-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
-/***
- This file is part of systemd.
-
- Copyright 2012 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/>.
-***/
+/* SPDX-License-Identifier: LGPL-2.1+ */
#include <errno.h>
#include <unistd.h>
+#include "fs-util.h"
+#include "generator.h"
#include "log.h"
+#include "proc-cmdline.h"
+#include "special.h"
+#include "string-util.h"
#include "util.h"
-#include "unit-name.h"
-#include "path-util.h"
-static const char *arg_dest = "/tmp";
+/*
+ * Implements the logic described in systemd.offline-updates(7).
+ */
+
+static const char *arg_dest = NULL;
static int generate_symlink(void) {
- struct stat st;
- char *p;
+ const char *p = NULL;
- if (lstat("/system-update", &st) < 0) {
+ if (laccess("/system-update", F_OK) < 0) {
if (errno == ENOENT)
return 0;
- log_error("Failed to check for system update: %m");
+ log_error_errno(errno, "Failed to check for system update: %m");
return -EINVAL;
}
- p = strappend(arg_dest, "/default.target");
- if (!p) {
- log_error("Out of memory.");
- return -ENOMEM;
- }
+ p = strjoina(arg_dest, "/" SPECIAL_DEFAULT_TARGET);
+ if (symlink(SYSTEM_DATA_UNIT_PATH "/system-update.target", p) < 0)
+ return log_error_errno(errno, "Failed to create symlink %s: %m", p);
- if (symlink(SYSTEM_DATA_UNIT_PATH "/system-update.target", p) < 0) {
- free(p);
- log_error("Failed to create symlink: %m");
- return -errno;
- }
+ return 1;
+}
- free(p);
+static int parse_proc_cmdline_item(const char *key, const char *value, void *data) {
+ assert(key);
+
+ /* Check if a run level is specified on the kernel command line. The
+ * command line has higher priority than any on-disk configuration, so
+ * it'll make any symlink we create moot.
+ */
+
+ if (streq(key, "systemd.unit") && !proc_cmdline_value_missing(key, value))
+ log_warning("Offline system update overridden by kernel command line systemd.unit= setting");
+ else if (!value && runlevel_to_target(key))
+ log_warning("Offline system update overridden by runlevel \"%s\" on the kernel command line", key);
return 0;
}
-int main(int argc, char *argv[]) {
+static int run(const char *dest, const char *dest_early, const char *dest_late) {
int r;
- if (argc > 2) {
- log_error("This program takes one or no arguments.");
- return EXIT_FAILURE;
- }
-
- if (argc > 1)
- arg_dest = argv[1];
-
- log_set_target(LOG_TARGET_AUTO);
- log_parse_environment();
- log_open();
-
- umask(0022);
+ assert_se(arg_dest = dest_early);
r = generate_symlink();
+ if (r < 0)
+ return r;
+
+ r = proc_cmdline_parse(parse_proc_cmdline_item, NULL, 0);
+ if (r < 0)
+ log_warning_errno(r, "Failed to parse kernel command line, ignoring: %m");
- return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
+ return 0;
}
+
+DEFINE_MAIN_GENERATOR_FUNCTION(run);