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-rw-r--r--src/libsystemd-shared/src/conf-parser.c961
1 files changed, 961 insertions, 0 deletions
diff --git a/src/libsystemd-shared/src/conf-parser.c b/src/libsystemd-shared/src/conf-parser.c
new file mode 100644
index 0000000000..81c40a8891
--- /dev/null
+++ b/src/libsystemd-shared/src/conf-parser.c
@@ -0,0 +1,961 @@
+/***
+ 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 <errno.h>
+#include <limits.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+
+#include "systemd-basic/alloc-util.h"
+#include "systemd-basic/conf-files.h"
+#include "systemd-basic/extract-word.h"
+#include "systemd-basic/fd-util.h"
+#include "systemd-basic/fs-util.h"
+#include "systemd-basic/log.h"
+#include "systemd-basic/macro.h"
+#include "systemd-basic/parse-util.h"
+#include "systemd-basic/path-util.h"
+#include "systemd-basic/process-util.h"
+#include "systemd-basic/signal-util.h"
+#include "systemd-basic/socket-util.h"
+#include "systemd-basic/string-util.h"
+#include "systemd-basic/strv.h"
+#include "systemd-basic/syslog-util.h"
+#include "systemd-basic/time-util.h"
+#include "systemd-basic/utf8.h"
+#include "systemd-shared/conf-parser.h"
+
+int config_item_table_lookup(
+ const void *table,
+ const char *section,
+ const char *lvalue,
+ ConfigParserCallback *func,
+ int *ltype,
+ void **data,
+ void *userdata) {
+
+ const ConfigTableItem *t;
+
+ assert(table);
+ assert(lvalue);
+ assert(func);
+ assert(ltype);
+ assert(data);
+
+ for (t = table; t->lvalue; t++) {
+
+ if (!streq(lvalue, t->lvalue))
+ continue;
+
+ if (!streq_ptr(section, t->section))
+ continue;
+
+ *func = t->parse;
+ *ltype = t->ltype;
+ *data = t->data;
+ return 1;
+ }
+
+ return 0;
+}
+
+int config_item_perf_lookup(
+ const void *table,
+ const char *section,
+ const char *lvalue,
+ ConfigParserCallback *func,
+ int *ltype,
+ void **data,
+ void *userdata) {
+
+ ConfigPerfItemLookup lookup = (ConfigPerfItemLookup) table;
+ const ConfigPerfItem *p;
+
+ assert(table);
+ assert(lvalue);
+ assert(func);
+ assert(ltype);
+ assert(data);
+
+ if (!section)
+ p = lookup(lvalue, strlen(lvalue));
+ else {
+ char *key;
+
+ key = strjoin(section, ".", lvalue, NULL);
+ if (!key)
+ return -ENOMEM;
+
+ p = lookup(key, strlen(key));
+ free(key);
+ }
+
+ if (!p)
+ return 0;
+
+ *func = p->parse;
+ *ltype = p->ltype;
+ *data = (uint8_t*) userdata + p->offset;
+ return 1;
+}
+
+/* Run the user supplied parser for an assignment */
+static int next_assignment(const char *unit,
+ const char *filename,
+ unsigned line,
+ ConfigItemLookup lookup,
+ const void *table,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ const char *rvalue,
+ bool relaxed,
+ void *userdata) {
+
+ ConfigParserCallback func = NULL;
+ int ltype = 0;
+ void *data = NULL;
+ int r;
+
+ assert(filename);
+ assert(line > 0);
+ assert(lookup);
+ assert(lvalue);
+ assert(rvalue);
+
+ r = lookup(table, section, lvalue, &func, &ltype, &data, userdata);
+ if (r < 0)
+ return r;
+
+ if (r > 0) {
+ if (func)
+ return func(unit, filename, line, section, section_line,
+ lvalue, ltype, rvalue, data, userdata);
+
+ return 0;
+ }
+
+ /* Warn about unknown non-extension fields. */
+ if (!relaxed && !startswith(lvalue, "X-"))
+ log_syntax(unit, LOG_WARNING, filename, line, 0, "Unknown lvalue '%s' in section '%s'", lvalue, section);
+
+ return 0;
+}
+
+/* Parse a variable assignment line */
+static int parse_line(const char* unit,
+ const char *filename,
+ unsigned line,
+ const char *sections,
+ ConfigItemLookup lookup,
+ const void *table,
+ bool relaxed,
+ bool allow_include,
+ char **section,
+ unsigned *section_line,
+ bool *section_ignored,
+ char *l,
+ void *userdata) {
+
+ char *e;
+
+ assert(filename);
+ assert(line > 0);
+ assert(lookup);
+ assert(l);
+
+ l = strstrip(l);
+
+ if (!*l)
+ return 0;
+
+ if (strchr(COMMENTS "\n", *l))
+ return 0;
+
+ if (startswith(l, ".include ")) {
+ _cleanup_free_ char *fn = NULL;
+
+ /* .includes are a bad idea, we only support them here
+ * for historical reasons. They create cyclic include
+ * problems and make it difficult to detect
+ * configuration file changes with an easy
+ * stat(). Better approaches, such as .d/ drop-in
+ * snippets exist.
+ *
+ * Support for them should be eventually removed. */
+
+ if (!allow_include) {
+ log_syntax(unit, LOG_ERR, filename, line, 0, ".include not allowed here. Ignoring.");
+ return 0;
+ }
+
+ fn = file_in_same_dir(filename, strstrip(l+9));
+ if (!fn)
+ return -ENOMEM;
+
+ return config_parse(unit, fn, NULL, sections, lookup, table, relaxed, false, false, userdata);
+ }
+
+ if (*l == '[') {
+ size_t k;
+ char *n;
+
+ k = strlen(l);
+ assert(k > 0);
+
+ if (l[k-1] != ']') {
+ log_syntax(unit, LOG_ERR, filename, line, 0, "Invalid section header '%s'", l);
+ return -EBADMSG;
+ }
+
+ n = strndup(l+1, k-2);
+ if (!n)
+ return -ENOMEM;
+
+ if (sections && !nulstr_contains(sections, n)) {
+
+ if (!relaxed && !startswith(n, "X-"))
+ log_syntax(unit, LOG_WARNING, filename, line, 0, "Unknown section '%s'. Ignoring.", n);
+
+ free(n);
+ *section = mfree(*section);
+ *section_line = 0;
+ *section_ignored = true;
+ } else {
+ free(*section);
+ *section = n;
+ *section_line = line;
+ *section_ignored = false;
+ }
+
+ return 0;
+ }
+
+ if (sections && !*section) {
+
+ if (!relaxed && !*section_ignored)
+ log_syntax(unit, LOG_WARNING, filename, line, 0, "Assignment outside of section. Ignoring.");
+
+ return 0;
+ }
+
+ e = strchr(l, '=');
+ if (!e) {
+ log_syntax(unit, LOG_WARNING, filename, line, 0, "Missing '='.");
+ return -EINVAL;
+ }
+
+ *e = 0;
+ e++;
+
+ return next_assignment(unit,
+ filename,
+ line,
+ lookup,
+ table,
+ *section,
+ *section_line,
+ strstrip(l),
+ strstrip(e),
+ relaxed,
+ userdata);
+}
+
+/* Go through the file and parse each line */
+int config_parse(const char *unit,
+ const char *filename,
+ FILE *f,
+ const char *sections,
+ ConfigItemLookup lookup,
+ const void *table,
+ bool relaxed,
+ bool allow_include,
+ bool warn,
+ void *userdata) {
+
+ _cleanup_free_ char *section = NULL, *continuation = NULL;
+ _cleanup_fclose_ FILE *ours = NULL;
+ unsigned line = 0, section_line = 0;
+ bool section_ignored = false, allow_bom = true;
+ int r;
+
+ assert(filename);
+ assert(lookup);
+
+ if (!f) {
+ f = ours = fopen(filename, "re");
+ if (!f) {
+ /* Only log on request, except for ENOENT,
+ * since we return 0 to the caller. */
+ if (warn || errno == ENOENT)
+ log_full(errno == ENOENT ? LOG_DEBUG : LOG_ERR,
+ "Failed to open configuration file '%s': %m", filename);
+ return errno == ENOENT ? 0 : -errno;
+ }
+ }
+
+ fd_warn_permissions(filename, fileno(f));
+
+ for (;;) {
+ char buf[LINE_MAX], *l, *p, *c = NULL, *e;
+ bool escaped = false;
+
+ if (!fgets(buf, sizeof buf, f)) {
+ if (feof(f))
+ break;
+
+ return log_error_errno(errno, "Failed to read configuration file '%s': %m", filename);
+ }
+
+ l = buf;
+ if (allow_bom && startswith(l, UTF8_BYTE_ORDER_MARK))
+ l += strlen(UTF8_BYTE_ORDER_MARK);
+ allow_bom = false;
+
+ truncate_nl(l);
+
+ if (continuation) {
+ c = strappend(continuation, l);
+ if (!c) {
+ if (warn)
+ log_oom();
+ return -ENOMEM;
+ }
+
+ continuation = mfree(continuation);
+ p = c;
+ } else
+ p = l;
+
+ for (e = p; *e; e++) {
+ if (escaped)
+ escaped = false;
+ else if (*e == '\\')
+ escaped = true;
+ }
+
+ if (escaped) {
+ *(e-1) = ' ';
+
+ if (c)
+ continuation = c;
+ else {
+ continuation = strdup(l);
+ if (!continuation) {
+ if (warn)
+ log_oom();
+ return -ENOMEM;
+ }
+ }
+
+ continue;
+ }
+
+ r = parse_line(unit,
+ filename,
+ ++line,
+ sections,
+ lookup,
+ table,
+ relaxed,
+ allow_include,
+ &section,
+ &section_line,
+ &section_ignored,
+ p,
+ userdata);
+ free(c);
+
+ if (r < 0) {
+ if (warn)
+ log_warning_errno(r, "Failed to parse file '%s': %m",
+ filename);
+ return r;
+ }
+ }
+
+ return 0;
+}
+
+static int config_parse_many_files(
+ const char *conf_file,
+ char **files,
+ const char *sections,
+ ConfigItemLookup lookup,
+ const void *table,
+ bool relaxed,
+ void *userdata) {
+
+ char **fn;
+ int r;
+
+ if (conf_file) {
+ r = config_parse(NULL, conf_file, NULL, sections, lookup, table, relaxed, false, true, userdata);
+ if (r < 0)
+ return r;
+ }
+
+ STRV_FOREACH(fn, files) {
+ r = config_parse(NULL, *fn, NULL, sections, lookup, table, relaxed, false, true, userdata);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+}
+
+/* Parse each config file in the directories specified as nulstr. */
+int config_parse_many_nulstr(
+ const char *conf_file,
+ const char *conf_file_dirs,
+ const char *sections,
+ ConfigItemLookup lookup,
+ const void *table,
+ bool relaxed,
+ void *userdata) {
+
+ _cleanup_strv_free_ char **files = NULL;
+ int r;
+
+ r = conf_files_list_nulstr(&files, ".conf", NULL, conf_file_dirs);
+ if (r < 0)
+ return r;
+
+ return config_parse_many_files(conf_file, files,
+ sections, lookup, table, relaxed, userdata);
+}
+
+/* Parse each config file in the directories specified as strv. */
+int config_parse_many(
+ const char *conf_file,
+ const char* const* conf_file_dirs,
+ const char *dropin_dirname,
+ const char *sections,
+ ConfigItemLookup lookup,
+ const void *table,
+ bool relaxed,
+ void *userdata) {
+
+ _cleanup_strv_free_ char **dropin_dirs = NULL;
+ _cleanup_strv_free_ char **files = NULL;
+ const char *suffix;
+ int r;
+
+ suffix = strjoina("/", dropin_dirname);
+ r = strv_extend_strv_concat(&dropin_dirs, (char**) conf_file_dirs, suffix);
+ if (r < 0)
+ return r;
+
+ r = conf_files_list_strv(&files, ".conf", NULL, (const char* const*) dropin_dirs);
+ if (r < 0)
+ return r;
+
+ return config_parse_many_files(conf_file, files,
+ sections, lookup, table, relaxed, userdata);
+}
+
+#define DEFINE_PARSER(type, vartype, conv_func) \
+ int config_parse_##type( \
+ const char *unit, \
+ const char *filename, \
+ unsigned line, \
+ const char *section, \
+ unsigned section_line, \
+ const char *lvalue, \
+ int ltype, \
+ const char *rvalue, \
+ void *data, \
+ void *userdata) { \
+ \
+ vartype *i = data; \
+ int r; \
+ \
+ assert(filename); \
+ assert(lvalue); \
+ assert(rvalue); \
+ assert(data); \
+ \
+ r = conv_func(rvalue, i); \
+ if (r < 0) \
+ log_syntax(unit, LOG_ERR, filename, line, r, \
+ "Failed to parse %s value, ignoring: %s", \
+ #type, rvalue); \
+ \
+ return 0; \
+ } \
+ struct __useless_struct_to_allow_trailing_semicolon__
+
+DEFINE_PARSER(int, int, safe_atoi);
+DEFINE_PARSER(long, long, safe_atoli);
+DEFINE_PARSER(uint16, uint16_t, safe_atou16);
+DEFINE_PARSER(uint32, uint32_t, safe_atou32);
+DEFINE_PARSER(uint64, uint64_t, safe_atou64);
+DEFINE_PARSER(unsigned, unsigned, safe_atou);
+DEFINE_PARSER(double, double, safe_atod);
+DEFINE_PARSER(nsec, nsec_t, parse_nsec);
+DEFINE_PARSER(sec, usec_t, parse_sec);
+DEFINE_PARSER(mode, mode_t, parse_mode);
+
+int config_parse_iec_size(const char* unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ size_t *sz = data;
+ uint64_t v;
+ int r;
+
+ assert(filename);
+ assert(lvalue);
+ assert(rvalue);
+ assert(data);
+
+ r = parse_size(rvalue, 1024, &v);
+ if (r < 0 || (uint64_t) (size_t) v != v) {
+ log_syntax(unit, LOG_ERR, filename, line, r, "Failed to parse size value, ignoring: %s", rvalue);
+ return 0;
+ }
+
+ *sz = (size_t) v;
+ return 0;
+}
+
+int config_parse_si_size(const char* unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ size_t *sz = data;
+ uint64_t v;
+ int r;
+
+ assert(filename);
+ assert(lvalue);
+ assert(rvalue);
+ assert(data);
+
+ r = parse_size(rvalue, 1000, &v);
+ if (r < 0 || (uint64_t) (size_t) v != v) {
+ log_syntax(unit, LOG_ERR, filename, line, r, "Failed to parse size value, ignoring: %s", rvalue);
+ return 0;
+ }
+
+ *sz = (size_t) v;
+ return 0;
+}
+
+int config_parse_iec_uint64(const char* unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ uint64_t *bytes = data;
+ int r;
+
+ assert(filename);
+ assert(lvalue);
+ assert(rvalue);
+ assert(data);
+
+ r = parse_size(rvalue, 1024, bytes);
+ if (r < 0)
+ log_syntax(unit, LOG_ERR, filename, line, r, "Failed to parse size value, ignoring: %s", rvalue);
+
+ return 0;
+}
+
+int config_parse_bool(const char* unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ int k;
+ bool *b = data;
+
+ assert(filename);
+ assert(lvalue);
+ assert(rvalue);
+ assert(data);
+
+ k = parse_boolean(rvalue);
+ if (k < 0) {
+ log_syntax(unit, LOG_ERR, filename, line, k, "Failed to parse boolean value, ignoring: %s", rvalue);
+ return 0;
+ }
+
+ *b = !!k;
+ return 0;
+}
+
+int config_parse_tristate(
+ const char* unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ int k, *t = data;
+
+ assert(filename);
+ assert(lvalue);
+ assert(rvalue);
+ assert(data);
+
+ /* A tristate is pretty much a boolean, except that it can
+ * also take the special value -1, indicating "uninitialized",
+ * much like NULL is for a pointer type. */
+
+ k = parse_boolean(rvalue);
+ if (k < 0) {
+ log_syntax(unit, LOG_ERR, filename, line, k, "Failed to parse boolean value, ignoring: %s", rvalue);
+ return 0;
+ }
+
+ *t = !!k;
+ return 0;
+}
+
+int config_parse_string(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ char **s = data, *n;
+
+ assert(filename);
+ assert(lvalue);
+ assert(rvalue);
+ assert(data);
+
+ if (!utf8_is_valid(rvalue)) {
+ log_syntax_invalid_utf8(unit, LOG_ERR, filename, line, rvalue);
+ return 0;
+ }
+
+ if (isempty(rvalue))
+ n = NULL;
+ else {
+ n = strdup(rvalue);
+ if (!n)
+ return log_oom();
+ }
+
+ free(*s);
+ *s = n;
+
+ return 0;
+}
+
+int config_parse_path(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ char **s = data, *n;
+
+ assert(filename);
+ assert(lvalue);
+ assert(rvalue);
+ assert(data);
+
+ if (!utf8_is_valid(rvalue)) {
+ log_syntax_invalid_utf8(unit, LOG_ERR, filename, line, rvalue);
+ return 0;
+ }
+
+ if (!path_is_absolute(rvalue)) {
+ log_syntax(unit, LOG_ERR, filename, line, 0, "Not an absolute path, ignoring: %s", rvalue);
+ return 0;
+ }
+
+ n = strdup(rvalue);
+ if (!n)
+ return log_oom();
+
+ path_kill_slashes(n);
+
+ free(*s);
+ *s = n;
+
+ return 0;
+}
+
+int config_parse_strv(const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ char ***sv = data;
+ int r;
+
+ assert(filename);
+ assert(lvalue);
+ assert(rvalue);
+ assert(data);
+
+ if (isempty(rvalue)) {
+ char **empty;
+
+ /* Empty assignment resets the list. As a special rule
+ * we actually fill in a real empty array here rather
+ * than NULL, since some code wants to know if
+ * something was set at all... */
+ empty = new0(char*, 1);
+ if (!empty)
+ return log_oom();
+
+ strv_free(*sv);
+ *sv = empty;
+
+ return 0;
+ }
+
+ for (;;) {
+ char *word = NULL;
+
+ r = extract_first_word(&rvalue, &word, WHITESPACE, EXTRACT_QUOTES|EXTRACT_RETAIN_ESCAPE);
+ if (r == 0)
+ break;
+ if (r == -ENOMEM)
+ return log_oom();
+ if (r < 0) {
+ log_syntax(unit, LOG_ERR, filename, line, r, "Invalid syntax, ignoring: %s", rvalue);
+ break;
+ }
+
+ if (!utf8_is_valid(word)) {
+ log_syntax_invalid_utf8(unit, LOG_ERR, filename, line, rvalue);
+ free(word);
+ continue;
+ }
+ r = strv_consume(sv, word);
+ if (r < 0)
+ return log_oom();
+ }
+
+ return 0;
+}
+
+int config_parse_log_facility(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+
+ int *o = data, x;
+
+ assert(filename);
+ assert(lvalue);
+ assert(rvalue);
+ assert(data);
+
+ x = log_facility_unshifted_from_string(rvalue);
+ if (x < 0) {
+ log_syntax(unit, LOG_ERR, filename, line, 0, "Failed to parse log facility, ignoring: %s", rvalue);
+ return 0;
+ }
+
+ *o = (x << 3) | LOG_PRI(*o);
+
+ return 0;
+}
+
+int config_parse_log_level(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+
+ int *o = data, x;
+
+ assert(filename);
+ assert(lvalue);
+ assert(rvalue);
+ assert(data);
+
+ x = log_level_from_string(rvalue);
+ if (x < 0) {
+ log_syntax(unit, LOG_ERR, filename, line, 0, "Failed to parse log level, ignoring: %s", rvalue);
+ return 0;
+ }
+
+ *o = (*o & LOG_FACMASK) | x;
+ return 0;
+}
+
+int config_parse_signal(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ int *sig = data, r;
+
+ assert(filename);
+ assert(lvalue);
+ assert(rvalue);
+ assert(sig);
+
+ r = signal_from_string_try_harder(rvalue);
+ if (r <= 0) {
+ log_syntax(unit, LOG_ERR, filename, line, 0, "Failed to parse signal name, ignoring: %s", rvalue);
+ return 0;
+ }
+
+ *sig = r;
+ return 0;
+}
+
+int config_parse_personality(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ unsigned long *personality = data, p;
+
+ assert(filename);
+ assert(lvalue);
+ assert(rvalue);
+ assert(personality);
+
+ p = personality_from_string(rvalue);
+ if (p == PERSONALITY_INVALID) {
+ log_syntax(unit, LOG_ERR, filename, line, 0, "Failed to parse personality, ignoring: %s", rvalue);
+ return 0;
+ }
+
+ *personality = p;
+ return 0;
+}
+
+int config_parse_ifname(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ char **s = data;
+ int r;
+
+ assert(filename);
+ assert(lvalue);
+ assert(rvalue);
+ assert(data);
+
+ if (isempty(rvalue)) {
+ *s = mfree(*s);
+ return 0;
+ }
+
+ if (!ifname_valid(rvalue)) {
+ log_syntax(unit, LOG_ERR, filename, line, 0, "Interface name is not valid or too long, ignoring assignment: %s", rvalue);
+ return 0;
+ }
+
+ r = free_and_strdup(s, rvalue);
+ if (r < 0)
+ return log_oom();
+
+ return 0;
+}