1 /* SPDX-License-Identifier: LGPL-2.1+ */
3 This file is part of systemd.
5 Copyright 2010 Lennart Poettering
7 systemd is free software; you can redistribute it and/or modify it
8 under the terms of the GNU Lesser General Public License as published by
9 the Free Software Foundation; either version 2.1 of the License, or
10 (at your option) any later version.
12 systemd is distributed in the hope that it will be useful, but
13 WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 Lesser General Public License for more details.
17 You should have received a copy of the GNU Lesser General Public License
18 along with systemd; If not, see <http://www.gnu.org/licenses/>.
25 #include "alloc-util.h"
26 #include "extract-word.h"
29 #include "parse-util.h"
30 #include "proc-cmdline.h"
31 #include "process-util.h"
32 //#include "special.h"
33 #include "string-util.h"
37 int proc_cmdline(char **ret) {
41 /* For testing purposes it is sometimes useful to be able to override what we consider /proc/cmdline to be */
42 e = secure_getenv("SYSTEMD_PROC_CMDLINE");
54 if (detect_container() > 0)
55 return get_process_cmdline(1, 0, false, ret);
57 return read_one_line_file("/proc/cmdline", ret);
60 int proc_cmdline_parse(proc_cmdline_parse_t parse_item, void *data, unsigned flags) {
62 _cleanup_free_ char *line = NULL;
68 r = proc_cmdline(&line);
74 _cleanup_free_ char *word = NULL;
75 char *value, *key, *q;
77 r = extract_first_word(&p, &word, NULL, EXTRACT_QUOTES|EXTRACT_RELAX);
85 /* Filter out arguments that are intended only for the initrd */
86 q = startswith(word, "rd.");
91 if (flags & PROC_CMDLINE_STRIP_RD_PREFIX)
95 value = strchr(key, '=');
99 r = parse_item(key, value, data);
107 static bool relaxed_equal_char(char a, char b) {
110 (a == '_' && b == '-') ||
111 (a == '-' && b == '_');
114 #if 0 /// UNNEEDED by elogind
115 char *proc_cmdline_key_startswith(const char *s, const char *prefix) {
120 /* Much like startswith(), but considers "-" and "_" the same */
122 for (; *prefix != 0; s++, prefix++)
123 if (!relaxed_equal_char(*s, *prefix))
130 bool proc_cmdline_key_streq(const char *x, const char *y) {
134 /* Much like streq(), but considers "-" and "_" the same */
136 for (; *x != 0 || *y != 0; x++, y++)
137 if (!relaxed_equal_char(*x, *y))
143 #if 0 /// UNNEEDED by elogind
144 int proc_cmdline_get_key(const char *key, unsigned flags, char **value) {
145 _cleanup_free_ char *line = NULL, *ret = NULL;
150 /* Looks for a specific key on the kernel command line. Supports two modes:
152 * a) The "value" parameter is used. In this case a parameter beginning with the "key" string followed by "="
153 * is searched, and the value following this is returned in "value".
155 * b) as above, but the PROC_CMDLINE_VALUE_OPTIONAL flag is set. In this case if the key is found as a
156 * separate word (i.e. not followed by "=" but instead by whitespace or the end of the command line), then
157 * this is also accepted, and "value" is returned as NULL.
159 * c) The "value" parameter is NULL. In this case a search for the exact "key" parameter is performed.
161 * In all three cases, > 0 is returned if the key is found, 0 if not. */
166 if ((flags & PROC_CMDLINE_VALUE_OPTIONAL) && !value)
169 r = proc_cmdline(&line);
175 _cleanup_free_ char *word = NULL;
178 r = extract_first_word(&p, &word, NULL, EXTRACT_QUOTES|EXTRACT_RELAX);
184 /* Automatically filter out arguments that are intended only for the initrd, if we are not in the
186 if (!in_initrd() && startswith(word, "rd."))
190 e = proc_cmdline_key_startswith(word, key);
195 r = free_and_strdup(&ret, e+1);
201 } else if (*e == 0 && (flags & PROC_CMDLINE_VALUE_OPTIONAL))
205 if (streq(word, key))
211 *value = TAKE_PTR(ret);
216 int proc_cmdline_get_bool(const char *key, bool *ret) {
217 _cleanup_free_ char *v = NULL;
222 r = proc_cmdline_get_key(key, PROC_CMDLINE_VALUE_OPTIONAL, &v);
230 if (v) { /* parameter passed */
231 r = parse_boolean(v);
235 } else /* no parameter passed */
241 int shall_restore_state(void) {
245 r = proc_cmdline_get_bool("systemd.restore_state", &ret);
249 return r > 0 ? ret : true;
252 static const char * const rlmap[] = {
253 "emergency", SPECIAL_EMERGENCY_TARGET,
254 "-b", SPECIAL_EMERGENCY_TARGET,
255 "rescue", SPECIAL_RESCUE_TARGET,
256 "single", SPECIAL_RESCUE_TARGET,
257 "-s", SPECIAL_RESCUE_TARGET,
258 "s", SPECIAL_RESCUE_TARGET,
259 "S", SPECIAL_RESCUE_TARGET,
260 "1", SPECIAL_RESCUE_TARGET,
261 "2", SPECIAL_MULTI_USER_TARGET,
262 "3", SPECIAL_MULTI_USER_TARGET,
263 "4", SPECIAL_MULTI_USER_TARGET,
264 "5", SPECIAL_GRAPHICAL_TARGET,
268 static const char * const rlmap_initrd[] = {
269 "emergency", SPECIAL_EMERGENCY_TARGET,
270 "rescue", SPECIAL_RESCUE_TARGET,
274 const char* runlevel_to_target(const char *word) {
275 const char * const *rlmap_ptr;
282 word = startswith(word, "rd.");
287 rlmap_ptr = in_initrd() ? rlmap_initrd : rlmap;
289 for (i = 0; rlmap_ptr[i]; i += 2)
290 if (streq(word, rlmap_ptr[i]))
291 return rlmap_ptr[i+1];