tmpfiles: fix f/F to apply ownership when writing content

When f or F types write content to a file, the mode and ownership
specified in the config should be applied. Previously, ownership was
only applied when create() was used (i.e., when no argument was
specified).

Now we explicitly apply mode and ownership after writing content to
the file.

src/tmpfiles.c

@@ -601,10 +601,6 @@ static void tmpfiles(char *line)
 			mkparent(path, 0755);
 			if (type[1] == '+' || type[0] == 'F') {
 				/* f+/F will create or truncate the file */
-				if (!arg) {
-					rc = create(path, mode ?: 0644, user, group);
-					break;
-				}
 				fp = fopen(path, "w+");
 			} else {
 				/* f will create the file if it doesn't exist */
@@ -613,8 +609,20 @@ static void tmpfiles(char *line)
 			}
 
 			if (fp) {
+				int uid, gid;
+
 				write_arg(fp, arg);
 				rc = fclose(fp);
+
+				/* Apply mode and ownership */
+				if (mode)
+					chmod(path, mode);
+				uid = parse_uid(user);
+				gid = parse_gid(group);
+				if (gid < 0)
+					gid = 0;
+				if (uid >= 0 && chown(path, uid, gid))
+					warn("Failed chown(%s, %d, %d)", path, uid, gid);
 			}
 			break;
 		case 'l': /* Finit extension, like 'L' but only if target exists */