freebsd-dev/usr.sbin/nvram/nvram.c
Maxim Sobolev e5d34218fb Add device to access and modify Open Firmware NVRAM settings in
PowerPC-based Apple's machines and small utility to do it from
userland modelled after the similar utility in Darwin/OSX.

Only tested on 1.25GHz G4 Mac Mini.

MFC after:	1 month
2006-08-01 22:19:01 +00:00

223 lines
5.2 KiB
C

/*
* Copyright (c) 2006 Maxim Sobolev <sobomax@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* $FreeBSD$
*/
#include <sys/types.h>
#include <sys/uio.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <paths.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <dev/powermac_nvram/powermac_nvramvar.h>
#define DEVICE_NAME (_PATH_DEV "powermac_nvram")
static void usage(void);
static int remove_var(uint8_t *, int, const char *);
static int append_var(uint8_t *, int, const char *, const char *);
struct deletelist {
char *name;
struct deletelist *next;
struct deletelist *last;
};
int
main(int argc, char **argv)
{
int opt, dump, fd, res, i, size;
uint8_t buf[NVRAM_SIZE], *cp, *common;
struct chrp_header *header;
struct deletelist *dl;
dump = 0;
dl = NULL;
while((opt = getopt(argc, argv, "d:p")) != -1) {
switch(opt) {
case 'p':
dump = 1;
break;
case 'd':
if (dl == NULL) {
dl = malloc(sizeof(*dl));
if (dl == NULL)
err(1, "malloc");
bzero(dl, sizeof(*dl));
dl->last = dl;
} else {
dl->last->next = malloc(sizeof(*dl));
if (dl->last->next == NULL)
err(1, "malloc");
dl->last = dl->last->next;
bzero(dl->last, sizeof(*dl));
}
dl->last->name = optarg;
break;
default:
usage();
/* Not reached */
}
}
argc -= optind;
argv += optind;
if (argc == 0 && dump == 0 && dl == NULL) {
usage();
/* Not reached */
}
fd = open(DEVICE_NAME, O_RDWR);
if (fd == -1)
err(1, DEVICE_NAME);
for (i = 0; i < (int)sizeof(buf);) {
res = read(fd, buf + i, sizeof(buf) - i);
if (res == -1 && errno != EINTR)
err(1, DEVICE_NAME);
if (res == 0)
break;
if (res > 0)
i += res;
}
if (i != sizeof(buf))
errx(1, "%s: short read", DEVICE_NAME);
/* Locate common block */
size = 0;
for (cp = buf; cp < buf + sizeof(buf); cp += size) {
header = (struct chrp_header *)cp;
size = header->length * 0x10;
if (strncmp(header->name, "common", 7) == 0)
break;
}
if (cp >= buf + sizeof(buf) || size <= (int)sizeof(struct chrp_header))
errx(1, "%s: no common block", DEVICE_NAME);
common = cp + sizeof(struct chrp_header);
size -= sizeof(struct chrp_header);
if (dump != 0) {
while (size > 0) {
i = strlen(common) + 1;
if (i == 1)
break;
printf("%s\n", common);
size -= i;
common += i;
}
exit(0);
}
for (;dl != NULL; dl = dl->next) {
if (remove_var(common, size, dl->name) == 0)
warnx("%s: no such variable", dl->name);
}
for (; argc > 0; argc--, argv++) {
cp = strchr(*argv, '=');
if (cp == NULL)
errx(1, "%s: invalid argument", *argv);
cp[0] = '\0';
cp++;
remove_var(common, size, *argv);
if (append_var(common, size, *argv, cp) == -1)
errx(1, "%s: error setting variable", *argv);
}
for (i = 0; i < (int)sizeof(buf);) {
res = write(fd, buf + i, sizeof(buf) - i);
if (res == -1 && errno != EINTR)
err(1, DEVICE_NAME);
if (res == 0)
break;
if (res > 0)
i += res;
}
if (i != sizeof(buf))
errx(1, "%s: short write", DEVICE_NAME);
if (close(fd) == -1)
err(1, DEVICE_NAME);
exit(0);
}
static void
usage(void)
{
fprintf(stderr, "usage: nvram [-p] | [-d name ...] [name=value ...]\n");
exit(1);
}
static int
remove_var(uint8_t *buf, int len, const char *var_name)
{
int nremoved, i, name_len;
nremoved = 0;
name_len = strlen(var_name);
while (len > 0) {
i = strlen(buf) + 1;
if (i == 1)
break;
if (strncmp(buf, var_name, name_len) == 0 && buf[name_len] == '=') {
memmove(buf, buf + i, len - i);
memset(buf + len - i, '\0', i);
nremoved += 1;
continue;
}
len -= i;
buf += i;
}
return nremoved;
}
static int
append_var(uint8_t *buf, int len, const char *var_name, const char *var_value)
{
int i, append_len;
while (len > 0) {
i = strlen(buf) + 1;
if (i == 1)
break;
len -= i;
buf += i;
}
append_len = strlen(var_name) + strlen(var_value) + 2;
if (len < append_len)
return -1;
sprintf(buf, "%s=%s", var_name, var_value);
return 0;
}