/***
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 <stdbool.h>
#include <stddef.h>
#include <string.h>
#include "alloc-util.h"
#include "extract-word.h"
#include "fileio.h"
#include "macro.h"
#include "parse-util.h"
#include "proc-cmdline.h"
#include "process-util.h"
#include "special.h"
#include "string-util.h"
#include "util.h"
#include "virt.h"
int proc_cmdline(char **ret) {
const char *e;
assert(ret);
/* For testing purposes it is sometimes useful to be able to override what we consider /proc/cmdline to be */
e = secure_getenv("SYSTEMD_PROC_CMDLINE");
if (e) {
char *m;
m = strdup(e);
if (!m)
return -ENOMEM;
*ret = m;
return 0;
}
if (detect_container() > 0)
return get_process_cmdline(1, 0, false, ret);
else
return read_one_line_file("/proc/cmdline", ret);
}
int proc_cmdline_parse(proc_cmdline_parse_t parse_item, void *data, unsigned flags) {
_cleanup_free_ char *line = NULL;
const char *p;
int r;
assert(parse_item);
r = proc_cmdline(&line);
if (r < 0)
return r;
p = line;
for (;;) {
_cleanup_free_ char *word = NULL;
char *value, *key, *q;
r = extract_first_word(&p, &word, NULL, EXTRACT_QUOTES|EXTRACT_RELAX);
if (r < 0)
return r;
if (r == 0)
break;
key = word;
/* Filter out arguments that are intended only for the initrd */
q = startswith(word, "rd.");
if (q) {
if (!in_initrd())
continue;
if (flags & PROC_CMDLINE_STRIP_RD_PREFIX)
key = q;
}
value = strchr(key, '=');
if (value)
*(value++) = 0;
r = parse_item(key, value, data);
if (r < 0)
return r;
}
return 0;
}
static bool relaxed_equal_char(char a, char b) {
return a == b ||
(a == '_' && b == '-') ||
(a == '-' && b == '_');
}
char *proc_cmdline_key_startswith(const char *s, const char *prefix) {
assert(s);
assert(prefix);
/* Much like startswith(), but considers "-" and "_" the same */
for (; *prefix != 0; s++, prefix++)
if (!relaxed_equal_char(*s, *prefix))
return NULL;
return (char*) s;
}
bool proc_cmdline_key_streq(const char *x, const char *y) {
assert(x);
assert(y);
/* Much like streq(), but considers "-" and "_" the same */
for (; *x != 0 || *y != 0; x++, y++)
if (!relaxed_equal_char(*x, *y))
return false;
return true;
}
int proc_cmdline_get_key(const char *key, unsigned flags, char **value) {
_cleanup_free_ char *line = NULL, *ret = NULL;
bool found = false;
const char *p;
int r;
/* Looks for a specific key on the kernel command line. Supports two modes:
*
* a) The "value" parameter is used. In this case a parameter beginning with the "key" string followed by "="
* is searched, and the value following this is returned in "value".
*
* b) as above, but the PROC_CMDLINE_VALUE_OPTIONAL flag is set. In this case if the the key is found as a
* separate word (i.e. not followed by "=" but instead by whitespace or the end of the command line), then
* this is also accepted, and "value" is returned as NULL.
*
* c) The "value" parameter is NULL. In this case a search for the exact "key" parameter is performed.
*
* In all three cases, > 0 is returned if the key is found, 0 if not.*/
if (isempty(key))
return -EINVAL;
if ((flags & PROC_CMDLINE_VALUE_OPTIONAL) && !value)
return -EINVAL;
r = proc_cmdline(&line);
if (r < 0)
return r;
p = line;
for (;;) {
_cleanup_free_ char *word = NULL;
const char *e;
r = extract_first_word(&p, &word, NULL, EXTRACT_QUOTES|EXTRACT_RELAX);
if (r < 0)
return r;
if (r == 0)
break;
/* Automatically filter out arguments that are intended only for the initrd, if we are not in the
* initrd. */
if (!in_initrd() && startswith(word, "rd."))
continue;
if (value) {
e = proc_cmdline_key_startswith(word, key);
if (!e)
continue;
if (*e == '=') {
r = free_and_strdup(&ret, e+1);
if (r < 0)
return r;
found = true;
} else if (*e == 0 && (flags & PROC_CMDLINE_VALUE_OPTIONAL))
found = true;
} else {
if (streq(word, key))
found = true;
}
}
if (value) {
*value = ret;
ret = NULL;
}
return found;
}
int proc_cmdline_get_bool(const char *key, bool *ret) {
_cleanup_free_ char *v = NULL;
int r;
assert(ret);
r = proc_cmdline_get_key(key, PROC_CMDLINE_VALUE_OPTIONAL, &v);
if (r < 0)
return r;
if (r == 0) {
*ret = false;
return 0;
}
if (v) { /* parameter passed */
r = parse_boolean(v);
if (r < 0)
return r;
*ret = r;
} else /* no parameter passed */
*ret = true;
return 1;
}
int shall_restore_state(void) {
bool ret;
int r;
r = proc_cmdline_get_bool("systemd.restore_state", &ret);
if (r < 0)
return r;
return r > 0 ? ret : true;
}
static const char * const rlmap[] = {
"emergency", SPECIAL_EMERGENCY_TARGET,
"-b", SPECIAL_EMERGENCY_TARGET,
"rescue", SPECIAL_RESCUE_TARGET,
"single", SPECIAL_RESCUE_TARGET,
"-s", SPECIAL_RESCUE_TARGET,
"s", SPECIAL_RESCUE_TARGET,
"S", SPECIAL_RESCUE_TARGET,
"1", SPECIAL_RESCUE_TARGET,
"2", SPECIAL_MULTI_USER_TARGET,
"3", SPECIAL_MULTI_USER_TARGET,
"4", SPECIAL_MULTI_USER_TARGET,
"5", SPECIAL_GRAPHICAL_TARGET,
NULL
};
static const char * const rlmap_initrd[] = {
"emergency", SPECIAL_EMERGENCY_TARGET,
"rescue", SPECIAL_RESCUE_TARGET,
NULL
};
const char* runlevel_to_target(const char *word) {
size_t i;
const char * const *rlmap_ptr = in_initrd() ? rlmap_initrd
: rlmap;
if (!word)
return NULL;
if (in_initrd() && (word = startswith(word, "rd.")) == NULL)
return NULL;
for (i = 0; rlmap_ptr[i] != NULL; i += 2)
if (streq(word, rlmap_ptr[i]))
return rlmap_ptr[i+1];
return NULL;
}