string-util: move version_is_valid() into generic code

While we are at it, replace the sloppy use of filename_is_valid() by the
less sloppy filename_part_is_valid() (as added by the preceeding
commit), since we don#t want to be too restrictive here. (After all,
version strings invalid as standalone filenames might be valid as part
of filenames, and hence we should allow them).

src/basic/string-util.c

@@ -16,6 +16,7 @@
 #include "macro.h"
 #include "memory-util.h"
 #include "memstream-util.h"
+#include "path-util.h"
 #include "string-util.h"
 #include "strv.h"
 #include "terminal-util.h"
@@ -1296,3 +1297,17 @@ char *startswith_strv(const char *string, char **strv) {
 
         return found;
 }
+
+bool version_is_valid(const char *s) {
+        if (isempty(s))
+                return false;
+
+        if (!filename_part_is_valid(s))
+                return false;
+
+        /* This is a superset of the characters used by semver. We additionally allow "," and "_". */
+        if (!in_charset(s, ALPHANUMERICAL ".,_-+"))
+                return false;
+
+        return true;
+}

src/basic/string-util.h

@@ -275,3 +275,5 @@ char *startswith_strv(const char *string, char **strv);
 
 #define STARTSWITH_SET(p, ...)                                  \
         startswith_strv(p, STRV_MAKE(__VA_ARGS__))
+
+bool version_is_valid(const char *s);

src/sysupdate/meson.build

@@ -15,8 +15,6 @@ systemd_sysupdate_sources = files(
         'sysupdate-transfer.h',
         'sysupdate-update-set.c',
         'sysupdate-update-set.h',
-        'sysupdate-util.c',
-        'sysupdate-util.h',
         'sysupdate.c',
         'sysupdate.h',
 )

src/sysupdate/sysupdate-pattern.c

@@ -8,7 +8,6 @@
 #include "stdio-util.h"
 #include "string-util.h"
 #include "sysupdate-pattern.h"
-#include "sysupdate-util.h"
 
 typedef enum PatternElementType {
         PATTERN_LITERAL,

src/sysupdate/sysupdate-transfer.c

@@ -24,7 +24,6 @@
 #include "sysupdate-pattern.h"
 #include "sysupdate-resource.h"
 #include "sysupdate-transfer.h"
-#include "sysupdate-util.h"
 #include "sysupdate.h"
 #include "tmpfile-util.h"
 #include "web-util.h"

src/sysupdate/sysupdate-util.c

@@ -2,16 +2,3 @@
 
 #include "path-util.h"
 #include "sysupdate-util.h"
-
-bool version_is_valid(const char *s) {
-        if (isempty(s))
-                return false;
-
-        if (!filename_is_valid(s))
-                return false;
-
-        if (!in_charset(s, ALPHANUMERICAL ".,_-+"))
-                return false;
-
-        return true;
-}

src/sysupdate/sysupdate-util.h

@@ -1,6 +0,0 @@
-/* SPDX-License-Identifier: LGPL-2.1-or-later */
-#pragma once
-
-#include <stdbool.h>
-
-bool version_is_valid(const char *s);

src/test/test-string-util.c

@@ -1264,4 +1264,14 @@ TEST(strstrafter) {
         assert_se(!strstrafter(buffer, "-"));
 }
 
+TEST(version_is_valid) {
+        assert_se(!version_is_valid(NULL));
+        assert_se(!version_is_valid(""));
+        assert_se(version_is_valid("0"));
+        assert_se(version_is_valid("5"));
+        assert_se(version_is_valid("999999"));
+        assert_se(version_is_valid("999999.5"));
+        assert_se(version_is_valid("6.2.12-300.fc38.x86_64"));
+}
+
 DEFINE_TEST_MAIN(LOG_DEBUG);