xref: /openbmc/u-boot/tools/env/fw_env.c (revision 8e6f1a8e)
1 /*
2  * (C) Copyright 2000-2003
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 #include <linux/mtd/mtd.h>
35 #include "fw_env.h"
36 
37 typedef unsigned char uchar;
38 
39 #define	CMD_GETENV	"fw_printenv"
40 #define	CMD_SETENV	"fw_setenv"
41 
42 typedef struct envdev_s {
43 	uchar devname[16];		/* Device name */
44 	ulong devoff;			/* Device offset */
45 	ulong env_size;			/* environment size */
46 	ulong erase_size;		/* device erase size */
47 } envdev_t;
48 
49 static envdev_t envdevices[2];
50 static int curdev;
51 
52 #define DEVNAME(i)    envdevices[(i)].devname
53 #define DEVOFFSET(i)  envdevices[(i)].devoff
54 #define ENVSIZE(i)    envdevices[(i)].env_size
55 #define DEVESIZE(i)   envdevices[(i)].erase_size
56 
57 #define CFG_ENV_SIZE ENVSIZE(curdev)
58 
59 #define ENV_SIZE      getenvsize()
60 
61 typedef struct environment_s {
62 	ulong crc;			/* CRC32 over data bytes    */
63 	uchar flags;			/* active or obsolete */
64 	uchar *data;
65 } env_t;
66 
67 static env_t environment;
68 
69 static int HaveRedundEnv = 0;
70 
71 static uchar active_flag = 1;
72 static uchar obsolete_flag = 0;
73 
74 
75 #define XMK_STR(x)	#x
76 #define MK_STR(x)	XMK_STR(x)
77 
78 static uchar default_environment[] = {
79 #if defined(CONFIG_BOOTARGS)
80 	"bootargs=" CONFIG_BOOTARGS "\0"
81 #endif
82 #if defined(CONFIG_BOOTCOMMAND)
83 	"bootcmd=" CONFIG_BOOTCOMMAND "\0"
84 #endif
85 #if defined(CONFIG_RAMBOOTCOMMAND)
86 	"ramboot=" CONFIG_RAMBOOTCOMMAND "\0"
87 #endif
88 #if defined(CONFIG_NFSBOOTCOMMAND)
89 	"nfsboot=" CONFIG_NFSBOOTCOMMAND "\0"
90 #endif
91 #if defined(CONFIG_BOOTDELAY) && (CONFIG_BOOTDELAY >= 0)
92 	"bootdelay=" MK_STR (CONFIG_BOOTDELAY) "\0"
93 #endif
94 #if defined(CONFIG_BAUDRATE) && (CONFIG_BAUDRATE >= 0)
95 	"baudrate=" MK_STR (CONFIG_BAUDRATE) "\0"
96 #endif
97 #ifdef	CONFIG_LOADS_ECHO
98 	"loads_echo=" MK_STR (CONFIG_LOADS_ECHO) "\0"
99 #endif
100 #ifdef	CONFIG_ETHADDR
101 	"ethaddr=" MK_STR (CONFIG_ETHADDR) "\0"
102 #endif
103 #ifdef	CONFIG_ETH1ADDR
104 	"eth1addr=" MK_STR (CONFIG_ETH1ADDR) "\0"
105 #endif
106 #ifdef	CONFIG_ETH2ADDR
107 	"eth2addr=" MK_STR (CONFIG_ETH2ADDR) "\0"
108 #endif
109 #ifdef	CONFIG_ETH3ADDR
110 	"eth3addr=" MK_STR (CONFIG_ETH3ADDR) "\0"
111 #endif
112 #ifdef	CONFIG_ETHPRIME
113 	"ethprime=" CONFIG_ETHPRIME "\0"
114 #endif
115 #ifdef	CONFIG_IPADDR
116 	"ipaddr=" MK_STR (CONFIG_IPADDR) "\0"
117 #endif
118 #ifdef	CONFIG_SERVERIP
119 	"serverip=" MK_STR (CONFIG_SERVERIP) "\0"
120 #endif
121 #ifdef	CFG_AUTOLOAD
122 	"autoload=" CFG_AUTOLOAD "\0"
123 #endif
124 #ifdef	CONFIG_ROOTPATH
125 	"rootpath=" MK_STR (CONFIG_ROOTPATH) "\0"
126 #endif
127 #ifdef	CONFIG_GATEWAYIP
128 	"gatewayip=" MK_STR (CONFIG_GATEWAYIP) "\0"
129 #endif
130 #ifdef	CONFIG_NETMASK
131 	"netmask=" MK_STR (CONFIG_NETMASK) "\0"
132 #endif
133 #ifdef	CONFIG_HOSTNAME
134 	"hostname=" MK_STR (CONFIG_HOSTNAME) "\0"
135 #endif
136 #ifdef	CONFIG_BOOTFILE
137 	"bootfile=" MK_STR (CONFIG_BOOTFILE) "\0"
138 #endif
139 #ifdef	CONFIG_LOADADDR
140 	"loadaddr=" MK_STR (CONFIG_LOADADDR) "\0"
141 #endif
142 #ifdef	CONFIG_PREBOOT
143 	"preboot=" CONFIG_PREBOOT "\0"
144 #endif
145 #ifdef	CONFIG_CLOCKS_IN_MHZ
146 	"clocks_in_mhz=" "1" "\0"
147 #endif
148 #if defined(CONFIG_PCI_BOOTDELAY) && (CONFIG_PCI_BOOTDELAY > 0)
149 	"pcidelay=" MK_STR (CONFIG_PCI_BOOTDELAY) "\0"
150 #endif
151 #ifdef  CONFIG_EXTRA_ENV_SETTINGS
152 	CONFIG_EXTRA_ENV_SETTINGS
153 #endif
154 	"\0"			/* Termimate env_t data with 2 NULs */
155 };
156 
157 static int flash_io (int mode);
158 static uchar *envmatch (uchar * s1, uchar * s2);
159 static int env_init (void);
160 static int parse_config (void);
161 
162 #if defined(CONFIG_FILE)
163 static int get_config (char *);
164 #endif
165 static inline ulong getenvsize (void)
166 {
167 	ulong rc = CFG_ENV_SIZE - sizeof (long);
168 
169 	if (HaveRedundEnv)
170 		rc -= sizeof (char);
171 	return rc;
172 }
173 
174 /*
175  * Search the environment for a variable.
176  * Return the value, if found, or NULL, if not found.
177  */
178 unsigned char *fw_getenv (unsigned char *name)
179 {
180 	uchar *env, *nxt;
181 
182 	if (env_init ())
183 		return (NULL);
184 
185 	for (env = environment.data; *env; env = nxt + 1) {
186 		uchar *val;
187 
188 		for (nxt = env; *nxt; ++nxt) {
189 			if (nxt >= &environment.data[ENV_SIZE]) {
190 				fprintf (stderr, "## Error: "
191 					"environment not terminated\n");
192 				return (NULL);
193 			}
194 		}
195 		val = envmatch (name, env);
196 		if (!val)
197 			continue;
198 		return (val);
199 	}
200 	return (NULL);
201 }
202 
203 /*
204  * Print the current definition of one, or more, or all
205  * environment variables
206  */
207 void fw_printenv (int argc, char *argv[])
208 {
209 	uchar *env, *nxt;
210 	int i, n_flag;
211 
212 	if (env_init ())
213 		return;
214 
215 	if (argc == 1) {		/* Print all env variables  */
216 		for (env = environment.data; *env; env = nxt + 1) {
217 			for (nxt = env; *nxt; ++nxt) {
218 				if (nxt >= &environment.data[ENV_SIZE]) {
219 					fprintf (stderr, "## Error: "
220 						"environment not terminated\n");
221 					return;
222 				}
223 			}
224 
225 			printf ("%s\n", env);
226 		}
227 		return;
228 	}
229 
230 	if (strcmp (argv[1], "-n") == 0) {
231 		n_flag = 1;
232 		++argv;
233 		--argc;
234 		if (argc != 2) {
235 			fprintf (stderr, "## Error: "
236 				"`-n' option requires exactly one argument\n");
237 			return;
238 		}
239 	} else {
240 		n_flag = 0;
241 	}
242 
243 	for (i = 1; i < argc; ++i) {	/* print single env variables   */
244 		uchar *name = argv[i];
245 		uchar *val = NULL;
246 
247 		for (env = environment.data; *env; env = nxt + 1) {
248 
249 			for (nxt = env; *nxt; ++nxt) {
250 				if (nxt >= &environment.data[ENV_SIZE]) {
251 					fprintf (stderr, "## Error: "
252 						"environment not terminated\n");
253 					return;
254 				}
255 			}
256 			val = envmatch (name, env);
257 			if (val) {
258 				if (!n_flag) {
259 					fputs (name, stdout);
260 					putc ('=', stdout);
261 				}
262 				puts (val);
263 				break;
264 			}
265 		}
266 		if (!val)
267 			fprintf (stderr, "## Error: \"%s\" not defined\n", name);
268 	}
269 }
270 
271 /*
272  * Deletes or sets environment variables. Returns errno style error codes:
273  * 0	  - OK
274  * EINVAL - need at least 1 argument
275  * EROFS  - certain variables ("ethaddr", "serial#") cannot be
276  *	    modified or deleted
277  *
278  */
279 int fw_setenv (int argc, char *argv[])
280 {
281 	int i, len;
282 	uchar *env, *nxt;
283 	uchar *oldval = NULL;
284 	uchar *name;
285 
286 	if (argc < 2) {
287 		return (EINVAL);
288 	}
289 
290 	if (env_init ())
291 		return (errno);
292 
293 	name = argv[1];
294 
295 	/*
296 	 * search if variable with this name already exists
297 	 */
298 	for (nxt = env = environment.data; *env; env = nxt + 1) {
299 		for (nxt = env; *nxt; ++nxt) {
300 			if (nxt >= &environment.data[ENV_SIZE]) {
301 				fprintf (stderr, "## Error: "
302 					"environment not terminated\n");
303 				return (EINVAL);
304 			}
305 		}
306 		if ((oldval = envmatch (name, env)) != NULL)
307 			break;
308 	}
309 
310 	/*
311 	 * Delete any existing definition
312 	 */
313 	if (oldval) {
314 		/*
315 		 * Ethernet Address and serial# can be set only once
316 		 */
317 		if ((strcmp (name, "ethaddr") == 0) ||
318 			(strcmp (name, "serial#") == 0)) {
319 			fprintf (stderr, "Can't overwrite \"%s\"\n", name);
320 			return (EROFS);
321 		}
322 
323 		if (*++nxt == '\0') {
324 			*env = '\0';
325 		} else {
326 			for (;;) {
327 				*env = *nxt++;
328 				if ((*env == '\0') && (*nxt == '\0'))
329 					break;
330 				++env;
331 			}
332 		}
333 		*++env = '\0';
334 	}
335 
336 	/* Delete only ? */
337 	if (argc < 3)
338 		goto WRITE_FLASH;
339 
340 	/*
341 	 * Append new definition at the end
342 	 */
343 	for (env = environment.data; *env || *(env + 1); ++env);
344 	if (env > environment.data)
345 		++env;
346 	/*
347 	 * Overflow when:
348 	 * "name" + "=" + "val" +"\0\0"  > CFG_ENV_SIZE - (env-environment)
349 	 */
350 	len = strlen (name) + 2;
351 	/* add '=' for first arg, ' ' for all others */
352 	for (i = 2; i < argc; ++i) {
353 		len += strlen (argv[i]) + 1;
354 	}
355 	if (len > (&environment.data[ENV_SIZE] - env)) {
356 		fprintf (stderr,
357 			"Error: environment overflow, \"%s\" deleted\n",
358 			name);
359 		return (-1);
360 	}
361 	while ((*env = *name++) != '\0')
362 		env++;
363 	for (i = 2; i < argc; ++i) {
364 		uchar *val = argv[i];
365 
366 		*env = (i == 2) ? '=' : ' ';
367 		while ((*++env = *val++) != '\0');
368 	}
369 
370 	/* end is marked with double '\0' */
371 	*++env = '\0';
372 
373   WRITE_FLASH:
374 
375 	/* Update CRC */
376 	environment.crc = crc32 (0, environment.data, ENV_SIZE);
377 
378 	/* write environment back to flash */
379 	if (flash_io (O_RDWR)) {
380 		fprintf (stderr, "Error: can't write fw_env to flash\n");
381 		return (-1);
382 	}
383 
384 	return (0);
385 }
386 
387 static int flash_io (int mode)
388 {
389 	int fd, fdr, rc, otherdev, len, resid;
390 	erase_info_t erase;
391 	char *data = NULL;
392 
393 	if ((fd = open (DEVNAME (curdev), mode)) < 0) {
394 		fprintf (stderr,
395 			"Can't open %s: %s\n",
396 			DEVNAME (curdev), strerror (errno));
397 		return (-1);
398 	}
399 
400 	len = sizeof (environment.crc);
401 	if (HaveRedundEnv) {
402 		len += sizeof (environment.flags);
403 	}
404 
405 	if (mode == O_RDWR) {
406 		if (HaveRedundEnv) {
407 			/* switch to next partition for writing */
408 			otherdev = !curdev;
409 			if ((fdr = open (DEVNAME (otherdev), mode)) < 0) {
410 				fprintf (stderr,
411 					"Can't open %s: %s\n",
412 					DEVNAME (otherdev),
413 					strerror (errno));
414 				return (-1);
415 			}
416 		} else {
417 			otherdev = curdev;
418 			fdr = fd;
419 		}
420 		printf ("Unlocking flash...\n");
421 		erase.length = DEVESIZE (otherdev);
422 		erase.start = DEVOFFSET (otherdev);
423 		ioctl (fdr, MEMUNLOCK, &erase);
424 
425 		if (HaveRedundEnv) {
426 			erase.length = DEVESIZE (curdev);
427 			erase.start = DEVOFFSET (curdev);
428 			ioctl (fd, MEMUNLOCK, &erase);
429 			environment.flags = active_flag;
430 		}
431 
432 		printf ("Done\n");
433 		resid = DEVESIZE (otherdev) - CFG_ENV_SIZE;
434 		if (resid) {
435 			if ((data = malloc (resid)) == NULL) {
436 				fprintf (stderr,
437 					"Cannot malloc %d bytes: %s\n",
438 					resid,
439 					strerror (errno));
440 				return (-1);
441 			}
442 			if (lseek (fdr, DEVOFFSET (otherdev) + CFG_ENV_SIZE, SEEK_SET)
443 				== -1) {
444 				fprintf (stderr, "seek error on %s: %s\n",
445 					DEVNAME (otherdev),
446 					strerror (errno));
447 				return (-1);
448 			}
449 			if ((rc = read (fdr, data, resid)) != resid) {
450 				fprintf (stderr,
451 					"read error on %s: %s\n",
452 					DEVNAME (otherdev),
453 					strerror (errno));
454 				return (-1);
455 			}
456 		}
457 
458 		printf ("Erasing old environment...\n");
459 
460 		erase.length = DEVESIZE (otherdev);
461 		erase.start = DEVOFFSET (otherdev);
462 		if (ioctl (fdr, MEMERASE, &erase) != 0) {
463 			fprintf (stderr, "MTD erase error on %s: %s\n",
464 				DEVNAME (otherdev),
465 				strerror (errno));
466 			return (-1);
467 		}
468 
469 		printf ("Done\n");
470 
471 		printf ("Writing environment to %s...\n", DEVNAME (otherdev));
472 		if (lseek (fdr, DEVOFFSET (otherdev), SEEK_SET) == -1) {
473 			fprintf (stderr,
474 				"seek error on %s: %s\n",
475 				DEVNAME (otherdev), strerror (errno));
476 			return (-1);
477 		}
478 		if (write (fdr, &environment, len) != len) {
479 			fprintf (stderr,
480 				"CRC write error on %s: %s\n",
481 				DEVNAME (otherdev), strerror (errno));
482 			return (-1);
483 		}
484 		if (write (fdr, environment.data, ENV_SIZE) != ENV_SIZE) {
485 			fprintf (stderr,
486 				"Write error on %s: %s\n",
487 				DEVNAME (otherdev), strerror (errno));
488 			return (-1);
489 		}
490 		if (resid) {
491 			if (write (fdr, data, resid) != resid) {
492 				fprintf (stderr,
493 					"write error on %s: %s\n",
494 					DEVNAME (curdev), strerror (errno));
495 				return (-1);
496 			}
497 			free (data);
498 		}
499 		if (HaveRedundEnv) {
500 			/* change flag on current active env partition */
501 			if (lseek (fd, DEVOFFSET (curdev) + sizeof (ulong), SEEK_SET)
502 				== -1) {
503 				fprintf (stderr, "seek error on %s: %s\n",
504 					DEVNAME (curdev), strerror (errno));
505 				return (-1);
506 			}
507 			if (write (fd, &obsolete_flag, sizeof (obsolete_flag)) !=
508 				sizeof (obsolete_flag)) {
509 				fprintf (stderr,
510 					"Write error on %s: %s\n",
511 					DEVNAME (curdev), strerror (errno));
512 				return (-1);
513 			}
514 		}
515 		printf ("Done\n");
516 		printf ("Locking ...\n");
517 		erase.length = DEVESIZE (otherdev);
518 		erase.start = DEVOFFSET (otherdev);
519 		ioctl (fdr, MEMLOCK, &erase);
520 		if (HaveRedundEnv) {
521 			erase.length = DEVESIZE (curdev);
522 			erase.start = DEVOFFSET (curdev);
523 			ioctl (fd, MEMLOCK, &erase);
524 			if (close (fdr)) {
525 				fprintf (stderr,
526 					"I/O error on %s: %s\n",
527 					DEVNAME (otherdev),
528 					strerror (errno));
529 				return (-1);
530 			}
531 		}
532 		printf ("Done\n");
533 	} else {
534 
535 		if (lseek (fd, DEVOFFSET (curdev), SEEK_SET) == -1) {
536 			fprintf (stderr,
537 				"seek error on %s: %s\n",
538 				DEVNAME (curdev), strerror (errno));
539 			return (-1);
540 		}
541 		if (read (fd, &environment, len) != len) {
542 			fprintf (stderr,
543 				"CRC read error on %s: %s\n",
544 				DEVNAME (curdev), strerror (errno));
545 			return (-1);
546 		}
547 		if ((rc = read (fd, environment.data, ENV_SIZE)) != ENV_SIZE) {
548 			fprintf (stderr,
549 				"Read error on %s: %s\n",
550 				DEVNAME (curdev), strerror (errno));
551 			return (-1);
552 		}
553 	}
554 
555 	if (close (fd)) {
556 		fprintf (stderr,
557 			"I/O error on %s: %s\n",
558 			DEVNAME (curdev), strerror (errno));
559 		return (-1);
560 	}
561 
562 	/* everything ok */
563 	return (0);
564 }
565 
566 /*
567  * s1 is either a simple 'name', or a 'name=value' pair.
568  * s2 is a 'name=value' pair.
569  * If the names match, return the value of s2, else NULL.
570  */
571 
572 static uchar *envmatch (uchar * s1, uchar * s2)
573 {
574 
575 	while (*s1 == *s2++)
576 		if (*s1++ == '=')
577 			return (s2);
578 	if (*s1 == '\0' && *(s2 - 1) == '=')
579 		return (s2);
580 	return (NULL);
581 }
582 
583 /*
584  * Prevent confusion if running from erased flash memory
585  */
586 static int env_init (void)
587 {
588 	int crc1, crc1_ok;
589 	uchar *addr1;
590 
591 	int crc2, crc2_ok;
592 	uchar flag1, flag2, *addr2;
593 
594 	if (parse_config ())		/* should fill envdevices */
595 		return 1;
596 
597 	if ((addr1 = calloc (1, ENV_SIZE)) == NULL) {
598 		fprintf (stderr,
599 			"Not enough memory for environment (%ld bytes)\n",
600 			ENV_SIZE);
601 		return (errno);
602 	}
603 
604 	/* read environment from FLASH to local buffer */
605 	environment.data = addr1;
606 	curdev = 0;
607 	if (flash_io (O_RDONLY)) {
608 		return (errno);
609 	}
610 
611 	crc1_ok = ((crc1 = crc32 (0, environment.data, ENV_SIZE))
612 			   == environment.crc);
613 	if (!HaveRedundEnv) {
614 		if (!crc1_ok) {
615 			fprintf (stderr,
616 				"Warning: Bad CRC, using default environment\n");
617 			environment.data = default_environment;
618 			free (addr1);
619 		}
620 	} else {
621 		flag1 = environment.flags;
622 
623 		curdev = 1;
624 		if ((addr2 = calloc (1, ENV_SIZE)) == NULL) {
625 			fprintf (stderr,
626 				"Not enough memory for environment (%ld bytes)\n",
627 				ENV_SIZE);
628 			return (errno);
629 		}
630 		environment.data = addr2;
631 
632 		if (flash_io (O_RDONLY)) {
633 			return (errno);
634 		}
635 
636 		crc2_ok = ((crc2 = crc32 (0, environment.data, ENV_SIZE))
637 				   == environment.crc);
638 		flag2 = environment.flags;
639 
640 		if (crc1_ok && !crc2_ok) {
641 			environment.data = addr1;
642 			environment.flags = flag1;
643 			environment.crc = crc1;
644 			curdev = 0;
645 			free (addr2);
646 		} else if (!crc1_ok && crc2_ok) {
647 			environment.data = addr2;
648 			environment.flags = flag2;
649 			environment.crc = crc2;
650 			curdev = 1;
651 			free (addr1);
652 		} else if (!crc1_ok && !crc2_ok) {
653 			fprintf (stderr,
654 				"Warning: Bad CRC, using default environment\n");
655 			environment.data = default_environment;
656 			curdev = 0;
657 			free (addr2);
658 			free (addr1);
659 		} else if (flag1 == active_flag && flag2 == obsolete_flag) {
660 			environment.data = addr1;
661 			environment.flags = flag1;
662 			environment.crc = crc1;
663 			curdev = 0;
664 			free (addr2);
665 		} else if (flag1 == obsolete_flag && flag2 == active_flag) {
666 			environment.data = addr2;
667 			environment.flags = flag2;
668 			environment.crc = crc2;
669 			curdev = 1;
670 			free (addr1);
671 		} else if (flag1 == flag2) {
672 			environment.data = addr1;
673 			environment.flags = flag1;
674 			environment.crc = crc1;
675 			curdev = 0;
676 			free (addr2);
677 		} else if (flag1 == 0xFF) {
678 			environment.data = addr1;
679 			environment.flags = flag1;
680 			environment.crc = crc1;
681 			curdev = 0;
682 			free (addr2);
683 		} else if (flag2 == 0xFF) {
684 			environment.data = addr2;
685 			environment.flags = flag2;
686 			environment.crc = crc2;
687 			curdev = 1;
688 			free (addr1);
689 		}
690 	}
691 	return (0);
692 }
693 
694 
695 static int parse_config ()
696 {
697 	struct stat st;
698 
699 #if defined(CONFIG_FILE)
700 	/* Fills in DEVNAME(), ENVSIZE(), DEVESIZE(). Or don't. */
701 	if (get_config (CONFIG_FILE)) {
702 		fprintf (stderr,
703 			"Cannot parse config file: %s\n", strerror (errno));
704 		return 1;
705 	}
706 #else
707 	strcpy (DEVNAME (0), DEVICE1_NAME);
708 	DEVOFFSET (0) = DEVICE1_OFFSET;
709 	ENVSIZE (0) = ENV1_SIZE;
710 	DEVESIZE (0) = DEVICE1_ESIZE;
711 #ifdef HAVE_REDUND
712 	strcpy (DEVNAME (1), DEVICE2_NAME);
713 	DEVOFFSET (1) = DEVICE2_OFFSET;
714 	ENVSIZE (1) = ENV2_SIZE;
715 	DEVESIZE (1) = DEVICE2_ESIZE;
716 	HaveRedundEnv = 1;
717 #endif
718 #endif
719 	if (stat (DEVNAME (0), &st)) {
720 		fprintf (stderr,
721 			"Cannot access MTD device %s: %s\n",
722 			DEVNAME (0), strerror (errno));
723 		return 1;
724 	}
725 
726 	if (HaveRedundEnv && stat (DEVNAME (1), &st)) {
727 		fprintf (stderr,
728 			"Cannot access MTD device %s: %s\n",
729 			DEVNAME (1), strerror (errno));
730 		return 1;
731 	}
732 	return 0;
733 }
734 
735 #if defined(CONFIG_FILE)
736 static int get_config (char *fname)
737 {
738 	FILE *fp;
739 	int i = 0;
740 	int rc;
741 	char dump[128];
742 
743 	if ((fp = fopen (fname, "r")) == NULL) {
744 		return 1;
745 	}
746 
747 	while ((i < 2) && ((rc = fscanf (fp, "%s %lx %lx %lx",
748 				  DEVNAME (i),
749 				  &DEVOFFSET (i),
750 				  &ENVSIZE (i),
751 				  &DEVESIZE (i)  )) != EOF)) {
752 
753 		/* Skip incomplete conversions and comment strings */
754 		if ((rc < 3) || (*DEVNAME (i) == '#')) {
755 			fgets (dump, sizeof (dump), fp);	/* Consume till end */
756 			continue;
757 		}
758 
759 		i++;
760 	}
761 	fclose (fp);
762 
763 	HaveRedundEnv = i - 1;
764 	if (!i) {			/* No valid entries found */
765 		errno = EINVAL;
766 		return 1;
767 	} else
768 		return 0;
769 }
770 #endif
771