barebox/scripts/bareboxenv.c
Juergen Borleis e805b7dcb0 saveenv: provide a zeroed/empty/ignore environment
If an external environment storage should be used in very rare and special cases,
the intentional behaviour should be to ignore the external environment and always
fall back to the built-in environment. By storing an empty "to be ignored" environment
into the external environment a confusing error message about invalid CRC sums will go
away and still the built-in environment is used.
With this new option we can force the intentional behaviour.

Signed-off-by: Juergen Borleis <jbe@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
2014-08-01 08:24:00 +02:00

197 lines
4.5 KiB
C

/*
* bareboxenv.c - generate or read a barebox environment archive
*
* Copyright (c) 2007 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
*/
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdint.h>
#include <limits.h>
#include <errno.h>
#include <dirent.h>
#include <stdlib.h>
#include <string.h>
#include <getopt.h>
#include <libgen.h>
#include "compiler.h"
#define debug(...)
/* Find out if the last character of a string matches the one given.
* Don't underrun the buffer if the string length is 0.
*/
static char *last_char_is(const char *s, int c)
{
if (s && *s) {
size_t sz = strlen(s) - 1;
s += sz;
if ( (unsigned char)*s == c)
return (char*)s;
}
return NULL;
}
enum {
ACTION_RECURSE = (1 << 0),
ACTION_FOLLOWLINKS = (1 << 1),
ACTION_DEPTHFIRST = (1 << 2),
/*ACTION_REVERSE = (1 << 3), - unused */
};
int recursive_action(const char *fileName, unsigned flags,
int (*fileAction) (const char *fileName, struct stat* statbuf, void* userData, int depth),
int (*dirAction) (const char *fileName, struct stat* statbuf, void* userData, int depth),
void* userData, const unsigned depth);
#define DOT_OR_DOTDOT(s) ((s)[0] == '.' && (!(s)[1] || ((s)[1] == '.' && !(s)[2])))
/* concatenate path and file name to new allocation buffer,
* not adding '/' if path name already has '/'
*/
static char *concat_path_file(const char *path, const char *filename)
{
char *lc, *str;
if (!path)
path = "";
lc = last_char_is(path, '/');
while (*filename == '/')
filename++;
str = xmalloc(strlen(path) + (lc==0 ? 1 : 0) + strlen(filename) + 1);
sprintf(str, "%s%s%s", path, (lc==NULL ? "/" : ""), filename);
return str;
}
/*
* This function make special for recursive actions with usage
* concat_path_file(path, filename)
* and skipping "." and ".." directory entries
*/
static char *concat_subpath_file(const char *path, const char *f)
{
if (f && DOT_OR_DOTDOT(f))
return NULL;
return concat_path_file(path, f);
}
#include "../lib/recursive_action.c"
#include "../include/envfs.h"
#include "../crypto/crc32.c"
#include "../lib/make_directory.c"
#include "../common/environment.c"
static void usage(char *prgname)
{
printf( "Usage : %s [OPTION] DIRECTORY FILE\n"
"Load a barebox environment sector into a directory or\n"
"save a directory into a barebox environment sector\n"
"\n"
"options:\n"
" -s save (directory -> environment sector)\n"
" -z force the built-in default environment at startup\n"
" -l load (environment sector -> directory)\n"
" -p <size> pad output file to given size\n"
" -v verbose\n",
prgname);
}
int main(int argc, char *argv[])
{
int opt;
int save = 0, load = 0, pad = 0, err = 0, fd;
char *filename = NULL, *dirname = NULL;
unsigned envfs_flags = 0;
int verbose = 0;
while((opt = getopt(argc, argv, "slp:vz")) != -1) {
switch (opt) {
case 's':
save = 1;
break;
case 'l':
load = 1;
break;
case 'p':
pad = strtoul(optarg, NULL, 0);
break;
case 'z':
envfs_flags |= ENVFS_FLAGS_FORCE_BUILT_IN;
save = 1;
break;
case 'v':
verbose = 1;
break;
}
}
if (optind + 1 >= argc) {
usage(argv[0]);
exit(1);
}
dirname = argv[optind];
filename = argv[optind + 1];
if ((!load && !save) || (load && save) || !filename || !dirname) {
usage(argv[0]);
exit(1);
}
if (save) {
fd = open(filename, O_CREAT | O_TRUNC | O_WRONLY, 0644);
if (fd < 0) {
perror("open");
exit(1);
}
close(fd);
}
if (save && pad) {
if (truncate(filename, pad)) {
perror("truncate");
exit(1);
}
}
if (load) {
if (verbose)
printf("loading env from file %s to %s\n", filename, dirname);
err = envfs_load(filename, dirname, 0);
if (verbose && err)
printf("loading env failed: %d\n", err);
}
if (save) {
if (verbose)
printf("saving contents of %s to file %s\n", dirname, filename);
err = envfs_save(filename, dirname, envfs_flags);
if (verbose && err)
printf("saving env failed: %d\n", err);
}
exit(err ? 1 : 0);
}