Systemd/src/binfmt/binfmt.c
Zbigniew Jędrzejewski-Szmek 601185b43d Unify parse_argv style
getopt is usually good at printing out a nice error message when
commandline options are invalid. It distinguishes between an unknown
option and a known option with a missing arg. It is better to let it
do its job and not use opterr=0 unless we actually want to suppress
messages. So remove opterr=0 in the few places where it wasn't really
useful.

When an error in options is encountered, we should not print a lengthy
help() and overwhelm the user, when we know precisely what is wrong
with the commandline. In addition, since help() prints to stdout, it
should not be used except when requested with -h or --help.

Also, simplify things here and there.
2014-08-03 21:46:07 -04:00

219 lines
5.6 KiB
C

/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright 2010 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <stdlib.h>
#include <stdbool.h>
#include <errno.h>
#include <string.h>
#include <stdio.h>
#include <limits.h>
#include <stdarg.h>
#include <getopt.h>
#include "log.h"
#include "hashmap.h"
#include "strv.h"
#include "util.h"
#include "conf-files.h"
#include "fileio.h"
#include "build.h"
static const char conf_file_dirs[] =
"/etc/binfmt.d\0"
"/run/binfmt.d\0"
"/usr/local/lib/binfmt.d\0"
"/usr/lib/binfmt.d\0"
#ifdef HAVE_SPLIT_USR
"/lib/binfmt.d\0"
#endif
;
static int delete_rule(const char *rule) {
_cleanup_free_ char *x = NULL, *fn = NULL;
char *e;
assert(rule[0]);
x = strdup(rule);
if (!x)
return log_oom();
e = strchrnul(x+1, x[0]);
*e = 0;
fn = strappend("/proc/sys/fs/binfmt_misc/", x+1);
if (!fn)
return log_oom();
return write_string_file(fn, "-1");
}
static int apply_rule(const char *rule) {
int r;
delete_rule(rule);
r = write_string_file("/proc/sys/fs/binfmt_misc/register", rule);
if (r < 0) {
log_error("Failed to add binary format: %s", strerror(-r));
return r;
}
return 0;
}
static int apply_file(const char *path, bool ignore_enoent) {
_cleanup_fclose_ FILE *f = NULL;
int r;
assert(path);
r = search_and_fopen_nulstr(path, "re", NULL, conf_file_dirs, &f);
if (r < 0) {
if (ignore_enoent && r == -ENOENT)
return 0;
log_error("Failed to open file '%s', ignoring: %s", path, strerror(-r));
return r;
}
log_debug("apply: %s", path);
for (;;) {
char l[LINE_MAX], *p;
int k;
if (!fgets(l, sizeof(l), f)) {
if (feof(f))
break;
log_error("Failed to read file '%s', ignoring: %m", path);
return -errno;
}
p = strstrip(l);
if (!*p)
continue;
if (strchr(COMMENTS "\n", *p))
continue;
k = apply_rule(p);
if (k < 0 && r == 0)
r = k;
}
return r;
}
static void help(void) {
printf("%s [OPTIONS...] [CONFIGURATION FILE...]\n\n"
"Registers binary formats.\n\n"
" -h --help Show this help\n"
" --version Show package version\n"
, program_invocation_short_name);
}
static int parse_argv(int argc, char *argv[]) {
enum {
ARG_VERSION = 0x100,
};
static const struct option options[] = {
{ "help", no_argument, NULL, 'h' },
{ "version", no_argument, NULL, ARG_VERSION },
{}
};
int c;
assert(argc >= 0);
assert(argv);
while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0)
switch (c) {
case 'h':
help();
return 0;
case ARG_VERSION:
puts(PACKAGE_STRING);
puts(SYSTEMD_FEATURES);
return 0;
case '?':
return -EINVAL;
default:
assert_not_reached("Unhandled option");
}
return 1;
}
int main(int argc, char *argv[]) {
int r, k;
r = parse_argv(argc, argv);
if (r <= 0)
return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
log_set_target(LOG_TARGET_AUTO);
log_parse_environment();
log_open();
umask(0022);
r = 0;
if (argc > optind) {
int i;
for (i = optind; i < argc; i++) {
k = apply_file(argv[i], false);
if (k < 0 && r == 0)
r = k;
}
} else {
_cleanup_strv_free_ char **files = NULL;
char **f;
r = conf_files_list_nulstr(&files, ".conf", NULL, conf_file_dirs);
if (r < 0) {
log_error("Failed to enumerate binfmt.d files: %s", strerror(-r));
goto finish;
}
/* Flush out all rules */
write_string_file("/proc/sys/fs/binfmt_misc/status", "-1");
STRV_FOREACH(f, files) {
k = apply_file(*f, true);
if (k < 0 && r == 0)
r = k;
}
}
finish:
return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}