 198                         }
 199                 }
 200                 val = envmatch (name, env);
 201                 if (!val)
 202                         continue;
 203                 return (val);
 204         }
 205         return (NULL);
 206 }
 207
 208 /*
 209  * Print the current definition of one, or more, or all
 210  * environment variables
 211  */
 212 int fw_printenv (int argc, char *argv[])
 213 {
 214         char *env, *nxt;
 215         int i, n_flag;
 216         int rc = 0;
 217
 218         if (env_init ())
 219                 return (-1);
 220
 221         if (argc == 1) {                /* Print all env variables  */
 222                 for (env = environment.data; *env; env = nxt + 1) {
 223                         for (nxt = env; *nxt; ++nxt) {
 224                                 if (nxt >= &environment.data[ENV_SIZE]) {
 225                                         fprintf (stderr, "## Error: "
 226                                                 "environment not terminated\n");
 227                                         return (-1);
 228                                 }
 229                         }
 230
 231                         printf ("%s\n", env);
 232                 }
 233                 return (0);
 234         }
 235
 236         if (strcmp (argv[1], "-n") == 0) {
 237                 n_flag = 1;
 238                 ++argv;
 239                 --argc;
 240                 if (argc != 2) {
 241                         fprintf (stderr, "## Error: "
 242                                 "`-n' option requires exactly one argument\n");
 243                         return (-1);
 244                 }
 245         } else {
 246                 n_flag = 0;
 247         }
 248
 249         for (i = 1; i < argc; ++i) {    /* print single env variables   */
 250                 char *name = argv[i];
 251                 char *val = NULL;
 252
 253                 for (env = environment.data; *env; env = nxt + 1) {
 254
 255                         for (nxt = env; *nxt; ++nxt) {
 256                                 if (nxt >= &environment.data[ENV_SIZE]) {
 257                                         fprintf (stderr, "## Error: "
 258                                                 "environment not terminated\n");
 259                                         return (-1);
 260                                 }
 261                         }
 262                         val = envmatch (name, env);
 263                         if (val) {
 264                                 if (!n_flag) {
 265                                         fputs (name, stdout);
 266                                         putc ('=', stdout);
 267                                 }
 268                                 puts (val);
 269                                 break;
 270                         }
 271                 }
 272                 if (!val) {
 273                         fprintf (stderr, "## Error: \"%s\" not defined\n", name);
 274                         rc = -1;
 275                 }
 276         }
 277
 278         return (rc);
 279 }
 280
 281 /*
 282  * Deletes or sets environment variables. Returns errno style error codes:
 283  * 0      - OK
 284  * EINVAL - need at least 1 argument
 285  * EROFS  - certain variables ("ethaddr", "serial#") cannot be
 286  *          modified or deleted
 287  *
 288  */
 289 int fw_setenv (int argc, char *argv[])
 290 {
 291         int i, len;
 292         char *env, *nxt;
 293         char *oldval = NULL;
 294         char *name;
 295
 296         if (argc < 2) {
 297                 return (EINVAL);
 298         }
 299
 300         if (env_init ())
 301                 return (errno);
 302
 303         name = argv[1];
 304
 305         /*
 306          * search if variable with this name already exists
 307          */
 308         for (nxt = env = environment.data; *env; env = nxt + 1) {
 309                 for (nxt = env; *nxt; ++nxt) {
 310                         if (nxt >= &environment.data[ENV_SIZE]) {
 311                                 fprintf (stderr, "## Error: "
 312                                         "environment not terminated\n");
 313                                 return (EINVAL);
 314                         }
 315                 }
 316                 if ((oldval = envmatch (name, env)) != NULL)
 317                         break;
 318         }
 319
 320         /*
 321          * Delete any existing definition
 322          */
 323         if (oldval) {
 324                 /*
 325                  * Ethernet Address and serial# can be set only once
 326                  */
 327                 if ((strcmp (name, "ethaddr") == 0) ||
 328                         (strcmp (name, "serial#") == 0)) {
 329                         fprintf (stderr, "Can't overwrite \"%s\"\n", name);
 330                         return (EROFS);
 331                 }
 332
 333                 if (*++nxt == '\0') {
 334                         *env = '\0';
 335                 } else {
 336                         for (;;) {
 337                                 *env = *nxt++;
 338                                 if ((*env == '\0') && (*nxt == '\0'))
 339                                         break;
 340                                 ++env;
 341                         }
 342                 }
 343                 *++env = '\0';
 344         }
 345
 346         /* Delete only ? */
 347         if (argc < 3)
 348                 goto WRITE_FLASH;
 349
 350         /*
 351          * Append new definition at the end
 352          */
 353         for (env = environment.data; *env || *(env + 1); ++env);
 354         if (env > environment.data)
 355                 ++env;
 356         /*
 357          * Overflow when:
 358          * "name" + "=" + "val" +"\0\0"  > CFG_ENV_SIZE - (env-environment)
 359          */
 360         len = strlen (name) + 2;
 361         /* add '=' for first arg, ' ' for all others */
 362         for (i = 2; i < argc; ++i) {
 363                 len += strlen (argv[i]) + 1;
 364         }
 365         if (len > (&environment.data[ENV_SIZE] - env)) {
 366                 fprintf (stderr,
 367                         "Error: environment overflow, \"%s\" deleted\n",
 368                         name);
 369                 return (-1);
 370         }
 371         while ((*env = *name++) != '\0')
 372                 env++;
 373         for (i = 2; i < argc; ++i) {
 374                 char *val = argv[i];
 375
 376                 *env = (i == 2) ? '=' : ' ';
 377                 while ((*++env = *val++) != '\0');
 378         }
 379
 380         /* end is marked with double '\0' */
 381         *++env = '\0';
 382
 383   WRITE_FLASH:
 384
 385         /* Update CRC */
 386         environment.crc = crc32 (0, (uint8_t*) environment.data, ENV_SIZE);
 387
 388         /* write environment back to flash */
 389         if (flash_io (O_RDWR)) {
 390                 fprintf (stderr, "Error: can't write fw_env to flash\n");
 391                 return (-1);
 392         }
 393
 394         return (0);
 395 }
 396
 397 static int flash_io (int mode)
 398 {
 399         int fd, fdr, rc, otherdev, len, resid;
 400         erase_info_t erase;
 401         char *data = NULL;
 402
 403         if ((fd = open (DEVNAME (curdev), mode)) < 0) {
 404                 fprintf (stderr,
 405                         "Can't open %s: %s\n",
 406                         DEVNAME (curdev), strerror (errno));
 407                 return (-1);
 408         }
 409
 410         len = sizeof (environment.crc);
 411         if (HaveRedundEnv) {
 412                 len += sizeof (environment.flags);
 413         }
 414
 415         if (mode == O_RDWR) {
 416                 if (HaveRedundEnv) {
 417                         /* switch to next partition for writing */
 418                         otherdev = !curdev;
 419                         if ((fdr = open (DEVNAME (otherdev), mode)) < 0) {
 420                                 fprintf (stderr,
 421                                         "Can't open %s: %s\n",
 422                                         DEVNAME (otherdev),
 423                                         strerror (errno));
 424                                 return (-1);
 425                         }
 426                 } else {
 427                         otherdev = curdev;
 428                         fdr = fd;
 429                 }
 430                 printf ("Unlocking flash...\n");
 431                 erase.length = DEVESIZE (otherdev);
 432                 erase.start = DEVOFFSET (otherdev);
 433                 ioctl (fdr, MEMUNLOCK, &erase);
 434
 435                 if (HaveRedundEnv) {
 436                         erase.length = DEVESIZE (curdev);
 437                         erase.start = DEVOFFSET (curdev);
 438                         ioctl (fd, MEMUNLOCK, &erase);
 439                         environment.flags = active_flag;
 440                 }
 441
 442                 printf ("Done\n");
 443                 resid = DEVESIZE (otherdev) - CFG_ENV_SIZE;
 444                 if (resid) {
 445                         if ((data = malloc (resid)) == NULL) {
 446                                 fprintf (stderr,
 447                                         "Cannot malloc %d bytes: %s\n",
 448                                         resid,
 449                                         strerror (errno));
 450                                 return (-1);
 451                         }
 452                         if (lseek (fdr, DEVOFFSET (otherdev) + CFG_ENV_SIZE, SEEK_SET)
 453                                 == -1) {
 454                                 fprintf (stderr, "seek error on %s: %s\n",
 455                                         DEVNAME (otherdev),
 456                                         strerror (errno));
 457                                 return (-1);
 458                         }
 459                         if ((rc = read (fdr, data, resid)) != resid) {
 460                                 fprintf (stderr,
 461                                         "read error on %s: %s\n",
 462                                         DEVNAME (otherdev),
 463                                         strerror (errno));
 464                                 return (-1);
 465                         }
 466                 }
 467
 468                 printf ("Erasing old environment...\n");
 469
 470                 erase.length = DEVESIZE (otherdev);
 471                 erase.start = DEVOFFSET (otherdev);
 472                 if (ioctl (fdr, MEMERASE, &erase) != 0) {
 473                         fprintf (stderr, "MTD erase error on %s: %s\n",
 474                                 DEVNAME (otherdev),
 475                                 strerror (errno));
 476                         return (-1);
 477                 }
 478
 479                 printf ("Done\n");
 480
 481                 printf ("Writing environment to %s...\n", DEVNAME (otherdev));
 482                 if (lseek (fdr, DEVOFFSET (otherdev), SEEK_SET) == -1) {
 483                         fprintf (stderr,
 484                                 "seek error on %s: %s\n",
 485                                 DEVNAME (otherdev), strerror (errno));
 486                         return (-1);
 487                 }
 488                 if (write (fdr, &environment, len) != len) {
 489                         fprintf (stderr,
 490                                 "CRC write error on %s: %s\n",
 491                                 DEVNAME (otherdev), strerror (errno));
 492                         return (-1);
 493                 }
 494                 if (write (fdr, environment.data, ENV_SIZE) != ENV_SIZE) {
 495                         fprintf (stderr,
 496                                 "Write error on %s: %s\n",
 497                                 DEVNAME (otherdev), strerror (errno));
 498                         return (-1);
 499                 }
 500                 if (resid) {
 501                         if (write (fdr, data, resid) != resid) {
 502                                 fprintf (stderr,
 503                                         "write error on %s: %s\n",
 504                                         DEVNAME (curdev), strerror (errno));
 505                                 return (-1);
 506                         }
 507                         free (data);
 508                 }
 509                 if (HaveRedundEnv) {
 510                         /* change flag on current active env partition */
 511                         if (lseek (fd, DEVOFFSET (curdev) + sizeof (ulong), SEEK_SET)
 512                                 == -1) {
 513                                 fprintf (stderr, "seek error on %s: %s\n",
 514                                         DEVNAME (curdev), strerror (errno));
 515                                 return (-1);
 516                         }
 517                         if (write (fd, &obsolete_flag, sizeof (obsolete_flag)) !=
 518                                 sizeof (obsolete_flag)) {
 519                                 fprintf (stderr,
 520                                         "Write error on %s: %s\n",
 521                                         DEVNAME (curdev), strerror (errno));
 522                                 return (-1);
 523                         }
 524                 }
 525                 printf ("Done\n");
 526                 printf ("Locking ...\n");
 527                 erase.length = DEVESIZE (otherdev);
 528                 erase.start = DEVOFFSET (otherdev);
 529                 ioctl (fdr, MEMLOCK, &erase);
 530                 if (HaveRedundEnv) {
 531                         erase.length = DEVESIZE (curdev);
 532                         erase.start = DEVOFFSET (curdev);
 533                         ioctl (fd, MEMLOCK, &erase);
 534                         if (close (fdr)) {
 535                                 fprintf (stderr,
 536                                         "I/O error on %s: %s\n",
 537                                         DEVNAME (otherdev),
 538                                         strerror (errno));
 539                                 return (-1);
 540                         }
 541                 }
 542                 printf ("Done\n");
 543         } else {
 544
 545                 if (lseek (fd, DEVOFFSET (curdev), SEEK_SET) == -1) {
 546                         fprintf (stderr,
 547                                 "seek error on %s: %s\n",
 548                                 DEVNAME (curdev), strerror (errno));
 549                         return (-1);
 550                 }
 551                 if (read (fd, &environment, len) != len) {
 552                         fprintf (stderr,
 553                                 "CRC read error on %s: %s\n",
 554                                 DEVNAME (curdev), strerror (errno));
 555                         return (-1);
 556                 }
 557                 if ((rc = read (fd, environment.data, ENV_SIZE)) != ENV_SIZE) {
 558                         fprintf (stderr,
 559                                 "Read error on %s: %s\n",
 560                                 DEVNAME (curdev), strerror (errno));
 561                         return (-1);
 562                 }
 563         }
 564
 565         if (close (fd)) {
 566                 fprintf (stderr,
 567                         "I/O error on %s: %s\n",
 568                         DEVNAME (curdev), strerror (errno));
 569                 return (-1);
 570         }
 571
 572         /* everything ok */
 573         return (0);
 574 }
 575
 576 /*
 577  * s1 is either a simple 'name', or a 'name=value' pair.
 578  * s2 is a 'name=value' pair.
 579  * If the names match, return the value of s2, else NULL.
 580  */
 581
 582 static char *envmatch (char * s1, char * s2)
 583 {
 584
 585         while (*s1 == *s2++)
 586                 if (*s1++ == '=')
 587                         return (s2);
 588         if (*s1 == '\0' && *(s2 - 1) == '=')
 589                 return (s2);
 590         return (NULL);
 591 }
 592
 593 /*
 594  * Prevent confusion if running from erased flash memory
 595  */
 596 static int env_init (void)
 597 {
 598         int crc1, crc1_ok;
 599         char *addr1;
 600
 601         int crc2, crc2_ok;
 602         char flag1, flag2, *addr2;
 603
 604         if (parse_config ())            /* should fill envdevices */
 605                 return 1;
 606
 607         if ((addr1 = calloc (1, ENV_SIZE)) == NULL) {
 608                 fprintf (stderr,
 609                         "Not enough memory for environment (%ld bytes)\n",
 610                         ENV_SIZE);
 611                 return (errno);
 612         }
 613
 614         /* read environment from FLASH to local buffer */
 615         environment.data = addr1;
 616         curdev = 0;
 617         if (flash_io (O_RDONLY)) {
 618                 return (errno);
 619         }
 620
 621         crc1_ok = ((crc1 = crc32 (0, (uint8_t *) environment.data, ENV_SIZE))
 622                            == environment.crc);
 623         if (!HaveRedundEnv) {
 624                 if (!crc1_ok) {
 625                         fprintf (stderr,
 626                                 "Warning: Bad CRC, using default environment\n");
 627                         memcpy(environment.data, default_environment, sizeof default_environment);
 628                 }
 629         } else {
 630                 flag1 = environment.flags;
 631
 632                 curdev = 1;
 633                 if ((addr2 = calloc (1, ENV_SIZE)) == NULL) {
 634                         fprintf (stderr,
 635                                 "Not enough memory for environment (%ld bytes)\n",
 636                                 ENV_SIZE);
 637                         return (errno);
 638                 }
 639                 environment.data = addr2;
 640
 641                 if (flash_io (O_RDONLY)) {
 642                         return (errno);
 643                 }
 644
 645                 crc2_ok = ((crc2 = crc32 (0, (uint8_t *) environment.data, ENV_SIZE))
 646                                    == environment.crc);
 647                 flag2 = environment.flags;
 648
 649                 if (crc1_ok && !crc2_ok) {
 650                         environment.data = addr1;
 651                         environment.flags = flag1;
 652                         environment.crc = crc1;
 653                         curdev = 0;
 654                         free (addr2);
 655                 } else if (!crc1_ok && crc2_ok) {
 656                         environment.data = addr2;
 657                         environment.flags = flag2;
 658                         environment.crc = crc2;
 659                         curdev = 1;
 660                         free (addr1);
 661                 } else if (!crc1_ok && !crc2_ok) {
 662                         fprintf (stderr,
 663                                 "Warning: Bad CRC, using default environment\n");
 664                         memcpy(environment.data, default_environment, sizeof default_environment);
 665                         curdev = 0;
 666                         free (addr1);
 667                 } else if (flag1 == active_flag && flag2 == obsolete_flag) {
 668                         environment.data = addr1;
 669                         environment.flags = flag1;
 670                         environment.crc = crc1;
 671                         curdev = 0;
 672                         free (addr2);
 673                 } else if (flag1 == obsolete_flag && flag2 == active_flag) {
 674                         environment.data = addr2;
 675                         environment.flags = flag2;
 676                         environment.crc = crc2;
 677                         curdev = 1;
 678                         free (addr1);
 679                 } else if (flag1 == flag2) {
 680                         environment.data = addr1;
 681                         environment.flags = flag1;
 682                         environment.crc = crc1;
 683                         curdev = 0;
 684                         free (addr2);
 685                 } else if (flag1 == 0xFF) {
 686                         environment.data = addr1;
 687                         environment.flags = flag1;
 688                         environment.crc = crc1;
 689                         curdev = 0;
 690                         free (addr2);
 691                 } else if (flag2 == 0xFF) {
 692                         environment.data = addr2;
 693                         environment.flags = flag2;
 694                         environment.crc = crc2;
 695                         curdev = 1;
 696                         free (addr1);
 697                 }
 698         }
 699         return (0);
 700 }
 701
 702
 703 static int parse_config ()
 704 {
 705         struct stat st;
 706
 707 #if defined(CONFIG_FILE)
 708         /* Fills in DEVNAME(), ENVSIZE(), DEVESIZE(). Or don't. */
 709         if (get_config (CONFIG_FILE)) {
 710                 fprintf (stderr,
 711                         "Cannot parse config file: %s\n", strerror (errno));
 712                 return 1;
 713         }
 714 #else
 715         strcpy (DEVNAME (0), DEVICE1_NAME);
 716         DEVOFFSET (0) = DEVICE1_OFFSET;
 717         ENVSIZE (0) = ENV1_SIZE;
 718         DEVESIZE (0) = DEVICE1_ESIZE;
 719 #ifdef HAVE_REDUND
 720         strcpy (DEVNAME (1), DEVICE2_NAME);
 721         DEVOFFSET (1) = DEVICE2_OFFSET;
 722         ENVSIZE (1) = ENV2_SIZE;
 723         DEVESIZE (1) = DEVICE2_ESIZE;
 724         HaveRedundEnv = 1;
 725 #endif
 726 #endif
 727         if (stat (DEVNAME (0), &st)) {
 728                 fprintf (stderr,
 729                         "Cannot access MTD device %s: %s\n",
 730                         DEVNAME (0), strerror (errno));
 731                 return 1;
 732         }
 733
 734         if (HaveRedundEnv && stat (DEVNAME (1), &st)) {
 735                 fprintf (stderr,
 736                         "Cannot access MTD device %s: %s\n",
 737                         DEVNAME (1), strerror (errno));
 738                 return 1;
 739         }
 740         return 0;
 741 }
 742
 743 #if defined(CONFIG_FILE)
 744 static int get_config (char *fname)
 745 {
 746         FILE *fp;
 747         int i = 0;
 748         int rc;
 749         char dump[128];
 750
 751         if ((fp = fopen (fname, "r")) == NULL) {
 752                 return 1;
 753         }
 754
 755         while ((i < 2) && ((rc = fscanf (fp, "%s %lx %lx %lx",
 756                                   DEVNAME (i),
 757                                   &DEVOFFSET (i),
 758                                   &ENVSIZE (i),
 759                                   &DEVESIZE (i)  )) != EOF)) {
 760
 761                 /* Skip incomplete conversions and comment strings */
 762                 if ((rc < 3) || (*DEVNAME (i) == '#')) {
 763                         fgets (dump, sizeof (dump), fp);        /* Consume till end */
 764                         continue;
 765                 }
 766
 767                 i++;
 768         }
 769         fclose (fp);
 770
 771         HaveRedundEnv = i - 1;
 772         if (!i) {                       /* No valid entries found */
 773                 errno = EINVAL;
 774                 return 1;
 775         } else
 776                 return 0;
 777 }
 778 #endif