utf8: export utf8 validation functions as part of sd-bus

To write useful bus code clients need to validate utf8 frequently since
the bus reacts allergic to it. Since glibc does not provide any calls
for this, let's provide it as part of libsystemd-bus.

Makefile.am

@@ -1964,6 +1964,7 @@ libsystemd_bus_la_SOURCES = \
 	src/systemd/sd-bus-protocol.h \
 	src/systemd/sd-bus-vtable.h \
 	src/systemd/sd-memfd.h \
+	src/systemd/sd-utf8.h \
 	src/libsystemd-bus/sd-bus.c \
 	src/libsystemd-bus/bus-control.c \
 	src/libsystemd-bus/bus-control.h \
@@ -1995,7 +1996,8 @@ libsystemd_bus_la_SOURCES = \
 	src/libsystemd-bus/kdbus.h \
 	src/libsystemd-bus/sd-memfd.c \
 	src/libsystemd-bus/bus-util.c \
-	src/libsystemd-bus/bus-util.h
+	src/libsystemd-bus/bus-util.h \
+	src/libsystemd-bus/sd-utf8.c
 
 libsystemd_bus_la_LIBADD =  \
 	libsystemd-id128-internal.la \

src/libsystemd-bus/sd-utf8.c

@@ -0,0 +1,36 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2013 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 "util.h"
+#include "utf8.h"
+#include "sd-utf8.h"
+
+const char *sd_utf8_is_valid(const char *s) {
+        assert_return(s, NULL);
+
+        return utf8_is_valid(s);
+}
+
+const char *sd_ascii_is_valid(const char *s) {
+        assert_return(s, NULL);
+
+        return ascii_is_valid(s);
+}

src/shared/utf8.c

@@ -161,7 +161,9 @@ const char *utf8_is_valid(const char *str) {
         assert(str);
 
         for (p = (const uint8_t*) str; *p; ) {
-                int len = utf8_encoded_valid_unichar((const char *)p);
+                int len;
+
+                len = utf8_encoded_valid_unichar((const char *)p);
 
                 if (len < 0)
                         return NULL;

src/systemd/sd-utf8.h

@@ -0,0 +1,28 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+#ifndef fooutf8hfoo
+#define fooutf8hfoo
+
+/***
+  This file is part of systemd.
+
+  Copyright 2013 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/>.
+***/
+
+const char *sd_utf8_is_valid(const char *s);
+const char *sd_ascii_is_valid(const char *s);
+
+#endif