diff options
Diffstat (limited to 'src/basic/proc-cmdline.c')
| -rw-r--r-- | src/basic/proc-cmdline.c | 133 |
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[] = { |