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Diffstat (limited to 'src/basic/proc-cmdline.c')
-rw-r--r--src/basic/proc-cmdline.c133
1 files changed, 108 insertions, 25 deletions
diff --git a/src/basic/proc-cmdline.c b/src/basic/proc-cmdline.c
index 98c94ed5e2..6ecb6c3f0d 100644
--- a/src/basic/proc-cmdline.c
+++ b/src/basic/proc-cmdline.c
@@ -56,9 +56,8 @@ int proc_cmdline(char **ret) {
return read_one_line_file("/proc/cmdline", ret);
}
-int parse_proc_cmdline(int (*parse_item)(const char *key, const char *value, void *data),
- void *data,
- bool strip_prefix) {
+int proc_cmdline_parse(proc_cmdline_parse_t parse_item, void *data, unsigned flags) {
+
_cleanup_free_ char *line = NULL;
const char *p;
int r;
@@ -72,7 +71,7 @@ int parse_proc_cmdline(int (*parse_item)(const char *key, const char *value, voi
p = line;
for (;;) {
_cleanup_free_ char *word = NULL;
- char *value = NULL, *unprefixed;
+ char *value, *key, *q;
r = extract_first_word(&p, &word, NULL, EXTRACT_QUOTES|EXTRACT_RELAX);
if (r < 0)
@@ -80,17 +79,23 @@ int parse_proc_cmdline(int (*parse_item)(const char *key, const char *value, voi
if (r == 0)
break;
- /* Filter out arguments that are intended only for the
- * initrd */
- unprefixed = startswith(word, "rd.");
- if (unprefixed && !in_initrd())
- continue;
+ 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(word, '=');
+ value = strchr(key, '=');
if (value)
*(value++) = 0;
- r = parse_item(strip_prefix && unprefixed ? unprefixed : word, value, data);
+ r = parse_item(key, value, data);
if (r < 0)
return r;
}
@@ -98,13 +103,64 @@ int parse_proc_cmdline(int (*parse_item)(const char *key, const char *value, voi
return 0;
}
-int get_proc_cmdline_key(const char *key, char **value) {
+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;
- assert(key);
+ /* 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)
@@ -121,21 +177,26 @@ int get_proc_cmdline_key(const char *key, char **value) {
if (r == 0)
break;
- /* Filter out arguments that are intended only for the
- * initrd */
+ /* 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 = startswith(word, key);
+ e = proc_cmdline_key_startswith(word, key);
if (!e)
continue;
- r = free_and_strdup(&ret, e);
- if (r < 0)
- return r;
+ 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;
- found = true;
} else {
if (streq(word, key))
found = true;
@@ -148,20 +209,42 @@ int get_proc_cmdline_key(const char *key, char **value) {
}
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) {
- _cleanup_free_ char *value = NULL;
+ bool ret;
int r;
- r = get_proc_cmdline_key("systemd.restore_state=", &value);
+ r = proc_cmdline_get_bool("systemd.restore_state", &ret);
if (r < 0)
return r;
- if (r == 0)
- return true;
- return parse_boolean(value);
+ return r > 0 ? ret : true;
}
static const char * const rlmap[] = {